Intraoperative Epiphyseal Perfusion Monitoring Does Not Reliably Predict Osteonecrosis Following Treatment of Unstable SCFE

BACKGROUND

Avascular necrosis (AVN) remains the most dreaded complication of unstable slipped capital femoral epiphysis (SCFE) treatment. Newer closed reduction techniques (with perfusion monitoring) have emerged as a technically straightforward means to address residual SCFE deformity while still minimizing the risk of osteonecrosis. However, limited data exists regarding the reliability of intraoperative epiphyseal perfusion monitoring to predict the development of AVN. The purpose of this study was to evaluate its reliability.

METHODS

We retrospectively reviewed all patients with unstable SCFE who underwent closed or open reduction with epiphyseal perfusion monitoring using an intracranial pressure (ICP) probe from 2015 to 2023 at a single institution with a minimum 6-month radiographic follow-up. Demographic, clinical, and radiographic data were recorded, including duration of symptoms, type of reduction, capsulotomy performed, presence of a waveform on ICP monitoring after epiphyseal fixation, and development of AVN on follow-up radiographs.

RESULTS

Our cohort included 33 hips (32 patients), of which 60.6% (n=20) were male. The average age was 12.5±1.8 years, with a median follow-up of 15.8 months. Eleven hips were treated with open reduction using the modified Dunn technique (10 hips) or anterior approach (1 hip), and 22 hips were treated with inadvertent (5 hips) or purposeful closed reduction using the Leadbetter technique (17 hips). Overall, 8 of the 33 hips in our series (24.2%) developed AVN, 6 of which (20%) had a pulsatile waveform on intraoperative epiphyseal perfusion monitoring. The overall rate of AVN after closed reductions was 31.8% (7 of 22 hips); the incidence of AVN after closed reduction with a detectable waveform was 30% (6 of 20 hips). There was no significant association between time to surgery ( P =0.416) or type of reduction ( P =0.218) and the incidence of AVN.

CONCLUSIONS

In this series, intraoperative epiphyseal perfusion monitoring did not reliably predict the development of osteonecrosis. To our knowledge, this is the first study to report AVN after demonstrable intraoperative epiphyseal perfusion following closed reduction of unstable slips.

LEVEL OF EVIDENCE

Level IV: case series-therapeutic study.

Predictors of Persistent Limp Following Proximal Femoral Varus Osteotomy for Perthes Disease

INTRODUCTION

One of the most popular containment procedures for Legg-Calvé-Perthes disease (LCPD) is proximal femur varus osteotomy (PFO). While generally successful in achieving containment, PFO can cause limb length discrepancy, abductor weakness, and (of most concern for families) a persistent limp. While many studies have focused on radiographic outcomes following containment surgery, none have analyzed predictors of this persistent limp. The aim of this study was to determine clinical, radiographic, and surgical risk factors for persistent limp 2 years after PFO in children with LCPD.

METHODS

A retrospective review of a prospectively collected multicenter database was conducted for patients aged 6 to 11 years at disease onset with unilateral early-stage LCPD (Waldenström I) who underwent PFO. Limp status (no, mild, and severe), age, BMI, and pain scores were obtained at initial presentation, 3-month, and 2-year postoperative visits. Preoperative and follow-up radiographs were used to measure traditional morphologic hip metrics including acetabular index (AI), lateral center-edge angle (LCEA), and femoral neck-shaft angle (NSA). Univariate analysis as well as multivariate logistic regression models were used to analyze factors associated with mild and severe limp at the 2-year visit.

RESULTS

A total of 95 patients met the inclusion criteria, and of these 50 patients underwent concomitant greater trochanter apophysiodesis (GTA) at the time of PFO. At the 2-year visit, there were 38 patients (40%) with a mild or severe limp. Multivariate logistic regression revealed no significant radiographic factors associated with a persistent limp. However, lower 2-year BMI and undergoing GTA were associated with decreased rates of persistent limp regardless of age (P<0.05). When stratifying by age of disease onset, apophysiodesis appeared to be protective against any severity of limp in patients aged 6 to 8 years old (P= 0.03), but not in patients 8 years or older (P= 0.49).

CONCLUSIONS

Persistent limp following PFO is a frustrating problem that was seen in 40% of patients at 2 years. However, lower follow-up BMI and performing a greater trochanter apophysiodesis, particularly in patients younger than 8 years of age, correlated with a lower risk of postoperative limp.

Risk Factors for Suboptimal Outcome of FAI Surgery in the Adolescent Patient

BACKGROUND

Surgical treatment for adolescent patients with femoroacetabular impingement (FAI) is increasing. The purpose of this study was to determine the clinical outcomes of FAI surgery in a multicenter cohort of adolescent patients and to identify predictors of suboptimal outcomes.

METHODS

One hundred twenty-six adolescent hips (114 patients < 18 years of age) undergoing surgery for symptomatic FAI were studied from a larger multicenter cohort. The group included 74 (58.7%) female and 52 male hips (41.3%) with a mean age of 16.1 (range 11.3 to 17.8). Clinical outcomes included the modified Harris Hip Score (mHHS), Hip disability and Osteoarthritis Outcome Score (5 domains), and University of California Los Angeles activity score. Failure was defined as revision surgery or clinical failure (inability to reach minimally clinical important differences or patient acceptable symptoms state for the mHHS). Statistical analysis was used to identify factors significantly associated with failure.

RESULTS

There was clinically important improvement in all patient-reported outcomes for the overall group, but an 18.3% failure rate. This included a revision rate of 8.7%. Females were significantly more likely than males to be classified as a failure (25.7 vs. 7.7%, P =0.01), in part because of lower preoperative mHHS (59.1 vs. 67.0, P < 0.001). Mild cam deformity (alpha angle <55 degrees) was present in 42.5% of female hips compared with 17.3% male hips. Higher alpha angles were inversely correlated with failure. Alpha angles >63 have a failure rate of 8.3%, between 55 and 63 degrees, 12.0% failure rate, and <55 degrees (mild cam) failure rate of 37.5%. Patients who participated in athletics had a 10.3% failure rate compared with nonathletes at 25.0% ( P =0.03, RR (relative risk) 2.4).

CONCLUSIONS

Adolescent patients undergoing surgical treatment for FAI generally demonstrate significant improvement. However, female sex, mild cam deformities, and lack of sports participation are independently associated with higher failure rates. These factors should be considered in surgical decision-making and during patient counseling.

LEVEL OF EVIDENCE

Level III-retrospective comparative study.

Femoral Head Remodeling After Surgical Reduction of Developmental Hip Dislocations

OBJECTIVE

Developmental dysplasia of the hip is prevalent and is associated with dysplasia of both the femoral head and acetabulum. There is a paucity of literature describing femoral head remodeling after surgical reduction of developmentally dislocated hips. The purpose of this study was to describe and quantify changes in femoral head sphericity after closed or open reduction for developmental dysplasia of the hip.

METHODS

A retrospective cohort study was performed including patients with typical developmental hip dislocations who underwent closed or open reduction from 2009 to 2022 at a single institution and had immediate postoperative and average 3-week follow-up magnetic resonance imaging (MRI) scans. A subset of patients also had 3-year follow-up MRI scans. Patients with insufficient imaging or bony procedures at the time of reduction were excluded. We developed a technique to quantify femoral head "sphericity" by comparing differences in measured radii of the femoral head on axial and coronal plane MRI slices. We then calculated the variance of the radii for each plane and averaged these to calculate a combined variance. The variance was used to represent "sphericity," with a larger variance indicating a wider distribution of radii and thus a less spherical shape.

RESULTS

A total of 74 patients (69 females) with 96 hips were included in this series. The median age of the child at the time of reduction was 8.7 months [interquartile range (IQR): 2.2]. Over half (58.3%) of the hips had a closed reduction, whereas the remaining were open reduced (41.7%). Immediately postoperatively, at the 3-week time point, and at the 3-year time point the median combined variance was 1.1 (IQR: 3.93), 0.51 (IQR: 1.32), and 0.31 (IQR: 0.50), respectively, indicating improved sphericity over time.

CONCLUSIONS

Sphericity of the femoral head in developmental hip dislocations improves in both the immediate postoperative period, as well as the first few years after reduction. Further research is needed to evaluate the mechanism of remodeling, the ideal timing of reduction, and the relationship between femoral head and acetabular remodeling.

LEVEL OF EVIDENCE

Level IV-case series, therapeutic study.

What Are the Psychosocial Effects of Pavlik Harness Treatment? A Prospective Study on Perceived Impact on Families and Maternal-Infant Bonding

BACKGROUND

The Pavlik harness (PH) is the most common treatment for infants with developmental dysplasia of the hip. Although success rates are high when used appropriately, brace treatment may impact family function and parental bonding. The purpose of this study was to prospectively determine how PH treatment affected these psychosocial variables.

METHODS

This is a prospective, single-surgeon study at a tertiary-care, urban, academic children's hospital between November 2022 and March 2023. All patients newly treated with a Pavlik were eligible. Caregivers were administered the Postpartum Bonding Questionnaire and the Revised Impact on Family Scale (rIOFS) at the baseline visit and 2- and 6 weeks following treatment initiation. Demographic and treatment-specific information was collected through surveys and retrospective chart review. Descriptive statistics and bivariate analysis were used.

RESULTS

A total of 55 caregiver-child dyads were included in the final analysis. Most patients were female (89%) and/or first-born (73%). Forty (73%) hips were diagnosed as having stable dysplasia. rIOFS scores steadily improved from baseline, through 2- and 6 weeks posttreatment initiation. Six-week rIOFS scores were significantly lower than both baseline ( P= 0.002) and 2 weeks ( P =0.018). Average parental bonding scores also improved steadily throughout treatment and did not surpass the threshold of clinical concern at any time. Neither full-time harness use (24 h/d vs. 23 h/d based upon clinical stability) nor age at treatment initiation had a statistically significant effect on parental bonding or family functioning (all P >0.05). Additional demographic variables such as birth order, parental history of anxiety/depression, and relative socioeconomic disadvantage also had no significant effect on psychosocial outcomes.

CONCLUSION

PH treatment did not significantly impact maternal-fetal bonding or family dynamics. Relative to other pediatric diseases, PH treatment has an impact on family life greater than that of single-leg spica, but less than that of school-age children with chronic medical illnesses. As PH treatment is a widely used treatment for infantile developmental dysplasia of the hip, this study provides information that clinicians may use to more accurately counsel families and assuage parental concerns.

LEVELS OF EVIDENCE

Level IV-prospective uncontrolled cohort study.

Opioid Analgesia Compared with Non-Opioid Analgesia After Operative Treatment for Pediatric Supracondylar Humeral Fractures: Results from a Prospective Multicenter Trial

BACKGROUND

Minimal pain and opioid use after operative treatment for pediatric supracondylar humeral fractures have been previously described; however, opioid-prescribing practices in the United States remain variable. We hypothesized that children without an opioid prescription would report similar postoperative pain compared with children prescribed opioids following closed reduction and percutaneous pinning (CRPP) of supracondylar humeral fractures.

METHODS

Children who were 3 to 12 years of age and were undergoing CRPP for a closed supracondylar humeral fracture were prospectively enrolled in a multicenter, comparative study. Following a standardized dosing protocol, oxycodone, ibuprofen, and acetaminophen were prescribed at 2 hospitals (opioid cohort), and 2 other hospitals prescribed ibuprofen and acetaminophen alone (non-opioid cohort). The children's medication use and the daily pain that they experienced (scored on the Wong-Baker FACES Scale) were recorded at postoperative days 1 to 7, 10, 14, and 21, using validated text-message protocols. Based on an a priori power analysis, at least 64 evaluable subjects were recruited per cohort.

RESULTS

A total of 157 patients were evaluated (81 [52%] in the opioid cohort and 76 [48%] in the non-opioid cohort). The median age at the time of the surgical procedure was 6.2 years, and 50% of the subjects were male. The mean postoperative pain scores were low overall (<4 of 10), and there were no significant differences in pain ratings between cohorts at any time point. No patient demographic or injury characteristics were correlated with increased pain or medication use. Notably, of the 81 patients in the opioid cohort, 28 (35%) took no oxycodone and 40 (49%) took 1 to 3 total doses across the postoperative period. Patients rarely took opioids after postoperative day 2. A single patient in the non-opioid cohort (1 [1%] of 76) received a rescue prescription of opioids after presenting to the emergency department with postoperative cast discomfort.

CONCLUSIONS

Non-opioid analgesia following CRPP for pediatric supracondylar humeral fractures was equally effective as opioid analgesia. When oxycodone was prescribed, 84% of children took 0 to 3 total doses, and opioid use fell precipitously after postoperative day 2. To improve opioid stewardship, providers and institutions can consider discontinuing the routine prescription of opioids following this procedure.

LEVEL OF EVIDENCE

Therapeutic Level II . See Instructions for Authors for a complete description of levels of evidence.

Rib-to-spine and rib-to-pelvis magnetically controlled growing rods: does the law of diminishing returns still apply?

PURPOSE

The Law Of Diminishing Returns (LODR) has been demonstrated for traditional growing rods, but there is conflicting data regarding the lengthening behavior of Magnetically Controlled Growing Rods (MCGR). This study examines a cohort of patients with early-onset scoliosis (EOS) with rib-to-spine or rib-to-pelvis-based MCGR implants to determine if they demonstrate the LODR, and if there are differences in lengthening behaviors between the groups.

METHODS

A prospectively collected multicenter EOS registry was queried for patients with MCGR with a minimum 2-year follow-up. Patients with rib-based proximal anchors and either spine- or pelvis-based distal anchors were included. Patients with non-MCGR, unilateral constructs, < 3 lengthenings, or missing > 25% datapoints were excluded. Patients were further divided into Primary-MCGR (pMCGR) and Secondary-MCGR (sMCGR).

RESULTS

43 rib-to-spine and 31 rib-to-pelvis MCGR patients were included. There was no difference in pre-implantation, post-implantation and pre-definitive procedure T1-T12 height, T1-S1 height, and major Cobb angles between the groups (p > 0.05). Sub-analysis was performed on 41 pMCGR and 19 sMCGR rib-to-spine patients, and 31 pMCGR and 17 sMCGR rib-to-pelvis patients. There is a decrease in rod lengthenings achieved at subsequent lengthenings for each group: rib-to-spine pMCGR (rho = 0.979, p < 0.001), rib-to-spine sMCGR (rho = 0.855, p = 0.002), rib-to-pelvis pMCGR (rho = 0.568, p = 0.027), and rib-to-pelvis sMCGR (rho = 0.817, p = 0.007). Rib-to-spine pMCGR had diminished lengthening over time for idiopathic, neuromuscular, and syndromic patients (p < 0.05), with no differences between the groups (p > 0.05). Rib-to-pelvis pMCGR neuromuscular patients had decreased lengthening over time (p = 0.01), but syndromic patients had preserved lengthening over time (p = 0.65).

CONCLUSION

Rib-to-spine and rib-to-pelvis pMCGR and sMCGR demonstrate diminished ability to lengthen over subsequent lengthenings.

A novel quantitative approach to evaluate femoral head perfusion by contrast-enhanced ultrasound: A pilot study in infants with developmental dysplasia of the hip

Avascular necrosis (AVN) is a major morbidity that can occur after surgical reduction of a hip with developmental dysplasia. Early detection of changes in femoral head perfusion during surgery may help detect a hip at risk for AVN and guide intraoperative management. Contrast-enhanced ultrasound (CEUS) can be employed for visualization of femoral head perfusion. In this study we evaluate a quantitative CEUS technique to assess femoral head perfusion pre- and post-surgical reduction. CEUS images were obtained following a bolus injection of an ultrasound contrast agent, prior to and again following surgical reduction and casting. An image processing technique called delta projection was used to quantify hip perfusion, measuring peak enhancement (PE) and perfusion index (PI). We analyzed CEUS images of the hips of eight patients, including seven females, whose ages ranged from 4 months to 1 year. In five hips, perfusion increased following surgery, with a mean pre-surgery PE of 6.7 ±2.5(± SE) and PI of 10.5 ±6.3; and a post-reduction PE of 13.1±6.1 (p=0.07) and PI of 14.2 ±6.2 (p=0.008). The change in contrast visualization was observed to be greater within the central aspect of the cartilaginous femoral epiphysis. The proposed technique can quantify pre- and post-surgical perfusion changes on CEUS images in patients with developmental dysplasia. This quantitative technique may provide a more objective and accurate assessment of changes in femoral head perfusion that may have the potential to be indicative of the risk of developing AVN.

The Impact of Age on Clinical Outcomes of Acetabular Microfracture During FAI Surgery

BACKGROUND

Full-thickness acetabular cartilage lesions are common findings during primary surgical treatment of femoroacetabular impingement (FAI).

PURPOSE

To evaluate clinical outcomes after acetabular microfracture performed during FAI surgery in a prospective, multicenter cohort.

STUDY DESIGN

Cohort Study; Level of evidence, 3.

METHODS

Patients with FAI who had failed nonoperative management were prospectively enrolled in a multicenter cohort. Preoperative and postoperative (mean follow-up, 4.3 years) patient-reported outcome measures were obtained with a follow-up rate of 81.6% (621/761 hips), including 54 patients who underwent acetabular microfracture. Patient characteristics, radiographic parameters, intraoperative disease severity, and operative procedures were analyzed. Propensity matching using linear regression was used to match 54 hips with microfracture to 162 control hips (1:3) to control for confounding variables. Subanalyses of hips ≤35 and >35 years of age with propensity matching were also performed.

RESULTS

Patients who underwent acetabular microfracture were more likely to be male (81.8% vs 40.9%; P < .001), be older in age (35.0 vs 29.9 years; P = .001), have a higher body mass index (27.2 vs 25.0; P = .001), and have a greater alpha angle (69.6° vs 62.3°; P < .001) compared with the nonmicrofracture cohort (n = 533). After propensity matching to control for covariates, patients treated with microfracture displayed no differences in the modified Harris Hip Score or Hip Disability and Osteoarthritis Outcome Score (P = .22-.95) but were more likely to undergo total hip arthroplasty (THA) (13% [7/54] compared with 4% [6/162] in the control group; P = .002), and age >35 years was associated with conversion to THA after microfracture. Microfracture performed at or before 35 years of age portended good outcomes with no significant risk of conversion to THA at the most recent follow-up.

CONCLUSION

Microfracture of acetabular cartilage defects appears to be safe and associated with reliably improved short- to mid-term results in younger patients; modified expectations should be realized when full-thickness chondral lesions are identified in patients >35 years of age.

Socioeconomic Deprivation and its Associations With Follow-up Compliance After In Situ Pinning of Slipped Capital Femoral Epiphysis

BACKGROUND

Slipped capital femoral epiphysis (SCFE) is a common cause of hip pain in adolescents and is most often treated by in situ screw fixation. Orthopaedic follow-up is critical after treatment for SCFE due to risks of complications and subsequent contralateral slip. Recent studies have shown that socioeconomic deprivation is associated with decreased fracture care compliance, but no studies have explored this relationship with SCFEs. The study aims to determine the relationship between socioeconomic deprivation and SCFE follow-up care compliance.

METHODS

This study included pediatric patients treated with in situ pinning of SCFE between 2011 and 2019 at a single tertiary-care urban children's hospital. Demographic and clinical information were obtained from electronic medical records. The Area Deprivation Index (ADI) was used to quantify the socioeconomic deprivation of each. Outcome variables included patient age and status of physeal closure at the most recent appointment, in addition to the length of follow-up (mo). Statistical relationships were evaluated using nonparametric bivariate analysis and correlation.

RESULTS

We identified 247 evaluable patients; 57.1% were male, and the median age was 12.4 years. Most slips were stable (95.1%) and treated with isolated unilateral pinning (55.9%). Median length of follow-up was 11.9 months (interquartile range, 4.95 to 23.1) with median patient age at final visit of 13.6 years (interquartile range, 12.4 to 15.1). Only 37.2% of patients were followed until physeal closure. The mean ADI spread in this sample was similar to the national distribution. However, patients in the most deprived quartile were lost to follow-up significantly earlier (median, 6.5 mo) than those in the least deprived quartile (median, 12.5 mo; P <0.001). Throughout the entire cohort, there was a significant, inverse relationship between deprivation and follow-up length ( rs (238) = -0.3; P <0.001), with this relationship most pronounced in the most deprived quartile.

CONCLUSIONS

In this sample, ADI spread was representative of national trends, and the incidence of SCFE was distributed evenly across deprivation quartiles. However, follow-up length does not mirror this relationship; increased socioeconomic deprivation is associated with an earlier loss to follow-up (often well before physeal closure).

LEVEL OF EVIDENCE

Level II-retrospective prognostic study.

A Prospective, Multicenter Study of Developmental Dysplasia of the Hip: What Can Patients Expect After Open Reduction?

BACKGROUND

Although there are several predominantly single-center case series in the literature, relatively little prospectively collected data exist regarding the outcomes of open hip reduction (OR) for infantile developmental dysplasia of the hip (DDH). The purpose of this prospective, multi-center study was to determine the outcomes after OR in a diverse patient population.

METHODS

The prospectively collected database of an international multicenter study group was queried for all patients treated with OR for DDH. Minimum follow-up was 1 year. Proximal femoral growth disturbance (PFGD) was defined by consensus review using Salter's criteria. Persistent acetabular dysplasia was defined as an acetabular index >90th percentile for age. Statistical analyses were performed to compare preoperative and operative characteristics that predicted re-dislocation, PFGD, and residual acetabular dysplasia.

RESULTS

A cohort of 232 hips (195 patients) was identified; median age at OR was 19 months (interquartile range 13 to 28) and median follow-up length was 21 months (interquartile range 16 to 32). Re-dislocation occurred in 7% of hips (n=16/228). The majority (81%; n=13/16) occurred in the first year after initial OR. Excluding patients with repeat dislocation, 94.5% of hips were IHDI 1 at most recent follow-up. On the basis of strict radiographic review, some degree of PFGD was present in 44% of hips (n=101/230) at most recent follow-up. Seventy-eight hips (55%) demonstrated residual dysplasia compared with established normative data. Hips that had a pelvic osteotomy at index surgery had about half the rate of residual dysplasia (39%; n=32/82) versus those without a pelvic osteotomy with at least 2 years follow-up (78%; n=46/59).

CONCLUSIONS

In the largest prospective, multicenter study to date, OR for infantile DDH was associated with a 7% risk of re-dislocation, 44% risk of PFGD, and 55% risk of residual acetabular dysplasia at short term follow-up. The incidence of these adverse outcomes is higher than previous reports. Patients treated with concomitant pelvic osteotomy had lower rates of residual dysplasia. These prospectively collected, multicenter data provide better generalizable information to improve family education and appropriately set expectations.

LEVEL OF EVIDENCE

Level II, prospective comparative study.

Developmental Dysplasia of the Hip From Birth to Adolescence: Clear Indications and New Controversies

It is important to be knowledgeable about the latest information on the diagnosis and the evidence-based management of developmental hip dysplasia and dislocation from birth through adolescence. The focus should be on the effect of the problem; normal growth and development of the hip joint; and the pathoanatomy, natural history, and long-term outcomes of developmental dysplasia of the hip, hip subluxation, and dysplasia. Many controversies exist in the management of this complex spectrum of disorders.

Implicit Racial Bias in Pediatric Orthopaedic Surgery

INTRODUCTION

Racial and ethnic minority patients continue to experience disparities in health care. It is important to understand provider-level factors that may contribute to these inequities. This study aims to evaluate the presence of implicit racial bias among pediatric orthopaedic surgeons and determine the relationship between bias and clinical decision making.

METHODS

A web-based survey was distributed to 415 pediatric orthopaedic surgeons. One section measured for potential implicit racial bias using a child-race implicit association test (IAT). IAT scores were compared with US physicians and the US general population using publicly available data. Another section consisted of clinical vignettes with associated questions. For each vignette, surgeons were randomly assigned a single race-version, White or Black. Vignette questions were grouped into an opioid recommendation, management decision, or patient perception category for analysis based on subject tested. Vignette answers from surgeons with IAT scores that were concordant with their randomized vignette race-version (ie, surgeon with pro-White score assigned White vignette version) were compared with those that were discordant.

RESULTS

IAT results were obtained from 119 surveyed surgeons (29% response rate). Overall, respondents showed a minor pro-White implicit bias ( P <0.001). Implicit bias of any strength toward either race was present among 103/119 (87%) surgeons. The proportion of pediatric orthopaedic surgeons with a strong pro-White implicit bias (29%) was greater than that of US physicians overall (21%, P =0.032) and the US general population (19%, P =0.004). No differences were found in overall opioid recommendations, management decisions, or patient perceptions between concordant and discordant groups.

CONCLUSION

Most of the pediatric orthopaedic surgeons surveyed demonstrated implicit racial bias on IAT testing, with a large proportion demonstrating strong pro-White bias. Despite an association between implicit bias and clinical decision making in the literature, this study observed no evidence that implicit racial bias affected the management of pediatric fractures.

LEVEL OF EVIDENCE

Level IV.

MRI Predictors of Residual Dysplasia in Developmental Dysplasia of the Hip Following Open and Closed Reduction

BACKGROUND

Following open or closed reduction for children with developmental dysplasia of the hip, there remains a significant risk of residual acetabular dysplasia which can compromise the long-term health of the hip joint. The purpose of this study was to use postoperative in-spica magnetic resonance imaging (MRI) data to determine factors predictive of residual acetabular dysplasia at short-term follow-up.

METHODS

We retrospectively reviewed 63 hips in 48 patients which underwent closed or open reduction and spica casting for developmental dysplasia of the hip. MRI performed in-spica at ∼3-week follow-up were used to assess 11 validated metrics and 2 subjective factors. Acetabular index (AI) was measured on anteroposterior pelvic radiographs at 2-year postoperative follow-up. Binary logistic regression was then used to identify variables predictive of residual dysplasia, defined as an AI greater than the 90th percentile for age based on historic normative data.

RESULTS

Average age at surgical reduction was 9.3±3.2 months. 58.7% (37/63) of reductions were open. A total of 43 (68.3%) hips demonstrated residual acetabular dysplasia at 2 years postoperatively based on normative values. In those with persistent dysplasia, patients were on average older at the time of reduction (10.0 mo±3.2 vs. 8.0 mo±2.8, P=0.010) and more likely female (88.4% vs. 60.0%, P=0.010). Patients with residual dysplasia were more likely to have mild subluxation on postoperative MRI (40.0% vs. 10.5%, P=0.022). Hips with a cartilaginous acetabular index (CAI) of >23 degrees were 7.6 times more likely to develop residual dysplasia. Type of reduction (ie, closed vs. open) did not appear to influence the rate of residual dysplasia (P=0.682).

CONCLUSION

In this series, the rate of residual dysplasia after surgical reduction was higher than most previous reports, with no appreciable difference between closed and open reductions. Older age, female sex, and a higher CAI were associated with a greater risk of persistent radiographic dysplasia. In particular, hips with a CAI >23 degrees were 7.6 times more likely to be dysplastic at 2-year follow-up.

LEVEL OF EVIDENCE

Level III.

Does intraoperative CT navigation increase the accuracy of pedicle screw placement in pediatric spinal deformity surgery? A systematic review and meta-analysis

PURPOSE

Although pediatric spinal deformity correction using pedicle screws has a very low rate of complications, the long-term consequences of screw malposition is unknown. CT navigation has been proposed to improve screw accuracy. The aim of this study was to determine whether intraoperative navigation during pedicle screw placement in pediatric scoliosis makes screw placement more accurate. We also examined radiation exposure, operative time blood loss and complications with and without the use of CT navigation in pediatric spinal deformity surgery.

METHODS

A systematic review of the literature was conducted. After screening, 13 articles were qualitatively and quantitatively analyzed to be used for the review. A random effects meta-analysis using REML methodology was employed to compare outcomes of screw accuracy, estimated blood loss, radiation exposure, and surgical duration.

RESULTS

Screws placed with CT navigation surgery were three times as likely to be deemed "acceptable" compared with screws placed with freehand and 2D fluoroscopy assistance, twice as likely to be "perfect", and only 1/3 as likely to be potentially unsafe (all p value < 0.01). EBL was not significantly different between groups; however, operative time was roughly thirty minutes longer on average. Random effects analysis showed no significant difference in effective dose radiation while using CT navigation (p = 0.06).

CONCLUSION

This systematic review of the literature demonstrates that intraoperative navigation results in more accurate pedicle screw placement compared to non-navigated techniques. We found that blood loss was similar in navigated and non-navigated surgery. Operative time was found to be approximately a half hour longer on average in navigated compared to non-navigated surgery. Effective radiation dose trended higher in navigated cases compared to non-navigated cases but did not reach statistical significance.

Interobserver and Intraobserver Reliability in the Salter Classification of Avascular Necrosis of the Femoral Head in Developmental Dysplasia of the Hip

BACKGROUND

Avascular necrosis (AVN) of the femoral head is a concerning complication that can result from treatments for developmental dysplasia of the hip (DDH). AVN can lead to degenerative osteoarthritis, persistent acetabular dysplasia, reduced function, and continuing hip pain. The incidence of AVN reported in the DDH literature is widely varied (0% to 73%). This variability may arise from lack of consensus on what constitutes true AVN in this patient population, and lack of clear criteria provided in studies reporting incidence rates.

METHODS

A multicentre, prospective database of infants diagnosed with DDH between 2010 and 2014 from 0 to 18 months of age was analyzed for patients treated by closed reduction (CR). Twelve pediatric orthopaedic surgeons completed 2 rounds of AVN assessments. Deidentified anteroposterior radiographs at most recent follow-up were provided to surgeons along with patient age at radiographic assessment, length of follow-up, ands affected hip. Ten of 12 surgeons completed a third round of assessments where they were provided with 1 to 2 additional radiographs within the follow-up period. Radiographic criteria for total AVN described by Salter and colleagues were used. Surgeons rated the presence of AVN as "yes" or "no" and kappa values were calculated within and between rounds.

RESULTS

A total of 69 hips in 60 patients were assessed for AVN a median of 22 months (range: 12 to 36) post-CR. Interobserver kappa values for rounds 1, 2, and 3 were 0.52 (range: 0.11 to 0.90), 0.61 (range: 0.21 to 0.90), and 0.53 (range: 0.10 to 0.79), respectively. Intraobserver agreement for AVN diagnosis was an average of 0.72 (range: 0.31 to 0.96).

CONCLUSIONS

Despite using the most commonly referenced diagnostic criteria, radiographic diagnosis of AVN following CR in DDH patients demonstrated only moderate agreement across surgeons. The addition of sequential radiographs did not improve cross-observer reliability, and while substantial agreement was seen within observers, the range of intraobserver kappa values was large.

LEVEL OF EVIDENCE

Level I-diagnostic study.

Residual Acetabular Dysplasia in the Reduced Hip

BACKGROUND

Residual acetabular dysplasia occurs in up to a third of patients treated successfully for developmental dysplasia of the hip (DDH) and has been found to be a significant risk factor for early hip osteoarthritis (OA).

DISCUSSION

Age at the time of initial reduction and the initial severity of DDH have been linked to residual acetabular dysplasia. An anteroposterior pelvic radiograph is the main diagnostic modality, but MRI also provides valuable information, particularly in equivocal cases. The literature supports intervening when significant residual acetabular dysplasia persists at 4-5 years of age, and common surgical indications include acetabular index (AI) > 25°-30°, lateral center-edge angle (LCEA) < 8°-10°, and a broken Shenton's line on radiographs; and a cartilaginous acetabular angle (CAI) > 18°, cartilaginous center-edge angle (CCE) < 13°, and/or the presence of high-signal intensity areas on MRI. Surgical options include redirectional pelvic osteotomies and reshaping acetabuloplasties, which provide comparable radiographic and clinical results.

CONCLUSION

RAD is common after treatment of DDH and requires regular follow-up for diagnosis and appropriate management to decrease the long-term risk of OA. Long-term outcomes of patients treated with pelvic osteotomies are generally favorable, and the risk of OA can be decreased, although the risk of total hip replacement in the long-term remains.

Hip Morphology in Early-stage LCPD: Is There an Argument for Anatomic-specific Containment?

BACKGROUND

Early containment surgery has become increasingly popular in Legg-Calvé-Perthes Disease (LCPD), especially for older children. These procedures treat the proximal femur, the acetabulum, or both, and most surgeons endorse the same surgical option regardless of an individual patient's anatomy. This "one-surgery-fits-all" approach fails to consider potential variations in baseline anatomy that may make one option more sensible than another. We sought to describe hip morphology in a large series of children with newly diagnosed LCPD, hypothesizing that variation in anatomy may support the concept of anatomic-specific containment.

METHODS

A retrospective review of a prospectively collected multicenter database was conducted for patients aged 6 to 11 at diagnosis. To assess anatomy before significant morphologic changes secondary to the disease itself, only patients in Waldenström stages IA/IB were included. Standard hip radiographic measurements including acetabular index, lateral center-edge angle, proximal femoral neck-shaft angle (NSA), articulotrochanteric quartiles, and extrusion index (EI) were made on printed anteroposterior pelvis radiographs. Age-specific percentiles were calculated for these measures using published norms. Significant outliers (≤10th/≥90th percentile) were reported where applicable.

RESULTS

A total of 168 patients with mean age at diagnosis of 8.0±1.3 years met inclusion criteria (81.5% male). Mean acetabular index for the entire cohort was 16.8±4.1 degrees; 58 hips (34.5%) were significantly dysplastic compared with normative data. Mean lateral center-edge angle was 15.9±5.2 degrees at diagnosis; 110 (65.5%) were ≤10th percentile indicating dysplasia (by this metric). Mean NSA overall was 136.5±7.0 degrees. Fifty-one (30.4%) and 20 (11.9%) hips were significantly varus (≤10th percentile) or valgus (≥90th percentile), respectively. Thirty-five hips (20.8%) were the third articulo-trochanteric quartiles or higher suggesting a higher-riding trochanter at baseline. Mean EI was 15.5%±9.0%, while 63 patients (37.5%) had an EI ≥20%.

CONCLUSIONS

The present study finds significant variation in baseline anatomy in children with early-stage LCPD, including a high prevalence of coexisting acetabular dysplasia as well as high/low NSAs. These variations suggest that the "one-surgery-fits-all" approach may lack specificity for a particular patient; a potentially wiser option may be an anatomic-specific containment operation (eg, acetabular-sided osteotomy for coexisting dysplasia, varus femoral osteotomy for valgus NSA).

LEVEL OF EVIDENCE

Level IV.

Is There a Benefit to Weaning Pavlik Harness Treatment in Infantile DDH?

BACKGROUND

Following successful treatment of developmental hip dysplasia with a Pavlik harness, controversy exists over the benefit of continued harness use for an additional "weaning" period beyond ultrasonographic normalization versus simply terminating treatment. Although practitioners are often dogmatic in their beliefs, there is little literature to support the superiority of 1 protocol over the other. The purpose of this study was to compare the radiographic outcomes of 2 cohorts of infants with developmental hip dysplasia treated with Pavlik harness, 1 with a weaning protocol and 1 without.

METHODS

This was a comparative review of patients with dislocated/reducible hips and stable dysplasia from 2 centers. All patients had pretreatment ultrasounds, and all started harness treatment before 3 months of age. On the basis of power analysis, a sufficient cohort of hips were matched based on clinical examination, age at initiation, initial α angle, and initial percent femoral head coverage. Patients from institution W (weaned) were weaned following ultrasonographic normalization, whereas those from institution NW (not weaned) immediately ceased treatment. The primary outcome was the acetabular index at 1 year of age.

RESULTS

In total, 16 dislocated/reducible and 16 stable dysplastic hips were matched at each center (64 total hips in 53 patients). Initial α angle and initial femoral head coverage were not different between cohorts for either stable dysplasia (P=0.59, 0.81) or dislocated/reducible hips (P=0.67, 0.70), respectively. As expected, weaned hips were treated for significantly longer in both the stable dysplasia (1540.4 vs. 1066.3 h, P<0.01), and dislocated/reducible cohorts (1596.6 vs. 1362.5 h, P=0.01). Despite this, we found no significant difference in the acetabular index at 1 year in either cohort (22.8 vs. 23.1 degrees, P=0.84 for stable dysplasia; 23.9 vs. 24.8 degrees, P=0.32 for Ortolani positive).

CONCLUSIONS

Despite greater total harness time, infants treated with additional Pavlik weaning did not demonstrate significantly different radiographic results at 1 year of age compared with those who were not weaned. However, differences in follow-up protocols between centers support the need for a more rigorous randomized controlled trial.

LEVEL OF EVIDENCE

Level III.

Reliability of the modified lateral pillar classification for Legg Calvé Perthes disease performed by a large group of international paediatric orthopaedic surgeons

PURPOSE

The modified lateral pillar classification (mLPC) is used for prognostication in the fragmentation stage of Legg Calvé Perthes disease. Previous reliability assessments of mLPC range from fair to good agreement when evaluated by a small number of observers with pre-selected radiographs. The purpose of this study was to determine the inter-observer and intra-observer reliability of mLPC performed by a group of international paediatric orthopaedic surgeons. Surgeons self-selected the radiograph for mLPC assessment, as would be done clinically.

METHODS

In total, 40 Perthes cases with serial radiographs were selected. For each case, 26 surgeons independently selected a radiograph and assigned mLPC and 21 raters re-evaluated the same 40 cases to establish intra-observer reliability. Rater performance was determined through surgeon consensus using the mode mLPC as 'gold standard'. Inter-observer and intra-observer reliability data were analysed using weighted kappa statistics.

RESULTS

The weighted kappa for inter-observer correlation for mLPC was 0.64 (95% confidence interval: 0.55 to 0.74) and was 0.82 (range: 0.35 to 0.99) for intra-observer correlation. Individual surgeon's overall performance varied from 48% to 88% agreement. Surgeon mLPC performance was not influenced by years of experience (p = 0.51). Radiograph selection did not influence gold standard assignment of mLPC. There was greater agreement on cases of mild B hips and severe C hips.

CONCLUSIONS

mLPC has low good inter-observer agreement when performed by a large number of surgeons with varied experience. Surgeons frequently chose different radiographs, with no impact on mLPC agreement. Further refinement is needed to help differentiate hips on the border of group B and C.

LEVEL OF EVIDENCE

III.

Socioeconomic Deprivation and Its Adverse Association with Adolescent Fracture Care Compliance

Background:

Socioeconomic deprivation increases fracture incidence in adolescents, but its impact on fracture care is unknown. The area deprivation index (ADI), which incorporates 17 factors from the U.S. Census, measures socioeconomic deprivation in neighborhoods. This investigation aimed to determine the impact of socioeconomic deprivation and other socioeconomic factors on fracture care compliance in adolescents.

Methods:

This study included patients who were 11 to 18 years of age and received fracture care at a single urban children’s hospital system between 2015 and 2017. Demographic information (sex, race, caregiver status, insurance type) and clinical information (mechanism of injury, type of treatment) were obtained. The ADI, which has a mean score of 100 points and a standard deviation of 20 points, was used to quantify socioeconomic deprivation for each patient’s neighborhood. The outcome variables related to compliance included the quantity of no-show visits at the orthopaedic clinic and delays in follow-up care of >1 week. Risk factors for suboptimal compliance were evaluated by bivariate analysis and multivariate logistic regression.

Results:

The cohort included 457 adolescents; 75.9% of the patients were male, and the median age was 16.1 years. The median ADI was 101.5 points (interquartile range, 86.3 to 114.9 points). Bivariate analyses demonstrated that higher ADI, black race, single-parent caregiver status, Medicaid insurance, non-sports mechanisms of injury, and surgical management are associated with suboptimal fracture care compliance. Adolescents from the most socially deprived regions were significantly more likely to have delays in care (33.8% compared with 20.1%; p = 0.037) and miss scheduled orthopaedic visits (29.9% compared with 7.1%; p < 0.001) compared with adolescents from the least deprived regions. ADI, Medicaid insurance, and initial presentation to the emergency department were independent predictors of suboptimal care compliance, when controlling for other variables.

Conclusions:

Socioeconomic deprivation is associated with an increased risk of suboptimal fracture care compliance in adolescents. Clinicians can utilize caregiver and insurance status to better understand the likelihood of fracture care compliance. These findings highlight the importance of understanding differences in each family’s ability to adhere to the recommended follow-up and of implementing measures to enhance compliance.

Evolution of concentricity after closed reduction in developmental dysplasia of the hip

AIMS

The goal of closed reduction (CR) in the treatment of developmental dysplasia of the hip (DDH) is to achieve and maintain concentricity of the femoral head in the acetabulum. However, concentric reduction is not immediately attainable in all hips and it remains controversial to what degree a non-concentric reduction is acceptable. This prospective study is aimed at investigating the dynamic evolution of the hip joint space after CR in DDH using MRI.

METHODS

A consecutive series of patients with DDH who underwent CR since March 2014 were studied. Once the safety and stability were deemed adequate intraoperatively, reduction was accepted regardless of concentricity. Concentricity was defined when the superior joint space (SJS) and medial joint space (MJS) were both less than 2 mm, based on MRI. A total of 30 children, six boys and 24 girls, involving 35 hips, were recruited for the study. The mean age at CR was 13.7 months (3.5 to 27.6) and the mean follow-up was 49.5 months (approximately four years) (37 to 60). The joint space was evaluated along with the interval between the inverted and everted limbus.

RESULTS

Only three hips (8.6%) were fully concentric immediately after CR. During follow-up, 24 hips (68.6%) and 27 hips (77.1%) became concentric at six months and one year, respectively. Immediate SJS after CR decreased from 3.51 mm to 0.79 mm at six months follow-up (p = 0.001). SJS in the inverted group decreased from 3.75 mm to 0.97 mm at six months follow-up. SJS or MJS in the everted group were less than those in the inverted group at each time of follow-up (p = 0.008, p = 0.002).

CONCLUSION

A stable, safe but non-concentric reduction achieved before the age of two years appears to improve over time with nearly 80% of hips becoming fully concentric by one year. Cite this article: Bone Joint J 2020;102-B(5):618-626.

Predicting subsequent contralateral slipped capital femoral epiphysis: an evidence-based approach

PURPOSE

The purpose of this study was to identify risk factors for developing a subsequent contralateral slipped capital femoral epiphysis (SCFE) and provide a prediction score to quantify risk of subsequent slip at the time of initial presentation.

METHODS

This retrospective study included patients that presented with a unilateral SCFE between 2006 and 2017. Chart and radiographic review were performed to collect demographic, clinical and radiographic risk factors. Descriptive statistics, univariate analyses and multivariate regression analysis were used to compare risk factors between patients that did or did not develop a subsequent contralateral SCFE.

RESULTS

This study included 183 patients and 33 patients (18%) developed a subsequent contralateral SCFE. Younger age at time of initial presentation, lower modified Oxford Score and smaller difference in epiphyseal-diaphyseal angle between both sides during index presentation were significant predictors of subsequent contralateral SCFE. Specifically, age ≤ 11 years, modified Oxford Score ≤ 20 and difference in epiphyseal-diaphyseal angle of ≤ 21° between both hips were predictive of a contralateral slip (Area Under the Curve = 0.78; p < 0.05). The presence of each risk factor increased the risk of subsequent contralateral SCFE and having all three risk factors increased the risk to 73%.

CONCLUSION

There is a significant risk of subsequent contralateral SCFE in patients with unilateral SCFE, and predictive risk factors include younger age, lower modified Oxford Score and smaller difference in epiphyseal-diaphyseal angle between the affected and unaffected hips.

LEVEL OF EVIDENCE

Level III.

Septic Arthritis of the Hip in Children: A Critical Analysis Review

Septic arthritis of the hip is a common and potentially devastating condition in children. Septic arthritis is most commonly caused by Staphylococcus aureus, but other pathogens should be considered on the basis of patient age and presence of risk factors. Diagnosis of septic arthritis is based on history and physical examination, laboratory tests, radiographs, ultrasound, and arthrocentesis. Treatment comprises empiric antibiotics and joint debridement, and antibiotics are subsequently tailored on the basis of culture data, local resistance patterns, and clinical response. Late sequelae of septic arthritis include osteonecrosis, chondrolysis, growth disturbance, subluxation or dislocation, and progressive ankylosis. Surgical treatments to address these issues have been described.

Intraoperative Contrast-Enhanced Ultrasound Imaging of Femoral Head Perfusion in Developmental Dysplasia of the Hip: A Feasibility Study

OBJECTIVES

Developmental dysplasia of the hip (DDH) is one of the most common developmental deformities of the lower extremity. Although many children are successfully treated with a brace or harness, some require intraoperative closed or open reduction and spica casting. Surgical reduction is largely successful to relocate the hip; however, iatrogenic avascular necrosis is a major source of morbidity. Recent research showed that postoperative gadolinium-enhanced magnetic resonance imaging (MRI) can depict hip perfusion, which may predict a future incidence of avascular necrosis. As contrast-enhanced ultrasound (CEUS) assesses blood flow in real time, it may be an effective intraoperative alternative to evaluate femoral head perfusion. Here we describe our initial experience regarding the feasibility of intraoperative CEUS of the hip for the assessment of femoral head perfusion before and after DDH reduction.

METHODS

This single-institution retrospective Institutional Review Board-approved study with a waiver of informed consent evaluated intraoperative hip CEUS in children with DDH compared to postoperative contrast-enhanced MRI. Pediatric radiologists, blinded to prior imaging findings and outcomes, reviewed both CEUS and MRI examinations separately and some time from the initial examination both independently and in consensus.

RESULTS

Seventeen patients had 20 intraoperative CEUS examinations. Twelve of 17 (70.6%) had prereduction hip CEUS, postreduction hip CEUS, and postreduction gadolinium-enhanced MRI. Seven of 12 (58.3%) were evaluable retrospectively. All CEUS studies showed blood flow in the femoral epiphysis before and after reduction, and all MRI studies showed femoral head enhancement after reduction. The CEUS and MRI for all 7 patients also showed physeal blood flow.

CONCLUSIONS

Contrast-enhanced ultrasound is a feasible intraoperative tool for assessing adequate blood flow after hip reduction surgery in DDH.

Utility of Perioperative Laboratory Tests in Pediatric Patients Undergoing Spinal Fusion for Scoliosis

STUDY DESIGN

Retrospective comparative study.

OBJECTIVES

We aimed to characterize the frequency of perioperative laboratory tests for posterior spinal fusion (PSF) for adolescent idiopathic scoliosis (AIS) and to assess whether test results affected clinical management.

SUMMARY OF BACKGROUND DATA

Perioperative laboratory tests for PSF including complete blood count, coagulation laboratory tests, basic metabolic panels (BMPs), and type and screen, are commonly ordered based on providers' discretion or existing order sets. Studies have shown unnecessary laboratory tests as financially and physically costly in adults; however, no studies have examined the necessity of common perioperative laboratory tests in pediatric spinal deformity surgery.

METHODS

Retrospective review of patients aged 10-18 years who underwent PSF for AIS at our center in the past three years. The clinical utility of perioperative laboratory tests was assessed based on detected incidence of anemia, blood transfusions, hematology/endocrinology/nephrology consultations, insulin administration, and postponed/canceled surgeries.

RESULTS

A total of 234 patients were included (mean age 14.4 ± 1.8 years, 75% female). Of 105 (44.9%) patients with preoperative coagulation laboratory tests, 21 (20%) had abnormal results; however, none had subsequent hematology consultations or canceled/postponed surgeries. Postoperatively, only 5 (2.1%) patients and 30 (12.8%) patients had hemoglobin values less than 8 g/dL on postoperative day (POD) 1 and 2, respectively. Multivariate analysis identified POD1 hemoglobin ≤9.35 g/dL as the only predictor of hemoglobin <8 g/dL on POD2. Overall, there were 8 (3.4%) indicated blood transfusions postoperatively. Costs of unnecessary laboratory tests averaged $95.27 (range $49.72 to $240.27) per patient.

CONCLUSIONS

Many perioperative laboratory orders may be unnecessary in pediatric spinal deformity surgery, subjecting patients to extraneous costs and needlesticks. In particular, preoperative coagulation laboratory tests, perioperative BMPs, and additional postoperative CBCs for those with hemoglobin >9.35 on POD1 may not be warranted.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

Imaging of developmental dysplasia of the hip: ultrasound, radiography and magnetic resonance imaging

Developmental dysplasia of the hip (DDH) describes a broad spectrum of developmental abnormalities of the hip joint that are traditionally diagnosed during infancy. Because the development of the hip joint is a dynamic process, optimal treatment depends not only on the severity of the dysplasia, but also on the age of the child. Various imaging modalities are routinely used to confirm suspected diagnosis, to assess severity, and to monitor treatment response. For infants younger than 4 months, screening hip ultrasound (US) is recommended only for those with risk factors, equivocal or positive exam findings, whereas for infants older than 4-6 months, pelvis radiography is preferred. Following surgical hip reduction, magnetic resonance (MR) imaging is preferred over computed tomography (CT) because MR can not only confirm concentric hip joint reduction, but also identify the presence of soft-tissue barriers to reduction and any unexpected postoperative complications. The routine use of contrast-enhanced MR remains controversial because of the relative paucity of well-powered and validated literature. The main objectives of this article are to review the normal and abnormal developmental anatomy of the hip joint, to discuss the rationale behind the current recommendations on the most appropriate selection of imaging modalities for screening and diagnosis, and to review routine and uncommon findings that can be identified on post-reduction MR, using an evidence-based approach. A basic understanding of the physiology and the pathophysiology can help ensure the selection of optimal imaging modality and reduce equivocal diagnoses that can lead to unnecessary treatment.

Ultrasound Characteristics of Clinically Dislocated But Reducible Hips With DDH

BACKGROUND

Although ultrasound (US) is frequently used in diagnosis and management of infantile developmental dysplasia of the hip, precise ultrasonographic parameters of what constitutes a dislocation, subluxation etc remain poorly defined. The purpose of this study was (1) to describe the ultrasonographic characteristics of a large cohort of clinically dislocated but reducible hips and (2) to begin to develop ultrasonographic definitions for what constitutes a hip dislocation.

METHODS

A retrospective review of prospectively collected data from an international multicenter study group on developmental dysplasia of the hip was conducted on all patients under 6 months of age with hip(s) that were dislocated at rest but reducible based on initial physical examination (ie, Ortolani positive). Femoral head coverage (FHC), alpha angle (α), and beta angle (β) were measured on pretreatment US by the individual treating surgeon, and were recorded directly into the database.

RESULTS

Based on 325 Ortolani positive hips, the median FHC on presentation was 10% with an interquartile range of 0% to 23%. A total of 126 of the 327 hips (39%) demonstrated 0% FHC. The 90th percentile was found to be at 33% FHC. Of 264 hips with sufficient α data, the median α was 43 degrees with an interquartile range from 37 to 49 degrees. The 90th percentile for α was at 54 degrees. A total of 164 hips had documented β with a median of 66 degrees and an interquartile range of 57 to 79 degrees; the 90th percentile was at 94 degrees.

CONCLUSIONS

Analysis of a large cohort of patients with dislocated but reducible hips reveals a median percent FHC of 10%, a median α of 43 degrees, and a median β of 66 degrees on initial US. Using a threshold at the 90th percentile, a sensible ultrasonographic definition of a dislocated hip seems to be FHC≤33%, implying that FHC between 34% and 50% may be reasonably termed a subluxation. Although these findings are consistent with previous, smaller reports, further prospective research is necessary to validate these thresholds.

LEVEL OF EVIDENCE

Level IV-diagnostic study.

Bone Remodeling and Disc Morphology in the Distal Unfused Spine After Spinal Fusion in Adolescent Idiopathic Scoliosis

BACKGROUND

Morphologic changes in the vertebral body in adolescent idiopathic scoliosis (AIS) have been associated with curve development and progression. Yet, after an AIS spinal surgery, the impact of the global and local spinal realignment on the vertebral body and intervertebral disc morphologic changes, particularly in the distal unfused spine, have not been determined.

QUESTIONS/PURPOSES

To determine the changes in the unfused lumbar vertebrae and disc morphology two years after spinal fusion in AIS patients undergoing selective thoracic fusion (STF).

PATIENTS AND METHODS

A total of 58 patients with Lenke type 1 AIS who underwent STF with a minimum two-year follow-up and 20 nonscoliotic adolescents were included. Biplanar stereoradiography of the spine at preoperative, early postoperative, and two-year follow-up were used to generate 3D models of the spine. Lumbar spine vertebral and intervertebral heights (anterior, posterior, left, and right) and the degree of wedging in the frontal and sagittal plane were calculated in the local coordinate system of the vertebral bodies. The morphology of vertebrae and discs were compared between the pre- and postoperative visits of AIS patients and nonscoliotic controls.

RESULTS

Lumbar lordosis was not statistically different between the pre- and post-operative AIS and controls, p > .05. The contribution of the lumbar vertebral bodies and discs' sagittal wedging to the total L1-L5 lordosis were 20% and 80%, respectively, for nonscoliotic controls and 61% and 39%, respectively, for AIS patients at two-year follow-up. The decrease in the anterior and left heights of the disc between the preoperative and two-year follow-up was significant, p < .05.

CONCLUSION

Patients undergoing STF for Lenke 1 AIS are able to achieve normal lumbar lordosis after surgery but seem to regain their sagittal alignment by morphologic changes in the disc more so than the vertebral body. A larger contribution of the vertebral sagittal wedging to the total lumbar lordosis at two years post STF was observed when these variables were compared to the nonscoliotic adolescents.

LEVEL OF EVIDENCE

Level IV.

Operative Reduction for Developmental Dysplasia of the Hip: Epidemiology Over 16 Years

BACKGROUND

The burden of surgical treatment for infantile developmental dysplasia of the hip (DDH) is unknown. We aimed to investigate the epidemiology of operative DDH reductions in the United States and identify potential at-risk populations.

METHODS

The Healthcare Utilization Project Kids' Inpatient Database (1997 to 2012) were analyzed. International Classification of Diseases (ICD-9) codes identified inpatient hospitalizations for DDH reductions excluding neuromuscular cases. Hospital variables and patient demographics were captured. Weighted population-level counts were calculated to allow for national estimates.

RESULTS

An estimated 5525 (95% confidence interval, 4907.8-6142.2) operative reductions were performed. In total, 73.3% were open with a mean age at the reduction of 2.3 years (95% confidence interval, 2.1-2.5). In total, 70.0% were female and 42.3% were white. Regional distribution varied: 36.4% of reductions occurred in the West, 22.8% in the South, 21.9% in the Midwest, and 18.9% in the Northeast. Operative reductions decreased over time; open reductions decreased by 5.6% and closed by 53.4%. Mean age at treatment increased from 1.6 to 3.7 years (P<0.001). On multivariate analysis, age (P<0.001) and geographic location (P<0.05) were associated with open reduction. Patients in the West had increased odds of being Hispanic or Asian/Pacific Islander [odds ratio (OR), 4.9, P<0.001 and OR, 2.8; P=0.008]. In the South and Midwest, the highest income quartile was protective (OR, 0.4; P=0.001 and OR, 0.5; P=0.018).

CONCLUSIONS

The frequency of closed reductions decreased more over time compared with open reductions. However, the mean age of children undergoing reductions increased suggesting a possible delay in diagnosis. The data suggests that there is room for improvement in screening. Targeted research in identified populations may reduce the burden of surgical disease in infantile DDH.

LEVEL OF EVIDENCE

Level III.

A Dedicated Pediatric Spine Deformity Team Significantly Reduces Surgical Time and Cost

BACKGROUND

As high-quality health care becomes increasingly expensive, improvement projects are focused on reducing cost and increasing value. To increase value by reducing operating room (OR) utilization, we studied the effect of a dedicated team approach for posterior spinal fusion (PSF) for scoliosis.

METHODS

With institutional support, an interdisciplinary, dedicated team was assembled. Members developed standardized protocols for anesthetic management and patient transport, positioning, preparation, draping, imaging, and wake-up. These protocols were initially implemented with a small interdisciplinary team, including 1 surgeon (Phase 1), and then were expanded to include a second surgeon and additional anesthesiology staff (Phase 2). We compared procedures performed with a dedicated team (the Dedicated Team cases) and procedures performed without a such a team (the Casual Team cases). Because of the heterogeneous nature of PSF for scoliosis, we developed a case categorization system: Category 1 was relatively homogeneous and indicated patients with fusion of ≤12 levels, no osteotomies, and a body mass index (BMI) of <25 kg/m, and Category 2 was more heterogeneous and indicated patients with fusion of >12 levels and/or ≥1 osteotomy and/or a BMI of ≥25 kg/m.

RESULTS

In total, 89 Casual Team and 78 Dedicated Team cases were evaluated: 71 were in Category 1 and 96 were in Category 2. Dedicated Team cases used significantly less OR time for both Categories 1 and 2 (p < 0.001). In Category-1 cases, the average reduction was 111.4 minutes (29.7%); in Category-2 cases, it was 76.9 minutes (18.5%). The effect of the Dedicated Team was scalable: the reduction in OR time was significant in both Phase 1 and Phase 2 (p < 0.001). The Dedicated Team cases had no complications. Cost reduction averaged approximately $8,900 for Category-1 and $6,000 for Category-2 cases.

CONCLUSIONS

By creating a dedicated team and standardizing several aspects of PSFs for scoliosis, we achieved a large reduction in OR time. This increase in team efficiency was significant, consistent, and scalable. As a result, we can routinely complete 2 Category-1 PSFs in the same OR with the same team without exceeding standard block time.

Skeletal muscle and plasma concentrations of cefazolin during complex paediatric spinal surgery

BACKGROUND

Surgical site infections (SSIs) can have devastating consequences for children who undergo spinal instrumentation. Prospective evaluations of prophylactic cefazolin in this population are limited. The purpose of this study was to describe the pharmacokinetics and skeletal muscle disposition of prophylactic cefazolin in a paediatric population undergoing complex spinal surgery.

METHODS

This prospective pharmacokinetic study included 17 children with adolescent idiopathic scoliosis undergoing posterior spinal fusion, with a median age of 13.8 [interquartile range (IQR) 13.4-15.4] yr and a median weight of 60.6 (IQR 50.8-66.0) kg. A dosing strategy consistent with published guidelines was used. Serial plasma and skeletal muscle microdialysis samples were obtained during the operative procedure and unbound cefazolin concentrations measured. Non-compartmental pharmacokinetic analyses were performed. The amount of time that the concentration of unbound cefazolin exceeded the minimal inhibitory concentration for bacterial growth for selected SSI pathogens was calculated.

RESULTS

Skeletal muscle concentrations peaked at a median of 37.6 (IQR 26.8-40.0) µg ml(-1) within 30-60 min after the first cefazolin 30 mg kg(-1) dose. For patients who received a second 30 mg kg(-1) dose, the peak concentrations reached a median of 40.5 (IQR 30.8-45.7) µg ml(-1) within 30-60 min. The target cefazolin concentrations for SSI prophylaxis for meticillin-sensitive Staphylococcus aureus (MSSA) and Gram-negative pathogens were exceeded in skeletal muscle 98.9 and 58.3% of the intraoperative time, respectively.

CONCLUSIONS

For children with adolescent idiopathic scoliosis undergoing posterior spinal fusion, the cefazolin dosing strategy used in this study resulted in skeletal muscle concentrations that were likely not to be effective for intraoperative SSI prophylaxis against Gram-negative pathogens.

What's New in Pediatric Hip?

BACKGROUND

Developmental dysplasia of the hip (DDH), which encompasses a wide spectrum of disease from mild dysplasia to frank dislocation, is one of the most common developmental deformities of the lower extremities and one of the leading causes of future osteoarthritis and hip arthroplasty. Legg-Calvé-Perthes disease (LCPD) results from a vascular insult to the growing femoral epiphysis, which in turn can create permanent morphologic changes to the hip joint. Slipped capital femoral epiphysis (SCFE) occurs when the proximal femoral physis fails allowing the epiphysis to displace in relation to the metaphysis. Infections about the hip also create significant morbidity in the pediatric hip.

METHODS

We searched the PubMed database for all studies related to DDH, LCPD, SCFE, and pediatric hip infections that were published between July 1, 2014 and August 31, 2017. The search was limited to English articles and yielded 839 papers. This project was initiated by the Pediatric Orthopaedic Society of North America Publications Committee and was reviewed and approved by the Pediatric Orthopaedic Society of North America Presidential Line.

RESULTS

A total of 40 papers were selected for review based upon new and significant findings. Select historical manuscripts are also included to provide sufficient background information.

CONCLUSIONS

DDH, LCPD, SCFE, and infections about the hip continue to be important topics in pediatric orthopaedics and areas of vital research. This manuscript reviews the most important recent literature on the diagnosis and treatment of these pediatric hip conditions.

LEVEL OF EVIDENCE

Level V.

Distinguishing Pediatric Lyme Arthritis of the Hip from Transient Synovitis and Acute Bacterial Septic Arthritis: A Systematic Review and Meta-analysis

Objective

Lyme arthritis is an increasingly recognized clinical entity that often prompts orthopaedic evaluation in pediatric patients. While Lyme arthritis is most common in the knee, the clinical presentation of Lyme arthritis of the hip can be similar to both acute bacterial septic arthritis and transient synovitis. Accurately distinguishing these clinical entities is important since the definitive treatment of each is distinct. Because there is limited literature on monoarticular Lyme arthritis of the hip, the purpose of this study was to perform a systematic review and meta-analysis of clinical and laboratory parameters associated with Lyme arthritis (LA) of the hip and compare them to septic arthritis (SA) and transient synovitis (TS). 

Study design

A systematic review of the literature was performed using the following search terms, including the variants and plural counterparts “hip” and “Lyme arthritis.” A final database of individual patients was assembled from the published literature and direct author correspondence, when available. A previously published cohort of patients with hip transient synovitis or septic arthritis was used for comparative analysis. A comparative statistical analysis was performed to the assembled database to assess differences in laboratory and clinical variables between the three diagnoses. 

Results

Data on 88 patients diagnosed with Lyme arthritis of the hip was collected and consolidated from the 12 articles meeting inclusion criteria. The average age of patients presenting with Lyme arthritis was 7.5 years (± 3.5 years), the mean erythrocyte sedimentation rate (ESR), and the C-reactive protein (CRP) was 41 mm/hr and 3.9 mg/L, respectively. Peripheral white blood cell (WBC) count averaged 10.6 x 10⁹cells/L with the synovial WBC count averaging 55,888 cells/mm³. Compared to a previous cohort of patients with confirmed transient synovitis or septic arthritis, the 95% confidence interval for ESR was 21 - 33 mm/hr in those diagnosed with toxic synovitis (TS), 37 - 46 mm/hr for Lyme arthritis (LA), and 44 - 64 mm/hr for septic arthritis (SA). Synovial WBC counts (cells/mm³) 95% confidence intervals (CI) were 5,644 - 15,388 cells/mm³ for TS, 47,533 - 64,242 cells/mm³ for LA, and 105,432 - 260,214 cells/mm³ for SA. There was a statistically significant difference in the incidence of fever > 38.5^oC (P < 0.001) and refusal to bear weight (P < 0.01) between SA, LA, and TS.

Conclusions

Monoarticular Lyme arthritis can be a cause of hip pain in certain geographic areas and has clinical and diagnostic overlap with transient synovitis and acute bacterial septic arthritis. This study consolidates the available literature and represents the largest series of patients diagnosed with Lyme arthritis of the hip to date. We propose a diagnostic algorithm that serially incorporates ESR, followed by a synovial neutrophil count, when evaluating pediatric patients with an irritable hip in Lyme endemic areas. 

Does Surgeon Experience Impact the Risk of Complications After Bernese Periacetabular Osteotomy?

BACKGROUND

Bernese periacetabular osteotomy (PAO) is a technically challenging procedure with potential risk for major complications and a previously reported steep learning curve. However, the impact of contemporary hip preservation fellowships on the learning curve of PAO has not been established.

QUESTIONS/PURPOSES

(1) What was the frequency of major complications during the PAO learning curve of two surgeons who recently graduated from hip preservation fellowships? (2) Is increasing level of experience associated with the risk of a complication and with operative time, a possible surrogate measure of surgical performance?

METHODS

We retrospectively studied 81 PAOs performed by one of two surgeons who recently graduated from a hip preservation fellowship during their first 4 years of practice in two institutions. One of the surgeons participated as a fellow in 78 PAOs with an increasing level of responsibility during the course of 1 full year. The other surgeon performed 41 PAOs as a fellow during 6 months, also with an increasing level of responsibility during that time. There were 68 (84%) female and 13 (16%) male patients (mean age, 18 years; range, 10-36 years). The frequency of complications was recorded early and at 1 year after surgery and graded according to a validated classification system describing five grades of complications. Complications that required surgical intervention (Grade III) and life-threatening complications (Grade IV) were considered major complications. Persistent pain after surgery, although considered a failure of PAO, was not considered a surgical complication as a result of the multifactorial etiology of pain after hip-preserving surgery. However, early reoperation and revision surgery were counted as complications. To evaluate the association between increasing level of experience and the occurrence of complications, we divided each surgeon's experience into his first 20 procedures (initial interval) and his second 20 (experienced interval) to test whether the incidence of complications or operative time was different between the two intervals. Because the association between experience and the likelihood of a complication was estimated to be consistent between the two surgeons, the analysis was performed with data pooled from the two surgeons. To test whether there was a difference in the likelihood of a complication in the initial and the experienced intervals, a multivariate logistic regression analysis was performed and the adjusted risk of a complication between the two intervals was calculated. Linear regression analyses were used to test the association between surgeon level of experience and operative time.

RESULTS

The overall incidence of major (Grade III or Grade IV) complications was 6% (95% confidence interval [CI], 2%-14%). These included deep infection (3% [three of 81]), intraoperative posterior column fracture (1% [one of 81]), and pulmonary embolism (1% [one of 81]). With the numbers available, the risk of a complication did not decrease with increasing surgeon experience. After controlling for body mass index and surgeon, the frequency of a complication did not decrease in the experienced interval relative to the initial interval (odds ratio, 0.78; 95% CI, 0.25-2.4; p = 0.6623). The adjusted risk difference between the experienced interval relative and the initial interval was 6% (95% CI, -11% to 23%). When experience was modeled as a continuous variable (number of PAOs performed), increasing experience was not associated with a lower likelihood of a complication (odds ratio per one PAO increase in experience, 0.99; 95% CI, 0.94-1.04; p = 0.5478). However, after adjusting for body mass index and surgeon, increased experience was associated with a reduction in operative time (slope [change in log operative time per one procedure increase in experience], -0.005; 95% CI, -0.009 to -0.0005; p = 0.0292). For every one additional PAO increase in experience, there was a 0.45% decrease in operative time (95% CI, 0.05%-0.86% decrease].

CONCLUSIONS

With a case exposure greater than 40 PAOs and progressive surgical responsibility during contemporary structured training, two young surgeons were able to perform PAO with a low risk of complications. However, even with that surgical experience before independent practice, surgical time decreased over the first 40 PAOs they performed independently. Our data may help guide orthopaedic residency and hip preservation fellowship programs in establishing training requirements and assessing competency in PAO.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Traumatic pelvic fractures in children and adolescents

Although traumatic pelvic fractures in children are relatively rare, these injuries are identified in about 5% of children admitted to level 1 trauma centers after blunt trauma.^1-4 Such injuries differ from adult pelvic fractures in important ways and require distinct strategies for management. While the associated mortality rate for children with pelvic fractures is much lower than that for adults, the patient may require urgent surgical intervention for associated life-threatening injuries such as head trauma and abdominal injury. Unstable pelvic ring fractures should be acutely managed using an initial approach similar to that used in adult orthopedic traumatology. Although very few pediatric pelvic fractures will ultimately need surgical treatment, patients with these injuries must be followed over time to confirm proper healing, ensure normal pelvic growth, and address any potential complications. The trauma team suspecting a pelvic fracture in a child must understand the implication of such a finding, identify fracture patterns that increase suspicion of associated injuries, and involve pediatric or adult orthopedic specialists as appropriate during the management of the patient.

A Dedicated Orthopaedic Trauma Operating Room Improves Efficiency at a Pediatric Center

BACKGROUND

Dedicated orthopaedic trauma operating rooms have improved operating room efficiency, physician schedules, and patient outcomes in adult populations. The purpose of this study was to determine if a dedicated orthopaedic trauma operating room was associated with improved patient flow and cost savings at a level-I pediatric trauma center.

METHODS

A retrospective analysis was performed for two 3-year intervals before and after implementation of a weekday, unbooked operating room reserved for orthopaedic trauma cases. Index procedures for 5 common fractures were investigated, including supracondylar humeral fractures, both bone forearm fractures, lateral condylar fractures, tibial fractures, and femoral fractures. To provide a control group to account for potential extrinsic changes in hospital efficiency, laparoscopic appendectomies were also analyzed. For each procedure, efficiency parameters and surgical complications, defined as unplanned reoperations, were compared between time periods. The mean cost reduction per patient was calculated on the basis of the mean daily cost of an inpatient hospital bed.

RESULTS

Of 1,469 orthopaedic procedures analyzed, 719 cases occurred before the implementation of the dedicated orthopaedic trauma operating room, and 750 cases were performed after the implementation. The frequency of after-hours procedures (5 P.M. to 7 A.M.) was reduced by 48% (p < 0.001). The mean wait time for the operating room decreased among supracondylar humeral fractures, lateral condylar fractures, and tibial fractures, whereas no significant decrease (p = 0.302) occurred among 2,076 laparoscopic appendectomy cases. The mean duration of the surgical procedure and the mean time in the operating room were not significantly affected. Across all orthopaedic procedures, the mean duration of inpatient hospitalization decreased by 5.6 hours (p < 0.001), but no significant difference occurred among appendectomies. Decreased length of stay resulted in a mean cost reduction of $1,251 per patient. Supracondylar humeral fracture cases performed after implementation of the dedicated orthopaedic trauma operating room had fewer surgical complications (p = 0.018). No difference in complication rate was detected among the other orthopaedic procedures.

CONCLUSIONS

A dedicated orthopaedic trauma operating room in a pediatric trauma center was associated with fewer after-hours procedures, decreased wait time to the surgical procedure, reduced length of hospitalization, and decreased cost.

Evaluation of Brace Treatment for Infant Hip Dislocation in a Prospective Cohort: Defining the Success Rate and Variables Associated with Failure

BACKGROUND

The use of a brace has been shown to be an effective treatment for hip dislocation in infants; however, previous studies of such treatment have been single-center or retrospective. The purpose of the current study was to evaluate the success rate for brace use in the treatment of infant hip dislocation in an international, multicenter, prospective cohort, and to identify the variables associated with brace failure.

METHODS

All dislocations were verified with use of ultrasound or radiography prior to the initiation of treatment, and patients were followed prospectively for a minimum of 18 months. Successful treatment was defined as the use of a brace that resulted in a clinically and radiographically reduced hip, without surgical intervention. The Mann-Whitney test, chi-square analysis, and Fisher exact test were used to identify risk factors for brace failure. A multivariate logistic regression model was used to determine the probability of brace failure according to the risk factors identified.

RESULTS

Brace treatment was successful in 162 (79%) of the 204 dislocated hips in this series. Six variables were found to be significant risk factors for failure: developing femoral nerve palsy during brace treatment (p = 0.001), treatment with a static brace (p < 0.001), an initially irreducible hip (p < 0.001), treatment initiated after the age of 7 weeks (p = 0.005), a right hip dislocation (p = 0.006), and a Graf-IV hip (p = 0.02). Hips with no risk factors had a 3% probability of failure, whereas hips with 4 or 5 risk factors had a 100% probability of failure.

CONCLUSIONS

These data provide valuable information for patient families and their providers regarding the important variables that influence successful brace treatment for dislocated hips in infants.

LEVEL OF EVIDENCE

Prognostic Level I. See Instructions for Authors for a complete description of levels of evidence.

A Rapid Recovery Pathway for Adolescent Idiopathic Scoliosis That Improves Pain Control and Reduces Time to Inpatient Recovery After Posterior Spinal Fusion

STUDY DESIGN

Retrospective comparative cohort.

OBJECTIVES

To determine if a standardized multimodal analgesic and rehabilitation protocol (rapid recovery pathway [RRP]) in adolescent idiopathic scoliosis (AIS) patients undergoing posterior spinal fusion (PSF) could improve pain control, reduce opioid-related complications, and expedite early mobilization.

BACKGROUND

Several reports have described postoperative recovery pathways for AIS patients undergoing PSF that shorten length of stay (LOS) without reporting the impact such pathways might have on patients' pain or quality of recovery.

METHODS

We compared two high-volume surgeons' patients managed on our conventional pathway (CP) or our RRP. The CP analgesia consisted of intraoperative methadone and postoperative patient-controlled analgesia (PCA) until tolerating oral analgesics, with adjunctive diazepam. Analgesia on the RRP includes intraoperative methadone and postoperative PCA; patients also receive preoperative gabapentin and acetaminophen, intraoperative intravenous acetaminophen, and postoperative diazepam, gabapentin, acetaminophen, and ketorolac. Ambulation and full diet are permitted beginning postoperative day 1. The primary outcome was mean daily pain scores. Secondary outcomes were LOS, time to pathway milestone completions, and frequency of opioid-related side effects requiring treatment.

RESULTS

There were 58 patients in the RRP group and 80 patients in the CP group. Patients on RRP had improved mean daily pain scores on postoperative days 0 (p = .027), 1 (p < .001) and 2 (p = .004). RRP patients were discharged home 31% earlier, discontinued from PCA 34% earlier and had their urinary catheters removed 26% earlier. Total opioid consumption decreased on postoperative day 0 (p < .001), but not postoperative day 1 (p = .773) or 2 (p = .343). Fewer patients on the RRP required medication for opioid-induced pruritus (p = .001), but there was no difference in the frequency of odansetron administration (p = .566). There were no differences in 30-day rates of readmission (p = .407).

CONCLUSION

Implementation of standardized RRP resulted in reduced pain, faster mobilization, reduced frequency of opioid-related side-effects, and earlier discharge.

Predictive Factors for Differentiating Between Septic Arthritis and Lyme Disease of the Knee in Children

BACKGROUND

Differentiating between septic arthritis and Lyme disease of the knee in endemic areas can be challenging and has major implications for patient management. The purpose of this study was to identify a prediction rule to differentiate septic arthritis from Lyme disease in children presenting with knee pain and effusion.

METHODS

We retrospectively reviewed the records of patients younger than 18 years of age with knee effusions who underwent arthrocentesis at our institution from 2005 to 2013. Patients with either septic arthritis (positive joint fluid culture or synovial white blood-cell count of >60,000 white blood cells/mm(3) with negative Lyme titer) or Lyme disease (positive Lyme immunoglobulin G on Western blot analysis) were included. To avoid misclassification bias, undiagnosed knee effusions and joints with both a positive culture and positive Lyme titers were excluded. Historical, clinical, and laboratory data were compared between groups to identify variables for comparison. Binary logistic regression analysis was used to identify independent predictive variables.

RESULTS

One hundred and eighty-nine patients were studied: 23 with culture-positive septic arthritis, 26 with culture-negative septic arthritis, and 140 with Lyme disease. Multivariate binary logistic regression identified pain with short arc motion, history of fever reported by the patient or a family member, C-reactive protein of >4 mg/L, and age younger than 2 years as independent predictive factors for septic arthritis. A simpler model was developed that showed that the risk of septic arthritis with none of these factors was 2%, with 1 of these factors was 18%, with 2 of these factors was 45%, with 3 of these factors was 84%, or with all 4 of these factors was 100%.

CONCLUSIONS

Although septic arthritis of the knee and Lyme monoarthritis share common features that can make them difficult to distinguish clinically, the presence of pain with short arc motion, C-reactive protein of >4.0 mg/L, patient-reported history of fever, and age younger than 2 years were independent predictive factors of septic arthritis in pediatric patients. The more factors that are present, the higher the risk of having septic arthritis.

LEVEL OF EVIDENCE

Diagnostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Does Perfusion MRI After Closed Reduction of Developmental Dysplasia of the Hip Reduce the Incidence of Avascular Necrosis?

BACKGROUND

Gadolinium-enhanced perfusion MRI (pMRI) after closed reduction/spica casting for developmental dysplasia of the hip (DDH) has been suggested as a potential means to identify and avoid avascular necrosis (AVN). To date, however, no study has evaluated the effectiveness of pMRI in clinical practice or compared it with other approaches (such as postreduction CT scan) to show a difference in the proportion of AVN.

QUESTIONS/PURPOSES

(1) Can a pMRI-based protocol be used immediately post closed reduction to minimize the risk that AVN would develop? (2) What are the overall hip-related outcomes after closed reduction/spica casting using this protocol? (3) Do any patient-specific factors at the time of closed reduction predict future AVN?

METHODS

This was a retrospective cohort study at a large tertiary care children's hospital. Between 2009 and 2013 we treated 43 patients with closed reduction/spica casting for DDH, of whom 33 (77%) received a postreduction pMRI. All patients were indicated for pMRI per treating surgeon preference. A convenience sample totaling 25 hips in 22 patients treated with pMRI was then established using the following exclusion criteria: DDH of neuromuscular/syndromic origin, failed initial closed reduction, less than 1 year of clinical and radiographic followup, and subsequent open reduction. Next, the 40 patients treated with closed reduction between 2004 and 2009 were screened until the chronologically most recent 25 hips (after applying the previously mentioned exclusion criteria) were identified in 21 of the first 34 patients (62%) screened. Although termed the CT group, specific postreduction imaging was not a defined inclusion criterion in this group with the majority (21 of 25 [84%]) receiving postreduction CT and the remainder (four of 25 [16%]) receiving only postreduction radiographs. All hips with globally decreased femoral head perfusion on postreduction pMRI were treated with immediate cast removal followed by repeat closed reduction or open reduction, as per surgeon preference, with two of 33 (6%) requiring such further interventions. Salter criteria were then used to determine the proportion of AVN on radiographs at 1-year and final followup. Secondary outcomes including residual dysplasia and the need for further corrective surgery were ascertained through radiographic and retrospective chart review.

RESULTS

At 1-year followup there was no difference in the proportion of AVN in the historical CT group as compared with the pMRI group (six of 25 [24%] versus one of 25 [4%]; odds ratio [OR], 7.6; 95% confidence interval [CI], 0.8-363; p = 0.098). However, by final followup there was a statistically higher proportion of AVN in the CT group (seven of 25 [28%] versus one of 25 [4%]; OR, 9.3; 95% CI, 1.0-438; p = 0.049). No patient with normal perfusion on postreduction pMRI went on to develop AVN. In those pMRI patients in whom a successful reduction was initially obtained, two of 25 (8%) went on to require further corrective surgery and one of 25 (4%) had a redislocation event. With the numbers available, no patient-specific factors at the time of closed reduction were predictive of future AVN, including the patient's age/weight, the presence of an ossific nucleus, history of previous bracing treatment, or the abduction angle in spica cast.

CONCLUSIONS

A pMRI-based protocol immediately after closed reduction/spica casting may decrease the risk of AVN by helping the surgeon to evaluate femoral head vascularity. Although preliminary in nature, this study could serve to guide further investigation into the potential role of pMRI for the treatment of patients who require closed reduction/spica casting for DDH.

LEVEL OF EVIDENCE

Level III, therapeutic study.

What Risk Factors and Characteristics Are Associated With Late-presenting Dislocations of the Hip in Infants?

BACKGROUND

Most infants with developmental dysplasia of the hip (DDH) are diagnosed within the first 3 months of life. However, late-presenting DDH (defined as a diagnosis after 3 months of age) does occur and often results in more complex treatment and increased long-term complications. Specific risk factors involved in late-presenting DDH are poorly understood, and clearly defining an associated set of factors will aid in screening, detection, and prevention of this condition.

QUESTIONS/PURPOSES

Using a multicenter database of patients with DDH, we sought to determine whether there were differences in (1) risk factors or (2) the nature of the dislocation (laterality and joint laxity) when comparing patients with early versus late presentation.

METHODS

A retrospective review of prospectively collected data from a multicenter database of patients with dislocated hips was conducted from 2010 to 2014. Baseline demographics for fetal presentation (cephalic/breech), birth presentation (vaginal/cesarean), birth weight, maternal age, maternal parity, gestational age, family history, and swaddling history of patients were compared among nine different sites for patients who were enrolled at age younger than 3 months and those enrolled between 3 and 18 months of age. A total of 392 patients were enrolled at baseline between 0 and 18 months of age with at least one dislocated hip. Of that group, 259 patients were younger than 3 months of age and 133 were 3 to 18 months of age. The proportion of patients with DDH who were enrolled and followed at the nine participating centers was 98%.

RESULTS

A univariate/multivariate analysis was performed comparing key baseline demographics between early- and late-presenting patients. After controlling for relevant confounding variables, two variables were identified as risk factors for late-presenting DDH as compared with early-presenting: cephalic presentation at birth and swaddling history. Late-presenting patients were more likely to have had a cephalic presentation than early-presenting patients (88% [117 of 133] versus 65% [169 or 259]; odds ratio [OR], 5.366; 95% confidence interval [CI], 2.44-11.78; p < 0.001). Additionally, late-presenting patients were more likely to have had a history of swaddling (40% [53 of 133] versus 25% [64 of 259]; OR, 2.053; 95% CI, 1.22-3.45; p = 0.0016). No difference was seen for sex (p = 0.63), birth presentation (p = 0.088), birth weight (p = 0.90), maternal age (p = 0.39), maternal parity (p = 0.54), gestational age (p = 0.42), or family history (p = 0.11) between the two groups. Late presenters were more likely to present with an irreducible dislocation than early presenters (56% [82 of 147 hips] versus 19% [63 of 333 hips]; OR, 5.407; 95% CI, 3.532-8.275; p < 0.001) and were less likely to have a bilateral dislocation (11% [14 of 133] versus 28% [73 of 259]; OR, 0.300; 95% CI, 0.162-0.555; p = 0.002).

CONCLUSIONS

Those presenting with DDH after 3 months of age have fewer of the traditional risk factors for DDH (such as breech birth), which may explain the reason for a missed diagnosis at a younger age. In addition, swaddling history was more common in late-presenting infants. A high index of suspicion for DDH should be maintained for all infants, not just those with traditional risk factors for DDH. Further investigation is required to determine if swaddling is a risk factor for the development of hip dislocations in older infants. More rigorous examination into traditional screening methods should also be performed to determine whether current screening is sufficient and whether late-presenting dislocations are present early and missed or whether they develop over time.

LEVEL OF EVIDENCE

Level III, retrospective study.

Prevalence of acetabular labral tears in asymptomatic children

PURPOSE

Magnetic resonance imaging (MRI) is a sensitive, non-invasive modality to diagnose acetabular labral pathology, and the normal variants of the acetabular labrum have been characterized in adults. However, the prevalence of labral pathology in the asymptomatic pediatric population is unknown.

METHODS

All pelvic MRIs performed at a large tertiary-care children's hospital were reviewed during one calendar year (2014). Only patients aged between 2 and 18 years were included, and scans were excluded for hip pain/pathology or technical inadequacy. A blinded pediatric musculoskeletal radiologist read all eligible scans for the presence or absence of a labral tear.

RESULTS

Three hundred and ninety-four pelvic MRIs were screened, and patients were excluded for hip pain/pathology (85 subjects), or technical inadequacy (190 subjects). One hundred and eight subjects (216 hips) met the inclusion criteria and were technically adequate for analysis. Labral tears were visualized in three of 216 (1.4 %) hips (two of the 110 subjects; 1.9 %).

CONCLUSIONS

There is a low rate of asymptomatic labral pathology by MRI in pediatric patients. The clinical history remains the means of differentiating real labral pathology from spurious imaging findings.

LEVEL OF EVIDENCE IV

Case series (prevalence).

Rapid Recovery Pathway After Spinal Fusion for Idiopathic Scoliosis

BACKGROUND

Posterior spinal fusion (PSF) for adolescent idiopathic scoliosis (AIS) is associated with significant pain and prolonged hospitalization. There is evidence that early mobilization and multimodal analgesia can accelerate functional recovery and reduced length of stay (LOS). Using these principles, we implemented a quality improvement initiative to enable earlier functional recovery in our AIS-PSF population.

METHODS

We designed and implemented a standardized rapid recovery pathway (RRP) with evidence-based management recommendations for children aged 10 to 21 years undergoing PSF for AIS. Our primary outcome, functional recovery, was assessed using statistical process control charts for LOS and average daily pain scores. Our process measures were medication adherence and order set utilization. The balancing measure was 30-day readmission rate.

RESULTS

We included 322 patients from January 1, 2011 to June 30, 2015 with 134 (42%) serving as historical controls, 104 (32%) representing our transition population, and 84 (26%) serving as our RRP population. Baseline average LOS was 5.7 days and decreased to 4 days after RRP implementation. Average daily pain scores remained stable with improvement on postoperative day 0 (3.8 vs 4.9 days) and 1 (3.8 vs 5 days) after RRP implementation. In the second quarter of 2015, gabapentin (91%) and ketorolac (95%) use became routine and order set utilization was 100%. Readmission rates did not increase as a result of this pathway.

CONCLUSIONS

Implementation of a standardized RRP with multimodal pain management and early mobilization strategies resulted in reduced LOS without an increase in reported pain scores or readmissions.

Labral morphologic characteristics in patients with symptomatic acetabular dysplasia

BACKGROUND

The morphologic characteristics of the labrum in patients with symptomatic acetabular dysplasia have been described to some extent in smaller retrospective series, but the need remains to further define these disease characteristics and their importance as a diagnostic feature of hip instability.

PURPOSE

To (1) characterize the morphologic characteristics of the labrum in patients with symptomatic acetabular dysplasia and (2) test the relationships between specific labral variants, severity of dysplasia, and duration of symptoms.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

Thirteen surgeons from 10 centers enrolled patients undergoing periacetabular osteotomy (PAO) for symptomatic acetabular dysplasia from 2008 to 2014. Patient demographics, presenting characteristics, preoperative radiographic data, operative data, and intraoperative findings were prospectively collected and retrospectively reviewed.

RESULTS

A total of 942 patients (972 hips) met the initial inclusion criteria, with a mean age of 25.2 years (range, 9-51 years; 84% female, 16% male). In addition to having PAO, 52.6% of hips had an anterior arthrotomy and 19.8% had a hip arthroscopy either to perform an osteochondroplasty of the femoral head-neck junction or to address labral pathologic changes. Of these 553 hips in which the labrum was visualized, labral morphologic status was graded as hypertrophic in 50%, normal in 45%, hypoplastic in 4%, and ossified in less than 1%. Decreased lateral center-edge angle and anterior center-edge angle and increased acetabular inclination were associated with labral hypertrophy, but chronicity of symptoms was not. Of the 553 hips, 64% had tears of the labrum, with the majority being degenerative-type tears.

CONCLUSION

Labral pathologic changes are common in patients with symptomatic acetabular dysplasia. Labral hypertrophy, however, is not a universal finding, particularly in hips with mild dysplasia, and therefore should not be considered a reliable diagnostic criterion for instability.

The presentation of Legg-Calvé-Perthes disease in females

PURPOSE

Legg-Calvé-Perthes disease (LCPD) is uncommon in girls. The presentation of LCPD in female patients has been reported as later in onset and associated with certain high-impact activities. Our aim is to characterize the presentation of female LCPD at a large center, with particular attention to the clinical and radiographic features of late-onset disease (>ten years of age). We perceived an increasing burden of late-onset disease with adult-like radiographic features.

METHODS

All patients presenting to a single large urban children's hospital from 1990-2014 with a diagnosis of LCPD were reviewed. Demographic, clinical, and radiographic data for all female patients were examined and compared to historical norms.

RESULTS

Four-hundred and fifty-one patients presented with LCPD in the study period, of which 82 (18.2 %) were female. The average age at presentation was 6.58 years in girls, which is similar to the classically reported mean age. Fourteen patients participated in high-impact repetitive activities or those with deep flexion and abduction, although few were late presenters. There were four female patients who presented for initial diagnosis >ten years of age.

CONCLUSIONS

There was a paucity of late-onset LCPD in girls in the study population, and the females with LCPD had a very similar age and character to their presentation as did males. Although their presentation is infrequent, three of four older females with LCPD were engaged in high-level physical activity, and their disease may be attributed to high-impact, repetitive athletics.

LEVEL OF EVIDENCE

Case series, Level IV.

Safe transcranial electric stimulation motor evoked potential monitoring during posterior spinal fusion in two patients with cochlear implants

Transcranial electric stimulation (TES) motor evoked potentials (MEPs) have become a regular part of intraoperative neurophysiologic monitoring (IONM) for posterior spinal fusion (PSF) surgery. Almost all of the relative contraindications to TES have come and gone. One exception is in the case of patients with a cochlear implant (CI). Herein we illustrate two cases of pediatric patients with CIs who underwent PSF using TES MEPs as part of IONM. In both instances the patients displayed no untoward effects from TES, and post-operatively both CIs were intact and functioning as they were prior to surgery.

Ilfeld abduction orthosis is an effective second-line treatment after failure of Pavlik harness for infants with developmental dysplasia of the hip

BACKGROUND

Closed reduction and spica casting is the most commonly recommended choice for infants with developmental dysplasia of the hip (DDH) for whom Pavlik harness treatment has failed, but it requires general anesthesia in addition to the challenges of spica cast care. The purposes of this study were to evaluate the effectiveness of Ilfeld bracing for infants for whom Pavlik harness treatment is unsuccessful and to compare these results with those for a similar cohort of patients directly undergoing closed reduction and spica casting.

METHODS

We reviewed the cases of a consecutive series of children with DDH who had failure of Pavlik harness treatment and were subsequently managed with Ilfeld bracing (the BR cohort) and compared this cohort with a similar historical group of infants who had failure of Pavlik harness treatment but had standard closed reduction and spica casting (the CR cohort). The cohorts were compared with respect to clinical and ultrasonographic data at the time of Pavlik discontinuation. At one year, the hip stability and acetabular index were assessed; the presence of osteonecrosis was graded according to the criteria described by Salter et al.

RESULTS

Twenty-eight hips (nineteen infants) made up the BR cohort and twenty-two hips (sixteen infants) made up the CR cohort. Ultrasonographic indices (including the alpha angle and the percentage of femoral head coverage) were comparable between the two cohorts (p=0.66 and 0.19, respectively). Following treatment, a stable reduction was achieved in twenty-three (82%) of twenty-eight hips in the BR cohort compared with twenty (91%) of twenty-two hips in the CR cohort. At one year, acetabular indices were similar between both cohorts (mean and standard deviation, 27°±6° for the BR cohort versus 27°±5° for the CR cohort; p=0.62); however, osteonecrosis developed in three hips in the CR cohort compared with none in the BR cohort.

CONCLUSIONS

In our series of infants with DDH for whom Pavlik harness treatment had failed, Ilfeld bracing had success rates comparable with those for closed reduction and spica cast treatment. With the added advantages of avoiding general anesthesia and spica casting as well as a potentially lower rate of osteonecrosis, rigid abduction bracing should be considered as the next step for infants who have had failed Pavlik harness treatment prior to proceeding with closed reduction and spica casting.