The Longitudinal Effects of Posterior Spinal Fusion with Derotation on Axial Deformity in Adolescent Idiopathic Scoliosis

STUDY DESIGN

Retrospective case series.

OBJECTIVE

To characterize the change in angle of trunk rotation (ATR), axial vertebral rotation (AVR), and body surface rotation (BSR) in patients with adolescent idiopathic scoliosis (AIS) undergoing posterior spinal fusion (PSF) with en-bloc derotation across multiple postoperative visits.

SUMMARY OF BACKGROUND DATA

Previous research has documented ATR, AVR, and BSR correction for AIS patients after surgery. However, there is a lack of evidence on the sustainability of this correction over time.

METHODS

This was a retrospective study from a single-center prospective surface topographic registry of patients with AIS, age 11-20 at time of surgery, who underwent PSF with en-bloc derotation. Patients with previous spine surgery were excluded. ATR was measured with a scoliometer, AVR through EOS radiographic imaging, and BSR via surface topographic scanning, Data collection occurred at: preoperative, six-week, three-month, six-month, one-year, and two-year postoperative visits. BSR and AVR were tracked at the preoperative apical vertebral level, and the level with maximum deformity, at each respective timepoint. Generalized estimating equations models were used for statistical analysis. Covariates included age, sex, and body mass index.

RESULTS

49 patients (73.4% female, mean age 14.6±2.2 years, mean preoperative coronal curve angle 57.9°±8.5, and 67% major thoracic) were evaluated. ATR correction was significantly improved at all postoperative timepoints and there was no significant loss of correction. AVR Max and AVR Apex were significantly improved at all timepoints but there was a significant loss of correction for AVR Apex between the six-week and one-year visit (P=0.032). BSR Max achieved significant improvement at the three-month visit. BSR Apex was significantly improved at the three-month and one-year visit.

CONCLUSION

ATR and AVR demonstrated significant axial plane correction at two-years postoperative in patients undergoing PSF for AIS. BSR did not maintain significant improvement by the two-year visit.

Utilizing robotic-assisted navigation for pelvic instrumentation in pediatric patients with neuromuscular scoliosis: a technical note and case series

Pelvic fixation is commonly used in correcting pelvic obliquity in pediatric patients with neuromuscular scoliosis and in preserving stability in adult patients with lumbosacral spondylolisthesis or instances of traumatic or osteoporotic fracture. S2-alar-iliac screws are commonly used in this role and have been proposed to reduce implant prominence when compared to traditional pelvic fusion utilizing iliac screws. The aim of this technical note is to describe a technique for robotically navigated placement of S2-alar-iliac screws in pediatric patients with neuromuscular scoliosis, which (a) minimizes the significant exposure needed to identify a bony start point, (b) aids in instrumenting the irregular anatomy often found in patients with neuromuscular scoliosis, and (c) allows for greater precision than traditional open or fluoroscopic techniques. We present five cases that underwent posterior spinal fusion to the pelvis with this technique that demonstrate the safety and efficacy of this procedure.

Novel Surface Topographic Assessment of Lung Volume and Pulmonary Function Tests in Idiopathic Scoliosis: A Preliminary Study

OBJECTIVE

Severe spinal deformity results in restrictive pulmonary disease from thoracic distortions and lung-volume limitations. Though spirometry and body plethysmography are widely accepted tests for pulmonary function tests (PFTs), they are time-consuming and require patient compliance. This study investigates whether surface topographic [surface topography (ST)] measurements of body volume difference (BVD) and torso volume difference between maximum inhale and exhale correlate to values determined on PFTs.

METHODS

This study included patients with idiopathic scoliosis and thoracic/thoracolumbar curves ≥40 degrees. Patients received ST scans, clinical examinations, and EOS biplanar radiographs on the same day. PFTs were performed within 3 months of ST/radiographic analysis. Univariate linear regression analysis was used to examine relationships between BVD, PFT values, and mean curves.

RESULTS

Sixteen patients (14.6 ± 2.2 y, 69% females) with idiopathic scoliosis and mean thoracic/thoracolumbar curves of 62 degrees ± 15˚ degrees (45 degrees to 93 degrees) were assessed. BVD displayed statistically high-positive positive correlations with forced vital capacity (R= 0.863, P< 0.0001), forced expiratory volume in 1 second (R= 0.870, P< 0.001), vital capacity (R= 0.802, P< 0.0001), and TLC (R= 0.831, P< 0.0001. Torso volume difference showed similarly high positive correlations to forced vital capacity, forced expiratory volume in 1 second, vital capacity, and TLC, but not residual volume. No correlations emerged between the mean thoracic/thoracolumbar curve and BVD or PFT values.

CONCLUSION

This study strongly endorses further investigation into ST scanning as an alternative to traditional PFTs for assessing pulmonary volumes. The noncontact and noninvasive nature of ST scanning presents a valuable alternative method for analyzing thoracic volume, particularly beneficial for patients unable to cooperate with standard PFTs.

LEVEL OF EVIDENCE

Level II-prognostic.

Analysis of 5,070 consecutive pedicle screws placed utilizing robotically assisted surgical navigation in 334 patients by experienced pediatric spine deformity surgeons: surgical safety and early perioperative complications in pediatric posterior spinal fusion

PURPOSE

This study evaluates the intraoperative and short-term complications associated with robotically assisted pedicle screw placement in pediatric posterior spinal fusion (PSF) from three surgeons at two different institutions.

METHODS

We retrospectively reviewed 334 pediatric patients who underwent PSF with robotic-assisted navigation at 2 institutions over 3 years (2020-2022). Five thousand seventy robotically placed screws were evaluated. Data collection focused on intraoperative and early postoperative complications with minimum 30-day follow-up. Patients undergoing revision procedures were excluded.

RESULTS

Intraoperative complications included 1 durotomy, 6 patients with neuromonitoring alerts not related to screw placement, and 62 screws (1.2%) with documented pedicle breaches, all of which were revised at time of surgery. By quartile, pedicle breaches statistically declined from first quartile to fourth quartile (1.8% vs. 0.56%, p < 0.05). No breach was associated with neuromonitoring changes or neurological sequelae. No spinal cord or vascular injuries occurred. Seventeen postoperative complications occurred in eleven (3.3%) of patients. There were five (1.5%) patients with unplanned return to the operating room.

CONCLUSION

Robotically assisted pedicle screw placement was safely and reliably performed on pediatric spinal deformity by three surgeons across two centers, demonstrating an acceptable safety profile and low incidence of unplanned return to the operating room.

Risk Factors for Blood Transfusions in Elective Single-Level Anterior Lumbar Interbody Fusion for Degenerative Conditions

Background

ALIF (anterior lumbar interbody fusion) and other spinal fusion surgeries are among the most common orthopaedic procedures requiring blood transfusions. However, blood transfusions have been associated with various complications, including adverse reactions and infections. The present study aims to identify independent risk factors for blood transfusions in patients undergoing single-level ALIF specifically to better identify high risk patients and optimize perioperative management.

Methods

All patients who had undergone single-level ALIF patients for the treatment of degenerative spinal conditions, excluding traumatic, pathologic, and infectious etiologies, were identified by querying a multi-institutional surgical registry from 2005 to 2018. Multi-level fusions, PLIF/TLIF, and posterior procedures were also excluded. Mann-Whitney-U-Tests were used to analyze continuous variables, while Fisher's-Exact-Tests/Bonferroni-Corrected-Tests were used for categorical variables. Multivariate logistic regression analysis with alternating backward stepwise elimination and forward entry was implemented to identify significant predictors for blood transfusions within 72 hours after incision. The predicted probabilities were used in post-regression diagnostics to generate a Receiver Operating Characteristic (ROC) curve to assess model performance.

Results

4,792 single-level ALIF patients met inclusion criteria - 183 (3.82%) had received blood transfusions within 72 hours after incision and 4,609 (96.18%) had not. Age ≥60 years (OR 1.954, p<0.001), preoperative transfusions (OR 33.758, p=0.023), extended operative times (≥197.0 minutes; 75th percentile) (OR 4.645, p<0.001), ASA≥3 (OR 1.395, p<0.001) and preoperative hematocrit levels (Hct) 30.00-37.99 (OR 1.562, p=0.016) and Hct <30.00 (OR 6.334, p<0.001) were shown to be significant independent risk factors for perioperative blood transfusions. The area under the ROC curve (AUROC; C-statistic) was 0.759 (p<0.001), indicating relatively strong discriminatory ability/predictability of the final model.

Conclusion

Several independent risk factors including age ≥60 years, preoperative blood transfusions and extended operative times increased risk for blood transfusion following single-level ALIF. The present study aims to help surgeons identify high-risk patients to better communicate postoperative expectations and optimize patients to reduce the risk of transfusions and secondary complications. Level of Evidence: III.

Exploring Correlations Between Pain and Deformity in Idiopathic Scoliosis With Validated Self-reported Pain Scores, Radiographic Measurements, and Trunk Surface Topographic Measurements

BACKGROUND

Up to 75% of patients with idiopathic scoliosis (IS) report back pain, but the exact contributors are unclear. This study seeks to assess how pain correlates with demographics, radiographic and surface topographic (ST) measurements, and patient-reported outcome measures (PROMs) in patients with IS.

METHODS

Patient-Reported Outcome Measurement Information System (PROMIS) Pain Interference (PI) and Scoliosis Research Society revised (SRS-22r) pain domain from an IRB approved prospectively collected registry containing patients 11 to 21 years old with IS were correlated (Spearman coefficients) with measurements from whole-body EOS radiography and ST scanning, PROMIS 1.0 PROMs, Trunk Appearance Perception Scale (TAPS), and SRS-22r domains. SRS-22r and PROMIS-PI were also compared between different sex, scoliosis severities, and primary curve locations with Mann-Whitney U or Kruskal-Wallis tests, and if significant differences were found, included with the 5 highest univariate correlated variables into stepwise multivariate linear regression models ( P <0.05 to enter, P >0.1 to remove) predicting SRS-22r pain and PROMIS-PI.

RESULTS

One hundred and forty-nine patients (14.5 ± 2.0 y, body mass index 20.6 ± 4.1 kg/m 2 , 96 (64%) female, mean major coronal curve 40 ± 19 deg, range: 10 deg, 83 deg) reported mean PROMIS-PI of 42.2 ± 10.0 and SRS-22r pain of 4.4 ± 0.6. SRS-22r self-image was the most correlated variable with both SRS-22r pain (rho=0.519) and PROMIS-PI (rho=-0.594). Five variables, none of which were ST or radiographic measures, strongly predicted SRS pain domain (R=0.711, R2=0.505, N=138). Two variables (SRS-22r self-image and SRS-22r function) were utilized by a model correlated with PROMIS-PI (R=0.687, R2=0.463, N=124).

CONCLUSIONS

SRS-22r function and self-image domains were more strongly correlated with SRS-22r pain and PROMIS-PI than any radiographic or ST measurements.

LEVEL OF EVIDENCE

Level II-retrospective study.

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.

The relationship between physical activity, structural deformity, and spinal mobility in adolescent idiopathic scoliosis patients

PURPOSE

Adolescent idiopathic scoliosis (AIS) patients experience structural spinal deformity, but the impact of AIS on physical activity is not widely studied. Reports of physical activity levels between children with AIS and their peers are mixed. This study sought to characterize the relationship between spinal deformity, spinal range of motion, and self-reported physical activity in AIS patients.

METHODS

Patients aged 11-21 completed self-reported measures of physical activity using the HSS Pedi-FABS and PROMIS Physical Activity questionnaires. Radiographic measures were obtained from standing biplanar radiographic imaging. Surface topographic (ST) imaging data was obtained using a whole-body ST scanning system. Hierarchical linear regression models analyzed the relationship between physical activity, ST, and radiographic deformity while controlling for age and BMI.

RESULTS

149 patients with AIS (mean age 14.5 ± 2.0 years, mean Cobb angle 39.7° ± 18.9°) were included. In the hierarchical regression predicting physical activity from Cobb angle, no factors were significant predictors of physical activity. When predicting physical activity from ST ROM measurements, age and BMI served as covariates. No covariates or ST ROM measurements were significant predictors of physical activity levels for either activity measure.

CONCLUSIONS

Physical activity levels of patients with AIS were not predicted by levels of radiographic deformity or surface topographic range of motion. Although patients may experience severe structural deformity and range of motion limitations, these factors do not appear to be associated with decreased physical activity level utilizing validated patient activity questionnaires.

LEVEL OF EVIDENCE

Level II.

Changes in height, weight, and body mass index after posterior spinal fusion in juvenile and adolescent idiopathic scoliosis

Purpose

Posterior spinal fusion for idiopathic scoliosis is known to increase spinal height, but the impacts on weight and resulting body mass index are unknown. This study assesses body mass index, weight, and height percentile changes over time after posterior spinal fusion for idiopathic scoliosis.

Methods

Body mass index, weight, and height age- and sex-adjusted percentiles for patients with idiopathic scoliosis undergoing posterior spinal fusion between January 2016 and August 2022 were calculated based on growth charts from the Centers for Disease Control for Disease Control and compared to preoperative values at 2 weeks, 3 months, 6 months, 1 year, and 2 years. The data were analyzed for normality with a Shapiro-Wilk test, and percentiles were compared with the Wilcoxon signed-rank tests.

Results

On average, 12.1 ± 2.3 levels were fused in 269 patients 14.4 ± 1.9 years, and percentiles for body mass index, weight, and height preoperatively were 55.5 ± 29.4%, 57.5 ± 28.9%, and 54.6 ± 30.4%, respectively. Body mass index and weight percentiles decreased at 2 weeks (-10.7%, p < 0.001; -4.6%, p < 0.001, respectively) and 3 months (-6.9%, p < 0.001; -3.2%, p < 0.001, respectively) postoperatively. Postoperative weight loss at 2 weeks averaged 2.25 ± 3.09% of body weight (0.98 ± 4.5 kg), normalizing by 3 months. Body mass index percentile normalized at 1 year, but height percentile was increased at 2 weeks (2.42 ± 1.72 cm, p < 0.001) and through 2 years.

Conclusion

Despite initial height increase due to deformity correction, acute postoperative weight and body mass index percentile decreases postoperatively normalize by 1-year body mass index percentile. Physicians may benefit from utilizing this information when discussing the postoperative course of posterior spinal fusion with idiopathic scoliosis.

Level of evidence

4, Retrospective Case Series.

3D surface topographic measurements for idiopathic scoliosis are highly correlative to patient self-image questionnaires

PURPOSE

Adolescent idiopathic scoliosis (AIS) is a deformity of the spine that results in external asymmetry of the torso in the shoulder, waist, and rib hump. Several patient reported outcome measures (PROMS) including the Trunk Appearance Perception Scale (TAPS) and SRS-22r self-image domain are used to measure the patient's self-perception. The purpose of this study is to investigate the relationship between objective surface topographic measurements of the torso to subjective patient self-perception.

METHODS

131 AIS subjects and 37 controls participated in this study. All subjects completed TAPS and SRS-22r PROMS followed by whole body 3d surface topographic scanning. An automated analysis pipeline was used to compute 57 measurements. Multivariate linear models were developed to predict TAPS and SRS-22r self-image using each unique combination of 3 parameters and leave one out validation where the best combinations were selected.

RESULTS

Back surface rotation, waist crease vertical asymmetry and rib prominence volume were most predictive of TAPS. The final predicted TAPS values from leave one out cross validation was correlated to ground truth TAPS scores with an R value of 0.65. Back surface rotation, silhouette centroid deviation, and shoulder normal asymmetry were most predictive of SRS-22r self-image with a correlation of R = 0.48.

CONCLUSION

Surface topographic measurements of the torso are correlated to TAPS and SRS-22r self-image scores in AIS patients and controls, with TAPS exhibiting a stronger relationship, better reflecting the patient's external asymmetries.

Risk Factors for Surgical Site Infections After Single-Level Anterior Lumbar Interbody Fusion

Abstract Background: Anterior lumbar interbody fusion (ALIF) has become an increasingly popular and effective treatment modality for various conditions of the lumbar spine. However, complications after this procedure can be costly. Surgical site infections (SSIs) are one of these types of complications. The present study identifies independent risk factors for SSI after single-level ALIF to identify high-risk patients better. Patients and Methods: The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database was queried to identify single-level ALIF patients from 2005 to 2016. Multilevel fusions and non-anterior approach procedures were excluded. Mann-Pearson χ² tests analyzed categorical variables, whereas one-way analysis of variance (ANOVA) and independent t-tests analyzed differences in mean values of continuous variables. Risk factors for SSI were identified via a multivariable logistic regression model. A receiver operating characteristic (ROC) curve was generated utilizing the predicted probabilities. Results: A total of 10,017 patients met inclusion criteria; 80 (0.80%) had developed SSI and 9,937 (99.20%) had not. On multivariable logistic regression models, class 3 obesity (p = 0.014), dialysis (p = 0.025), long-term steroid use (p = 0.010), and wound classification 4 (dirty/infected) (p = 0.002) all independently increased the risk for SSI in single-level ALIF. The area under the receiver operating characteristic curve (AUROC; C-statistic) was 0.728 (p < 0.001), indicating relatively strong reliability of the final model. Conclusions: Several independent risk factors including obesity, dialysis, long-term steroid use, and dirty wound classification all increased risk for SSI after single-level ALIF. By identifying these high-risk patients, surgeons and patients can have more informed pre-operative discussions. In addition, identifying and optimizing these patients prior to operative intervention may help to minimize infection risk.

Hip hemiarthroplasty for the treatment of femoral neck fractures in dialysis patients

OBJECTIVES

This study sought to delineate the postoperative outcomes in dialysis patients undergoing hip hemiarthroplasty (HHA) for the treatment of femoral neck fractures (FNF) in order to better optimise pre- and postoperative management and minimise short-term morbidity and mortality rates.

METHODS

16,955 patients who had undergone HHA for femoral neck fractures from 2005 to 2018 were isolated from a multi-institutional surgical registry, of which 343 (2.0%) were on dialysis and 16,612 (98.0%) were not. The cohorts were identified/analysed for differences in their comorbidities, demographic factors, and 30-day postoperative complications using Fischer's exact tests and Mann-Whitney U-tests. Coarsened exact matching (CEM) was implemented in order to control for baseline difference in demographics and comorbidities. Multivariate logistic regression analyses were used to assess the impact of dialysis as an independent risk factor for various complications, including reoperations, readmissions, and mortality.

RESULTS

Upon CEM-matching (L1-statistic <0.001), weighted multivariate logistic regression analyses demonstrated dialysis to be an independent risk factor for minor complications (OR 3.051, p < 0.001), pneumonia (OR 3.943, p < 0.001), urinary tract infections (UTIs) (OR 2.684, p < 0.001), major complications (OR 1.892, p < 0.001), unplanned intubation (OR 2.555, p = 0.047), cardiac arrest (OR 11.897, p < 0.001), deep vein thrombosis (DVT), (OR 2.610, p = 0.049), and mortality (OR 2.960, p < 0.001).

CONCLUSIONS

Dialysis independently increased the risk for unplanned intubation, cardiac arrest, blood transfusions, pneumonia, DVT, and mortality. In communicating postoperative expectations, surgeons should aim to clarify the patients' preferences and potential resuscitation designations prior to surgical intervention due to the increased risk of serious complications. A lower threshold of suspicion for DVT in this population is reasonable. Identifying high-risk patient populations that may experience increased rates of complications, with the ensuing financial expenditures, due to medical complexity rather than subpar management may help providers avoid penalties in caring for these patients.

Advances in robotics and pediatric spine surgery

PURPOSE OF REVIEW

Robotic-assisted surgical navigation for placement of pedicle screws is one of the most recent technological advancements in spine surgery. Excellent accuracy and reliability results have been documented in the adult population, but adoption of robotic surgical navigation is uncommon in pediatric spinal deformity surgery. Pediatric spinal anatomy and the specific pediatric pathologies present unique challenges to adoption of robotic assisted spinal deformity workflows. The purpose of this article is to review the safety, accuracy and learning curve data for pediatric robotic-assisted surgical navigation as well as to identify "best use" cases and technical tips.

RECENT FINDINGS

Robotic navigation has been demonstrated as a safe, accurate and reliable method to place pedicle screws in pediatric patients with a moderate learning curve. There are no prospective studies comparing robotically assisted pedicle screw placement with other techniques for screw placement, however several recent studies in the pediatric literature have demonstrated high accuracy and safety as well as high reliability. In addition to placement of pediatric pedicle screws in the thoracic and lumbar spine, successful and safe placement of screws in the pelvis and sacrum have also been reported with reported advantages over other techniques in the setting of high-grade spondylolisthesis as well as pelvic fixation utilizing S2-alar iliac (S2AI) screws.

SUMMARY

Early studies have demonstrated that robotically assisted surgical navigation for pedicle screws and pelvic fixation for S2AI screws is safe, accurate, and reliable in the pediatric population with a moderate learning curve.

Case report: vertebral body tethering for idiopathic scoliosis in a patient with bilateral phocomelia

PURPOSE

The purpose of this study is to present a case report of a patient with bilateral upper extremity phocomelia with progressive scoliosis, who underwent vertebral body tethering (VBT).

METHODS

This is a case report on the use of VBT in a patient with scoliosis and bilateral congenital phocomelia, with 5 year follow-up.

RESULTS

A male patient with bilateral phocomelia had early onset scoliosis that progressed to 45° at age 10. Surgical options were discussed, including traditional VBT, posterior spinal fusion, growing rods, magnetically controlled growing rods, and vertical expandible prosthetic titanium ribs. These options would limit the flexibility of the spine. Given these pitfalls, VBT was chosen, as it would address the scoliosis while maintaining trunk flexibility. Preoperatively, he had 45° right main thoracic curve, bending to 22°; he was Risser 0 with open triradiate cartilage. He underwent T6-T11 thoracoscopic VBT, with postoperative correction to 37°. Postoperatively, the patient was able to continue to use his lower extremities for writing, feeding, and personal grooming. He had no postoperative complications. At 3 years, his curve was 21°, and at 5 years was 19°.

CONCLUSION

This case describes a novel technique for treating scoliosis in patients with bilateral phocomelia. Other forms of scoliosis surgical treatment limit motion of the spine. Due to this, we present VBT as an option for this unique set of patients for correcting scoliosis, while also preserving trunk flexibility for its role in feeding and self-care.

Lengthening Behavior of Magnetically Controlled Growing Rods in Early-Onset Scoliosis: A Multicenter Study

BACKGROUND

The "law of diminishing returns" is described for traditional growing rods. Magnetically controlled growing rods (MCGRs) have become a preferred implant for the surgical treatment of early-onset scoliosis (EOS). We examined a large cohort of patients with EOS to determine whether the law of diminishing returns applies to MCGRs.

METHODS

A prospectively collected, multicenter registry was queried for patients with EOS treated with MCGRs. Patients with only spine-based implants and a minimum of 2 years of follow-up were included; patients with congenital scoliosis, single rods, <3 lengthenings, or >25% missing data were excluded. Patients were analyzed in 3 cohorts: primary MCGR (pMCGR) had first-time MCGR implants, secondary MCGR (sMCGR) were converted from an MCGR to a new MCGR, and conversion MCGR (cMCGR) were converted from a non-MCGR implant to MCGR.

RESULTS

A total of 189 patients in the pMCGR group, 44 in the cMCGR group, and 41 in the sMCGR group were analyzed. From post-MCGR placement to the most recent follow-up or pre-definitive procedure, there were no differences in the changes in major Cobb angle, T1-S1 height, or T1-T12 height over time between the pMCGR and cMCGR groups. There was a decrease in length achieved at subsequent lengthenings in all cohorts (p < 0.01), and the sMCGR group had a significantly poorer ability to lengthen at each subsequent lengthening versus the pMCGR and cMCGR groups (p < 0.02). The 1-year survival rate was 90.5% for pMCGR, 84.1% for sMCGR, and 76.4% for cMCGR; 2-year survival was 61.5%, 54.4%, and 41.4%, respectively; and 3-year survival was 37.6%, 36.7%, and 26.9%, respectively. Excluding MCGRs still expanding, 27.6% of pMCGRs, 8.8% of sMCGRs, and 17.1% of cMCGRs reached the maximum excursion. Overall, 21.7% reached the maximum excursion. Within the pMCGR cohort, idiopathic and neuromuscular etiologies had a decline in lengthening achieved over time (p < 0.001), while syndromic EOS demonstrated a preserved ability to lengthen over time (p = 0.51). When the etiological groups were compared with each other, the neuromuscular group had the least ability to lengthen over time (p = 0.001 versus syndromic, p = 0.02 versus idiopathic).

CONCLUSIONS

The MCGR experiences the law of diminishing returns in patients with EOS. We found that only 21.7% of rods expanded to within 80% of the maximum excursion.

LEVEL OF EVIDENCE

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

Benchmarking surgical indications for adolescent idiopathic scoliosis across time, region, and patient population: a study of 4229 cases

PURPOSE

There is no identified consensus for the curve magnitude at which an adolescent idiopathic scoliosis (AIS) patient is indicated for posterior spinal fusion (PSF). We aimed to identify a benchmark for curve magnitude at which fusion is indicated; we also aimed to evaluate which patients were being fused under 50°.

METHODS

A prospective multicenter AIS database was queried to identify patients who underwent PSF for AIS. Clinical outcome and demographic information was collected along with anatomic area of the primary curve. Benchmarking was assessed by median and IQR. Patients were stratified by fusion prior to 50° or at 50° or more, and statistical analysis was performed to assess risk factors for fusion < 50°.

RESULTS

4229 patients were included in the analysis. The median indication for PSF in the thoracic curve cohort was 55°, and in the lumbar curve cohort was 51°. Site-specific evaluation showed that two sites were more likely to fuse < 50° compared to all other sites (p < 0.05). Over time, the percentage of patients being fused < 50° has declined (p < 0.05). On univariate and multivariate analysis, lumbar curve location, increasing Risser score and female sex were all risk factors for fusion < 50° (p < 0.05). Low SRS-24 scores did not correlate to fusion below 50°.

CONCLUSION

There exist location-specific indications for posterior spinal fusion that vary throughout the country. Additionally, increasing maturity, female sex, and lumbar curve location are independent risk factors for fusion under 50°.

Risk Factors for Blood Transfusions in Primary Anatomic and Reverse Total Shoulder Arthroplasty for Osteoarthritis

BACKGROUND

The purpose of this study was to determine risk factors for blood transfusion in primary anatomic and reverse total shoulder arthroplasty (TSA) performed for osteoarthritis.

METHODS

Patients who underwent anatomic or reverse TSA for a diagnosis of primary osteoarthritis were identified in a national surgical database from 2005 to 2018 by utilizing both CPT and ICD-9/ICD-10 codes. Univariate analysis was performed on the two transfused versus non-transfused cohorts to compare for differences in comorbidities and demographics. Independent risk factors for perioperative blood transfusions were identified via multivariate regression models.

RESULTS

305 transfused and 18,124 nontransfused patients were identified. Female sex (p<0.001), age >85 years (p=0.001), insulin-dependent diabetes mellitus (p=0.001), dialysis dependence (p=0.001), acute renal failure (p=0.012), hematologic disorders (p=0.010), disseminated cancer (p<0.001), ASA ≥ 3 (p<0.001), and functional dependence (p=0.001) were shown to be independent risk factors for blood transfusions on multivariate logistic regression analysis.

CONCLUSION

Several independent risk factors for blood transfusion following anatomic/reverse TSA for osteoarthritis were identified. Awareness of these risk factors can help surgeons and perioperative care teams to both identify and optimize high-risk patients to decrease both transfusion requirements and its associated complications in this patient population. Level of Evidence: III.

Absence of a "July Effect" on Hospital Length of Stay After Primary Total Hip or Knee Arthroplasty

There is a commonly held belief in a "July effect" resulting in suboptimal outcomes as residents begin or advance in their training each summer. Previous studies have shown an absence of a July effect on clinical outcomes after total hip arthroplasty (THA) or total knee arthroplasty (TKA). However, it remains unknown whether there is a July effect on hospital length of stay (LOS) after primary THA/TKA. The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database was queried from 2006 to 2012 for cases of primary THA/TKA, excluding emergency cases or cases where the ATTEND variable indicating resident participation was coded as missing or unknown. The primary outcome was prolonged LOS, defined as greater than 4 days postoperative. Secondary outcomes, including mortality, unplanned return to the operating room, and adverse clinical events, were also recorded. Univariate and multivariate analyses, including correction for comorbidities, evaluated associations between resident involvement in a case and any outcomes, and whether this association was different in quarter 3 (July through September) vs the remainder of the year. A total of 34,818 cases were included. Residents were involved in 9669 (28%). Length of stay greater than 4 days occurred in 12% of resident cases overall vs 11% of non-resident cases. Quarter 3 also had significantly more cases with prolonged LOS (12%) vs quarters 1 and 2 and quarter 4 (all 11%). On multivariate analysis, the resident effect on LOS greater than 4 days remained significant during the entire year; however, resident involvement in quarter 3 was not associated with prolonged LOS. These results do not support the presence of a July effect on LOS after primary THA/TKA. [Orthopedics. 2021;44(4):e503-e508.].

Bilateral acetabular fractures treated with delayed total hip arthroplasty

Acetabular fractures after seizures are uncommon, and fewer than 30 cases are described in the literature. We present a patient with bilateral acetabular fractures after a seizure, with bilateral quadrilateral plate destruction and protrusio deformity. The patient underwent delayed staggered bilateral total hip arthroplasty 3 months after initial injury, with use of the femoral head as autograft for the protrusio deformities.

The impact of chronic kidney disease on postoperative complications in patients undergoing revision total knee arthroplasty: A propensity matched analysis

OBJECTIVES

Though the role of chronic kidney disease (CKD) has been studied previously in primary arthroplasty procedures of the hips and knees, there is a paucity of literature analyzing CKD's impact on surgical outcomes in revision total knee arthroplasty (rTKA) patients. As the number of patients with CKD requiring revision surgery increases, more vigilant pre-operative and post-operative measures can be taken to ensure successful outcomes. This retrospective study sought to 1) determine differences in demographics and preoperative comorbidities of patients with normal or mild CKD and those with moderate/severe CKD and 2) establish moderate/severe CKD as an independent risk factor for complications in the 30-day postoperative period in patients undergoing rTKA.

METHODS

The ACS-NSQIP database was queried for patients who had undergone rTKA from 2005 to 2016. Patient were assigned to one of five CKD severity classes after eGFR calculation and were further stratified into two cohorts: stages 1/2 vs. stages 3/4/5. After propensity matching to generate a matched normal/mild CKD cohort of rTKA patients, univariate and multivariate analyses were used to assess differences and the impact of severe CKD on the risk for complications.

RESULTS

There were significant differences in several demographic features, comorbidities, and complications between the two cohorts upon univariate analyses. Upon multivariate analyses, CKD of moderate/severe/failure status was found to be a significant independent risk factor for acute renal failure (OR 18.097, 95% CI 4.970-65.902, p < 0.001), blood transfusions (OR 1.697, 95% CI 1.500-1.919, p < 0.001), return to the operating room (OR 1.257, 95% CI 1.009-1.566, p = 0.041), extended length of stay (OR 1.707, 95% CI 1.292-2.255, p < 0.001), and mortality (OR 2.165, 95% CI 1.116-4.200, p = 0.022) in the 30-day postoperative period.

CONCLUSION

This current study found moderate/severe CKD to be an independent risk factor for several complications and should guide healthcare professionals for better patient-optimization. Orthopaedic surgeons should factor in CKD severity in the management of patients undergoing rTKA to effectively mitigate the effects of adverse events.

Hemiarthroplasty versus total hip arthroplasty for femoral neck fractures in patients with chronic obstructive pulmonary disease

PURPOSE

This study sought to delineate whether total hip arthroplasty (THA) or hip hemiarthroplasty (HHA) had more complication rates following the treatment of femoral neck fractures (FNF) in chronic obstructive pulmonary disease (COPD) patients.

MATERIALS AND METHODS

The ACS-NSQIP database was queried for all patients with a history of COPD who had undergone THA and HHA with FNFs, isolated by CPT codes and ICD-9/ICD-10 codes. Propensity score matching without replacement in a 1:1 manner was done to control for patient demographics/preoperative comorbidities. Multivariate logistic regression models were utilized to assess the independent effect of HHA in comparison to THA.

RESULTS

The propensity-matched (PM) HHA cohort was significantly older (76.14 years vs. 73.33 years, p = 0.001) and had significantly higher rates of pneumonia (p = 0.017), extended length of stay (LOS) (p = 0.017), and mortality (p = 0.002), but lower rates of blood transfusions (p = 0.016) and reoperation (p = 0.020). HHA was independently associated with an increased risk of pneumonia (p = 0.043), extended LOS (p = 0.050), and death (p = 0.044) but a decreased risk for blood transfusions (p = 0.008) and reoperation (p = 0.028) when compared to THA.

DISCUSSION

Patients with more comorbidities are more likely to receive HHA than THA, which may explain some of the increased complications and mortality associated with HHA for FNFs compared to THA. Patients undergoing THA were at increased risk for blood transfusion and reoperation. THA does not appear to result in increased morbidity in this population compared to HHA. While THA should be considered in these patients given improved functional outcomes, further prospective studies are needed to establish superiority.

LEVEL OF EVIDENCE

III.

Postoperative Complications Following Orthopedic Spine Surgery: Is There a Difference Between Men and Women?

Background

Patient sex is known to affect outcomes following surgery. Prior studies have not specifically examined sex-stratified outcomes following spine surgery. The objective is to determine the differences between men and women in terms of 30-day complications following spine surgery.

Methods

The National Surgical Quality Improvement Program database was queried for patients undergoing spine surgery from 2005 to 2014. Postoperative data were analyzed to determine the differences between men and women with regard to 30-day complications.

Results

A total of 41 315 patients (49.0% women, 51% men) were analyzed. Men were more likely to have diabetes (P = .004) and be active smokers (P < .001). Women were more likely to be taking steroids for chronic conditions (P < .001). Postoperatively, women were at increased risk for superficial surgical site infection, urinary tract infection, transfusions, and longer length of stay, whereas men were at increased risk of pneumonia and reintubation. On multivariate analysis, women were associated with urinary tract infections (odds ratio = 2.17) and transfusions (odds ratio = 1.63).

Conclusions

Differences in complications are evident between men and women following spine surgery. These differences should be considered during preoperative planning and when consenting patients for surgery.

Level of Evidence

4.

Excision of Os Trigonum in Dancers via an Open Posteromedial Approach

An os trigonum is a potential source of posterior ankle pain in dancers, often associated with flexor hallucis longus (FHL) pathology. Surgical excision is indicated on failure of nonoperative management. Options for surgical excision include open excision (via a posterolateral or posteromedial approach), subtalar arthroscopy, and posterior endoscopy. Os trigonum excision via an open posteromedial approach with concomitant FHL tenolysis/tenosynovectomy is a safe and effective method for the operative treatment of a symptomatic os trigonum that allows for identification and treatment of associated FHL pathology. The major steps in the procedure, which are demonstrated in this video article, are: (1) preoperative planning with appropriate imaging; (2) patient is positioned in a supine position with the operative extremity in figure-of-4 position; (3) a 3-cm, slightly curvilinear longitudinal incision is made midway between the posterior aspect of the medial malleolus and the anterior aspect of the Achilles tendon, over the palpated FHL tendon, and the flexor retinaculum is exposed and incised; the neurovascular bundle is retracted anteriorly, exposing the FHL tendon and sheath; (4) FHL tenolysis/tenosynovectomy is performed; (5) the FHL is retracted anteriorly and a capsulotomy is performed over the os trigonum and the os trigonum is excised; (6) the capsule is repaired and closure is performed; and (7) dressings and a CAM (controlled ankle motion) walking boot are applied. The patient begins physical therapy at 2 weeks postoperatively and may return to dance at 4 to 6 weeks postoperatively as tolerated. In our series of 40 cases, 95% of patients who desired to return to dance were able to return to their pre-injury level of dance. There were no major neurovascular complications.

Identifiable risk factors for thirty-day complications following arthroscopic rotator cuff repair

OBJECTIVES

Shoulder arthroscopy has increased in frequency over the past decade, with rotator cuff repair comprising the majority of cases performed. Prior studies have detailed risk factors for 30-day complications and readmission rates after arthroscopic shoulder surgery using the National Surgical Quality Improvement Program (NSQIP) database, but no study has specifically looked at arthroscopic rotator cuff repair. The purpose of the study is to evaluate the risk factors for 30-day complications following arthroscopic rotator cuff repair using the NSQIP database.

METHODS

The NSQIP database was queried for all patients undergoing arthroscopic rotator cuff repair from 2006-2015. Demographics and thirty-day outcomes for these patients were analyzed using univariate analyses and multivariate regression analysis to determine the risk factors for complications.

RESULTS

21,143 patients underwent arthroscopic rotator cuff repair, with 147 patients (0.70%) having a complication within 30-days. Univariate analysis found age >65 (p = 0.0028), male gender (p = 0.0053), elevated BMI (p = 0.0054), ASA class >2 (p < 0.0001), history of chronic obstructive pulmonary disease (p < 0.0001), hypertension (p < 0.0002), dyspnea (p < 0.0001), steroid use (p = 0.0350), and operative time >90 min (p = 0.0316) to be associated with increased risk of complications. Multivariate analysis found female sex to be protective or complication (OR 0.56, p = 0.0017), while American Society of Anesthesiology (ASA) class >2 (OR 1.51, p = 0.0335) and history of COPD (OR 2.41, p = 0.0030) and dyspnea (OR 1.89, p = 0.0359) to be risk factors for complication. The most common complication is venothromboembolic events, accounting for 36.7% of all complications.

CONCLUSION

Male sex, ASA class > 2, and history of COPD and dyspnea were independent risk factors for thirty-day complications following arthroscopic rotator cuff repair.

LEVEL OF EVIDENCE

IV.

Os Trigonum Excision in Dancers via an Open Posteromedial Approach

BACKGROUND

An os trigonum is a potential source of posterior ankle pain in dancers, often associated with flexor hallucis longus (FHL) pathology. Options for operative excision include open excision, subtalar arthroscopy, and posterior endoscopy. The purpose of this paper was to present a series of dancers who underwent excision of a symptomatic os trigonum via an open posteromedial approach.

METHODS

This study is a retrospective case series of 40 ankles in 38 dancers who underwent os trigonum excision via an open posteromedial approach with FHL tenolysis between 2000 and 2013. All patients were interviewed and charts retrospectively analyzed. Collected variables included pre- and postoperative pain level, time to return to dance, and subjective satisfaction. The average age was 19.2 years; ballet was the primary dance form in 36 (95%) of patient-cases. Eight (20%) of the patient-cases were professional dancers, and 30 (75%) were students or preprofessional dancers.

RESULTS

Average preoperative pain level was 7.7/10, which decreased to 0.6/10 postoperatively. Seventeen (42.5%) experienced concurrent preoperation-associated FHL symptomatology, all of whom experienced relief postoperatively. The average time to return to dance was 7.9 weeks, and time to pain-free dance was 17.7 weeks. Of the 37 patient-cases desiring to return to dance, 35 (94.6%) returned to their preoperative level of dance. There were no neurovascular or other major complications. Four (10%) had minor wound complications that resolved, and 38 cases (95%) considered the procedure a success.

CONCLUSION

Open posteromedial excision of an os trigonum in dancers provided satisfactory pain relief, return to dance, and complication rates compared to other approaches, and allowed for identifying and treating any associated FHL pathology.

LEVEL OF EVIDENCE

Level IV, retrospective case series.

Drawing the Curtain Back on Injured Commercial Bicyclists

OBJECTIVES

We determined the demographic characteristics, behaviors, injuries, and outcomes of commercial bicyclists who were injured while navigating New York City's (NYC's) central business district.

METHODS

Our study involved a secondary analysis of prospectively collected data from a level 1 regional trauma center in 2008 to 2014 of bicyclists struck by motor vehicles. We performed univariable and multivariable logistic regression analyses.

RESULTS

Of 819 injured bicyclists, 284 (34.7%) were working. Commercial bicyclists included 24.4% to 45.1% of injured bicyclists annually. Injured commercial bicyclists were more likely Latino (56.7%; 95% confidence interval [CI] = 50.7, 62.8 vs 22.7%; 95% CI = 19.2, 26.5). Commercial bicyclists were less likely to be distracted by electronic devices (5.0%; 95% CI = 2.7, 8.2 vs 12.7%; 95% CI = 9.9, 15.9) or to have consumed alcohol (0.7%; 95% CI = 0.9, 2.5 vs 9.5%; 95% CI = 7.2, 12.3). Commercial and noncommercial bicyclists did not differ in helmet use (38.4%; 95% CI = 32.7, 44.4 vs 30.8%; 95% CI = 26.9, 34.9). Injury severity scores were less severe in commercial bicyclists (odds ratio = 0.412; 95% CI = 0.235, 0.723).

CONCLUSIONS

Commercial bicyclists represent a unique cohort of vulnerable roadway users. In NYC, minorities, especially Latinos, should be targeted for safety education programs.