Arthroscopic Modified Lasso-Loop Stitch Technique for Chronic Lateral Ankle Instability in Skeletally Immature vs Mature Patients

BACKGROUND

In recent years, arthroscopic lateral ankle ligament repair has become increasingly popular. However, reports on the clinical outcomes of arthroscopic ankle stabilization for skeletally immature patients remain scarce. This study investigated the clinical outcomes of arthroscopic lateral ankle ligaments repair in skeletally immature patients compared to skeletally mature patients.

METHODS

Our retrospective analysis compared skeletally immature patients and skeletally mature adults who underwent arthroscopic repair of the ankle lateral ligaments with a modified lasso-loop stitch using a suture anchor. Skeletal immaturity was defined as patients whose epiphyseal line of the distal fibula remained open on plain radiography. Clinical outcomes were evaluated using the Self-Administered Foot Evaluation Questionnaire (SAFE-Q) at 2 years after surgery. The time to postoperative walking, jogging, and return to full sports activities were also evaluated.

RESULTS

Sixty-four skeletally immature patients (IM group) and 103 skeletally mature adults (M group) were included. No significant differences were observed during both walking and jogging after surgery between the groups; however, return to full athletic activities was significantly earlier in IM group (P = .05). The mean scores in all SAFE-Q subscales significantly improved in both groups after surgery (P < .001). There were also no statistically significant differences between the groups in the mean postoperative SAFE-Q scores for all subscales. All patients in the IM group returned to playing sports at their preinjury levels postoperatively.

CONCLUSION

We found that skeletally immature patients with chronic lateral ankle instability had generally similar responses to arthroscopic lateral ankle as skeletally mature adult patients at minimally 2 years' follow-up with a high rate of successful return to sport.

LEVEL OF EVIDENCE

Level III, retrospective case control study.

Anterior cruciate ligament reconstruction in skeletally immature patients is effective: A systematic review

PURPOSE

The present study evaluated the outcomes of anterior cruciate ligament (ACL) reconstruction in children with open physes. The outcomes of interest were to compare the increase in joint laxity and PROMs from baseline to the last follow-up, the rate and features of the return to sport and the rate of complications.

METHODS

This study was conducted according to the 2020 PRISMA guidelines. In October 2023, the following databases were accessed: PubMed, Web of Science, Google Scholar and Embase. All the clinical studies investigating ACL reconstruction in skeletally immature patients were accessed. Only articles which clearly stated that surgeries were conducted in children with open physis were eligible.

RESULTS

Data from 53 studies (1691 procedures) were collected. 35% (597 out of 1691 patients) were women. The mean length of the follow-up was 44.7 ± 31.3 months. The mean age of the patients was 12.7 ± 1.1 years old. All PROMs significantly improved from the baseline values to those at the last follow-up. The mean time to return to sport was 8.3 ± 1.9 months. 89% (690 out of 771 patients) returned to sports, 15% (109 out of 721 patients) reduced their level of sports activity or league, and 84% (651 out of 771 patients) returned to their previous level of sport. 9% (112 out of 1213) of patients experienced re-tear of the reconstructed ACL, and 11% (75 out of 660) of patients underwent a further ACL reoperation. No patients (0 out of 83) demonstrated increased laxity at the last follow-up, and persistent sensation of instability was reported by 5% (11 out of 235) of patients.

CONCLUSION

ACL reconstruction in skeletally immature patients is effective and safe, and is associated with fast recovery and a high rate of return to sport.

LEVEL OF EVIDENCE

Level IV.

Long-Term Results after Chiari Pelvic Osteotomy in the Skeletally Immature and the Role of the Anti-Chiari Effect

Several authors observed a loss of correction after performing Chiari pelvic osteotomy (CPO) in young patients. Hence, the aim of this study was to answer two questions: (1) Does the Chiari pelvic osteotomy affect the development of the acetabulum in skeletally immature patients in the long term? (2) Is there any evidence of the previously described "Anti-Chiari" effect after a mean follow-up of 36 years? Data from 21 patients (27 hips) undergoing CPO before the age of 16 years were clinically assessed, and the evolution of radiological parameters over time was analyzed. The mean age at CPO was 11.2 years (±3; 4.4-15.7). The 20- and 30-year survival rates of the CPO were 100% and 92.6%, respectively. Mean postoperative medialization was 54% (±18; 23-99). The average osteotomy angle was 11° (±7; 2-28). No significant changes were found for the center-edge angle (CEA) and acetabular index (AI) over time; the angle of Idelberger and Frank (ACM) almost reached normal values at follow-up (FU); for the acetabular-head index (AHI), a slight shift toward the initial situation could be detected. The morphology of the acetabulum remained unchanged over time. The "Anti-Chiari effect" seems to be primarily caused by insufficient coverage of the femoral head rather than damage to the apophysis due to surgery.

A Rare Giant Cell Tumour in the Distal Radius of a Seven-Year-Old Girl: A Case Report

A giant cell tumour (GCT) is a benign and locally aggressive tumour that is usually observable in a skeletally mature patient involving the end of long bones. The reported incidence of this tumour in a skeletally immature patient is extremely rare. However, we report one such case in the distal radius of a seven-year-old female patient. Having presented with painful swelling of the right distal forearm, she underwent clinical and radiological examination, and a diagnosis of distal radius GCT was made. The tumour was treated with curettage, fibular graft, and synthetic bone graft. This case report shows the importance of including GCT in children as a differential diagnosis. This tumour may have a good prognosis if diagnosed and treated early.

Meniscal Allograft Transplants in Skeletally Immature Patients: A Systematic Review of Indications and Outcomes

Meniscal lesions in skeletally immature patients can lead to joint degradation and knee instability. Meniscal allograft transplant (MAT) surgery is a solution to maintain knee stability. There is a lack of consensus on MAT surgery outcomes in pediatric patients. A systematic review was conducted according to the PRISMA guidelines. PubMed, Scopus and EMBASE databases were searched from 1965 to June 2022. Studies were evaluated using the Newcastle-Ottawa Scale (NOS). Three studies were selected, and 58 patients were included (mean age 15.9 years) in total. The lateral meniscus was involved in 82.8% of all MAT surgeries. Post-meniscectomy syndrome and discoid meniscus were the main indications for MAT surgery. All studies reported improved subjective clinical scores and levels of sport after the surgery. The complication rate was 27.5%. Partial meniscectomy, meniscus knot removal, chondral defect treatment and lysis of adhesions were the most frequent procedures performed during reoperation. MAT surgery can improve clinical outcomes in pediatric patients with strictly selected indications. MAT surgery is safe when there are no limb asymmetries or malalignments, but it remains a challenging procedure with a high complication rate. Long-term follow-up is needed for definitive statements on the use of MAT in skeletally immature patients.

Radiographic Changes After Medial Patellofemoral Ligament Reconstruction in Skeletally Immature Patients Compared With an Age- and Sex-Matched Cohort

BACKGROUND

Despite recent evidence that medial patellofemoral ligament reconstruction (MPFLR) in the skeletally immature patient is both safe and effective, there are limited data evaluating postoperative coronal- and sagittal-plane growth and radiographic patellofemoral parameters in this population.

PURPOSE

The primary purpose was to assess radiographic measures of coronal-plane alignment, longitudinal growth, patellar congruence, and trochlear dysplasia after MPFLR in a skeletally immature population. A secondary purpose was to assess this population compared with a matched cohort with a focus on trochlear dysplasia prevalence and the effect of MPFLR on patellar height.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

A total of 28 children with a minimum 1-year follow-up who underwent isolated MPFLR were identified. All patients were skeletally immature, defined as fully open physes on both sides of the knee joint, at the time of surgery. The development of a limb length discrepancy or angular growth abnormalities were assessed on standing hip-to-ankle radiographs, patellar tilt and congruence were measured on the Merchant view of the knee, and the grade of trochlear dysplasia and patellar height were assessed on lateral knee radiographs. A sex- and age-matched group of patients who underwent anterior cruciate ligament reconstruction was formed as a control for patellar height and trochlear dysplasia measurements.

RESULTS

The mean patient age was 11.71 ± 2.02 years at the time of surgery with a mean follow-up of 23.54 ± 12.49 months. All but 1 patient in the MPFLR group had preoperative features consistent with trochlear dysplasia. There was no significant difference in limb length or coronal-plane alignment at final follow-up (P = .725 and P > .999, respectively). Both the MPFLR and the anterior cruciate ligament reconstruction groups had a statistically significant decrease in the Caton-Deschamps index between the preoperative and postoperative time points (mean, 0.18 ± 0.20 and 0.11 ± 0.14, respectively; P = .161).

CONCLUSION

MPFLR may be safely performed utilizing an epiphyseal femoral socket in a skeletally immature cohort without affecting normal longitudinal growth or coronal limb alignment. The previously reported effect of MPFLR in reducing patellar height may be related to physiological growth based on similar changes noted in a comparison cohort that did not undergo the procedure.

Pediatric anterior cruciate ligament tears and associated lesions: Epidemiology, diagnostic process, and imaging

The incidence of anterior cruciate ligament injuries in skeletally immature patients has increased in recent years. The gold standard treatment of this type of trauma in children is not yet established. Conservative management may underestimate the risk of new meniscal and chondral tears; on the other hand, a more interventional approach may expose the patient to iatrogenic damage to the growth plate. A correct approach to the skeletally immature patient with knee trauma is therefore essential to guide the decision-making process. This review article aims to present an update on the epidemiology and diagnostic process of pediatric patients with anterior cruciate ligament tears and possible associated injuries. Level of Evidence: V.

Treatment of Symptomatic Subfibular Ossicle by Excision and Modified Broström Procedure for Skeletally Immature Patients

BACKGROUND

Ossicle resection combined with ligament repair using the modified Broström procedure (MBP) is generally associated with favorable results in adults with symptomatic subfibular ossicles; however, the surgical results of this approach in skeletally immature patients remain unclear. The purpose of this study was to investigate the midterm clinical outcomes and radiographic outcomes including leg length and physeal growth of skeletally immature patients after this procedure.

METHODS

Twenty-six consecutive skeletally immature patients who underwent ossicle resection combined with the MBP were retrospectively evaluated. Clinical scores were evaluated using the visual analog scale (VAS), American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot score, Karlsson-Peterson score, and Tegner score. The talocrural angle, fibular length on radiographs, and tape-measured leg length between the 2 ankles were also measured at the final follow-up. Time of return to sports and postoperative complications were also evaluated.

RESULTS

Fourteen girls (53.8%) and 12 boys (46.2%) had surgery at a mean age of 12.7±2.4 years. Mean postoperative follow-up time was 40.0±10.8 months. Mean VAS pain score improved from 4.1 preoperatively to 0.5 at final follow-up (P < .05). Mean AOFAS score, Karlsson score, and Tegner score all improved from 62.0, 54.0, and 2.8 preoperatively to 95.5, 94.0, and 5.4 (P < .05), respectively, at final follow-up. Median time of return to sports was 17.0 weeks. Mean talocrural angle, fibular length, and tape-measured leg length of the injured ankle were not significantly different from those of the contra-side at the final follow-up. All patients were satisfied with the results; repeat ligamentous injury occurred in 2 patients (7.7%). We had no cases of wound infection, nerve injury, compartment syndrome, or any other complications.

CONCLUSION

Ossicle resection combined with the MBP performed in skeletally immature patients with symptomatic subfibular ossicles resulted in improved clinical outcomes without disruption of fibular physeal growth by an average of 3.3-year follow-up.

LEVEL OF EVIDENCE

Level IV, case series.

Resorbable magnesium screws for fixation of medial epicondyle avulsion fractures in skeletally immature patients: A comparison with Kirschner wires

BACKGROUND

Displaced medial epicondyle fractures are treated with open reduction and internal fixation with K-wires or screws. Rates of implant prominence, failure, or non-union reported are considerable. Magnesium screws have demonstrated biocompatibility, osteoconductivity, and high pull-out strength. The aim of this study was to compare surgical fixation of medial epicondyle fracture using resorbable magnesium Herbert screws to K-wires, in skeletally immature patients.

METHODS

A retrospective analysis was performed from January 2015 to April 2020. Inclusion criteria were as follows displaced medial epicondyle fracture, <15 years, and absence of concomitant ipsilateral upper limb fractures. Two consecutive cohorts based on fixation device were made: Group A (wires) and Group B (magnesium screws). Alignment, pain, range of motion, Mayo Elbow Performance Score, and radiological healing were assessed.

RESULTS

A total of 27 patients were included: 15 in Group A and 12 in Group B. Groups were comparable for age and sex. Mean follow-up was higher in Group A (38.73 ± 3.15 vs 26.18 ± 4.85 months; p < 0.001). No significant differences were observed regarding range of motion, alignment, pain, and Mayo Elbow Performance Score, with excellent results in both groups. Two patients in Group A developed a deep wound pin site infection requiring antibiotics. X-rays revealed three cases of non-union in Group A and one in Group B, all of them asymptomatic. No patient required a second surgical procedure.

CONCLUSION

Open reduction and internal fixation of medial epicondyle fractures with magnesium screws showed comparable results to a widely accepted procedure such as the use of K-wires, potentially with a lower incidence of non-union and infection. No adverse reactions were recorded.

LEVEL OF EVIDENCE

level III.

Quantifying the Relationship Between the Medial Quadriceps Tendon-Femoral Ligament and Patellar Borders: A Pediatric Cadaveric Study

BACKGROUND

The medial patellofemoral complex (MPFC) is a structure composed of the medial quadriceps tendon-femoral ligament (MQTFL) superiorly and the medial patellofemoral ligament (MPFL) inferiorly. The pediatric MPFL anatomy has been well described, but the precise anatomy of the MQTFL has only recently been described and studied in skeletally immature patients.

PURPOSE

To describe the anatomic relationship between the MQTFL and its insertion on the quadriceps tendon and patella in pediatric specimens.

STUDY DESIGN

Descriptive laboratory study.

METHODS

A total of 22 pediatric cadaveric knee specimens were dissected to analyze attachment of the MQTFL to the quadriceps tendon and patella. Dissection was facilitated using lateral parapatellar arthrotomy followed by eversion of the extensor mechanism to evaluate MQTFL fibers from its undersurface.

RESULTS

The mean specimen age was 7.4 years. Specimens were divided based on age into a younger cohort (1-2 years), middle cohort (4-8 years), and older cohort (9-12 years). The quadriceps tendon attachment (QTA) of the MQTFL proximal to the patella extended a median of 5.0 mm in the younger cohort, 11.4 mm in the middle cohort, and 12.0 mm in the older cohort, with significant differences found between the younger and middle cohorts (P < .047) and the younger and older cohorts (P < .001). The QTA as a percentage of patellar articular height averaged 44.4% across all specimens. The vertical height of the patella measured a median of 14.0 mm, 22.3 mm, and 27.3 mm in the younger, middle, and older cohorts, respectively.

CONCLUSION

This study expands on the recently described anatomy of the pediatric MPFC to quantify the anatomic relationship between the MQTFL attachment to the quadriceps tendon and patella in a more clinically relevant cohort of donor specimens.

CLINICAL RELEVANCE

As access to pediatric cadaveric tissue is extremely limited, a better understanding of MPFC and MQTFL anatomy will support surgeons in preoperative planning and intraoperative considerations for their approach to MQTFL and MPFL reconstruction. This may facilitate improved anatomic surgical stabilization of the patellofemoral joint in pediatric patients.

Outcomes Following Primary Anterior Cruciate Ligament Reconstruction Using a Partial Transphyseal (Over-the-Top) Technique in Skeletally Immature Patients

BACKGROUND

The incidence of anterior cruciate ligament (ACL) injuries in skeletally immature patients is increasing, with ACL reconstruction preferred in this population due to reported chondroprotective benefits. Due to concerns with growth disturbance following ACL reconstruction in skeletally immature patients, various physealsparing and partial transphyseal techniques have been developed. Currently, there is no consensus on the most effective ACL reconstruction technique in skeletally immature patients. The purpose of the current study was to report the outcomes of a partial-transphyseal over-the-top (OTT) ACL reconstruction in a cohort of skeletally immature patients.

METHODS

All patients with radiographic evidence of open tibial and femoral physes that underwent primary ACL reconstruction using a partial-transphyseal OTT technique between 2009-2018 at a single tertiary-care institution with at least twelve months of clinical follow-up were retrospectively reviewed. Patient demographics, physical examination findings, graft ruptures, return to sport, and Tegner activity levels were analyzed. Statistical significance was defined as p<0.05.

RESULTS

Overall, 11 males and 1 female (12 knees) with a mean age of 12.8±1.8 (range: 10-16) years were included in the study. The mean postoperative follow-up of the cohort was 2.3±1.2 (range: 1.1-5.2) years. All ACLs were reconstructed with hamstring autograft with allograft augmentation utilized in a single patient. There were two cases of ACL graft rupture (16.7%). All patients were able to return to the same or higher level of sporting activity at an average of 7.4+2.7 months. There were no cases of clinically significant longitudinal or angular growth disturbance.

CONCLUSION

Partial transphyseal ACL reconstruction using a transphyseal tibial tunnel and an extra-articular OTT technique on the femur in skeletally immature patients affords minimal risk of growth disturbance with a graft rupture rate consistent with what has been reported in this high-risk population. All patients were able to return to sport at the same or higher level. Level of Evidence: IV.

Assessment of Skeletal Maturity and Postoperative Growth Disturbance After Anterior Cruciate Ligament Reconstruction in Skeletally Immature Patients: A Systematic Review

BACKGROUND

Growth disturbance is an uncommon but potentially serious complication after anterior cruciate ligament (ACL) reconstruction in skeletally immature patients.

PURPOSE

To describe how the pediatric ACL literature has assessed preoperative skeletal maturity and the amount of growth remaining and to comprehensively review the incidence, reporting, and monitoring of postoperative growth disturbance.

STUDY DESIGN

Systematic review; Level of evidence, 4.

METHODS

This review included studies reporting original research of clinical outcomes of skeletally immature patients after ACL reconstruction. Patient characteristics, surgical techniques, preoperative assessments of skeletal maturity or growth remaining, and postoperative assessments of growth disturbances were extracted.

RESULTS

A total of 100 studies met inclusion criteria. All studies reported chronological age, and 28 studies (28%) assessed skeletal age. A total of 44 studies (44%) used Tanner staging, and 12 studies (12%) obtained standing hip-to-ankle radiographs preoperatively. In total, 42 patients (2.1%) demonstrated a leg length discrepancy (LLD) >10 mm postoperatively, including 9 patients (0.5%) with LLD >20 mm; furthermore, 11 patients (0.6%) with LLD underwent growth modulation. Shortening was the most common deformity overall, but overgrowth was reported more frequently in patients who had undergone all-epiphyseal techniques. Most LLDs involved the femur (83%). A total of 26 patients (1.3%) demonstrated a postoperative angular deformity ≥5°, and 9 of these patients underwent growth modulation. The most common deformities were femoral valgus (41%), tibial recurvatum (33%), and tibial varus (22%). Although standing hip-to-ankle radiographs were the most common radiographic assessment of growth disturbance, most studies inadequately reported the clinical and radiographic methods of assessment for growth disturbance. Additionally, only 35% of studies explicitly followed patients to skeletal maturity.

CONCLUSION

This systematic review described significant variability in the reporting and monitoring of growth-related complications after ACL reconstruction in skeletally immature patients. The incidence of LLD and angular deformity appeared to be low, but the quality of research was not comprehensive enough for accurate assessment.

REGISTRATION

CRD42019136059 (PROSPERO).

Rigid intramedullary nail fixation of traumatic femoral fractures in the skeletally immature

Objective

To determine the rate of femoral head osteonecrosis, and other complications following rigid intramedullary (IM) nail fixation of traumatic diaphyseal femur fractures through the greater trochanter in the skeletally immature.

Design

Retrospective review, case series.

Setting

Level I academic trauma center.

Patients/Participants

One hundred forty-eight traumatic pediatric diaphyseal femur fractures in 145 patients treated with rigid IM nail fixation from November 1, 2004 to December 31, 2018.

Intervention

Rigid intramedullary nail fixation of traumatic diaphyseal femur fractures through a trochanteric start point in the skeletally immature.

Main outcome measurement

Rate of osteonecrosis of the femoral head.

Results

Sixty-five fractures in 64 skeletally immature patients met inclusion criteria. Motor vehicle collisions were implicated in 32 fractures. Of the 65 fractures, 5 were open. All rigid IM nails were anterograde with a trochanteric start point. Mean radiographic follow-up was 27.4 ± 8.1 months. Twenty-two patients experienced postoperative pain and/or hardware irritation, with 24 patients (36.9%) undergoing reoperation for hardware removal. No occurrences of infection, malunion, nonunion, refracture, venous thromboembolism, fat embolism, significant leg length discrepancy, or femoral head osteonecrosis were documented. Two cases of heterotopic ossification were observed, 1 requiring surgical excision, yielding a complication rate of 3.1%.

Conclusions

No cases of femoral head osteonecrosis were observed following treatment of 65 traumatic diaphyseal femur fractures with rigid IM nailing through the greater trochanter with a mean radiographic follow-up of 27 months. Rigid IM nail fixation with a trochanteric start point is both safe and efficacious for management of diaphyseal femur fractures in the skeletally immature.

Outcomes of Pediatric Posterior Cruciate Ligament Reconstruction: A Systematic Review

Background

Little has been reported in the literature regarding surgical treatment of posterior cruciate ligament (PCL) injuries in pediatric patients.

Purpose/Hypothesis

The purpose was to evaluate presentation, injury pattern, outcomes, and complications of surgically managed PCL injuries in pediatric patients. It was hypothesized that pediatric patients would have good patient-reported outcomes and no significant radiographic changes or complications.

Study Design

Systematic review; Level of evidence, 4.

Methods

A literature search was performed using PubMed, Medline, EMBASE, Scopus, and Cochrane databases between 1975 and December 16, 2019. Search terms included "posterior cruciate ligament," "peel-off injury," "avulsion," "PCL," "pediatric," "skeletally immature," and "adolescent." Included were studies on pediatric patients with PCL injuries managed operatively. Exclusion criteria included case reports, studies not reporting clinical results, reviews, abstract or conference papers, or papers not in the English language. Quality assessment was performed on all included studies using the MINORS (Methodological Index for Non-Randomized Studies) criteria.

Results

Four articles comprising 43 knees in 42 patients met the criteria and were included. Motor vehicle accidents were the most common mechanism of injury (39.5%; n = 17/43), followed by sports-related injuries (35%; n = 15/43). All studies commented on tear pattern, with the following distribution: 42% (n = 18/43) midsubstance tears, 37% (n = 16/43) tibial avulsions, and 21% (n = 9/43) femoral avulsions. Overall, good patient-reported outcomes (Knee injury and Osteoarthritis Outcome Score and Pediatric International Knee Documentation Committee, Tegner, and Lysholm scores) and return to activity, as well as satisfactory posterior stability (KT-1000 arthrometer, posterior drawer test, and kneeling radiographs) and range of motion, were reported. There was no significant leg-length discrepancy or angular deformity reported. Arthrofibrosis was reported in 7% of postoperative knees and was the most commonly reported complication. Osteoarthritis was reported in 21% (n = 9/43) of knees. The average MINORS score was 7 (range, 6-8) for noncomparative studies and 10 for comparative studies.

Conclusion

Good patient-reported outcomes and return to activity can be obtained using repair or reconstruction. This evidence was limited by the quality of the included studies and overall small sample size; however, this review serves as a baseline for futures studies on PCL repair/reconstruction in pediatric patients.

Influential Articles on Pediatric and Adolescent Anterior Cruciate Ligament Injuries: A Bibliometric Analysis

BACKGROUND

The understanding of pediatric anterior cruciate ligament (ACL) injuries and optimal treatment has evolved significantly. Influential articles have been previously evaluated using article citations to determine impact.

PURPOSE

To identify and characterize the 50 most cited and recent influential articles relating to pediatric and adolescent ACL injuries, to examine trends in publication characteristics, and to evaluate correlations of study citations with quality of evidence.

STUDY DESIGN

Cross-sectional study.

METHODS

The top 50 most cited articles on pediatric and adolescent ACL injuries were gathered using the Web of Science and Scopus online databases by averaging the number of citations from each database. Articles from recent years were also aggregated and sorted by citation density (citations/year). Publication and study characteristics were recorded. Level of evidence and methodologic quality were assessed where applicable using the modified Coleman Methodology Score (mCMS), modified Jadad scale, and Methodological Index for Non-Randomized Studies (MINORS). Spearman correlation was used to evaluate the association between citation data and level of evidence or methodologic quality scorings.

RESULTS

The top 50 cited papers had a mean of 117.5 ± 58.8 citations (range, 58.5-288.5 citations), with a mean citation density of 9.4 ± 5.4 citations per year (range, 2.9-25.8 citations/year); 80% were published in 2000 or later, and 6% were considered basic science. Articles were mainly level 4 evidence (27/42; 64.3%), and none was level 1. There were moderate, significant associations between publication year and level of evidence (r S = -0.45; P = .0030) and citation density and publication year (r S = 0.59; P < .001). Mean methodologic quality scores were as follows: mCMS, 53 ± 7.2 (range, 39-68); modified Jadad scale, 3.2 ± 1.1 (range, 2-6); and MINORS, 11.2 ± 3.2 (range, 6-20). There was a significant, strong correlation between rank of mean citations and modified Jadad scale (r S = 0.76; P < .0001), suggesting poorer score associated with more mean citations.

CONCLUSION

Influential articles on pediatric and adolescent ACL injuries were relatively recent, with a low proportion of basic science-type articles. Most of the studies had a lower evidence level and poor methodologic quality scores. Higher methodologic quality did not correlate positively with citation data.

Quantitative assessment of the vascularity of the skeletally immature patella: a cadaveric study using MRI

PURPOSE

While predominant blood supply to the adult patella enters inferomedially, little is known about skeletally immature patellar perfusion. Improved knowledge of immature patella vascularity can further understanding of osteochondritis dissecans, dorsal defects of the patella and bipartite patella, and help ensure safe surgical approaches. We hypothesized that the immature patella would exhibit more uniform blood flow. The study purpose was to quantify immature patella regional perfusion in comparison with adults.

METHODS

Ten cadaveric knees were utilized (five immature, five mature). The superficial femoral artery was cannulated proximally. Signal enhancement increases were compared from pre- to post-contrast MRI to assess relative arterial contributions to patella regions (quadrants, anterior/posterior, superior/inferior, medial/lateral, and outer/inner).

RESULTS

Quantitative-MRI analysis revealed similar distribution of enhancement between the immature and mature patella. The inferior pole exhibited significantly higher arterial contribution versus superior pole in both immature and mature groups (p = 0.009; both groups), while the inferomedial quadrant had the highest arterial contribution of all quadrants in both groups. The superolateral quadrant demonstrated the lowest arterial contribution in the immature group and second lowest in the adult group. The patella outer periphery had significantly greater arterial contribution than the inner central region in both immature (p = 0.009) and mature (p = 0.009) groups.

CONCLUSION

Distribution of arterial contributions between the immature and mature patella was similar. Our results highlight the importance of inferior and inferomedial blood supply in both immature and mature patellas. These findings have implications for paediatric and adult patients; surgical damage to inferior patellar vessels should be avoided to prevent associated complications.

Towards Standardization in the Diagnostic Evaluation of ACL Injuries in Skeletally Immature Patients

The purpose of this study was to establish consensus regarding a standardized approach to the diagnostic evaluation of ACL tears in pediatric/adolescent patients. Despite an abundance of literature evaluating management techniques, no standardized consensus exists regarding evaluation in these patients. A three-step classic Delphi technique was employed. The panel included 12 Orthopaedic Sports Medicine specialists from across the United States with training in pediatric and adult ACL injuries. Panelists were presented with four clinical vignettes. Consensus was established if ≥66% of respondents reached agreement. Across all four rounds of this study, 100% participation was achieved, and consensus was reached for a majority of diagnostic domains. For history, previous injuries, sports participation, and current symptoms were endorsed for all vignettes. The consensus radiographic sequences across all four vignettes included: standing AP, flexion (tunnel or notch view), lateral, long-leg alignment, and bone age (left hand) views. Radiographic interpretation responses met consensus with interpretations were split by gender. Cross-sectional imaging met consensus with 100% support for MRI. In this Delphi study, we identified a standardized diagnostic treatment approach derived from expert opinion applicable to all skeletally immature patients with ACL tears, which can serve as a framework for evaluation to aid clinical decision making.

Relationship of the Medial Patellofemoral Ligament Origin on the Distal Femur to the Distal Femoral Physis: A Systematic Review

BACKGROUND

The relationship between the medial patellofemoral ligament (MPFL) and the distal femoral physis has been reported in multiple studies.

PURPOSE

To determine the distance from the MPFL central origin on the distal femur to the medial distal femoral physis in skeletally immature participants.

STUDY DESIGN

Systematic review.

METHODS

A systematic review was performed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Multiple databases were searched for studies investigating the anatomic origin of the MPFL on the distal femur and its relationship to the medial distal femoral physis in skeletally immature participants. Study methodological quality was analyzed with the Anatomical Quality Assessment tool, with studies categorized as low risk, high risk, or unclear risk of bias. Continuous variable data were reported as mean ± SD. Categorical variable data were reported as frequency with percentage.

RESULTS

Seven articles were analyzed (298 femurs, 53.7% male patients; mean age, 11.7 ± 3.4 years). There was low risk of bias based on the Anatomical Quality Assessment tool. The distance from the MPFL origin to the distal femoral physis ranged from 3.7 mm proximal to the physis to 10.0 mm distal to the physis in individual studies. Six of 7 studies reported that the MPFL origin on the distal femur lies distal to the medial distal femoral physis in the majority of specimens. The MPFL originated distal to the medial distal femoral physis in 92.8% of participants at a mean distance of 6.9 ± 2.4 mm.

CONCLUSION

The medial patellofemoral ligament originates distal to the medial distal femoral physis in the majority of cases at a mean proximal-to-distal distance of 7 mm distal to the physis. However, this is variable in the literature owing to study design and patient age and sex.

Comparison of Ligament Isometry and Patellofemoral Contact Pressures for Medial Patellofemoral Ligament Reconstruction Techniques in Skeletally Immature Patients

BACKGROUND

Adult medial patellofemoral ligament (MPFL) reconstruction techniques are not appropriate for the skeletally immature patient given the proximity of the distal femoral physis. Biomechanical consequences of reconstructions aimed at avoiding the physis have not been adequately studied.

PURPOSE

To quantify the biomechanical effects of MPFL reconstruction techniques intended for skeletally immature patients.

STUDY DESIGN

Controlled laboratory study.

METHODS

Four MPFL reconstruction techniques were evaluated using a computationally augmented cadaveric model: (1) Schoettle point: adult-type reconstruction; (2) epiphyseal: socket distal to the femoral physis; (3) adductor sling: graft wrapped around the adductor tendon; (4) adductor transfer: adductor tendon transferred to patella. A custom testing frame was used to cycle 8 knees for each technique from 10° to 110° of flexion. Patellofemoral kinematics were recorded using a motion camera system, contact stresses were recorded using Tekscan pressure sensors, and MPFL length was computed using an inverse kinematics computational model. Change in MPFL length, patellar facet forces, and patellar kinematics were compared using generalized estimating equation modeling.

RESULTS

Schoettle point reconstruction was the most isometric, demonstrating isometry from 10° to 100°. The epiphyseal technique was isometric until 60°, after which the graft loosened with increasing flexion. The adductor sling and adductor transfer techniques were significantly more anisometric from 40° to 110°. Both grafts tightened with knee flexion and resulted in significantly more lateral patellar tilt versus the intact state in early flexion and significantly higher contact forces on the medial facet versus the epiphyseal technique in late flexion.

CONCLUSION

In this cadaveric simulation, the epiphyseal technique allowed for a more isometric ligament until midflexion, when the patella engaged within the trochlear groove. The adductor sling and adductor transfer grafts became tighter in flexion, resulting in potential loss of motion, pain, graft stretching, and failure. Marginal between-condition differences in patellofemoral contact mechanics and patellar kinematics were observed in late flexion.

CLINICAL RELEVANCE

In the skeletally immature patient, using an epiphyseal type MPFL reconstruction with the femoral attachment site distal to the physis results in a more isometric graft compared with techniques with attachment sites proximal to the physis.

Use Caution When Assessing Preoperative Leg-Length Discrepancy in Pediatric Patients With Anterior Cruciate Ligament Injuries

BACKGROUND

Pre- and postoperative standing hip-to-ankle radiographs are critical for monitoring potential postoperative growth arrest and resultant deformities after pediatric anterior cruciate ligament (ACL) reconstruction.

PURPOSE

To determine the prevalence of apparent preoperative leg-length discrepancies (LLDs) that resolve at the first postoperative radiographic examination in patients undergoing ACL reconstruction in order to understand what proportion of the noted preoperative deformities may have been inaccurate.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

A retrospective review of prospectively collected preoperative and first postoperative full-length hip-to-ankle radiographs was performed in a cohort of skeletally immature patients who had an acute ACL injury and underwent subsequent surgical reconstruction. Leg length measurements for both the injured and the uninjured legs were obtained for comparison.

RESULTS

A total of 112 patients (mean age, 12.7 ± 1.7 years) were included (79 boys and 33 girls). Leg-length measurement interrater reliability among 3 raters for 25 randomly chosen images was nearly perfect (intraclass correlation coefficient, 0.996; 95% CI, 0.994-0.998). At baseline, there was no apparent preoperative LLD (<5 mm) in 48% (n = 54) of participants, while 37% (n = 41) displayed a small apparent LLD (5 to <10 mm), 12% (n = 13) displayed a moderate apparent LLD (10 to <15 mm), and 4% (n = 4) displayed a large apparent LLD (≥15 mm). Of the patients with an apparent preoperative LLD, 66% (n = 38) of them tore their ACL on the leg measuring shorter. At first postoperative radiographs, 48% (n = 28) of patients with an apparent preoperative LLD showed resolution to no LLD: 46% (n = 19) of patients with a small apparent preoperative LLD, 54% (n = 7) of patients with a moderate apparent LLD, and 50% (n = 2) of patients with a large apparent LLD.

CONCLUSION

A high percentage of patients (48%) with apparent preoperative LLDs showed resolution to no LLDs by their first postoperative imaging, indicating that preoperative hip-to-ankle radiographs display some false LLDs in patients with recent ACL tears who are unable to fully extend their injured leg and bear weight.

The Association of Finger Growth Plate Injury History and Speed Climbing in Youth Competition Climbers

INTRODUCTION

Finger growth plate injuries are the most common injury among youth climbers, and the association between these injuries and speed climbing, a mandatory discipline in the 2021 Olympics, has not been examined previously. Our primary purpose was to examine the demographic and training characteristics of adolescent competition climbers who reported a history of a finger growth plate injury compared to those who did not report a history of a finger growth plate injury. Our secondary purpose was to determine whether training characteristics differed between adolescent competition climbers who did and did not report speed climbing.

METHODS

Our study was a cross-sectional study design. We surveyed adolescent climbers who competed in the 2017 USA Climbing Sport and Speed Youth National Championships. Questions assessed climbing injury history and current rock-climbing training characteristics.

RESULTS

Two-hundred sixty-seven adolescent competition climbers, 14±3 (9-18) y of age (mean±SD with range), completed the survey. Those with a history of a finger growth plate injury reported greater approximate time spent speed climbing throughout the year (β=1.28, 95% CI 0.11-2.46, P=0.032) and training regularly on the International Federation of Sport Climbing speed wall (adjusted odds ratio=3.95, 95% CI 1.14-13.7, P=0.031).

CONCLUSIONS

Training regularly at practices on the speed wall was associated with a self-reported history of finger growth plate injuries among elite youth competition climbers. Speed climbing should be limited, especially during periods of rapid growth.

Osteochondritis Dissecans of the Knee: An Interrater Reliability Study of Magnetic Resonance Imaging Characteristics

BACKGROUND

Imaging characteristics of osteochondritis dissecans (OCD) lesions quantified by magnetic resonance imaging (MRI) are often used to inform treatment and prognosis. However, the interrater reliability of clinician-driven MRI-based assessment of OCD lesions is not well documented.

PURPOSE

To determine the interrater reliability of several historical and novel MRI-derived characteristics of OCD of the knee in children.

STUDY DESIGN

Cohort study (diagnosis); Level of evidence, 3.

METHODS

A total of 42 OCD lesions were evaluated by 10 fellowship-trained orthopaedic surgeons using 31 different MRI characteristics, characterizing lesion size and location, condylar size, cartilage status, the interface between parent and progeny bone, and features of both the parent and the progeny bone. Interrater reliability was determined via intraclass correlation coefficients (ICCs) with 2-way random modeling, Fleiss kappa, or Krippendorff alpha as appropriate for each variable.

RESULTS

Raters were reliable when the lesion was measured in the coronal plane (ICC, 0.77). Almost perfect agreement was achieved for condylar size (ICC, 0.93), substantial agreement for physeal patency (ICC, 0.79), and moderate agreement for joint effusion (ICC, 0.56) and cartilage status (ICC, 0.50). Overall, raters showed significant variability regarding interface characteristics (ICC, 0.25), progeny (ICC range, 0.03 to 0.62), and parent bone measurements and qualities (ICC range, -0.02 to 0.65), with reliability being moderate at best for these measurements.

CONCLUSION

This multicenter study determined the interrater reliability of MRI characteristics of OCD lesions in children. Although several measurements provided acceptable reliability, many MRI features of OCD that inform treatment decisions were unreliable. Further work will be needed to refine the unreliable characteristics and to assess the ability of those reliable characteristics to predict clinical lesion instability and prognosis.

Pediatric Anterior Cruciate Ligament Reruptures Are Related to Lower Functional Scores at the Time of Return to Activity: A Prospective, Midterm Follow-up Study

Background:

Skeletally immature patients show a higher rate of anterior cruciate ligament (ACL) reruptures. A better understanding of the risk factors for an ACL rerupture in this population is critical.

Purpose/Hypothesis:

The objective of this study was to analyze preoperative, intraoperative, and postoperative characteristics of pediatric patients undergoing ACL reconstruction and determine the relationship of these factors with an ACL rerupture. It was hypothesized that patients with worse activity scores and knee function at the time of return to activity would have a higher rate of ACL reruptures at midterm follow-up. Additionally, it was hypothesized that most ACL reruptures would occur before age 20 years in the study population.

Study Design:

Case-control study; Level of evidence, 3.

Methods:

A total of 65 skeletally immature patients (age <16 years) with ACL ruptures underwent reconstruction with a quadruple hamstring tendon graft between 2002 and 2016. Of these patients, 52 were available for the study. Patient characteristics, surgical details, Tegner and Lysholm scores, and ACL reconstruction outcomes were recorded. Patients were analyzed and compared according to ACL rerupture occurrence.

Results:

Of the 52 patients, 18 (34.6%) experienced an ACL rerupture after reconstruction. The majority of reruptures (77.8%) occurred before age 20 years. There were 2 patients who sustained ACL reruptures during the rehabilitation period before they returned to activity. The majority of reruptures occurred after 12 months (83.2%), with 66.6% occurring after 24 months. Upon returning to activity between 6 and 9 months postoperatively, patients who ended up with intact ACL grafts reported 69% higher mean Tegner scores (P = .006) and 64% higher mean Lysholm scores than patients who sustained ACL reruptures (P < .001). Within the limits of this study, we could identify no statistical relationship between the rate of ACL reruptures and different sport types, surgical techniques, or associated injuries (P > .05).

Conclusion:

Skeletally immature patients who underwent ACL reconstruction and sustained ACL reruptures had lower Tegner and Lysholm scores upon returning to activity than patients without ACL reruptures. In addition, most ACL reruptures occurred in patients younger than 20 years (77.8%) and after 24 months postoperatively (66.6%).

Transphyseal Anterior Cruciate Ligament Reconstruction in the Skeletally Immature: Quadriceps Tendon Autograft Versus Hamstring Tendon Autograft

Background:

It is unclear what the optimal graft choice is for performing anterior cruciate ligament (ACL) reconstruction in a skeletally immature patient.

Purpose:

To evaluate outcomes and complications of skeletally immature patients undergoing transphyseal ACL reconstruction with a hamstring tendon autograft versus a quadriceps tendon autograft.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

Between 2012 and 2016, 90 skeletally immature patients from a single institution underwent primary transphyseal ACL reconstruction with either a quadriceps tendon autograft or a hamstring tendon autograft based on surgeon preference (n = 3). Patient demographic, injury, radiographic, and surgical variables were documented. Outcome measures included the Lysholm score, Single Assessment Numeric Evaluation (SANE), Tegner activity score, pain, satisfaction, and complications such as graft tears and physeal abnormalities.

Results:

A total of 83 patients (56 hamstring tendon, 27 quadriceps tendon) were available for a minimum follow-up of 2 years or sustained graft failure. The mean age of the patients was 14.8 ± 1.4 years at the time of ACL reconstruction. No differences in chronological age, bone age, sex, patient size, or mechanism of injury were noted between groups. There were no differences in surgical variables, except that the quadriceps tendon grafts were larger than the hamstring tendon grafts (9.6 ± 0.6 mm vs 7.8 ± 0.7 mm, respectively; P < .001). Patient outcomes at a mean follow-up of 2.8 ± 0.9 years revealed no differences based on graft type, with mean Lysholm, SANE, pain, satisfaction, and Tegner scores of 96, 93, 0.6, 9.6, and 6.6, respectively, for the quadriceps tendon group and 94, 89, 0.9, 9.2, and 7.1, respectively, for the hamstring tendon group. While there were no physeal complications in either group, patients undergoing ACL reconstruction with a hamstring tendon autograft were more likely to tear their graft (21% vs 4%, respectively; P = .037).

Conclusion:

Skeletally immature patients undergoing ACL reconstruction can be successfully managed with either a quadriceps tendon autograft or a hamstring tendon autograft with good short-term outcomes, high rates of return to sport, and low rates of physeal abnormalities. The primary differences between grafts were that the quadriceps tendon grafts were larger and were associated with a lower retear rate. ACL reconstruction performed with a quadriceps tendon autograft may reduce early graft failure in skeletally immature patients.

Medial Patellofemoral Ligament Reconstruction in Skeletally Immature Patients: A Systematic Review and Meta-analysis

BACKGROUND

Given the proximity of the medial patellofemoral ligament (MPFL) femoral insertion to the distal femoral physis in skeletally immature patients, multiple techniques for femoral graft fixation have been described.

PURPOSE

To systematically review the literature and evaluate outcomes and complications following MPFL reconstruction in skeletally immature patients.

STUDY DESIGN

Systematic review; Level of evidence, 4.

METHODS

A comprehensive literature search was performed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines through use of the PubMed, Embase, and Cochrane Central databases. All original, English-language studies reporting outcomes or complications following MPFL reconstruction in skeletally immature patients were included. Skeletally mature patients were excluded. Data regarding demographics, surgical technique, graft type, outcomes, and complications were recorded. Study quality was assessed by use of the modified Coleman methodology score. Statistical analysis was performed through use of chi-square and weighted mean pooled cohort statistics, where appropriate, with significance set at P < .05.

RESULTS

7 studies that entailed 132 MPFL reconstructions (126 patients) met the inclusion criteria. Females comprised 57.9% of the cohort (73 females), and the mean age was 13.2 years (range, 6-17 years). Mean postoperative follow-up was 4.8 years (range, 1.4-10 years). All of the grafts used were autograft, with gracilis tendon (n = 80; 60.6%) being the most common. Methods of femoral fixation included interference screw (n = 52; 39.4%), suture anchor (n = 51; 38.6%), and soft tissue pulley around the medial collateral ligament or adductor tendon (n = 29; 21.9%). Pooled Kujala scores improved from 59.1 to 84.6 after MPFL reconstruction. The total reported complication rate was 25.0% (n = 33) and included 5 redislocations (3.8%) and 15 subluxation events (11.4%). No cases of premature physeal closure were noted, and there were 3 reports of donor site pain (2.3%). Neither autograft choice (P > .804) nor method of femoral fixation (P > .416) influenced recurrent instability or overall complication rates.

CONCLUSION

These findings suggest that MPFL reconstruction in skeletally immature patients is a viable treatment option, with significant improvement in patient-reported outcomes and redislocation event rates of less than 5% at nearly 5-year follow-up. Further high-quality research is needed to determine optimal graft options and surgical technique while considering recurrent instability, donor site morbidity, and potential injury to the adjacent physis.

Comparing Outcomes Between the Over-the-Top and All-Epiphyseal Techniques for Physeal-Sparing ACL Reconstruction: A Narrative Review

A variety of techniques are used for physeal-sparing anterior cruciate ligament (ACL) reconstruction; however, there is no clear consensus on the ideal surgical technique, the frequency of complications, and how to best avoid growth disturbance. The purpose of this study was to compare outcomes and complications between over-the-top and all-epiphyseal ACL reconstruction techniques. The hypothesis was that both physeal-sparing reconstruction techniques are efficacious, with similar risk of growth disturbance and complications. The Embase and PubMed databases were queried for studies on ACL ruptures in the skeletally immature population from 1985 to 2018. Full-text English studies were included (N = 160). Studies reporting rerupture and/or complications after physeal-sparing ACL reconstruction, specifically growth disturbance, were included (n = 10). Studies were separated into 2 groups: an all-epiphyseal group with femoral and tibial fixation points within the epiphysis and a group that had over-the-top femoral and tibial physeal-sparing reconstruction. Complications not specific to the pediatric population were excluded. Demographics, evaluation of skeletal maturity, surgical technique, growth disturbance, rerupture, and patient-reported outcome scores were collected. Data were analyzed in aggregate. The 10 studies included 482 knees. The mean age was 12.0 years; 81% of patients were male; and mean follow-up was 47.7 months. A total of 178 patients underwent all-epiphyseal reconstruction, and 298 had the femoral graft placed over the top. The rerupture rate was 9.0% (16 of 178) in the all-epiphyseal group and 7.2% (14 of 195) in the over-the-top group, of which 82% required revision reconstruction. Six patients had overgrowth in the all-epiphyseal group (mean, 1.8 cm) and 1 patient in the over-the-top group (1.5 cm). Three angular deformities occurred, all of which were in the over-the-top group. Both physeal-sparing ACL reconstruction techniques are successful. Overgrowth was more common in the all-epiphyseal group and angular deformity in the over-the-top group. Rerupture rates were similar between the groups. The authors recommend standardization of skeletal age assessment and baseline lower extremity alignment films.

Computer Navigation for Pediatric Femoral ACL Tunnel Placement

BACKGROUND

To compare accuracy, time and radiation exposure of pediatric femoral tunnel placement using computer navigation with a traditional freehand technique.

METHODS

A single all-epiphyseal femoral tunnel was placed in the distal femur of 20 Sawbones™ adolescent knee models. Ten tunnels were drilled using standard fluoroscopic guidance (FG). An additional 10 tunnels were drilled using 3D fluoroscopic computer navigation (CN). Both techniques aimed to match an exact point described by the quadrant system of Bernard. Time to perform the procedure was recorded as were number of single shot fluoroscopic images and approximate effective radiation doses.

RESULTS

The deviation from ideal femoral tunnel position was on average 6.4 ± 4.2 mm for FG tunnels and 2.7 ± 3.1 mm for CN tunnels (p<0.05) . There was no violation of the femoral growth plate using either technique. The surgeon was exposed to 17 ± 5.3 and 3 ± 0.66 single fluoroscopy exposures for FG and CN guidance, respectively (p<0.05). However, the effective dose for the CN because of the acquisition of 3D images was 0.52±.003 mSv and for FG was only 0.09mSv ± .027 (p <0.001). CN however required on average 12.5 ± 3.4 min compared to 4.6 ± 1.7 for FG (p<0.05) to complete drilling of the tunnel.

CONCLUSON

CN achieves a more accurate epiphyseal femoral ACL tunnel position but requires more time to complete and has a higher effective radiation dose than FG. Whether the CN ACL tunnels can translate to improved clinical outcomes is still unknown.Level of Evidence: V.

Factors Affecting the Preferred Surgical Technique in Pediatric Anterior Cruciate Ligament Reconstruction

Background

Despite several well-described operative techniques, the optimal management of anterior cruciate ligament (ACL) injuries in pediatric patients remains unclear.

Purpose

To identify surgeons' preferred ACL reconstruction techniques and postoperative protocols for pediatric patients of various ages.

Study Design

Cross-sectional study.

Methods

An electronic survey was administered to surgeons in the Pediatric Research in Sports Medicine (PRiSM) society, resulting in a cohort of experienced respondents who performed a relatively high volume of ACL reconstructions in skeletally immature patients. Surgeon and practice demographic information was recorded. The survey presented the scenario of a patient who had a physical examination and imaging consistent with an acute, isolated ACL tear. The respondents were asked to select their preferred reconstruction technique for female and male patients at consecutive skeletal ages from 8 to 15 years. Surgeons were also asked about postoperative protocol.

Results

Of 103 surgeons, 88 (85%) responded to the survey, the majority of whom (68%) performed more than 25 pediatric ACL reconstructions annually. The greatest variation in technique was from ages 11 to 13 years in female patients and from 11 to 14 years in male patients. The modified MacIntosh was the most frequently used technique for patients aged 8 to 10 years. An all-epiphyseal technique was preferred over a broader age range in male patients than female patients, with peak use at age 11 in both. A partial transphyseal (hybrid) technique was preferred in slightly older patients, with peak use at age 12 in female patients and 13 in male patients. The transphyseal technique was most widely used at age 13 and older in female patients and 14 and older in male patients. The impact of fellowship training (pediatrics, sports, or both) on technique preference was statistically significant for male patients aged 11 to 13 and female patients 11 and 12 (all P < .05). Surgeons with pediatric orthopaedic training tended to prefer an all-epiphyseal reconstruction, while those with both pediatric and sports medicine training preferred the modified MacIntosh.

Conclusion

The preferred ACL reconstruction technique varied considerably, especially for patients aged 11 to 13 years. The modified MacIntosh reconstruction was favored in patients aged 10 years or younger, while the transphyseal technique was preferred in female patients aged 13 years and older and in male patients 14 years and older. The surgeon's fellowship training was significantly associated with his or her preferred surgical technique.

Biomechanical Comparison of Epiphyseal Anterior Cruciate Ligament Fixation Using a Cortical Button Construct Versus an Interference Screw and Sheath Construct in Skeletally Immature Cadaveric Specimens

Background:

Anterior cruciate ligament (ACL) ruptures have become increasingly common in pediatric and adolescent athletes. While multiple methods exist, all-epiphyseal ACL reconstruction is a popular technique in the skeletally immature patient. Given the high rate of reruptures in this population and the increasing number of commercially available fixation devices, biomechanical testing is crucial to understand the performance of these devices in pediatric epiphyseal bone. To our knowledge, there has not been a biomechanical analysis of ACL fixation devices in skeletally immature bone.

Purpose:

To compare cortically based button fixation with interference screw and sheath fixation in skeletally immature femoral epiphyseal cadaveric bone. Our hypothesis was that there would be no difference in peak load to failure, stiffness, or cyclic displacement between these 2 fixation constructs.

Study Design:

Controlled laboratory study.

Methods:

Fresh-frozen matched-pair knees from 3 pediatric cadaveric specimens were obtained. A synthetic graft was fixed in an all-epiphyseal femoral tunnel. Both the lateral and medial condyles were utilized to increase the sample size. Specimens were randomized and assigned to receive either an interference screw and sheath construct designed for pediatric patients or an adjustable loop cortical button. Biomechanical testing was performed to obtain ultimate load to failure, stiffness, total displacement after 500 cycles, and the failure mode for each condyle.

Results:

Each medial and lateral condyle in 3 pairs of skeletally immature cadaveric knees (ages 7, 9, and 11 years) was utilized for testing. One specimen was excluded after it failed by having a transphyseal fracture. The median peak load to failure was 769.80 N (interquartile range [IQR], 628.50-930.41 N) for the screw and sheath group and 862.80 N (IQR, 692.34-872.65 N) for the button group (P = .893). The median displacement after 500 cycles for the screw and sheath group was 0.65 mm (IQR, 0.47-1.03 mm) and 1.13 mm (IQR, 0.96-1.25 mm) for the button group (P = .08). The median stiffness of the screw and sheath group was significantly higher than that of the button group (31.47 N/mm [IQR, 26.40-43.00 N/mm] vs 25.22 N/mm [IQR, 21.18-27.07 N/mm], respectively) (P = .043).

Conclusion:

When comparing femoral fixation with a screw and sheath construct developed for pediatric patients to an adjustable loop cortical button in skeletally immature bone, our results showed that fixation did not significantly differ with respect to cyclic displacement or peak load to failure. While the screw and sheath construct was significantly stiffer, its effect on clinical outcomes is not yet known.

Clinical Relevance:

With regard to femoral fixation, there is no significant biomechanical difference between the use of cortically based button fixation or interference screw and sheath fixation in pediatric epiphyseal cadaveric bone.

Bone Bruise Patterns in Skeletally Immature Patients With Anterior Cruciate Ligament Injury: Shock-Absorbing Function of the Physis

BACKGROUND

Bone bruises are frequently found on magnetic resonance imaging (MRI) after anterior cruciate ligament (ACL) injury and have been related to the force associated with the trauma. Yet, little is known about the bone bruise distribution pattern of skeletally immature (SI) patients, as the presence of an open physis may play a role in energy dissipation given its unique structure.

PURPOSE

To describe and compare the location and distribution of tibial and femoral bone bruises, observed on MRI, between 2 groups of ACL-injured knees: the first group with an open physis and the second with a closed physis. Additionally, based on the bone bruise distribution pattern, the secondary aim of the study was to propose a new classification of bone bruise in SI patients.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

A retrospective review was conducted to identify all cases of primary ACL tears in patients ≤16 years old, with MRI within 6 weeks of injury between January 2012 and December 2016. Overall, 106 patients were identified: 53 with open physis (skeletally immature [SI] group) and 53 with closed physis as control (skeletally mature [SM] group). MRI scans were reviewed to assess for the presence and location of bone bruises. Longitudinal bone bruise distribution was described as epiphyseal and metaphyseal in both femur and tibia. The proposed classification for tibia and femur has 2 parts: the location of the bone bruise in the (I) lateral, (II) medial, or (III) medial and lateral parts of the bone; and if the bone bruise (a) does not or (b) does cross the physis. For the tibia, if the bone bruise is also present in the central portion, a letter C is added.

RESULTS

The SI group had significantly fewer bone bruises cross the physis and extend into the metaphysis than did the SM group for both the tibia (25% vs 85%, respectively; P < .0001) and the femur (4% vs 42%; P < .0001). The most common patterns observed in the SI group were type IIICa in the tibia (medial/lateral and central, not extending into the metaphysis: 42%) and type Ia in the femur (lateral, not extending into the metaphysis: 59%).

CONCLUSION

The data from this study shows that patients with an open physis at the occurrence of an acute ACL rupture have unique bone bruise patterns as compared with those with a closed physis. In the SI patients, the bone bruise pattern is significantly less frequently observed in the tibial and femoral metaphysis.

Anterior Cruciate Ligament Reconstruction in Skeletally Immature Patients: Early Results Using a Hybrid Physeal-Sparing Technique

Background:

Reconstruction of the anterior cruciate ligament (ACL) in the skeletally immature patient is frequently performed in hopes of preventing new or additional chondral damage and meniscal injuries. Patients within a few years of skeletal maturity are more at risk for ACL injuries than prepubescent patients, about whom several physeal-sparing techniques have been described. Reconstruction techniques in the former higher risk group need to be better understood.

Purpose:

To review a series of adolescent patients with ACL injuries surgically treated with the hybrid physeal-sparing technique.

Study Design:

Case series; Level of evidence, 4.

Methods:

Surgical logs of ACL reconstructions (ACLRs) performed at a single pediatric/adolescent sports medicine center over a 6-year period were reviewed. Patients with open physes who had undergone ACLR with a femoral physeal-sparing tunnel and transphyseal tibial tunnel were identified. Their demographics, operative reports, rehabilitative course, time to return to play, outcome scores, and postoperative radiographs were collected and analyzed.

Results:

Twenty-three patients with a mean chronological age and bone age of 13.0 and 13.6 years, respectively, were identified. Examination and subjective outcome scores were obtained at a mean of 19 months and overall demonstrated positive results, with a mean Pediatric International Knee Documentation Committee (Pedi-IKDC) score of 96.0 and a mean Anterior Cruciate Ligament–Return to Sport after Injury (ACL-RSI) score of 89.1. Full-length mechanical axis films obtained at a mean 21 months postoperatively demonstrated no leg-length discrepancies or angular deformities in 21 of 23 patients. Two patients had an identified growth disturbance in the form of femoral and tibial growth acceleration on the ACL-reconstructed limb.

Conclusion:

The femoral physeal-sparing with transphyseal tibial drilling “hybrid” technique in skeletally maturing patients appears to have a high rate of success with low morbidity. However, the possibility of physeal abnormalities does exist, which demonstrates the importance of a close postoperative follow-up and evaluation until skeletal maturity is achieved. ACLR in skeletally immature patients is performed on an increasingly regular basis. Establishing the best and safest technique to do so is therefore important.

Evaluation of the Schöttle Technique in the Pediatric Knee

Background

The Schöttle point is commonly used for anatomic femoral tunnel placement during medial patellofemoral ligament (MPFL) reconstruction. This technique has not been previously validated in the skeletally immature patient, in whom femoral tunnel placement may put the distal femoral physis at risk of iatrogenic injury.

Hypothesis

Interobserver reliability for femoral tunnel placement will be higher in adult knees compared with pediatric knees.

Study Design

Cross-sectional study (diagnosis); Level of evidence, 3.

Methods

We selected 30 perfect lateral radiographs for this study: 20 from pediatric knees (mean patient age, 10 years; range, 8-11 years) and 10 from adult knees (mean patient age, 18.5 years; range, 18-23 years). Six observers with varying levels of clinical experience evaluated each radiograph and approximated the site of the MPFL femoral tunnel using the Schöttle technique. Intra- and interobserver reliabilities for femoral tunnel placement were evaluated. Statistical analysis was used to compare measurements.

Results

During initial interobserver measurements, the diameter of the composite perfect circles averaged 9.0 and 6.8 mm in adult and pediatric knees, respectively (P = .004). At repeat measurement, circles averaged 9.8 and 7.3 mm in adult and pediatric knees, respectively (P = .0001). Femoral tunnel placement intraobserver variance averaged 2.9 mm in adult knees (range, 1.9-4.0 mm) and 2.3 mm in pediatric knees (range, 1.9-2.9 mm). This difference was not significant (P = .14).

Conclusion

This study demonstrated that interobserver variance is actually greater in adult knees compared with pediatric knees, although interobserver variance was significantly different for both populations. Additionally, intraobserver variance is small on repeat measures, demonstrating that the Schöttle technique is reproducible for individual observers. Sources of this increased variance between observers are differences in agreement on the bony landmarks required for the Schöttle technique. Due to this variability in tunnel placement, we recommend caution when the Schöttle technique is used in pediatric knees to avoid iatrogenic injury to the distal femoral physis during femoral tunnel placement.

Prevention, treatment, and rehabilitation of anterior cruciate ligament injuries in children

As more children and adolescents participate in competitive organized sports, there has been an increase in the reported incidence of anterior cruciate ligament (ACL) injuries in these age groups. ACL injuries in skeletally immature athletes present a challenge, as reconstruction must preserve the physis of the distal femur and of the proximal tibia to avoid growth disturbances. Historically, a skeletally immature athlete with an ACL injury was treated with a brace and activity modification until skeletal maturity, with ACL reconstruction being performed at that time in the “non-copers” who experienced instability. More recently, evidence has shown that delayed reconstruction may lead to increased damage to the meniscus and articular cartilage. As a result, early reconstruction is favored to protect the meniscus and allow continued physical activity. While adolescents at or those near skeletal maturity may be treated with standard reconstruction techniques, they may result in growth disturbances in younger athletes with significant growth remaining. In response to the growing need for ACL reconstruction techniques in skeletally immature individuals, physeal-sparing and physeal-respecting reconstruction techniques have been developed. In addition to the advancements in surgical technique, ACL injury prevention has also gained attention. This growing interest in ACL prevention is in part related to the high risk of ACL re-tear, either of the ACL graft or of the contralateral ACL, in children and adolescents. Recent reports indicate that well-designed neuromuscular training programs may reduce the risk of primary and subsequent ACL injuries.

Return to Sport for Skeletally Immature Athletes After ACL Reconstruction: Preventing a Second Injury Using a Quality of Movement Assessment and Quantitative Measures to Address Modifiable Risk Factors

Background:

Reinjury rates after anterior cruciate ligament reconstruction (ACLR) are highest among young athletes, who consequently suffer from low rates of return to play. Historically, quantitative measures have been used to determine readiness to return to sport; however, they do not assess modifiable risk factors related to the quality of movement.

Purpose:

To determine the effectiveness of a criteria-based rehabilitation progression and return-to-sport criteria on efficient return to activity and prevention of second injury in young athletes post-ACLR.

Study Design:

Case series; Level of evidence, 4.

Methods:

Between December 2010 and 2013, 42 skeletally immature athletes (mean chronologic age, 12 years; range, 10-15 years) who underwent ACLR using ipsilateral hamstring tendon autograft were prospectively evaluated. All athletes progressed through a criteria-based rehabilitation progression; were assessed at specific time frames for strength, biomechanical, and neuromuscular risk factors predictive of injury; and were provided targeted interventions. The final return to sport phase consisted of quantitative testing as well as a quality of movement assessment of several functional movements with progressive difficulty and sports-specific loading. Clearance for unrestricted activity was determined by achieving satisfactory results on both qualitative and quantitative assessments with consideration for the demands of each sport.

Results:

The mean time for return to unrestricted competitive activity was 12 months. All but 3 (7%) athletes returned to their primary sport. Thirty-five athletes (83%) returned to unrestricted activity. Of the 6 (14%) who sustained a second injury, 3 (50%) were injured in sports they were not cleared for. All ACL reinjuries occurred in a cutting sport. Half of reinjuries occurred within 1 year of surgery, while the remaining occurred between 1 and 2 years. Eighty-three percent of reinjuries involved highly competitive cutting athletes.

Conclusion:

In our cohort, the combination of qualitative and quantitative data served as a good indicator for reducing risk and determining readiness to return to sport.

The Relationship of the Femoral Physis and the Medial Patellofemoral Ligament in Children: A Cadaveric Study

BACKGROUND

Young athletes sustain patellar dislocations in a variety of sports. The medial patellofemoral ligament (MPFL) is a critical structure that functions as an anatomic checkrein to help prevent lateral patellar dislocation. Reconstruction of this ligament is challenging in patients with open physes because of concerns about iatrogenic damage to the femoral physis.

PURPOSE

To evaluate the relationship of the distal femoral physis and the MPFL.

STUDY DESIGN

Descriptive laboratory study.

METHODS

In 15 cadaveric, pediatric knees (age, 7-11 years), markers were placed at the proximal/distal limits of the MPFL femoral attachment and were evaluated with computed tomography. The distance from the MPFL attachment midpoint to the most medial aspect of the distal femoral physis was measured.

RESULTS

The mean femoral width of the MPFL was 8.1 mm (range, 4.3-13.8 mm). The femoral MPFL midpoint was distal to the femoral physis in 11 specimens and proximal to the physis in 4 specimens. The most proximal portion of the MPFL femoral attachment extended above the medial physis in 7, was at the physis in 5, and was below the physis in 3 specimens. One specimen had the entire MPFL femoral attachment above the physis. For knees with the MPFL midpoint above the medial physis, the distance between the center of the MPFL and physis was 3.3 mm (range, 0.3-7.1 mm). For knees with the MPFL below the medial physis, the distance between the center of the MPFL and physis was -6.8 mm (range, -0.7 to -22.0 mm).

CONCLUSION

The relationship of the femoral attachment of the MPFL and the medial femoral physis shows some anatomic variation. In all cases, the MPFL is close to the medial femoral physis, but the midpoint of the MPFL is at, slightly above, or slightly below the physis.

CLINICAL RELEVANCE

The relationship of the MPFL femoral attachment footprint to the femoral physis in the skeletally immature patient is not well understood, and access to pediatric cadaveric tissue is very limited. This small series demonstrates that there is considerable variation in the relationship between the MPFL and distal femoral physis. This anatomic information may guide MPFL reconstruction technique in young patients and reduce the risk of iatrogenic physeal arrest on the femur.

Micheli Anterior Cruciate Ligament Reconstruction in Skeletally Immature Youths: A Retrospective Case Series With a Mean 3-Year Follow-up

BACKGROUND

The management of anterior cruciate ligament (ACL) tears in the skeletally immature patient remains controversial. Outcomes on a physeal-sparing technique using the iliotibial band for combined intra-articular and extra-articular ACL reconstruction, called the Micheli technique, have been described and reported by the original authors.

PURPOSE

To evaluate the clinical outcomes of a physeal-sparing technique using the iliotibial band for combined intra-articular and extra-articular ACL reconstruction.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Between 2005 and 2011, all patients who underwent Micheli ACL reconstruction performed by a single surgeon were identified. A minimum of 3 years' growth remaining was a prerequisite for Micheli reconstruction. Patients were excluded if postoperative follow-up was less than 1 year. Patients were evaluated for functional outcomes, satisfaction, graft survival, radiographic and clinical evidence of growth disturbance, and the need for additional procedures.

RESULTS

Twenty-one patients (22 knees) met the inclusion criteria for this study. The mean age at the time of surgery was 11.8 years (range, 9.9-14.0 years). All patients were male. There were 4 concomitant meniscal repairs and 5 partial meniscectomies performed. All patients (100%) completed follow-up at a mean duration of 3.0 years (range, 1.0-6.9 years). Overall, 6 knees (27%) underwent reoperation. Of these, 3 knees (14%) underwent revision ACL surgery: 2 revision reconstructions at 2.8 and 4.0 years postoperatively and 1 graft shrinkage at 4.7 months postoperatively. Three knees (14%) underwent subsequent meniscal procedures, including 2 partial meniscectomies and 1 meniscal repair. Of the 19 knees that did not require revision ACL surgery, the median patient satisfaction score was 10 (range, 9-10). The mean Pediatric International Knee Documentation Committee score was 96.5 ± 2.9, and the mean Lysholm score was 95.0 ± 6.1. The median preinjury Tegner activity level was 8 (range, 6-10), and the median postoperative Tegner activity level was 8 (range, 6-10). Of the 19 knees that did not require revision ACL surgery, all had a normal Lachman test result, with a firm endpoint and normal pivot shift. At follow-up, 53% of knees had closed physes. There were no angular deformities or limb-length discrepancies.

CONCLUSION

At a mean 3-year follow-up, the study findings confirmed excellent functional outcomes, a low ACL revision rate, and no growth disturbances. Patients returned to their preoperative activity level after reconstruction. This procedure offers a safe and effective ACL reconstruction option in children with several years of growth remaining.

Temporary hemiarthroplasty with a synthetic device in children with osteosarcoma around the knee as a bridging procedure until skeletal maturity

BACKGROUND

We hypothesized that hemiarthroplasty with a synthetic device in skeletally immature patients with osteosarcoma around the knee would be functional due to high adaptability in the pediatric age group, and may decrease the number of surgeries until limb equalization by preserving the nearby physis.

METHODS

We analyzed the outcomes of 25 hemiarthroplasties (12 distal femur, 13 proximal tibia). Average patient age was 11.8 years. We assessed (1) whether hemiarthroplasty could be considered as a viable option and could preserve growth of the nearby physis, and (2) whether these patients could reach the final goal of adult-type tumor prosthesis implantation within a preplanned number of surgeries.

RESULTS

Three (12%) of 25 hemiarthroplasties showed failure. Average Musculoskeletal Tumor Society functional score of 23 patients was 25.1. Average tibial and femoral shortening for the corresponding reconstruction was 0.3 cm and 0.5 cm, respectively. In terms of number of surgeries for limb equalization, 19 patients (76%) had less, four (16%) had equal, and two (8%) had more surgeries than planned.

CONCLUSIONS

Hemiarthroplasty is a sound option until skeletal maturity, allowing surgeons to choose the appropriate procedure based on the patient's growth status, and may reduce the amount of shortening by preserving nearby physis.

Height, weight, and age predict quadriceps tendon length and thickness in skeletally immature patients

BACKGROUND

Quadriceps tendon autografts have been used with success in adults and are becoming a popular graft option in pediatric patients because of size, decreased donor site morbidity, ease of harvest, and favorable biomechanical characteristics. However, little is known about the length and thickness of the quadriceps tendon in pediatric patients.

PURPOSE

This study aimed to determine whether quadriceps tendon length and thickness follow a predictable pattern of development based on height, weight, age, and body mass index in skeletally immature patients.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

The height, weight, age, and sex of 151 children between 4 and 16 years old were recorded. Ultrasound measurements of the length and thickness of bilateral quadriceps tendons were performed by a single technician and recorded for statistical analysis.

RESULTS

The average quadriceps tendon length and thickness were 6.87 ± 1.49 cm and 0.37 ± 0.12 cm, respectively. Tendon length averaged 3.89 cm at age 4 years and 7.98 cm at 16 years, whereas thickness averaged 0.24 cm at 4 years and 0.40 cm at 16 years of age. There was no significant difference in tendon length or thickness between males and females (P = .97). Tendon length and thickness increased significantly with age, weight, and height (P < .01 for all).

CONCLUSION

The quadriceps tendon is of sufficient length and thickness to be used as an autograft for pediatric patients. The size of the graft is predictable using the age, height, and weight of the patient. Graft length and thickness can be easily confirmed using ultrasound.

Correlation of meniscal and articular cartilage injuries in children and adolescents with timing of anterior cruciate ligament reconstruction

BACKGROUND

In pediatric patients, anterior cruciate ligament (ACL) reconstruction is controversial; however, delaying surgery until skeletal maturity is complete may increase the risk of secondary meniscal and articular cartilage injury.

PURPOSE

To assess the risk of meniscal and chondral injuries with delay of ACL reconstruction.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Records were reviewed in patients younger than 17 years (median age, 14 years) who had ACL reconstruction. Patients were consecutively enrolled and assigned to 1 of 3 surgical groups based on timing of surgery: acute (<6 weeks after surgery), subacute (6-12 weeks), or chronic (>3 months). The type and grade of meniscal injuries was documented according to the International Society of Arthroscopy, Knee Surgery, and Orthopaedic Sports Medicine (ISAKOS) meniscal classification criteria. International Cartilage Repair Society (ICRS) criteria were used to document location and grade of chondral injuries. Associations between patient characteristics and meniscal injury were tested using rank sum and chi-square tests. Regression analyses were conducted to model incidence and severity of lateral and medial meniscal tears. There were 130 patients who had 135 ACL reconstructions between the years of 2000 and 2012.

RESULTS

Sixty-two ACL injuries were treated acutely, 37 were subacute, and 36 were chronic. Meniscal injuries (n = 112) included 70 lateral and 42 medial tears. Time to surgery had bivariate association with lateral and medial meniscal tears (P = .016 and .007, respectively). Independent risk factors for incidence of lateral meniscal tears were younger age (P = .028) and return to sports activities before surgery (P = .007). Patients with 1 episode of instability had 3-fold higher odds of higher grade lateral meniscal tear (95% CI, 1.30-7.60). Compared with acute reconstruction, subacute and chronic reconstruction patients had 1.45 and 2.82 times higher odds, respectively, of lateral meniscal tear severity (P = .12). Independent risk factors for incidence of medial meniscal tears were female sex (P = .03), older age (P = .01), and any episode of instability (P = .01). Adjusted odds ratio for medial meniscal tear was 4.7 for an instability episode (vs no episode; P = .01). Adjusted odds ratio for increased severity of medial meniscal tears included any instability episode, 5.6 (P < .01); playing sports before reconstruction, 15.2 (P < .01); and time to surgery greater than 3 months, 4.3 (P = .046). Seventeen patients had 23 chondral injuries. The risk factors for chondral injury included increased time to surgery (P = .005) and any instability episode (P = .001). For increased grade of chondral injury, risk factors were time to surgery (P ≤ .001) and any instability episode (P = .003).

CONCLUSION

Delayed ACL reconstruction increased the risks of secondary meniscal and chondral injuries in this population of pediatric patients.

All-inside, physeal-sparing anterior cruciate ligament reconstruction does not significantly compromise the physis in skeletally immature athletes: a postoperative physeal magnetic resonance imaging analysis

BACKGROUND

Anterior cruciate ligament (ACL) reconstruction in skeletally immature patients can result in growth disturbance due to iatrogenic physeal injury. Multiple physeal-sparing ACL reconstruction techniques have been described; however, few combine the benefits of anatomic reconstruction using sockets without violation of the femoral or tibial physis.

PURPOSE

To utilize physeal-specific magnetic resonance imaging (MRI) to quantify the zone of physeal injury after all-inside ACL reconstruction in skeletally immature athletes.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Twenty-three skeletally immature patients (mean chronologic age 12.6 years; range, 10-15 years) were prospectively evaluated after all-inside ACL reconstruction. The mean bone age was 13.2 years. There were 8 females and 15 males. Fifteen patients underwent an all-epiphyseal (AE) ACL reconstruction and 8 patients had a partial transphyseal (PTP) ACL reconstruction, which spared the femoral physis but crossed the tibial physis. At 6 and 12 months postoperatively, MRI using 3-dimensional fat-suppressed spoiled gradient recalled echo sequences and full-length standing radiographs were performed to assess graft survival, growth arrest, physeal violation, angular deformity, and leg length discrepancy.

RESULTS

The mean follow-up for this cohort was 18.5 months (range, 12-39 months). Minimal tibial physeal violation was seen in 10 of 15 patients in the AE group and, by definition, all patients in the PTP group. The mean area of tibial physeal disturbance (±SD) was 57.8 ± 52.2 mm(2) (mean 2.1% of total physeal area) in the AE group compared with 145.1 ± 100.6 mm(2) (mean 5.4% of total physeal area) in the PTP group (P = .003). Minimal compromise of the femoral physis (1.5%) was observed in 1 case in the PTP group and no cases in the AE group. No cases of growth arrest, articular surface violation, or avascular necrosis were noted on MRI. No postoperative angular deformities or significant leg length discrepancies were observed.

CONCLUSION

The study data suggest that all-inside ACL reconstruction is a safe technique for skeletally immature athletes at short-term follow-up. Physeal-specific MRI reveals minimal growth plate compromise that is significantly lower than published thresholds for growth arrest.

The relationship of the medial patellofemoral ligament attachment to the distal femoral physis

BACKGROUND

No published study has ever described the relationship of the medial patellofemoral ligament (MPFL) attachment to the distal femoral physis in skeletally immature cadaveric specimens. As such, there continues to be much confusion about this relationship, which is important when considering MPFL reconstruction in the skeletally immature patient.

HYPOTHESIS

The MPFL footprint is distal to the medial border of the distal femoral physis.

STUDY DESIGN

Descriptive laboratory study.

METHODS

Sixteen skeletally immature cadaveric specimens were used for this study. The average age of the specimens was 12 years (range, 10-15 years). The MPFL femoral attachment, adductor tubercle, and medial epicondyle were identified in all specimens, and the topography of the distal femoral physis was carefully described. Measurements were then taken of the distance from the medial aspect of the distal femoral physis to the MPFL femoral attachment and the horizontal distance from the MPFL femoral attachment to the point where a femoral tunnel would intersect the undulating femoral physis. All measurements were made with digital calipers.

RESULTS

The MPFL attachment was distal to the medial aspect of the femoral physis in all specimens. The MPFL attachment was an average of 8.5 mm distal to the medial aspect of the distal femoral physis. In the coronal plane, the undulating physis was 10.5 mm medial to the MPFL attachment. In all specimens, the undulations of the medial physis were concave directly posterior and lateral to the MPFL attachment and convex anterior to the MPFL attachment. Both the adductor tubercle and the medial epicondyle were also distal to the femoral physis in all specimens.

CONCLUSION

This study has confirmed the findings of others, who have shown that the MPFL femoral attachment lies distal to the medial aspect of the distal femoral physis. In addition, the study findings show that the MPFL femoral attachment is in very close proximity to the distal femoral physis.

CLINICAL RELEVANCE

To facilitate anatomic MPFL reconstruction, Schottle et al described a radiographic method to identify the MPFL femoral attachment on lateral radiographs in skeletally mature patients. Because of the complex physeal anatomy, much confusion exists concerning whether an MPFL femoral tunnel can be placed safely in the pediatric patient. The findings of this study suggest that anatomic MPFL reconstruction may be accomplished with a tunnel angled distally and anteriorly to avoid injury to the distal femoral physis.

Rotationplasty: Beauty is in the Eye of the Beholder

Rotationplasty is an alternative reconstructive strategy after sarcoma resection that often gets overlooked due to concerns about cosmesis. "Rotating" a distal segment 180 degrees and fixing it to a proximal segment leaves a highly-functional, durable reconstruction that functionally compares favorably to other limb-salvage techniques. Cosmetic outcomes have no discernible impact of the emotional and social functioning of cancer survivors following rotationplasty. This chapter discusses techniques of rotationplasty, as well as its oncologic, functional and emotional outcomes.

Prevalence and incidence of new meniscus and cartilage injuries after a nonoperative treatment algorithm for ACL tears in skeletally immature children: a prospective MRI study

BACKGROUND

The increased risk of long-term osteoarthritis from concomitant injuries to the menisci or cartilage after an anterior cruciate ligament (ACL) injury in adults is well established. In skeletally immature children, ACL reconstruction is often recommended to reduce the risk of new intra-articular injuries. However, the prevalence and incidence of new injuries after nonoperative treatment of ACL injuries in children are unknown.

PURPOSE

To prospectively investigate the incidence of new injuries to the menisci and joint cartilage in nonoperatively treated, skeletally immature children with a known ACL injury by use of bilateral 3.0-T MRI.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Forty skeletally immature children with a ruptured ACL (41 knees) followed a nonoperative treatment algorithm and were evaluated with bilateral 3.0-T MRI on 2 occasions (MRI1 and MRI2). The intra-articular structures were analyzed by 2 independent MRI radiologists. Monitoring of participation in physical activities was accomplished through a monthly online activity survey. Descriptive statistics and frequencies were extracted from the scoring forms and compared using the Fisher exact test.

RESULTS

Fourteen girls (35%) and 26 boys (65%) with a mean age of 11.0 ± 1.4 years at the time of injury were included. Time from injury to the final follow-up was 3.8 ± 1.4 years. Eighty-eight percent of the ACL-deficient children confirmed monthly participation in pivoting sports and/or in physical education classes in school. The prevalence of meniscus injuries in the 28 nonreconstructed knees was 28.5% at MRI1 and MRI2, and the incidence of new meniscus and cartilage injuries in the nonreconstructed knees from MRI1 to MRI2 was 3.6%. Thirteen children underwent ACL reconstruction, with a prevalence of meniscus procedures of 46.2%. The incidence of new meniscus injuries from diagnostic MRI to final follow-up was 19.5%. Surgical treatments for meniscus injuries were performed in 8 of the 41 knees.

CONCLUSION

The incidence of new injuries to menisci and joint cartilage was low between MRI1 and MRI2 in the 28 nonreconstructed knees. Thirty-two percent of the knees required ACL reconstruction, and 19.5% required meniscus surgeries during the 3.8 ± 1.4 years of follow-up from injury. Further follow-up is needed to evaluate the long-term knee health in these children.

Biomechanical evaluation of physeal-sparing fixation methods in tibial eminence fractures

BACKGROUND

Tibial eminence fractures occur most commonly in skeletally immature children. Several techniques using physeal-sparing fracture fixation have been described, but their structural properties have not been evaluated.

PURPOSE

To determine the strength and resistance to displacement of physeal-sparing techniques used to fix tibial eminence fractures.

STUDY DESIGN

Controlled laboratory study.

METHODS

Skeletally immature porcine knees were randomized into 4 treatment groups: (1) ultra-high molecular weight polyethylene suture-suture button (UHMWPE/SB), (2) suture anchor, (3) polydioxanone suture-suture button (PDS/SB), and (4) screw fixation. A prospective analysis of bone mineral density using dual-energy x-ray absorptiometry was performed on all specimens. Fracture fragments were created in a standardized manner and measured for size comparison. After fracture fixation, biomechanical testing was performed with cyclical and load-to-failure protocols by loading the tibia with an anterior shear force.

RESULTS

In load-to-failure testing, screw fixation had a significantly lower median peak failure load (186.4 N; lower quartile [LQ], 158.4 N; upper quartile [UQ], 232.6 N) than did UHMWPE/SB (465.8 N; LQ, 397.8 N; UQ, 527.8 N), suture anchors (440.5 N; LQ, 323.0 N; UQ, 562.3 N), and PDS/SB (404.3 N; LQ, 385.9 N; UQ, 415.6 N). UHMWPE/SB demonstrated a significantly higher median yield load (465.8 N; LQ, 397.8 N; UQ, 527.8 N) than did PDS/SB (306.7 N; LQ, 271.4, N; UQ, 405.7 N) and screw fixation (179.0 N; LQ, 120.2 N; UQ, 232.5 N). During cyclical testing, screw fixation demonstrated significantly lower percentage survival of specimens (0%) compared with the other groups (UHMWPE/SB, 100%; suture anchor, 78%; PDS/SB, 78%). After 1000 cycles of loading, PDS/SB fixation had significantly more median creep (6.76 mm; LQ, 6.34 mm; UQ, 8.28 mm) than did UHMWPE/SB (4.43 mm; LQ, 3.80 mm; UQ, 4.73 mm) and suture anchor fixation (3.06 mm; LQ, 2.59 mm; UQ, 4.28 mm). The lowest median stiffness was observed in the PDS/SB group (48.6 N/mm; LQ, 45.3 N/mm; UQ, 54.2 N/mm). UHMWPE/SB fixation demonstrated a significantly higher median peak failure load after cyclic testing (469.0 N; LQ, 380.6 N; UQ, 507.2 N) than did PDS/SB (237.7 N; LQ, 197.3 N; UQ, 298.3 N) and screw fixation (132.4 N; LQ, 123.7 N; UQ, 180.9 N). Suture anchor fixation had significantly more variance, as demonstrated by width of interquartile range, in peak failure load, yield load, and creep than did other techniques.

CONCLUSION

Physeal-sparing fixation of tibial eminence fractures with UHMWPE suture-suture button is biomechanically superior to both PDS suture-suture button and a single screw at the time of surgery and provides more consistent fixation than do suture anchors.

CLINICAL RELEVANCE

Suture anchors provide inconsistent fixation for tibial eminence fractures.

Effect of anterior cruciate healing on the uninjured ligament insertion site

The effect of anterior cruciate healing on the uninjured ligament insertion site after enhanced suture repair with collagen-platelet composites (CPC) has not yet been defined. In this study, we hypothesized that fibroblasts and osteoclasts would participate in generating histologic changes in insertion site morphology after transection and bioenhanced repair of the ACL, and that these changes would be age-dependent. Skeletally immature, adolescent, and adult Yucatan mini-pigs underwent ACL transection and bioenhanced suture repair. The histologic response to repair of the insertion site was evaluated at 1, 2, 4, and 15 weeks. In young and adolescent animals treated with bioenhanced suture repair with CPC, changes in the insertion site included: (1) fibroblastic proliferation with loss and return of collagen alignment in the fibrous zone; (2) osteoclastic resorption within fibrocartilage zones at 2-4 weeks; and (3) partial reappearance of fibrocartilage zones at 15 weeks. In adult animals; however, degenerative changes were noted by 15 weeks: (1) loss of parallel arrangement of collagen fibers in the fibrous zone; and (2) increasing disorganization and loss of columnation of chondrocytes in the fibrocartilage zone. These results suggest that fibroblasts and osteoclasts mediate histologic changes at the insertion site during bioenhanced suture repair of the ACL which may prevent insertion site degeneration, and that the magnitude of these changes may be a function of skeletal maturity.

Isolated diaphyseal fractures of the radius in skeletally immature patients

Diaphyseal radius fractures without associated ulna fracture or radioulnar dislocation (isolated fracture of the radius) are recognized in adults but are rarely described in skeletally immature patients. A search of our database (1974-2002) identified 17 pediatric patients that had an isolated fracture of the radius. Among the 13 patients with at least 1 year follow-up, ten were treated with manipulative reduction and immobilization in an above elbow cast and three had initial operative treatment with plate and screw fixation. These 13 patients were evaluated for an average of 18 months (range, 12 to 45 months) after injury using the system of Price and colleagues. The incidence of isolated diaphyseal radius fractures in skeletally immature patients was 0.56 per year in our database and represented 27% of the 63 patients with a diaphyseal forearm fracture. All 13 patients, with at least 1 year follow-up, regained full elbow flexion and extension and full forearm rotation. According to the classification system of Price, all 13 patients (100%) had an excellent result. As in adults, isolated radius fractures seem to occur in children more frequently than previously appreciated. Treatment of isolated radius fractures in skeletally immature patients has a low complication rate, and excellent functional outcomes are the rule.

Immature animals have higher cellular density in the healing anterior cruciate ligament than adolescent or adult animals

There has been recent interest in the biologic stimulation of anterior cruciate ligament (ACL) healing. However, the effect of age on the ability of ligaments to heal has not yet been defined. In this study, we hypothesized that skeletal maturity would significantly affect the cellular and vascular repopulation rate of an ACL wound site. Skeletally Immature (open physes), Adolescent (closing physes), and Adult (closed physes) Yucatan minipigs underwent bilateral ACL transection and suture repair using a collagen-platelet composite. The response to repair was evaluated histologically at 1, 2, and 4 weeks. All three groups of animals had completely populated the ACL wound site with fibroblasts at 1 week. The Immature animals had a higher cellular density in the wound site than the Adult animals at weeks 2 and 4. Cells in the Immature ligament wounds were larger and more ovoid than in the Adult wounds. There were no significant differences in the vascular density in the wound site. Animal age had a significant effect on the density of cells populating the ACL wound site. Whether this observed cellular difference has an effect on the later biomechanical function of the repaired ACL requires further study.