Osseous and Cartilaginous Trochlear Development in the Pediatric Knee: A Cadaveric Computed Tomography Study

Background

The anatomy of the trochlea plays a significant role in patellar stability. The developmental anatomy of the trochlea and its relationship to patellar stability remains poorly understood.

Purpose

To describe the developmental changes of the osseous and cartilaginous trochlear morphology in skeletally immature specimens.

Study Design

Descriptive laboratory study.

Methods

A total of 65 skeletally immature cadaveric knees between the ages of 2 months and 11 years were evaluated using computed tomography scans. The measurements in the axial plane of both cartilage and bone include medial, central, and lateral trochlear height; sulcus height; medial and later trochlear facet length; trochlear sulcus angle; patellar sulcus angle; condylar height asymmetry; and trochlear facet asymmetry. Additional measurements included trochlear depth and lateral trochlear inclination angle. In the sagittal plane, measurements included curvilinear trochlear length, direct trochlear length, condylar height, and patellar sulcus angle.

Results

Analysis of trochlear morphology using condylar height, condylar height asymmetry, and trochlear depth all increased with increasing age. The osseous and cartilaginous sulcus angles became deeper with age until age 8 and then plateaued. This corresponded with an increase in trochlear depth that also plateaued around age 8. Osseous condylar asymmetry increased with age but flipped from a larger medial condyle to a larger lateral condyle around age 8. The continued growth of the trochlea with age was further demonstrated in all measures in the sagittal view.

Conclusion

This cadaveric analysis demonstrated that there is an increase in condylar height as age increased by all measurements analyzed. These changes in condylar height continued to be seen through age 11, suggesting a still-developing trochlea past this age. By age 8, a plateau in sulcus angle, and sulcus depth suggests more proportionate growth after this point. Similar changes in trochlear and patellar shape with age suggests that the 2 structures may affect each other during development.

Clinical Relevance

This information can help design, develop, and determine timing of procedures that may alter the anatomy and stabilize the trochlear and patellofemoral joint.

Consensus-Based Guidelines for Management of First-Time Patellar Dislocation in Adolescents

BACKGROUND

The management of first-time patellar dislocation remains variable, with limited evidence to support or compare different operative and nonoperative modalities. The primary aim was to establish consensus-based guidelines for different components of nonoperative treatment following a first-time patellar dislocation. The secondary aim was to develop guidelines related to management after failed nonoperative treatment. The tertiary aim was to establish consensus-based guidelines for the management of first-time patellar dislocation with a concomitant osteochondral fracture.

METHODS

A 29-question, multiple-choice, case-based survey was developed by 20 members of the Patellofemoral Research Interest Group of the Pediatric Research in Sports Medicine Society. The survey consisted of questions related to demographic information, management of first-time patellar dislocation without an osteochondral fracture, and management of first-time patellar dislocation with a 2 cm osteochondral fracture. The survey underwent 2 rounds of iterations by Patellofemoral Research Interest Group members and the final survey was administered to Pediatric Research in Sports Medicine members, using REDCap. Consensus-based guidelines were generated when more than 66% of respondents chose the same answer.

RESULTS

Seventy-nine of 157 (50%) eligible members responded. Sixty-one were orthopaedic surgeons and 18 were primary sports medicine physicians. Eleven consensus-based guidelines were generated based on survey responses. Those that met the criteria for consensus included initial knee radiographs (99% consensus), nonoperative treatment for first-time patellar dislocation without an osteochondral fracture (99%), physical therapy starting within the first month postinjury (99%), with return to sport after 2 to 4 months (68%) with a brace (75%) and further follow-up as needed (75%). Surgical treatment was recommended if there were patellar subluxation episodes after 6 months of nonoperative treatment (84%). Patellar stabilization should be considered for a first-time dislocation with an osteochondral fracture (81.5%).

CONCLUSION

Consensus-based guidelines offer recommendations for the management of first-time patellar dislocation with or without an osteochondral fracture. Several changing trends and areas of disagreement were noted in clinical practice.

CLINICAL RELEVANCE

In the absence of high-level evidence, consensus-based guidelines may aid in clinical decision-making when treating patients following a first-time patellar dislocation. These guidelines highlight the evolving trends in clinical practice for the management of first-time patellar dislocation. Areas not reaching consensus serve as topics for future research.

MPFL Reconstruction and Implant-Mediated Guided Growth in Skeletally Immature Patients With Patellar Instability and Genu Valgum

BACKGROUND

There is a higher rate of failure of isolated MPFL reconstruction in skeletally immature patients with patellar instability compared to skeletally mature patients. Genu valgum is a known risk factor for patellar instability. There is potential for concomitant surgical correction of genu valgum to achieve better clinical outcomes and to decrease failure rates of MPFL reconstruction.

PURPOSE

To evaluate outcomes of combined medial patellofemoral ligament (MPFL) reconstruction and implant-mediated guided growth (IMGG) in skeletally immature patients with patellar instability and genu valgum.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

In a multicenter study, all skeletally immature patients with recurrent patellar instability and genu valgum who underwent MPFL reconstruction using hamstring graft and IMGG using a transphyseal screw or tension band plate for the distal femur and/or proximal tibia were included. The knee valgus angle and mechanical axis were measured on full-length radiographs and anatomic risk factors were measured on MRI. Patients were followed until correction of their lower limb alignment and implant removal or until skeletal maturity. Clinical outcomes, including complications, were analyzed.

RESULTS

A total of 31 patients (37 knees) were included in the study. The mean age and skeletal age of the cohort were 12.4 and 12.9 years, respectively. Simultaneous MPFL reconstruction and IMGG were performed in 26 of 37 knees; 11 underwent staged procedures. Twenty knees had transphyseal screws and 17 knees had tension band plates for IMGG. The knee valgus corrected from a mean of 12.4° to 5.1° in 12.1 months. Implants were removed from 22 of 37 knees once genu valgum was corrected. There was no significant difference (P = .65) in the correction rate between plates (0.7 deg/month) and screws (0.6 deg/month). Ten complications occurred in 4 patients (7 knees) and included 5 patellar redislocations, 2 rebound valgus, 1 varus overcorrection, 1 knee arthrofibrosis, and 1 implant loosening. For children <10 years of age, 3 of 6 (50%) knees had patellar redislocations and 5 of 6 knees had a complication. This was statistically significant (P = .003) compared with patients >10 years of age. Similarly, for patients with bilateral knee involvement, 5 of 12 (42%) knees had patellar redislocations and a total of 8 complications occurred in this subset. This was statistically significant (P < .001) compared with patients with unilateral involvement.

CONCLUSION

IMGG with plates or screws in the setting of combined MPFL reconstruction improves genu valgum. Children <10 years of age and those with bilateral instability with genu valgum remain difficult subsets to treat with higher complication rates.

Quadriceps tendon autograft is promising with lower graft rupture rates and better functional Lysholm scores than hamstring tendon autograft in pediatric ACL reconstruction. A systematic review and meta-analysis

Purpose

Graft rupture is the most prevalent complication following pediatric anterior cruciate ligament reconstruction (ACLR). The hamstring tendon (HT) autograft is frequently employed, while the quadriceps tendon (QT) autograft has garnered increased attention recently. This study aims to perform a systematic review to assess the complication rates and functional outcomes associated with these two widely used autografts in skeletally immature patients - comparing HT versus QT autografts.

Research question

Is QT autograft better than HT autograft for ACLR in skeletally immature cohorts?

Methodology

Three electronic databases (PubMed/Medline, Scopus, and Ovid) were comprehensively searched to identify pertinent articles reporting the outcomes of HT and QT autografts in pediatric ACLR with a minimum 2-year follow-up. Data on the outcome parameters, such as graft rupture rates, contralateral ACL injury rates, functional outcomes, and growth disturbances rates, were extracted. Meta-analysis was performed using OpenMeta Analyst software.

Results

Twelve studies were included for meta-analysis (pooled analysis) with 659 patients (QT: 205; HT: 454). The analysis showed that QT autografts had a significantly lesser graft rupture rate than HT autografts (3.5 % [95 % CI 0.2, 6.8] and 12.4 % [95 % CI 6.1, 18.7] respectively, p < 0.001). The graft rupture rates between QT with bone and without bone block showed no statistically significant difference (4.6 % [95 % CI 0.8, 1.0] and 3.5 % [95 % CI 2.0, 8.9] respectively, p = 0.181). The overall contralateral ACL injury rate was 10.2 %, and the subgroup analysis revealed no statistically significant difference between the QT and HT groups (p = 0.7). Regarding functional outcome scores at the final follow-up, the mean Lysholm score demonstrated a significant increase in the QT group compared to the HT group (p < 0.001). There were no significant differences between the two groups concerning growth disturbances at the final follow-up. Return to sports (RTS) varied between 6 and 13.5 months after surgery.

Conclusion

QT autografts demonstrate encouraging outcomes, showcasing lower graft rupture rates, better functional outcomes, and comparable contralateral ACL injury rates and growth disturbances relative to the commonly used HT autograft in skeletally immature patients undergoing ACLR.

Manipulation Under Anesthesia is Safe and Effective for Management of Early Postoperative Knee Arthrofibrosis in Adolescent Patients

BACKGROUND

Management of postoperative knee arthrofibrosis can be challenging and the preferred time for intervention remains controversial. The purpose of this study is to evaluate the safety and efficacy of early (<3 mo postoperatively) manipulation under anesthesia (MUA) for the treatment of knee arthrofibrosis in adolescent patients. We hypothesized that early MUA could restore normal knee motion with a low complication rate and without the need for more invasive intervention.

METHODS

In a retrospective review, 57 patients who underwent MUA for postoperative knee arthrofibrosis were identified. The time between the index surgery and MUA as well as changes in range of motion (ROM) before and after MUA were analyzed. Descriptive statistics with median and interquartile range were used to analyze this non-parametric study cohort. Repeated measures ANOVA was performed to assess improvement in ROM over time. A P value <0.05 denoted statistical significance.

RESULTS

The median age of the cohort at time of MUA was 14.5 years [interquartile range (IQR) 12.9 to 17.6)]. 54.4% were male. Median time to MUA was 64 days (IQR 52 to 79) after index surgery. ROM before MUA was 90.0 degrees (IQR 75 to 100), which improved to 130 degrees (120 to 135) after MUA. At final median follow-up of 8.9 months (IQR 5.1 to 16.1), mean ROM was 133 degrees (130 to 140). There were no iatrogenic fractures or physeal separations associated with MUA. 12.3% (n=7/57) failed MUA either due to the need for subsequent repeat MUA (n=2), need for lysis of adhesions (n=3) or need for surgery after MUA (n=2). Those who failed early MUA and required subsequent procedures had ROM >120 degrees at final follow-up.

CONCLUSIONS

Postoperative knee arthrofibrosis can be safely and effectively treated with early (<3 mo postoperative) MUA. There were no iatrogenic fractures or physeal separations during MUA. Patients who had recurrence of motion deficits after early MUA and required further intervention, regained satisfactory knee motion at final follow-up. Although further research is warranted to better characterize risk factors for knee arthrofibrosis in adolescent patients, early recognition and MUA is a safe and effective treatment for arthrofibrosis to help patients regain full ROM without invasive intervention.

LEVEL OF EVIDENCE

Therapeutic Study - Level IV.

Patients with bilateral patellar instability have multiple and symmetric risk factors in each knee

PURPOSE

Bilateral involvement is common in patients with patellar instability. The management of bilateral patellar instability is associated with increased complication rate. The higher complication rate in this cohort may be related to the presence of underlying anatomic risk factors. The purpose of the study was to evaluate the presence and side-to-side differences in risk factors between knees in bilateral patellar instability.

METHODS

In a retrospective study (2008-2017), demographic information, characteristics of patellar dislocation and anatomic risk factors on MRI (trochlear dysplasia, patellar height, tibial tubercle lateralization, patellar tilt, sulcus angle, bump height) were evaluated in both knees of all patients (n = 32, 15 males and 17 females) with bilateral patellar instability. The risk factors were analyzed based on established cut off values and were compared between gender, laterality and more symptomatic (index) knee. Knee symmetry and absolute differences between risk factors for both knees were analyzed.

RESULTS

The mean age of 32 patients was 14.6 ± 2.3 years. Of the 4 major anatomic risk factors, the most common were trochlear dysplasia in 59/64 (92.1%) knees and patella alta in 51/64 (79.7%) knees. Tibial tubercle lateralization was the least common risk factor being present in 8/64 (12.5%) knees. Of 64 knees, 55 (85.9%) had 2 or more risk factors and 30 (46.8%) had 3 or all 4 risk factors present. There were no significant differences in risk factors based on gender, laterality or index knee. There was symmetry between paired knees for 31/32 (96.8%) patients for trochlear depth, 29/32 (90.6%) for patellar tilt, 27/32 (84.3%) for TT-TG distance and 25/32 (78.1%) for patellar height. There were no significant differences in absolute measurements between knees for any of the risk factors.

CONCLUSION

Patients with bilateral instability had multiple risk factors, with trochlear dysplasia being the most common and increased TT-TG distance being the least common. Majority of patients had 2 or more risk factors and about half had 3 or 4 risk factors in each knee. There was symmetry between paired knees for each risk factor without any significant differences between the index knee compared to the contralateral knee.

LEVEL OF EVIDENCE

Level III.

Relationship Between Age and Pathology With Treatment of Pediatric and Adolescent Discoid Lateral Meniscus: A Report From the SCORE Multicenter Database

BACKGROUND

Surgical treatment options of discoid lateral meniscus in pediatric patients consist of saucerization with or without meniscal repair, meniscocapular stabilization, and, less often, subtotal meniscectomy.

PURPOSE

To describe a large, prospectively collected multicenter cohort of discoid menisci undergoing surgical intervention, and further investigate corresponding treatment of discoid menisci.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

A multicenter quality improvement registry (16 institutions, 26 surgeons), Sports Cohort Outcomes Registry, was queried. Patient characteristics, discoid type, presence and type of intrasubstance meniscal tear, peripheral rim instability, repair technique, and partial meniscectomy/debridement beyond saucerization were reviewed. Discoid meniscus characteristics were compared between age groups (<14 and >14 years old), based on receiver operating characteristic curve, and discoid morphology (complete and incomplete).

RESULTS

In total, 274 patients were identified (mean age, 12.4 years; range, 3-18 years), of whom 55.6% had complete discoid. Meniscal repairs were performed in 55.1% of patients. Overall, 48.5% of patients had rim instability and 36.8% had >1 location of peripheral rim instability. Of the patients, 21.5% underwent meniscal debridement beyond saucerization, with 8.4% undergoing a subtotal meniscectomy. Patients <14 years of age were more likely to have a complete discoid meniscus (P < .001), peripheral rim instability (P = .005), and longitudinal tears (P = .015) and require a meniscal repair (P < .001). Patients ≥14 years of age were more likely to have a radial/oblique tear (P = .015) and require additional debridement beyond the physiologic rim (P = .003). Overall, 70% of patients <14 years of age were found to have a complete discoid meniscus necessitating saucerization, and >50% in this young age group required peripheral stabilization/repair.

CONCLUSION

To preserve physiological "normal" meniscus, a repair may be indicated in >50% of patients <14 years of age but occurred in <50% of those >14 years. Additional resection beyond the physiological rim may be needed in 15% of younger patients and 30% of those aged >14 years.

Intrarater and Interrater Reliability of Radiographic Characteristics in Skeletally Immature Patients With Anterior Cruciate Ligament Tears: A PLUTO Study Group Reliability Study

BACKGROUND

Radiographic measurements of limb alignment in skeletally immature patients with anterior cruciate ligament (ACL) tears are frequently used for surgical decision-making, preoperative planning, and postoperative monitoring of skeletal growth. However, the interrater and intrarater reliability of these radiographic characteristics in this patient population is not well documented.

HYPOTHESIS

Excellent reliability across 4 raters will be demonstrated for all digital measures of length, coronal plane joint orientation angles, mechanical axis, and tibial slope in skeletally immature patients with ACL tears.

STUDY DESIGN

Cohort study (diagnosis).

METHODS

Three fellowship-trained orthopaedic surgeons and 1 medical student performed 2 rounds of radiographic measurements on digital imaging (lateral knee radiographs and long-leg radiographs) of skeletally immature patients with ACL tears. Intrarater and interrater reliability for continuous radiographic measurements was assessed with intraclass correlation coefficients (ICCs) across 4 raters with 95% CIs for affected and unaffected side measurements. Interrater reliability analysis used an ICC (2, 4) structure and intrarater reliability analysis used an ICC (2, 1) structure. A weighted kappa coefficient was calculated for ordinal variables along with 95% CIs for both interrater and intrarater reliability. Agreement statistic interpretations are based on scales described by Fleiss, and Cicchetti and Sparrow: <0.40, poor; 0.40 to 0.59, fair; 0.60 to 0.74, good; and >0.74, excellent.

RESULTS

Radiographs from a convenience sample of 43 patients were included. Intrarater reliability was excellent for nearly all measurements and raters. Interrater reliability was also excellent for nearly all reads for all measurements.

CONCLUSION

Radiographic reliability of long-leg radiographs and lateral knee x-rays in skeletally immature children with ACL tears is excellent across nearly all measures and raters and can be obtained and interpreted as reliable and reproducible means to measure limb length and alignment.

LEVEL OF EVIDENCE

Level III.

4-in-1 Quadricepsplasty for Habitual and Fixed Lateral Patellar Dislocation in Children

BACKGROUND

Habitual and fixed patellar dislocations represent extreme forms of patellar instability and can lead to significant functional loss. The underlying complex pathoanatomy of a laterally positioned and shortened extensor mechanism poses challenges in its management. The purpose of our study was to evaluate the anatomic risk factors and outcomes of a 4-in-1 quadricepsplasty (wide lateral releases, Insall proximal tube realignment, Roux-Goldthwait patellar tendon hemi-transfer, and step-wise quadriceps lengthening) for stabilization of habitual and fixed patellar dislocation.

METHODS

In a retrospective study, all patients with habitual and fixed patellar dislocation who underwent 4-in-1 quadricepsplasty and had a minimum 2-year follow-up were identified. Preoperative magnetic resonance imagings were evaluated for the presence of anatomic risk factors. As a prospective part of the study, patient-reported outcomes were collected using validated instruments including Pedi-IKDC, HSS-Pedi FABS activity score, BPII 2.0 score, Kujala score, and KOOS score.

RESULTS

Seventeen knees (12 patients) formed the study cohort. Twelve knees had habitual dislocation (9 in extension and 4 in flexion) and 5 had fixed dislocation. Mean age was 9 years. 6/17 (35.3%) knees were associated with syndromes. On magnetic resonance imaging, trochlear dysplasia was the most common anatomic risk factor present in 15/17 (88.2%) knees. 13/17 (76%) knees had presence of 2 or more risk factors. At the mean follow-up of 43.3 months, the mean Pedi-IKDC score was 88.1, the HSS-Pedi FABS activity score was 15.6, the BPII 2.0 score was 78.2, the Kujala score was 90, KOOS score was 93.9, and overall patient satisfaction score was 83.3. For complications, 3/17 knees (17.6%) had recurrent patellar instability, 1 knee had postoperative stiffness that required manipulation under anesthesia and 1 knee had a superficial wound infection.

CONCLUSIONS

Most patients with habitual and fixed patellar dislocation present during the first decade of life. There are several underlying anatomic risk factors, the most common being trochlear dysplasia and patellar tilt. The 4-in-1 quadricepsplasty technique provides reliable patellar stabilization, satisfactory clinical results, and acceptable patient-reported outcomes at a minimum 2-year follow-up, with a 17.6% redislocation rate.

LEVEL OF EVIDENCE

Level IV.

Evaluation of the Optimal Femoral Fixation Site for Medial Patellofemoral Ligament Reconstruction in the Skeletally Immature Patient

The aim of this study was to assess which femoral fixation site, distal to the physis, most closely emulates the native medial patellofemoral ligament (nMPFL) length relationship in the pediatric knee. Lateral knee radiographs were taken incrementally, from 0° to 120° of flexion. The femoral origin of the nMPFL and 3 other MPFL femoral fixation sites distal to the physis were identified (P1, 1 cm distal to physis along the posterior femoral cortex; P2, 2 cm distal to physis along the posterior femoral cortex; P3, 1 cm distal and 1 cm anterior). Virtual MPFL lengths were measured from all sites. Measurement reliability was assessed using intraclass correlation coefficients. Primary comparison between simulated MPFL length at native and femoral fixation sites was made using a repeated measures analysis of variance at 30° flexion. Bivariate Pearson correlation was used to assess the relationship between fixation sites and nMPFL through the range of motion (alpha=0.05). The intra-class correlation coefficient for intraobserver reliability of MPFL length measurement was excellent. Analysis of variance showed virtual MPFL lengths from proposed femoral fixation sites at 30° were significantly different from nMPFL length (P<.01). The P1 MPFL had the least difference in means compared with nMPFL (-2.6±1.8 mm). Correlational analysis showed that P1 MPFL had the closest relationship with nMPFL compared with other femoral fixation sites (R=0.91, P<.01). The P1 MPFL had the length change most comparable to that of nMPFL (23.9±3.1 mm vs 13.3±2.85 mm) compared with the other simulated MPFLs. Femoral graft fixation site 1 cm distal to the physis in the lateral view along the posterior femoral cortex closely represents the length relationship of the nMPFL. [Orthopedics. 2023;46(2):108-113.].

Comparative Effectiveness of Nonoperative Versus Operative Treatment of Completely Displaced Clavicle Shaft Fractures Among Children

The goal of this study was to compare outcomes among children treated nonoperatively vs operatively for completely displaced clavicle fractures. This was a retrospective cohort study of nonoperative vs operative treatment of completely displaced clavicle fractures sustained between 2006 and 2015 among pediatric patients. Data were collected on patient demographics, fracture characteristics, time to return to full activities, treatment complications, and patient-reported outcome measures. Fifty-five patients were identified in the nonoperative group, with a mean age of 11.6 years (range, 8-14 years). The operative group contained 55 patients, with a mean age of 14.3 years (range, 9-17 years). All fractures healed, with a mean time to return to full activities of 90.4 days in the nonoperative group and 89.7 days in the operative group (P=.941). Twelve (22%) nonoperative patients sustained a refracture of their clavicle compared with 4 patients in the operative group (P=.031). Fifteen patients (27%) in the operative group required a second surgery for removal of surgical implants. On the shortened form of the Disabilities of the Arm, Shoulder and Hand (QuickDASH) survey, 17 of the 22 nonoperative patients reported a score of zero (indicating no disability) (range, 0-7) vs 22 of 25 in the operative group (range, 0-9) (P=.329). Patients treated nonoperatively had a 22% rate of refracture, whereas patients treated operatively had a 27% rate of undergoing a second surgery for removal of surgical implants. These data can aid in the shared decision-making process with patients and families when deciding on treatment for displaced pediatric clavicle fractures. [Orthopedics. 2022;45(6):373-377.].

Medial clavicle shaft fractures in children and adolescents: differences from adults and management

Clavicle fractures are a common injury in the pediatric and adolescent population. Most fractures are located in the middle third of the clavicle. There has been no information in the literature regarding the management of extra-physeal medial clavicle shaft fractures in this population. The objective of this study is to evaluate demographic and injury characteristics, management options and clinical outcomes of medial clavicle fractures in children and adolescents and differentiate them from those in adults. A retrospective review was performed at a single institution to identify patients with medial clavicle shaft fractures. Radiographs, clinical features and patient-reported outcomes (QuickDASH) were analyzed. Eight patients were identified with medial clavicle fractures. Two fractures could not be diagnosed on anteroposterior radiographs. Both operative (four patients) and nonoperative (four patients) treatment had excellent radiographic and clinical outcomes, irrespective of initial displacement. Compared to high-energy and life-threatening injuries in adults, these fractures in children and adolescents were sports-related and isolated fractures. Conservative treatment should be considered for medial clavicle fractures in children and adolescents. These fractures are distinct from their adult counterparts and do not lead to increased morbidity or mortality.

Many Radiographic and Magnetic Resonance Imaging Assessments for Surgical Decision Making in Pediatric Patellofemoral Instability Patients Demonstrate Poor Interrater Reliability

PURPOSE

To evaluate the interrater reliability of several common radiologic parameters used for patellofemoral instability and to attempt to improve reliability for measurements demonstrating unacceptable interrater reliability through consensus training.

METHODS

Fifty patients with patellar instability between the ages of 10 and 19 years were selected from a prospectively enrolled cohort. For measurements demonstrating unacceptable interrater reliability (intraclass correlation coefficient [ICC]: <0.6), raters discussed consensus methods to improve reliability and re-examined a subset of 20 images from the previous set of images. If reliability was still low after the second round of assessment, the measure was considered unreliable.

RESULTS

Of the 50 included subjects, 22 (44%) were male and the mean age at the time of imaging was 14 ± 2 years. With 1 or fewer consensus training sessions, the interrater reliability of the following radiograph indices were found to be reliable: trochlea crossing sign (ICC: 0.625), congruence angle (ICC: 0.768), Caton-Deshamps index (ICC: 0.644), lateral patellofemoral angle (ICC: 0.768), and mechanical axis deviation on hip-to-ankle alignment radiographs (ICC: 0.665-0.777). Reliable magnetic resonance imaging (MRI) indices were trochlear depth (ICC: 0.743), trochlear bump (ICC: 0.861), sulcus angle (ICC: 0.684), patellar tilt (ICC: 0.841), tibial tubercle to trochlear groove distance (ICC: 0.706), effusion (ICC: 0.866), and bone marrow edema (ICC: 0.961).

CONCLUSIONS

With 1 or fewer consensus training sessions, the interrater reliability of the following patellofemoral indices were found to be reliable for trochlear morphology: trochlea crossing sign and congruence angle on radiograph and trochlear depth, trochlear bump, and sulcus angle on MRI. Reliable patellar position measurements included: Caton-Deshamps index and lateral patellofemoral angle on radiograph and patellar tilt and tibial tubercle to trochlear groove distance on MRI. Additional global measurements (e.g., mechanical axis deviation on standing radiographs) and MRI assessments demonstrated acceptable reliability.

LEVEL OF EVIDENCE

II, prospective diagnostic study.

Nonunion of the Clavicle Among Children: A Review of the Literature and a Report of Three New Cases

Nonunion of the clavicle among children and adolescents is rare. A systematic review was conducted to identify published reports of nonunion of the clavicle among children after conservative treatment. A retrospective study was performed of 2096 children who were treated for clavicle fractures at our institution to identify cases of nonunion. Fourteen studies (27 children) from the literature met the inclusion criteria, and 3 new cases from our institution were identified. The mean age at injury was 11 years. Male sex, age younger than 12 years at the time of injury, and refracture of the clavicle are possible predisposing factors for nonunion. [Orthopedics. 2022;45(4):e190-e195.].

The Holstein-Lewis humerus shaft fracture in children: are they different from adults?

Spiral fractures in the distal third humerus shaft (Holstein-Lewis fracture pattern) have been associated with high risk of radial nerve palsy in adults and surgical treatment is recommended as the treatment of choice to remove the entrapped nerve from the fracture site. But this association and treatment approach has not been evaluated in pediatric humerus shaft fractures. In a retrospective study, 38 pediatric patients with Holstein-Lewis fracture configuration were identified after a review of radiographs of 1609 patients with humerus shaft fracture. Age at initial presentation, sex, mechanism of injury, side involved, presence of any associated injuries, neurovascular status, radial nerve status, fracture management, and any complications were noted. Thiry-three (86.8%) patients with mean age 10.1 ± 3.7 years were successfully treated by closed methods. Five patients (13.2%) with mean age 15.2 ± 2.6 years underwent surgical treatment. Contrary to adults, no children/adolescents had radial nerve palsy at presentation. Radiographic healing was acceptable in all cases at latest follow-up. Holstein-Lewis fracture behaves differently in children with no increased risk of radial nerve palsy. Majority can be treated conservatively. The thick periosteum in children may offer protection to the radial nerve and may be responsible for the success of closed treatment.

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).

4-in-1 Quadricepsplasty for Fixed and Habitual Dislocation of Patella

Fixed and habitual dislocations of patella represent the most severe forms of patellar instability and frequently require surgical intervention. Isolated medial patellofemoral ligament (MPFL) reconstruction, which has been the cornerstone of treatment for episodic patellar dislocation, is inadequate to address such complex instability patterns. The purpose of this report is to describe the 4-in-1 quadricepsplasty technique for stabilization of fixed and habitual dislocation of patella. The 4 components of quadricepsplasty are lateral retinacular releases and lengthening, Roux-Goldthwait patellar tendon hemi-transfer, modified Insall's proximal "tube" realignment, and quadriceps slide-lengthening.

Early Operative Versus Delayed Operative Versus Nonoperative Treatment of Pediatric and Adolescent Anterior Cruciate Ligament Injuries: A Systematic Review and Meta-analysis

BACKGROUND

Treatment options for pediatric and adolescent anterior cruciate ligament (ACL) injuries include early operative, delayed operative, and nonoperative management. Currently, there is a lack of consensus regarding the optimal treatment for these injuries.

PURPOSE/HYPOTHESIS

The purpose was to determine the optimal treatment strategy for ACL injuries in pediatric and adolescent patients. We hypothesized that (1) early ACL reconstruction results in fewer meniscal tears than delayed reconstruction but yields no difference in knee stability and (2) when compared with nonoperative management, any operative management results in fewer meniscal tears and cartilage injuries, greater knee stability, and higher return-to-sport rates.

STUDY DESIGN

Systematic review and meta-analysis; Level of evidence, 4.

METHODS

A systematic search of databases was performed including PubMed, Embase, and Cochrane Library using PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Inclusion criteria were a pediatric and adolescent patient population (≤19 years old at surgery), the reporting of clinical outcomes after treatment of primary ACL injury, and original scientific research article. Exclusion criteria were revision ACL reconstruction, tibial spine avulsion fracture, case report or small case series (<5 patients), non-English language manuscripts, multiligamentous injuries, and nonclinical studies.

RESULTS

A total of 30 studies containing 50 cohorts and representing 1176 patients met our criteria. With respect to nonoperative treatment, knee instability was observed in 20% to 100%, and return to preinjury level of sports ranged from 6% to 50% at final follow-up. Regarding operative treatment, meta-analysis results favored early ACL reconstruction over delayed reconstruction (>12 weeks) for the presence of any meniscal tear (odds ratio, 0.23; P = .006) and irreparable meniscal tear (odds ratio, 0.31; P = .001). Comparison of any side-to-side differences in KT-1000 arthrometer testing did not favor early or delayed ACL reconstruction in either continuous mean differences (P = .413) or proportion with difference ≥3 mm (P = .181). Return to preinjury level of competition rates for early and delayed ACL reconstruction ranged from 57% to 100%.

CONCLUSION

Delaying ACL reconstruction in pediatric or adolescent patients for >12 weeks significantly increased the risk of meniscal injuries and irreparable meniscal tears; however, early and delayed operative treatment achieved satisfactory knee stability. Nonoperative management resulted in high rates of residual knee instability, increased risk of meniscal tears, and comparatively low rates of return to sports.

Reliability of Radiologic Assessments of Clinically Relevant Growth Remaining in Knee MRI of Children and Adolescents With Patellofemoral Instability: Data From the JUPITER Cohort

Background

Surgical decision making and preoperative planning for children and adolescents with patellofemoral instability rely heavily on a patient's skeletal maturity. To be clinically useful, radiologic assessments of skeletal maturity must demonstrate acceptable interrater reliability and accuracy.

Purpose

The purpose of this study was to examine the interrater reliability among surgeons of varying experience levels and specialty training backgrounds when evaluating the skeletal maturity of the distal femur and proximal tibia of children and adolescents with patellofemoral instability.

Study Design

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

Methods

Six fellowship-trained orthopaedic surgeons (3 pediatric orthopaedic, 2 sports medicine, and 1 with both) who perform a high volume of patellofemoral instability surgery examined 20 blinded knee radiographs and magnetic resonance images in random order. They assessed these images for clinically relevant growth (open physis) or clinically insignificant growth (closing/closed physis) remaining in the distal femoral and proximal tibial physes. Fleiss' kappa was calculated for each measurement. After initial ratings, raters discussed consensus methods to improve reliability and assessed the images again to determine if training and new criteria improved interrater reliability.

Results

Reliability for initial assessments of distal femoral and proximal tibial physeal patency was poor (kappa range, 0.01-0.58). After consensus building, all assessments demonstrated almost-perfect interrater reliability (kappa, 0.99 for all measurements).

Conclusion

Surgical decision making and preoperative planning for children and adolescents with patellofemoral instability rely heavily on radiologic assessment of skeletal maturity. This study found that initial interrater reliability of physeal patency and clinical decision making was unacceptably low. However, with the addition of new criteria, a consensus-building process, and training, these variables became highly reliable.

Noniatrogenic Medial Patellar Dislocations: Case Series and International Patellofemoral Study Group Experience

Background:

Most patellar dislocations occur in a lateral direction because of a summed lateral force vector and predisposing anatomic risk factors. Medial patellar instability is rare and is a well-recognized iatrogenic complication of an overly aggressive lateral retinacular release. Noniatrogenic medial patellar dislocations are rare. The management of these injuries is not well described.

Purpose:

To describe the experience of the International Patellofemoral Study Group with patients with noniatrogenic medial patellar dislocation.

Study Design:

Case series; Level of evidence, 4.

Methods:

Members of the International Patellofemoral Study Group (N = 64) were surveyed between October 2018 and April 2019. This group was chosen because of its wide referral base and interest in patellar instability. Specialists who had encountered a patient with medial patellar instability were sent a questionnaire inquiring about details of the case, including patient demographics, medical history, level of athletic competition, injury characteristics, and treatment. Cases were confirmed by physical examination records and, in some cases, with findings on advanced radiographic imaging.

Results:

The survey response rate was 73% (47/64). Three of the 47 specialists (6.4%) reported they had seen a case of noniatrogenic medial patellar dislocation, for a total of 6 cases. Four cases were described as recurrent medial dislocations in the setting of hypermobile Ehlers-Danlos syndrome; 2 were treated nonoperatively, 1 underwent lateral patellofemoral ligament reconstruction, and 1 underwent derotational osteotomies. Two medial-sided patellar dislocations in collegiate athletes were sports-related injuries that required surgical debridement but no ligamentous reconstruction. None of the patients had persistent or recurrent instability at the time of their most recent follow-up.

Conclusion:

Noniatrogenic medial patellar dislocations are extremely rare. This case review suggests that the treatment of first-time medial patellar instability in patients without known risk factors should follow the same principles as the treatment of lateral instability with no known risk factors, which is nonoperative management. For patients with documented risk factors and recurrence, surgery to address the risk factors may be appropriate.

What's New in Osteochondritis Dissecans of the Knee, Elbow, and Ankle

Osteochondritis dissecans is a condition of the subchondral bone, with secondary effects on the articular cartilage. It most commonly affects the knee, elbow, and ankle and is typically seen in young, active populations. Many osteochondritis dissecans lesions are asymptomatic, but more advanced lesions can cause pain, swelling, and mechanical symptoms. Multiple treatment options have been proposed, including nonsurgical and surgical approaches. It is important to be aware of the epidemiology, presenting symptoms, and indications for nonsurgical and surgical treatment options for osteochondritis dissecans of the knee, elbow, and ankle.

What's New in the Management of Pediatric Anterior Cruciate Ligament Tears and Tibial Spine Fractures

As the number of pediatric and adolescent patients participating in sports continues to increase, so too does the incidence of anterior cruciate ligament (ACL) tears in this population. There is increasing research on pediatric and adolescent ACL tears; hundreds of articles on the topic have been published in the past few years alone. It is important to highlight the most pertinent information in the past decade. In discussing pediatric ACL tears, it is also important to review tibial spine fractures. These injuries are rightfully grouped together because tibial spine fractures often occur with a mechanism of injury similar to that of ACL tears, but typically in a younger age group. Because management is different, understanding the similarities and differences between the two pathologies is important. Recent updates on the epidemiology, diagnosis, management, and outcomes of both pediatric ACL tears and tibial spine fractures need to be reviewed.

Medial Patellofemoral Ligament Reconstruction With Growth Modulation in Children With Patellar Instability and Genu Valgum

Patellar instability is common in the second decade, and genu valgum is a risk factor for patellar instability. In skeletally immature patients, genu valgum can be gradually corrected using less-invasive, well-established, growth-modulation techniques. For skeletally immature patients with patellar instability and genu valgum, it would be desirable to address both instability and deformity. We describe our technique of physeal-respecting medial patellofemoral ligament reconstruction in skeletally immature patients using hamstring autograft and simultaneous transphyseal screw hemiepiphysiodesis to gradually correct genu valgum. The medial patellofemoral ligament reconstruction technique features posteromedial hamstring graft harvest, single patellar tunnel fixation without implant, and femoral attachment just below the distal femoral physis. The technique of growth modulation features percutaneous insertion of a single transphyseal screw through the distal medial femoral physis without interference with medial patellofemoral ligament graft placement. Our preliminary results have been encouraging with successful correction of genu valgum and satisfactory patellar stabilization without growth disturbances.

Anterior Cruciate Ligament Injury Risk in Sport: A Systematic Review and Meta-Analysis of Injury Incidence by Sex and Sport Classification

OBJECTIVE

To evaluate sex differences in incidence rates (IRs) of anterior cruciate ligament (ACL) injury by sport type (collision, contact, limited contact, and noncontact).

DATA SOURCES

A systematic review was performed using the electronic databases PubMed (1969-January 20, 2017) and EBSCOhost (CINAHL, SPORTDiscus; 1969-January 20, 2017) and the search terms anterior cruciate ligament AND injury AND (incidence OR prevalence OR epidemiology).

STUDY SELECTION

Studies were included if they provided the number of ACL injuries and the number of athlete-exposures (AEs) by sex or enough information to allow the number of ACL injuries by sex to be calculated. Studies were excluded if they were analyses of previously reported data or were not written in English.

DATA EXTRACTION

Data on sport classification, number of ACL injuries by sex, person-time in AEs for each sex, year of publication, sport, sport type, and level of play were extracted for analysis.

DATA SYNTHESIS

We conducted IR and IR ratio (IRR) meta-analyses, weighted for study size and calculated. Female and male athletes had similar ACL injury IRs for the following sport types: collision (2.10/10 000 versus 1.12/10 000 AEs, IRR = 1.14, P = .63), limited contact (0.71/10 000 versus 0.29/10 000 AEs, IRR = 1.21, P = .77), and noncontact (0.36/10 000 versus 0.21/10 000 AEs, IRR = 1.49, P = .22) sports. For contact sports, female athletes had a greater risk of injury than male athletes did (1.88/10 000 versus 0.87/10 000 AEs, IRR = 3.00, P < .001). Gymnastics and obstacle-course races were outliers with respect to IR, so we created a sport category of fixed-object, high-impact rotational landing (HIRL). For this sport type, female athletes had a greater risk of ACL injury than male athletes did (4.80/10 000 versus 1.75/10 000 AEs, IRR = 5.51, P < .001), and the overall IRs of ACL injury were greater than all IRs in all other sport categories.

CONCLUSIONS

Fixed-object HIRL sports had the highest IRs of ACL injury for both sexes. Female athletes were at greater risk of ACL injury than male athletes in contact and fixed-object HIRL sports.

Biomechanical and Functional Outcomes After Medial Patellofemoral Ligament Reconstruction: A Pilot Study

Background:

Previous studies have acknowledged the medial patellofemoral ligament (MPFL) as the primary stabilizer of the patella, preventing lateral displacement. MPFL reconstruction (MPFL-R) restores stability and functionality to the patellofemoral joint and has emerged as a preferred treatment option for recurrent lateral patellar instability.

Purpose:

To objectively measure biomechanical characteristics of athletes cleared for return to sport after MPFL-R compared with healthy controls.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

A prospective case-control study design was employed on 31 total athletes. Sixteen athletes (6 male, 10 female; mean age, 16.1 ± 2.74 years; 385 ± 189 days after surgery and 235 ± 157 days after return to sport) underwent MPFL-R and were medically cleared to return to sport. This group was matched by age, sex, and activity level to 15 healthy athletes with no history of lower extremity injuries. Athletes and controls completed validated questionnaires as well as hopping, jumping, and cutting tests with 3-dimensional motion analysis and underwent strength, flexibility, laxity, and balance assessments.

Results:

Participants in the MPFL-R group scored significantly lower (worse) on the International Knee Documentation Committee (IKDC) (89.2 ± 7.6 vs 98.1 ± 2.0, respectively; P = .0005) and significantly higher (worse) on the Tampa Scale for Kinesiophobia (TSK) (32.4 ± 5.0 vs 25.4 ± 6.5, respectively; P = .006) than those in the control group, but there was no difference in the Kujala score (95.6 ± 5.3 vs 98.8 ± 3.0, respectively; P = .06). Participants in the MPFL-R group demonstrated reduced hip and ankle flexion relative to those in the control group (P < .05). Participants in the MPFL-R group also took significantly longer to complete the 6-m timed hop test relative to those in the control group (P < .05). No statistically significant differences were found in anthropometrics, knee extension or flexion strength, hamstring flexibility, hip abduction strength, or joint laxity between the MPFL-R and control groups.

Conclusion:

The current data indicate that MPFL-R generally restores functional symmetry, while subtle deficits in global power may remain after being released to full activity. Clinicians should ensure that athletes are fully rehabilitated before returning to sport after MPFL-R by emphasizing functional multijoint exercises.

Special Considerations for Pediatric Patellar Instability

Patellar instability in children and adolescents is a challenging subset to treat. Varied forms of instability, ranging from episodic dislocation to fixed dislocation, have been recognized. It is of utmost importance for the treating physician to recognize these different patterns of instability and their associated risk factors, as more complex patterns of instability would require more extensive surgical procedures. Medial patellofemoral ligament (MPFL) reconstruction, by itself, may not suffice or may not be appropriate for the more complex instability patterns. Appropriate and early treatment of such instability in children would allow for functional progression and possible remodeling of the trochlea. However, early treatment has the associated risk of growth disturbances when surgical procedures are performed around open physis or if adult-type bony procedures are performed in children. Recent knowledge about the relationship between trochlea, MPFL femoral attachment, and distal femoral physis could help to advance safe surgical care for these patients. This article reviews the pathophysiology, risk factors, and the existing classification systems for patellar instability in children and adolescents. It focuses on varied surgical techniques, which are unique to the pediatric population, and summarizes the outcomes of these surgical techniques.

A Rare Presentation and Management of Forearm Deformity in a Patient with Hereditary Multiple Exostoses: A Case Report

CASE

We report the case of a patient with a long-standing and progressive forearm deformity, secondary to underlying hereditary multiple exostoses (HME). A salvage surgery was performed with excision of the pathologic parts of the radius and the ulna, followed by the creation of a 1-bone forearm.

CONCLUSION

One of the common manifestations of HME is forearm deformity due to abnormal ossification and osteochondromas that affect the radius and/or the ulna. Progressive deformity can lead to increasing pain, joint instability, limited motion, and functional decline. Neglected or recalcitrant deformities pose a treatment challenge. At 1.5 years after surgery, the patient had a satisfactory outcome with a fully functional, pain-free forearm in a fixed, neutral position.

Predicting Risk of Recurrent Patellar Dislocation

PURPOSE OF REVIEW

Lateral patellar dislocation (LPD) is one of the most common injuries of the knee, especially in a young patient. It is multifactorial with several underlying risk factors. The purpose of this review is to present the most recent data concerning risk factors and their predictive value to estimate recurrent LPD risk.

RECENT FINDINGS

Several demographic risk factors (age, skeletal immaturity, sex, bilaterality), mechanism of injury, and anatomic risk factors (trochlear dysplasia, patella alta, excessive tibial tubercle lateralization, increased patellar tilt) have been recognized. The combination of different risk factors, their relative contribution to instability, weightage of each factor, and multivariate analysis have led to the development of a prediction model and instability scoring system. If recurrent instability and poor outcomes could be predicted based on these prediction tools, then alternative treatment or early surgical intervention after first-time LPD could be considered. This information can also be used to predict contralateral LPD and failure of surgical treatment. Current prediction tools are mainly based on retrospective studies. In the future, prospective validation of these prognostic factors would be beneficial.

Skeletally Immature Anterior Cruciate Ligament Injuries: Controversies and Management

At one time, anterior cruciate ligament (ACL) tears in skeletally immature patients were considered rare. The recommended treatment option for skeletally immature patients with ACL tears was to modify activities until skeletal maturity, at which point definitive ACL reconstruction could be safely performed. The management of ACL tears in skeletally immature patients has evolved as a result of the increased frequency of ACL tears in younger patients and an increased awareness for the potential development or worsening of meniscal tears, chondral lesions, and degenerative changes that occur with the "wait-and-fix-later" approach. The surgical options for ACL reconstruction in skeletally immature patients include physeal-sparing, partial transphyseal, and complete transphyseal techniques. The timing and ideal technique for ACL reconstruction in skeletally immature patients are controversial. Accurate assessment of skeletal growth remaining and concerns for iatrogenic growth disturbances continually challenge treating physicians. Similar controversies with regard to the treatment of skeletally immature patients who have partial ACL tears or congenital absence of the ACL also exist.

Predictors of Recurrent Patellar Instability in Children and Adolescents After First-time Dislocation

BACKGROUND

Patellar dislocations are one of the most common knee injuries in children and adolescents and are challenging to treat. Recurrence rates are relatively high and many patients have functional limitations, even in the absence of a recurrent instability episode. The purpose of this study was to examine the risk factors in patients with first-time patellofemoral dislocations to develop a prediction model of recurrence.

METHODS

A single institution retrospective review of all patients with a first-time patellofemoral dislocation from 2002 to 2013 was performed. Demographic risk factors (age, sex, laterality, mechanism of injury, and history of contralateral patellar dislocation) and radiographic risk factors (increased patella height, trochlear dysplasia, and skeletal immaturity) were examined. Patella height was measured using Caton-Deschamps index (CDI). Trochlear dysplasia was assessed using the 2-grade Dejour classification and skeletal immaturity was assessed based on the distal femur and proximal tibia physis (open, closing, or closed).

RESULTS

In total, 266 knees in 250 patients were included in the study. Of these, 222 (83.5%) were treated nonoperatively and 44 (16.5%) were treated surgically. Of the knees treated nonoperatively, 77 (34.7%) had a recurrence. Significant risk factors for recurrence on univariate analysis were age 14 years and below, history of contralateral patellar dislocation, trochlear dysplasia, skeletal immaturity, and a CDI>1.45. Multivariate analysis was performed and trochlear dysplasia and skeletal immaturity were the most significant factors with odds ratios of 3.56 and 2.23, respectively. The presence of all 4 multivariate risk factors (CDI>1.45, history of contralateral patellar dislocation, trochlear dysplasia, and skeletal immaturity) had a predicted risk of recurrence of 88%. The presence of any 3 risk factors had a predicted risk of about 75% and the presence of any 2 risk factors had a predicted risk of about 55%.

CONCLUSIONS

Trochlear dysplasia, skeletal immaturity, CDI>1.45, and a history of contralateral patellar dislocation were all significant risk factors for recurrence in patients with first-time patellar dislocations. A predictive model for calculation of recurrence risk was developed for any combination of the different risk factors. This information is useful when counseling patients and their families after first-time patellar dislocation about prognosis and potential outcomes.

LEVEL OF EVIDENCE

Level IV-retrospective case series.

Outcomes After Isolated Medial Patellofemoral Ligament Reconstruction for the Treatment of Recurrent Lateral Patellar Dislocations: A Systematic Review and Meta-analysis

BACKGROUND

A patellar dislocation is a common knee injury in the young, athletic patient population. Recent trends indicate that the use of long-term nonoperative treatment is decreasing, and surgical intervention is more commonly recommended for those patients who fail initial nonoperative management with recurrent patellar dislocations. Medial patellofemoral ligament (MPFL) reconstruction has become increasingly utilized in this regard.

PURPOSE

To evaluate outcomes, particularly return to sports and its relationship to postoperative instability, of isolated MPFL reconstruction for the treatment of recurrent patellar dislocations.

STUDY DESIGN

Systematic review and meta-analysis.

METHODS

A review of the current literature was performed using the terms "medial patellofemoral ligament reconstruction" and "MPFL reconstruction" in the electronic search engines PubMed and EBSCOhost (CINAHL, MEDLINE, SPORTDiscus) on July 29, 2015, yielding 1113 abstracts for review. At the conclusion of the search, 14 articles met the inclusion criteria and were included in this review of the literature. Means were calculated for population size, age, follow-up time, and postoperative Tegner scores. Pooled estimates were calculated for postoperative Kujala scores, return to play, total risk of postoperative instability, risk of positive apprehension sign, and risk of reoperation.

RESULTS

The mean patient age associated with MPFL reconstruction was 24.4 years, with a mean postoperative Tegner score of 5.7. The pooled estimated mean postoperative Kujala score was 85.8 (95% CI, 81.6-90.0), with 84.1% (95% CI, 71.1%-97.1%) of patients returning to sports after surgery. The pooled total risk of recurrent instability after surgery was 1.2% (95% CI, 0.3%-2.1%), with a positive apprehension sign risk of 3.6% (95% CI, 0%-7.2%) and a reoperation risk of 3.1% (95% CI, 1.1%-5.0%).

CONCLUSION

A high percentage of young patients return to sports after isolated MPFL reconstruction for chronic patellar instability, with short-term results demonstrating a low incidence of recurrent instability, postoperative apprehension, and reoperations.

Evaluation of Children with Injuries Around the Knee

Knee injuries are common in children and adolescents. Failure to diagnose and treat these injuries in a timely fashion, can lead to potential complications like malunion, growth disturbances, limb length discrepancy, instability of the joint and in long run, early osteoarthritis or loss of physical activity. Frequently, the pediatrician or the primary care physicians are the first health care providers that the child would present to, and hence it is imperative that the presentation of common knee injuries be recognized. Appropriate referral and management of such injuries in children would minimize the likelihood of untoward consequences and optimize long term outcomes. Most preliminary diagnosis can be established based on adequate history and complete physical evaluation of the knee. This information, supplemented by radiographic assessment and if needed, advanced imaging studies like MRI, would help in definitive diagnosis and in formulating treatment plan for these children. The current review would focus on the important characteristics of common knee injuries in children, the recognition of which would help in the initial evaluation of a child.

Classification of Lateral Patellar Instability in Children and Adolescents

There is significant heterogeneity in the literature related to the causes and treatment of patellar instability. To address the multifactorial issue of patellar instability, the first task is to classify the instability pattern. Once a classification system is developed, future studies can differentiate between treatment recommendations and outcomes for each instability pattern. Existing classification systems do not include the entire spectrum of patellar instability patterns. The aim of this article is to review the nomenclature and existing patellar instability classification systems and analyze the different patterns into a comprehensive system.

Pediatric Triplane Ankle Fractures: Impact of Radiographs and Computed Tomography on Fracture Classification and Treatment Planning

BACKGROUND

The purpose of this study was to compare the reliability of triplane fracture classification, displacement measurement, and treatment planning with the use of radiographs with and without computed tomography.

METHODS

One pediatric radiologist, one musculoskeletal radiologist, and three fellowship-trained pediatric orthopaedic surgeons rated a spectrum of twenty-five triplane fractures with use of radiographs alone and then with computed tomography scans on two separate occasions (two to four weeks apart). Raters classified the fracture pattern with use of the Rapariz classification system, measured the maximum intra-articular displacement, and drew the fracture on four outlines of the distal part of the tibia: one lateral view, one anteroposterior view, one axial view above the tibial physis, and one axial view below the physis. Reliability was assessed with kappa values and intraclass correlation coefficients.

RESULTS

The Rapariz triplane fracture classification had poor inter-rater reliability (a kappa of 0.17) and intra-rater reliability (a kappa of 0.31) with radiographs alone but moderate inter-rater reliability (a kappa of 0.41) and intra-rater reliability (a kappa of 0.54) with the addition of computed tomography. After reviewing computed tomography, raters changed the fracture pattern in 46% of ratings, the displacement from ≤2 mm to >2 mm in 39% of ratings, the treatment from nonoperative to operative in 27% of ratings, and either the orientation or number of screws in 41% of ratings.

CONCLUSIONS

Computed tomography had a definite impact on the fracture classification, displacement, and treatment plan, supporting its use as an adjunct to radiographs for the treatment of pediatric triplane fractures.

Consequences of single sport specialization in the pediatric and adolescent athlete

Pediatric and adolescent sports participation has increased with a concomitant increase in injuries. Sports have transitioned from recreational to deliberate, structured activities wherein success is determined by achievement of 'elite' status. This has led to specialization in a single sport with intensive, repetitive activity at younger ages causing physical and emotional consequences, particularly true for the growing athlete who is particularly susceptible to injury. Clinicians caring for this population must understand the epidemiology of youth sports specialization, the unique physiology/structure of this age group, and the potential physical and emotional consequences.

Elastic nailing for pediatric subtrochanteric and supracondylar femur fractures

BACKGROUND

Subtrochanteric and supracondylar femur fractures are difficult injuries to treat in children. Although elastic stable intramedullary nails are commonly used for pediatric femur shaft fractures, there is little information on their effectiveness for managing pediatric subtrochanteric and supracondylar femur fractures.

QUESTIONS/PURPOSES

We (1) evaluated radiographic union rates and fracture alignment after elastic nailing of pediatric subtrochanteric and supracondylar femur fractures, (2) identified complications, and (3) determined risk factors for complications.

METHODS

Between 2005 and 2011, 36 subtrochanteric fractures and eight supracondylar femur fractures were treated with elastic stable intramedullary nails and had complete followup until clinical and radiographic union. Elastic nailing was used for subtrochanteric fractures in children 5 to 12 years of age or after failed spica cast treatment in younger children and for displaced supracondylar fractures in children older than 5 years. Fracture alignment and union were measured on radiographs, and complications were identified from review of patient charts. Patients with and without complications were compared using nonparametric tests to identify risk factors.

RESULTS

All fractures healed; 23 of 33 (70%) subtrochanteric femur fractures and five of seven (71%) supracondylar femur fractures healed with anterior angulation of about 5°. For subtrochanteric fractures, complications included repositioning/removal of nails before radiographic union (n = 4), malunion (n = 2), fracture (n = 1), irritation (n = 1) at nail insertion site, and limb length discrepancy (n = 1); despite these complications, there were 22 (61%) excellent, 12 (33%) satisfactory, and only two (6%) poor outcomes. For supracondylar fractures, complications included infection after nail removal (n = 1) and nail site irritation (n = 2); there were three (38%) excellent, five (62%) satisfactory, and no poor outcomes. Complications were more likely after subtrochanteric fracture during motor vehicle accident (p = 0.045).

CONCLUSIONS

Although complication rates are high with elastic nailing for pediatric subtrochanteric (22%) and supracondylar (38%) femur fractures, elastic nailing represents an important option for difficult-to-manage femur fractures.

LEVEL OF EVIDENCE

Level IV, therapeutic study. See Instructions for Authors for a complete description of levels of evidence.

Prevention of arthrofibrosis after arthroscopic screw fixation of tibial spine fracture in children and adolescents

Arthrofibrosis is a major complication of tibial spine fracture treatment in children, potentially resulting in knee pain, quadriceps weakness, altered gait, decreased function, inability to return to sports, and long-term osteoarthritis. Thus, prevention rather than treatment of arthrofibrosis is desirable. The purpose of this study was to evaluate an aggressive postoperative rehabilitation and early intervention approach to prevent permanent arthrofibrosis after tibial spine fracture treatment and to compare epiphyseal and transphyseal screws for fixation. A consecutive series of 24 patients younger than age 18 with displaced type II and III tibial spine fractures who underwent arthroscopic reduction and screw fixation between 2006 and 2011 were retrospectively reviewed. Final range of motion was compared between patients with epiphyseal (n=12) and transphyseal (n=9) screws. One-third (4 of 12) of patients with epiphyseal screws underwent arthroscopic debridement and screw removal approximately 3 months postoperatively; 3 patients lacked 5° to 15° of extension, 1 experienced pain with extension, and 1 had radiographic evidence of screw pullout, loss of reduction, and resultant malunion. In the transphyseal screw group, 3 patients had 10° loss of extension, and all corrected after arthroscopic debridement and screw removal. The two groups did not significantly differ in time to hardware removal or return to sports or final range of motion. No growth disturbances were identified in patients after transphyseal screw removal. An aggressive approach of postoperative rehabilitation and early intervention after arthroscopic reduction and screw fixation of tibial spine fractures in children was successful in preventing permanent arthrofibrosis.

Intrafocal pinning for distal radius metaphyseal fractures in children

The purpose of this retrospective case control study was to evaluate the results of intrafocal pinning for distal radius metaphyseal fractures in children and to compare these results with conventional pinning. Data were collected from medical records and radiographs from patients who underwent closed reduction and percutaneous pinning for distal radius fracture in a Level I trauma center at the authors' institution between 2008 and 2010. Inclusion criteria included a dorsally angulated metaphyseal fracture without physeal involvement, an open distal radius physis, and a follow-up to radiographic union. A total of 10 patients with intrafocal pinning were compared to 26 patients with conventional pinning. Preoperatively, angulation was greater in patients who received intrafocal pinning than conventional pinning based on anteroposterior radiographs. Postoperatively, the 2 groups did not differ in angulation on either anteroposterior or lateral radiographs. One malunion and 2 pin-related complications occurred in the conventional pinning group, and 1 pin-related complication occurred in the intrafocal pinning group. The 2 groups did not differ by age, sex, side of injury, days to surgery, or initial shortening. This study affirms that the intrafocal pinning technique is an alternative to the conventional pinning technique for the stabilization of displaced metaphyseal distal radius fractures in children. Intrafocal pinning can also be used as a reduction tool for fractures that cannot be reduced by closed manipulation. The complications are comparable between the 2 techniques.

Complications of medial patellofemoral ligament reconstruction in young patients

BACKGROUND

The medial patellofemoral ligament (MPFL) has been recognized as the primary restraint to lateral subluxation of the patella. Reconstruction of the MPFL for patellar instability has demonstrated early clinical success, but postoperative complications have rarely been reported, especially in young patients.

PURPOSE

To assess early complications (<3 years) of MPFL reconstruction in young patients.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

The charts and radiographs of all patients who underwent MPFL reconstruction between 2005 and 2011 were retrospectively reviewed to identify postoperative complications. A complication was considered major if the patient required hospitalization or further surgery. Each complication was analyzed to identify the technical factors related to it.

RESULTS

A total of 179 knees underwent MPFL reconstruction during the study period. There were 38 complications in 29 knees (16.2%), with 34 major and 4 minor. Major complications included recurrent lateral patellar instability (8 patients), knee motion stiffness with flexion deficits (8 patients), patellar fractures (6 patients), and patellofemoral arthrosis/pain (5 patients). Eighteen of 38 (47%) complications were secondary to technical factors and were considered preventable. Female sex and bilateral MPFL reconstructions were risk factors associated with postoperative complications.

CONCLUSION

Complications occurred in 16.2% of MPFL reconstruction surgeries for patellar instability in young patients, with almost half resulting from technical problems. Patients should be counseled preoperatively on the risk of potential complications.

Methicillin-resistant Staphylococcus aureus as a cause of a quadriceps tendon tear

Methicillin-resistant Staphylococcus aureus (MRSA) is an important causative agent in myositis and pyomyositis, but its involvement in quadriceps tendon tears has not been reported until now. In the case reported here, accurate diagnosis was delayed because of the unique presentation, and the infection was mismanaged with corticosteroids because of the presumptive diagnosis of an inflammatory pathology. Subsequently, aggressive surgical and antibiotic management produced a satisfactory outcome. Early detection and appropriate management of these infections are extremely important in preventing limb- and life-threatening consequences.

Arthroscopic posterior capsulolabral repair in a beach-chair position

The authors describe an arthroscopic surgical technique for posterior capsulolabral repair using standard portals while patients are in the beach-chair position. The technique is unique in that the suture anchors are inserted from a superior-to-inferior direction instead of the traditional posterolateral-to-anteromedial direction. It involves the use of a posterolateral or mid-lateral portal through the rotator cuff for suture anchor insertion while viewing from the standard anterior portal. The technique avoids the risk of articular cartilage damage or glenoid rim fracture due to skiving during suture anchor insertion from a posterior or accessory posterior portal.