Simultaneous MPFL reconstruction and guided growth result in low rates of recurrent patellofemoral instability.

PURPOSE: Implant-mediated guided growth (IMGG) is used to address coronal plane deformity in skeletally immature patients. Few studies have reported on IMGG and simultaneous medial patellofemoral ligament (MPFL) reconstruction for paediatric patients with concurrent genu valgum and patellofemoral instability (PFI). This study aimed to report on the outcomes of these simultaneous procedures. MATERIALS AND METHODS: This was a retrospective review of paediatric patients undergoing simultaneous MPFL reconstruction and IMGG between 2016 and 2023. Mechanical lateral distal femoral angle (mLDFA), hip-knee-ankle angle (HKA) and mechanical axis deviation (MAD) were measured on full-length hip-to-ankle plain radiographs. Measurements were taken preoperatively, prior to implant removal and/or at final follow-up with minimum 1-year clinical follow-up. RESULTS: A total of 25 extremities in 22 patients (10 female) underwent simultaneous IMGG and MPFL reconstruction. The mean age at surgery was 12.6 ± 1.7 years. The mean duration of implant retention was 18.6 ± 11.3 months. Nineteen extremities (76%) underwent implant removal by final follow-up. Preoperative HKA corrected from a mean of 5.8 ± 2.3° to -0.8 ± 4.5° at implant removal or final follow-up (p < 0.001), with mLDFA and MAD similarly improving (both p < 0.001). HKA corrected a mean of 0.7 ± 0.9° per month, while mLDFA and MAD corrected a mean of 0.5 ± 0.6°/month and 2 ± 3 mm/month, respectively. At the time of implant removal or final follow-up, 88% of patients demonstrated alignment within 5° of neutral. Only one extremity experienced subsequent PFI (4%). For 14 patients who underwent implant removal with further imaging at a mean of 7.8 ± 4.9 months, only one patient (7%) had a valgus rebound to an HKA > 5°. CONCLUSION: Simultaneous MPFL reconstruction and IMGG provided successful correction of lower extremity malalignment with only one recurrence of PFI. This approach is a reliable surgical option for skeletally immature patients with genu valgum and PFI. LEVEL OF EVIDENCE: Level 4 case series.

Hemiepiphysiodesis for Genu Valgum in Patients With Multiple Hereditary Exostoses.

BACKGROUND: Genu valgum is a well-known feature of multiple hereditary exostoses (MHE). Though prior reports have demonstrated successful treatment with hemiepiphysiodesis, details regarding the correction rate and comparison to an idiopathic population are lacking. This study aimed to detail our institution's experience with guided growth of the knee in patients with MHE and compare this to an idiopathic population. METHODS: All pediatric patients (age 18 and younger) with MHE who underwent lower extremity hemiepiphysiodesis at a tertiary care medical center between January 2016 and December 2022 were retrospectively reviewed. Preoperative and postoperative mechanical lateral distal femoral angle (mLDFA) and medial proximal tibial angle (MPTA, the primary outcomes) were measured in addition to mechanical axis deviation (MAD) and hip-knee-ankle angle (HKA). Patients were 1:2 matched based on age, sex, and physes instrumented to a cohort with idiopathic genu valgum. RESULTS: A total of 21 extremities in 16 patients with MHE underwent hemiepiphysiodesis of the distal femur, proximal tibia, and/or distal tibia. The mean age at surgery was 11.7±2.2 years. Mean MAD corrected from zone 1.9±0.7 to -0.3±1.5, while mLDFA corrected from 83.4±2.9 to 91.7±5.2 degrees and MPTA corrected from 95.3±3.6 to 90.5±4.0 degrees in distal femurs and proximal tibias undergoing guided growth, respectively. Three extremities (14.3%) experienced overcorrection ≥5 degrees managed with observation. There were no differences in correction rates per month for mLDFA (0.54±0.34 vs. 0.51±0.29 degrees, P =0.738) or MPTA (0.31±0.26 vs. 0.50±0.59 degrees, P =0.453) between MHE and idiopathic groups. For 11 extremities in the MHE group with open physes at hardware removal, they experienced a mean recurrence of HKA of 4.0±3.4 degrees at 19-month follow-up. CONCLUSION: Hemiepiphysiodesis corrects lower extremity malalignment in patients with MHE at a similar rate compared with an idiopathic coronal plane deformity population. Rebound deformity of 4 degrees at 19 months after hardware removal in patients with remaining open growth plates should make surgeons conscious of the remaining growth potential when planning deformity correction. LEVEL OF EVIDENCE: Level III.

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.

Association of Quadriceps Tendon Harvest for ACL Reconstruction With Development of Osteochondritis Dissecans of the Patella in Pediatric Patients.

Background: There are various reported complications after primary anterior cruciate ligament reconstruction (ACLR) necessitating additional surgery in skeletally immature patients, regardless of technique and autograft type. Purpose: To analyze the rate and type of complications encountered with soft tissue quadriceps tendon autograft (QTA) for ACLR in patients ≤18 years as well as the overall rate of second surgery, unrelated to the use of the QTA. Study Design: Case series; Level of evidence, 4. Methods: A total of 141 patients ≤18 years who underwent ACLR with a QTA and had minimum 6-month follow-up were included. All patients underwent ACLR by utilizing a full-thickness soft tissue QTA. Complications associated with the QTA harvest site and use of QTA were reported. Results: The mean age of the included cohort (84 men, 57 women) was 14.8 ± 1.6 years. The average follow-up was of 2.0 ± 1.2 years. A total of 30 (21%) patients had a subsequent complication that required surgical intervention; in 11 (8%) patients, the complication was specifically associated with the use of a QTA, whereas in 19 (13%) patients, the complication was related to the ACLR. In addition, 13 (9%) patients underwent a contralateral ACLR procedure. Of the QTA-related complications, 2 patients developed osteochondritis dissecans (OCD)-like lesions in the superior aspect of the patella, 2 patients had injured their quadriceps extensor mechanism and required surgical repair, and 8 patients had a subsequent procedure to remove nonabsorbable sutures used for donor site quadriceps tendon closure. One of the patients who underwent the removal of nonabsorbable sutures also had an arthroscopic debridement of patellar chondral damage. Conclusion: We reported complications encountered with soft tissue QTA for ACLR. The complication rate for QTA harvest was 8%. However, given that the removal of nonabsorbable sutures from the donor site was caused by the surgical technique used, the revised nonsuture-related complication rate for QTA graft harvest was 2%. Although the use of a QTA has recently gained popularity due to its high return-to-sport and low graft-failure rates, surgeons should be aware of the complications associated with using this graft type.

Decreased Effective Patellar Tendon Length following Distalization Tibial Tubercle Osteotomy without Patellar Tendon Tenodesis.

Background: Distalization tibial tubercle osteotomy (TTO) is an effective treatment for improving patellar height in patients with patella alta associated with patellofemoral instability and cartilage lesions. The addition of a patellar tendon tenodesis has been suggested; nonetheless, concerns exist regarding possible increased patellofemoral cartilage stresses. Purpose: To evaluate pre- and postoperative patellar tendon length and alignment parameters on magnetic resonance imaging (MRI), as well as patient-reported outcome measures (PROMs) after distalization TTO without patellar tendon tenodesis. Study Design: Case series; Level of evidence, 4. Methods: Twenty skeletally mature patients who underwent distalization TTO with or without anteromedialization at our institution between December 2014 and August 2021 were included. All patients underwent pre- and postoperative MRIs of the affected knee. The Caton-Deschamps index (CDI), the axial and sagittal tibial tubercle-trochlear groove (TT-TG) distances, the distances from the tibial plateau to the patellar tendon insertion and the tibial tubercle, and the patellar tendon length were assessed. PROMs included the International Knee Documentation Committee Subjective Knee Evaluation Form, the Knee injury and Osteoarthritis Outcome Score-Quality of Life subscale, the Kujala Anterior Knee Pain Scale, and the Veterans RAND 12-Item Health Survey mental and physical component scores. Results: The mean patient age at surgery was 27.4 years (range, 14-42 years). Radiographic parameters demonstrated improved patellar height (CDI decreased from 1.36 to 1.11; P < .001) after distalization TTO. The distance from the tibial plateau to the patellar tendon insertion significantly decreased from 20.1 mm preoperatively to 17.9 mm postoperatively (P < .020), and the patellar tendon length decreased from 53.4 mm preoperatively to 46.0 mm postoperatively (P < .001). The patellar tendon insertion was not distalized after distalization TTO, likely because of scarring of the patellar tendon proximal to the osteotomy site. Patients demonstrated significant pre- to postoperative improvements on all PROMs (P≤ .024 for all ). There were 4 (20%) complications-2 cases of arthrofibrosis, 1 postoperative infection, and 1 osteotomy delayed union. Conclusion: Distalization TTO without patellar tendon tenodesis was associated with improved radiographic outcomes and PROMs. It provides an additional tool for surgical management of patellofemoral pathology with associated patella alta.

Measurement of TT-TG can change with sequential MRIs due to variations in tibiofemoral rotation in patellofemoral instability patients.

PURPOSE: There are various anatomic risk factors for patellofemoral instability (PFI) that help guide surgical treatment, including the tibial tubercle to trochlear groove (TT-TG) distance. However, no study has analysed the temporal changes in TT-TG prior to surgical intervention. This study sought to understand the variations in TT-TG over time for pediatric patients suffering from PFI prior to surgical intervention. The authors hypothesised that the TT-TG would substantially change between time points. METHODS: Patients undergoing medial patellofemoral ligament (MPFL) reconstruction between 2014 and 2019 by one of two fellowship-trained orthopaedic surgeons were identified. Patients were included if they had two preoperative magnetic resonance imaging (MRI) performed on the same knee within 7.5 months of each other prior to any surgical intervention and had an initial TT-TG greater than 10 mm. RESULTS: After considering 251 patients for inclusion, 21 patients met the final inclusion criteria. The mean age was 14.5 ± 2.5 years and 61.9% were female. TT-TG was initially noted to be 15.1 ± 1.8 mm. At mean time after sequential MRIs of 5.0 ± 1.9 months, TT-TG was noted to be 16.7 ± 3.2 mm. The differences between initial and subsequent TT-TG ranged from a 21.2% decrease to a 61.1% increase, with a mean difference of an 11.3% increase. Comparison between initial and subsequent TT-TG values demonstrated a significant difference (p = 0.017). Change in tibiofemoral rotation ranged from -9.2° to 7.5°. When comparing the change in TT-TG to change in tibiofemoral rotation, a significant correlation was found (p = 0.019). CONCLUSION: Despite only a mean time between MRIs of 5 months, variations in TT-TG ranged from a decrease of 21.2% to an increase of 61.1%. The significant relationship between the changes in TT-TG and changes in tibiofemoral rotation between MRIs suggest that TT-TG measurements may vary due to variations in tibiofemoral rotation at the time of individual MRIs. LEVEL OF EVIDENCE: Level IV.

Association of Lateral Extra-Articular Tenodesis With Improved Graft Maturity on MRI 2 Years After ACL Reconstruction With Quadriceps Tendon Autograft in Skeletally Immature Athletes.

Background: Quadriceps tendon autograft (QTA) has recently gained popularity in the treatment of anterior cruciate ligament (ACL) ruptures in pediatric patients. The addition of lateral extra-articular tenodesis (LET) to an ACL reconstruction (ACLR) has been found to reduce the risk of ACL retear in high-risk patients. Purpose: To (1) compare ACL graft maturity using signal intensity ratios (SIRs) on magnetic resonance imaging (MRI) scans in skeletally immature patients undergoing ACLR with QTA either with or without concomitant LET and (2) evaluate LET safety by calculating the physeal disturbance-related reoperation rate in the ACLR+LET group. Study Design: Cohort study; Level of evidence, 3. Methods: The records of patients aged ≤18 years who underwent ACLR between 2015 and 2021 were reviewed retrospectively. Patients undergoing ACLR with QTA who had open distal femoral and proximal tibial physes on MRI scans and a minimum 2-year follow-up data were included. SIR values were measured on sagittal MRI scans by averaging the signal at 3 regions of interest along the ACL graft and dividing by the signal of the posterior cruciate ligament at its insertion. Statistical analysis was performed to evaluate differences in SIR values at 6 months, 1 year, and 2 years postoperatively in patients who underwent ACLR alone versus ACLR+LET. Results: Overall, 29 patients were included in the study: 16 patients in the ACLR+LET group and 13 patients in the ACLR-only group. There were no significant differences in SIR values between groups at the 6-month or 1-year postoperative timepoints. At 2 years postoperatively, the median SIR of the ACLR+LET group was significantly lower than that of the ACLR-only group on both univariate (1.33 vs 1.86, respectively, P = .0012) and multivariate regression analyses adjusting for both sex and surgical technique (ß = -0.49 [95% CI, -0.91 to -0.05]; P = .029). There were no cases of reoperation for physeal disturbance in patients who underwent ACLR+LET. Conclusion: The addition of LET to an ACLR with QTA was associated with lower average SIR values and thus improved graft maturity at 2 years postoperatively compared with ACLR alone in skeletally immature patients. The addition of LET to an ACLR was found to be safe in skeletally immature patients.

Pigmented villonodular synovitis/giant cell tumor in the knee.

PURPOSE OF REVIEW: Pigmented villonodular synovitis (PVNS) is a rare diagnosis in pediatric patients and commonly presents with symptoms of swelling and pain. Early diagnosis is important to prevent secondary degeneration into the subchondral bone. This review will analyze the etiology, clinical signs/symptoms, diagnosis, treatment, and recent literature on PVNS in the pediatric population. RECENT FINDINGS: Many theories of PVNS etiology have been described in the literature; however, an inflammatory response has been most widely accepted. PVNS can occur in any joint, but most commonly in the knee. The most common treatment for PVNS is synovectomy, and long-term follow-up is necessary to detect disease persistence or recurrence. SUMMARY: Although uncommon, PVNS does occur in the pediatric population and this diagnosis should be included in the differential of atraumatic joint swelling and pain.

BrAIST-Calc: Prediction of Individualized Benefit From Bracing for Adolescent Idiopathic Scoliosis.

STUDY DESIGN: Prospective multicenter study data were used for model derivation and externally validated using retrospective cohort data. OBJECTIVE: Derive and validate a prognostic model of benefit from bracing for adolescent idiopathic scoliosis (AIS). SUMMARY OF BACKGROUND DATA: The Bracing in Adolescent Idiopathic Scoliosis Trial (BrAIST) demonstrated the superiority of bracing over observation to prevent curve progression to the surgical threshold; 42% of untreated subjects had a good outcome, and 28% progressed to the surgical threshold despite bracing, likely due to poor adherence. To avoid over-treatment and to promote patient goal setting and adherence, bracing decisions (who and how much) should be based on physician and patient discussions informed by individual-level data from high-quality predictive models. MATERIALS AND METHODS: Logistic regression was used to predict curve progression to <45° at skeletal maturity (good prognosis) in 269 BrAIST subjects who were observed or braced. Predictors included age, sex, body mass index, Risser stage, Cobb angle, curve pattern, and treatment characteristics (hours of brace wear and in-brace correction). Internal and external validity were evaluated using jackknifed samples of the BrAIST data set and an independent cohort (n=299) through estimates of discrimination and calibration. RESULTS: The final model included age, sex, body mass index, Risser stage, Cobb angle, and hours of brace wear per day. The model demonstrated strong discrimination ( c -statistics 0.83-0.87) and calibration in all data sets. Classifying patients as low risk (high probability of a good prognosis) at the probability cut point of 70% resulted in a specificity of 92% and a positive predictive value of 89%. CONCLUSION: This externally validated model can be used by clinicians and families to make informed, individualized decisions about when and how much to brace to avoid progression to surgery. If widely adopted, this model could decrease overbracing of AIS, improve adherence, and, most importantly, decrease the likelihood of spinal fusion in this population.

Strong Association Between Growth Hormone Therapy and Proximal Tibial Physeal Avulsion Fractures in Children and Adolescents: A Case-Control Study.

BACKGROUND: Published literature describes slipped capital femoral epiphysis as a complication of recombinant human growth hormone (rhGH) therapy that may be related to decreased physeal strength. The purpose of the current investigation was to utilize a case-control study design to determine whether a greater proportion of pediatric patients sustaining physeal avulsion fractures of the proximal tibia were undergoing rhGH therapy at the time of injury compared with a cohort of matched controls. METHODS: A case-control design study design was utilized. Patients 4 to 18 years of age with proximal tibial physeal avulsion fractures (cases) or midshaft tibial fractures (controls) at our institution from February 1, 2016, to May 4, 2023, were identified. Cases and controls were matched 1:1 on the basis of age (within 1 year), sex, and body mass index (within 3 kg/m 2 ). A total of 132 patients were included in the analysis (mean age, 13 ± 2 years). rhGH exposure was compared using conditional logistic regression with Firth correction. RESULTS: We found that 11% of the patients with a proximal tibial physeal avulsion fracture were on rhGH therapy at the time of injury compared with 0% of patients with midshaft tibial fractures (odds ratio [OR], 15.0; 95% confidence interval [CI], 1.8 to 1,946.7; p = 0.007). There was no significant difference in the proportion of sports-related injuries between cases (70%) and controls (67%) (OR, 1.15; 95% CI, 0.55 to 2.39; p = 0.85). Among subjects with proximal tibial avulsion fractures, the proportion requiring surgery did not differ significantly between patients receiving and those not receiving rhGH therapy (43% versus 41%, respectively; p = 0.99). CONCLUSIONS: This study demonstrates that the proportion of subjects who sustained proximal tibial physeal avulsion fractures and were receiving recombinant human growth hormone therapy at the time of injury was significantly greater than that of an age, sex, and body mass index-matched control group with midshaft tibial fractures (11% versus 0%, respectively, representing 15-times greater odds of exposure). This quantifies a previously unreported serious orthopaedic complication associated with rhGH therapy. LEVEL OF EVIDENCE: Prognostic Level III . See Instructions for Authors for a complete description of levels of evidence.

Stepwise lengthening of quadriceps extensor mechanism for severe obligatory and fixed patella dislocators: Four-year clinical and surgical outcomes.

OBJECTIVES: The purpose of this study was to report clinical and surgical outcomes of medial patellofemoral ligament reconstruction (MPFLR) and concomitant quadriceps lengthening to treat fixed and obligatory patellofemoral instability (PFI) in the pediatric population. METHODS: Patients with obligatory or fixed PFI who underwent simultaneous MPFLR and quadriceps lengthening from 2008 to 2020 were reviewed. Of the 413 records, 24 fit the inclusion criteria. Demographic information, surgical details, associated diagnoses, and outcome measures were collected for each knee. Complications and additional surgeries were also obtained. RESULTS: The final cohort included 20 patients (10 male, 10 female), with a total of 24 knees. The average age at the time of surgery was 11.9 â€‹± â€‹3.1 (5.4-17.3). Seventeen were obligatory dislocators in flexion and 7 were fixed dislocators. Average follow-up was 4.3 â€‹± â€‹2.4 (1.3-9.4) years. One patient was lost to follow-up and excluded from the study. The mean outcome measures were as followed; KOOS 82, HSS Pedi-FABS 9, IKDC 76, Kujala 78, BPII 67, and SANE 90. Six patients had subsequent instability episodes. Ten patients had a subsequent surgery. CONCLUSIONS: Reports on quadriceps lengthening to treat PFI in the pediatric population are rare. Six (25 â€‹%) of the 24 knees included had subsequent PFI. Although this is a high rate of recurrent instability, no second surgeries were indicated for infection, extensor mechanism weakness, or contracture. The authors conclude that simultaneous MPFLR and stepwise quadriceps lengthening can be used to effectively manage fixed and obligatory PFI in this difficult patient population. LEVEL OF EVIDENCE: IV.

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.

Anterior Displacement of Tibial Spine Fractures: Does Anatomic Reduction Matter?

Background: Operative treatment of displaced tibial spine fractures consists of fixation and reduction of the fragment in addition to restoring tension of the anterior cruciate ligament. Purpose: To determine whether residual displacement of the anterior portion of a tibial spine fragment affects the range of motion (ROM) or laxity in operatively and nonoperatively treated patients. Study Design: Cohort study; Level of evidence, 3. Methods: Data were gathered from 328 patients younger than 18 years who were treated for tibial spine fractures between 2000 and 2019 at 10 institutions. ROM and anterior lip displacement (ALD) measurements were summarized and compared from pretreatment to final follow-up. ALD measurements were categorized as excellent (0 to <1 mm), good (1 to <3 mm), fair (3 to 5 mm), or poor (>5 mm). Posttreatment residual laxity and arthrofibrosis were assessed. Results: Overall, 88% of patients (290/328) underwent operative treatment. The median follow-up was 8.1 months (range, 3-152 months) for the operative group and 6.7 months (range, 3-72 months) for the nonoperative group. The median ALD measurement of the cohort was 6 mm pretreatment, decreasing to 0 mm after treatment (P < .001). At final follow-up, 62% of all patients (203/328) had excellent ALD measurements, compared with 5% (12/264) before treatment. Subjective laxity was seen in 11% of the nonoperative group (4/37) and 5% of the operative group (15/285; P = .25). Across the cohort, there was no association between final knee ROM and final ALD category. While there were more patients with arthrofibrosis in the operative group (7%) compared with the nonoperative group (3%) (P = .49), this was not different across the ALD displacement categories. Conclusion: Residual ALD was not associated with posttreatment subjective residual laxity, extension loss, or flexion loss. The results suggest that anatomic reduction of a tibial spine fracture may not be mandatory if knee stability and functional ROM are achieved.

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.

Validation of the ACL-RSI Scale in Pediatric and Adolescent Patients.

BACKGROUND: The Anterior Cruciate Ligament-Return to Sport after Injury (ACL-RSI) scale is a 12-item questionnaire assessing psychological readiness to return to sport after anterior cruciate ligament reconstruction. It has been validated for use in adults in multiple languages and in an abbreviated 6-question short form. Additionally, literature has been published using this scale in pediatric and adolescent populations, however it has not yet been validated for use with them. PURPOSE: To validate the ACL-RSI scale for use with pediatric and adolescent patients. STUDY DESIGN: Cohort study (Diagnosis); Level of evidence, 2. METHODS: Scores of 6- and 12-item ACL-RSI scales for patients undergoing return-to-sport readiness testing 6 to 8 months after anterior cruciate ligament reconstruction were analyzed. Convergent validity testing was performed against the International Knee Documentation Committee (IKDC)/Pediatric IKDC score, Single Assessment Numeric Evaluation (SANE) score, and peak torque asymmetry of knee flexion and extension using Spearman correlations. Discriminant validity testing was performed against age (Spearman correlation), body mass index (Spearman correlation), and sex (Mann-Whitney U test). Reliability testing was performed by calculating Cronbach's alpha. Floor and ceiling effects were assessed by calculating the number of minimum and maximum scores in the cohort. RESULTS: A total of 51 patients were included in the final analysis. The mean age at surgery was 15.2 ± 2.2 years, and 51.0% were female. The 6- and 12-item ACL-RSI scales demonstrated a strong significant positive correlation with IKDC/Pediatric IKDC scores (R = 0.723 and 0.717, respectively; P < .001) and moderate significant positive correlation with Single Assessment Numeric Evaluation scores (R = 0.516 and 0.502, respectively; P < .001) Age at surgery, body mass index, and sex were not correlated with either ACL-RSI scale. Cronbach's alpha values of the 12- and 6-item ACL-RSI scales in this population were 0.959 and 0.897, respectively. For both the 12- and the 6-item ACL-RSI scales, no floor or ceiling effects were found as the minimum score (0) was not observed in either version, and the maximum score (100) was only observed twice (3.9%) in both versions. CONCLUSION: The ACL-RSI scale is valid to use with pediatric and adolescent patients. The 6-item scale may be a better choice because it has fewer redundancies and minimizes the risk of questionnaire fatigue.

Fixation Strategy Does Not Affect Risk of Growth Disturbance After Surgical Treatment of Pediatric Tibial Spine Fracture.

Purpose: To characterize growth abnormalities after surgical treatment of tibial spine fractures and to investigate risk factors for these abnormalities. Methods: A retrospective analysis of children who underwent treatment of tibial spine fractures between January 2000 and January 2019 was performed, drawing from a multicenter cohort among 10 tertiary care children's hospitals. The entire cohort of surgically treated tibial spine fractures was analyzed for incidence and risk factors of growth disturbance. The cohort was stratified into those who were younger than the age of 13 years at the time of treatment in order to evaluate the risk of growth disturbance in those with substantial growth remaining. Patients with growth disturbance in this cohort were further analyzed based on age, sex, surgical repair technique, implant type, and preoperative radiographic measurements with χ2, t-tests, and multivariate logistic regression. Results: Nine patients of 645 (1.4%) were found to have growth disturbance, all of whom were younger than 13 years old. Patients who developed growth disturbance were younger than those without (9.7 years vs 11.9 years, P = .019.) There was no association with demographic factors, fracture characteristics, surgical technique, hardware type, or anatomic placement (i.e., transphyseal vs physeal-sparing fixation) and growth disturbance. Conclusions: In this study, we found an overall low incidence of growth disturbance after surgical treatment of tibial spine fractures. There was no association with surgical technique and risk of growth disturbance. Level of Evidence: Level III, retrospective comparative study.

Male sex is an independent risk factor for patellar osteochondral fractures following acute patellar dislocation in pediatric patients.

PURPOSE: Although most patellar dislocations are associated with medial patellofemoral ligament (MPFL) injury, many patients also sustain concomitant patellar osteochondral fractures following a patellar dislocation. Few prior studies have described or evaluated risk factors for patellar osteochondral fractures in pediatric patients. The purpose of the present study was to describe the incidenceand location of patellar osteochondral fractures following acute patellar dislocation in pediatric patients. In addition, we described risk factors for patellar osteochondral fractures in this population. We hypothesized that most fractures would occur at the inferomedial quadrant of the patella following a traumatic injury mechanism. METHODS: Following Institutional Review Board approval, the electronic medical record was queried to identify pediatric patients ≤ 18 years old who underwent MPFL reconstruction (MPFLR) or non-operative treatment for patellar instability between July 2016 and February 2020. Osteochondral fractures were defined as full-thickness chondral injuries with attached subchondral bone or purely osseous injuries measuring ≥ 3 mm (mm) in at least two magnetic resonance imaging (MRI) planes. Patients were included in the study if they had complete preoperative x-ray and MRI studies with minimum 6-month follow-up. Patients were excluded if they had incomplete imaging, isolated chondral fractures, or less than 6 months follow-up. Univariate analysis was used to identify patient factors associated with osteochondral fractures. Multivariate regression analysis was used to identify risk factors for osteochondral fractures. RESULTS: Sixty patients (63 knees) were included in the study, 15 (23.8%) of whom had a patellar osteochondral fracture. The majority of osteochondral fractures (87%) involved the inferomedial quadrant of the patella. Univariate analysis showed an association between male sex (p = 0.041), skeletal immaturity (p = 0.028), and decreased patellar tilt (p = 0.021) and patellar osteochondral fractures. Multivariate regression analysis identified male sex as an independent risk factor for osteochondral fractures (relative risk: 4.8, 95% confidence interval [CI]: 1.08-20.9, p = 0.039). No patients had recurrent dislocation at minimum 6-month follow-up. All patients with osteochondral fractures returned to sports at most recent follow up. CONCLUSION: In this study, 23% of pediatric patients with acute patellar dislocations have a concomitant patellar osteochondral fracture. The majority of patellar osteochondral fractures involve the inferomedial quadrant of the patella. Male sex is an independent risk factor for patellar osteochondral fractures, and skeletal immaturity is associated with patellar osteochondral fractures in this population. LEVEL OF EVIDENCE: Level III.

Posterior Cruciate Ligament Femoral Avulsion Fractures in Pediatric Patients: A Report of 2 Interesting Surgical Cases.

CASE: This report describes 2 cases of femoral-sided posterior cruciate ligament (PCL) avulsion injuries. A 10-year-old male patient presented with a chronic nonunion of a bony PCL femoral avulsion. In addition, a 4-year-old boy presented with an acute, displaced PCL femoral avulsion off the medial femoral condyle. Both injuries were repaired using arthroscopic techniques. CONCLUSION: Femoral-sided PCL avulsions are very rare in pediatric patients and have not been reported often. We hope to increase the awareness of PCL femoral avulsion injuries in pediatric patients by describing 2 unique cases.

Tibial spine fractures: State of the art.

Tibial spine fractures (TSFs) are avulsion fractures at the site where the anterior cruciate ligament inserts onto the tibial eminence. TSFs typically affect children and adolescents aged 8-14 years. The incidence of these fractures has been reported to be approximately 3 per 100,000 per year, but the rising involvement of paediatric patients in sporting activities is increasing the number of these injuries. TSFs are historically classified on plain radiographs according to the Meyers and Mckeever classification system, which was introduced in 1959, but the renewed interest in these fractures and the increasing use of magnetic resonance imaging led to the recent development of a new classification system. A reliable grading protocol for these lesions is paramount to guide orthopedic surgeons in determining the correct treatment for young patients and athletes. TSFs can be addressed conservatively in the case of nondisplaced or reduced fractures or surgically in the case of displaced fractures. Different surgical approaches and, specifically, arthroscopic techniques have been described in recent years to ensure stable fixation while limiting the risk of complications. The most common complications associated with TSF are arthrofibrosis, residual laxity, fracture nonunion or malunion, and tibial physis growth arrest. We speculate that advances in diagnostic imaging and classifications, combined with greater knowledge of treatment options, outcomes, and surgical techniques, will likely reduce the occurrence of these complications in paediatric and adolescent patients and athletes, allowing them a timely return to sports and everyday activities.

Tibial Spine Fractures in the Child and Adolescent Athlete: A Systematic Review and Meta-analysis.

BACKGROUND: Tibial spine fractures (TSFs) are uncommon injuries that may result in substantial morbidity in children. A variety of open and arthroscopic techniques are used to treat these fractures, but no single standardized operative method has been identified. PURPOSE: To systematically review the literature on pediatric TSFs to determine the current treatment approaches, outcomes, and complications. STUDY DESIGN: Meta-analysis; Level of evidence, 4. METHODS: A systematic review of the literature was performed in accordance with the PRISMA (Preferred Reporting Items for Systematic Review and Meta-Analyses) guidelines using PubMed, Embase, and Cochrane databases. Studies evaluating treatment and outcomes of patients <18 years old were included. Patient demographic characteristics, fracture characteristics, treatments, and outcomes were abstracted. Descriptive statistics were used to summarize categorical and quantitative variables, and a meta-analytic technique was used to compare observational studies with sufficient data. RESULTS: A total of 47 studies were included, totaling 1922 TSFs in patients (66.4% male) with a mean age of 12 years (range, 3-18 years). The operative approach was open reduction and internal fixation in 291 cases and arthroscopic reduction and internal fixation in 1236 cases; screw fixation was used in 411 cases and suture fixation, in 586 cases. A total of 13 nonunions were reported, occurring most frequently in Meyers and McKeever type III fractures (n = 6) and in fractures that were treated nonoperatively (n = 10). Arthrofibrosis rates were reported in 33 studies (n = 1700), and arthrofibrosis was present in 190 patients (11.2%). Range of motion loss occurred significantly more frequently in patients with type III and IV fractures (P < .001), and secondary anterior cruciate ligament (ACL) injury occurred most frequently in patients with type I and II fractures (P = .008). No statistically significant differences were found with regard to rates of nonunion, arthrofibrosis, range of motion loss, laxity, or secondary ACL injury between fixation methods (screw vs suture). CONCLUSION: Despite variation in TSF treatment, good overall outcomes have been reported with low complication rates in both open and arthroscopic treatment and with both screw and suture fixation. Arthrofibrosis remains a concern after surgical treatment for TSF, but no significant difference in incidence was found between the analysis groups. Larger studies are necessary to compare outcomes and form a consensus on how to treat and manage patients with TSFs.