Pattern of strength recovery differences Exist in Adolescent athletes after anterior cruciate ligament reconstruction when using quadriceps versus Hamstring tendon autograft.

OBJECTIVES: To compare the timeline for post-operative quadriceps and hamstrings strength recovery following anterior cruciate ligament reconstruction (ACLR) using either a quadriceps tendon (QT) or hamstring tendon (HT) autograft. METHODS: Patients (≤18 years) who underwent ACLR using autograft QT or HT were included. Isokinetic strength was extracted at 3, 6, and 12 months post-operatively. Effects of time and graft type on quadriceps or hamstring limb symmetry index (qLSI/hLSI) was assessed with two-way repeated measures ANOVA. Between group differences at each time point were assessed with unpaired t-tests. Chi-square and Kaplan-Meir analysis analyzed the proportions of subjects able to achieve ≥90% LSI. RESULTS: A total of 75 subjects (QT n = 38 HT n = 37,15.8 years) were included. There were significant differences in qLSI, with greater symmetry within the HT group at all time points. A higher proportion of subjects with HT grafts were able to achieve ≥90% qLSI within 12 months of surgery (81% vs 45%, p = 0.001). CONCLUSION: Compared to those with HT autografts, adolescents with QT autografts demonstrate a prolonged timeline for quadriceps recovery. While mean strength values above 90% are achieved, a significantly lower percentage of QT patients are able to achieve 90% qLSI by 12 months post-op.

Patellar osteochondritis dissecans: maturation-dependent patellofemoral joint characteristics.

BACKGROUND: The likelihood of healing of osteochondritis dissecans decreases with skeletal maturity and there are theories that abnormal biomechanical forces contribute to the development and progression of these lesions. OBJECTIVE: To characterize, according to regional skeletal maturity, the morphology and alignment indices of the patellofemoral joint on MRI in patients with patellar osteochondritis dissecans. MATERIALS AND METHODS: MRI examinations of patients with patellar osteochondritis dissecans obtained between January 2008 and May 2023 were retrospectively reviewed to determine regional skeletal maturity, osteochondritis dissecans lesion size and location, patellar and trochlear morphology (Wiberg/Dejour classifications), and to calculate trochlear sulcus angles, trochlear depth index, lateral trochlear inclination, Insall-Salvati index, Caton-Deschamps index, patellar tendon-lateral trochlear ridge, and tibial tubercle-trochlear groove distances. Values were compared between skeletally immature and mature groups. RESULTS: Sixty-eight children (22 girls, 46 boys, age: 14.0 ± 1.7 years) yielded 74 knees with patellar osteochondritis dissecans lesions, 14 (19%) of which were skeletally mature. The most common anatomic location was over the central patella [median ridge (34/74 - 46%) on the axial images and over the middle third (45/74 - 61%) on the sagittal images]. Overall, mean trochlear sulcus angle (high, 151 ± 11°), trochlear depth index (low, 2.8 ± 1.4 mm), and Insall-Salvati index (borderline, 1.3 ± 0.1) were abnormal for the entire sample. Skeletally mature knees were significantly more likely to have higher (more dysplastic) Dejour types when compared to skeletally immature knees (p < 0.01). Knees in the mature group, compared to immature, had significantly more abnormal mean lateral trochlear inclination (15 ± 8° vs. 19 ± 6°, p = 0.03) and patellar tendon-lateral trochlear ridge distance (5.55 ± 4.31 mm vs. 2.89 ± 4.69 mm, p = 0.04). Half of the knees had ≥ 4 abnormal features that predispose to patellofemoral maltracking; mature knees were significantly (p = 0.02) more likely to have a higher number of abnormal features (> 6 features, 7/14, 50.0%) versus immature knees (0-3 features, 33/60, 55.0%). CONCLUSION: In children with patellar osteochondritis dissecans, abnormal patellofemoral morphology and alignment indices were common in all patients and more severe in mature knees.

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.

Pediatric thrower's elbow: maturation-dependent MRI findings in symptomatic baseball players.

BACKGROUND: Elbow pain is common among youth baseball players and elbow MRI is increasingly utilized to complement the clinical assessment. OBJECTIVE: To characterize, according to skeletal maturity, findings on elbow MRI from symptomatic youth baseball players. MATERIALS AND METHODS: This IRB-approved, HIPAA-compliant retrospective study included pediatric (<18 years of age) baseball players with elbow pain who underwent MRI examinations between 2010 and 2021. Two radiologists, blinded to the outcome, independently reviewed examinations to categorize skeletal maturity and to identify osseous and soft tissue findings with consensus used to resolve discrepancies. Findings were compared between skeletally immature and mature patients and logistic regression models identified predictors of surgery. RESULTS: This study included 130 children (115 boys, 15 girls): 85 skeletally immature and 45 mature (12.8±2.3 and 16.2±1.0 years, respectively, p<0.01). Kappa coefficient for interobserver agreement on MRI findings ranged from 0.64 to 0.96. Skeletally immature children, when compared to mature children, were more likely to have elbow effusion (27%, 23/85 vs 9%, 4/45; p=0.03), medial epicondyle marrow edema (53%, 45/85 vs 16%, 7/45; p<0.01), avulsion fracture (19%, 16/85 vs 2%, 1/45; p=0.02), and juvenile osteochondritis dissecans (OCD, 22%, 19/85 vs 7%, 3/45; p=0.04), whereas skeletally mature children were more likely to have sublime tubercle marrow edema (49%, 22/45 vs 11%, 9/85; p<0.01) and triceps tendinosis (40%, 18/45 vs 20%, 17/85; p=0.03). Intra-articular body (OR=4.2, 95% CI 1.5-47.8, p=0.02) and osteochondritis dissecans (OR=3.7, 95% CI 1.1-11.9, p=0.03) were independent predictors for surgery. CONCLUSION: Differential patterns of elbow MRI findings were observed among symptomatic pediatric baseball players based on regional skeletal maturity. Intra-articular body and osteochondritis dissecans were independent predictors of surgery.

Patella and Trochlea Osteochondritis Dissecans: Demographics and Treatment Paradigms.

OBJECTIVE: Previous research on patellar and trochlear groove osteochondritis dissecans (OCD) is limited by small sample sizes. This study aims to describe the presentation of patients with OCD lesions of the patella and trochlea and characterize the outcomes of operative and nonoperative treatments. METHODS: This retrospective cohort study identified all patients from a single institution from 2008 to 2021 with patellar and/or trochlear OCD lesions. Patients were excluded from the study if surgical records were unavailable or if the patient had knee surgery for a different injury at index surgery or in the 12 months postoperative. Minimum follow-up was 12 months. Outcomes included a return to sports (RTS), pain resolution, radiographic healing, and treatment "success" (defined as full RTS, complete pain resolution, and full healing on imaging). RESULTS: A total of 68 patients (75 knees) were included-45 (60%) with patellar OCD and 30 (40%) with trochlear. Of the patients, 69% were males. The median age at knee OCD diagnosis was 14 years. At the final follow-up, 62% of knees (n = 44) recovered sufficiently to allow a full RTS and 54% of knees (n = 39) had full pain resolution. Of the 46 knees with radiographic imaging at least 1 year apart, 63% had full healing of the lesion. There was no significant difference in RTS, pain resolution, radiographic healing, or overall success when comparing treatments. CONCLUSIONS: This study provides valuable epidemiologic demographic and outcome data regarding the scarcely reported patellar and trochlear OCD. While over half of patients fully returned to sports and reported full pain resolution, a large proportion continued to experience symptoms over a year after presentation. Future research should aim to better define the treatment algorithms for these OCD subtypes. LEVEL OF EVIDENCE: Level III.

Maturation-dependent patterns of knee injuries among symptomatic pediatric soccer players on MRI.

OBJECTIVE: To systematically investigate the prevalence of knee MRI findings among symptomatic pediatric soccer players with respect to skeletal maturity and to identify predictors of surgery. METHODS: This IRB-approved, HIPAA-compliant retrospective study included soccer players (< 18 years of age) who underwent MRI examinations in the past 5 years (2018-2023). Two radiologists retrospectively and independently reviewed all examinations to categorize skeletal maturity and to identify osseous and soft tissue findings. Findings were compared between maturation groups, and logistic regression models were used to identify predictors of surgery. RESULTS: Ninety-seven players (45 boys, 52 girls) included 39 skeletally immature, 21 maturing, and 37 mature knees. Kappa coefficient for interobserver reliability ranged between 0.65 and 1.00. Osgood-Schlatter disease (OSD) was more common among immature than maturing and mature knees (25% vs 14% and 5%, p = 0.04); anterior cruciate ligament (ACL) injury was more common among maturing and mature than immature knees (59% and 48%, vs 15%, p < 0.01); and meniscal tears were more common among mature than immature and maturing knees (medial, 41% vs 18% and 14%, p = 0.03; lateral, 43% vs 21% and 19%, p = 0.04). Players in the mature group were more likely to undergo surgery (p = 0.01). The presence of an effusion (OR = 19.5, 95% CI 2.8-240.9, p = 0.01), ACL injury (OR = 170.0, 95% CI 1.3-6996.9, p < 0.01), and lateral meniscal tears (OR = 10.8, 95% CI 1.8-106.1, p = 0.02) were independent predictors of surgery. CONCLUSION: Differential patterns of injury were found among symptomatic pediatric soccer players; the presence of an effusion, ACL injury, and lateral meniscal tears were independent predictors of surgery, likely contributing to the higher rates of surgery among skeletally mature players.

Postoperative Strength Differences at Short-Term Follow-up Vary Based on Autograft Harvest Site After Adolescent Transphyseal Anterior Cruciate Ligament Reconstruction.

PURPOSE: To compare the clinical and patient-reported outcomes of adolescent patients who underwent anterior cruciate ligament reconstruction (ACLR) with quadriceps tendon (QT) versus hamstring tendon (HT) autograft. METHODS: This was a retrospective cohort study of adolescent patients aged 18 years or younger treated at a single tertiary care children's hospital who underwent primary transphyseal ACLR using QT or HT between January 2018 and December 2019. All patients had minimum 6-month follow-up. Outcomes included isokinetic strength testing, postoperative Patient-Reported Outcomes Measurement Information System and International Knee Documentation Committee scores, and complications; these were compared between the QT and HT cohorts. RESULTS: A total of 84 patients (44 HT and 40 QT patients) were included. The QT cohort had a higher proportion of male patients (62.5% vs 34.1%, P = .01). At 3 months, HT patients had a lower hamstring-quadriceps (H/Q) strength ratio (60.7 ± 11.0 vs 79.5 ± 18.6, P < .01) and lower Limb Symmetry Index in flexion (85.6 ± 16.1 vs 95.5 ± 15.7, P = .01) whereas QT patients had a lower Limb Symmetry Index in extension (67.3 ± 9.5 vs 77.4 ± 10.7, P < .01). The H/Q ratio at 6 months was lower in HT patients (59.4 ± 11.5 vs 66.2 ± 7.5, P < .01). Patient-Reported Outcomes Measurement Information System and International Knee Documentation Committee scores were not different at 3 months or latest follow-up. QT patients had more wound issues (20.0% vs 2.3%, P = .01). Patients receiving HT autograft had more ipsilateral knee injuries (18.2% vs 2.5%, P = .03), but there was no difference in graft failure for ACLR using HT versus QT (9.1% vs 2.5%, P = .36). CONCLUSIONS: There were no differences in patient-reported outcome measures between patients receiving QT autografts and those receiving HT autografts. Patients with QT grafts had more postoperative wound issues but a lower rate of ipsilateral knee complications (graft failure or meniscal tear). Differences in quadriceps and hamstring strength postoperatively compared with the contralateral limb were observed for adolescent ACLR patients receiving QT and HT autografts, respectively. This contributed to higher H/Q ratios seen at 3 and 6 months postoperatively for patients receiving QT autografts. LEVEL OF EVIDENCE: Level III, retrospective comparative therapeutic study.

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.

Disparate Impact: How Does Social Deprivation Affect Patient-reported Outcomes After ACL Reconstruction in Children and Adolescents?

BACKGROUND: Research has indicated that lower socioeconomic status is associated with delays in the treatment of anterior cruciate ligament (ACL) injuries; however, there is a paucity of literature evaluating its association with patient-reported outcomes (PROs). Using the Area Deprivation Index (ADI), a validated proxy for socioeconomic status, the study aimed to determine how relative socioeconomic disadvantage is related to PROs after primary ACL reconstruction (ACLR) in pediatric patients. METHODS: This retrospective cohort study included all patients 18 years old or above who underwent primary ACLR at an academic institution between 2018 and 2021. Exclusion criteria included multiligament injury, congenital ACL absence, and absent outcomes data. The minimum follow-up was 6 months. A Patient-reported Outcomes Measurement Information System (PROMIS) 50 Pediatric self-report questionnaire was completed at postoperative visits, and domain scores for pain, physical function/mobility, fatigue, anxiety, depression, and peer relationships were generated. The National ADI percentile was calculated using the patients' addresses. Patients were divided into quartiles (low, moderate, moderate-severe, and severe ADI), and comparative analyses were performed to determine the relationship between ADI and PROMIS. RESULTS: A total of 413 patients were identified, including 49% (n=207), 33% (n=139), 11% (n=48), and 7% (n=30) from the low, moderate, moderate-severe, and severe deprivation areas, respectively. As compared with those in the low-deprivation quartile, patients in the severe deprivation quartile had delayed time to the first clinic visit (11 vs. 16.5 d, P=0.044) and surgery (51 vs. 80 d, P=0.004). There were no differences in the number of additional procedures required at index surgery. All quartiles had progressive improvements in physical function/mobility and pain scores throughout recovery, but at 9 months, there was significantly more pain in the severe deprivation cohort, despite no difference in self-reported physical function and mobility. Those with severe socioeconomic disadvantage had worse psychosocial outcomes, including significantly increased depression, fatigue, and anxiety and decreased peer relationship scores. CONCLUSIONS: Although there were no differences in preoperative PROMIS scores, pediatric patients living in areas with higher levels of socioeconomic deprivation/disadvantage had worse psychosocial PROs after ACLR. LEVEL OF EVIDENCE: Level III-retrospective comparative study.

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.

Screws or Sutures? A Pediatric Cadaveric Study of Tibial Spine Fracture Repairs.

BACKGROUND: Tibial spine fractures are common in the pediatric population because of the biomechanical properties of children's subchondral epiphyseal bone. Most studies in porcine or adult human bone suggest that suture fixation performs better than screw fixation, but these tissues may be poor surrogates for pediatric bone. No previous study has evaluated fixation methods in human pediatric knees. PURPOSE: To quantify the biomechanical properties of 2-screw and 2-suture repair of tibial spine fracture in human pediatric knees. STUDY DESIGN: Controlled laboratory study. METHODS: Cadaveric specimens were randomly assigned to either 2-screw or 2-suture fixation. A standardized Meyers-Mckeever type 3 tibial spine fracture was induced. Screw-fixation fractures were reduced with two 4.0-mm cannulated screws and washers. Suture-fixation fractures were reduced by passing 2 No. 2 FiberWire sutures through the fracture fragment and the base of the anterior cruciate ligament. Sutures were secured through bony tunnels over a 1-cm tibial cortical bridge. Each specimen was mounted at 30° of flexion. A cyclic loading protocol was applied to each specimen, followed by a load-to-failure test. Outcome measures were ultimate failure load, stiffness, and fixation elongation. RESULTS: Twelve matched pediatric cadaveric knees were tested. Repair groups had identical mean (8.3 years) and median (8.5 years) ages and an identical number of samples of each laterality. Ultimate failure load did not significantly differ between screw (mean ± SD, 143.52 ± 41.9 7 N) and suture (135.35 ± 47.94 N) fixations (P = .760). Screws demonstrated increased stiffness and decreased elongation, although neither result was statistically significant at the .05 level (21.79 vs 13.83 N/mm and 5.02 vs 8.46 mm; P = .076 and P = .069, respectively). CONCLUSION: Screw fixation and suture fixation of tibial spine fractures in human pediatric tissue were biomechanically comparable. CLINICAL RELEVANCE: Suture fixations are not biomechanically superior to screw fixations in pediatric bone. Pediatric bone fails at lower loads, and in different modes, compared with adult cadaveric bone and porcine bone. Further investigation into optimal repair is warranted, including techniques that may reduce suture pullout and "cheese-wiring" through softer pediatric bone. This study provides new biomechanical data regarding the properties of different fixation types in pediatric tibial spine fractures to inform clinical management of these injuries.

Quantifying the impact of the coronavirus 2019 pandemic on youth sports-related injuries in the USA.

The purpose of this study was to estimate monthly and annual trends in youth sports-related injury over the years 2016-2020 using the National Electronic Injury Surveillance System (NEISS) database to measure the impact of COVID-19 on overall and sport-specific rates of injury. Children and adolescents (0-19 years) presenting to USA emergency departments with sport participation injury from 2016 to 2020 were identified. Descriptive statistical analyses were performed of injury patterns. An interrupted time series analysis was applied to estimate changes in injury trends during COVID-19. Proportional changes in injury characteristics during this period were examined. An estimated 5 078 490 sports-related injuries were identified with an annual incidence of 1406 injuries per 100 000 population. Seasonal peaks in injuries occurred during September and May. About 58% of injuries were associated with contact sports, such as basketball, football, and soccer, and the most common injuries were sprains and strains. After the pandemic onset, there was a statistically significant 59% decrease in national youth sports-related injuries compared with the average estimates for 2016-2019. While the distribution of injury characteristics did not appear to change, the location of injury appeared to shift away from school toward alternative settings. A significant reduction in youth sports-related injuries was identified in 2020 coinciding with the COVID-19 pandemic, persisting throughout the rest of the year. No changes in the anatomic or demographic distribution of injuries were identified. This study expands our epidemiologic understanding of youth sports-related injury trends and how they changed following the pandemic onset.

Pediatric meniscus morphology varies with age: a cadaveric study.

PURPOSE: In adolescent patients, meniscal tear injury can occur either in isolation (e.g., discoid lateral meniscus tears) or in association with other traumatic injuries including tibial eminence fracture or ACL tear. Damage to meniscal integrity has been shown to increase contact pressure in articular cartilage, increasing risk of early onset osteoarthritis. In symptomatic patients failing conservative management, surgical intervention via meniscus repair or meniscus transplant is indicated. The purpose of this study was to evaluate the radial dimensions of pediatric menisci throughout development. The hypothesis was that the average radial meniscus dimensions will increase as specimen age increases, and mean medial and lateral region measurements will increase at a linear rate. METHODS: Seventy-eight skeletally immature knee cadaver specimens under age 12 years were included in this study. The meniscal specimens were photographed in the axial view with ruler in the plane of the tibial plateau and analyzed using computer-aided design (CAD) software (Autodesk Fusion 360). Measurements were taken from inner to outer meniscus rims at five 45 degree intervals using the clockface as a reference (12:00, 1:30, 3:00, 4:30, 6:00), and total area of meniscus and tibial plateau was recorded. Generalized linear models were used to evaluate the associations of radial width measurements with age, tibial coverage, and lateral vs. medial meniscus widths. RESULTS: All radial width measurements increased significantly with specimen age (p ≤ 0.002), and all lateral-medial meniscal widths increased (p < 0.001). The anterior zones of the meniscus were found to increase at the slowest rate compared to other regions. Tibial plateau coverage was found to not significantly vary with age. CONCLUSIONS: Meniscus radial width and lateral-medial meniscus width are related to age. The anterior width of the meniscus varied least with age. Improved anatomic understanding may help surgeons more effectively plan for meniscus repair, discoid resection/saucerization/repair, and also support appropriate selection of meniscus allograft for transplantation.

Transarticular Versus Retroarticular Drilling of Stable Osteochondritis Dissecans of the Knee: A Prospective Multicenter Randomized Controlled Trial by the ROCK Group.

BACKGROUND: When stable osteochondritis dissecans (OCD) lesions of the femoral condyle in a skeletally immature patient fail to heal with nonoperative methods, the standard of care treatment is condylar OCD drilling. Two primary OCD drilling techniques have been described, but no prospective studies have compared their relative effectiveness. PURPOSE/HYPOTHESIS: The purpose of this study was to compare the healing and function after transarticular drilling (TAD) with that after retroarticular drilling (RAD). It was hypothesized that there would be no difference in rate or time to healing, rate or time to return to sports, patient-reported outcomes (PROs), or secondary OCD-related surgery. STUDY DESIGN: Randomized controlled clinical trial; Level of evidence, 1. METHODS: Skeletally immature patients with magnetic resonance imaging-confirmed stable OCD lesions of the medial femoral condyle who did not demonstrate substantial healing after a minimum of 3 months of nonoperative treatment were prospectively enrolled by 1 of 17 surgeon-investigators at 1 of 14 centers. Patients were randomized to the TAD or RAD group. Tourniquet time, fluoroscopy time, and complications were compared between the treatment groups. Postoperatively, serial radiographs were obtained every 6 weeks to assess healing, and PROs were obtained at 6 months, 12 months, and 24 months. RESULTS: A total of 91 patients were included, consisting of 51 patients in the TAD and 40 patients in the RAD group, who were similar in age, sex distribution, and 2-year PRO response rate. Tourniquet time and fluoroscopy time were significantly shorter with TAD (mean, 38.1 minutes and 0.85 minutes, respectively) than RAD (mean, 48.2 minutes and 1.34 minutes respectively) (P = .02; P = .004). In the RAD group, chondral injury from K-wire passage into the intra-articular space was reported in 9 of 40 (22%) patients, but no associated postoperative clinical sequelae were identified in these patients. No significant differences between groups were detected in follow-up Pediatric-International Knee Documentation Committee, Lysholm, Marx Activity Scale, or Knee injury and Osteoarthritis Outcome Score Quality of Life scores. Healing parameters were superior at 6 months and 12 months in the TAD group, compared with the RAD group, and secondary OCD surgery occurred in 4% of patients who underwent TAD and 10% of patients who underwent RAD (P = .40). Patients in the TAD group returned to sports earlier than those in the RAD group (P = .049). CONCLUSION: TAD showed shorter operative time and fluoroscopy time and superior healing parameters at 6 and 12 months, but no differences were seen in 24-month healing parameters or PROs at all follow-up time points, when compared with RAD. REGISTRATION: NCT01754298 (ClinicalTrials.gov identifier).

Meniscal and Articular Cartilage Predictors of Outcome After Revision ACL Reconstruction: A 6-Year Follow-up Cohort Study.

BACKGROUND: Meniscal and chondral damage is common in the patient undergoing revision anterior cruciate ligament (ACL) reconstruction. PURPOSE: To determine if meniscal and/or articular cartilage pathology at the time of revision ACL surgery significantly influences a patient's outcome at 6-year follow-up. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: Patients undergoing revision ACL reconstruction were prospectively enrolled between 2006 and 2011. Data collection included baseline demographics, surgical technique, pathology, treatment, and scores from 4 validated patient-reported outcome instruments: International Knee Documentation Committee (IKDC), Knee injury and Osteoarthritis Outcome Score (KOOS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and Marx Activity Rating Scale. Patients were followed up at 6 years and asked to complete the identical set of outcome instruments. Regression analysis assessed the meniscal and articular cartilage pathology risk factors for clinical outcomes 6 years after revision ACL reconstruction. RESULTS: An overall 1234 patients were enrolled (716 males, 58%; median age, 26 years). Surgeons reported the pathology at the time of revision surgery in the medial meniscus (45%), lateral meniscus (36%), medial femoral condyle (43%), lateral femoral condyle (29%), medial tibial plateau (11%), lateral tibial plateau (17%), patella (30%), and trochlea (21%). Six-year follow-up was obtained on 79% of the sample (980/1234). Meniscal pathology and articular cartilage pathology (medial femoral condyle, lateral femoral condyle, lateral tibial plateau, trochlea, and patella) were significant drivers of poorer patient-reported outcomes at 6 years (IKDC, KOOS, WOMAC, and Marx). The most consistent factors driving outcomes were having a medial meniscal excision (either before or at the time of revision surgery) and patellofemoral articular cartilage pathology. Six-year Marx activity levels were negatively affected by having either a repair/excision of the medial meniscus (odds ratio range, 1.45-1.72; P≤ .04) or grade 3-4 patellar chondrosis (odds ratio, 1.72; P = .04). Meniscal pathology occurring before the index revision surgery negatively affected scores on all KOOS subscales except for sports/recreation (P < .05). Articular cartilage pathology significantly impaired all KOOS subscale scores (P < .05). Lower baseline outcome scores, higher body mass index, being a smoker, and incurring subsequent surgery all significantly increased the odds of reporting poorer clinical outcomes at 6 years. CONCLUSION: Meniscal and chondral pathology at the time of revision ACL reconstruction has continued significant detrimental effects on patient-reported outcomes at 6 years after revision surgery.

Tibial Spine Fractures in Young Athletes.

Tibial spine fractures are a relatively rare injury in the young athlete. Previously thought to be the equivalent of a "pediatric anterior cruciate ligament (ACL) tear," contemporary understanding of these injuries classifies them as distinct from ACL injuries in this patient population. Successful treatment hinges on accurate diagnosis paying special attention to fracture displacement and the presence of concomitant intraarticular injury. Surgery can be performed using open or arthroscopic techniques and a variety of fixation options. The most common complication after surgical treatment is arthrofibrosis and, therefore, stable fixation is necessary to allow for early, unimpeded knee motion postoperatively.

Distance to the Neurovascular Bundle for Iliotibial Band Graft Passage During Anterior Cruciate Ligament Reconstruction: A Pediatric Cadaveric Study.

Background: The Micheli technique for anterior cruciate ligament (ACL) reconstruction (ACLR) has proven to be a reliable method with a minimal risk for growth disturbance among skeletally immature patients. Purposes: To evaluate the Micheli technique of iliotibial band (ITB) graft passage for ACLR using cadaveric knee models and to measure the distance between the surgical instrument tip and the neurovascular bundle in the posterior knee joint: specifically, the peroneal nerve, tibial nerve, and popliteal artery. Study Design: Descriptive laboratory study. Methods: Gross dissection was performed on 17 pediatric cadaveric knees (12 male and 5 female) aged between 4 and 12 years. To simulate ITB graft passage, we passed a curved-tip hemostat clamp through the posterior capsule, with the knee flexed from 90° to 100°. Next, clinical photographs were taken, and digital imaging software was used to measure the distance in centimeters from the clamp tip to each respective neurovascular structure. Results: The mean distances from the clamp tip to the tibial nerve, popliteal artery, and peroneal nerve were 0.875 cm (range, 0.468-1.737 cm), 0.968 cm (range, 0.312-1.819 cm), and 1.149 cm (range, 0.202-2.409 cm), respectively. Mean values were further calculated for age groups of ≤8, 9-10, and 11-12 years. The mean distance from the clamp tip to the peroneal nerve was 1.400 cm larger for 11- to 12-year-old specimens than for ≤8-year-old specimens (95% CI, 0.6-2.2 cm; P = .005). Conclusion: The neurovascular structures in the posterior knee were in close proximity to the path of graft passage, with distances <1 cm in many specimens in this study. When passing the graft through the knee for an over-the-top position, surgeons should consider these small distances between the path of graft passage and critical neurovascular structures. Clinical Relevance: As the incidence of ACL tears is continuously increasing within the pediatric population, there are a larger number of ACLR procedures being performed. Although neurovascular injuries during ACLR are rare, this study clarifies the close proximity of neurovascular structures during ITB graft passage using the Micheli technique of ACLR.