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.

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.

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.

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.

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.

MRI evaluation of pediatric tibial eminence fractures: comparison between conventional and "CT-like" ultrashort echo time (UTE) images.

OBJECTIVE: UTE MRI offers a radiation-free alternative to CT for bone depiction, but data on children is lacking. The purpose of this study was to determine whether UTE images improve detection and characterization of pediatric tibial eminence fractures. METHODS: Fifteen MRIs with UTE from 12 children (10 boys, 2 girls; mean age: 12.6 ± 3.3 years) with tibial eminence fractures (2018-2020) and 15 age-matched MRIs without fractures were included. After randomization, 5 readers reviewed images without and with UTE, at least 1 month apart, and recorded the presence of fracture and preferred images. If fracture is present, radiologists also recorded fragment size, number, and displacement; surgeons assigned Meyers-McKeever grade and management. Disagreements on management were resolved through consensus review. Kappa and intra-class correlation (ICC), sensitivity, and specificity were used to compare agreement between readers and fracture detection between images without and with UTE. RESULTS: For fracture detection, inter-reader agreement was almost perfect (κ-range: 0.91-0.93); sensitivity and specificity were equivalent between images without and with UTE (range: 95-100%). For fracture characterization, UTE improved agreement on size (ICC = 0.88 to 0.93), number (ICC = 0.52 to 0.94), displacement (ICC = 0.74 to 0.86), and grade (ICC = 0.92 to 0.93) but reduced agreement on management (κ = 0.68 to 0.61), leading to a change in consensus management in 20% (3/15). Radiologists were more likely to prefer UTE for fracture and conventional images for non-fracture cases (77% and 77%, respectively, p < 0.001). CONCLUSION: While UTE did not improve diagnosis, it improved agreement on characterization of pediatric tibial eminence fractures, ultimately changing the preferred treatment in 20%.

Early Identification of Arthrofibrosis in Adolescents Following Anterior Cruciate Ligament Reconstruction Is Associated With the Need for Subsequent Surgery: A Matched Case-Control Study.

PURPOSE: To identify the postoperative characteristics associated with the need for subsequent surgical intervention in pediatric anterior cruciate ligament reconstruction (ACLR). METHODS: Patients ≤18 years old who received operative treatment for arthrofibrosis following ACLR versus age- and sex-matched controls with a satisfactory postoperative course were retrospectively reviewed. The range of knee motion preoperatively and at each postoperative visit was recorded. Based on the typical post-operative protocols, visits were categorized into 3 groups: first (first 4 weeks), second (weeks 5-8), and third (weeks 9-16) visits. The deficit in the total arc of range of motion (ROM) in the operative knee relative to the nonoperative knee and the change in ROM between visits were compared. Receiver operating characteristic analysis was performed to determine the time point in which a diagnosis of arthrofibrosis could be predicted with the greatest accuracy. RESULTS: In total, 18 patients with arthrofibrosis (mean age 14.2 ± 2.7 years, 9 male) and 36 control patients were included in the final analysis. Arthrofibrosis patients had significantly larger ROM deficits at all visits, 93° vs 69° for the first, 69° vs 24° for the second, and 56° vs 2º for the third, compared with controls (P < .001 for all). Pairwise comparisons showed that in arthrofibrosis cases, the total ROM did not change significantly between the second and third visits (P = .77), contrary to the controls. Receiver operating characteristic analysis revealed that the total ROM deficit of 50.7° at the second postoperative visit is 89% sensitive and 92.5% specific for development of arthrofibrosis. CONCLUSIONS: We found that patients who go on to need manipulation of the knee under anesthesia/arthroscopic lysis of adhesions do not experience a significant improvement in ROM after the first 5-8 weeks, and that a ROM deficit of >50° at the 5- to 8-week mark postoperatively, is associated with ultimately needing operative intervention for arthrofibrosis. Based on these findings, it may be appropriate to intervene earlier if a patient still has a ROM deficit exceeding 50° by the second postoperative month. LEVEL OF EVIDENCE: Level III, retrospective comparative prognostic trial.

How Much Will My Child's ACL Reconstruction Cost? Availability and Variability of Price Estimates for Anterior Cruciate Ligament Reconstruction in the United States.

BACKGROUND: Despite recent policy efforts to increase price transparency, obtaining estimated prices for surgery remains difficult for most patients and families. PURPOSE: Assess availability and variability of cost and self-pay discounts for pediatric anterior cruciate ligament (ACL) reconstruction in the United States. METHODS: This was a prospective study using scripted telephone calls to obtain price estimates and self-pay discounts for pediatric ACL reconstruction. From July to August 2020, investigators called 102 hospitals, 51 "top-ranked" pediatric orthopaedic hospitals and 51 "non-top ranked" hospitals randomly selected, to impersonate the parent of an uninsured child with a torn ACL. Hospital, surgeon, and anesthesia price estimates, availability of a self-pay discount, and number of calls and days required to obtain price estimates were recorded for each hospital. Hospitals were compared on the basis of ranking, teaching status, and region. RESULTS: Only 31/102 (30.3%) hospitals provided a complete price estimate. Overall, 52.9% of top-ranked hospitals were unable to provide any price information versus 31.4% of non-top-ranked hospitals ( P =0.027). There was a 6.1-fold difference between the lowest and highest complete price estimates (mean estimate $29,590, SD $14,975). The mean complete price estimate for top-ranked hospitals was higher than for non-top-ranked hospitals ($34,901 vs. $25,207; P =0.07). The mean complete price estimate varied significantly across US region ( P =0.014), with the greatest mean complete price in the Northeast ($41,812). Altogether, 38.2% hospitals specified a self-pay discount, but only a fraction disclosed exact dollar or percentage discounts. The mean self-pay discount from top-ranked hospitals was larger than that of non-top-ranked hospitals ($18,305 vs. $9902; P =0.011). An average of 3.1 calls (range 1.0 to 12.0) over 5 days (range 1 to 23) were needed to obtain price estimates. CONCLUSION: Price estimates for pediatric sports medicine procedures can be challenging to obtain, even for the educated consumer. Top-ranked hospitals and hospitals in the Northeast region may charge more than their counterparts. In all areas, self-pay discounts can be substantial if they can be identified but they potentially create an information disadvantage for unaware patients needing to pay out-of-pocket. STUDY DESIGN: Economic; Level of Evidence II. WHAT IS KNOWN ABOUT THE SUBJECT: Previous studies have highlighted the importance of value-based health care decisions and deficits of price transparency in various fields including pediatric and orthopaedics procedures. WHAT THIS STUDY ADDS TO EXISTING KNOWLEDGE: This study is the first to examine availability and variability of health care cost in pediatric sports medicine and the first to assess availability and magnitude of self-pay discounts, setting expectations for the uninsured patient incurring large out-of-pocket expenses.

A Multicenter Comparison of Open Versus Arthroscopic Fixation for Pediatric Tibial Spine Fractures.

BACKGROUND: When operative treatment is indicated, tibial spine fractures can be successfully managed with open or arthroscopic reduction and internal fixation (ARIF). The purpose of the study is to evaluate short-term treatment outcomes of tibial spine fractures in patients treated with both open and arthroscopic fracture reduction. METHODS: We performed an Institutional Review Board (IRB)-approved retrospective cohort study of pediatric tibial spine fractures presenting between January 1, 2000 and January 31, 2019 at 10 institutions. Patients were categorized into 2 cohorts based on treatment: ARIF and open reduction and internal fixation (ORIF). Short-term surgical outcomes, the incidence of concomitant injuries, and surgeon demographics were compared between groups. RESULTS: There were 477 patients with tibial spine fractures who met inclusion criteria, 420 of whom (88.1%) were treated with ARIF, while 57 (11.9%) were treated with ORIF. Average follow-up was 1.12 years. Patients treated with ARIF were more likely to have an identified concomitant injury (41.4%) compared with those treated with ORIF (24.6%, P=0.021). Most concomitant injuries (74.5%) were treated with intervention. The most common treatment complications included arthrofibrosis (6.9% in ARIF patients, 7.0% in ORIF patients, P=1.00) and subsequent anterior cruciate ligament injury (2.1% in ARIF patients and 3.5% in ORIF, P=0.86). The rate of short-term complications, return to the operating room, and failure to return to full range of motion were similar between treatment groups. Twenty surgeons with sports subspecialty training completed 85.0% of ARIF cases; the remaining 15.0% were performed by 12 surgeons without additional sports training. The majority (56.1%) of ORIF cases were completed by 14 surgeons without sports subspecialty training. CONCLUSION: This study demonstrated no difference in outcomes or nonunion following ARIF or ORIF, with a significantly higher rate of concomitant injuries identified in patients treated with ARIF. The majority of identified concomitant injuries were treated with surgical intervention. Extensive surgical evaluation or pretreatment magnetic resonance imaging should be considered in the workup of tibial spine fractures to increase concomitant injury identification. LEVEL OF EVIDENCE: Level III.

Lateral Meniscus Posterior Root Injury: MRI Findings in Children With Anterior Cruciate Ligament Tear.

BACKGROUND. Undiagnosed and unrepaired root tears are increasingly recognized as a preventable cause of accelerated osteoarthritis. Preoperative MRI findings of lateral meniscus posterior root tears in children with concomitant anterior cruciate ligament (ACL) injury are not well described. OBJECTIVE. The purpose of this study was to investigate the performance of preoperative MRI for identifying concomitant lateral meniscus posterior root injuries in pediatric patients with ACL tears with arthroscopy as the reference standard. METHODS. Consecutively registered children who underwent MRI within 90 days before arthroscopic primary ACL reconstruction between March 2017 and December 2019 were included. Two radiologists assessed MRI examinations for direct signs involving the root proper and for findings associated with lateral meniscus posterior root tears. Kappa coefficients for MRI findings were computed. Findings in patients with root tears and intact roots were compared by independent-samples t test, Mann-Whitney U test, chi-square test, Fisher exact test, and multivariable logistic regression analysis. RESULTS. At arthroscopy, 39 children (18 boys, 21 girls; mean age, 15.2 ± 1.4 years) had lateral meniscus posterior root tears; 51 (22 boys, 29 girls; mean age, 15.7 ± 1.8 years) had intact roots. Kappa coefficients ranged from 0.65 to 0.92, aside from tears involving the entheseal segment (κ = 0.55) or popliteomeniscal fascicles (κ = 0.45). MRI findings that were predictors of arthroscopically diagnosed root tear (p < .05) were lateral meniscus root tear in any segment (odds ratio [OR], 16.8; 95% CI, 5.6-50.1), degeneration in any segment (OR, 3.9; 95% CI, 1.6-9.6), coronal cleft sign (OR, 5.7; 95% CI, 2.0-16.7), sagittal ghost sign (OR, 4.8; 95% CI, 1.2-19.1), and axial radial defect sign (OR, 7.1; 95% CI, 2.4-20.5). Tear involving any segment of the root proper had the highest PPV, 82%, with 79% NPV. The coronal cleft, sagittal ghost, and axial radial defect signs had specificities of 88%, 94%, and 88% but sensitivities of 44%, 23%, and 49%. The only significant independent predictor on preoperative MRI was root tear in any segment (OR, 15.8; 95% CI, 2.7-137.5; p = .003). CONCLUSION. Among MRI findings evaluated for preoperative diagnosis of lateral meniscus posterior root tear, tear involving any segment of the root proper had the strongest performance; associated findings had high specificity but low sensitivity. CLINICAL IMPACT. Accurate identification of lateral meniscus posterior root tears on preoperative MRI can aid in operative planning and reduce treatment delay.

MRI Criteria for Meniscal Ramp Lesions of the Knee in Children With Anterior Cruciate Ligament Tears.

OBJECTIVE. The purpose of this study was to investigate the performance of MRI criteria for identifying meniscal ramp lesions in children with concomitant anterior cruciate ligament (ACL) tear, with arthroscopy used as the reference standard. MATERIALS AND METHODS. This retrospective study included 85 children who underwent a preoperative MRI examination and arthroscopically guided primary ACL reconstruction between June 1, 2017, and December 31, 2019. Blinded to arthroscopic findings, two radiologists reviewed all MRI examinations and reached consensus on the presence or absence of an effusion and various findings within the medial and lateral tibiofemoral joints. Chi-square, Fisher exact, independent t, and Mann-Whitney U tests were used to compare MRI findings between patients with and without arthroscopically confirmed meniscal ramp lesions. RESULTS. At arthroscopy, 35 children (23 boys and 12 girls; mean [± SD] age, 15.7 ± 2.0 years) had ramp lesions and 50 children (22 boys and 28 girls; mean age, 15.1 ± 2.4 years) had intact meniscocapsular junctions. Knees in which a ramp lesion was observed were significantly more likely to have MRI findings of a medial meniscus tear (p = .005), peripheral meniscal irregularity (p = .001), junctional T2-weighted signal (p < .001), and a meniscocapsular ligament tear (p < .001). No significant difference was found between children with and without ramp lesions with regard to the presence of an effusion (p = .65) or a lateral meniscus tear (p = .08) or the extent of medial and lateral tibial plateau marrow edema (p = .67 and p = .83, respectively). CONCLUSION. MRI findings associated with an arthroscopic diagnosis of meniscal ramp lesion include medial meniscus tear, peripheral meniscal irregularity, junctional fluidlike signal, and capsular ligament tear.

Magnetic resonance imaging features of intra-articular tenosynovial giant cell tumor in children.

BACKGROUND: Magnetic resonance imaging (MRI) plays a critical role in disease characterization of intra-articular tenosynovial giant cell tumor. OBJECTIVE: To characterize the MRI features of intra-articular tenosynovial giant cell tumor in children with respect to disease subtype and anatomical location. MATERIALS AND METHODS: This retrospective study included children with tenosynovial giant cell tumor who underwent preoperative MRI between January 2006 and May 2020. Two radiologists reviewed each examination to determine disease subtype, signal intensities and the presence of an effusion, osseous changes, chondromalacia, juxtacapsular disease and concomitant joint involvement. Fisher exact, Mann-Whitney U, and Kruskal-Wallis H tests were used to compare findings between subtypes and locations. RESULTS: Twenty-four children (16 girls, 8 boys; mean age: 13.1±3.8 years) with 19 knee and 5 ankle-hindfoot tenosynovial giant cell tumor had either diffuse (n=15) or localized (n=9) disease. An effusion (P=0.004) was significantly more common with diffuse than localized disease. There was no significant difference in MRI signal (P-range: 0.09-1) or other imaging findings (P-range: 0.12-0.67) between subtypes. Children with knee involvement were significantly more likely to present with diffuse disease while those with ankle-hindfoot involvement all presented with focal disease (P=0.004). Juxtacapsular (n=4) and concomitant proximal tibiofibular joint involvement (n=5) were observed with diffuse disease in the knee. Erosions (P=0.01) were significantly more common in the ankle than in the knee. CONCLUSION: In our study, diffuse tenosynovial giant cell tumor was more common than localized disease, particularly in the knee where juxtacapsular and concomitant proximal tibiofibular joint disease can occur.

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.

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.

Anterior Cruciate Ligament Tear Following Operative Treatment of Pediatric Tibial Eminence Fractures in a Multicenter Cohort.

BACKGROUND: Postoperative ipsilateral anterior cruciate ligament (ACL) tears after tibial eminence fracture fixation has been previously noted in the literature. This study aims to describe the prevalence of and risk factors for postoperative ACL tears in a cohort of patients operatively treated for tibial eminence fracture. METHODS: A retrospective review of children undergoing treatment of a tibial eminence fracture at 10 tertiary care children's hospitals was performed. The primary outcome of interest was subsequent ACL rupture. Incidence of ACL tear was recorded for the entire cohort. Patients who sustained a postoperative ACL tear were compared with those without ACL tear and analyzed for demographics and risk factors. A subgroup analysis was performed on patients with a minimum of 2-year follow-up data or those who had met the primary outcome (ACL tear) before 2 years. RESULTS: A total of 385 pediatric patients were reviewed. 2.6% of the cohort experienced a subsequent ACL tear. The median follow-up time was 6.5 months (SD=6.4 mo). Subsequent ACL tears occurred at a median of 10.2 months (SD=19.5 mo) postoperatively. There was a statistically significant association with higher grade tibial spine fractures (Myers and McKeever type III and IV) and subsequent ACL tear (P=0.01). Patients with a subsequent ACL tear were older on average (13.5 vs. 12.2 y old), however, this difference was not statistically significant (P=0.08). Subgroup analysis of 46 patients who had a 2-year follow-up or sustained an ACL tear before 2 years showed a 21.7% incidence of a subsequent ACL tear. There was a statistically significant association with higher grade tibial spine fractures (Myers and McKeever type III and IV) and subsequent ACL rupture (P=0.006) in this subgroup. Postoperative ACL tears occurred in patients who were older at the time that they sustained their original tibial eminence fracture (13.4 vs. 11.3 y old, P=0.035). CONCLUSIONS: Ipsilateral ACL tears following operatively treated pediatric tibial eminence fractures in a large multicenter cohort occurred at a rate of 2.6%. However, in those with at least 2 years of follow-up, the incidence was 21.7%. Subsequent ACL tear was more likely in those with completely displaced (type III or IV) tibial eminence fractures and older patients. LEVEL OF EVIDENCE: Level III-retrospective cohort study.

How Do Race and Insurance Status Affect the Care of Pediatric Anterior Cruciate Ligament Injuries?

OBJECTIVE: To identify associations between race or insurance status and preoperative, intraoperative, and postoperative findings in a large cohort of pediatric anterior cruciate ligament (ACL) reconstructions. DESIGN: Retrospective cohort study. SETTING: Division of Orthopaedics at an urban tertiary care children's hospital. PATIENTS: 915 pediatric (<21) patients undergoing primary ACL reconstruction between January 2009 and May 2016. INDEPENDENT VARIABLES: Insurance status and race. MAIN OUTCOME MEASURES: Delay to surgery, concurrent meniscal injury, sports clearance, postoperative complications, physical therapy, range of motion, and isokinetic strength reduction. RESULTS: Multivariate analysis revealed a significantly longer delay to surgery for black/Hispanic and publicly insured children compared to their counterparts (P = 0.02 and P = 0.001, respectively). Black/Hispanic patients were more likely to sustain irreparable meniscus tears resulting in meniscectomy than white/Asian patients (odds ratio 2.16, 95% confidence interval, 1.10-2.29, P = 0.01). Black/Hispanic and publicly insured children averaged fewer physical therapy (PT) visits (P < 0.001 for both). Nine months after surgery, black/Hispanic patients had significantly greater strength reduction than white/Asian patients. There were no differences in postoperative complications, including graft rupture, contralateral ACL injury, or new meniscus tear along the lines of race, although privately insured patients were more likely to suffer a graft rupture than publicly insured patients (P = 0.006). CONCLUSIONS: After ACL rupture, black/Hispanic children and publicly insured children experience a greater delay to surgery. Black/Hispanic patients have more irreparable meniscus tears and less PT visits. Black/Hispanic patients have greater residual hamstrings and quadriceps weakness 9 months after surgery.

Validated Pediatric Functional Outcomes of All-epiphyseal ACL Reconstructions: Does Reinjury Affect Outcomes?

BACKGROUND: Greater frequency and intensity level of sports participation may be contributing to an increasing incidence of anterior cruciate ligament (ACL) tears in skeletally immature athletes. Prior studies have assessed the functional outcomes of physeal-respecting ACL reconstruction in this patient population based on adult functional outcomes scoring systems; however, there is only sparse literature evaluating functional outcomes of this specific patient population. This study aimed to retrospectively evaluate a cohort of pediatric patients who had undergone all-epiphyseal ACL reconstruction (AEACLR) with a set of clinically validated, pediatric-specific patient-reported functional outcomes scores (PRFOS). We hypothesized that patients who had rerupture would have significantly lower outcomes scores compared with those who did not rerupture. METHODS: This was a retrospective evaluation of AEACLR patients at a single, tertiary care, children's hospital within a period of 2 years and had >6 months of initial clinical postoperative follow-up. Those who consented to participation were provided an online combined survey including questions relating to demographics and rerupture as well as 3 validated pediatric PRFOS. Statistical analysis of the cohort demographics, PRFOS, and subgroup analysis of the rerupture group compared with the ACL intact patients was performed. RESULTS: The mean functional outcome scores at a mean of 48.6 months from surgery demonstrated excellent return to functional activity (Mean International Knee Documentation Committee, 93.8; Pedi-Patient-Reported Outcomes Measurement Information System, 98.8; Pedi- Functional Activity Brief Score, 21.6). There was a 13% rerupture rate and rerupture patients had a significantly decreased Pedi-International Knee Documentation Committee (94.9 intact vs. 86.0 rerupture; P=0.001) and Pedi-Patient-Reported Outcomes Measurement Information System (99.4 intact vs. 95.4 rupture; P=0.001) scores. CONCLUSIONS: AEACLR patients have excellent outcomes based on pediatric-specific PRFOS. Rerupture patients demonstrated a decrease in functional outcomes scores compared with intact ACL patients. The results demonstrate the efficacy of AEACLR as measured by pediatric-specific functional outcome scores for the treatment of ACL rupture in skeletally immature athletes. LEVEL OF EVIDENCE: Level III-retrospective comparative study.