Juvenile Osteochondritis Dissecans Lesions Research Articles

A Screw Length of 14 mm Is Sufficient to Avoid the Physis During Juvenile Osteochondritis Dissecans Lesion Repair but This Can Vary Based on Age and Region of the Distal Femur

A Screw Length of 14 mm Is Sufficient to Avoid the Physis During Juvenile Osteochondritis Dissecans Lesion Repair but This Can Vary Based on Age and Region of the Distal Femur

Hybrid Fixation for Large Unstable Juvenile Osteochondritis Dissecans Lesions: Midterm Results in Adolescent Patients With Completely or Partially Salvageable Progeny Fragment.

This study aimed to describe the midterm clinical and radiographic outcomes of a hybrid fixation technique (HFT) combining interfragmentary compression with screws and biological support provided by the osteochondral autograft transplantation system (OATS) for treating large unstable juvenile osteochondritis dissecans (JOCD) lesions involving the knee in patients aged ≤18 years. Thirteen patients (15 knees, 9 males) with unstable JOCD lesions in the knee underwent treatment. HFT was indicated for lesions that had a completely salvageable (N=10) or partially salvageable progeny fragment (N=5). Patients were evaluated at a minimum follow-up of 1 year. The mean age of the patients was 15.3 years (range, 11 to 18y), with 10 lesions involving the medial femoral condyle and 5 involving the lateral femoral condyle. The mean lesion area were 397.7mm2. The outcome measures included the Pedi-IKDC and Tegner activity scales. Radiographic evaluation consisted of assessing osteochondral graft integration using the MOCART score on MRI and determining the degree of osteoarthritis using the Kellgren-Lawrence system (KL). At a mean follow-up of 51 months (range, 12 to 143mo), the mean Pedi-IKDC and Tegner activity scale were 90.1±7.2 and 94.7±6.7 points, respectively. Patients with unilateral lesions resumed sports activities on average after 7.7 months (range, 6 to 12mo). All patients exhibited progeny fragment integration on MRI, with a mean MOCART score of 85±6.5 (range, 75 to 95). Radiographs indicated grade 1 KL joint space in 13 knees and grade 2 in 2 knees. At the last follow-up, 12 patients were asymptomatic, whereas 1 patient experienced occasional mild discomfort during intense physical activity. Six patients required additional surgery for hardware removal, and 1 patient underwent intra-articular loose body removal. The hybrid fixation technique showed promising outcomes in terms of fragment healing and midterm results for unstable JOCD lesions. These findings suggest that HFT can be considered a valid treatment option for large unstable lesions involving the femoral condyles of the knee in adolescents. Therapeutic study (level of evidence IV).

Juvenile Osteochondritis Dissecans: Current Concepts.

Osteochondritis dissecans (OCD) primarily damages the subchondral bone, leading to damage to the articular cartilage. Juvenile OCD (JOCD) of the knee is limited to skeletally immature and young patients with open growth plates on radiographs. We conducted a review of PubMed articles up until March 16, 2024, using a combination of the following keywords: knee, juvenile, and osteochondritis dissecans. This narrative review included a total of 56 relevant articles that investigated the etiology, incidence, clinical presentation, imaging, classification, and treatment of JOCD of the knee in patients less than 20 years of age. The exact etiology is controversial. Most authors believe that the disease involves multiple theories, such as ischemia, recurrent trauma, and genetic predisposition. Radiographs, the first imaging study in this patient group, cannot determine the stability or instability of the surface cartilage of the OCD lesion. As a result, MRI has become a recommended diagnostic method for determining OCD stability and providing important information for determining a treatment plan. For stable JOCD lesions, nonsurgical treatment is often advised. For unstable and stable lesions that do not respond to nonsurgical treatment, several surgical techniques with good healing rates are available.

Evaluation of lesion and overlying articular cartilage in patients with juvenile osteochondritis dissecans of the knee using quantitative diffusion MRI.

Current clinical MRI of patients with juvenile osteochondritis dissecans (JOCD) is limited by the low reproducibility of lesion instability evaluation and inability to predict which lesions will heal after nonoperative treatment and which will later require surgery. The aim of this study is to verify the ability of apparent diffusion coefficient (ADC) to detect differences in lesion microstructure between different JOCD stages, treatment groups, and healthy, unaffected contralateral knees. Pediatric patients with JOCD received quantitative diffusion MRI between January 2016 and September 2020 in this prospective research study. A disease stage (I-IV) and stability of each JOCD lesion was evaluated. ADCs were calculated in progeny lesion, interface, parent bone, cartilage overlying lesion, control bone, and control cartilage regions. ADC differences were evaluated using linear mixed models with Bonferroni correction. Evaluated were 30 patients (mean age, 13 years; 21 males), with 40 JOCD-affected and 12 healthy knees. Nine patients received surgical treatment after MRI. Negative Spearman rank correlations were found between ADCs and JOCD stage in the progeny lesion (ρ = -0.572; p < 0.001), interface (ρ = -0.324; p = 0.041), and parent bone (ρ = -0.610; p < 0.001), demonstrating the sensitivity of ADC to microstructural differences in lesions at different JOCD stages. We observed a significant increase in the interface ADCs (p = 0.007) between operative (mean [95%CI] = 1.79 [1.56-2.01] × 10-3 mm2 /s)and nonoperative group (1.27 [0.98-1.57] × 10-3 mm2 /s). Quantitative diffusion MRI detects microstructural differences in lesions at different stages of JOCD progression towards healing and reveals differences between patients assigned for operative versus nonoperative treatment.

Physeal fusion status and lesion size are more important than patient age for healing of juvenile osteochodritis dessicans lesions of the distal femur.

The purpose of the study was to evaluate the effect of skeletal age and lesion size, location, and grade on the success of nonoperative treatment for juvenile osteochondritis dissecans (OCD). It is hypothesized that skeletal maturity, including a combination of maturation phenotypes, correlates with nonoperative lesion healing. The clinical and radiographic data on 52 patients aged 7-20years treated for OCD of the distal femur between 2010 and 2019 were retrospectively reviewed. Knee radiographs were assessed for number of lesions present and lesion location, size, and stage. Assessments of skeletal maturation were performed on all antero-posterior knee radiographs using the Roche, Wainer, and Thissen (RWT) method. Patients were categorized as healed if they demonstrated no pain on clinical examination. The relationship between skeletal maturity and nonoperative lesion healing was determined using Spearman rank correlations on available variables. Neither chronological nor skeletal age was associated with surgical status (Rho = 0.03, n.s., and Rho = 0.13, n.s., respectively) or the healing status of nonoperatively treated OCD lesions (Rho = 0.44, n.s., and Rho = 0.03, n.s., respectively). Epiphyseal fusion status of the distal femoral physis was moderately correlated with nonoperative healing, but was not statistically significant (lateral femoral physis: Rho = 0.43, p = 0.05; medial femoral physis: Rho = 0.43, n.s.). Lesion length correlated with surgical status (Rho = -0.38, p = 0.009). The extent of fusion of the distal femoral physis (multi-stage grading) may be more strongly correlated with nonoperative healing than other markers of skeletal maturity or chronological age. Clinicians can use this as an additional radiographic sign when considering nonoperative treatment for juvenile OCD lesions in the distal femur. OCD lesion length and physeal fusion status appear to be more important for healing than patient age.

Age as a Prognostic Factor in Arthroscopic Drilling of Juvenile Osteochondritis Dissecans of the Knee: A National Database Review

Background: Juvenile Osteochondritis Dissecans (JOCD) is a common knee condition that can cause significant morbidity if the lesion does not heal. Arthroscopic drilling is a common surgical treatment for low-grade intact lesions, but its success rate and complications have not been well defined in a large series.Purpose: This study seeks to determine the reoperation rate and the incidence of major complications following arthroscopic drilling of JOCD lesions of the knee.Methods: A query of patients in the Pediatric Health Information System (PHIS) database from 2013 to 2018 was performed for the diagnosis and billing codes specific for arthroscopic drilling of an intact JOCD lesion. Subsequent surgical procedures on ipsilateral and contralateral knees were then analyzed for evidence of additional surgical procedures related to non-healing of the lesion.Results: We identified 1027 patients, 6-17 years of age, who underwent arthroscopic drilling as their initial surgical treatment for a diagnosis of JOCD of the knee. Within 6 months of the original surgery, 27 patients (3%) had a secondary surgery on the ipsilateral knee, and 27 patients (3%) had surgery on the contralateral knee. By 2 years, 84 patients (8%) had a secondary surgery on the ipsilateral knee and 38 patients (4%) had surgery on the contralateral knee. Patient age was a significant factor in both the frequency and distribution of secondary surgeries, with older patients requiring repeat procedures and tending to have more invasive procedures more frequently. Less than 1% of patients underwent another surgical procedure of the knee not specifically to treat the JOCD lesion.Conclusions: The 2-year reoperation rate following drilling of an intact juvenile OCD lesion was 8%. Younger patients (<13 years old) were less likely to undergo a subsequent procedure compared to older patients. In addition, if they did require a second procedure, the majority of older patients required a salvage-type cartilage procedure. The rate of complications requiring additional knee surgeries was less than 1%.Level of Evidence: Level III, Prognostic Study Key Concepts•Arthroscopic drilling in the treatment of juvenile OCD of the knee is very effective, and only 3% of patients require a second surgery in the first 6 months and 8% in the first 2 years.•Younger patients were not as likely to require subsequent arthroscopic drilling for osteochondritis dissecans of the knee.•Intact lesions with low rates of anticipated healing may lead to favorable outcomes if treated sooner.

Poster 200: High Prevalence of Abnormal Imaging Findings in Clinically Asymptomatic Siblings Of JOCD Patients On 3T Knee MRI

Objectives:Endochondral ossification is a skeletal developmental process in children by which the embryonic cartilaginous model of bones undergoes gradual ossification over time until skeletal maturity is reached. Juvenile Osteochondritis Dissecans (JOCD) is a developmental disease characterized by focal areas of chondronecrosis within the epiphyseal cartilage and subsequent delay of the ossification front. JOCD lesions can become loose bodies and lead to premature Osteoarthritis. The etiology of JOCD is not yet well understood, however, there is mounting evidence of a genetic predisposition. Recently, positive familial history, including familial OCD and a genome-wide association study in humans identified genetic loci related to juvenile OCD. In this longitudinal pilot study, we examined siblings of JOCD patients utilizing clinical 3T MRI data to evaluate morphological integrity of the epiphyseal cartilage and the advancing ossification front in the distal femoral condyles in bilateral knees. We hypothesized that asymptomatic, clinically “silent” JOCD lesions could be detected in young siblings of patients affected by JOCD.Methods:In this longitudinal study, 44 MRI datasets from seven skeletally immature participants with no clinical symptoms (7 siblings of JOCD patients; 3 females; 12 bilateral knees; average age at first visit=8.7 years; range=6-10 years) were evaluated. This study was approved by the institutional review board and informed consent was obtained. All images were acquired at 3T MRI system with a 1Tx/15Rx knee coil. Sagittal PD-weighted TSE images without fat suppression (TR/TE = 3900/40 ms, resolution = 0.36x0.36 mm2, scanning time = 1min:49s) and with fat suppression (TR/TE = 3530/40 ms, resolution = 0.36x0.36 mm2, scanning time = 3min:46s) were acquired bilaterally at first visit and at multiple MRI follow-up studies ranging from 6-21 months. The images were reviewed by an experienced musculoskeletal radiologist using the following MRI criteria: (i) integrity of the ossification front; (ii) presence/absence of bone marrow edema; (iii) intact/disrupted secondary physis; and (iv) T2 hyperintensity in epiphyseal cartilage.Results:Five of seven participants (71%) met at least one of the MRI criteria defining a JOCD lesion. Six of the seven participants (86%) had an irregular ossification front at the distal aspect of the medial and/or lateral femoral epicondyles, focal areas of T2 hyperintensities in the epiphyseal cartilage, and a disrupted secondary physis. Of the 13 imaged knees, two knees (both lateral and medial epicondyle) from the same participant and two knees (only lateral epicondyle) had no abnormal MRI findings (= 6 normal epicondyles). Abnormal findings in the medial and lateral epicondyles of the remaining bilateral knees resolved over time in 11 epicondyles (Fig. 1), whereas in the remaining 9 epicondyles the abnormal findings persisted or progressed (Fig. 2).Conclusions:The most important finding of this pilot study is the high prevalence (6 out of 7, 86%) of morphological changes during skeletal development in this group of first-degree relatives of JOCD patients. Furthermore, 71% (5 out of 6) of participants met the imaging criteria for early JOCD lesions at least at one time point during the study without developing any clinical symptoms. There is mounting evidence of a genetic contribution to the etiology of JOCD. In the literature, so called ossification variants are considered morphological variants of bone shape with an overall prevalence of 12% and are believed to resolve naturally over time. While 55% of the epicondyles with abnormalities in the ossification front in our cohort resolved over time on MRI, during the course of this study – typically 8-21 months, the remaining 45% did not resolve or occurred at the last imaging time point with associated marrow edema and needed clinical surveillance. A high incidence of MRI abnormalities in the ossification front, epiphyseal cartilage and secondary physis in a clinically asymptomatic study group of first degree relatives of patients with JOCD supports the hypothesis a) that there is a strong genetic predisposition for this disease, b) clinically “silent” initial stages of the disease could be overlooked, challenging the common current understanding of normal physiologic “ossification variants”.Figure 1.Sagittal PD-weighted TSE w/o fat-suppression (FS) of the lateral femoral condyle in a 10-year-old boy. The follow-up studies demonstrate complete resolution of the irregular ossification front (arrowhead), absence of bone marrow edema.Figure 2.Sagittal PD-weighted TSE w/o fat-suppression (FS) of the lateral femoral condyle in a 10-year-old boy. The baseline study demonstrates a focal T2-hyperintense lesion (arrow) and a delayed ossification front with associated bone marrow edema (*) meeting the MR imaging criteria for an early JOCD lesion. The asymptomatic sibling was clinically surveilled and subsequent follow-up studies demonstrated resolution of the MR imaging findings.

Naturally occurring osteochondrosis latens lesions identified by quantitative and morphological 10.5 T MRI in pigs.

Juvenile osteochondritis dissecans (JOCD) is a pediatric orthopedic disorder that involves the articular-epiphyseal cartilage complex and underlying bone. Clinical disease is often characterized by the presence of radiographically apparent osteochondral flaps and fragments. The existence of early JOCD lesions (osteochondrosis latens [OCL] and osteochondrosis manifesta [OCM]) that precede the development of osteochondral flaps and fragments is also well recognized. However, identification of naturally occurring OCL lesions (confined to cartilage) using noninvasive imaging techniques has not yet been accomplished. We hypothesized that 10.5 T magnetic resonance imaging(MRI) can identify naturally occurring OCL lesions at predilection sites in intact joints of juvenile pigs. Unilateral elbows and knees (stifles) were harvested from three pigs aged 4, 8, and 12 weeks, and scanned in a 10.5 T MRI to obtain morphological 3D DESS images, and quantitative T2 and T1ρ relaxation time maps. Areas with increased T2 and T1ρ relaxation times in the articular-epiphyseal cartilage complex were identified in 1/3 distal femora and 3/3 distal humeri and were considered suspicious for OCL or OCM lesions. Histological assessment confirmed the presence of OCL or OCM lesions at each of these sites and failed to identify additional lesions. Histological findings included necrotic vascular profiles associated with areas of chondronecrosis either confined to the epiphyseal cartilage (OCL, 4- and 8-week-old specimens) or resulting in a delay in endochondral ossification (OCM, 12-week-old specimen). Future studies with clinical MR systems (≤7 T) are needed to determine whether these MRI methods are suitable for the in vivo diagnosis of early JOCD lesions in humans.

Longitudinal 3T MRI T2 * mapping of Juvenile osteochondritis dissecans (JOCD) lesions differentiates operative from non-operative patients-Pilot study.

Juvenile osteochondritis dissecans (JOCD) is an orthopedic joint disorder of children and adolescents that can lead to premature osteoarthritis. Thirteen patients (mean age: 12.3 years, 4 females), 15 JOCD-affected and five contralateral healthy knees, that had a baseline and a follow-up magnetic resonance imaging (MRI) (mean interval of 8.9 months) and were treated nonoperatively during this interval were included. Retrospectively, patients were assigned to operative or nonoperative groups based on their electronic medical records. Volumetric mean T2 * values were calculated within regions of interest (progeny lesion, interface, parent bone) and region matched control bone in healthy contralateral knees and condyles. The normalized percentage difference of T2 * between baseline and follow up MRI in nonoperative patients significantly increased in progeny lesion (-47.8%, p < 0.001), parent bone (-13.9%, p < 0.001), and interface (-32.3%, p = 0.011), whereas the differences in operative patients were nonsignificant and below 11%. In nonoperative patients, the progeny lesion (p < 0.001) and interface T2 * values (p = 0.012) were significantly higher than control bone T2 * at baseline, but not at follow-up (p = 0.219, p = 1.000, respectively). In operative patients, the progeny lesion and interface T2 * values remained significantly elevated compared to the control bone both at baseline (p < 0.001, p < 0.001) and follow-up (p < 0.001, p < 0.001), respectively. Clinical Significance: Longitudinal T2 * mapping differentiated nonhealing from healing JOCD lesions following initial nonoperative treatment, which may assist in prognosis and improve the ability of surgeons to make recommendations regarding operative versus nonoperative treatment.

The "hump" a new arthroscopic phenomenon guiding for reliable therapy of osteochondritis dissecans of variable stability status.

Despite 150years of research, there are currently no reliable morphological characteristics that can be used to differentiate between stable and unstable juvenile osteochondritis dissecans (JOCD) lesions in the knee joint. Arthroscopic probing is still the gold standard. In arthroscopic evaluation, a previously undescribed pattern of a cartilaginous convex elevation ("hump") was identified as a new feature and potential sign of JOCD in transition to instability. The aim of the study was to evaluate the clinical outcomes after surgical intervention (drilling) on the "hump". In a retrospective case series of sixteen patients with an arthroscopically detectable "hump", the analysis of clinical function scores (Lysholm, Tegner) and morphological MRI monitoring of radiological healing were performed. The assessment of lesion healing was based on pre- and postoperative MRI examinations. The "hump" was defined as an arthroscopically impressive protrusion of the femoral articular surface with a minimally softened, discolored, but intact cartilage margin that, is not mobile upon in the arthroscopic palpation hook test. The primary therapy of choice was drilling of all "humps". The "hump" could be detected arthroscopically in 16 of 59 JOCD lesions. Specific MRI correlations with the "hump" or arthroscopic unstable lesions could not be detected. Not all "humps" showed signs of MRI-based healing after the drilling, and in some a dissection of the osteochondral flap occurred within the first postoperative year. As a result, secondary refixation became necessary. In the present study, the "hump" was identified as an important differential diagnostic arthroscopic feature of an arthroscopically primarily stable JOCD lesion, potentially placing the lesion at risk of secondary loosening over time. Therefore, drilling alone may not be appropriate in the event of arthroscopic "hump" discovery, but additional fixation may be required to achieve the healing of the lesion. III.

Compositional evaluation of lesion and parent bone in patients with juvenile osteochondritis dissecans of the knee using T2 * mapping.

Juvenile osteochondritis dissecans (JOCD) lesions contain cartilaginous, fibrous and osseous tissues which are difficult to distinguish with clinical, morphological magnetic resonance imaging (MRI). Quantitative T2 * mapping has earlier been used to evaluate microstructure and composition of all aforementioned tissues as well as bone mineral density. However, the ability of T2 * mapping to detect changes in tissue composition between different JOCD lesion regions, different disease stages, and between stable and unstable lesions has not been demonstrated. This study analyzed morphological and T2 * MRI data from 25 patients (median age, 12.1 years) with 34 JOCD-affected and 13 healthy knees. Each lesion was assigned a stage reflecting the natural history of JOCD, with stages I and IV representing early and healed lesion, respectively. T2 * values were evaluated within the progeny lesion, interface and parent bone of each lesion and in the control bone region. T2 * was negatively correlated with JOCD stage in progeny lesion (ρ = -0.871; p < 0.001) and interface regions (ρ = -0.649; p < 0.001). Stage IV progeny showed significantly lower T2 * than control bone (p = 0.028). T2 * was significantly lower in parent bone than in control bone of patients with stable lesions (p = 0.009), but not in patients with unstable lesions (p = 0.14). Clinical significance: T2 * mapping enables differentiation between different stages of JOCD and quantitative measurement of the ossification degree in progeny lesion and interface. The observed T2 * decrease in healed and stable lesions may indicate increased bone density as a result of the active repair process. T2 * mapping provides quantitative information about JOCD lesion composition.

Comparison of Weightbearing and Nonweightbearing Juvenile Osteochondritis Dissecans Lesions of the Lateral Femoral Condyle.

Background:Repetitive microtrauma may contribute to osteochondritis dissecans (OCD) lesions of the femoral condyle. The effect of differential loading between OCD weightbearing (WB) zones has not been studied.Purpose:To determine whether clinical and radiographic variables differ by WB zone in lateral femoral condyle OCD lesions.Study Design:Cohort study; Level of evidence, 3.Methods:We retrospectively reviewed a consecutive series of patients aged <18 years with lateral femoral condyle OCD lesions presenting at a single institution between 2004 and 2018. Patients with OCD lesions outside of the lateral femoral condyle were excluded. Lesions were localized on radiographs using the Cahill and Berg classification, referencing the Blumensaat line and an extension of the posterior femoral cortex. Progeny bone characteristics evaluated at baseline and 24-month follow-up included ossification, distinct borders from parent bone, and displacement. Baseline lesion dimensions were measured on magnetic resonance imaging (MRI) scans. We evaluated posttreatment pain level, return-to-activity rate, and patient-reported outcome measures (PROMs) including the Pediatric International Knee Documentation Committee score, Knee injury and Osteoarthritis Outcome Score, and Pediatric Functional Activity Brief Scale.Results:A total of 62 lateral femoral condyle OCD lesions (mean follow-up, 24.1 months) presented within the study period: 26 WB lesions and 36 nonweightbearing (NWB) lesions. At presentation, no differences between the lesion types were observed in symptom chronicity or symptomatology. NWB lesions were deeper on MRI scans (sagittal depth, 7.11 vs 5.96 mm; P = .046; coronal depth ratio, 0.05 vs 0.01 mm; P = .003), were more likely to develop progeny bone (69.4% vs 44%; P = .047), and demonstrated higher radiographic healing rates (52.8% vs 24%; P = .025) compared with WB lesions. PROMs at follow-up were available for 25 of 62 patients (40.3%), with no statistically significant differences between cohorts at any time. Return to full activity was observed in 72% of WB and 82.1% of NWB lesions (P = .378).Conclusion:Lateral femoral condyle OCD lesions of the knee in WB and NWB zones presented similarly at initial evaluation; however, NWB lesions demonstrated higher rates of progeny bone formation and radiographic healing at mean 2-year follow-up.

Ankle Morphology and Juvenile Osteochondritis Dissecans (JOCD) of the Talus: Is There an Association? An MRI Study.

Factors that contribute to the development of juvenile osteochondritis dissecans (JOCD) of the talus are poorly understood. Some authors suggest that a higher loading of the affected zone may be a cofactor in osteochondral lesions. Therefore, the purpose of the study is to evaluate any association between ankle morphology and talus JOCD using morphologic parameters from magnetic resonance images. Our hypothesis is that ankles with JOCD lesions would have differences in the anatomy compared with age and sex-matched unaffected ankles. We evaluated a total of 75 extremities. There were 22 patients (25 ankles) with talus JOCD lesions, and 50 patients (50 ankles) sex and age-matched individuals with healthy ankles served as controls. Two examiners conducted independent measurements of 8 magnetic resonance images parameters: tibial anterior surface angle, tibial shaft both malleoli angle (TBM), tibial axis-medial malleolus angle, anterior opening angle of the talus, malleolar width, tibial lateral surface angle, Maximal tibial thickness, length of trochlea tali arc, and height of trochlea tali arc. Measurement reliability was assessed using intraclass correlation coefficients. Differences in parameters between JOCD patients and controls were evaluated using independent t test. The level of significance was taken to be P<0.05. Intraclass correlation coefficients demonstrated good to excellent consistency for all measurements. Sagittal parameters demonstrated a significant length of trochlea tali arc increase in ankles with JOCD lesions compared with normal ankles (P=0.015). There was no statistical difference in any of the axial or coronal parameters. Ankle morphology may have a relationship with JOCD lesions. Future larger studies will be useful for further clarifying our findings, and detecting other potential predisposing factors with clinical relevance and how they can be modified. Cross-sectional study (Level of evidence III).

Treatment of Juvenile Knee Osteochondritis Dissecans with a Cell-Free Biomimetic Osteochondral Scaffold: Clinical and MRI Results at Mid-Term Follow-up.

Osteochondral surgical procedures have been described for the treatment of unfixable osteochondritis dissecans (OCD), but only few of them have been studied for juvenile OCD (JOCD) lesions. A cell-free biomimetic osteochondral scaffold showed positive results in adult patients. The aim of this study was to evaluate the results of this scaffold for the treatment of knee JOCD at mid-term follow-up. Twenty patients (14 males, 6 females) were included in this study. Mean age was 16.2 ± 1.4 years, average defect size was 3.2 ± 1.8 cm2, and mean symptoms duration was 20.2 ± 17.9 months. After the implantation of the osteochondral collagen-hydroxyapatite scaffold (Maioregen, Fin-Ceramica, Faenza, Italy), patients were evaluated preoperatively and prospectively at 1, 2, and at final mean follow-up of 6 years (range 5-7 years) with International Knee Documentation Committee (IKDC) subjective and objective, Tegner, and EuroQol visual analogue scale (VAS) scores. MRI evaluation was performed with the MOCART 2.0 score. All scores showed a significant improvement. IKDC subjective score went from 50.3 ± 17.4 preoperative score to 75.3 ± 14.6 at 1 year (P = 0.002), 80.8 ± 14.6 at 2 years and 85.0 ± 9.3 at 6 years. The Tegner score improved from the preoperative evaluation of 2.6 ± 1.4 to 5.5 ± 2.0 at 6 years (P < 0.0005), although without reaching the level registered before the onset of symptoms. A longer symptoms duration influenced negatively IKDC subjective and Tegner scores up to 2 years (P = 0.003 and P = 0.002, respectively) but did not affect the final outcome. Lesion size did not affect the final result. The MOCART 2.0 score showed a significant improvement between 1-year and final follow-up, but with persisting subchondral alterations. This study demonstrated a clinical improvement stable over time with a high survival rate, although with persisting abnormal MRI findings, especially at subchondral bone level. This procedure can be considered a suitable option for the treatment of young patients affected by knee OCD. Level of evidence. Case series, level IV.

Conservative Management and Serial Magnetic Resonance Imaging in an Athlete with Radiographically Unstable Juvenile Osteochondritis Dissecans of the Knee: Case Report

This report describes a case of radiographically unstable knee juvenile osteochondritis dissecans (JOCD) that healed without surgery. The authors utilize objective measurements of serial magnetic resonance imaging (MRI) to evaluate healing of the JOCD lesion and inform the decision to continue the course of conservative care or proceed to surgery. A 15-year-old soccer player presented with a 1-month history of worsening left knee pain. Magnetic resonance imaging showed an osteochondral lesion of the lateral femoral condyle with highly specific signs of instability including multiple cyst-like lesions (CLL) and large CLL diameter. An approach involving low-impact, low-intensity rehabilitative exercises and other modalities was implemented. Follow-up MRIs were performed at 3, 6, and 8 months to monitor changes and recalculate healing probability using a previously published nomogram. Clinical improvement was measured using outcome assessments. Follow-up MRIs showed a progressive reduction in size and number of CLLs and a resulting increase in healing probability from 20 to 70%. The patient successfully returned to play at just over 8 months after diagnosis. This case highlights that significant healing in knee JOCD is possible during a carefully monitored course of non-operative care, despite imaging signs of instability such as multiple and large CLL.

MRI evaluation of articular cartilage in patients with juvenile osteochondritis dissecans (JOCD) using T2∗ mapping at 3T

Evaluate articular cartilage by magnetic resonance imaging (MRI) T2∗ mapping within the distal femur and proximal tibia in adolescents with juvenile osteochondritis dissecans (JOCD). JOCD imaging studies acquired between August 2011 and February 2019 with clinical and T2∗ mapping MRI knee images were retrospectively collected and analyzed for 31 participants (9F/22M, 15.0±3.8 years old) with JOCD lesions in the medial femoral condyle (MFC). In total, N=32 knees with JOCD lesions and N=14 control knees were assessed. Mean T2∗ values in four articular cartilage regions-of-interest (MFC, lateral femoral condyle (LFC), medial tibia (MT), and lateral tibia (LT)) and lesion volume were measured and analyzed using Wilcoxon-rank-sum tests and Spearman correlation coefficients (R). Mean±standard error T2∗ differences observed between the lesion-sided MFC and the LFC in JOCD-affected knees (28.5±0.9 95% confidence interval [26.8, 30.3] vs 26.3±0.7 [24.8, 27.7] ms, P=0.088) and between the affected- and control-knee MFC (28.5±0.9 [26.8, 30.3] vs 28.5±0.6 [27.1, 29.9] ms, P=0.719) were nonsignificant. T2∗ was significantly increased in the lesion-sided MT vs the LT for the JOCD-affected knees (21.5±0.7 [20.1, 22.9] vs 18.0±0.7 [16.5, 19.5] ms, P=0.002), but this same difference was also observed between the MT and LT in control knees (21.0±0.6 [19.7, 22.3] vs 18.1±1.1 [15.8, 20.4] ms, P=0.037). There was no significant T2∗ difference between the affected- and control-knee MT (21.5±0.7 [20.1, 22.9] vs 21.0±0.6 [19.7, 22.3] ms, P=0.905). T2∗ within the lesion-sided MFC was not correlated with patient age (R=0.20, P=0.28) or lesion volume (R=0.06, P=0.75). T2∗ values were slightly increased near lesions in later-stage JOCD subjects but without statistical significance. T2∗ relaxations times were not significantly different from control sites in the articular cartilage overlying JOCD lesions in the MFC or adjacent MT cartilage in early-stage JOCD.

Arthroscopic Fixation of Osteochondritis Dissecans of the Knee Using a Motorized Pick and Headless Compression Screws

Osteochondritis dissecans (OCD) of the knee affects children and adolescents. The condition is characterized by sterile osteonecrosis of the subchondral bone. The cause is unknown. OCD is divided into juvenile or adult type, depending on whether the physis is open or closed at the time of diagnosis. Stable juvenile OCD lesions have substantial healing potential and are treated conservatively, with a healing potential of up to 75%. However, in unstable lesions and in all symptomatic adult OCD lesions, surgical treatment is indicated. The purpose of this article was to present our method of arthroscopic fixation of an unstable OCD in the knee, using a motorized pick to stimulate the bed of the lesion, and firm fixation with headless screws. The advantage of this method is the controlled and meticulous debridement and stimulation of the sclerotic necrosis behind the OCD fragment and the firm compression achieved with the screws, enabling an intensive and early rehabilitation.

Juvenile Osteochondritis Dissecans (JOCD) Retroarticular Drilling: Position Assessment Technique

Juvenile osteochondritis dissecans (JOCD) is an acquired condition of the joint that affects the articular surface and the subchondral bone in skeletally immature patients. Retroarticular drilling is an accepted option for stable knee JOCD when conservative treatment fails. The primary limitation of this technique is the requirement for fluoroscopy and its associated radiation. Intraoperative fluoroscopy can be a challenge because of the superimposed radiographic density of the musculoskeletal structures that may obscure visualization of the lesion in the lateral view. Consequently, most surgeries require multiple shots for the identification of the lesion and Kirschner-wire placement. We describe a new location assessment system that can, therefore, allow surgeons to more accurately identify the JOCD lesion during retroarticular drilling using radiographic landmarks. This technique may help avoid excessive intraoperative radiation and expedite intervention during the retroarticular drilling of osteochondritis dissecans lesions.

Clinical Value of MRI in Assessing the Stability of Osteochondritis Dissecans Lesions: A Systematic Review and Meta-Analysis.

OBJECTIVE. The purpose of this study is to perform a systematic review and meta-analysis to estimate the clinical value of MRI in assessing the stability of osteochondritis dissecans (OCD) lesions. MATERIALS AND METHODS. A systematic review of the literature published from January 1995 to July 2018 was performed by two independent reviewers using predefined search terms. The reference standard was established as arthroscopy or open surgery. True- and false-positive results as well as true- and false-negative results were counted. The quality of the selected studies was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 tool. Pooling of diagnostic accuracy, subgroup analysis, and identification of publication bias were included. RESULTS. Sixteen studies were included in the general data pooling. The pooled sensitivity and specificity were 0.92 (95% CI, 0.87-0.95; I2 = 0.55) and 0.85 (95% CI, 0.64-0.95; I2 = 0.88), respectively. The pooled sensitivity and specificity for juvenile OCD lesions were 0.93 (95% CI, 0.82-0.97) and 0.68 (95% CI, 0.41-0.86), respectively. Subgroup analysis showed that the staging system of Dipaola and colleagues and the criteria of De Smet and colleagues had a significant independent association with sensitivity. There was no evidence of publication bias (p = 0.57). CONCLUSION. The current meta-analysis suggested that MRI has a high diagnostic value for assessing the stability of OCD lesions. However, the MRI criteria applied for adult OCD lesions do not perform well in predicting stability of juvenile OCD lesions. Although some new juvenile OCD-specific MRI criteria yielding a satisfactory outcome have been proposed, further investigations are warranted.

Limitation of in-situ arthroscopic fixation for stable juvenile osteochondritis dissecans in the knee.

Level IV, case series.