Juvenile Osteochondritis Dissecans Lesions Research Articles

Complete Radiographic Healing and Related Factors in Juvenile Osteochondritis Dissecans of the Talus

Objectives:Rates of healing following treatment of juvenile osteochondritis dissecans (OCD) of the talus remain scarce. Additionally, there is a paucity of research into the outcomes associated with the treatment of these lesions. The purpose of this study was to evaluate radiographic healing of talar dome OCDs in adolescents.Methods:This was a retrospective review of patients ≤18 years of age with talar OCD from a single pediatric institution within a 12-year period. Charts and radiographs were reviewed for demographics and clinical data, lesion’s location and dimensions, and physeal status. The final radiologic healing was evaluated at 1-year follow-up. Complete and incomplete healing groups were compared using multivariable logistic regression models to examine the predictive effects for the independent variables. A nomogram was produced from the study sample to allow predictions to be made in individual patients.Results:Ninety-two lesions in 74 patients with mean age of 13.1 years (range 7.1 to 18.0 years) were analyzed. 60.8% of the patients were female. Thirty-three (41.8%) lesions were treated conservatively, and 59 (58.2%) were treated surgically (drilling, debridement, microfracture, bone grafting, or loose body removal). Thirty-nine (42.4%) lesions demonstrated complete healing. Patients with complete healing were younger (p 0.032) and had lower BMIs (p 0.006) compared to those with incomplete healing. In a multivariate regression model, the factors that correlated significantly were the age, BMI, Berndt and Harty’s stage at presentation and type of treatment (observation vs. surgical). Location and dimension of the lesion, physeal status (open vs. closed), presenting symptoms, and type of surgical procedure showed no association with likelihood of healing. A nomogram was developed using the independent variables that correlated significantly with the likelihood of complete radiographic healing (Figure 1).Conclusion:Complete radiologic healing of juvenile OCDs was more likely in patients with younger age and lower BMI. Although the difference in outcome between various surgical treatment types was not statistically significant, initial management with surgery was more likely to result in a complete healing compared to observation alone. To our knowledge, this is the first time a nomogram predicting outcome in terms of complete radiographic healing has been developed for juvenile OCD lesions of the talus. Besides its potential role in treatment decision making process, this nomogram can be used to counsel patients and their families with regard to the prognosis for healing.Figure 1.Nomogram for predicting outcome of juvenile osteochondritis dissecans (OCDs) lesion of the talus. To use the nomogram, one should place a straight edge vertically so that it touches the designated variable on the axis for each predictor and then should record the value that each of predictor provides on the “Score”. All of the recorded “points” are then summed, and this value is located on the “total score” line with a straight edge. A vertical line drawn down from the “total score” line to the “Prob” line will identify the probability that the patient will demonstrate healing or progression toward healing after 12 months of treatment.

Juvenile Osteochondritis Dissecans: Cartilage T2 Mapping of Stable Medial Femoral Condyle Lesions.

Purpose To determine whether a T2 mapping sequence could depict early changes in the composition and microstructure of cartilage overlying stable lesions of the medial femoral condyle in patients with juvenile osteochondritis dissecans (JOCD). Materials and Methods This retrospective study analyzed a sagittal T2 mapping sequence performed between September 1, 2015, and March 31, 2017, on 16 patients (10 boys and six girls; median age, 11.5 years) with 18 stable medial femoral condyle JOCD lesions and 18 age-, sex-, and skeletal maturation-matched control participants (11 boys and seven girls; median age, 11.5 years). Cartilage T2 values were quantitatively measured within regions of interest placed around the cartilage within and overlying the JOCD lesion in patients with JOCD and around the cartilage on the weight-bearing medial femoral condyle in patients with JOCD and controls. Wilcoxon signed rank and Wilcoxon rank sum tests were used to compare T2 values. Results T2 values were significantly higher (P < .001) for cartilage within the JOCD lesion than for cartilage overlying the JOCD lesion in patients with JOCD. However, there were no significant differences in T2 values between cartilage overlying the JOCD lesion and cartilage on the weight-bearing medial femoral condyle in patients with JOCD (P = .67) or in T2 values of the cartilage on the weight-bearing medial femoral condyle between patients with JOCD and controls (P = .30). Conclusion There were no significant quantifiable differences in T2 values of cartilage overlying stable JOCD lesions and normal cartilage on the medial femoral condyle, suggesting no substantial changes in cartilage composition and microstructure.

Juvenile Osteochondritis Dissecans of the Trochlea: A Cohort Study of 34 Trochlear Lesions Associated With Sporting Activities That Load the Patellofemoral Joint

Juvenile osteochondritis dissecans (JOCD) lesions are rarely located in the trochlea and few studies have focused on the causes and outcomes of JOCD lesions in this part of the knee. The purpose of this study is to (1) evaluate the clinical characteristics and outcomes of patients who undergo surgery for JOCD in this unusual location as well as (2) assess the association between trochlear JOCD and participation in sporting activities that load the patellofemoral joint. We conducted a retrospective cohort study of 34 trochlear JOCD lesions in 30 patients. Cases that involved traumatic cartilage shear or patella instability were excluded. Preoperative and postoperative magnetic resonance images and x-rays were evaluated and demographic data, sports played, comorbidities, surgical procedures, and clinical data were extracted from medical records. A case-control cohort of 102 femoral condyle lesions was used to assess the correlation between sports played and lesion location. The cohort comprised 34 consecutive trochlear JOCD lesions in 30 patients (26 males, 4 females). Average age at surgery was 13.8 years (9.3 to 18.0 y). In total, 27 (90%) patients were active, and of these active patients, soccer and basketball were the most common sports played. In the case-control comparison, the correlation between playing either basketball or soccer and the presence of a trochlear JOCD lesion was statistically significant (P=0.017). In total, 21 knees (62%) received operative treatment. Sixteen of the surgical patients underwent repair and fixation with bioabsorbable nails. The average length of clinical and radiographic follow-up was 21.1 months. All patients who underwent fixation showed radiographic and/or clinical indications of healing at most recent follow-up. Thirteen of the patients who underwent fixation were active, and all of these patients reported successful return to sports. Thirteen knees underwent nonoperative treatment, and the majority of these patients had limited follow-up. We report a significant association between pediatric athletes who play basketball and soccer and the development of trochlear JOCD, suggesting that repetitive loading of the patellofemoral joint may play a role in the development of JOCD lesions. Patients with trochlear JOCD lesions were likely to undergo surgery, and repair and fixation of the lesions produced good outcomes at short-term follow-up. Level III-case-control study.

Osteochondral Injuries of the Knee in Pediatric Patients.

Osteochondral injuries in pediatric patients may occur as a result of a traumatic injury or secondary to an osteochondritis dissecans (OCD) lesion. Lateral patella dislocation is a common traumatic cause of osteochondral injury that typically occurs at the medial facet of the patella or at the lateral aspect of the distal femur. Multiple theories have been proposed for the cause of an OCD lesion in the knee, including trauma or repetitive microtrauma, local vascular insufficiency, and family history. The most "classic" location for OCD lesions of the knee is the lateral aspect of the medial femoral condyle of the distal femur. Multiple treatment options are available for both traumatic osteochondral injuries and OCD lesions, with important determining factors of treatment being skeletal maturity of the patient, instability of the fragment, lesion location, and size of the lesion. Nonsurgical management is appropriate in some situations. Surgical options range from simple fragment excision to internal fixation of the fracture fragment to more complex cartilage restoration or replacement procedures. This special focus section will discuss the diagnosis and treatment options for traumatic osteochondral knee injuries, including the subset secondary to juvenile OCD lesions.

Juvenile Osteochondritis Dissecans of the Knee: Does Magnetic Resonance Imaging Instability Correlate With the Need for Surgical Intervention?

Background:Several magnetic resonance imaging (MRI) classification systems have been developed to determine the degree of instability of juvenile osteochondritis dissecans (JOCD) lesions. Our current practice involves correlating the patients’ symptoms with their MRI findings, but there are many cases in which this correlation is poor and results in incorrect classification of the stability of a JOCD lesion.Purpose:To determine whether certain MRI findings of JOCD instability are associated with the necessity for arthroscopic intervention to assess lesion stability. A secondary objective was to determine the interobserver agreement of the Kijowski et al (2008) MRI criteria for osteochondritis dissecans (OCD) instability.Study Design:Case series; Level of evidence, 4.Methods:A retrospective review was performed of patients who had documented femoral condyle OCD lesions, had open growth plates, and had been evaluated with serial MRI examinations. Each OCD lesion on MRI was classified according to the Kijowski classification as either stable or likely unstable.Results:The study included 16 patients (17 knees) with 49 MRI examinations. The initial MRI lesion was graded as stable in 59% (10/17), and 7 of these remained stable throughout the study period, with only 1 requiring operative intervention. Two became unstable on MRI, with 1 requiring surgery and 1 reverting back to stable with nonoperative management. The initial MRI lesion was graded as unstable in 41% (7/17) of the knees, with 2 of these becoming stable on MRI during the follow-up period with nonoperative management. The other 5 lesions remained unstable, with 3 eventually requiring surgery. The most important finding in this study was that MRI instability is a poor predictor of the necessity for surgery for JOCD lesions. The correlation between a nonradiologist and a trained musculoskeletal radiologist in the interpretation of the MRI criteria by Kijowski et al showed only substantial agreement for multiple cysts.Conclusion:MRI criteria for OCD instability in the pediatric knee do not always correlate with the necessity for surgery. They are, at times, a helpful adjunct to the management of these patients; however, care must be taken to interpret all available clinical and radiographic information in surgical decision making.

Insights into the Epiphyseal Cartilage Origin and Subsequent Osseous Manifestation of Juvenile Osteochondritis Dissecans with a Modified Clinical MR Imaging Protocol: A Pilot Study.

Purpose To retrospectively determine if a modified clinical magnetic resonance (MR) imaging protocol provides information on the origin of juvenile osteochondritis dissecans (JOCD) lesions and allows for staging on the basis of the proposed natural history of JOCD to better guide clinical management of the disease. Materials and Methods This institutional review board-approved, HIPAA-compliant, retrospective study was performed in 13 consecutive patients (mean age, 14.9 years; age range, 10-22 years; nine male and four female patients) and one additional comparative patient (a 44-year-old man), in which 19 knees with 20 JOCD lesions were imaged. Seventeen lesions occurred in the medial femoral condyle, two occurred in the lateral femoral condyle, and one occurred in the medial trochlea. The clinical 3-T MR imaging protocol was supplemented with a routinely available multiecho gradient-recalled-echo sequence with the shortest attainable echo time of approximately 4 msec (T2* mapping). Results At the earliest manifestation, the lesion was entirely cartilaginous (n = 1). Subsequently, primary cartilaginous lesions within the epiphyseal cartilage developed a rim calcification that originated from normal subjacent bone, which defined a clear cleft between the lesion progeny and the parent bone (n = 9). Secondarily, progeny lesions became ossified (n = 7) while at the same time forming varying degrees of osseous bridging and/or clefting with the parent bone. Two healed lesions with a linear bony scar and one detached lesion were identified. Conclusion The modified MR imaging protocol allowed for identification of the epiphyseal cartilage origin and subsequent stages of ossification in JOCD. The approach allows further elucidation of the natural history of the disease and may better guide clinical management. © RSNA, 2016.

Retrospective Cohort Study of 207 Cases of Osteochondritis Dissecans of the Knee

Objectives:Describe the clinical characteristics, image findings, and outcomes of patients with juvenile osteochondritis dissecans (JOCD) of the knee. To our knowledge, this is the largest single-surgeon cohort of JOCD patients.Methods:Retrospective cohort study of knee JOCD patients assessed by a single pediatric orthopaedic surgeon at a tertiary care center between 2005-2015. All diagnoses were confirmed by magnetic resonance imaging (MRI). Patients with patellar dislocations or osteochondral fractures were excluded. Demographic data, sports played, comorbidities, surgical procedures, and clinical data were extracted from charts. Images were analyzed to identify the location and size of lesions. Chi-square or Fisher’s exact tests were used to compare discrete variables, and Mann-Whitney U and Kruskal Wallis tests to compare continuous variables between groups. P-values of <0.05 were considered significant.Results:Sample consisted of 180 patients (207 knees), 124 boys and 56 girls. Average age at diagnosis was 12.8 years (7.5-17.5). Majority were active in sports (80.8%), primary soccer (36.7%) and basketball (29.4%). JOCD was present bilaterally in 27 patients (15%), 14 knees had bifocal OCD (6.8%), and only 1 patient had bifocal lesions in both knees. Most common location was medial femoral condyle (56.3%) followed by lateral femoral condyle (23.1%), trochlea (11.4%), patella (9%), and tibia (0.5%). In the sagittal view, most common location was the middle third of the condyles (48.7%). Surgery was performed in 72 knees (34.8%), with an average age at surgery of 14.1 years (9.3-18.1). Bilateral JOCD was present in 13 surgical patients (18.8%), but only 3 patients had bilateral surgery. Two operative patients had bifocal JOCD (2.7%) and surgery on both lesions. Location distribution did not differ between surgical and non-surgical lesions. The average normalized area of non-surgical JOCD lesions was 6.8 (0.1-18), whereas surgical lesions averaged a significantly higher area of 7.7 (0.5-17) (p=0.023). Average BMI was 21.6 versus 20.2 for surgical and non-surgical patients, respectively, significantly higher for those who underwent surgery (p=0.002). Most common procedure was fixation with 1.6 mm bioabsorbable nails (54.2%), using an average of 4 nails (1-9). Only 2 cases were fixed using metallic headless screws. Other surgical treatments were drilling (13.9%), microfracture (13.9%), microfracture + fixation (6.9%), removal of loose body/chondroplasty (6.9%), and allograft transplantation (4.2%). Fixation was achieved all-arthroscopic in 43.1% of the cases, and 61.3% of the lesions that were fixed underwent curettage of the subchondral bone. Revision surgery was required in 14 knees (19.4%). The most common revision procedures were microfracture, removal of hardware, chondroplasty and allograft implantation, where some revisions had combined procedures. Most surgical patients had postoperative MRIs (55 knees), with an average radiological follow-up of 14.5 months (range 2.1-55.4).Conclusion:JOCD occurs more frequently in young adolescent athlete boys, affecting the middle third of the medial femoral condyle. In our cohort, 1/3 of the patients had surgery, where bigger lesions and higher BMI were risk factors for operative treatment. At short-term follow up, the success rate following surgery was above 80%.

Non-operative Treatment Outcomes of Stable Juvenile Osteochondritis Dissecans Lesions of the Knee

Objectives:Osteochondritis dissecans (OCD) of the knee most commonly occurs in skeletally-immature pre-adolescent or adolescent patients. Stable juvenile OCD lesions are initially treated via non-operative methods, with varying rates of successful healing reported in the literature. Unloader bracing has been introduced as a relatively new method designed to reduce weight-bearing stress and promote healing for femoral condyle lesions, although the outcomes of unloader bracing compared to other forms of non-operative treatment have not been established.Methods:A retrospective case series was designed to include all patients initially treated non-operatively for stable juvenile OCD of the femoral condyle at a single institution from 2002-2014. Following IRB approval, patient medical records were reviewed for demographic and clinical data, including symptom duration, prior conservative treatment, non-operative treatment modality prescribed and clinical outcome.Results:223 knees of 196 patients (146/196 (74%) male) underwent non-operative treatment for stable OCD of the medial or lateral femoral condyle. Mean age at presentation 11.5 +/- 1.7 years (range 6-16 years). 27/196 patients (14%) were diagnosed with bilateral OCD at presentation, while 169/196 (86%) presented with unilateral OCD. 180/223 knees (81%) were medial femoral condyle lesions, while 39/223 (17%) were lateral femoral condyle lesions and 4/223 (2%) bicondylar. Reported symptom duration was 10.4 +/- 8.8 months (range 0.1 - 38 months). 222/223 (99.6%) knees presented with knee pain, 68/223 (30%) with one or more mechanical symptoms (swelling, giving-way, locking, clicking). 87/223 (39%) had undergone previous non-operative treatment for an average of 2.1 months. On exam at presentation, 130/223 (58%) had tenderness to palpation noted over the associated femoral condyle or ipsilateral joint line. Treatment was based on physician preference. 121/223 (54%) were treated with unloader bracing with activity restriction and physical therapy for a minimum of 3 months, while 102/223 (46%) were treated with other (i.e. “non-unloader”) conservative therapy. In the non-unloader group, all patients were treated with activity restriction with physical therapy and 32% (33/102) had additional non-unloader bracing or immobilization. Treatment of 26/121 (21%) knees in the unloader group included weight-bearing restrictions compared with 30/102 (29%) knees in the non-unloader group. Unloader bracing was associated with healing in 57/121 (47%) knees, while non-unloader treatment led to healing in 60/102 (59%) (p=0.082). Surgical intervention was pursued for 64/121 (53%) knees in the unloader group, at mean 11.0 months after presentation (range 1.9 - 62 months), all of which included OCD drilling and 12/121 (10%) of which included OCD fixation. Subsequent surgical intervention was pursued for 42/102 (41%) knees in the non-unloader group, at mean 6.6 months after presentation (range 0.2 - 40 months), all of which required OCD drilling and 11/102 of which included (11%) OCD fixation.Conclusion:Non-operative treatment for stable OCD of the knee in skeletally-immature patients led to healing in approximately half (52%) of cases. No significant difference was seen between outcomes of patients treated with non-operative methods that included unloader bracing versus non-unloader bracing or other modalities.

Reliability of predictive models for non-operative healing potential of stable juvenile osteochondritis dissecans knee lesions

BackgroundWhile juvenile osteochondritis dissecans (JOCD) lesions have greater healing potential than equivalent lesions in adults, only 50% of JOCD lesions demonstrate radiographic healing after six months of non-operative treatment. Two previous studies have produced nomograms to predict a patient's probability of healing with non-operative treatment based on patient and lesion characteristics. The purpose of this study was to determine inter- and intra-observer reliability of the predictive nomograms. MethodsA consecutive series of 34 skeletally immature patients (40 knees), who underwent non-operative treatment for stable JOCD lesions was retrospectively reviewed. At two time points at least one week apart, two medical students, two orthopaedic surgeons, and a radiologist made measurements of the JOCD lesions. These measurements, along with patient ages and pain type, were used to generate a point value for each lesion based on both nomograms. Intra-class correlations (ICCs) were calculated to determine inter- and intra-rater reliability. ResultsWe found near perfect intra-rater correlation (ICC) for all raters' individual OCD measurements, as well as total point score for the two nomograms (ICC range, 0.780–0.929). Additionally, there was near perfect inter-rater reliability among raters for total scores and individual components of each nomogram (ICC range, 0.721–0.974). ConclusionsThere is high inter- and intra-rater reliability for both point systems for predicting healing of JOCD lesions. Clinicians should be aware of these as tools to help guide decision making in patients with JOCD lesions.

Classification and assessment of juvenile osteochondritis dissecans knee lesions.

Juvenile osteochondritis dissecans (JOCD) knee lesions are common abnormalities in adolescents and children, and have higher rates of spontaneous healing with nonoperative management compared to adult osteochondritis dissecans (OCD) lesions. Multiple classification and assessment systems have been established in order to help clinicians determine which lesions are amenable to nonoperative management. However, these assessments often use adult OCD classification systems of lesion stability, which have poor reliability in JOCD lesions. The purpose of this review is to assess these various classification systems proposed for JOCD lesions. Although arthroscopy remains the gold standard for the definitive assessment of lesion stability, recent evidence suggests that MRI characteristics indicative of instability in adult OCD lesions are not applicable in determining JOCD lesion instability. In addition, the correlation between arthroscopic and MRI indications of instability is highly varied in these younger patients. In order for the pediatric orthopedic surgeon to more accurately predict treatment outcomes in patients with JOCD knee lesions, further investigation into the radiographic characteristics specific to JOCD lesion instability and healing is warranted.

Surgical treatment for osteochondritis dessicans of the knee

Osteochondritis dissecans (OCD) of the knee is a disease of the subchondral bone with secondary injury to the overlying articular cartilage. OCD lesions are generally categorized as juvenile-growth plates open-or adult-growth plates closed. This maturity-based classification scheme has a prognostic value in that many juvenile OCD lesions will heal with conservative care while most symptomatic adult OCD lesions need surgical intervention. OCD can result in pain, knee joint effusions, loose body formation, and arthritis. Short-term treatment goals include pain and symptom resolution while the long-term goal is to minimize arthritis. Surgical options include debridement, drilling, microfracture, reduction and fixation, autograft osteochondral transplantation, autologous chondrocyte implantation, and allograft osteochondreal transplantation.

Current review of juvenile osteochondritis dissecans of the knee

Juvenile osteochondritis dissecans (OCD) is a common source of knee pain in the skeletally immature patient. The etiology of this common lesion is still not agreed upon, but is thought to represent repetitive microtrauma to a focal area in the knee. It can be present anywhere in the knee, but usually is found in the lateral aspect of the medial femoral condyle. It most commonly presents with pain, activity limitation, and occasional swelling. In severe cases, mechanical symptoms may be present as well. Multiple classification systems have been described. Broadly, these lesions can be graded as stable or unstable based on the level of subchondral bone involvement and the integrity of the overlying cartilage. The majority of these lesions can initially be treated nonoperatively. Surgery may be indicated with either progression of symptoms in stable lesions or with unstable lesions. Many operative procedures have shown good results. This review describes the etiology, incidence, diagnosis, imaging modalities, classification, nonoperative, and operative management of juvenile OCD lesions of the knee with a focus on the most recent literature.

Inter- and Intra-Rater Reliability of Predictive Models for the Non-Operative Healing Potential of Stable Juvenile Osteochondritis Dissecans (JOCD) Knee Lesions

Objectives:While juvenile osteochondritis dissecans (JOCD) lesions have greater healing potential than equivalent lesions in adults, only 50% of JOCD lesions demonstrate radiographic healing after 6 months of non-operative treatment. Krause et al. (2013) and Wall et al. (2008) have described models to predict a patient's probability of healing with non-operative treatment based on patient and lesion characteristics. The Wall et al. nomogram incorporates normalized lesion length, normalized lesion width, and pain type, while the Krause et al. model includes normalized lesion width, patient age, and the size of concurrent cyst-like lesions. The purpose of this study was to determine inter- and intra-observer reliability of the predictive nomograms.Methods:We retrospectively evaluated a consecutive series of children with open physes, who underwent non-operative treatment for stable JOCD lesions. Thirty-four patients (40 knees) were included in the study. At two time points at least one week apart, two medical students, two orthopaedic surgeons, and a radiologist made measurements of the JOCD lesions as described by Wall and Krause. These measurements, along with patient ages and pain type, were used to generate a point value for each lesion based on both the Krause and Wall models. Intra-class correlations (ICC) were calculated using the point value data obtained from the nomograms to determine inter- and intra-rater reliability.Results:Based on the Landis & Koch (1977) threshold, we found near perfect intra-rater correlation for all raters in terms of individual OCD measurements, as well as total point score as calculated by both Krause and Wall methods (Table 1). Additionally, amongst the five raters there was near perfect inter-rater reliabilities in total scores, as well as substantial to near perfect reliability in measuring the individual components of the scores (Table 2).Conclusion:There is high inter- and intra-rater reliability for both the Krause and Wall point systems for predicting healing of JOCD lesions. These models appear to be important tools for helping doctors and patients reliably predict the healing potential of non-operative management of JOCD lesions.

Juvenile Osteochondritis Dissecans: Correlation Between Histopathology and MRI.

The objective of our study was to correlate specimens of juvenile osteochondritis dissecans (OCD) lesions of the knee to MRI examinations to elucidate the histopathologic basis of characteristic imaging features. Five children (three boys and two girls; age range, 12-13 years old) who underwent transarticular biopsy of juvenile OCD lesions of the knee were retrospectively included in this study. Two radiologists reviewed the MRI examinations and a pathologist reviewed the histopathologic specimens and recorded characteristic features. Digital specimen photographs were calibrated to the size of the respective MR image with the use of a reference scale. Photographs were rendered semitransparent and over-laid onto the MR image with the location chosen on the basis of the site of the prior biopsy. A total of seven biopsy specimens were included. On MRI, all lesions showed cystlike foci in the subchondral bone, bone marrow edema pattern on proton density-or T2-weighted images, and relatively thick unossified epiphyseal cartilage. In four patients, a laminar signal intensity pattern was seen, and two patients had multiple breaks in the subchondral bone plate. Fibrovascular tissue was found at histopathology in all patients. Cleft spaces near the cartilage-bone interface and were seen in all patients while chondrocyte cloning was present in most cases. Focal bone necrosis and inflammation were infrequent MRI findings. Precise correlation of the MRI appearance to the histopathologic overlays consistently was found. A direct correlation exists between the histopathologic findings and the MRI features in patients with juvenile OCD. Additional studies are needed to correlate these MRI features with juvenile OCD healing success rates.

Prevalence of Bilateral JOCD of the Knee and Associated Risk Factors.

Juvenile osteochondritis dissecans (JOCD) of the knee affects cartilage and subchondral bone surface. Multifocal JOCD is described as multiple lesions within the knee or presence of lesions in other joints. The true prevalence of bilaterality of JOCD is unknown. The purpose of this study is to determine the prevalence of bilateral JOCD and to identify potential risk factors for bilateral disease. We evaluated 108 consecutive patients presenting for JOCD at a single pediatric hospital system. If an OCD lesion of the knee was found, contralateral knee x-rays were performed. Lesion location was documented according to Cahill and Berg, magnetic resonance imaging (MRI) grading documented according to Dipaola, and if surgical treatment was undertaken, intraoperative grading performed according to Guhl. Patients with unilateral JOCD were compared with those with bilateral disease. Statistical analysis of categorical data was performed utilizing likelihood ratio χ test or Fisher exact test and continuous data compared using nonparametric Wilcoxon 2-sample test. There were 85 male (79%) and 23 females (21%) with an average age of 12.3 years (range, 6 to 18 y). Sixty-three percent of lesions were located on the medial femoral condyle and 33% on the lateral femoral condyle. Ninety percent of all lesions were considered weight-bearing lesions. Eighty percent were considered stable on MRI evaluation. Of those lesions that underwent surgical intervention, 61% were either grade I or II lesions. Seventy-three of 108 patients (68%) underwent some form of surgical intervention. Thirty-one patients (29%) were found to have contralateral JOCD lesions. Thirty-nine percent of contralateral lesions found on contralateral radiographs were asymptomatic at presentation and nearly all of those evaluated with MRI (16 of 18) were stable. Sixty-nine percent of contralateral lesions were located on the medial femoral condyle, 27% on the lateral femoral condyle, and 94% were considered weight-bearing lesions. Twelve of 31 contralateral lesions (39%) underwent surgical intervention. Comparing patients with unilateral and bilateral disease, female patients (P<0.05) and younger age at presentation (P<0.009) were risk factors for bilateral JOCD. No statistical difference among other variables was seen with regard to location, MRI or operative stability of lesion, or presence of symptoms. In our consecutive series of 108 patients with JOCD, we found a 29% incidence of bilateral disease. Almost 40% of contralateral lesions were asymptomatic upon presentation. Female sex and younger age at presentation were significant risk factors for bilateral disease. Lesion location, stability, and pain were not statistically significant variables. The authors recommend bilateral radiographic knee evaluation for all patients found to have JOCD. Level IV-retrospective case series.

Intact Bone Vitality and Increased Accumulation of Nonmineralized Bone Matrix in Biopsy Specimens of Juvenile Osteochondritis Dissecans

Background: Although commonly proposed to be the starting point of juvenile osteochondritis dissecans (JOCD), avascular osteonecrosis (AVN) has been an inconsistent finding in histological studies. Analysis of early-stage lesions is required to elucidate the origins of OCD and justify proper treatment. Purpose: To analyze histological sections of JOCD lesions with special emphasis on bone vitality. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Of 64 patients with 74 JOCD lesions (20 females, mean age, 11.4 years; 44 males, mean age, 12.7 years), 34 required surgery because of lesion instability or failed nonoperative treatment. From 9 patients, 11 histological specimens were obtained. Lesions were classified according to the International Cartilage Repair Society (ICRS). Two additional histological control sections were harvested from children without JOCD manifestation. Undecalcified histological sections were histomorphometrically analyzed. To analyze the skeletal health of the patients, biochemical analyses with special emphasis on bone metabolism were performed. Results: Histologically, no osteonecrosis was visible in any of the cases. Osteocyte distribution was similar among OCD lesions and controls. ICRS OCD I lesions (n = 6) showed no intralesional separation. In ICRS OCD II and III lesions (n = 5), there was a subchondral fracture concomitant with histological characteristics of active repair mechanism (increased bone formation: osteoid volume P = .008, osteoblast number P = .046; resorption: osteoclast number P = .005; and tissue fibrosis compared with controls). Instead, in ICRS OCD I lesions, subchondral osteoid volume (P = .010) and osteoblast number (P = .046) were significantly increased compared with controls; however, no active repair mechanisms (no increased bone resorption or fibrous tissue) were detected, suggesting a focal lack of mineralization. Fifty-seven of 64 patients (89.1%) showed a vitamin D deficiency. The median vitamin D serum level of the patients with ICRS OCD I lesions was 13.6 µg/L. Conclusion: In the present study, osteonecrosis was not found in histological specimens of JOCD. As a secondary finding, focal accumulations of nonmineralized bone matrix indicating a lack of mineralization in ICRS OCD I lesions were revealed. This finding correlated with a low level of vitamin D in the affected children.

Functional and radiographic outcomes of unstable juvenile osteochondritis dissecans of the knee treated with lesion fixation using bioabsorbable pins.

The purpose of this study was to evaluate the functional and radiographic outcome of fixation of unstable juvenile osteochondritis dissecans lesions of the knee after a minimum of 2 years of follow-up. A total of 33 unstable juvenile osteochondritis dissecans lesions in 30 patients underwent fixation using bioabsorbable pins through arthrotomy or under arthroscopy. The patients consisted of 23 males and 7 females, and the average age at the time of operation was 14.4 years (range, 11 to 17 y). The functional outcomes were evaluated using the Lysholm score and Hughston's criteria at a mean follow-up of 3.3 years (range, 2.1 to 6.3 y). Healing of the osteochondritis dissecans lesions were confirmed by plain radiographs and magnetic resonance imaging. The Lysholm score improved significantly at 3 months after the surgery, and was maintained until the final follow-up. Radiographically, 32 of 33 lesions healed after fixation of the lesion (healing rate was 97.0%). Healing was achieved at an average of 2.4 months on plain radiographs and 4.2 months on magnetic resonance imaging. According to Hughston's criteria, 25 patients were graded as excellent, 4 as good, and 1 as poor at the final follow-up. The fixation of the unstable juvenile osteochondritis dissecans lesions with bioabsorbable pins demonstrated improved clinical outcomes and radiographic high healing rates at a mean of 3.3 years of follow-up. We advocate this procedure for patients with unstable juvenile osteochondritis dissecans lesions of sufficient quality to enable fixation which will preserve the normal contour of the distal femur. Level IV-retrospective case series.

Management strategies for osteochondritis dissecans of the knee in the skeletally immature athlete.

Osteochondritis dissecans (OCD) is a disorder resulting in focal breakdown of the subchondral bone, with potential disruption of the overlying articular cartilage. The femoral condyles of the knee are the most common locations for OCD, and the incidence of OCD appears to be increasing among active children. Juvenile OCD (JOCD) can be distinguished from adult OCD by the presence of open growth plates. Due to a lack of evidence on its early diagnosis, optimal treatment, and long-term course of healing, JOCD presents a unique challenge for the health care team. Approximately 50% to 67% of stable JOCD lesions heal successfully with nonoperative treatment. For unstable lesions and stable lesions that fail nonoperative treatment, a variety of surgical interventions can be utilized to stimulate bony healing and address articular cartilage lesions. It is recommended that rehabilitation of JOCD be tailored to the individual patient, based on the stage and radiographic status of the lesion and the mode of surgery employed when surgically addressed. Although there is a growing body of literature on this condition, the etiology and optimal methods for treatment, rehabilitation, and evaluating outcomes remain inconclusive due to a lack of quality evidence. Therapy, level 5.

Healing Predictors of Stable Juvenile Osteochondritis Dissecans Knee Lesions After 6 and 12 Months of Nonoperative Treatment

Background: Nonoperative treatment of stable juvenile osteochondritis dissecans (JOCD) lesions of the knee fails in up to 50% of cases. Healing predictors are needed to identify potential failures and thus determine treatment options. Purpose: A predictive model for healing potential after 6 and 12 months of nonoperative treatment of stable JOCD lesions based on sensitive magnetic resonance imagining (MRI) follow-up measurements was developed. Study Design: Cohort study (diagnosis); Level of evidence, 2. Methods: A retrospective cross-sectional study was conducted to analyze 62 white patients (76 stable JOCD lesions) who were initially treated by restriction of activity until they were free of pain. The primary end point was healing investigated on MRI with follow-up measurements after 6 and 12 months of nonoperative treatment. Multivariate logistic regression was used to determine the influence of age, sex, JOCD lesion size, clinical symptoms, and the occurrence of cystlike lesions (CLLs) on healing potential. Additionally, optimal prognostic cutoffs were defined to differentiate failures from nonfailures. Results: After 6 months of nonoperative treatment, 51 (67%) of 76 stable JOCD lesions showed no progression toward healing or showed signs of instability. Normalized lesion width and area and CLL occurrence differed significantly between failures and nonfailures (P < .05). A multivariate logistic regression best-predictors model that included age, CLL size, and normalized lesion width best predicted healing after 6 months and resulted in an area under the curve (AUC) of 0.779 (P < .001). A cutoff at 48% healing probability, as predicted by a nomogram based on age, normalized lesion width, and CLL size, differentiated failures from nonfailures (sensitivity, 60.0%; specificity, 83.7%). After 12 months, 37 lesions (49%) had progressed toward healing, and the sole observation of CLL size had the highest predictive validity (AUC, 0.766). The optimal cutoff was a healing probability of 61% (lesion size, 1.3 mm; sensitivity, 70.3%; specificity, 74.1%). Conclusion: A 6-month period of nonoperative treatment with or without casting might be appropriate if the healing potential is >48%. A 12-month period of nonoperative treatment may be successful if the CLL is <1.3 mm in length as assessed on MRI.

Local Morphological Response of the Distal Femoral Articular–Epiphyseal Cartilage Complex of Young Foals to Surgical Stab Incision and Potential Relevance to Cartilage Injury and Repair in Children

Objective: Describe the local morphological response of the articular–epiphyseal cartilage complex to surgical stab incision in the distal femur of foals, with emphasis on the relationship between growth cartilage injury, enchondral ossification, and repair. Design: Nine foals were induced into general anesthesia at the age of 13 to 15 days. Four full-thickness stab incision defects were created in the cartilage on the lateral aspect of the lateral trochlear ridge of the left distal femur. Follow-up examination was carried out from 1 to 49 days postoperatively, including examination of intact bones, sawed slabs, and histological sections. Results: Incision defects filled with cells displaying fibroblast-, chondrocyte-, and osteoblast-like characteristics, potentially validating the rationale behind the drilling of stable juvenile osteochondritis dissecans lesions in children. Incisions induced necrosis within the cartilage on the margins at all depths of the defects. Sharp dissection may therefore be contraindicated in cartilage repair in young individuals. Incisions caused a focal delay in enchondral ossification in 2 foals, apparently related to the orientation of the incision defect relative to the direction of ossification. Defects became progressively surrounded by subchondral bone, in which granulation tissue containing clasts and foci of osteoblast-like cells was observed. Continued enchondral ossification was therefore likely to result in healing of uncomplicated defects to morphologically normal bone. Conclusions: Epiphyseal growth cartilage injury had the potential to exert a negative effect on enchondral ossification. Enchondral ossification exerted a beneficial effect on repair. This relationship warrants consideration in future studies of cartilage injury and repair within the articular–epiphyseal cartilage complex of all species.