Osteochondritis dissecans is a focal, acquired alteration of subchondral bone with risk for instability and disruption of adjacent articular cartilage, most commonly affecting the knee (lateral aspect of the medial femoral condyle) in preadolescent and adolescent athletes aged 10–20 years. [1-2] It may lead to premature osteoarthritis if untreated. [3] The overall annual incidence is approximately 6–29 per 100,000, with a 2–4× higher incidence in males; the highest rates occur in males aged 11–15 years. [4-6] Incidence appears to be increasing, likely related to earlier and more competitive sports participation. [6-7]
1. History
- Knee pain is the most common presenting symptom — typically vague, poorly localized, activity-related, and insidious in onset [1][8-9]
- Characterize timing: gradual onset vs. acute worsening; duration of symptoms; relationship to weight-bearing and impact activities
- Ask about mechanical symptoms: locking, catching, popping, giving way — these suggest an unstable lesion or loose body [8][10]
- Assess for effusion (swelling after activity), stiffness, and decreased range of motion [1][9]
- Determine activity level: sport type, frequency, intensity, recent changes in training volume [11-12]
- Important negatives: absence of acute traumatic event (OCD differs from traumatic osteochondral fractures); no systemic symptoms (fever, weight loss) [2]
- Ask about bilateral symptoms — nearly one-third of patients present with bilateral lesions [1]
2. Alarm Features
- Mechanical symptoms (locking, catching) — indicate unstable fragment or loose body requiring urgent orthopedic evaluation [8][10]
- Acute loss of range of motion — suggests fragment displacement [1]
- Significant effusion — clinical risk factor for lesion instability [1]
- Age ≥14 years with symptoms — higher risk of instability and poorer nonoperative outcomes [1]
- Closing or closed physes — reduced healing potential, more likely to require surgery [2][7]
- Rapidly progressive symptoms despite activity modification
3. Medications
- NSAIDs (ibuprofen, naproxen): first-line for pain and inflammation management during conservative treatment
- Acetaminophen: alternative analgesic
- No specific pharmacologic therapy targets OCD healing
- Avoid corticosteroid injections into the affected joint — may impair cartilage and subchondral bone healing
- Consider vitamin D and calcium optimization, particularly in adolescents with nutritional deficiencies, given the role of bone health in healing [2]
4. Diet
- Ensure adequate calcium and vitamin D intake for bone health, especially in adolescent athletes
- Nutritional factors have been theorized as potential contributors to OCD etiology [2]
- Obesity is a recognized contributor — weight management may reduce mechanical overload on the joint [2]
- No specific dietary triggers or restrictions are established for OCD
5. Review of Systems
- Musculoskeletal: pain in other joints (elbow, ankle — other common OCD sites), bilateral knee symptoms, hip or back pain
- Constitutional: growth and development history, pubertal stage (relevant to physeal status)
- Endocrine: menstrual history in females (relative energy deficiency in sport / RED-S)
- Rheumatologic: morning stiffness, rash, eye symptoms (to exclude inflammatory arthropathy)
- Hematologic: easy bruising, bleeding (to exclude coagulopathy if effusion is present)
6. Collateral History and Family History
- Family history of OCD — genetic predisposition has been theorized [3-4]
- Family history of growth disorders, skeletal dysplasias, or early-onset osteoarthritis
- Sports participation history from parents/coaches — volume, intensity, year-round single-sport specialization [11]
- Social context: competitive pressure, training demands, willingness to comply with activity restriction
7. Risk Factors
- Age 10–20 years (peak 11–15 years) [4-5]
- Male sex (3–4× higher risk) [5-6]
- High-impact sports participation — basketball (most common in males), soccer (most common in females) [12-13]
- Repetitive microtrauma and mechanical overload [3][11]
- Limb malalignment: varus alignment associated with medial femoral condyle OCD; valgus with lateral femoral condyle OCD [13]
- Obesity and nutritional deficiencies [2]
- Smoking (in older adolescents/young adults) — predictive of lesion instability [13]
- Black race may have higher odds of OCD [5]
8. Differential Diagnosis
- Meniscal tear — mechanical symptoms, joint line tenderness; MRI distinguishes
- ACL/ligamentous injury — usually acute traumatic mechanism, instability on exam
- Patellofemoral pain syndrome — anterior knee pain, no radiographic lesion
- Patellar subluxation/dislocation — lateral patellar apprehension, effusion
- Avascular necrosis (AVN) — overlapping imaging features but different etiology (systemic risk factors such as corticosteroids, alcohol) [14]
- Stress fracture — localized bony tenderness, MRI shows edema pattern without focal subchondral lesion
- Normal ossification variant / accessory ossification center — can mimic OCD on radiographs in younger children; MRI helps differentiate [1]
- Osteochondral fracture — acute traumatic mechanism, distinct from the insidious onset of OCD [2]
- Bone tumor (osteoid osteoma, osteochondroma) — night pain, different imaging appearance
- Referred hip pathology (SCFE, Legg-Calvé-Perthes) — always examine the hip in a child with knee pain
9. Past Medical History
- Previous episodes of knee pain, swelling, or mechanical symptoms
- Prior OCD diagnosis (same or contralateral knee, or other joints)
- History of growth disorders or skeletal dysplasia [4]
- Previous knee surgery or trauma
- Chronic conditions affecting bone health (vitamin D deficiency, endocrine disorders)
- History of early sports specialization or overtraining [11]
10. Physical Exam
- Gait: may be normal, antalgic, or externally rotated (compensatory to avoid tibial eminence impingement on lesion) [2][8]
- Effusion: assess with ballottement or sweep test — presence is a risk factor for instability [1]
- Point tenderness: may be palpable over the medial femoral condyle with the knee flexed [8]
- Range of motion: assess for any loss — a risk factor for instability [1]
- Wilson test: internally rotate the tibia during knee extension from 90° to 30° flexion — pain that is relieved by external rotation is positive; however, sensitivity is low (~25%), so a negative test does not exclude OCD [2][15]
- Crepitus with range of motion
- Assess for quadriceps atrophy (chronic cases)
- Examine the contralateral knee — bilateral disease in up to one-third of cases [1]
- Examine the hip — to exclude referred pain (especially in pediatric patients)
11. Lab Studies
- No specific laboratory tests are diagnostic for OCD
- Labs are primarily used to rule out other conditions:
- CBC, ESR, CRP — if infection or inflammatory arthropathy is suspected
- Uric acid — if crystalline arthropathy is in the differential (rare in this age group)
- Vitamin D level — consider in patients with risk factors for deficiency
- Rheumatologic workup (ANA, RF) — only if clinical suspicion for inflammatory disease
12. Imaging
First-line: Plain radiographs [1-2][4]
- Four-view series: weight-bearing AP, tunnel/notch view, lateral, and axial patellar view (Merchant/sunrise at 30°–45° flexion)
- The tunnel (notch) view is critical — best visualizes the classic lesion on the lateral aspect of the medial femoral condyle [2]
- Assess for: focal subchondral lucency, sclerosis, fragment separation, loose bodies, physeal status
- Bilateral radiographs are recommended given high bilateral incidence [1]
Advanced imaging: MRI [1-3]
- Gold standard for assessing lesion size, location, depth, stability, and articular cartilage integrity
- MRI signs of instability: loss of cartilage cap, cystic changes, fluid tracking deep to the OCD lesion (high T2 signal rim), subchondral bone disruption, osteochondral defect [2][16]
- Overlying cartilage alteration has the highest discriminative performance for instability (AUC 0.92) [17]
- MRI criteria for instability are more specific in skeletally mature patients than in juvenile OCD [18-19]
- Pooled MRI sensitivity for instability: 92%; specificity: 85% (lower specificity in juvenile OCD at ~68%) [19]
CT: Not indicated initially; useful for postoperative healing assessment [2]
When imaging is unnecessary: Incidental, asymptomatic radiographic findings in very young children may represent normal ossification variants and do not always require MRI
13. Special Tests
- Hefti classification (MRI-based, 5 grades) and Nelson classification (4 groups) — most widely used staging systems; moderate inter-rater reliability [20]
- Novel 3-group MRI classification — simpler, near-perfect intrarater agreement [20]
- De Smet MRI criteria for instability — high signal rim, cysts, cartilage fracture line, fluid-filled defect [18]
- Arthroscopy — remains the definitive assessment of lesion stability and is both diagnostic and therapeutic [3-4]
- Ultrasound — emerging role for elbow OCD screening (not standard for knee) [3][21]
14. ECG
15. Assessment
OCD is classified by two key determinants that drive all management decisions:
Skeletal maturity [1-2][9]
- Juvenile OCD (open physes): better healing potential, higher nonoperative success (~50–65%) [2]
- Adult OCD (closed physes): poorer prognosis, greater propensity to instability [7-8]
Lesion stability [1][9-10]
- Stable: intact articular surface, no mechanical symptoms → amenable to conservative management
- Unstable: articular breach, fragment displacement, loose body → typically requires surgery
Favorable prognostic factors for nonoperative healing: age <12 years, open physes, smaller lesions, non-weight-bearing location, no mechanical symptoms. [1] Complications of untreated or poorly managed OCD include premature osteoarthritis, chronic pain, and functional disability. [3][22]
16. Treatment Plan
Conservative management (stable lesions, open physes) [1-2][9]
- Activity restriction: cessation of impact/pivoting sports for 3–6 months
- Protected weight-bearing with or without bracing (unloader brace may be considered)
- NSAIDs for pain control
- Physical therapy: maintain ROM and strength while avoiding aggravating activities
- Serial clinical and radiographic monitoring (repeat imaging at 3–6 months)
- Success rate: approximately 50–65% in juvenile OCD [2]
Surgical management [1][9-10][23]
Indications:
- Failed conservative treatment (persistent symptoms after 3–6 months)
- Unstable lesion on imaging or arthroscopy
- Closing physes with persistent symptoms
- Large lesions, atypical locations, mechanical symptoms
Procedures:
- Stable lesions (failed conservative): retroarticular or transarticular drilling to promote vascular channels and healing [1][23]
- Unstable but repairable lesions: drilling + fixation (bioabsorbable or metal screws) ± bone grafting — success in 67–100% of cases [10]
- Non-repairable/chronic lesions: autologous chondrocyte implantation (ACI), osteochondral autograft transfer (OATS), or osteochondral allograft [1][9]
- Non-viable fragments: excision with marrow stimulation (microfracture) — results are poor for large weight-bearing lesions [7]
Return-to-sport rates are >85% in skeletally immature patients regardless of treatment type. [1]
17. Disposition
- Outpatient management is appropriate for the vast majority of OCD cases
- Orthopedic referral (sports medicine or pediatric orthopedics): all confirmed OCD cases should be referred for definitive management planning [2][8]
- Urgent orthopedic consultation: mechanical symptoms (locking, catching), acute fragment displacement, or large effusion suggesting unstable lesion
- Admission: rarely required; only in the perioperative setting for complex surgical cases
- Observation: stable lesions undergoing conservative management require serial follow-up with repeat imaging
18. Follow Up / Return Precautions
- Follow-up timing: clinical reassessment every 4–6 weeks during conservative management; repeat imaging (radiographs ± MRI) at 3–6 months to assess healing [2]
- Return precautions — advise immediate reassessment for:
- New or worsening mechanical symptoms (locking, catching, giving way)
- Acute increase in pain or swelling
- Inability to bear weight
- Loss of range of motion
- Patient/family counseling:
- Compliance with activity restriction is critical for healing
- Symptoms do not always correlate with disease severity — radiographic healing must be confirmed [2]
- Risk of premature osteoarthritis if lesion progresses or is inadequately treated [3]
- Expected recovery: nonoperative healing typically takes 3–6 months; postoperative recovery varies by procedure (drilling: ~4–6 months; fixation/grafting: 6–12+ months) [2][9][23]
- Return to sport is guided by resolution of symptoms AND evidence of radiographic healing [2]
References
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2. The Adolescent Athlete and the Team Physician: A Consensus Statement. 2025 Update. — Putukian M, Leclere LE, Herring SA, et al. Medicine and Science in Sports and Exercise. 2026.
3. Osteochondritis Dissecans: Current Understanding of Epidemiology, Etiology, Management, and Outcomes. — Chau MM, Klimstra MA, Wise KL, et al. The Journal of Bone and Joint Surgery. American Volume. 2021.
4. The Diagnosis and Treatment of Osteochondritis Dissecans: Evidence-Based Clinical Practice Guideline. — American Academy of Orthopaedic Surgeons (2023). 2023.
5. The Demographics and Epidemiology of Osteochondritis Dissecans of the Knee in Children and Adolescents. — Kessler JI, Nikizad H, Shea KG, et al. The American Journal of Sports Medicine. 2014.
6. Incidence of Symptomatic Osteochondritis Dissecans Lesions of the Knee: A Population-Based Study in Olmsted County. — Pareek A, Sanders TL, Wu IT, et al. Osteoarthritis and Cartilage. 2017.
7. Management of Osteochondritis Dissecans of the Knee: Current Concepts Review. — Kocher MS, Tucker R, Ganley TJ, Flynn JM. The American Journal of Sports Medicine. 2006.
8. Selected Issues for the Adolescent Athlete and the Team Physician: A Consensus Statement. — Medicine and Science in Sports and Exercise. 2008.
9. Osteochondritis Dissecans Lesions of the Knee: Evidence-Based Treatment. — Nammour MA, Mauro CS, Bradley JP, Arner JW. The Journal of the American Academy of Orthopaedic Surgeons. 2024.
10. Management of Symptomatic Osteochondritis Dissecans of the Knee. — Waters T, Gowd AK, Waterman BR. Arthroscopy : The Journal of Arthroscopic & Related Surgery : Official Publication of the Arthroscopy Association of North America and the International Arthroscopy Association. 2020.
11. Overuse Injuries and Burnout in Youth Sports: A Position Statement From the American Medical Society for Sports Medicine. — DiFiori JP, Benjamin HJ, Brenner J, et al. Clinical Journal of Sport Medicine : Official Journal of the Canadian Academy of Sport Medicine. 2014.
12. Descriptive Epidemiology From the Research in Osteochondritis Dissecans of the Knee (ROCK) Prospective Cohort. — Nissen CW, Albright JC, Anderson CN, et al. The American Journal of Sports Medicine. 2022.
13. Osteochondritis Dissecans of the Knee Associated With Mechanical Overload. — van der Weiden GS, van Cruchten S, van Egmond N, et al. The American Journal of Sports Medicine. 2024.
14. A Comparative Analysis of Osteochondritis Dissecans and Avascular Necrosis: A Comprehensive Review. — Konarski W, Poboży T, Konarska K, et al. Journal of Clinical Medicine. 2024.
15. Osteochondritis Dissecans: Wilson's Sign Revisited. — Conrad JM, Stanitski CL. The American Journal of Sports Medicine. 2003.
16. Osteochondritis Dissecans of the Elbow in Children: MRI Findings of Instability. — Nguyen JC, Degnan AJ, Barrera CA, et al. AJR. American Journal of Roentgenology. 2019.
17. Lateral Femoral Condyle OCD Lesions in Children on Knee MRI. — Nguyen JC, Gendler L, Yaya-Quezada C, et al. Skeletal Radiology. 2026.
18. Juvenile Versus Adult Osteochondritis Dissecans of the Knee: Appropriate MR Imaging Criteria for Instability. — Kijowski R, Blankenbaker DG, Shinki K, et al. Radiology. 2008.
19. Clinical Value of MRI in Assessing the Stability of Osteochondritis Dissecans Lesions: A Systematic Review and Meta-Analysis. — Hu H, Zhang C, Chen J, et al. AJR. American Journal of Roentgenology. 2019.
20. Novel Magnetic Resonance Imaging Classification of Osteochondritis Dissecans of the Knee: A Reliability Study. — Hussain ZB, Mathew ST, Feroe AG, et al. Journal of Pediatric Orthopedics. 2021.
21. Osteochondritis Dissecans of the Elbow: Current Diagnosis and Management. — Haislup BD, Huff SD, Johnston PS, Ho JC, Murthi AM. The Journal of the American Academy of Orthopaedic Surgeons. 2026.
22. Osteochondritis Dissecans of the Knee in Young Athletes. — Chau MM, Tompkins MA. Clinics in Sports Medicine. 2022.
23. Editorial Commentary: Early Operative Management of "Stable" Osteochondritis Dissecans Lesions Confers Greater Value in Skeletally Immature Patients. — Waterman BR. Arthroscopy : The Journal of Arthroscopic & Related Surgery : Official Publication of the Arthroscopy Association of North America and the International Arthroscopy Association. 2021.