Osteochondritis Dissecans

Modern Study Review (AI-Generated)

High-Yield Summary

Osteochondritis Dissecans (OCD) is a focal, idiopathic lesion of subchondral bone with potential secondary cartilage involvement, most commonly affecting the knee in adolescents and young adults. Early diagnosis and assessment of lesion stability are critical to guide treatment and optimize joint preservation. Age, lesion size, and stability on MRI are the primary factors influencing management decisions, with surgical intervention favored in older or unstable lesions to prevent progression to osteoarthritis.

Key Diagnostic Findings

Anatomy

OCD primarily affects the subchondral bone and overlying articular cartilage, most commonly at the medial femoral condyle of the knee.
Lesions can also occur in the capitellum, talus, and other joints.

Clinical Presentation

Patients typically present with activity-related joint pain, swelling, and sometimes mechanical symptoms such as catching or locking.
Adolescents around the age of 12 are a key demographic; skeletal maturity influences healing potential.

Imaging

MRI is the gold standard for assessing lesion stability, cartilage integrity, and presence of fluid behind the fragment.
Radiographs are useful for initial detection and monitoring but less sensitive for stability.
MRI signs of instability include:
High-signal rim behind the lesion on T2-weighted images
Disruption of articular cartilage
Cystic changes or fluid between fragment and bone

Classification Systems

Classification	Description	Clinical Relevance
Hefti Classification (MRI-based)	Grades lesion stability from I (stable) to V (displaced fragment)	Guides surgical decision-making
Dipaola Classification	Stages OCD based on MRI findings (early to late)	Assesses healing potential
Rockwood Classification (less commonly used)	Focuses on fragment displacement and stability	Historical reference

Current Gold Standard Treatment

Non-operative

Indicated primarily for stable lesions in skeletally immature patients (<12 years) with intact cartilage and no fragment displacement.
Includes activity modification, protected weight-bearing, and serial imaging to monitor healing.
Success rates are higher in younger patients due to better healing potential.

Operative

Indicated for:
Unstable or displaced lesions
Symptomatic lesions in patients >12 years or those failing conservative treatment
Surgical options include:
Arthroscopic drilling (to stimulate revascularization) for stable but symptomatic lesions
Fragment fixation with bioabsorbable screws or pins for unstable but salvageable fragments
Lesion removal, bone grafting, and fixation for displaced fragments or loose bodies
Advanced techniques: osteochondral autograft transplantation or autologous chondrocyte implantation in select cases

Modern Complications & Outcomes

Complications

Complication	Description
Nonunion or fragment non-healing	Persistent instability or fragment necrosis
Progression to osteoarthritis	Due to cartilage damage or untreated instability
Hardware irritation or failure	From fixation devices
Joint stiffness or arthrofibrosis	Postoperative complication

Outcomes

Prognosis depends on age, lesion stability, and timely intervention.
Younger patients with stable lesions have excellent outcomes with conservative management.
Surgical fixation restores joint congruity and function in unstable lesions, reducing long-term arthritis risk.
Residual symptoms or degenerative changes may occur in large or chronic lesions.

Classic Clinical Notes

OCD

Approach to Osteochondritis Dissecans

Principles of Treatment

Age is a huge factor – before or after 12 is a big deal. You look at these patient populations kinda differently.

Size of fragment is important.

Stability of fragment is important – can be assessed on MRI.

In the Patient 12 Years of Age

In this population, you are leaning to fix the lesion. They do not heal as well with the conservative approach. MRI on almost all of these.

MRI: Is the cartilage intact? Is there fluid behind? Is the piece unstable? Has the piece displaced completely already?

If symptomatic and stable – lean towards scoping and drilling.

If symptomatic and unstable – be prepared to scope then open the thing up, even take the lesion out, bone graft the base, and fix it.

Last Updated on January 25, 2026 by orthonet