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PubMed This is a summary of 18 peer-reviewed journal articles Updated
Orthopedics

Symptoms, Causes, and Diagnosis of OCD

At a Glance

Osteochondritis Dissecans (OCD) is a joint condition caused by repetitive stress, alignment issues, or poor blood flow that leads to bone and cartilage breakdown. Diagnosis relies on X-rays and MRIs to check for joint damage, with key symptoms including aching, swelling, and the joint catching or locking.

Understanding why and how Osteochondritis Dissecans (OCD) develops is key to navigating the diagnostic process. OCD is a “multifactorial” condition, meaning it rarely has a single cause. Instead, it is typically the result of several biological and mechanical factors coming together to stress the joint [1][2].

Why OCD Happens: The Perfect Storm

The breakdown of the subchondral bone (the bone foundation) and the overlying articular cartilage is usually driven by three main factors:

  • Repetitive Microtrauma: This is the most common trigger. In active children and athletes, repetitive “micro-stresses” from sports like soccer, gymnastics, or baseball can overwhelm the bone’s ability to repair itself [2][3].
  • Mechanical Alignment: If limbs are not perfectly aligned—such as being bow-legged (varus) or knock-kneed (valgus)—it can shift the body’s weight onto one specific spot in the joint, causing that area to wear down faster [4][5].
  • Vascular Failure: Some areas of our joints have a naturally limited blood supply. If this “vulnerable” blood flow is interrupted, the bone can become ischemic (lacking oxygen), leading to localized bone death [6][7].

The Role of Genetics (The ACAN Gene)

While most cases of OCD are sporadic (happening by chance), an exceptionally rare group of patients may have multicentric OCD, where the condition appears in several different joints. In these extremely rare cases, a variant in the ACAN gene (which provides instructions for making a protein called aggrecan) may be responsible [8]. Aggrecan is vital for the strength of cartilage; if it is defective, the cartilage and bone are much more likely to fail [9]. Note that for the vast majority of patients, genetics do not play a primary role.

Recognizing the Symptoms

The symptoms of OCD often progress in a predictable pattern. Early recognition can prevent a stable lesion from becoming unstable.

Symptom Type Description
Early (Common) A vague, dull ache during or after sports; occasional swelling (effusion) [10][11].
Mid-Stage Pain that becomes more localized; a feeling that the joint is “unreliable” or may give way [11][12].
Red Flags Catching (a momentary hitch in motion) or Locking (the joint physically gets stuck and cannot move). These indicate a fragment may be loose [13][11].

The Diagnostic Path

When you visit the doctor, they will use a combination of tools to confirm the diagnosis and “stage” the lesion.

  • X-ray: This is the first step. It is used for screening and to determine if the physis (growth plate) is open or closed, which tells the doctor how much “natural healing power” is left.
  • MRI (The Gold Standard): While X-rays show the bone, the MRI is preferred for staging because it can see the cartilage and the fluid around the lesion [14][15]. Doctors look for a rim sign—a line of fluid behind the bone fragment that suggests it might be unstable [16]. Important Note: In young, growing children, a high T2 signal line (rim sign) behind the lesion can sometimes just be a normal part of the growing epiphysis or the early healing process. Therefore, pediatric MRIs are complex, and doctors must look for multiple signs (like cysts or surface breaks) before declaring a juvenile lesion unstable [17].
  • Differentials: OCD is sometimes confused with other conditions. In younger children, it can look like normal irregular ossification (a normal way bones grow) [1]. It may also be mistaken for acute fractures or overuse conditions like Osgood-Schlatter [1][18]. Determining the difference is essential for avoiding unnecessary treatment.

Common questions in this guide

What causes Osteochondritis Dissecans (OCD) in joints?
OCD is usually caused by a combination of factors, primarily repetitive stress or microtrauma from sports. Other contributing factors include mechanical alignment issues, like being bow-legged, or a localized lack of blood flow to the bone.
What are the signs that an OCD lesion is getting worse?
Early symptoms include a dull ache and occasional swelling. Red flags that the condition is progressing include the joint catching, locking, or feeling unstable, which may indicate a bone fragment has become loose.
How is Osteochondritis Dissecans diagnosed?
Doctors typically start with an X-ray to look at the bone and growth plates. An MRI is the gold standard for diagnosis, as it allows doctors to examine the cartilage and fluid to determine if the bone fragment is stable or unstable.
What does a 'rim sign' mean on my MRI report?
A rim sign is a line of fluid visible behind the bone fragment on an MRI. While it often suggests the bone fragment is unstable, in growing children it can sometimes be a normal part of the bone healing or growing process.
Are genetics responsible for my child's OCD?
For the vast majority of patients, genetics do not play a primary role. In extremely rare cases where OCD appears in multiple joints, a variant in the ACAN gene may be involved, which affects the cartilage's strength.

Questions to Ask Your Doctor

Curated prompts to bring to your next appointment.

  1. 1.Based on the MRI, is the cartilage cap still intact, or is there a 'rim sign' indicating it might be loose?
  2. 2.Are the symptoms typical for a 'stable' or 'unstable' lesion?
  3. 3.Could these imaging findings be a 'normal variant of ossification' rather than OCD in my growing child?
  4. 4.Do you notice any limb alignment issues, like 'knock-knees' or 'bow-legs,' that are contributing to this?
  5. 5.How do you differentiate this from an acute fracture or other conditions like Osgood-Schlatter?

Questions For You

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References

References (18)
  1. 1

    Understanding Osteochondritis Dissecans: A Narrative Review of the Disease Commonly Affecting Children and Adolescents.

    Konarski W, Poboży T, Konarska K, et al.

    Children (Basel, Switzerland) 2024; (11(4)) doi:10.3390/children11040498.

    PMID: 38671714
  2. 2

    Osteochondral Lesions of the Talus: A Review on Talus Osteochondral Injuries, Including Osteochondritis Dissecans.

    Bruns J, Habermann C, Werner M

    Cartilage 2021; (13(1_suppl)):1380S-1401S doi:10.1177/1947603520985182.

    PMID: 33423507
  3. 3

    Overuse injuries in sport: a comprehensive overview.

    Aicale R, Tarantino D, Maffulli N

    Journal of orthopaedic surgery and research 2018; (13(1)):309 doi:10.1186/s13018-018-1017-5.

    PMID: 30518382
  4. 4

    Lower limb malalignment on whole-leg radiography predicts medial or lateral talar osteochondral lesion location: Implications for osteoarthritis assessment.

    Henkelmann R, Greifeldt R, Hepp P, et al.

    Osteoarthritis and cartilage open 2026; (8(1)):100707 doi:10.1016/j.ocarto.2025.100707.

    PMID: 41438162
  5. 5

    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; (52(1)):155-163 doi:10.1177/03635465231211497.

    PMID: 38164681
  6. 6

    Three-Dimensional Quantitative Magnetic Resonance Imaging of Epiphyseal Cartilage Vascularity Using Vessel Image Features: New Insights into Juvenile Osteochondritis Dissecans.

    Ellermann JM, Ludwig KD, Nissi MJ, et al.

    JB & JS open access 2019; (4(4)) doi:10.2106/JBJS.OA.19.00031.

    PMID: 32043049
  7. 7

    Novel Application of Magnetic Resonance Imaging Demonstrates Characteristic Differences in Vasculature at Predilection Sites of Osteochondritis Dissecans.

    Tóth F, Nissi MJ, Ellermann JM, et al.

    The American journal of sports medicine 2015; (43(10)):2522-7 doi:10.1177/0363546515596410.

    PMID: 26286878
  8. 8

    Novel missense ACAN gene variants linked to familial osteochondritis dissecans cluster in the C-terminal globular domain of aggrecan.

    Stattin EL, Lindblom K, Struglics A, et al.

    Scientific reports 2022; (12(1)):5215 doi:10.1038/s41598-022-09211-y.

    PMID: 35338222
  9. 9

    Variable expressivity in a family with an aggrecanopathy.

    Denis A, Chergui S, Basalom S, et al.

    Molecular genetics & genomic medicine 2022; (10(1)):e1773 doi:10.1002/mgg3.1773.

    PMID: 34894100
  10. 10

    A Simple Clinical Predictive Model for Arthroscopic Mobility of Osteochondritis Dissecans Lesions of the Knee.

    Milewski MD, Miller PE, Gossman EC, et al.

    The American journal of sports medicine 2024; (52(14)):3543-3550 doi:10.1177/03635465241296133.

    PMID: 39584729
  11. 11

    Surgical treatment for osteochondritis dessicans of the knee.

    Winthrop Z, Pinkowsky G, Hennrikus W

    Current reviews in musculoskeletal medicine 2015; (8(4)):467-75 doi:10.1007/s12178-015-9304-9.

    PMID: 26409885
  12. 12

    Osteochondritis dissecans of the knee.

    Accadbled F, Vial J, Sales de Gauzy J

    Orthopaedics & traumatology, surgery & research : OTSR 2018; (104(1S)):S97-S105 doi:10.1016/j.otsr.2017.02.016.

    PMID: 29197636
  13. 13

    Concomitant Osteochondral Autograft Transplantation and Fixation of Osteochondral Fragment for Treatment of a Massive Osteochondritis Dissecans: A Report of 8-Year Follow-up Results.

    Lee BI, Kim BM

    Knee surgery & related research 2015; (27(4)):263-8 doi:10.5792/ksrr.2015.27.4.263.

    PMID: 26672950
  14. 14

    Treatment of Knee Chondral Defects in Athletes.

    Thacher RR, Pascual-Leone N, Rodeo SA

    Sports medicine and arthroscopy review 2024; (32(2)):75-86 doi:10.1097/JSA.0000000000000405.

    PMID: 38978201
  15. 15

    Juvenile Osteochondritis Dissecans: A Case Report.

    Nudelman H, Lőrincz A, Kassai T, Józsa G

    Diagnostics (Basel, Switzerland) 2024; (14(17)) doi:10.3390/diagnostics14171931.

    PMID: 39272716
  16. 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; (213(5)):1145-1151 doi:10.2214/AJR.19.21855.

    PMID: 31461319
  17. 17

    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; (213(1)):147-154 doi:10.2214/AJR.18.20710.

    PMID: 30995094
  18. 18

    Evaluation and management of knee pain in young athletes: overuse injuries of the knee.

    Patel DR, Villalobos A

    Translational pediatrics 2017; (6(3)):190-198 doi:10.21037/tp.2017.04.05.

    PMID: 28795010

This page explains the symptoms and diagnosis of Osteochondritis Dissecans for educational purposes. Always consult a pediatric orthopedist or sports medicine specialist to evaluate joint pain or interpret MRI results.

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