Osteochonritis Dissecans
Pathophysiology and Etiology
Osteochondritis Dissicans is a described as lesions mainly affecting the subchondral bone of joints. Osseous resorption occurs making articular cartilage vulnerable to injury. This results in loose bodies from bone and cartilage within the joint space causing pain. The most common area affected is the medial femoral condyle. The lateral femoral condyle, the patella, and the femoral trochlea can also be affected. If a lesion is present it is staged for stability through an MRI according to Dipaola et al’s following classification:
I. Thickening of articular cartilage and low signal change (stable)
II. Articular cartilage breached; low signal rim behind fragment indication fibrous attachment (stable)
III. Articular cartilage breached; high signal changes behind fragment indicating synovial fluid between fragment and underlying subchondral bone (unstable)
IV. Loose body (unstable)
Its cause is unknown and not fully understood. However, repetitive trauma, ischemia, genetics, and endocrine disorders have been found to be possible causes.
I. Thickening of articular cartilage and low signal change (stable)
II. Articular cartilage breached; low signal rim behind fragment indication fibrous attachment (stable)
III. Articular cartilage breached; high signal changes behind fragment indicating synovial fluid between fragment and underlying subchondral bone (unstable)
IV. Loose body (unstable)
Its cause is unknown and not fully understood. However, repetitive trauma, ischemia, genetics, and endocrine disorders have been found to be possible causes.
Diagnostic Tools
- MRI
- Radiographs of the joint
- Bone scans
- Arthroscopic examinations
- Wilson Sign
Signs and Symptoms
The symptoms are intermittent and occur as a result of physical activity, especially walking up stairs or inclines.
- Swelling
- Stiffness
- Locking
- Catching
- Antalgic gait
- Tenderness at the anteromedial part of the knee
- Anterior knee pain
Prognosis
The patient’s age at which the symptoms began to occur seems to be an important factor in prognosis where younger patients have a better prognosis versus adults. There is poor prognosis in cases where the lesion has been unstable for an extended period of time and involves a weight-bearing region of the knee.
References
Dipaola JD, Nelson DW, Colville, MR: Characterizing osteochondral lesions by magnetic resonance imaging. Arthroscopy 7:101-104, 1991
Dutton, M. Orthopaedic examination, evaluation, and intervention. 2nd. New York,NY: McGraw-Hill, 2009. Print.
Crawford, D.C. & Safran, M.R. Osteochondritis Dissecans of the Knee. J Am Acad Ortho Surg. 2006;14:90-100.
Hixon, A.L. & Gibbs, L.M. Osteochondritis Dissecans: A Diagnosis Not to Miss. Am Fam Physician. 2000;61:151-6,158.
Johnson, M.P. Physical Therapist Management of an Adult with Osteochondritis Dissecans of the Knee. Physical Therapy. 2005;85:665-675.
Kocher, M.S., Tucker, R., Ganley, T.J. & Flynn, J.M. Management of Osteochdonritis Dissecans of the Knee. The American Journal of Sports Medicine. 2006;43:1181-1191.
Kon, E., Vannini, F., Buda, R., Filardo, G., Cavallo, M., Ruffilli, A., Nanni, M., Di Martino, A., Marcacci, M., & Giannini, S. How to Treat Osteochondritis Dissecans of the Knee: Surgical Techniques and New Trends. J Bone Joint Surg Am. 2012;94:e1(1-8).
Obedian, R.S. & Grelsamer, R.P. Osteochondritis Dissecans of the Distal Femur and Patella. Clinics in Sports Medicine. 1997;16:158-174.
Dutton, M. Orthopaedic examination, evaluation, and intervention. 2nd. New York,NY: McGraw-Hill, 2009. Print.
Crawford, D.C. & Safran, M.R. Osteochondritis Dissecans of the Knee. J Am Acad Ortho Surg. 2006;14:90-100.
Hixon, A.L. & Gibbs, L.M. Osteochondritis Dissecans: A Diagnosis Not to Miss. Am Fam Physician. 2000;61:151-6,158.
Johnson, M.P. Physical Therapist Management of an Adult with Osteochondritis Dissecans of the Knee. Physical Therapy. 2005;85:665-675.
Kocher, M.S., Tucker, R., Ganley, T.J. & Flynn, J.M. Management of Osteochdonritis Dissecans of the Knee. The American Journal of Sports Medicine. 2006;43:1181-1191.
Kon, E., Vannini, F., Buda, R., Filardo, G., Cavallo, M., Ruffilli, A., Nanni, M., Di Martino, A., Marcacci, M., & Giannini, S. How to Treat Osteochondritis Dissecans of the Knee: Surgical Techniques and New Trends. J Bone Joint Surg Am. 2012;94:e1(1-8).
Obedian, R.S. & Grelsamer, R.P. Osteochondritis Dissecans of the Distal Femur and Patella. Clinics in Sports Medicine. 1997;16:158-174.