---

Osteochondritis Dessicans

Osteochondritis dessicans is a condition of uncertain, multifactorial etiology which is often found unexpectedly on x-rays of the knee joints when investigation is being completed for other reasons. Therefore, this condition can be erroneously blamed for knee symptomatology caused by trauma.

Osteochondritis dessicans occurs in juvenile and adult populations, often in the absence of any history of trauma.  It is four times more common in males than females.  The right leg is predominately affected.

There are many theories regarding etiology, ranging from traumatic ischemia to accessory centers of ossification.

The theory of ischemia (insufficient blood flow resulting in decreased tissue oxygenation) proposes that obstruction of end arterioles in the femoral condyles precipitates structural change in cartilage and bone causing these tissues to separate from one another.  The resultant lesions are classical for the diagnosis of osteochondritis dessicans.

There is also a genetic theory suggesting an increased incidence of osteochondritis dessicans in some families.

Accessory centers of ossification (extra centers from which bones grow) can be seen in skeletally immature individuals and mistaken for osteochondritis dessicans.

Despite initial theories suggesting traumatic origin, recent medical review indicates that only 40% of patients with a history of osteochondritis dessicans also have a history of trauma; this is usually minimal to moderate in severity and insufficient to have caused a fracture.

In fact, ostochondritis dessicans is different than an osteochondral fracture, which is a traumatic joint injury consisting of the shearing off of bone (osteo), accompanied by its articular cartilage (chondral).

If there has been a history of trauma sufficient to cause an osteochondral fracture, the patient would most commonly present with acute swelling, crepitus (grinding sound) and locking of the knee joint.  There would be associated joint line tenderness, limitation of range of motion and pain/restricted range with the bounce, squat and McMurray tests. 

Hughston's study on osteochondritis dessicans of the femoral condyles shed little light on the etiology of this condition.  Although 60% of those studied had participated in athletics, only 21% could relate the onset of symptoms to a specific injury.  Importantly, in this latter group, the radiographic and gross appearance of the lesions indicated that the disease had been present long before the described injury.

In summary, it is reasonable to conclude that the exact cause of osteochondritis dessicans is uncertain.  Etiology is probably multifactorial and infrequently associated with trauma.

References

Hughston, J. C., Hergenroeder, P. T.:  Ostochondritis Dissecans of the Femoral Condyles.  Journal of Bone and Joint Surgery, Vol. 66-A, no. 9, December 1984: pp. 1340-1348.

Federico, D. J., Lynch, J.K., Jokl, P.:  Osteochondritis Dissecans of the Knee:  A Historical Review of Etiology and Treatment.  Vol. 6, No. 3, 1990:  pp 190-197.

[ back to top ]

---

Web site terms of use | Contact us