Chondral fractures
Chondral fractures are fractures that involve the cartilage only unlike osteochondral fractures where the articular cartilage, as well as the subchondral bone plate, are involved .
Epidemiology
Chondral fractures typically occur in combination with ligamentous injuries in young adults but can be seen in isolation in adolescents.
Clinical presentation
Clinical symptoms are variable and depend on the extent and the associated injuries Usual complaints are pain, limited motion, locking, clicking and a swollen joint. Since they are often associated with ligamentous injuries or occur in the context of dislocations they might stay undetected, if not meticulously searched for.
Pathology
Chondral fractures are a form of cartilage injury with disruption of the articular cartilage usually as a result of rotational injuries or direct blows leading to a focal chondral defect with the fragment remaining in situ or displaced and loose .
Etiology
Articular injuries are a result of shear forces or shear stress such as in:
- distortions
- dislocations
Radiographic features
Pure chondral fragments are not easily detectable neither on a plain radiograph nor on conventional computed tomography.
MRI
A focal chondral defect within the articular cartilage, with chondral fragments. They are of intermediate signal intensity in T1 and PD and are hypointense in T2 and fat-saturated T2 and intermediate-density weighted Images and are best detected on normal, not fat-saturated proton- or intermediate-density images or T2-weighted images due to the improved contrast versus synovial fluid .
CT / MR arthrography
Focal chondral defect with a chondral fragment in place with undermining contrast alongside the bone-cartilage interface similar to chondral delamination. Loose chondral fragments can be detected.
Treatment and prognosis
Chondral fractures are usually treated arthroscopically or operatively. If they are suitable for rescue and technical fixation, they can be repaired with a variety of implants including bioabsorbable pins, darts screws and sutures . If refixation is not possible any loose and/or unstable chondral fragments have to be removed with debridement of the focal chondral defect , with potentially further following restorative therapy such as microfracture, autologous chondrocyte implantation (ACI), osteochondral autograft transfer (OAT) .
Conservative management can be done for pain relief but not to restore articular cartilage .
See also
