A 17 year old teenager presented as an emergency with right knee pain following a fall off his skateboard.The initial radiograph was unremarkable.An MRI scan revealed an osteochondral fracture of the lateral femoral condyle.We discuss the radiographic and MRI features of osteochondral fractures and the sensitivities of these modalities.
A 17 year old male presented with sudden onset right knee pain in A&E after jumping off a skateboard.Anteroposterior and lateral radiographs showed a large suprapatellar effusion but no evidence of a bony injury or partella dislocation. Due to the persistence of his symptoms and the presence of the effusion an MRI of the right Knee was carried out. This revealed the presence of an osteochondral fracture of the lateral femoral condyle. On reviewing the plain films in retrospect there was no visible fracture to be seen. However the MRI showed clearly a break in the cortex on the weight bearing surface of the lateral condyle and at least one small fragment of bone within a cystic area beneath the cortex .The overlying cartilage was disrupted and on the coronal images a fracture line was seen extending through the lateral corner of the femoral condyle and there was an associated area of bone marrow oedema in the distal femoral epiphysis.
Osteochondral fractures occur on the articular surfaces of the weightbearing joints.The fragment consists of a layer of articular cartilage and subchondral bone.They occur due to direct impact or twisting forces on the articular surfaces.Osteochondral fractures most often seen on the posterolateral aspect of the medial femoral condyle.They often occur in conjuction with patellar dislocation. After an osteochondral fracture the defect fills with fibrin clot and injury to bone releases multiple growth factors. Clinical manifestations include diffuse pain along the joint line locking of the knee due to loose body, crepitus during knee extension/flexion,a joint effusion,but the ligaments are usually stable. If not recognised early a full thickness defect can result in further damage to the joint. Loose fragments within the joint can lead to further damage to the articular surface.A tunnel view on the plain radiograph is often useful as the anteroposterior view may not always show the ostechondral defect or loose body.MRI findings usually correlate well with arthroscopic findings and may be used to determine whether the fragment is detached. The prognosis depends on the age of the patient; skeletally immature patients having a better prognosis. The prognosis is worse if the fragment detaches.Operative treatment aims at maintaing a congruous joint and removing the lose fragments. There have been attempts at autogenous grafting of osteochondral defects but in general this is an area still waiting for development. The differential diagnosis incudes Osteochondritis Dissecans the exact aetiology of which remains unknown although ,repetitive trauma,avascular necrosis,and genetic factors have been suggested. Another common site for osteochondral fractures is the dome of the talus in the ankle joint.
Osteochondral fracture of the right lateral femoral condyle .
According to the provided X-ray images, there are no obvious abnormalities in the continuity of the bone in the right knee joint. The joint space is normal, and no distinct fracture lines are visible. The overall alignment of the joint is good, but subtle lesions on the articular cartilage surface cannot be accurately evaluated.
MRI indicates an abnormal signal deep in the right lateral femoral condyle, suggesting edema or effusion in the subchondral bone. The integrity of the local cartilage surface appears to be compromised, and there is a significant bone marrow edema–like signal beneath the articular surface. This region is adjacent to the articular surface, suggesting a possible osteochondral injury. There is no clear evidence of a large meniscal tear, but further MRI sequences should be reviewed carefully.
In summary, the MRI confirms signs of osteochondral injury in the articular cartilage and subchondral bone layer, consistent with the imaging findings of a post-traumatic osteochondral fracture.
Based on the patient’s adolescent age, the acute injury (skateboarding fall), and MRI findings involving the cartilage and subchondral bone of the lateral femoral condyle of the right knee, the most likely diagnosis is osteochondral fracture of the lateral femoral condyle of the right knee.
1. Treatment Strategy:
2. Rehabilitation/Exercise Prescription Recommendations:
Throughout rehabilitation, closely monitor pain and joint swelling. If severe discomfort or swelling occurs, discontinue or reduce the activity immediately and consult a physician.
Disclaimer: The medical analysis report provided is for academic reference only and does not replace face-to-face clinical diagnosis or professional medical advice. If you have any questions or changes in your condition, please consult a relevant specialist promptly.
Osteochondral fracture of the right lateral femoral condyle .
