Fracture Femur Hoffa Fracture

Hoffa fracture is a coronal split of the posterior condyle of the femur. Hoffa fracture is a rare intra-articular fracture of the posterior femoral condyle occurring from violent trauma, and generally occurs in young adults. Three types of Hoffa fractures are described. This classification is based on the location of the fracture within the condyle. Hoffa fracture can be an isolated fracture; however, it is often associated with other distal femur fractures. 38% of intra-articular distal femur fractures may have a Hoffa fracture (coronal plane fracture). The Hoffa fracture is a lot more common in open fractures than in closed fractures. Fracture may occur in either condyle, but the lateral condyle is the most common one to be affected by Hoffa fracture. It affects a single condyle in about 75% of the time, and the lateral condyle in about 85% of the time. Hoffa fracture occurs due to axial compression in a flexed knee. The mechanism of injury is controversial. The fracture is coronal, and it can be missed on routine lateral x-rays. The undisplaced fracture of the condyle may become displaced if the fracture is missed. The Hoffa fracture is almost like the capitellar fracture of the elbow. This fracture has the same story as the capitellar fracture, it is hidden, and you can miss it on the x-ray (you must look for it). CT scan is very helpful in the diagnosis of Hoffa fracture and will give you great details about the articular surface of the distal femur, especially if the fracture is comminuted. X-rays are not very good in diagnosing the Hoffa fracture. 20% of Hoffa fractures are diagnosed with x-rays only, so the CT scan is the best study for diagnosing the Hoffa fracture. Use a high degree of suspicion in the diagnosis of this fracture because the fracture may be subtle, and you may not be able to see it on routine x-rays. Treatment is reduction and stabilization of the fracture. stabilization of the fragment is usually done by headless compression screws and can be buried underneath the surface. Fixation can be done from either the anteroposterior (AP) direction or the posteroanterior (PA) direction. It can be temporarily fixed with k-wires. Permanent fixation is done with headless compression screws.

McMurray’s Test Meniscal Tear

McMurray’s test is a commonly used test in orthopaedic examination to test for tears of the meniscus. The McMurray’s test is a rotational maneuver of the knee that is frequently used in the examination of the patient to help in the diagnosis of meniscal tears. Meniscus injuries are very common. When the patient sustains an injury of the knee and has a meniscal tear, usually the patient complains of knee pain localized to the medial or lateral side of the knee. The patient may also have locking and clicking. Sometimes the patient will have an effusion and sometimes this effusion is small (swelling of the knee). Joint line tenderness is the most sensitive finding. Joint line tenderness can be on the medial side (medial meniscal tear) or on the lateral side (lateral meniscal tear). There will be minimal swelling of the knee and possible extension lag (locked knee) due to a displaced bucket handle tear of the meniscus. Pain at a higher level than the joint is usually associated with medial collateral ligament tear. If an MCL tear is present, it is usually avulsed from the medial femoral condyle. The MCL is rarely avulsed from the tibia. Pain at a lower level is usually associated with the pes anserine bursitis. McMurray’s test is a knee examination test that shows pain or a painful click as the knee is brought from flexion to extension with either internal or external rotation of the knee. The McMurray’s test uses the tibia to trap the meniscus between the femoral condyles of the femur and the tibia. When performing the McMurray’s test, the patient should be lying supine with the knee hyperflexed. The examiner then grasps the patient’s heel with one hand and places the other hand over the knee joint. To test the medial meniscus, the knee is fully flexed, and the examiner then passively externally rotates the tibia and places a valgus force. The knee is then extended in order to test the medial meniscus. To test the lateral meniscus, the examiner passively internally rotates the tibia and places a varus force. The knee is then extended in order to test the lateral meniscus. A positive test is indicated by pain, clicking or popping within the knee joint and may signal a tear of either the medial or lateral meniscus when the knee is brought from flexion to extension. There are mixed reviews for the validity of this test. There are other clinical tests that are as good as the McMurray’s test, however MRI is making the diagnosis of a meniscal tear easier. MRI is very sensitive, and it also excludes other associated injuries. I find that the McMurray’s test is valuable in getting insurance approval for performing an MRI. If you state that the McMurray’s test is positive, then the insurance will approve the MRI. Nowadays though, the McMurray’s test does not give us a lot of valuable clinical information, because we get the information from other tests.