Total hip replacements (THR) with modular femoral components (stem-neck interface) make it possible to adapt to extramedullary femoral parameters (anteversion, offset, and length) theoretically improving muscle function and stability. Nevertheless, adding a new interface has its disadvantages: reduced mechanical resistance, fretting corrosion and material fatigue fracture. We report the case of a femoral stem fracture of the female part of the component where the modular morse taper of the neck is inserted. An extended trochanteric osteotomy was necessary during revision surgery because the femoral stump could not be grasped for extraction, so that a long stem had to be used. In this case, the patient had the usual risk factors for modular neck failure: he was an active overweight male patient with a long varus neck. This report shows that the female part of the stem of a small femoral component may also be at increased failure risk and should be added to the list of risk factors. To our knowledge, this is the first reported case of this type of failure.

No abstract

No abstract

Case: We report the case of an 11-year-old child who presented with knee pain and moderate limp associated with knee flexum, without trauma history. Radiographic investigations including a magnetic resonance imaging showed a large cyst that seemed to have developed anteriorly from the anterior cruciate ligament, causing the loss of terminal extension, mimicking a cyclops syndrome-like of the knee. Knee arthroscopy with debridement of the cyst was performed, and the patient quickly recovered his range of motion. Histological analysis confirmed a synovial cyst in accordance with arthroscopic and radiological findings. Conclusion: This case is interesting because of the rare occurrence of ganglion cysts in children.

No abstract