Misplacement of knee implants can be responsible for restricted ROM even in patients without arthrofibrosis so this is especially important in haemophilia patients. Patella baja or inferior position of the patella correlates closely with loss of ROM. Other considerations include a balanced flexion and extension gap so the implants have ligament stability without being too tight in flexion or extension. Increasing thickness of the patella by removing too little bone or inserting a patellar

CH5424802 button that is too thick may reduce flexion. This can also occur if the femoral component is placed too anterior. Reduced flexion can also occur if the femoral component is too posterior or too large. Templating the preoperative X-rays will help estimate the proper size of implants but the most critical part is accurate measurement and proper placement at surgery. If at trial reduction some flexion contracture remains, the posterior capsule is released from the distal femur under direct vision. As the capsule is released, the surgeon’s non-dominant hand pushes the posterior capsule away from the femur to protect the popliteal neurovascular structures. The suprapatellar fat covering the anterior distal femur should be

preserved, as it is a barrier to quadriceps adhesion. In patients where it has been selleck chemical replaced by fibrous tissue, restoration of motion is especially challenging. In patients with severe, long-standing flexion contractures serial casting and physical therapy preoperatively may help. Utilizing these methods, it is usually possible to get good, functional ROM at the time of surgery. The problem is keeping it. In patients with inadequate patellar 上海皓元医药股份有限公司 thickness for component fixation, patellectomy is the procedure of choice. This surgery

has been associated with improved ROM in the stiff knee. Most patellectomy patients have an extensor lag for several months that resolves to minimal or no lag. Patients going to surgery with very limited flexion may require quadricepsplasty, which is often associated with an extensor lag for six months or longer. It is important not to overlengthen the extensor mechanism to avoid a permanent extensor lag. The CPM may be useful for 4–6 h during the day, especially prior to physical therapy. It facilitates flexion but is not as helpful for gaining extension as a knee immobilizer, which is recommended at night for patients with a flexion contracture. Use of a towel roll under the ankle periodically during the day also helps gain extension. Residual haemarthrosis will stimulate arthrofibrosis. Postoperative drains are used in all of these patients and left in place until the output is <20cc per shift, usually 48 h.