Free medial femoral condyle osteocutaneous flap for repairing stage IIIB osteonecrosis of the lunate: a case report

Abstract

Background There are several surgical options for osteonecrosis of the lunate, and confirming the effectiveness of various surgical methods remains challenging. Here, we present a case of stage IIIB osteonecrosis of the lunate repaired with a free medial femoral condyle osteocutaneous flap. Case presentation A 43-year-old male construction worker was admitted to our hospital due to right wrist pain, impaired mobility, and pain aggravated by activity for 10 months. The patient was diagnosed with stage IIIB osteonecrosis of the lunate based on the orthopantomogram and magnetic resonance imaging of the right wrist. Considering the patient’s medical history, physical examination, auxiliary examination, and wishes, reconstruction was performed using a free medial femoral condyle osteocutaneous flap. After the flap survived completely, the K-wires were removed one month after the operation, the external brace was removed two months after the operation, and functional wrist rehabilitation was initiated. After six months of follow-up, the wrist swelling and pain resolved, and the reconstructed lunate bone was viable. Additionally, the last follow-up was conducted in the sixth month after surgery; the affected hand grip strength improved from about 70% (28 kg) to 80% (32 kg) compared with the healthy side (40 kg); the visual analog scale score decreased from 6.5 points before the operation to 1 point; and the MAYO score increased from 60 points before the operation to 85 points. Conclusions The success of this case reinforces the potential of the free medial femoral condyle osteocutaneous flap as a new treatment option for stage IIIB osteonecrosis of the lunate and further expands the existing treatment options. Using a free medial femoral condyle osteocutaneous flap to reconstruct the lunate and restore the carpal anatomy may.