[Anterior open wedge osteotomy of the distal femur]

To treat instability caused by a genu recurvatum using ventral open wedge osteotomy of the distal femur.

Knee instability caused by Genu recurvatum with femoral extension deformity.

Inadequate blood flow to the lower extremity, soft tissue issues, obesity, osteoporosis.

Through a primary medial approach to the distal femur, a ventral open wedge osteotomy is performed using chisel bunch formation and arthrodesis spreader. For symmetrical expansion, another lateral approach at the distal femur and insertion of another arthrodesis spreader is performed. Osteosynthesis was performed with an angle stable plate from the medial side and with additional stabilization using a 4-hole angle stable plate from the lateral side. The osteotomy gap was filled with a bone graft wedge.

Partial weight-bearing of 20 kg was allowed for 6 weeks with passive exercise and lymphatic drainage. A hard frame orthosis for immobilization at 0-10-90° was fitted for 6 weeks. Radiographic controls were performed at 6 weeks, 3 months, and 1 year. After the last radiographic control, hardware was removed.

There are no reports in the current literature regarding the effect of a change in the sagittal plane at the distal femur on alignment, stability, and biomechanics of the knee. This case report shows that genu recurvatum with physiological posterior tibial slope can be successfully treated with anterior femoral flexion osteotomy. Hyperextension was completely eliminated at the follow-up examination after hardware removal after 12 months.