Modified closing-opening wedge osteotomy for the treatment of sagittal malalignment in thoracolumbar fractures malunion

Background context: Many techniques have been described for the surgical treatment of rigid posttraumatic thoracolumbar kyphosis, but none is well adapted to the modified shape of the wedged vertebra.

Purpose: The study aimed to describe the modified closing-opening wedge osteotomy (MCOWO), a new osteotomy technique that adapts to the triangular shape of the wedged apical vertebra of the deformity.

Study design: A retrospective assessment of the degree of correction before and after the MCOWO was carried out.

Patient sample: Ten patients presenting rigid posttraumatic thoracolumbar kyphosis were enrolled in this study.

Outcome measures: We used preoperative and postoperative whole spine radiographs to assess the sagittal plane parameters, and computed tomography scan for measurement of the vertebral segment height at the osteotomy level, spinal cord length, aorta length, and fusion rate.

Methods: Ten patients underwent the MCOWO at T12 or L1. The procedure involves removing the postero-superior triangular corner of the wedged vertebra and transforming it to a shape similar to a trapezoid.

Results: The patients' mean age was 36.6±7.5 years, the mean time between the fracture and the surgery was 12.2±5.6 months, and the mean follow-up was 30.6±5 months. In all patients, statistically significant improvement was observed in the sagittal plane after surgery. The thoracolumbar angle improved from 52±6° preoperatively to 7.1±5.7° at the last follow-up. Mean osteotomy angle was 38.1±2.6°, mean spinal cord shortening was 1.2±0.2 cm, and mean aorta lengthening was 2.3±0.4 cm. All the patients showed complete fusion at 2 years, and none required revision surgery. Two patients presented a temporary unilateral weakness that recovered completely within 3 months after the surgery.

Conclusions: The MCOWO is an interesting procedure for patients with posttraumatic thoracolumbar kyphosis. The modified osteotomy is adapted to the modified shape of the compressed vertebra. Spinal cord shortening and aorta lengthening were well tolerated in all patients.