Compressive Myelopathy in Congenital Kyphosis of the Upper Thoracic Spine: A Retrospective Study of 6 Cases.

STUDY DESIGN: A retrospective study.

OBJECTIVE: The goal of this retrospective study was to describe the uncommon presentation of neurological deficits in patients with congenital kyphosis of the upper thoracic spine (T1-T4).

SUMMARY OF BACKGROUND DATA: Congenital kyphosis is an uncommon deformity but can potentially lead to spinal cord compression and paraplegia, particularly in type I (failure of formation) deformities. Few reports have described compressive myelopathy associated with congenital kyphosis of the upper thoracic spine.

METHODS: Six patients with congenital kyphosis of the upper thoracic spine, including 2 adults and 4 pediatric patients, developed progressive or sudden onset of paraplegia. Angles of kyphosis ranged from 75 to 120 degrees. Magnetic resonance imaging demonstrated spinal cord thinning and compression at the kyphotic apex in all patients. All patients underwent decompressive and correctional surgery by single-stage posterior vertebral column resection or 2-stage anterior corpectomy fusion and posterior fixation. Neurological status was evaluated using the ASIA impairment classification and the motor score.

RESULTS: Postoperatively, all patients had 25%-80% correction of kyphosis. All patients improved neurologically between 0 and 2 ASIA scales after surgery. Among them, an adolescent patient presenting as acute ASIA A improved to ASIA E within 1 year after surgery. Another adolescent patient deteriorated from preoperative ASIA C to ASIA A in the immediate postoperative period but improved to ASIA D within 1 year after surgery.

CONCLUSIONS: Congenital kyphosis of the upper thoracic spine has a high incidence of compressive myelopathy. Duration from onset of paraplegia to surgical intervention and severity of preoperative paraplegia are 2 key factors in determining neurological prognosis after surgery.