Background: Spinal stenosis is a common complication of achondroplasia. To our knowledge, no study has evaluated a greater than 2-year outcome after surgical intervention for spinal stenosis in such children or compared decompression with and without instrumentation in relation to revision surgery. Our purpose was to assess the efficacy of lumbar decompression and instrumentation for symptomatic stenosis in children with achondroplasia.
Methods: We retrospectively reviewed our institution's database to identify children (≤18 y old) with achondroplasia undergoing initial spinal decompression for lumbar stenosis from 1995 through 2003. We identified 18 such patients and reviewed their medical records for demographic data, presenting signs and symptoms, and treatment and outcome data. Mean follow-up was 72.0±27.6 months. We determined each patient's symptom score (SS) based on presence of leg weakness, numbness, or pain; abnormal reflexes; incontinence; and walking intolerance (unable to walk ≥5 blocks). Each finding was scored 1 point (6 points maximum). Nine patients requiring revision surgery were assigned a revision postoperative SS. All patients were contacted at the end of data collection and assigned a final follow-up SS. Baseline SS values were compared with postoperative, revision postoperative, and final follow-up scores using a paired t test (α=0.05).
Results: The mean preoperative and final SS values were significantly different: 4.0±0.9 (most common symptoms, leg weakness and incontinence) and 1.6±1.7 (most common symptom, leg weakness), respectively. Nine patients underwent decompression with instrumentation initially; 9 did not; 7 of the latter required instrumentation during revision; and 2 of the former also required revision. Those without initial instrumentation were 3.5 times more likely (odds ratio=12.3) to require revision.
Conclusions: Surgical decompression with instrumentation significantly reduced the symptoms of lumbar stenosis and the likelihood of revision surgery in children with achondroplasia.
Level of Evidence: Level III therapeutic study.