Laminectomy in patients with achondroplasia: the impact of time to surgery on long-term function

Abstract

Study design: Retrospective analysis, survey.

Objective: To describe a cohort of individuals with achondroplasia undergoing thoracolumbar laminectomy and to examine if shorter time to surgery was related to improvement in long-term functional outcome.

Summary of background data: Data on the long-term benefits of laminectomy are mixed for such patients. Earlier intervention may be associated with greater likelihood of long-term benefit, but quantified data are lacking.

Methods: We retrospectively studied 49 patients with achondroplasia who underwent primary laminectomy for spinal stenosis. Patients completed a questionnaire to assess symptoms, walking distance, and independence (per Modified Rankin Scale), before surgery and currently. Responses were analyzed for the likelihood of improved walking distance or Rankin level.

Results: Our patients had the following mean values: age, 37.7 ± 10.6 years; body mass index, 31.8 ± 5.5; symptom duration, 74.0 ± 100.1 months; preoperative symptom severity score, 2.7 ± 1.0 points; mean changes in blocks walked, +0.39 ± 2.0; and Rankin level, +0.08 ± 1.47. Patients with a time-to-surgery interval of <6 months were 7.13 times (95% confidence interval [CI], 1.39-36.66) more likely to experience improvement in walking distance and 4.00 times (95% CI, 1.05-15.21) more likely to experience Rankin level improvement than patients whose interval was >6 months. Intervals of up to 12 and 24 months were associated with increased likelihoods of 4.95 (95% CI, 1.41-17.41) and 3.43 (95% CI, 1.05-11.22), respectively, of improved walking distance compared with those with longer time-to surgery intervals, but those Rankin level improvements were not statistically significant.

Conclusion: Time from symptom onset to surgery in patients with achondroplasia is an important predictor of long-term functional outcome. For sustained long-term postsurgical improvement, the window of opportunity might be relatively narrow. Patients with achondroplasia should seek medical advice for spinal stenotic symptoms as soon as possible.