Achondroplasia Status and Adverse Short-term Postoperative Outcomes in Elective Spinal Decompression Surgery: A Propensity Score-matched Case-control Study

Introduction: Achondroplasia is the most common form of skeletal dysplasia, affecting approximately 1 in 25,000 individuals in the US. Previous research suggests that achondroplasia patients undergoing spine surgery have worse postoperative outcomes. Most of these findings are based on small, single-center retrospective studies and describe the impact of achondroplasia status on only one or two outcomes. We sought to assess the association between achondroplasia and a comprehensive battery of postoperative care outcomes in a national cohort.

Methods: The IBM Watson Health MarketScan claims database and associated Medicare Supplement were queried for adult patients diagnosed with achondroplasia who underwent elective thoracic or lumbar decompression +/- fusion surgery between 2006 and 2023. Propensity score matching was used to identify an equal number of age and sex-matched controls without achondroplasia. Outcomes of interest were length of hospital stay, non-home discharge disposition, 90-day readmission and postoperative medical or surgical complications. Bivariate analyses were conducted to examine the distribution of baseline characteristics based on achondroplasia status. Multivariate regression was employed to assess the association between achondroplasia status and short-term postoperative outcomes.

Results: Overall, 111 achondroplasia cases and an equal number of age- and sex-matched controls were included. Compared to controls, those with achondroplasia were more likely to have a longer length of hospital stay (B: 3.34, 95% CI: 1.00-4.70), non-home discharge (OR: 20.51, 95% CI: 5.78-72.73) and a higher complication rate (OR: 3.63, 95% CI: 1.49-8.87). The association between achondroplasia status and 90-day readmission did not reach statistical significance (p = 0.48).

Conclusion : Patients with achondroplasia undergoing spinal surgery experience worse overall short-term postoperative high-value care outcomes compared to their age- and sex-matched counterparts. Patient-specific factors may contribute to the higher complication rates observed. While the presence of achondroplasia is unchangeable, surgeons should be prepared for increased risks in their management plans. These findings highlight the need for tailored preoperative assessments and enhanced postoperative strategies to improve outcomes in this vulnerable population.