Jack Hanna, Trent Taros, Timothy R. Smith MD PhD, Carmen Vleggeert-Lankamp MD PhD
Timothy R. Smith, MD, PhD
Research Category: Musculoskeletal/Orthopedics/Sports Medicine
Background: Achondroplasia is the most common human skeletal dysplasia, causing disproportionate short stature with increased likelihood of spinal stenosis. Stenosis is also common in the general population, with lumbar-cervical tandem stenosis occurring at rates as high as 23.7%. We sought to quantify the rate of TSS in achondroplastic dwarfism.
Methods: We identified 26 adult patients with achondroplasia in a large academic medical center, a documented history of moderate to severe lumbar stenosis, and records of cervical spine imaging. We compared the number of patients with lumbar-cervical TSS to the overall number of patients with lumbar stenosis, and compared this proportion TSS incidence in patients without achondroplasia (23.7%) using a Fisher Exact Test.
Results: Of the 26 cases that met inclusion criteria, 16 cases showed a documented history of moderate or severe cervical cord compression (61.5%). A significant difference exists between this proportion and the incidence of TSS in patients without achondroplasia (p = .0201, α = .05).
Conclusion: There is a significantly higher likelihood of TSS in patients with achondroplasia in the examined cohort compared to patients without achondroplasia. Our results suggest that cervical spinal imaging should be considered in the management of lumbar stenosis in achondroplastic patients.
Achondroplasia is the most common cause of dwarfism, occurring in approximately 1 in 20,000 live births. A common condition in adult patients with achondroplasia is spinal stenosis (narrowing of the spinal canal). Stenosis occurs in approximately one third of achondroplastic patients, mostly in the lower-mid back. In the general population, spinal stenosis of the neck and back (aka Tandem Spinal Stenosis or TSS) accompany each other 23.7% of the time. The incidence of TSS in patients with achondroplasia is unknown.
The Research Patient Data Registry (RPDR) at Brigham and Women’s Hospital and Massachusetts General Hospital was queried, identifying 26 adult patients with achondroplasia, a history of moderate to severe lower spinal stenosis, and records of neck spinal imaging. Statistical analysis was conducted with Fischer’s Exact Test.
Of the 26 patients analyzed, 16 showed a documented history of moderate or severe cervical cord compression (61.5%). A significant difference exists between this percentage and the percentage of TSS in patients without achondroplasia (p = .0201, α = .05).
There is a significantly higher likelihood of TSS in patients with achondroplasia compared to patients without achondroplasia. Given these results, neck imaging should be considered when managing lumbar stenosis in patients with achondroplasia.