Symptomatic spinal stenosis in adults with achondroplasia
Svein Fredwall, MD, Ph.D., a healthcare professional at Sunnaas Rehabilitation Hospital, TRS National Resource Centre for Rare Disorders, Nesodden, Norway, is working on the Norwegian Adult Achondroplasia Study, and this work on symptomatic spinal stenosis in adults with achondroplasia is the first of three articles.
This first article "High prevalence of symptomatic spinal stenosis in Norwegian adults with achondroplasia: a population-based study", was published in May 2020. And although it is a study conducted solely in Norway, the results are highly relevant to understand the natural history of achondroplasia and its effects in a longer time frame in life.
Study article Summary
Symptomatic spinal stenosis (SSS) is a well-known medical complication in achondroplasia. The reported prevalence of SSS is 10 to 30%, an estimate based on small studies or selected populations. No population-based studies exist currently. Furthermore, the relationship between SSS and physical functioning has not been investigated in detail. The aims of this study were to describe the prevalence of SSS in Norwegian adults with achondroplasia and to explore the impact of SSS on physical functioning.2
Stenosis, which means narrowing, can cause pressure on your spinal cord or the nerves that go from your spinal cord to your muscles. Lumbar spinal stenosis is a narrowing of the spinal canal in the lower part of your back.3
Results
In total, 50 participants were included (27 males, 23 females). The median age was 41 years (range 16 to 87 years), 34 (68%) had SSS. The estimated median age at first symptom onset was 33 years (95% confidence interval (CI) 29 to 43 years), range 10 to 67 years. The majority had multiple spinal levels affected. The walking distance was 110 m shorter in the SSS group (95% CI − 172 to − 40 m) as compared with the non-SSS group (p < 0.01). There was no considerable difference in hand strength between the two groups. Mean HAQ scores (0–3) for walking and hygiene were significantly higher in the SSS group, reflecting more activity limitations. Mean differences were 0.9 (95% CI 0.3 to 1.4, p < 0.01) and 0.6 (95% CI 0.2 to 1.0, p < 0.01). Pain intensity (NRS 0–10) was also significantly higher in the SSS group with a mean difference of 3.2 (95% CI 0.6 to 5.6, p = 0.02).
Main conclusions
SSS was highly prevalent in Norwegian adults with achondroplasia, with symptom onset at a young age, and multiple spinal levels affected. The presence of SSS was associated with reduced walking distance, activity limitations, and more pain. The findings underline the importance of thorough assessment and monitoring of SSS in achondroplasia, including a formal assessment of physical functioning.
References
1. Norwegian Adult Achondroplasia Study
2. Fredwall SO, Steen U, de Vries O, et al. High prevalence of symptomatic spinal stenosis in Norwegian adults with achondroplasia: a population-based study. Orphanet J Rare Dis. 2020;15(1):123. Published 2020 May 25. doi:10.1186/s13023-020-01397-6
3. Lumbar spinal stenosis, John Hopkins Medicine