Background There are limited data on scoliosis in cystic fibrosis (CF) and the two most recent studies came to opposite conclusions. Reported prevalence ranges from 2%¹ (within the normal range for the general population: 0.5–3.2%) to 15.5%.² We felt that a recent study under-estimated the prevalence due to a very young population (median age 10.9 years), since scoliosis is most common in adolescents. We hypothesised that scoliosis is more prevalent in adolescents with CF compared to the general population.

Objective To determine the incidence of scoliosis in adolescents with CF, and describe the spinal deformities.

Population Patients in our CF clinic aged >10 years, and those who have transitioned to adult services in the last 10 years.

Methods We conducted a retrospective observational study. Most recent chest radiographs, or those taken at transition to adult services, were reviewed by a Consultant Radiologist. Scoliosis was defined as a Cobb angle of greater than 10 degrees in the coronal plane.³

Results Our sample size was 143 CF subjects (48% male) with a median age at the time of chest radiograph of 18 years (range 10–18 years). 16 (6 male) subjects were noted to have scoliosis with a median (range) Cobb angle of 14 (10–38) degrees giving a prevalence of 11%. 13 were single curves, 2 double and 1 triple. The majority were short mid-thoracic curves, with the apex to the right.

Conclusion We found a prevalence of scoliosis in a predominantly adolescent CF population that is significantly greater than expected in the general population. The negative effect of scoliosis on lung function is well-documented. With the progressive nature of CF lung disease, scoliosis may have further deleterious effects. Bone disease is increasingly recognised in CF patients, with osteopenia and osteoporosis occurring earlier and more frequently than in the general population (38% & 24% respectively in 18–32 year old CF patients).⁴ To date, studies have failed to show a correlation between scoliosis, lung function and bone mineral density.

The paradigm of a radiologically significant (Cobb angle >10 degrees) versus a clinically important scoliosis remains.

References

1. Fainardi V, Koo SD, Padley SP, Lam SH, Bush A. Prevalence of scoliosis in cystic fibrosis. Pediatr Pulmonol 2013 Jun;48(6):553-555.

2. Kumar N, Balachandran S, Millner PA, Littlewood JM, Conway SP, Dickson RA. Scoliosis in cystic fibrosis: is it idiopathic? Spine (PhilaPa 1976) 2004;29:1990–1995.

3. Scoliosis Research Society criteria, www.srs.org

4. Quon BS, Aitken ML. Cystic fibrosis: what to expect now in the early adult years. Paediatr Respir Rev. 2012;13(4):206-214.