1033 - Risk of Lumbar Degenerative Disc Disease Associated with Competitive Swimming: A Systematic Review and Meta-Analysis

Objectives: The purpose of the current study is to synthesize the outcomes of investigations reporting the odds of lumbar degenerative disc disease (DDD) in high-intensity swimmers compared to controls.

Design: We conducted searches of PUBMED, EMBASE, and Web of Science databases according to PRISMA guidelines from inception until March 2023 to identify relevant studies evaluating the risk for lumbar DDD associated with swimming. We performed meta-analysis using random-effects models to synthesize the odds ratios for positive imaging findings of DDD at one or more lumbar level in swimmers compared to non-swimmers, as well as the prevalence of lumbar disc degeneration and the prevalence of back pain.

Results: Four studies were included in the final analysis. Study quality and risk of bias were deemed adequate. There was significant heterogeneity among studies (I² =0.74). Swimmers did not demonstrate greater odds of lumbar DDD than controls (OR: 2.15, 95% CI: 0.96-4.85, p=0.06). However, swimmers demonstrated greater odds of degenerated discs across all lumbar disc levels (OR: 1.85, 95% CI: 1.12-3.05). The pooled prevalence estimate of lumbar DDD was 59% in swimmers and 42% in controls. Secondary outcome analysis indicated that swimmers have a higher probability of developing moderate-to-severe back pain than controls (OR: 2.36, 95% CI: 1.33-4.16).

Conclusions: High-load swimming was not significantly associated with presence of DDD on advanced imaging. However, high-load swimming was associated with multilevel disc degeneration and moderate-to-severe pain. Although swimming is considered a low impact sport, elite swimmers risk developing lower back pain and disc pathology, possibly because training involves unique biomechanics with repetitive rotational and hyperextension/flexion of the spine. The present study is limited by a low number of included studies that were highly heterogeneous. Further research investigating risk factors involving biomechanics of swimming on the spine may have important implications for stroke technique, injury prevention, and rehabilitation for swimmers.