Physical Function in Amateur Athletes with Lumbar Disc Herniation and Chronic Low Back Pain: A Case-Control Study

This study aimed to analyze if chronic low back pain (LBP) and lumbar disc herniation induce biomechanics, flexibility, body balance, physical activity, and muscular function alterations compared to a similar asymptomatic cohort. Fifty male volunteers (n = 25 with chronic LBP and lumbar disc herniation and n = 25 pain-free subjects) were enrolled. Range of motion (internal and external hip rotation, ankle dorsiflexion, and active straight leg raise, ASLR), trunk flexibility (finger–floor distance), body balance (Y-balance test) and muscle function (Biering–Sorensen test, prone and lateral bridges) outcomes were assessed. Comparative analyses between sides and group were conducted. Results: Patients showed greater weight and BMI compared with controls (p < 0.05). None of the outcomes bilaterally assessed showed side-to-side differences for pain-free participants (all, p > 0.05) or LBP patients (all, p > 0.05). Regarding the differences between groups, LBP patients showed limited internal hip rotation (p < 0.001), finger–floor distance (p < 0.001), body balance (p < 0.001), and muscle endurance (planks p < 0.001; Biering–Sorensen test p < 0.05). External hip rotation, ASLR, and ankle dorsiflexion range of movement were comparable in both groups (p > 0.05). The sample of pain-free amateur athletes showed greater range of movement for internal hip rotation, lower finger–floor distance, better body balance, and muscle function. However, the external hip rotation, ankle dorsiflexion, and ASLR tests showed no difference between cases and controls.