Evaluation of the shoulder complex in individuals with type 2 diabetes: A cross-sectional study

Type 2 diabetes mellitus (T2DM) can impair musculoskeletal function, affecting the shoulder's mobility, proprioception, and functional stability. Despite its growing prevalence, shoulder involvement in T2DM remains largely overlooked.

Evaluating shoulder function is essential in adults; therefore, this study aimed to investigate the biomechanical functions of the shoulder in individuals with T2DM.

Individuals with T2DM and age-matched healthy controls were evaluated for shoulder proprioception, Range of Motion (RoM), muscle strength, and functional stability. Proprioception was tested at 55°, 90°, and 125° of flexion and abduction using a laser pointer. CKCUES (Closed Kinetic Chain Upper Extremity Stability) Test and LSST (Lateral Scapular Slide Test) were also administered. Group comparisons were performed using the Mann-Whitney U test with Bonferroni correction, and ANCOVA was applied for gender and limb dominance-adjusted results.

The study compared 32 T2DM patients (age range: 50-65) and 32 healthy controls (age range: 50-65). After Bonferroni correction, significant differences in proprioception were observed only at specific angles: flexion at 125° (p = 0.001) and abduction at 90° (p = 0.005). Additionally, no statistically significant differences were observed in muscle strength parameters (p = 0.05). No differences were found in LSST. A statistically significant difference in range of motion (RoM) was observed in left abduction (p = 0.003). No muscle strength parameter remained statistically significant after Bonferroni correction (p = 0.05).

Individuals with T2DM showed impairments in proprioception and functional stability, suggesting shoulder involvement. These findings highlight the need for greater clinical attention, while rehabilitation implications should be interpreted with caution.