Diabetes mellitus is a chronic metabolic disorder associated with systemic complications, including musculoskeletal abnormalities affecting the foot and ankle. These complications can lead to gait disturbances, altered plantar pressure distribution, increased risk of ulceration, and functional limitations that reduce quality of life. The present study aimed to examine foot and ankle musculoskeletal abnormalities among diabetic patients and explore their relationship with neuropathy and duration of diabetes. A cross-sectional analytical study was conducted among diabetic patients attending tertiary care hospitals in Peshawar, Pakistan. Using convenience sampling, 120 individuals diagnosed with Type 1 or Type 2 diabetes mellitus were recruited. Musculoskeletal assessment included measurement of ankle range of motion using a universal goniometer, evaluation of foot posture using the Foot Posture Index-6, pain assessment with the Numeric Pain Rating Scale, and neuropathy screening using the Michigan Neuropathy Screening Instrument. Data were analyzed using descriptive and inferential statistics with SPSS version 26. The results demonstrated reduced ankle range of motion among participants, with mean dorsiflexion of 14.2° (SD = 4.3) and plantarflexion of 36.8° (SD = 6.1). Neuropathy showed a significant association with foot deformities (χ² = 8.72, p = 0.003), particularly hallux valgus and claw toe deformities. Neuropathy scores were moderately correlated with pain intensity (r = 0.51, p < 0.001), while duration of diabetes showed a negative correlation with ankle range of motion (r = −0.42, p = 0.001). These findings highlight the importance of early musculoskeletal screening and physiotherapy interventions in diabetic care to prevent foot complications.