Clinical Research Directory

Inclusion Criteria: Sacroiliac joint dysfunction group: * Age 18 to 50 years * Low back pain for at least 3 months, localized mainly around the posterior superior iliac spine, with or without radiation to the buttock or posterior thigh * At least three of six sacroiliac joint pain provocation tests (FABER, Gaenslen, thigh thrust, sacral thrust, compression, and distraction) positive on the same side * Foot Posture Index-6 score between 0 and +5 in both feet Healthy control group: * Age 18 to 50 years * No diagnosis of sacroiliac joint dysfunction and no related complaints (all six sacroiliac joint pain provacation tests (FABER, Gaenslen, thigh thrust, sacral thrust, compression, and distraction) negative bilaterally ) * Foot Posture Index-6 score between 0 and +5 in both feet Exclusion Criteria: * Systemic rheumatologic disease (e.g., rheumatoid arthritis, ankylosing spondylitis) * Metabolic bone disease (e.g., osteoporosis, osteomalacia) * Active lumbar disc herniation or radiculopathy * Previous fracture, surgery, or structural deformity of the lower extremity * Pregnancy * Body mass index above 30 kg/m2 * Diabetes mellitus and/or hypothyroidism * Regular exercise on more than three days per week * Occupation requiring prolonged standing (e.g., teacher, surgeon, waiter) * Walking more than 5 km per day * Physical therapy and/or injection treatment to the foot or ankle within the past 6 months * Previous diagnosis or history of plantar fasciitis * Central or peripheral nervous system disease (e.g., stroke, peripheral neuropathy, tarsal tunnel syndrome, Morton's neuroma) * Lower extremity length discrepancy of 1 cm or more * Use of orthopedic insoles, special footwear, or orthoses * History of serious foot trauma (e.g., moderate to severe ankle sprain)