Effect of Alexithymia on Response to Physical Therapy in Patients With Knee Osteoarthritis (ALEX-KOA)

Detailed Description

Knee osteoarthritis (KOA) is one of the most prevalent degenerative musculoskeletal disorders and represents a major cause of chronic pain, disability, and reduced quality of life worldwide. Although structural joint degeneration is a hallmark of the disease, increasing evidence suggests that psychological factors also contribute to pain perception, functional impairment, and variability in treatment outcomes.

Alexithymia is a personality construct characterized by difficulty in identifying, describing, and expressing emotions. Previous studies have demonstrated that alexithymia is associated with greater pain severity, poorer functional status, and unfavorable clinical outcomes in various chronic pain conditions. However, its influence on the response to conservative treatment in patients with knee osteoarthritis has not been adequately investigated.

The primary objective of this prospective observational cohort study is to evaluate whether alexithymia influences the clinical response to a standardized physical therapy program in patients with knee osteoarthritis. The secondary objective is to determine whether alexithymia independently predicts treatment outcomes after adjustment for potential confounding factors.

Patients aged 40 to 75 years with clinically and radiographically diagnosed knee osteoarthritis will be enrolled. All participants will receive a standardized physical therapy program consisting of Transcutaneous Electrical Nerve Stimulation (TENS), superficial heat therapy (hot pack), therapeutic ultrasound, and a home exercise program over a three-week treatment period.

Clinical evaluations will be performed at baseline, immediately after completion of treatment, and six weeks after treatment completion. Pain severity will be assessed using the Visual Analog Scale (VAS), functional status using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), alexithymia using the Toronto Alexithymia Scale-20 (TAS-20), and anxiety and depression using the Hospital Anxiety and Depression Scale (HADS). Participants will be classified as alexithymia-positive or alexithymia-negative according to their baseline TAS-20 scores.

The primary outcome measure will be the change in WOMAC total score. Secondary outcome measures will include changes in VAS and HADS scores. Multivariable regression analyses will be performed to determine whether alexithymia is an independent predictor of response to physical therapy after adjustment for demographic and clinical variables.