REGIONAL SPECIFICITY OF DEEP FRICTION MASSAGE IN CHRONIC ACHILLES TENDINOPATHY: COMPARATIVE EFFECTIVENESS OF MUSCULOTENDINOUS JUNCTION, MID-TENDON, AND OSTEOTENDINOUS JUNCTION INTERVENTIONS - A RANDOMIZED CONTROLLED TRIAL

Background: Chronic Achilles tendinopathy presents with region-specific pathophysiological changes, yet deep friction massage (DFM) is often applied generically without considering anatomical distinctions between the musculotendinous junction (MTJ), mid-tendon (MT), and osteotendinous junction (OTJ). Purpose: To compare the immediate and 72-hour effects of region-specific DFM application on pain, function, and mechano-sensitivity in athletes with chronic mid-portion Achilles tendinopathy. Methods: Sixty competitive athletes (aged 22-45) with chronic Achilles tendinopathy were randomized into three groups: MTJ-DFM (n=20), MT-DFM (n=20), and OTJ-DFM (n=20). Each group received standardized DFM applied specifically to their assigned region. Primary outcomes included pain intensity (Visual Analog Scale), pressure pain threshold (PPT), and ankle dorsiflexion range of motion. Secondary outcomes included Victorian Institute of Sports Assessment-Achilles (VISA-A) scores and return-to-sport timeline. Measurements were taken at baseline, immediately post-intervention, and at 72 hours. Results: All groups demonstrated significant improvements in pain and function (p<0.001). MT-DFM showed superior outcomes in overall pain reduction (VAS: 6.8±1.2 to 3.1±0.8, p<0.001) and PPT improvement at the primary lesion site (28.5±4.2 to 41.7±5.3 N/cm², p<0.001). MTJ-DFM produced the greatest improvement in ankle dorsiflexion ROM (12.3±2.1° to 18.7±2.8°, p<0.001). OTJ-DFM demonstrated specific improvements at the calcaneal insertion site with superior VISA-A functional scores (47.2±8.3 to 62.8±9.1, p<0.001). Conclusions: Region-specific DFM application produces differential therapeutic effects in chronic Achilles tendinopathy. Mid-tendon DFM provides optimal pain relief at the primary degenerative site, while MTJ-DFM maximizes flexibility gains and OTJ-DFM enhances functional outcomes. These findings suggest that targeted therapeutic approaches based on anatomical and pathophysiological considerations may optimize treatment effectiveness. Clinical Relevance: Sports physical therapists should assess the predominant site of pathology and apply DFM specifically to that region to maximize therapeutic benefit and accelerate return-to-sport timelines.