Effect of Eccentric Exercise Program for Early Tibialis Posterior Tendinopathy

Background: Morphology and vascularization of painful tibialis posterior (TP) tendons before and after an intervention targeting the degenerated tendon were examined. Functional status and pain level were also assessed. Materials and Methods: A 10-week twice daily, progressive eccentric tendon loading, calf stretching program with orthoses was implemented with ten, early stage TP tendinopathy subjects. TP tendons were imaged by grayscale and Doppler ultrasound at INITIAL and POST evaluations to assess the tendon's morphology and signs of neovascularization. The Foot Functional Index (FFI), Physical Activity Scale (PAS), 5-Minute Walk Test, and single heel raise (SHR) test were completed at INITIAL and POST evaluations. The Global Rating Scale (GRS) was completed at 6 months followup. One-way ANOVA was used to compare the FFI at INITIAL, POST, and 6-MONTH time points. Paired t-tests were used to compare means between the remaining variables. The level of significance was p = 0.05. Results: There was a significant difference in FFI total, pain, and disability at the three time-points. Post-hoe paired t-tests revealed that the FFI scores were lower for the total score and pain and disability subcategories when comparing from INITIAL to POST and INITIAL to 6-MONTH evaluations (p < 0.05 for all). The number of SHR increased significantly on the involved side from INITIAL to POST evaluation (p = 0.041). The GRS demonstrated minimum clinically important differences for improvements in symptoms at 6-MONTH. Tendon morphology and vascularization remained abnormal following the intervention. Conclusion: A 10-week tendon specific eccentric program resulted in improvements in symptoms and function without changes in tendon morphology or neovascularization.