Effects of Kinesio taping on chronic midportion Achilles tendinopathy pain and pain-free isometric plantar flexion strength: a multiple participant single-subject experimental study design

Background/Aims Achilles tendinopathy is a common musculoskeletal pathology. Despite widespread use of Kinesio taping for treating chronic midportion Achilles tendinopathy, sparse and primarily low-level evidence supports its use. The aim of this study was to determine the effectiveness of Kinesio taping in improving pain-free plantar flexion strength and pain during functional tendon loading activities. Methods A multiple participant, single-subject experimental design, using an A-B-A-B-A format over 5 consecutive days was implemented. The manipulated variable was Kinesio taping application: standardised, therapeutic Kinesio taping (B) was compared to no tension, sham Kinesio taping (A) in three participants with chronic midportion Achilles tendinopathy. Outcome variables, derived from the VISA-A Questionnaire, included pain scores measured by a visual analogue scale during a 30-foot walk, stair descent, and 10 single-leg heel raises. Pain-free ankle plantar flexion strength was also measured using a handheld dynamometer. Results For participant 1, visual analogue scale pain scores decreased by 3, 13 and 16 points respectively for the 30-foot walk (day 1: 7; day 5: 4), single-leg heel raises (day 1: 25; day 5: 12) and stair descent (day 1: 20; day 5: 4). Pain-free plantar flexion isometric force increased by 7.7 kg (day 1: 29.5 kg; day 5: 37.2 kg). Participant 2 did not exhibit any meaningful overall changes in visual analogue scale pain scores for any of the three testing activities (30-foot walk test: day 1: 7; day 5: 8, stair descent: day 1: 8; day 5: 15, and single leg heel raises: day 1: 14; day 5: 11, or pain-free plantar flexion isometric force (day 1: 42.2 kg; day 5: 34.9 kg). For participant 3, visual analogue scale pain scores decreased by 36, 65 and 70 points respectively for the 30-foot walk (day 1: 47; day 5: 11), single-leg heel raises (day 1: 90; day 5: 25) and stair descent (day 1: 80; day 5: 10). Pain-free plantar flexion isometric force increased by 28.1 kg (day 1: 15.5 kg; day 5: 43.6 kg). Fluctuations in outcome measures did not occur when comparing therapeutic and sham Kinesio taping in any of the participants. Conclusions Kinesio taping resulted in overall improvements in pain and plantar flexion strength in two participants, perhaps indicating that the ‘therapeutic’ effects of Kinesio taping are not dependent on tape tension in certain individuals. Although this is the first experimentally designed study exploring the effectiveness of Kinesio taping on chronic midportion Achilles tendinopathy symptoms, the authors intend for the methodology and results to guide future, more rigorous experimentally designed research. Implications for practice This study supports the cumulative effects of Kinesio taping in lessening chronic, midportion Achilles tendinopathy pain during tendon loading activities in individuals with a healthy body mass index. Clinicians may consider the use of Kinesio tape as a short-term intervention aimed at improving tolerance to functional activities and therapeutic exercise.