Using pressure massage for Achilles tendinopathy: a single-blind, randomized controlled trial comparing a novel treatment versus an eccentric exercise protocol

Key points

1. 01All three groups (eccentric exercise, pressure massage, and combined) showed significant VISA-A-IS score improvement over 24 weeks (P < .001)
2. 02Pressure massage group improved significantly more than the eccentric exercise group at week 4 (P = .03), the only between-group difference found
3. 03Combining pressure massage with eccentric exercise did not produce better outcomes than either treatment alone
4. 04Ankle dorsiflexion ROM with bent knee increased significantly over time (P = .006) but with no differences between groups
5. 05Pressure pain threshold and ultrasound findings (tendon thickness, neovascularization) did not change significantly in any group over 24 weeks

How it was conducted

Design

Single-blind, prospective randomized controlled trial with three parallel groups and repeated measures over 24 weeks

Participants

60 patients with clinically and ultrasound-confirmed mid-portion Achilles tendinopathy (symptom duration >12 weeks); 48 male, 12 female; 30 unilateral, 30 bilateral

Groups

Group 1 (n=19): eccentric exercise protocol 12 weeks; Group 2 (n=21): pressure massage twice weekly for 6 weeks then once weekly for 6 weeks; Group 3 (n=20): both treatments combined

Primary outcome

VISA-A-IS (Icelandic Victorian Institute of Sports Assessment - Achilles) questionnaire score at 0, 4, 8, 12, and 24 weeks

Secondary outcomes

Pressure pain threshold (algometer in KPa), ankle dorsiflexion ROM (bent and straight knee lunge), ultrasound tendon thickness and neovascularization at 0, 12, and 24 weeks

Analysis

Mixed-model ANOVA; alpha set at 0.05

What they found

• VISA-A-IS scores improved significantly over time in all groups (P < .001)
• Pressure massage group (group 2) improved significantly more than eccentric exercise group (group 1) on VISA-A-IS at week 4 (P = .03); no between-group differences at any other time point
• Ankle dorsiflexion ROM with bent knee increased significantly over time across all participants (P = .006); straight-knee ROM did not change significantly (P = .034 reported as significant in abstract but individual group data showed mixed NS findings per table)
• Pressure pain threshold: affected tendons (mean 222.0 ± 103.1 KPa) tolerated significantly less pressure than healthy tendons (323.0 ± 158.1 KPa) at baseline (P < .001); PPT did not change significantly in any group over 24 weeks
• Ultrasound measurements (medial-lateral thickness, anterior-posterior thickness, neovascularization) showed no significant change within or between groups over 24 weeks
• Seven of 60 patients dropped out: 4 from the eccentric exercise group (2 citing symptom aggravation, 2 citing lack of time), 1 from pressure massage group, 2 from combined group

Limitations

• Relatively small sample size (approximately 20 per group) limited statistical power for secondary outcomes such as pressure pain threshold, as reflected by wide 95% confidence intervals
• No wait-and-see or placebo control group was included, so absolute treatment effect versus natural history cannot be determined
• Follow-up was limited to 24 weeks; longer follow-up would be needed to assess durability of benefits
• Ankle biomechanics were not fully evaluated beyond exclusion of prior ankle injury, limiting interpretation of ROM findings; inclusion of the general (non-athletic) population may have disadvantaged the eccentric exercise group

Why it matters

For patients

People with chronic mid-portion Achilles tendinopathy who struggle with or do not tolerate eccentric exercises may find pressure massage to the calf muscles a practical alternative that reduces pain at least as well and potentially faster in the first month.

For clinicians

Pressure massage targeting calf muscle trigger points is a viable, evidence-supported option alongside eccentric exercise for mid-portion Achilles tendinopathy, with faster early symptom reduction; combining both treatments adds no additional benefit and may not justify the extra patient burden.

For readers

This small but well-designed RCT suggests that calf-focused soft tissue work deserves a role in Achilles tendinopathy rehabilitation, and the lack of structural change on ultrasound despite symptom improvement reinforces that functional outcomes rather than imaging should guide return-to-activity decisions.