Effectiveness of reducing tendon compression in the rehabilitation of insertional Achilles tendinopathy

Key points

1. 01Low tendon compression rehabilitation (LTCR) improved VISA-A scores by 24.4 points at 12 weeks versus 12.2 points for high compression rehabilitation (HTCR), a between-group difference of 12.9 points (95% CI: 6.2 to 19.6, p<0.001).
2. 02At 24 weeks the between-group difference was 10.4 points (95% CI: 3.7 to 17.1, p=0.003), still exceeding the minimal clinically important difference of 10 points.
3. 03Patient satisfaction at 24 weeks was 94.7% in the LTCR group versus 57.9% in the HTCR group (p=0.009).
4. 04Return to desired sport at 12 weeks was 94.7% in the LTCR group versus 68.4% in the HTCR group (p=0.045).
5. 05LTCR also produced a significant reduction in Achilles tendon anteroposterior diameter at 24 weeks, while no significant change was seen in the HTCR group.

How it was conducted

Design

Investigator-blinded, stratified, parallel-group randomised clinical trial

Participants

42 sport-active adults (30 male, 12 female; mean age 45.8 years) with chronic (>3 months) insertional Achilles tendinopathy and VISA-A score below 80

Groups

LTCR (n=20): progressive 4-stage tendon loading with ankle dorsiflexion limited, no calf stretching, and heel lifts; HTCR (n=22): identical loading progression but exercises performed in end-range ankle dorsiflexion with calf stretching

Duration

12-week supervised programme with 24-week total follow-up

Primary outcome

VISA-A score (0-100, higher = better) at 12 and 24 weeks, analysed by intention-to-treat linear mixed model

Setting

Ghent University Hospital Sports Medicine department, Belgium (November 2022 to December 2023)

What they found

• LTCR VISA-A increased from 59.8 (95% CI: 55.1 to 64.4) at baseline to 84.2 (95% CI: 79.6 to 88.9) at 12 weeks and 88.8 (95% CI: 84.2 to 93.5) at 24 weeks.
• HTCR VISA-A increased from 59.1 (95% CI: 54.4 to 63.7) at baseline to 71.3 (95% CI: 66.7 to 76.0) at 12 weeks and 78.4 (95% CI: 73.8 to 83.1) at 24 weeks.
• Between-group VISA-A difference at 12 weeks: 12.9 points (95% CI: 6.2 to 19.6; p<0.001).
• Between-group VISA-A difference at 24 weeks: 10.4 points (95% CI: 3.7 to 17.1; p=0.003).
• VAS-HOP between-group difference at 12 weeks: -15.0 mm (95% CI: -25.0 to -4.9; p=0.004) and at 24 weeks: -12.0 mm (95% CI: -22.1 to -1.9; p=0.020) in favour of LTCR.
• VAS-ADL between-group difference at 12 weeks: -10.0 mm (95% CI: -19.5 to -0.5; p=0.038) and at 24 weeks: -10.4 mm (95% CI: -19.9 to -1.0; p=0.030) in favour of LTCR.
• Achilles tendon anteroposterior diameter decreased significantly in LTCR (p<0.001 over 24 weeks) but not in HTCR (p=0.729).
• Exercise adherence was comparable: LTCR 82% versus HTCR 84% (p=0.567).
• No adverse events were reported in either group during the trial.
• Loss to follow-up was 9.5% overall (1 in LTCR, 3 in HTCR).

Limitations

• The individual contribution of each LTCR component (heel lifts, restricted dorsiflexion, calf massage) cannot be separated, so the optimal treatment elements remain undefined.
• Participants could not be blinded to their intervention, which may have introduced bias in patient-reported outcomes such as the VISA-A.
• The sample was restricted to sport-active adults with chronic symptoms, limiting generalisability to sedentary patients or those with acute or reactive presentations.
• The lower bounds of the 95% confidence intervals for between-group VISA-A differences fell below the 10-point minimal clinically important difference, reflecting some uncertainty about the magnitude of the treatment effect.

Why it matters

For patients

Athletes with Achilles pain at the heel bone insertion can expect meaningfully better pain relief and a faster return to sport when their rehabilitation avoids ankle dorsiflexion end range and includes heel lifts.

For clinicians

This RCT provides the first controlled evidence supporting compression-reducing exercise protocols for insertional Achilles tendinopathy, recommending restriction of ankle dorsiflexion during loading, substitution of calf massage for stretching, and commercially available heel lifts.

For readers

The study fills a key evidence gap by confirming a mechanistically plausible but previously unproven clinical recommendation, though the inability to isolate individual protocol components limits precision prescription.