Does Combining PRP with Shockwave Therapy Improve Collagen Quality in Tendon Healing?

Tendons are notoriously slow to heal due to low vascularity and limited cellular turnover. For chronic tendinopathies, improving not just pain, but the quality and organisation of collagen fibres, is key to restoring function and preventing reinjury. Recent research suggests that combining platelet-rich plasma (PRP) injections with focused extracorporeal shockwave therapy (fESWT) may offer synergistic benefits.

How PRP and Shockwave Target Collagen Remodelling

1. PRP: Growth Factor Therapy

• PRP is rich in platelets, cytokines, and growth factors such as PDGF, TGF-β, and VEGF.

• These factors stimulate fibroblasts, encouraging the deposition of type I collagen, which is stronger and more aligned than the disorganised type III collagen found in chronic tendinopathy.

2. Focused Shockwave Therapy (fESWT): Mechanical Stimulus

• fESWT delivers high-energy acoustic waves to the tendon, promoting:

  • Neovascularisation (new blood vessel formation)

  • Cellular proliferation

  • Collagen fibre realignment

• fESWT also modulates pain via nociceptor desensitisation, allowing patients to engage in rehabilitation exercises that reinforce tendon remodelling.

Evidence from Clinical and Imaging Studies

1. Ultrasound and MRI Findings

   • Studies show that tendons treated with PRP + fESWT demonstrate improved echotexture, thicker collagen bundles, and more uniform fibre alignment.

   • Collagen organisation correlates with functional improvements and reduced pain.

2. Comparison to Single Modality

   • PRP alone improves growth factor signalling, but mechanical stimulation may be insufficient.

   • Shockwave therapy alone can improve vascularity and pain but may not maximise fibroblast activity.

   • Combined therapy addresses both biochemical and biomechanical pathways, offering the best environment for collagen maturation and tendon resilience.

3. Tendon Types Studied

   • Evidence is strongest for:

     • Achilles tendinopathy

     • Patellar tendinopathy

     • Lateral epicondylitis (tennis elbow)

   • Early reports suggest similar benefits may extend to rotator cuff and hamstring tendinopathies.

Practical Considerations

• Timing:

  • Some protocols use shockwave therapy before PRP, others after—both appear safe, with minor differences in collagen remodelling rates.

• Sessions and Dosing:

  • fESWT: 1–3 sessions spaced weekly

  • PRP: typically a single injection or up to 3 injections depending on tendon size and chronicity

• Rehabilitation Integration:

  • Collagen remodelling is activity-dependent. Pain reduction from fESWT allows earlier load progression, strengthening, and mobility work, which further supports tendon fibre alignment.

• Patient Expectations:

  • Improvement in pain may be noticed within weeks, but collagen remodelling and structural tendon improvement can take 3–6 months.

Combining PRP and focused shockwave therapy addresses both biological and mechanical aspects of tendon healing, promoting higher-quality collagen deposition and better fibre alignment. While more large-scale RCTs are needed, current evidence suggests this combination can:

• Accelerate structural repair

• Reduce pain more effectively than either therapy alone

• Improve functional outcomes

• Support long-term tendon resilience and reduced reinjury risk