Michael Maioirno, D.C.

Shockwave therapy at the tendon insertion — a clinical brief The neovascular cascade behind ESWT, from Wang et al. (2003)

In a rabbit Achilles tendon–bone junction model, a single ESWT session (500 impulses, 0.12 mJ/mm²) produced a time-dependent neovascular response. Angiogenic signalling (eNOS, VEGF) rose by week 1 and stayed elevated to week 8, returning to baseline by week 12. Endothelial proliferation (PCNA) and neo-vessel counts rose from ~week 4 and persisted to 12 weeks and beyond. 

The timeline in numbers 

Week 1 eNOS, VEGF and PCNA all rise (~2× control). Neo-vessel count not yet significantly increased.

Week 4 Angiogenic signaling peaks; neo-vessel increase now statistically significant.

Week 8 eNOS/VEGF still elevated; vessels and proliferation sustained. 

Week 12 eNOS/VEGF back to baseline (transient); PCNA and neo-vessels remain elevated (durable).

Clinical relevance 

Transient signal, durable structure. A brief angiogenic trigger drives a lasting vascular response — consistent with clinical benefit appearing ~4 weeks post-treatment, and an argument for completing the course. Honest boundary. PCNA here reflects endothelial (vessel-building) proliferation, not tendon collagen. Sustained tendon-tissue repair is a reasonable downstream inference the authors draw, not a directly measured endpoint. 

Human signal. In insertional Achilles tendinopathy, ultrasound neovascularization at 4 weeks has been shown to track clinical (VISA-A) improvement — bridging this bench model toward the clinic. 

Reference & further reading 

Wang C-J, Wang F-S, Yang KD, et al. Shock wave therapy induces neovascularization at the tendon–bone junction: a study in rabbits. J Orthop Res. 2003;21(6):984–989. 

https://doi.org/10.1016/S0736-0266(03)00104-9 

Biological response of ESWT to tendinopathy in vivo — open-access review. 

https://pmc.ncbi.nlm.nih.gov/articles/PMC9356378/ 

Ultrasonography in insertional Achilles tendinopathy — neovascularization at 4 weeks tracks clinical improvement. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5149604/ 

Educational summary · Wang et al., J Orthop Res 2003;21:984–989 · for information only, not a substitute for clinical judgement