Intratendinous injection of platelet-rich plasma under US guidance to treat tendinopathy: a long-term pilot study.

PURPOSE: To assess the potential therapeutic effect of intratendinous injection of platelet-rich plasma (PRP) under ultrasound (US) guidance to treat tendon tears and tendinosis in a pilot study with long-term follow-up. MATERIALS AND METHODS: The study included 408 consecutive patients referred for treatment by PRP injection of tendinopathy in the upper (medial and lateral epicondylar tendons) and the lower (patellar, Achilles, hamstring and adductor longus, and peroneal tendons) limb who received a single intratendinous injection of PRP under US guidance. Clinical and US data were retrospectively collected for each anatomic compartment for upper and lower limbs before treatment (baseline) and 6 weeks after treatment. Late clinical data without US were collected until 32 months after the procedure (mean, 20.2 months). The McNemar test and regression model were used to compare clinical and US data. RESULTS: QuickDASH score, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score, and residual US size of lesions were significantly lower after intratendinous injection of PRP under US guidance at 6 weeks and during long-term follow-up compared with baseline (P < .001 in upper and lower limb) independent of age, gender, and type of tendinopathy (P > .29). No clinical complication was reported during follow-up. CONCLUSIONS: Intratendinous injection of PRP under US guidance appears to allow rapid tendon healing and is well tolerated.

Acceleration of tendon healing using US guided intratendinous injection of bevacizumab: first pre-clinical study on a murine model.

PURPOSE: Tendinopathy shows early disorganized collagen fibers with neo-angiogenesis on histology. Peri-tendinous injection of corticosteroid is the commonly accepted strategy despite the abscence of inflammation in tendinosis. The aim of our study was to assess the potential of intratendinous injection of an anti-angiogenic drug (bevacizumab, AA) to treat tendinopathy in a murine model of patellar and Achilles tendinopathy, and to evaluate its local toxicity. MATERIALS AND METHOD: Forty rats (160 patellar and Achilles tendons) were used for this study. We induced tendinosis (T+) in 80 tendons by injecting under ultrasonography (US) guidance Collagenase 1(®) (day 0 = D0, patellar = 40 and Achilles = 40). Clinical examination and tendon US were performed at D3, immediately followed by either AA (AAT+, n = 40) or physiological serum (PST+, n = 40, control) US-guided intratendinous injection. Follow-up at D6 and D13 using clinical, US and histology, and comparison between the 2 groups were performed. To study AA toxicity we compared the 80 remaining normal tendons (T-) after injecting AA in 40 (AAT-). RESULTS: All AAT+ showed a better joint mobilization compared to PST+ at D6 (p = 0.004) with thinner US tendon diameters (p<0.004), and less disorganized collagen fibers and neovessels on histology (p<0.05). There was no difference at D13 regarding clinical status, US tendon diameter and histology (p>0.05). Comparison between AAT- and T- showed no AA toxicity on tendon (p = 0.18). CONCLUSION: Our study suggests that high dose mono-injection of AA in tendinosis, early after the beginning of the disease, accelerates tendon's healing, with no local toxicity.