SLR - February 2018 - Vikram A. Bala
Reference: Boesen AP, Hansen R, Boesen MI, Malliaras P, Langberg H. Effect of High-Volume Injection, Platelet-Rich Plasma, and Sham Treatment in Chronic Midportion Achilles Tendinopathy: A Randomized Double-Blinded Prospective Study. Am J Sports Med. 2017:363546517702862.Scientific Literature Review
Reviewed By: Vikram A. Bala, DPM
Residency Program: UF Health Jacksonville, Jacksonville, FL
Podiatric Relevance: Achilles tendinopathy(AT), a common overuse injury, is often chronic and difficult to manage. It presents as pain, swelling and inability to perform strenuous activity caused by repeated overloading. Pathology is often found in the midportion of the tendon and grows painful due to in growth of new vessels and group III/IV nerves, along with chronic degeneration and microtears of the tendon. This increase of nerves and vessels in the ventral aspect of the tendon adjacent to Kager’s triangle is believed to be the main pain generator in AT. No gold standard exists for treatment of AT, but it is widely accepted that progressive tendon loading with eccentric training aids recovery. Alternatively, load modification, analgesics, NSAID therapy, ice therapy, manual therapy, biomechanical correction, shockwave therapy, injections and surgery have been considered. However, there are few randomized, prospective trials for clinical in-office treatment options for AT. This study aims to compare the pain and functional outcome of high-volume injections (HVI), a series of platelet-rich plasma (PRP) injections and placebo injections, with eccentric training for patients with chronic midportion AT.
Methods: Level 1, double-blind, randomized control trial was performed at the Institute of Sports Medicine, Copenhagen, Denmark. Sixty males with chronic AT were followed for six months. Participants performed eccentric training with either one HVI injection, a series of four PRP injections q14 days or a placebo treatment. Intervention for all groups was done utilizing ultrasonography, with patient in the prone position. HVI therapy consisted of a mixture of 10ml of 0.5 percent bupivacaine hydrochloride and ~20 mg of Depo-Medrol, injected, followed by four flushes of 10 ml of normal sterile saline. Four ml of PRP was used for each PRP injection. For placebo, 4 ml of isotonic saline was injected. Patients were randomized by age, function and symptoms. Outcomes included function and symptoms (VISA-A), with visual analog pain scale (VAS), tendon thickness and intratendinous vascularity (ultrasound) and muscle function (heel-rise test). Outcomes were assessed at zero, six, 12 and 24 weeks.
Results: VISA-A scores improved in all groups at each follow-up, and improvements were significantly greater in the HVI versus the PRP group and placebo group at both six and 12 weeks. At 24 weeks, HVI and PRP groups had significantly greater improvements than the placebo group. VAS scores improved in all groups, with greater decrease in HVI and PRP groups versus placebo. Tendon thickness had significant decrease in only HVI and PRP groups during intervention. Thickness had greatest decrease in HVI versus PRP and placebo groups at six and 12 weeks, and in HVI and PRP groups versus placebo group at 24 weeks. Muscle function improved with no differentiation across the board.
Conclusion: HVI regimen may be more effective in improving short-term clinical outcomes of chronic AT than PRP per statistical significance at six and 12-week follow-ups, with no significant difference in the medium term. Treatment with HVI or PRP with a 12-week eccentric training regimen seems more effective in reducing pain, improving activity levels and decreasing tendon thickness and intratendinous vascularity than just eccentric training alone.