SLR - May 2014 - Amanda Quisno
Prospective, Randomized, Blinded, Comparative Study of Injectable Micronized Dehydrated Amniotic/Chorionic Membrane Allograft for Plantar Fasciitis—A Feasibility Study
Reference: Zelen CM, Poka A, Andrews J. Prospective, Randomized, Blinded, Comparative Study of Injectable Micronized Dehydrated Amniotic/Chorionic Membrane Allograft for Plantar Fasciitis—A Feasibility Study. Foot & Ankle International, 34(10): 1332-1339, 2013.
Scientific Literature Review
Reviewed By: Amanda Quisno, DPM
Residency Program: Grant Medical Center
Podiatric Relevance: Plantar fasciitis is one of the most common complaints encountered by podiatric physicians, affecting more than 1 million persons per year, with an estimated annual burden of $192 to $376 million to the United States health care system. Treatments vary from conservative, including rest, stretching exercises, orthotics, oral anti-inflammatories, cryotherapy and corticosteroid injections, to more advanced including extracorporeal shock wave therapy or plantar fasciotomy. Plantar fasciitis is characterized by classic signs of inflammation such as pain, swelling, and loss of function, and although non-operative management leads to resolution of these symptoms in ~90 percent of patients, the condition can be challenging and frustrating to treat, taking several months to even years before symptoms are relieved. During this time the plantar fascia undergoes a degenerative process from repetitive micro-tearing and the pain can become more and more resistant to non-operative management. In vitro and in vivo studies have shown human amniotic membrane to have biochemical properties which help reduce inflammation and enhance soft tissue healing. It contains growth factors which can help stimulate epithelial cell migration and proliferation, as well as general protein and collagen synthesis, collagenase activity, and chemotaxis of fibroblasts and smooth muscle cells. Dehydrated human amniotic chorionic membrane has recently been refined with a micronization process to a powder form which can be dispersed into a sterile saline solution and injected. This randomized, controlled trial was designed to evaluate the feasibility of using micronized dehydrated human amniotic/chorionic membrane (mDHACM) in suspension in 0.9 percent saline solution as an injectable treatment for plantar fasciitis.
Methods: A total of 45 patients with plantar fasciitis of eight weeks to one year duration which had not responded to traditional therapy were included. Patients were randomized into one of three groups, each including standard care plus either (1) 2 injections (2 cc of 0.5 percent marcaine plain, then 1.25 cc sterile 0.9 percent saline, (2) 2 injections (2 cc of 0.5 percent marcaine plain, then 0.5 cc of mDHACM injectable) (0.5 cc mDHACM groups, or (3) two injections (2 cc of 0.5 percent Marcaine plain, then 1.25 cc of mDHACM injectable (1.25 cc mDHACM group). Randomization was balanced with 15 patients in each group. The physician administering the injections and performing follow-up exams was not blinded, however, patients were blinded as to which treatment they received. Follow-up after intervention was scheduled weekly for six weeks, with a final study visit eight weeks post-injection. All patients also were prescribed Tramadol 50 mg to be taken as needed for pain associated with the injection. Patients were all instructed on use of a daytime CAM boot and night splint for the first 2 weeks after the injection, after which they could return to tennis shoes with an over-the counter orthotic. Three difference scales were used to evaluate symptom improvement: the American Orthopaedic Foot and Ankle Society Hindfoot Scale, The Wong-Baker FACES Pain Rating Scale, and QualityMetric’s SF-36v2 Standard Health Survey.
Results: In the 45 patients meeting inclusion criteria, the mean duration of symptoms prior to initializing treatment was 21.8 ± 12.0 weeks. Significant improvement was seen in patients receiving both 0.5 cc and 1.25 cc of mDHACM versus controls within one week of treatment. For the control group, within one week of treatment AOFAS Hindfoot scores increased by a mean of 2.2 ± 17.4 points, versus 38.7 ± 11.4 of the 0.5 cc mDHACM groups and 33.7 ± 14.0 for the 1.25 cc mDHACM group. Within each group AOFAS scores were also higher between baseline and week eight, with significantly greater improvement noted in the mDHACM groups. Additionally, FACES pain rating scored improved significantly, with the median reduction in pain being three points for controls, and six and five points for the 0.5 cc and 1.25 cc mDHACM groups, respectively. Functional health and well-being measured using QualityMetric’s SF-37v2 Standard Health Survey showed no difference between baseline and study conclusion for controls, while both mDHACM groups showed significant improvement at study completion for both physical and mental well-being.
Conclusions: Treatment groups showed significantly more clinical improvement versus controls at eight week follow-up utilizing multiple outcome measures. The results of this clinical trial show that mDHACM allograft injection is an effective treatment for patients with chronic plantar fasciitis.