January 12, 2010 — 根據一項發表於1月13日美國醫學會期刊（JAMA）的研究結果，相較於安慰劑，注射富含血小板的血漿（PRP），一種熱門的慢性阿基里斯腱疾患或是肌腱病變治療方式，顯然無法降低疼痛或增加運動活性。
荷蘭鹿特丹Erasmus大學醫學中心的Robert J. de Vos醫師與其同事們寫到，最近三項綜論報告使用PRP於肌腱病變的效果卓越，儘管這些結論是根據實驗室研究，以及有重要限制的臨床研究。雖然我們沒有有關使用這個治療方法的盛行率數據，但最近發表的兩項綜論指出注射PRP治療肌腱病變在臨床上越來越常見。
這項雙盲、隨機分派、安慰劑控制研究合併PRP與安慰劑注射生理食鹽水，配合離心運動。研究對象是54位年齡介於18~79歲的病患，這些病患在2008年8月到2009年1月之間於荷蘭萊岑丹Antoniushove Hague醫學中心就診，罹患中段阿基里斯腱肌腱病變。他們採用一種問卷（Victorian Institute of Sports Assessment-Achilles[VISA-A]）來評估試驗開始時，以及第6、12與24週時的疼痛與運動活性。
Trendy Chronic Achilles Tendon Injury Therapy Is Ineffective
By Nancy Fowler Larson
Medscape Medical News
January 12, 2010 — Injections of platelet-rich plasma (PRP), an up-and-coming treatment for chronic Achilles tendon disorder, or tendinopathy, does not appear to reduce pain or increase activity more than placebo, according to a study published in the January 13 issue of the Journal of the American Medical Association.
"Three recent reviews reported promising results of the use of PRP in tendinopathy, although these conclusions were based on laboratory studies and on clinical studies with important limitations," write Robert J. de Vos, MD, from the Department of Orthopedics, Erasmus University Medical Center, Rotterdam, the Netherlands, and colleagues. "Although we are unaware of published data on the prevalence of use of this therapy, 2 recent reviews have suggested that PRP injections for tendinopathy are increasingly used in the clinical setting."
Tendon disorders in the Achilles heel and other locations make up 30% to 50% of all sports injuries, can lead to long interruptions in sports participation, and often interfere with daily life.
This double-blind, block randomized, placebo-controlled trial combined both PRP and placebo saline injections with eccentric exercises. Researchers studied 54 patients, ages 18 to 79 years, who had midportion Achilles tendinopathy at The Hague Medical Center Antoniushove, Leidschendam, the Netherlands, between August 2008 and January 2009. They employed a questionnaire (Victorian Institute of Sports Assessment-Achilles [VISA-A]) to measure pain and activity at the study's onset and at 6, 12, and 24 weeks.
Making a prediction based on previous studies, the authors hypothesized that the VISA-A score of the PRP group would be 12 points higher than that of the placebo group. However, their findings proved otherwise.
Results after 24 weeks showed that for the PRP group, the mean VISA-A score improved by 21.7 points (95% confidence interval [CI], 13.0 - 30.5). The placebo group's score increased by 20.5 points (95% CI, 11.6 - 29.4). After adjustment for variables, including the baseline VISA-A score (P = .03) and duration of symptoms (P = .06), there was no significant distinction between the 2 groups during any measurement period. Between-group variations were 2.5 (95% CI, ?6.9 to 11.9) at 6 weeks, ?1.6 (95% CI, ?11.9 to 8.7) at 12 weeks, and ?0.9 (95% CI, ?12.4 to 10.6) at 24 weeks. Positive values favor the PRP group.
Furthermore, no significant differences were seen in secondary outcome measures. These include subjective patient satisfaction (after 24 weeks, ?4.1%; 95% CI, ?25.8% to 17.7%) and the number of patients returning to their sport (after 24 weeks, 1.4%; 95% CI, ?17.0% to 19.8%). Again, positive values favor the PRP group. Neither were there any important differences between the groups in terms of exercise compliance.
"The reason why both treatment groups show clinical progression in our study, but also in other studies on PRP, is likely due to the fact that exercises were performed. Eccentric exercises have been shown to be effective in previous randomized trials," the authors write.
The study authors reported 2 limitations: numbers could not be established for the amount of platelets and activated growth factors in the PRP injections, and the absence of a group receiving PRP injection but no eccentric exercises prohibited the study from determining whether exercise actually has a negative effect on PRP therapy.
The authors recommended further investigation of injections to remedy tendinopathy, formerly known as tendinitis. They also noted the importance of finding effective treatments that do not involve injections.
"Conservative treatment is disappointing and 25% to 45% of patients eventually require surgery," the authors write. "There is a clear need for improved conservative therapy."
Biomet Biologics LLC supported the study. The study authors have disclosed no relevant financial relationships.
