Off-loading 減壓- RCW

游朝慶 醫師

  儘管全接觸式石膏TCC的治療已在糖尿病足部潰瘍的治療指引列為黃金標準(詳見前文)，美國芝加哥吳姓足部女醫師等人¹研究調查全美國895個足部治療中心發現僅僅只有1.7%會使用TCC，有15.2%使用removable cast walker(RCW，可拆式助行鞋，又稱CAM Walker，CAM代表“Controlled Ankle Movement”限制腳踝活動)，有12.3的中心使用complete non-weight-bearing(NWB，全不著力)策略，如使用拐杖及輪椅，而最多使用的是shoe modification(特製鞋或鞋墊)，佔41.2%，儘管過去的研究顯示這並不是一個最有效的減壓方式²。為何明知道TCC有特效，但人們卻又不願意使用它呢？Piaggesi³認為原因在於安裝TCC需要訓練，一般醫師不知道如何正確打上石膏才不會受傷，安裝時間需要花20-30分鐘，以及患者需要頻繁回診換石膏，這也導致需要額外的花費。

Air Walker removable cast walker，£44.99，http://www.physioroom.com/product/PhysioRoom.com_Air_Walker_Ankle_and_Foot_/2247/38721.html

Aircast SP Walking Brace，$84.99
http://www.betterbraces.com/aircast-sp-walking-brace

   Lavery, Pollo及Lawless^4-6等三個研究都指出，以商業製造的RCW而言，其在分散壓力pressure redistribution的能力和TCC相同，並且優於其他的減壓輔具。
   也因為可穿戴，而且總治療費用比TCC便宜，美國健保給付較優，故患者及醫師都比較喜歡使用RCW。但是臨床實證上TCC功效卻是遠大於RCW⁷，Armstrong認為原因在於使用RCW的患者會把鞋子脫掉，並且常常故意忘記穿上⁸，因此美國健保局(medicare)已明令規定，RCW只能用在骨科手術後限制腳踝關節用，若用在以減壓為目的，尤其是足底有傷口的狀況，美國健保局因沒有臨床效益而不予給付⁹。儘管最近已有新的關於RCW的研究。Katz等人發現¹⁰，若強迫使用RCW的患者禁止將RCW脫掉，則其傷口癒合效果會和TCC一樣。Katz的研究也呼應了Armstrong的這個假說。但是2010年有另一篇Faglia的研究指出¹¹，當使用某種特製的RCW，儘管其可脫脫穿穿，但其傷口癒合的功效和TCC相同。作者認為也許因為其穿脫更方便，讓患者願意下床時隨時穿著。

“Stabil-D” device and the “Modus” insole¹¹
1. Wu SC, Jensen JL, Weber AK, Robinson DE, Armstrong DG. Use of pressure offloading devices in diabetic foot ulcers : do we practice what we preach? Diabetes Care. 2008;31:2118-9.
2. Fleischli JG, Lavery LA, Vela SA, Ashry H, Lavery DC. 1997 William J Stickel Bronze Award. Comparison of strategies for reducing pressure at the site of neuropathic ulcers . J Am Podiatr Med Assoc 1997;87:466-72.
3. Piaggesi, A., Macchiarini, S., Rizzo, L., Palumbo, F., Tedeschi, A., Nobili, L. A., Leporati, E., Scire, V., Teobaldi, I., & Del Prato, S. (2007). An off-the-shelf instant contact casting device for the management of diabetic foot ulcers. Diabetes Care, 30(3), 586- 590.
4. Lavery LA,Vela SA, LaveryDC,Quebedeaux TL. Reducing dynamic foot pressures in high-risk diabetic subjects with foot ulcerations: a comparison of treatments. Diabetes Care 1996;19(8):818-21.
5. Pollo FE, Brodsky JW, Crenshaw SJ, Kirksey C. Plantar pressures in fiberglass totalcontact casts vs. a new diabetic walking boot. Foot Ankle Int 2003;24:45-9.
6. Lawless MW, Reveal GT, Laughlin RT. Foot pressures during gait: a comparison of techniques for reducing pressure points. Foot Ankle Int 2001;22:594-7.
7. Armstrong, D. G., Hienvu, C. N., Lavery, L. A., van Schie, H. M. C., Boulton, A. J. M., & Harkless, L. B. (2001). Off-loading the diabetic foot wound. Diabetes Care, 25(6), 1019-1022.
8. Armstrong, D.G., et al., Activity patterns of patients with diabetic foot ulceration: patients with active ulceration may not adhere to a standard pressure off-loading regimen. Diabetes Care, 2003. 26(9): p. 2595-7.
9. MOORE, JONATHAN, The Practice Management of Off-loading, Podiatry Management;Nov/Dec2012, Vol. 31 Issue 9, p119 http://www.podiatrym.com/pdf/2013/6/Moore1112web.pdf
10. Katz, I. A., Harlan, A., Miranda-Palma, B., Prieto-Sanchez, L., Armstrong, D. G., Bowker, J. H., Mizel, M.S., & Boulton, A. (2005). A randomized trial of two irremovable off- loading devices in the management of plantar neuropathic diabetic foot ulcers. Diabetes Care, 28(3), 555-559.
11. Faglia E, Caravaggi C, Clerici G, Effectiveness of removable walker cast versus nonremovable fiberglass off-bearing cast in the healing of diabetic plantar foot ulcer: a randomized controlled trial. Diabetes Care. 2010 Jul;33(7):1419-23. doi: 10.2337/dc09-1708. Epub 2010 Mar 31.