以足底壓力參數分析急性下背痛患者之步態特徵

Analysis of the Gait Characteristics of Subjects with Acute Low Back Pain by Foot Pressure Parameters

本研究收集急性下背痛患者24例（男11例，女13例）及正常對照組48例（男25例，女23例）。評估視覺疼痛指數（pain visual analogue scale）、疼痛區域（pain drawing），並使用Footscan平板式足壓量測系統（RSscan Inc., Belgium）及6.3.4.3軟體測量足底壓力，分析接觸時間（contact time）、接觸時間百分比（contact%）、足底最大壓力（Pmax）及壓力—時間積分。以independent t test改成中文檢定參數間的差異。發現急性下背痛患者雙足接觸時間比正常人長（p＜0.05），特別是大拇趾（T1）及足跟（H）的區域（p＜0.05），且右外足跟及前足第一蹠骨接地起始時間較晚，右外足跟接地期較長（p＜0.05）。前足內側及足跟內側的標準化最大壓力比正常人低（p＜0.05），且壓力—時間積分值在右大拇趾區的值比正常人低。本研究顯示急性下背痛患者步行時，藉由增加足部與地面接觸時間、延遲足跟著地及減緩推進（push-off）的動作，以減少地面衝力及地面反作用力，並進而減少背部肌肉收縮，以減輕疼痛。

Our study enrolled 24 patients (11 men, 13 female) with acute low back pain and 48 healthy subjects (25 male, 23 females). Visual analogue scale (VAS) for pain, pain drawing and foot pressure were evaluated. Foot pressure was measured by Footscan (RSscan Inc., Belgium) with 6.3.4.3. Software. Foot pressure measured variables including contact time, percentage of contact time, maximal plantar pressure (Pmax) and Pressure-time integral were collected. Independent t test was used to analyze the data. The results revealed that the contact time in persons with acute low back pain was longer than that of the control subjects (p＜0.05), especially in big toe (T1) and heel (H) (p＜0.05). Right heel and forefoot were delayed at time of initial contact on the ground in persons with acute low back pain (p＜0.05). Compared with control group, persons with acute low back pain had lower standardized Pmax in medial forefoot and heel (p＜0.05). The lower impulse value over right big toe area was lower than that of the control groups. Our conclusion is that subjects with acute low back pain present an asymmetric gait pattern with longer contact time as well as delayed heel strike and push-off in order to reduce the impact force from the ground, which subsequently reduce back muscle contraction and low back pain.