Damm Philipp, Schwachmeyer Verena, Dymke Joern, Bender Alwina, Bergmann Georg
Julius Wolff Institute, Charité-Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany.
Clin Biomech (Bristol). 2013 Jun;28(5):530-5. doi: 10.1016/j.clinbiomech.2012.12.003. Epub 2013 May 2.
Patients with osteoarthritis, joint implants or fractures use crutches in order to reduce lower limb loading. However, insufficient information exists on how much the loading is then in fact reduced. This situation was studied by using seven patients who had instrumented hip implants.
Part I: To investigate the effectiveness of forearm crutches, crutch and hip joint contact forces were measured in seven patients with instrumented hip prostheses. Additionally, the bending moments in the implant neck and torsion around its stem were determined. Reductions of peak loads during 3, 4, and 2-point gaits were compared with loads present when walking without crutches. Part II: This examines joint load reduction during a 4-point gait from one to 12 weeks post-operatively.
Part I: During a 3, 4, and 2-point gait, the joint force was 17, 12, and 13% lower than it was while walking without crutches. The corresponding reductions of the bending moment were 16, 11, and 12%, while the maximum torque decreased by 19, 21, and 10%. Part II: The reductions of contact forces in comparison with walking without crutches were highest during the first 4 weeks after surgery. One and 4 weeks post-operatively, the force maximum was 21 and 8% lower than it was after 3 months. When compared with the initial values of the 1st week, crutch forces decreased by 28% in the 4th week and by 38% in the 3rd month.
Average reductions of the joint load by more than 20% are achieved only during the first 4 post-operative weeks. Because fractures are in most cases relatively stable after 6 weeks, and bone ingrowth into implant interfaces is nearly finished after this time, a single crutch and a 2-point gait can be prescribed during the 5th and 6th post-operative week.
骨关节炎患者、关节植入物患者或骨折患者使用拐杖以减轻下肢负荷。然而，关于负荷实际减轻了多少的信息却不足。本研究通过对7名植入了仪器化髋关节假体的患者进行研究来探讨这种情况。
第一部分：为研究前臂拐杖的有效性，对7名植入仪器化髋关节假体的患者测量了拐杖与髋关节的接触力。此外，还测定了假体颈部的弯矩及其柄部的扭矩。将三点、四点和两点步态时的峰值负荷降低情况与不使用拐杖行走时的负荷进行比较。第二部分：本部分研究术后1至12周四点步态期间关节负荷的降低情况。
第一部分：在三点、四点和两点步态期间，关节力比不使用拐杖行走时分别降低了17%、12%和13%。弯矩相应降低了16%、11%和12%，而最大扭矩分别降低了19%、21%和10%。第二部分：与不使用拐杖行走相比，术后前4周接触力降低幅度最大。术后1周和4周时，最大力比3个月后分别低21%和8%。与第1周的初始值相比，第4周拐杖力降低了28%，第3个月降低了38%。
仅在术后前4周关节负荷平均降低超过20%。由于大多数骨折在6周后相对稳定，且此时骨长入植入物界面几乎完成，因此在术后第5周和第6周可采用单拐和两点步态。
