Punsola-Izard Vicenç, Carnicero Nuria, Ozaes-Lara Elena, Mendieta-Zamora Judit, Romera-Orfila Gemma, Schultz Karen S, Llusà Manuel, Casado Aroa
Hand Therapy Barcelona Physical Therapy and Clinical Investigation Center, 08010 Barcelona, Spain.
Physiotherapy Department, Gimbernat School of Physical Therapy, 08174 Barcelona, Spain.
J Clin Med. 2023 Apr 13;12(8):2855. doi: 10.3390/jcm12082855.
Proximal interphalangeal joint flexion contracture is a frequent condition in hand therapy. Clinicians most frequently apply orthosis management for conservative treatment. Orthoses should apply forces for long periods of time following the total end range time (TERT) concept. These forces necessarily transmit through the skin; however, skin has physiological limitations determined by blood flow. Using three fresh frozen human cadavers, this study quantified and compared forces, skin contact surfaces and pressure of two finger orthoses, an elastic tension digital neoprene orthosis (ETDNO) and an LMB 501 orthosis. The study also investigated the effects of a new method of orthosis construction (serial ETDNO orthoses) that customizes forces to a specific finger position. We evaluated forces and contact surfaces for multiple ETDNO models tailored to the cadaver fingers in multiple PIP flexion positions. The results showed that the LMB 501 orthosis applied pressures beyond the recommended limits if applied for more than eight hours a day. This fact was the cause of time limited LMB orthosis application. This results also show that, at 30° of PIPJ flexion, straight ETDNOs created a mean pressure approaching the end of the recommended pressure limits. If the therapist modified the ETDNO design, the skin pressure decreased and reduced the risk of skin damage. With the results of this study, we concluded that for PIPJ flexion contracture, the upper limit of force application is 200 g (1.96 N). Forces beyond this amount would likely cause skin irritation and possibly skin injuries. This would cause a reduction in the daily TERT and limit outcomes.
近端指间关节屈曲挛缩是手部治疗中常见的病症。临床医生最常采用矫形器治疗进行保守治疗。矫形器应根据总终末范围时间（TERT）概念长时间施加力。这些力必然会通过皮肤传递；然而，皮肤具有由血流决定的生理限制。本研究使用三具新鲜冷冻的人体尸体，对两种手指矫形器，即弹性张力数字氯丁橡胶矫形器（ETDNO）和LMB 501矫形器的力、皮肤接触面积和压力进行了量化和比较。该研究还调查了一种新的矫形器制作方法（系列ETDNO矫形器）的效果，该方法可根据特定手指位置定制力。我们评估了针对尸体手指在多个近端指间关节（PIP）屈曲位置定制的多个ETDNO模型的力和接触面积。结果表明，如果每天使用超过8小时，LMB 501矫形器施加的压力会超过推荐限度。这一事实是LMB矫形器使用时间受限的原因。该结果还表明，在近端指间关节屈曲30°时，直型ETDNO产生的平均压力接近推荐压力限度的上限。如果治疗师修改ETDNO的设计，皮肤压力会降低，皮肤损伤风险也会降低。根据本研究结果，我们得出结论，对于近端指间关节屈曲挛缩，力的施加上限为200克（1.96牛）。超过此量的力可能会导致皮肤刺激，甚至可能造成皮肤损伤。这会导致每日总终末范围时间减少，并限制治疗效果。
