Rishiraj Neetu, Taunton Jack E, Lloyd-Smith Robert, Regan William, Niven Brian, Woollard Robert
ACTIN Health and Rehabilitation Inc., 5767 Oak Street, Vancouver, BC, V6M 2V7, Canada.
Knee Surg Sports Traumatol Arthrosc. 2012 Dec;20(12):2405-12. doi: 10.1007/s00167-012-1911-z.
The aim of the study was to investigate the landing strategies used by non-injured athletes while wearing functional knee braces (FKB, BR condition) during a drop jump task compared with non-injured, non-braced (NBR condition) subjects and also to ascertain whether accommodation to a FKB was possible by non-injured BR subjects.
Twenty-three healthy male provincial and national basketball and field hockey athletes (age, 19.4 ± 3.0 years) were tested. Each subject was provided with a custom-fitted FKB. Five NBR testing sessions were performed over 3 days followed by five BR testing sessions also over 3 days, for a total of 17.5 h of testing per condition. Each subject performed eight trials of the drop jump task during each testing session per condition. Single-leg peak vertical ground reaction forces (PVGRF) and the time to PVGRF were recorded for each NBR and BR trail.
The BR group mean PVGRF at landing was significantly lower (1,628 ± 405 N, 2.1 ± 0.5 BW versus 1,715 ± 403 N, 2.2 ± 0.5 BW, F (1,22) = 6.83, P = 0.01) compared with NBR subjects, respectively. The group mean time to PVGRF was not statistically longer during the BR condition (F (1,22) = 0.967, P = 0.3). Further, an accommodation trend was noted as percent performance difference decreased with continued FKB use.
The significantly lower group mean PVGRF while using a FKB could keep traumatic forces from reaching the ACL until the active neuromuscular restraints are activated to provide protection to the knee joint ligaments. Also, accommodation to FKB is possible after approximately 14.0 h of brace use. The results of this paper will assist clinicians in providing information to their patients regarding a FKB ability to offer protection to an ACL-deficient knee or to address concerns about early muscle fatigue, energy expenditure, heart rate, and decrease in performance level.
Prospective study, Level I.
本研究旨在调查未受伤运动员在进行下蹲跳任务时佩戴功能性膝关节支具（FKB，即支具佩戴状态）与未受伤且未佩戴支具（NBR状态）的受试者相比所采用的落地策略，同时确定未受伤的支具佩戴受试者是否能够适应FKB。
对23名健康的省级和国家级篮球及曲棍球男运动员（年龄19.4±3.0岁）进行测试。为每位受试者提供一副定制的FKB。在3天内进行5次NBR测试，随后同样在3天内进行5次BR测试，每种状态总共测试17.5小时。每位受试者在每种状态的每次测试中进行8次下蹲跳任务试验。记录每次NBR和BR试验的单腿垂直地面峰值反作用力（PVGRF）以及达到PVGRF的时间。
与NBR受试者相比，BR组落地时的平均PVGRF显著更低（分别为1628±405N，2.1±0.5体重与1715±403N，2.2±0.5体重，F(1,22)=6.83，P=0.01）。BR状态下组平均达到PVGRF的时间在统计学上没有显著延长（F(1,22)=0.967，P=0.3）。此外，随着持续使用FKB，性能差异百分比降低，出现了适应趋势。
使用FKB时显著更低的组平均PVGRF可使创伤力在主动神经肌肉约束被激活以保护膝关节韧带之前不会作用于前交叉韧带。此外，在使用支具约14.0小时后有可能适应FKB。本文结果将帮助临床医生向患者提供关于FKB对ACL损伤膝关节提供保护的能力的信息，或解决对早期肌肉疲劳、能量消耗、心率和性能水平下降的担忧。
前瞻性研究，I级。
