Summary
The impact of orthotics on coordination was studied, which might be of relevance when performing sports activities.
Abstract
Purpose
Braces are often used after anterior cruciate ligament reconstruction (ACL-R) for knee protection. However, the impact of external stabilization and proprioreception remains debatable and orthotics do not seem to show impact on kinesthetic awareness. The purpose of the study was to evaluate the impact of braces and orthoses on the performance of subjects. It was hypothesized that orthotics reduces patient’s performance when completing the back in action battery.
Material And Methods
A single-blinded controlled crossover study design was performed including 24 subjects without any history of knee injuries. All of them were tested by using the back in action battery. All tests were performed three times, without an orthotics, with a brace or with an orthosis. The back in action test battery consists of a stability test, two leg and one leg countermovement jumps, standardized hop parkour and a speed test. Orthotics such as a functional soft brace (Genumedi® E+motion, Medi, Bayreuth, Germany), and a hard brace (M.4s® comfort, Medi, Bayreuth, Germany) were used in the study.
Results
The mean age of the 24 participants was 24+2 years, height 175+ 0.1cm and the weight of 65+8.5kg. No difference in the one leg and two legs stability testing was seen between the three test conditions. The mean jump height without orthotics was 27.6+8.4cm, with a brace 25.9+7.0cm, and with an orthosis 25.9+6.4cm (n.s.). The parkour was completed on average in 7.8+1.06s with an orthotics, 7.72+1.6s with a brace, and 7.88+1.2s with an orthosis without between group difference (n.s.).
Discussion
The main finding of the study was that orthotics did not show an impact in performance using the back in action test battery. Thus, orthotics did not influence the performance of healthy subject. The test battery was used to assess motor skills. The feedforward control is based on the experience with an expected task. Feedforward strategies are predominantly used when motor learning for a certain task has finished and the person is familiar with the task. When success is influences by external factors feedback mechanism become important. One explanation might be that healthy subject have few benefits only due to the rather determined fixed and forward based neuromuscular motor program used for performing the task. The lack of experience for benefiting from feedback advantages may explain why additional external proprioreception through braces or orthosis shows no impact on neuromuscular control. Orthotics do not influence speed and power. However, in ACL deficient or ACL repaired patients it might be different. The feedforward and the feedback systems are likely to be negatively influenced. Neuromuscular impairment has been shown in patients early and late after ACLR. Therefore the next step will be to perform the study with patients prior and after ACL reconstruction.
REFERENCES:
Hildebrandt, C.; Muller, L.; Zisch, B.; Huber, R.; Fink, C.; Raschner, C. Functional assessments for decision-making regarding return to sports following ACL reconstruction. Part I: Development of a new test battery. Knee Surg. Sports Traumatol. Arthrosc. 2015, 23, 1273–1281
Herbst, E.; Hoser, C.; Hildebrandt, C.; Raschner, C.; Hepperger, C.; Pointner, H.; Fink, C. Functional assessments for decision- making regarding return to sports following ACL reconstruction. Part II: Clinical application of a new test battery. Knee Surg. Sports Traumatol. Arthrosc. 2015, 23, 1283–1291
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