Effect of blood flow restriction cuffs on joint proprioception with the example of the wrist

Background
Occlusion training, also known as blood-flow restriction training (BFR), is an exercise method in which the arterial inflow is partially restricted and the venous outflow is fully restricted in working muscles during exercise. Training performed under occlusion conditions is as effective as weight training with heavy loads. Joint proprioception plays a crucial role in maintaining stability and coordination during movement and protects against injury-causing movements. There is still a lack of studies on the effects of occlusion on joint position sense (JPS).

Aims
This study aimed to evaluate the effect of occlusion training by application of inflating tourniquets on joint proprioception using the example of the wrist.

Material and methods
The study group consisted of 40 volunteers, randomly divided into two groups: BFR and Placebo. The joint position sense test was performed twice in both groups using the Biodex isokinetic dynamometer. Measurement 1 was taken without an occlusion cuff. During measurement 2, in the BFR Group, an occlusion cuff was placed and inflated on the arm of the tested limb. In the Placebo Group, the cuff was applied but not inflated. The test was performed bilaterally for two target positions: 45° dorsiflexion and 30° palmar flexion. The subjects had their eyes covered with a blindfold. The analyzed parameter was the difference between the targeted position and the achieved position (°).

Results
The results obtained in measurements 1 and 2 were compared in both groups using the t-student test for the dependent groups. In both groups, the results of measurements 1 and 2 obtained for the target position of 45° were comparable (p=0.094-0.863). For 30°, in the BRF Group, the angular error was greater in measurement 2 than in measurement 1 (p=0.005-0.035). In the Placebo Group, there was no difference between measurements 1 and 2 (p=0.086-0.379).

Conclusions
This pilot study showed that the occlusion training cuffs placed on the upper arm may negatively affect wrist proprioception.