Direct Effect of Local Cryotherapy on Muscle Stimulation, Pain and Strength in Male Office Workers with Lateral Epicondylitis, Non-Randomized Clinical Trial Study

Abstract

Background: Local cryotherapy (LC) is one of the physiotherapeutic methods used in the conservative treatment of lateral epicondylitis (LE). The aim of the study was to verify the direct effect of a single LC procedure on the clinical symptoms of lateral epicondylitis enthesopathy (pain, pain free grip, PFG) and its effect on the bioelectrical properties of the wrist extensor muscles at rest, on maximal contraction and isometric contraction during fatigue. Methods: The study group was 28 men (35.4 ± 6.13 years) with confirmed unilateral epicondylitis. The performed procedures included the assessment of pain (visual analogue scale, VAS), PFG and ARMS (root-mean-square amplitude) and mean frequencies (MNF) of the sEMG signal before (T0) and after (T1) LC on the side with enthesopathy (ECRE) and without enthesopathy (ECRN/E). Results: There was an increase in the ARMS values of the signals recorded during rest and MVC from the ECR muscles both with and without enthesopathy (p = 0.0001, p = 0.006), an increased PFG after LC only on the side with LE (p < 0.0001) and decreased pain (p < 0.0001). During isometric fatigue contraction, a higher ARMS on both the ECRE side (p < 0.0001) and the ECRN/E side (p < 0.0001) was observed after LC treatment, and a lower MNF was observed on both the ECRN/E side (p < 0.0001) and the ECRE side (p < 0.0001) after LC. Conclusions: LC reduces the pain and increases PFG and muscle excitation expressed by ARMS and seems to delay muscle fatigue.

Keywords: fatigue; lateral epicondylitis; local cryotherapy; musculoskeletal pain; surface electromyography.

Figure 1

The flow chart presenting the developed research process.

Figure 2

Assessment of the effect of local cryotherapy on the A_RMS values recorded during rest (a) and MVC (b) and on the PFG (c) and VAS values (d). Legend: ECR—extensor carpi radialis longus and brevis muscles, _LE—lateral epicondylitis, _N/LE—healthy side, A_RMS—root-mean-square amplitude, MVC—maximum voluntary contraction, PFG—pain-free grip, VAS—visual analogue scale.

Figure 3

Change in the A_RMS value recording during a 60 s fatigue isometric contraction. Legend: A_RMS—root-mean-square amplitude, ECR—extensor carpi radialis longus and brevis muscles, _E—enthesopathy, _N/E—healthy side.

Figure 4

Change in the NF value recording during a 60 s fatigue isometric contraction. Legend: ECR—extensor carpi radialis longus and brevis muscles, _LE—lateral enthesopathy, _N/LE—healthy side, MNF—mean frequency.