Comparison of the effects of muscle energy technique and positional release of latent trigger points of the sternocleidomastoid muscle on changes in pain threshold and bioelectrical activity of the trapezius muscle

Background
Trigger points TPs are defined as severely irritated areas in skeletal muscles or muscle fascia. They are painful during palpation, and generally, their symptoms are located away from the initial problem. Positional release (PRT) and muscle energy (MET) techniques stand out in particular and are among the most commonly used techniques by practitioners to treat TPs.

Aims
Comparison of the effects of MET and PRT of latent TPs of the sternocleidomastoid muscle (SMM) on changes in pain threshold and the bioelectrical activity of its antagonist, the trapezius muscle (TRM).

Material and methods
The study involved 72 students divided into two equal groups. In group A, the PRT procedure of latent TPs of SMM was applied using the Jones method. Group B underwent MET treatment of the same muscle. Pain threshold was assessed with a Microfet2 handheld dynamometer. Bioelectrical activity with NORAXON's surface electromyography (sEMG). Statistical analysis of the data was performed using Statistica 13.

Results
A single PRT and MET treatment significantly increased the compressive pain threshold of TRM, with no significant differences between the two. The mean TRM tension value at rest decreased using both therapies showing statistically significant changes. Changes in TRM tension during physical activity showed statistically significant differences only after MET treatment.

Conclusions
The comparability of both MET and PRT techniques in increasing the compressive pain threshold and decreasing the resting TRM tension after SMM therapy was demonstrated.