Effect of different osteopathic techniques on the tone and electrical activity of the sternocleidomastoid muscles

Introduction. At an osteopathic doctor’s appointment, musculoskeletal neck pain is the most common reason for consultation, reaching 60 %. Osteopathic doctors use a wide range of manual techniques to diagnose and correct somatic musculoskeletal dysfunction, including articulation and muscle-energy techniques (MET). Both types of techniques can increase cervical spine mobility, decrease neck muscle tone, and alter the viscoelastic properties of soft tissue, including in asymptomatic individuals. No studies on the effect of MET and articulation techniques on neck muscle tone according to surface electromyography (SEMG) were found. Comparison of the effect of different osteopathic techniques on the bioelectrical activity of neck muscles in one group of subjects was also not conducted. The aim of the study : to compare the effect of muscle-energetic and articulation osteopathic techniques on the bioelectrical activity of neck muscles in young people with no complaints of neck pain. Materials and methods. From December 2023 to March 2024, a study was conducted at the Department of Osteopathy of I. I. Mechnikov NWSMU (Saint-Petersburg) with 30 participants aged 22 to 44 years (median 27 years), including 17 women and 13 men. At the time of examination, they actively did not present complaints of musculoskeletal pain. Inclusion criteria were the presence of diseases and/or conditions that were absolute contraindications to osteopathic correction, a history of neck trauma; the presence of metal structures in the spine; taking medications affecting muscle tone at the time of the study; and neuromuscular diseases. Each participant in the study was treated twice: in the first stage of MET on the neck and in the second stage at least one month of articulation on the neck. Before and immediately after osteopathic treatment, the tone of the sternocleidomastoid muscles (SCMM) was palpatory examined and the average amplitude of their electrical activity A av. (pV) at rest was recorded using SEMG, which was performed on the Kolibri wireless electrophysiologic signal monitoring complex («Neurotech», Russia). Recordings were made synchronously from the right and left sides of the body, then the asymmetry of electrical activity was calculated as the modulus of the difference A av. between the left and right sides. Results. During palpatory examination before the exposure at both stages, the tone of the SCMM was most often evaluated as normal or elevated. After application of both MET and articulation, the number of persons with hypertonus statistically significantly decreased and increased with normotonus ( p =0,02), while the groups before and after application of these techniques did not differ from each other ( p >0,05). The average amplitude of the electrical activity of the SCMM after both MET and articulations was statistically significantly decreased, indicating a decrease in muscle tone. There was no statistically significant difference in this index before and after osteopathic techniques at the first and second stages ( p >0,05). After MET, there was a tendency to decrease the asymmetry of the average electrical activity between the left and right SCMM, but these changes were not statistically significant ( p =0,11). After articulation, the asymmetry of average electrical activity between the left and right SCMM decreased statistically significantly ( p =0,032). Conclusion. A single application of osteopathic techniques of MET and articulation equally reduces muscle tone and, accordingly, the electrical activity of the sternocleidomastoid muscles. At the same time, articulations additionally reduce the asymmetry of electrical activity of these muscles, i. e. they normalize muscle tone more harmoniously. To objectify for the doctor and the patient such an important result of osteopathic correction as a decrease in muscle tone and reduction of its asymmetry, the method of surface EMG is recommended. If the method of electrode application and examination is followed, this method gives reliable and repeatable results, which is the basis for its use as an objective method of proving the effectiveness of osteopathic techniques.