Myofascial syndrome is a pathology of the musculoskeletal system manifested by referred dull pain associated with functional limitation, contractures, and with possible neuralgic-type manifestations. This condition is characterized by the presence of “trigger points” (TPs) defined as circumscribed focuses of hyper-irritability; the pain caused by acupressure of “TPs” is a “referred” pain, in that it is felt in specific areas (target area), not necessarily adjacent to the stimulated point (1). There are two types of “TPs”: active ones, which are associated with pain even in the absence of movement or palpation; and latent ones, which are painful only upon acupressure; TPs cause muscle weakness and limitation of joint range of motion (2). The pathogenesis of myofascial pain syndrome is still questionable. The most widely accepted hypothesis in the scientific literature attributes the onset of myofascial trigger points (MTrPs) to prolonged contraction of the sarcomere, caused by increased release of acetylcholine at the neuromuscular junction. Pain, therefore, is generated at MTrPs as a result of compression of blood vessels located within the contracted muscle tissue: an ischemic process ensues in situ with release of algogenic substances and stimulation of muscle nociceptors (3). In the presence of a constantly altered mechano-metabolic environment, changes occur in the connective tissue constituting the myofascial system, and nociceptive sensation increases: fibroblasts in fact transform into myofibroblasts, contributing to the shortening of the surrounding tissue and increased tone; receptors present within the fascia may transform into nociceptors and become sensitive to mechanical stimuli (allodynia or mechanical hyperalgesia). Therefore, as the structure of connective tissue changes, the polarization of muscle fibers can be altered, thus leading to spontaneous muscle contraction. In addition, at the level of the extracellular matrix, the properties of hyaluronic acid are altered, resulting in increased viscosity and difficulty in the sliding of muscle layers with more difficult muscle contraction (4); nerve endings in the fascia in the more viscous area are stretched, activating constantly and thus generating trigger points. Alterations in blood flow can also cause myofascial pain: the change in flow velocity induces an alteration in the morphology and function of muscle capillaries, causing ischemia during small active movements; this activates type IV nerve endings, contributing to myofascial pain (5). Myofascial syndrome in addition to pain is associated with functional limitation with reduced autonomy in ADLs, leading to alterations in quality of life (6). The diagnosis of myofascial syndrome is made following clinical evaluation by identification of myofascial trigger points: these are sought by palpation of the patient’s painful areas and are defined by the presence of a palpable taut band within the superficial or deep muscle tissue. The muscles involved are usually not uniform, but have heterogeneous areas of different consistencies (7). Myofascial pain syndrome can involve all the muscles of our body, but the muscles of the cervical district (particularly the trapezius muscles, the sternocleidomastoid muscle, the shoulder elevator muscle) are most involved (8, 9), the muscles of the lumbar spine (quadratus lumborum muscle and paravertebral muscles) (10, 11) and the muscles of the lower limbs (tensor fasciae latae muscles, hip adductors, biceps femoris, quadriceps, gastrocnemius and popliteus muscles) (12). Myofascial pain syndrome is often associated with other pathologic conditions of the musculoskeletal system of a chronic degenerative nature that occur in old age such as osteoarthritis (13).

The treatment of myofascial syndrome is varied and heterogeneous; pharmacological therapy with muscle relaxants, antidepressants, weak opioids, local anesthetics, and anti-inflammatories taken orally or topically (in the form of a patch or by mesotherapy) is often used for the management of algic symptoms and painful “PTs” (14, 15). Rehabilitative treatment with active and constant exercise is an effective strategy in the treatment of myofascial pain: it improves joint ROM, mood, and pain threshold, promoting a better quality of life for patients; one of the prescribed exercises is stretching, which stretches myofascial compartments containing PTs and prevents their further occurrence; postural rehabilitation is another rehabilitation option (16). Patients also often undergo massage therapy and manual therapy sessions. Two widely used techniques for the treatment of the aforementioned condition are dry needling and ischemic compressions resulting in increased muscle metabolism (17, 18). Among the most widely used physical therapies in myofascial syndrome are focal ultrasound and shockwaves, which by applying mechanical and thermal energy to the underlying connective tissue, improve circulation, elasticity, and metabolism (19, 20); High Iintensity Laser Therapy (HILT) and Tecartherapy also act on local inflammation, promoting repair of damaged muscle tissue and reducing algic symptoms (21).

Focal shockwaves are acoustic waves (sound pulses, mechanical in nature), characterized by a particular wave shape (first phase of positive pressure, followed by a subsequent rapid, less extensive phase of negative pressure), high energy and short duration, which act on a specific, well-defined point, and therefore are widely used in the treatment of numerous musculoskeletal disorders. They have a beneficial pain-relieving and anti- inflammatory effect (22–24). Analgesic mesotherapy is an outpatient treatment involving multiple mesodermal microinjections of active substances, administered through 27G 0.4 × 4 mm needles, at body parts affected by pain and functional limitation. This technique allows a small amount of drug to be used directly on the area to be treated, reducing systemic drug intake (25, 26).

The aim of the study is to compare treatment with focal Extracorporeal ShockWave Treatment (ESWT) and antalgic mesotherapy in patients with myofascial pain syndrome in terms of pain reduction, increased functional capacity, and autonomy in Activities of Daily Living (ADLs) with improved quality of life.

From daily outpatient evaluations performed from April 2023 to October 2023 at our Functional Recovery and Rehabilitation Unit, we enrolled 69 patients with myofascial pain syndrome. Of these, 6 patients did not fit the inclusion criteria and another 9 had exclusion criteria instead, so only 54 patients were included in the study. The sample size was 51 with a 99% confidence level and a margin of error of 5%. The participants were randomly divided into two groups of equal number and underwent ESTW therapy (Group A) and mesotherapy treatment (Group B).

The demographic characteristics of the sample and initial assessment are summarized in Table 1, which shows the homogeneity of the two groups. The included patients had a mean age of 48.76 ± 9.54 years and included 24 men (44.4 percent) and 30 women (55.6 percent). The sites involved were cervical spine (63%), lumbar spine (18%t), and shoulder muscles (19%). The patients at recruitment had a mean NRS value of 7.03 ± 0.88, a mean PPT Scale of 2.18 ± 0.73. Finally, they had an SF-36 value of 82.5 ± 7.91. No statistically significant between- group differences in baseline characteristics were reported. No statistically significant between-group difference in baseline characteristics was reported (Table 1).

Table 2 shows the results obtained in group A (ESWT) at T1 and T2. Statistically significant results were found at T1 for all variables considered, with a modest improvement in the values of NRS (4.11 ± 1.12; ≤ 0.05) and PPT Scale (1.18 ± 0.39; ≤ 0.05), as well as SF-36 (93.59 ± 4.54, ≤ 0.05). These results were maintained at T2, but no statistically significant values emerged in terms of pain reduction and improvement in quality of life and autonomy in ADLs (Table 2).

Table 3 shows the effects of mesotherapy in group B, at the end of treatment (T1) and 30 days after the end of therapy (T2). In this group, too, there were statistically significant improvements for all research domains at T1: NRS (5.29 ± 1.17; ≤ 0.05), PPT Scale (1.44 ± 0.5; ≤ 0.05) and SF-36 (90.4 ± 5.19; ≤ 0.05); however, again at follow-up 30 days after the end of therapy (T2), no statistically significant values emerged, as shown in the table (Table 3).

Finally, we compared the results obtained in Group A and Group B at T1. The comparative analysis of the results obtained in the two groups showed substantial differences: in fact, the comparison of the results obtained in the two groups at T1 shows that the patients treated with ESWT (Group A) obtained better results, compared to the patients treated with mesotherapy (Group B) with statistical significance, in terms of pain reduction, assessed by the NRS scale (4.1 ± 1.1 vs. 5.3 ± 1.2; ≤ 0. 05) and the PPT scale (1.2 ± 0.4 vs. 1.4 ± 0.5; ≤ 0.05), and improvement in quality of life, by scores obtained with the SF-36 (93.6 ± 4.5 vs. 90.4 ± 5.2; ≤ 0.05) (Table 4).

Myofascial syndrome is a musculoskeletal disorder that is characterized by the presence of “trigger points” (1). In this study, we compared the effects and benefits of two different therapeutic approaches in the management of MPS in terms of improving functional capacity. We also compared the effects of these methods on pain reduction, pain pressure perception, and quality of life. Our results showed that focal ESWT and mesotherapy are two valuable therapeutic proposals in the management of patients with myofascial pain syndrome. In fact, the treatment of myofascial syndrome is multimodal; we make use of pharmacological therapy (anti- inflammatories, muscle relaxants, local anesthetics, antidepressants and weak opioids), (14, 15) often in association with rehabilitative treatment with active and constant exercise, stretching exercises and postural rehabilitation (16).

The synergism of pharmacological therapy and rehabilitative treatment, in association with physical therapies (ESWT-TECARtherapy-HILT) seems to be the best treatment strategy to date (19–20–21). The scientific literature unevenly addresses treatment for myofascial syndrome; in fact, different authors have implemented different treatment options. Ahi et al. (33) compared the effectiveness of high-intensity laser therapy (HILT) and “dry needling” in patients with myofascial pain syndrome and showed that these therapeutic alternatives in addition to exercises contribute to pain reduction. Appasamy et al. (34), on the other hand, conducted a study evaluating the various injection therapies at the level of trigger points in patients with MPS; they compared both the dry needling technique and the various pharmacological administrations of local anesthetics or corticosteroids and concluded that through a detailed history and a proper objective examination, a proper treatment strategy can be developed, appropriate to each patient’s clinical condition.

Several studies have evaluated the effectiveness of dry needling in myofascial pain syndrome, defining its importance in addition to rehabilitative exercises (35), and evaluating verbal suggestion on pain perception during therapy sessions (36, 37). Other popular treatments include manual therapy and dry cupping. Numerous studies have compared the effectiveness of each treatment in short-term relief of myofascial pain (38–42). An additional therapeutic alternative is acupuncture; in the scientific literature many authors have highlighted the effectiveness of this treatment in patients with myofascial pain syndrome (43, 44). Several studies have been performed comparing ESWT with other treatment options: Paoletta et al. (45) performed a review on PubMed to analyze the efficacy of ESWT in patients with myofascial syndrome and found a beneficial role of ESWT in improving clinical and functional outcomes; Yalçın et al. (46) compared the efficacy of kinesiotaping (KT) and ESWT on pain threshold and particularly on coordinated movements by neck muscles and concluded that the combination of exercise, KT and ESWT in MPS was effective in all parameters examined. Nahomi Kuroda et al. (47) also conducted a study comparing “ischemic compressions” (IC) with ESWT demonstrating the effectiveness of ESWT in reducing symptoms. Jun et al. on the other hand, wanted to evaluate the effectiveness of ESWT therapy in myofascial pain syndrome involving neck and shoulder muscles; they stated that ESWT therapy is superior to other treatments in terms of alleviating pain intensity and pressor pain threshold (48). Finally, Hong et al. (49) analyzed different treatments on trigger points at the level of the muscles of the lumbar spine; comparing the treatments, they showed that ESWT was more effective than TPI in relieving pain. In light of the above and with regard to our results, we can state that a study comparing ESWT and antalgic mesotherapy has never been conducted; other strengths of this study are adequate number of samples in both arms and multiple rating scales along with different statistical methods used. The main limitation of our study is the small sample size, therefore, further research should focus on a larger number of patients.

In patients with myofascial pain syndrome, the use of focal ESWTs can be considered a safe and effective treatment in reducing algic symptoms and improving short- and long-term quality of life. Mesotherapy has also been shown to be an effective alternative in the management of pain in MPS patients; however, ESWT, despite being mildly painful but tolerated, has been shown to be superior to mesotherapy in terms of pain reduction and increased functional capacity, and has not exposed patients to drug intake, albeit by the mesodermal route. It would be desirable in the not-so-distant future to compare the different efficacy of the two treatments for the two different groups on a larger sample of patients.

The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.

DS: Conceptualization, Data curation, Investigation, Software, Validation, Visualization, Writing – review & editing. DM: Conceptualization, Formal analysis, Investigation, Methodology, Resources, Software, Writing – original draft. LL: Data curation, Validation, Writing – review & editing. FQ: Formal analysis, Investigation, Writing – original draft. NC: Formal analysis, Investigation, Writing – review & editing. ST: Formal analysis, Writing – review & editing. MV: Writing – review & editing. GM: Supervision, Writing – review & editing.