TheUseandBenefitsofFocusedShockwavesfortheDiagnosisofMyofascialPainSyndromebyExaminingMyofascialTriggerPointsinLowBackPain

Low back pain (LBP) affects a substantial portion of the population, with lifetime prevalence estimates between 30% and 80%. While many cases are classified as "non-specific" because no clear structural cause can be identified, myofascial pain syndrome (MPS) is increasingly recognized as a major contributor. Studies suggest that MPS affects between 67% and 100% of patients with chronic LBP. The central element in diagnosing MPS is the identification of myofascial trigger points (MTrPs)—hyperirritable points within tight bands of skeletal muscle that produce local and referred pain.

However, the standard diagnostic method, manual palpation, suffers from significant problems with subjectivity and poor reliability between different examiners. This has created a pressing need for more objective, reproducible diagnostic tools. Focused Extracorporeal Shockwave Therapy (F-ESWT) has traditionally been used as a treatment modality, but its ability to deliver a precise, standardized mechanical stimulus to deep tissue layers has sparked interest in its potential as a diagnostic instrument.

The researchers conducted a single-center observational study with 28 patients who had chronic non-specific low back pain lasting more than three months. Participants were first examined by experienced physicians using manual palpation to identify MTrPs in the lower trunk, gluteal region, and thigh. A total of 115 MTrPs were selected for further investigation. These trigger points were then stimulated using focused shockwave therapy (F-ESWT) with a Wolf PiezoWave2 device, which has a precise focal zone of approximately 10mm in diameter.

The device allowed targeted stimulation at depths of 1–5cm depending on the muscle location. During stimulation, patients were asked two key questions to assess the two main diagnostic criteria: "Did you feel any pain locally and/or in other areas?" (to assess pain referral) and "Is this sensation and/or pain familiar to you or is this pain part of your usual complaints?" (to assess pain recognition). The researchers recorded the percentage of positive responses for each muscle tested.

The study found remarkably high diagnostic accuracy for several key muscles involved in low back pain. The quadratus lumborum muscle showed a 96.15% rate of pain referral and 84.62% rate of pain recognition. The gluteus medius muscle achieved 95.65% referral and 86.96% recognition, while the gluteus minimus showed 92.86% referral and 85.71% recognition. Other muscles also showed consistent but somewhat lower rates: the erector spinae (85.71% referral, 71.43% recognition), iliopsoas (92.86% referral, 50% recognition), biceps femoris (83.33% referral, 33.33% recognition), piriformis (81.82% referral, 36.36% recognition), and adductors (64.29% referral, 28.57% recognition).

Only one patient out of 28 showed neither recognition nor referral of pain. The lower back and gluteal regions contained the highest concentration of MTrPs.

These findings suggest that F-ESWT could serve as a valuable complementary diagnostic tool for myofascial pain syndrome, particularly in cases of chronic low back pain where diagnosis has been challenging. The ability to precisely stimulate deep tissue structures like the quadratus lumborum and gluteal muscles—often implicated in pseudo-radicular pain patterns—could help differentiate myofascial pain from true radiculopathy, potentially preventing unnecessary surgeries. The high recognition rates for certain muscles support the validity of F-ESWT as a standardized, reproducible stimulus that avoids the subjectivity problems of manual palpation. For patients, this could mean more accurate identification of the true source of their pain, leading to more targeted and effective treatments.

For clinicians, the technique offers a non-invasive method to confirm MTrP involvement with objective, recordable data. However, the study was limited by its small size, single-center design, and the fact that initial MTrP localization still relied on manual palpation. Further research with larger populations and direct comparison to other diagnostic methods will be needed to fully establish F-ESWT in routine clinical practice.