Immediate effect of extracorporeal shockwave therapy in patients with chronic non-specific low back pain: A randomised placebo-controlled triple-blind trial.

OBJECTIVE: To compare the immediate effects of shockwave therapy using two different tips in patients with chronic non-specific low back pain. DESIGN: Randomised placebo-controlled study with three intervention groups. SETTING: The patients recruited for this study were sent for physiotherapy treatment at primary care between May and July 2022. PARTICIPANTS: Eighty-one patients with chronic non-specific low back pain aged 18-80 years with pain for ≥3 months and pain intensity ≥3 were randomly recruited for the study. INTERVENTION: The patients received a single intervention of radial shockwave therapy with 2000 discharges at 100 mJ energy and 5 Hz frequency using concave or convex tips or placebo treatment. MAIN MEASURES: The primary outcome was pain intensity immediately post-intervention. The secondary outcomes were pressure pain threshold, temporal summation of pain, and functional performance. Data were collected at baseline and post-intervention. RESULTS: The post-intervention pain intensity in the concave tip group is an average of two points lower (95% CI = -3.6, -0.4; p < 0.01) than that in the placebo group. The post-intervention pressure pain threshold for the concave tip group was an average of 62.8 kPa higher (95% CI = 0.4, 125.1; p < 0.05) than for the convex tip group and 76.4 kPa higher (95% CI = 14, 138.7; p < 0.01) than in the placebo group. CONCLUSION: The concave tip shockwave therapy is effective in reducing pain and local hyperalgesia in patients with chronic non-specific low back pain.

Photobiomodulation therapy and transcutaneous electrical nerve stimulation on chronic neck pain patients: Study protocol clinical trial (SPIRIT Compliant).

INTRODUCTION: Chronic neck pain is a common musculoskeletal disorder that is associated with functional disability and decreased of quality of life. Electrophysical agents are commonly used to relieve pain, however the effects of combined use of these agents are little studied. The objective is to investigate the efficacy of photobiomodulation and electrical stimulation to relieve pain, both in isolation and combined. MATERIALS AND METHODS: This a 4-arm randomized placebo-controlled trial with patient and evaluator blinded. This study will be performed in Department of Physical Therapy at Federal University of São Carlos, São Carlos/SP, Brazil. One hundred and forty-four patients with chronic neck pain will be randomized into 4 groups: active photobiomodulation therapy with active electrical stimulation, active photobiomodulation therapy, active electrical stimulation, or placebo treatment. They will receive 10 sessions of treatment. PRIMARY OUTCOME: pain intensity (measured by pain numerical rating scale) posttreatment. SECONDARY OUTCOMES: pain during movement, neck disability, range of motion, pressure pain threshold, temporal summation, conditioned pain modulation, depressive symptoms, pain catastrophizing, quality of life, analgesic intake, and global perceived effect at posttreatment (10 sessions). Pain intensity and global perceived effect will also be measured after 6 weeks randomization. DISCUSSION: The findings of this study might clarify the importance of using the photobiomodulation therapy and transcutaneous electrical nerve stimulation for patients with chronic neck pain. TRIAL REGISTRATION: NCT04020861. https://clinicaltrials.gov/ct2/show/NCT04020861?term=NCT04020861&draw=2&rank=1.

Change in the contractile behavior of muscle fibers in subjects with primary muscle dysfunction.

The mechanical and metabolic characteristics of skeletal muscle fibers can interfere with muscle contractile performance in healthy subjects. Few studies have investigated the degree of association between muscle function and muscle fiber morphology in patients with myopathy. A biopsy was obtained from the left biceps brachii muscle of 12 subjects with myopathic disorders. The relative cross-sectional area of type 2 fibers and their subtypes was determined by the ATPase technique. Relative torque (RT) was calculated by dividing isokinetic elbow flexion peak torque (PT) values (90 and 180° s-1) by isometric PT values. Correlations were analyzed using Spearman's coefficient (r). The relative cross-sectional area of type 2b fibers was positively correlated with RT90 (r = 0.71, P = 0.009) and RT180 (r = 0.73, P = 0.007). The relative cross-sectional area of type 2a fibers showed a moderate and negative correlation with RT180 (r = -0.62, P = 0.03) and a low correlation with RT90 (r = -0.57, P = 0.05). In contrast to healthy subjects, patients with myopathy presented changes in the contractile behavior of type 2a fibers and compensatory adaptations in type 2b fibers. The results suggest that RT in combination with morphometric parameters provides data regarding muscle function in patients with myopathic disorders and can contribute to the establishment of therapeutic exercises.