Association between clinical biomechanical metrics of cervical spine function and pain or disability in people with neuromusculoskeletal neck pain: Protocol for a systematic review and planned meta-analysis.

INTRODUCTION/BACKGROUND: Neck pain is a burdensome condition associated with pain, disability, and economic cost. Neck pain has been associated with observable changes in neuromuscular function and biomechanics. Prior research shows impairments in kinematic control, including reduced mobility, velocity, and smoothness of cervical motion. However, the strength of association between these impairments and patient-reported pain and disability is unclear rendering development of novel and relevant rehabilitation strategies difficult. The aim of this systematic review is to synthesize existing evidence on the strength of association between clinical biomechanical metrics of neck function (ROM, strength, acceleration, accuracy, smoothness, etc.) and patient-reported neck pain and disability. METHODS/ANALYSIS: This protocol follows Cochrane guidelines and adheres to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols (PRISMA-P). MEDLINE, EMBASE, CINAHL, SPORTDiscus, Web of Science and Scopus will be searched, along with the gray literature, up to 20 November 2023, using terms and keywords derived from initial scoping searches. Observational studies, including cohorts and cross-sectional studies, that explore associations between clinical biomechanics of the neck and patient-reported outcomes of neck pain or disability will be included. Two reviewers will independently perform study selection, data extraction, and risk of bias assessment (National Institute of Health tool). Data will be synthesized using either a random effects meta-analytic approach or qualitatively using a modified Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach, dependent on the homogeneity of data available. DISCUSSION AND RELEVANCE: This review addresses a gap in the literature by systematically synthesizing findings on the relationship between neck function impairments and patient-reported outcomes. It will identify priorities for neck pain rehabilitation and gaps in current knowledge. DISSEMINATION: The results of this review will be disseminated through a peer-reviewed publication, conference presentation, and lay language summaries posted on an open-access website. TRIAL REGISTRATION: PROSPERO Registration number: CRD42023417317. https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023417317.

Altered muscle strength and flexibility among a subgroup of women with chronic nonspecific low back pain: Cross-sectional case-control study.

OBJECTIVE: To compare muscle strength and flexibility among a subgroup of women with extension-related chronic nonspecific low back pain (CNLBP) with healthy controls. METHODS: In this case-control study, 32 subjects with and without extension-related CNLBP were tested (n = 16 in each group). Gluteal, abdominal, paravertebral, and hamstring strength, along with hip flexor flexibility and hamstring flexibility were compared between groups. Data were analyzed using the Mann-Whitney test (p < .007). RESULTS: The CNLBP subgroup displayed significantly lower strength of all muscles analyzed (p < .007), with the exception of gluteus medius. The flexibility of the hip flexors and hamstrings were not significantly reduced among the women with CNLBP (p > .007). DISCUSSION: The present study showed that alterations in muscle strength, but not flexibility, partly consistent with those previously hypothesized but not objectively reported, were present among a subgroup of women with extension-related CNLBP. These results may have implications for the selection of therapeutic exercises among this subgroup of people with CNLBP.

High- Versus Low-Molecular-Weight Hyaluronic Acid for the Treatment of Rotator Cuff Tendinopathy: A Triple-Blind Randomized Comparative Trial.

BACKGROUND: Shoulder pain most commonly originates from the tendon structures of the rotator cuff. OBJECTIVE: We compared the clinical effects of high- versus low-molecular-weight (LMW) hyaluronic acid for the management of rotator cuff tendinopathy. METHODS: We carried out a parallel, triple-blind, randomized comparative trial at a teaching hospital. In total, 56 patients aged 16 to 70 years with rotator cuff tendinopathy were randomly allocated to 2 groups. We administered a single shoulder injection of either 1 mL of 1% high- (>2000 kDa) or 1 mL of 1% LMW hyaluronate (500-700 kDa) to the corresponding groups. The primary outcome was the intensity of shoulder pain. The secondary outcomes were range of motion and disability of the shoulder, and quality of life. We performed the measurements at baseline and at 1, 4, and 12 weeks postintervention. The pain measurements were repeated at the sixth month postintervention. RESULTS: Comparisons of baseline versus 3 months showed that both interventions were beneficial in the management of the tendinopathy (all P values <0.05). However, between-group analyses did not indicate any clinically significant difference between the 2 medications. The pain, induration (P = 0.007), and inflammation at the site of the injection were less prominent for LMW hyaluronate. CONCLUSION AND RELEVANCE: Both medications are effective for the treatment of tendinopathy. The benefits last at least for 3 months, and pain alleviation lasts partially for 6 months. The shoulder injection of LMW hyaluronate is more tolerable to the patient. Therefore, we recommend LMW hyaluronate as the first choice for the management of rotator cuff tendinopathy.