Effect of cervical proprioceptive training in shoulder impingement syndrome: a randomised controlled trial

Introduction Shoulder impingement syndrome (SIS) is a prevalent musculoskeletal condition characterised by marked pain and disability which prolong or recur in some patients even after undergoing the current interventions. Cervical proprioceptive training (CPT) may improve SIS outcomes but lacks research. This study was conducted to study the effects of adding CPT to the conventional exercises on shoulder pain, disability, and proprioception in SIS patients. Methods This randomised controlled, parallel group study included 40 patients (32 female, 8 male) diagnosed with SIS (by an orthopaedist and confirmed with specialist tests by the researcher) aged 37 ± 9 years old and BMI < 32 kg/m2 who were randomly (simple, using the closed envelop method) allocated (1:1) into two groups: group A treated with CPT and conventional exercises (scapular and rotator cuff strengthening, and posterior capsule stretching), and group B treated with conventional exercises only. The treatment lasted one month (3 sessions weekly). Patients were excluded if they had one of the following: shoulder osteoarthritis/trauma/infection/surgery, intra-articular injection, or symptomatic cervical pathology. Outcome measures were: change in shoulder pain and disability (using the Shoulder Pain and Disability Index), and cervical (flexion, extension, and right and left rotation) and shoulder (internal and external rotation) proprioception (using a laser pointer and the Protractor smartphone app, respectively) from baseline to one month (end of treatment). Paired t-tests and ANCOVA (with pre-test scores as covariates) were used to compare within- and between-group differences, respectively. This study was conducted at the outpatient clinic of 23rd of July Chest Hospital in El-Marg, Qalyubia, Egypt and extended from January 2023 to May 2024. Results Forty patients (20 in each group) were analysed; group A (n = 20, 17 female, 3 male, 37.7 ± 8.5 years, 28.37 ± 4.95 kg/m2), group B (n = 20, 15 female, 5 male, 35.8 ± 8.96 years, 28.29 ± 4.78 kg/m2). There were no significant differences between groups in demographics (p > 0.05). There were significant improvements in shoulder pain (p-value, 95% CI; effect sizes were < 0.001, 16.2–23.1, and 3 for group A, < 0.001, 9–19, and 1.3 for group B) or disability (p-value, 95% CI; effect sizes were < 0.001, 20.4–29.8, and 1.7 for group A, < 0.001, 9.7–23.5, and 1.13 for group B) post-treatment in either group with no significant differences between them, while there were significant improvements in shoulder internal rotation proprioception in group A only [p-value = 0.03, 95% CI: −3 – (−0.1), effect size (partial eta squared) 0.12]. Conclusions Adding cervical proprioceptive training to the conventional exercises improves shoulder proprioception over conventional exercises alone, while both interventions improve pain and disability equally. This may be important in the subcategory of patients who have functional/mechanical instability, but it requires further investigation.