Effects of Injection Combined With Spencer Technique on Painful Frozen Shoulder

\### What is this study about? This study compared whether adding the \*\*Spencer muscle energy technique (MET)\*\* versus conventional rehabilitation, following identical ultrasound-guided intra-articular corticosteroid-hyaluronate injection, improves shoulder outcomes for patients with painful-phase frozen shoulder (adhesive capsulitis). \### Why does it matter? Frozen shoulder causes shoulder pain and marked loss of range of motion, greatly impairing daily function and quality of life. The painful "freezing" phase is dominated by inflammation and pain-driven muscle guarding. Intra-articular injection can deliver short-term pain relief but cannot mechanically stretch contracted joint capsules; it therefore works best as a platform for subsequent rehabilitation. Although the Spencer muscle energy technique is widely used clinically for frozen-shoulder rehabilitation, prior trials often combined it with variable injection protocols and lacked direct comparison against standard rehabilitation. It remained unclear whether any observed benefits came from the injection itself or from the manual therapy technique. This trial fixed the injection and pain neuroscience education for both groups, isolating the effect of the manual therapy approach. \### What did the researchers do? Patients with unilateral painful-phase primary frozen shoulder were randomised into two groups. All participants received one ultrasound-guided glenohumeral and subacromial bursa injection (corticosteroid, hyaluronate, ropivacaine and normal saline), plus standardised pain neuroscience education. * \*\*Spencer group (n=33):\*\* 8-week programme of Spencer muscle energy technique * \*\*Control group (n=31):\*\* 8-week conventional rehabilitation (joint mobilisation, manual therapy and stretching) * Outcomes were assessed at \*\*baseline, 8-weeks (end-of-treatment), and 24-week follow-up\*\* * Primary outcome: shoulder function measured by the Constant-Murley score * Secondary measures: pain (NRS), kinesiophobia (TSK-17), mental quality-of-life (SF-36 MCS), active shoulder range of motion, and ultrasound thickness of the coracohumeral ligament and inferior glenohumeral capsule * Outcome assessors and data analysts were blinded to group allocation; safety and adverse events were monitored throughout the trial.

Inclusion Criteria: * Aged 18-70 years * Willing to undergo randomization * Diagnosis of primary idiopathic frozen shoulder; diagnosis confirmed by the primary author, defined as limited active and passive shoulder range of motion, with characteristic restricted passive external rotation (\