Diagnostic labels for shoulder pain are frequently used, yet no standardised diagnostic criteria for any of the labels have been described. One such diagnostic label, subacromial shoulder impingement (SSI), is commonly used as an umbrella term for all subacromial pain with no indication of aetiology or mechanism of pain production. Indeed, the aetiology and specific mechanism of SSI remain robustly debated.
Physiotherapy is a common conservative treatment intervention in SSI. Current level II evidence (randomised controlled trials [RCTs]) for the effectiveness of physiotherapy in those with SSI has not provided information about targeted interventions linked to specific biomechanical factors. No clear judgements can be deduced from these RCT's due to limitations of heterogeneity in inclusion criteria, limitations in standardisation of interventions, the lack of matching of upper-limb dominance and not including objective outcomes within methodology. A major focus of physiotherapy is the identification of muscular, neuromuscular and joint impairments, with identified impairments targeted in the treatment programme. While several purported biomechanical factors have been suggested for extrinsic SSI, they have not been clearly described, and this has led to current use of nonspecific treatment interventions to embrace all possible impairments.
An initial literature review within this research programme identified four biomechanical factors purported to be associated with extrinsic SSI: posterior shoulder tightness, thoracic postural impairment, scapula impairment and rotator cuff impairment. Reliable and valid objective physiotherapy clinical tests for each of these four biomechanical factors were then identified, using a systematic literature review, prior to conducting a rigorous original casecontrol study to establish which, if any, were different between a group experiencing SSI symptoms and an asymptomatic group, matched for age, gender, limb dominance and physical activity level.
Crude analyses revealed that the SSI group had significantly increased resting thoracic flexion and forward head posture, as well as a significant reduction in upper thoracic active motion, posterior shoulder range and passive internal rotation range. It is not known if these identified differences were contributing to or a result of SSI.
An RCT was conducted to determine if interventions focused on the upper thoracic spine and posterior shoulder were effective in the management of SSI. This original RCT, which followed the CONSORT statement and was a registered trial with the Australian New Zealand Clinical Trials Registry (12615001303538)1, identified mobilisation of the upper thoracic spine or massage and mobilisation of posterior shoulder structures combined with a targeted single home exercise, in a homogeneous group with SSI, significantly improved function and passive internal rotation range, suggesting that manual therapy that addresses these extrinsic contributing factors decreases the signs and symptoms of SSI.
The outcomes of this research provide physiotherapists with a focused assessment and treatment pathway of the thoracic spine and posterior shoulder in those aged 40–60 years presenting with signs and symptoms of extrinsic SSI. This study is the first step in developing a physiotherapy clinical pathway for shoulder pain, which can be presented to health insurers and other health providers. Further rigorous research is required for a complete pathway for other causes of shoulder pain
