Background
As a group, musculoskeletal conditions are associated with the second highest number of ‘years lived with disability’.1 Within this group, conditions affecting the shoulder occur frequently in sporting and non-sporting populations,2–4 and their prevalence increases with age.5 Annually, 1–2% of the general population present to their general practitioner (family physician) with a first episode of shoulder pain,6–8 and of concern, these conditions are associated with high levels of morbidity lasting for 1 year or longer.3 ,8
To understand the basis of the presenting shoulder symptoms, clinicians typically perform a clinical examination, which usually includes: taking a history, collecting disability and impairment data and performing special orthopaedic tests that have been designed to incriminate pathology, such as that involving the rotator cuff tendons, subacromial bursa or glenoid labrum, or to rule in conditions, such as subacromial impingement syndrome.9
Although orthopaedic tests are commonly used,9 findings from narrative10–13 and systematic reviews14 ,15 and research investigations16 have consistently questioned the value of these procedures as a method of implicating the structures associated with the presenting symptoms. Imaging is commonly used to support the clinical assessment.17 Likewise, the certainty with which imaging findings support or confirm the clinical diagnosis is challenged by myriad studies reporting asymptomatic structural deficits, including full-thickness rotator cuff tears and glenoid labral tears, in populations including elite athletes.18–21 One implication of current clinical practice is that people with shoulder pain may undergo operations to repair tissues that are not related to their presenting symptoms.13
The findings of these clinical and radiological investigations have challenged the basis on which a structural diagnosis may be achieved.10 ,13 ,22 This has been recognised previously and researchers have suggested that assessment and management could be based on the presenting symptoms without the need for a definite structural diagnosis.23 ,24 One such model, known as the Shoulder Symptom Modification Procedure (SSMP), was first described by Lewis10 as a systematic approach to assess clinical variables that may be associated with shoulder symptoms, to determine their relationship with the presenting symptoms. Similar to the Mulligan and McKenzie et al approaches,23 ,24 procedures identified that partially or completely improve the presenting symptoms may be considered in patient management. By placing the individual patient at the centre of the assessment and management decision process, these methods are compatible with patient-centred practice, clinical reasoning and evidence-based practice.22 ,25 ,26
Shoulder Symptom Modification Procedure
The first stage of the SSMP is for the patient to identify the movements, activities or postures that reproduce symptoms. This may include symptoms experienced while sitting at a desk, lifting a pan or kettle, dressing, swimming, performing weight-bearing activities such as push-ups and in high-powered explosive activities commonplace in sport. Pain is the most commonly reported symptom, but symptoms may also include reduction in movement, instability and symptoms that may be associated with neurovascular compromise. Once defined, the component parts of the SSMP are then applied while the patient performs the symptom-provoking movements, activities or postures to determine if an immediate change is achievable. This type of ‘real-time’ process has been recommended previously,23 ,24 and evidence (albeit limited) suggests that procedures found to improve symptoms in the cervical and lumbar regions within a session may be useful in guiding treatment selection and may help predict between-session changes in symptoms.27–29
The SSMP comprises three main sections. The first section aims to assess the relationship between thoracic posture and symptoms, the second aims to evaluate the effect of scapular position on symptoms and the third aims to assess the effect of the relationship between the humeral head and scapula on symptoms. In reality, the assessment procedures do not isolate one structure. For example, reducing the thoracic kyphosis also relatively posteriorly tilts the scapula, changes length-tension relationships of muscles, tendons and related soft tissues and may influence joint biomechanics. As all procedures involve touch, another reason for perceiving a change in symptoms may be the experience of this sensation.30 Additionally, there is only very limited evidence that humeral head procedures actually influence humeral head position.31
The SSMP assessment form is detailed in figure 1. The specific assessment procedures have been described elsewhere.10 ,11 ,13 Following agreement between both parties, the person with shoulder symptoms informs the clinician if an individual procedure: partially or completely alleviates symptoms; has no change on symptoms; or makes the symptoms worse. Techniques may be combined; for example, if reducing the thoracic kyphosis and elevating the scapula independently partially reduce symptoms, then the clinician may assess the response of combining both these procedures. If the SSMP completely and consistently alleviates symptoms, then the procedures found to alleviate the symptoms are used to inform treatment.
It is important for clinicians to appreciate that the SSMP is not a stand-alone procedure and if the SSMP does not change symptoms or only partially alleviates them, other rehabilitation based on the clinician's clinical reasoning and the patient's acceptance of that management need to be considered, such as advice, education, rotator cuff rehabilitation exercises,11 ,13 injection therapy or surgery.32 ,33
Although in clinical use,11 the reliability of the SSMP is uncertain. The primary aim of this investigation was to evaluate the intertester reliability of clinicians in determining how people with shoulder symptoms respond to SSMP procedures. The secondary aim was to investigate the differences in reliability between those that participated in long training (over 1 day) and short training (3 hours) in the SSMP. GRAAS recommendations for reporting reliability studies were used as a guide.34