Nonoperative Management of Shoulder Instability

Non-operative management following a shoulder dislocation or subluxation remains a challenging and complex task. Accurate diagnosis of the condition, and shared decision-making regarding operative and non-operative management, as well as timing of return to play is required. This clinical concept paper introduces a shoulder instability framework that addresses these fundamental clinical dilemmas. Valid clinical prognostic tools which can predict recurrent shoulder instability are reviewed. The process of shared decision-making within the realm of shoulder instability is also presented. Finally, a framework for progressive rehabilitation that addresses deficits in motor control, strength, and endurance in scapula and shoulder musculature is presented to guide patients from an initial instability event, through to return to play

Line Hops and Side Hold Rotation Tests Load Both Anterior and Posterior Shoulder: A Biomechanical Study

Background: Clinical tests should replicate the stressful positions encountered during sport participation. Evaluating the kinetic and electromyographical demands of clinical tests enables clinicians to choose appropriate tests for specific sports. Purpose: To describe the shoulder forces and muscle activation levels during closed chain functional tests of Line Hops (LH) and Side Hold Rotation (SHR). Study Design: Descriptive biomechanical study. Methods: Ten asymptomatic participants were examined in a university laboratory. Two functional tests were evaluated using three-dimensional video analysis and electromyography to measure shoulder forces, moments, and muscular activity levels. Results: SHR produced a peak average posterior translation force of 4.84 N/kg (CI95 4.32-5.36N/kg) and a peak average anterior translational force of 1.57 N/kg (CI95 1.10-2.01N/kg). High levels of serratus anterior (98% maximum voluntary isometric contraction (MVIC) and infraspinatus (52 %MVIC) were recorded during SHR. LH produced a posterior translational force of 4.25 N/kg (CI95 3.44–5.06N/kg). High levels of serratus anterior (105 %MVIC) and infraspinatus (87 %MVIC) were recorded during the push off phase of this activity. Conclusions: LH and SHR placed large posterior translational forces that approached half of a person\u27s bodyweight on shoulder structures. SHR produced an anterior translation force at extremes of horizontal abduction placing approximately 18% of bodyweight on shoulder structures. The LH test required the serratus anterior to provide power to push the upper torso of the ground while both the serratus and the infraspinatus provides scapular and humeral stability, respectively. Level of Evidence: 4: Case series

Line Hops and Side Hold Rotation Tests Load Both Anterior and Posterior Shoulder: A Biomechanical Study

# Background Clinical tests should replicate the stressful positions encountered during sport participation. Evaluating the kinetic and electromyographical demands of clinical tests enables clinicians to choose appropriate tests for specific sports. # Purpose To describe the shoulder forces and muscle activation levels during closed chain functional tests of Line Hops (LH) and Side Hold Rotation (SHR). # Study Design Descriptive biomechanical study # Methods Ten asymptomatic participants were examined in a university laboratory. Two functional tests were evaluated using three-dimensional video analysis and electromyography to measure shoulder forces, moments, and muscular activity levels. # Results SHR produced a peak average posterior translation force of 4.84 N/kg (CI~95~ 4.32-5.36N/kg) and a peak average anterior translational force of 1.57 N/kg (CI~95~ 1.10-2.01N/kg). High levels of serratus anterior (98% maximum voluntary isometric contraction (MVIC) and infraspinatus (52 %MVIC) were recorded during SHR. LH produced a posterior translational force of 4.25 N/kg (CI~95~ 3.44–5.06N/kg). High levels of serratus anterior (105 %MVIC) and infraspinatus (87 %MVIC) were recorded during the push off phase of this activity. # Conclusions LH and SHR placed large posterior translational forces that approached half of a person’s bodyweight on shoulder structures. SHR produced an anterior translation force at extremes of horizontal abduction placing approximately 18% of bodyweight on shoulder structures. The LH test required the serratus anterior to provide power to push the upper torso of the ground while both the serratus and the infraspinatus provides scapular and humeral stability, respectively. # Level of Evidence 4: Case serie

The supine moving apprehension test—Reliability and validity among healthy individuals and patients with anterior shoulder instability

Background: Performance-based tests for patients with anterior shoulder dislocation are lacking. This study determined the reliability and validity of the supine moving apprehension test designed to assess the ability to control anterior instability loads. Methods: Thirty-six participants were recruited (18 healthy individuals, and 18 patients following anterior shoulder dislocation). Healthy participants performed the supine moving apprehension test on 2 separate occasions to determine test-retest reliability. Patients completed the supine moving apprehension test and the Western Ontario Shoulder Instability index before and 6 months after surgical stabilization of their shoulder. The presence of anterior apprehension was also documented post-operatively. Results: The supine moving apprehension test demonstrated good test-retest reliability (intraclass correlation coefficient =0.74−0.84). Patients performed 18−30 repetitions less than healthy individuals during the supine moving apprehension test (P \u3c 0.01). A strong correlation was found between supine moving apprehension test scores and Western Ontario Shoulder Instability post-operatively (r=−0.74, P ≤ 0.01). Supine moving apprehension test scores significantly improved among patients following surgery (P \u3c 0.01). Patients with a negative apprehension test post-operatively performed the supine moving apprehension test significantly better than patients with a positive apprehension test (P \u3c 0.01). Conclusions: The supine moving apprehension test is reliable and valid among patients with anterior shoulder dislocation and may serve to assess patients’ ability to control shoulder anterior instability loads