The Effect of Arthroscopic Bankart Repair on Anterior-posterior Glenohumeral Translation and Shoulder Proprioception in Patients With Traumatic Anterior Shoulder Instability: a Prospective Cohort Study

Study Overview
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Brief Summary
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The purpose of the study is to investigate biomechanical and proprioceptive conditions in patients with symptomatic traumatic anterior shoulder instability undergoing arthroscopic Bankart repair. To determine these, non-invasive and non-irradiating examination methods that have been proven valid and reliable will be used in a combination that has not been reported before. The objective is to determine whether the anatomical reconstruction affects biomechanical and proprioceptive measures in the traumatic unstable shoulder. The study will also investigate the correlations between biomechanics and proprioception and patients' functional outcomes and range of motion. The hypotheses are that the intervention improves biomechanical and proprioceptive conditions to the near-normal state, as measured after both 6 and 12 months. Further, hypotheses are that there are positive correlations between improved biomechanical and proprioceptive measures and both patients' functional outcomes and range of motion.

Detailed Description
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• Aim: To investigate the effect of arthroscopic Bankart repair on shoulder biomechanics and proprioception, and increase understanding of traumatic anterior shoulder instability. Main research questions: A (biomechanics): Does arthroscopic Bankart repair have a stabilising effect on the anterior-posterior glenohumeral translation in patients with traumatic anterior shoulder instability? B (proprioception): Does arthroscopic Bankart repair improve neuromuscular control in patients with traumatic anterior shoulder instability? Objectives and hypotheses research question A: In patients with traumatic anterior shoulder instability undergoing arthroscopic Bankart repair, to investigate the anterior-posterior glenohumeral translation and the scapular rotations before and six and twelve months after surgery and whether the ranges are restored to the same as the non-injured contralateral shoulder. Hypotheses: Arthroscopic Bankart repair results in a ≥2.5 mm decrease in anterior-posterior glenohumeral translation, remaining both six and twelve months after surgery. Arthroscopic Bankart repair reduces anterior-posterior glenohumeral translation to the same range as measured in the non-injured shoulder (±2.5 mm). Arthroscopic Bankart repair reduces superior-inferior glenohumeral translation significantly, as measured six and twelve months after surgery. Scapular rotations and tilt remain unchanged after arthroscopic Bankart repair. Objectives and hypotheses research question B: In patients with traumatic anterior shoulder instability undergoing arthroscopic Bankart repair, to investigate the neuromuscular control before and six and twelve months after surgery and whether the neuromuscular control is restored to the same level as the non-injured contralateral shoulder. Hypotheses: Arthroscopic Bankart repair improves neuromuscular control, remaining both six and twelve months after surgery. Arthroscopic Bankart repair improves neuromuscular control to the same range as the non-injured shoulder. Other objectives: In patients with traumatic anterior shoulder instability undergoing arthroscopic Bankart repair: To determine the recurrence rates (radiographically confirmed or manually reduced dislocation) in the first twelve months after surgery. To investigate the shoulder range of motion (ROM) before and six and twelve months after surgery. To assess the joint instability by manual testing before and six and twelve months after surgery. To quantify potential bone loss before surgery. To investigate patient-reported outcome measures (PROM) before and six and twelve months after surgery. To investigate if there are correlations between a) the shoulder biomechanics and b) the neuromuscular control, and PROM, ROM, and bone loss, respectively. Type of study: Multi-clinical prospective cohort study including 55 patients. Patients' contralateral shoulders will be used as controls. • Time schedule: Recruitment and inclusion is planned to begin 1 March 2022 and is expected to last for twelve months. With a one-year follow-up the complete study period is expected to last two years. • Set-up: Five sports orthopaedics clinics in the Capital Region of Denmark will recruit patients for the study. While the responsibility for treatment remains at the recruiting center, all study-related activities will take place at the Copenhagen University Hospital Hvidovre. Patients who have signed an informed consent form will undergo examinations prior to, as well as six and twelve months after surgery. All examinations will include biomechanical and proprioceptive testing, accompanied by a clinical shoulder examination and two validated electronic questionnaires regarding shoulder-related function and quality of life. A pre-interventional 3D computed tomography scan will be performed to evaluate bone loss. Study participation will not influence the treatment course.

Official Title
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The Effect of Arthroscopic Bankart Repair on Anterior-posterior Glenohumeral Translation and Shoulder Proprioception in Patients With Traumatic Anterior Shoulder Instability: a Prospective Cohort Study

Conditions
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Shoulder Dislocation

Intervention / Treatment
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* Procedure: Arthroscopic Bankart repair


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 18-40 years Unilateral traumatic anterior shoulder instability booked for arthroscopic Bankart repair according to the department's guidelines (extent of symptoms, suffer recurrent dislocations, positive apprehension and relocation test, limited bone loss) Willing to adhere to the study protocol, herein attend follow-up The patient must be able to speak and understand Danish The patient must be able to give written informed consent Exclusion Criteria: Traumatic instability in the opposite shoulder For one or both shoulders: posterior, multi-directional or atraumatic instability For one or both shoulders: traumatic rotator cuff or biceps tendon tear, Superior Labrum from Anterior to Posterior tear (SLAP-lesion) For one or both shoulders: traumatic fracture of proximal humerus (other than Hill-Sachs lesion), clavicula, scapula (other than glenoid) or dislocation of sternoclavicular or acromioclavicular joints For one or both shoulders: atraumatic shoulder pathologies (e.g. frozen shoulder, symptomatic osteoarthritis of the shoulder or acromioclavicular joints, acute calcific tendinitis) Pregnancy Terminal illness or severe medical illness: American Society of Anesthesiology (ASA) score ≥3.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 40 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Patient group<br>Patients aged 18-40 years with symptomatic unilateral traumatic anterior shoulder instability, due to dislocation or subluxation, scheduled for arthroscopic Bankart repair. The study is not interventional but observational, examining biomechanical and proprioceptive conditions in patients' unstable shoulders before and after the surgical procedure. | Procedure: Arthroscopic Bankart repair<br>* Arthroscopic Bankart repair is a minimally invasive surgical procedure with the aim to reattach and tighten the detached labrum and ligaments within the shoulder joint.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in anterior-posterior glenohumeral translation (range in millimeters) | The effect of Bankart repair on anterior-posterior glenohumeral translation, measured 6 months after intervention and compared to pre-interventional. The translation will be measured using ultrasound examination. | baseline, 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in anterior-posterior glenohumeral translation (range in millimeters) | Longer-term effects of Bankart repair on anterior-posterior glenohumeral translation, as measured 12 months after intervention and compared to pre-interventional. The translation will be measured using ultrasound examination. | baseline, 12 months | 
| Change in neuromuscular control (as assessed with the Copenhagen Assessment of Neuromuscular Control in the Unstable Shoulder (CANCUS) protocol). | The effect of Bankart repair on neuromuscular control at 6 and 12 months after intervention and compared to pre-interventional. Neuromuscular control will be assessed using the Copenhagen Assessment of Neuromuscular Control in the Unstable Shoulder (CANCUS) protocol. | baseline, 6 months, 12 months | 
| Change in superior-inferior glenohumeral translation (range in millimeters) | Effects of Bankart repair on superior-inferior glenohumeral translation, measured 6 and 12 months after intervention and compared to pre-interventional. | baseline, 6 months, 12 months | 
| Change in scapular rotations (degrees) | Effects of Bankart repair on scapular rotations, measured 6 and 12 months after intervention and compared to pre-interventional. | baseline, 6 months, 12 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Traumatic anterior shoulder instability, Shoulder dislocation, Glenohumeral instability, Glenohumeral biomechanics, Shoulder biomechanics, Glenohumeral translation