Neuromonitoring During the Latarjet Procedure

Study Overview
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Brief Summary
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In a study performed by the Harvard Shoulder Service, it has been documented that there is a significant incidence of neurologic complications of the Latarjet procedure for shoulder instability. 5 out of 52 patients had neurologic complaints post-operatively. 3 of these nerve palsies were transient, however 2 had not yet recovered fully at time of latest follow-up and returned to the operating room for exploration and neurolysis of the axillary nerve and brachial plexus. By using intra-operative neuromonitoring to determine exactly when there is a potential nerve injury during the procedure, the investigators will be able to modify what the investigators do at that step of the procedure, in order to decrease or possibly even eliminate the risk of neurologic injury.

Detailed Description
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The investigators propose to study the intra-operative events which put nerves at risk during the Latarjet procedure. By using neuromonitoring to determine exactly when there is a potential nerve injury during the procedure, the investigators will be able to modify what the investigators do at that step of the procedure, in order to decrease or possibly even eliminate the risk of neurologic injury. Modifications to our surgical technique in response to events observed on neuromonitoring would include repositioning the operative shoulder and upper extremity, and repositioning or removing retractors. The investigators believe this would lead to a significant decrease in the incidence of neurologic complications post-operatively. Since this operation is usually performed on young, active patients, the benefits of reducing or eliminating these complications would have a far-reaching impact both for the individual and for society. Above all, the investigators feel that this is an important patient safety initiative.

Official Title
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Neuromonitoring During the Latarjet Procedure

Conditions
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Shoulder Instability, Iatrogenic Nerve Injury

Intervention / Treatment
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* Device: Intra-operative neuromonitoring (XLTEK/NATUS EP Protektor)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: All patients of the two senior surgeons who will undergo the Latarjet procedure for shoulder instability will be considered for inclusion in the study. Our patients who have received prior approval from their insurance carrier to cover neuromonitoring during the surgical procedure will be enrolled. Exclusion Criteria: Relative contraindications to transcranial electrical stimulation include: history of seizures, significant brain trauma, cerebral edema with mass effect, recent CVA, intracerebral devices (e.g., shunts, aneurysmal clips), skull defect and cardiac pacemaker. Patients with there conditions will be included in the study.

Ages Eligible for Study
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Minimum Age: 14 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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Design Details

Primary Purpose: Prevention
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Intra-op neuromonitoring<br> | Device: Intra-operative neuromonitoring (XLTEK/NATUS EP Protektor)<br>* Device: Intra-operative neuromonitoring A XLTEK/NATUS EP Protektor machine (at MGH) or a Cadwell Cascade Elite neuromonitoring machine (at BWH), both FDA approved for intra-operative neuromonitoring, will deliver the electrical stimulus applied transcranially to stimulate the motor cortex, while motor evoked responses will be recorded from different myotomes from both upper limbs. Also the same equipment will deliver electrical stimulus to stimulate peripherally the median and ulnar nerves at the wrists, with recording of the thalamocortical potentials in the scalp channels.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Neurologic Complication Rate After Latarjet Procedure | Nerve palsy of any nerve(s) in the operative upper extremity. | up to 24 weeks after the procedure | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Shoulder instability, Latarjet procedure, Nerve injury