Comparing Outcomes of Elbow Extension Tendon Transfers

Study Overview
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Brief Summary
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Active elbow extension has significant functional benefits for individuals with tetraplegia. The proposed work will provide information to assess how effectively people are using their elbow extension tendon transfers, and whether one surgery works more effectively than the other. This study will provide recommendations to clinicians about the possibility of improving function after surgery using rehab techniques.

Detailed Description
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Voluntary control of elbow extension significantly improves functional abilities for individuals with tetraplegia. As a result, surgical reconstruction of elbow extension via tendon transfer is considered a fundamental intervention that benefits the patient, even if other tendon transfers aimed at improving hand function are never performed. Presently, there are two common tendon transfer surgeries used to restore elbow extension following spinal cord injury. These are the posterior deltoid to triceps transfer and the biceps to triceps transfer. Both surgeries significantly improve voluntary elbow extension, although there is variability in the amount of control that is restored among patients. This study will directly compare the performance of the posterior deltoid transfer to the biceps transfer with regard to: voluntary elbow extension strength, the ability to activate the transfer, and neural factors associated with voluntary and involuntary control of individual muscles. These comparisons will be made in functionally relevant postures and will provide fundamental information that will improve clinical understanding of the capacity of each of these two procedures to restore elbow extension. The fundamental hypothesis of this proposal is that an inability to maximally activate the transferred posterior deltoid and the transferred biceps significantly limits the elbow extension moment that can be produced.

Official Title
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A Comparison of Two Surgical Procedures That Restore Elbow Extension

Conditions
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Cervical Spinal Cord Injury

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Cervical Spinal Cord Injury (C5-C7) Posterior Deltoid to Triceps Tendon Transfer at least one year post-surgery Biceps to Triceps Tendon Transfer at least one year post-surgery Exclusion Criteria: Subjects will be excluded from the studies if there is presence of concurrent severe medical illness, including: unhealed decubiti use of baclofen pumps existing infection cardiovascular disease significant osteoporosis (as indicated by a history of fractures following injury) or a history of pulmonary complications or autonomic dysreflexia

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 60 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 |
| --- | --- |
| Group 1<br>Subjects with posterior deltoid-to-triceps tendon transfers | |
| Group 2<br>Subjects with biceps-to-triceps tendon transfers | |
| Group 3<br>Subjects with cervical SCI who have not had tendon transfers | |
| Group 4<br>Unimpaired control subjects | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Elbow Extension Strength | Elbow extension strength was measured as the maximum elbow extension moment that subject's could generate. We used an elbow moment transducer to measure elbow moments under isometric (no change in arm posture) conditions. Subjects performed three trials at maximum effort, holding maximum elbow extension for 5 to 7 seconds. The maximum moment was computed as the maximum average moment sustained over a 0.5 second window. | At least one year post surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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tendon transfer, elbow