Comparison of Muscle Atrophy After Direct Anterior & Posterior Total Hip Arthroplasty

Study Overview
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Brief Summary
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This project is designed to use MRI to evaluate pre- and post-arthroplasty hips; the specific aims of this project are three-fold. First, the investigators intend to compare the amount of muscle atrophy and tendon damage that occurs around the hip between two commonly-used operative approaches: the direct-anterior approach and the posterior approach. Second, the investigators aim to provide baseline data on the amount of muscle atrophy and tendon damage that should reasonably be expected to occur with both of these approaches. Third, the investigators will document the degree of recovery of the periprosthetic soft tissues post-surgery in both patient groups. The investigators first hypothesis is that the posterior approach will demonstrate significantly more damage to the abductors, piriformis, and short external rotators than the direct anterior approach, which will demonstrate minimal soft tissue damage. The investigators second hypothesis is that both surgical approaches will cause some degree of baseline muscle damage and atrophy, in a predictable pattern. The investigators third hypothesis is that each of the surgical approaches inherently cause some degree of soft tissue damage, and that the periprosthetic soft tissues that are incised during the surgical exposure will recover in a predictable pattern which is consistent but unique within each group

Official Title
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The Influence of Operative Approach on Muscle Atrophy After Total Hip Arthroplasty: A Comparison of Anterior and Posterior Approaches

Conditions
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Osteoarthritis, Hip

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients undergoing elective, primary total hip arthroplasty Use of Cementless Total Hip components Preoperative diagnosis of degenerative joint disease secondary to osteoarthritis Exclusion Criteria: Prior surgery on the affected hip No implanted medical devices or metallic debris in the patient which will preclude use of MRI patients must be able to participate in standard post-arthroplasty rehabilitation protocols.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 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 |
| --- | --- |
| Direct Anterior Approach<br> | |
| Posterior Approach<br> | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change from baseline in muscle volume at 6 weeks | Muscle volume will be recorded in MRI images with specialized software (external rotators,tensor fascia lata, rectus femoris,gluteus medius and minimus) | 6 weeks after surgery | 
| Change from baseline in muscle volume at 6 months |  | 6 months after surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Fatty atrophy of muscles from baseline at 6weeks | Qualitative assessment of fatty atrophy | 6 weeks after surgery | 
| tendon damage | Qualitative assessment of tendon damage on MRI | 6 weeks after surgery | 
| Change in fatty atrophy of muscles from baseline at 6 months |  | 6 months after surgery | 
| Tendon damage |  | 6 months after surgery |