The Role of Surgical Approach on Residual Limping After Total Hip Arthroplasty

Study Overview
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Brief Summary
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Residual limping after total hip arthroplasty is empirically associated with the use of lateral approach but has been reported in litterature even with the use of posterior approach. The purpose of this clinical trial is to compare the risk of residual limping one year after total hip arthropasty between lateral and posterior approach.

Detailed Description
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The use of lateral approach has been empirically associated with increased risk of abductor insufficiency and limping after total hip arthroplasty compared with the posterior approach. However lateral approach remains a widespread technik because it provides a decreased risk of dislocation. In litterature, gluteus medius insufficiency has been reported even when the posterior approach has been used. In the early stage of postperative relhabilitation it is difficult to distinguish between between limping that resolves after abductor training and limping due to abductor injury/avulsion that is resistent to physiotherapy. The purpose of this randomized controlled trial is to compare the risk of persistent limping one year after total hip arthtoplasty between lateral and posterior approach and to identify patient-related risk factors for limping. Moreover it will validate ultra sound (U/S), magnetic resonance imaging (MRI) of the hip and gait analysis as diagnostic tools for early detection of limping that is going to persist one year after total hip arthroplasty. 580 patients will hip osteoarthritis be randomised to receive their total hip arthroplasty through an either lateral of posterior approach and will be followed at one year with physical examination (Trendelenburg sign) and patient.-reported outcome measures. Patients with a positive Trendelenburg sign at 3 months will undergo U/S and MRI examination as well as gait analysis and reassessed at one year with physical examination. The first 40 patients with negative Trendelenburg sign at 3 months will also undergo U/S, MRI and gait analysis. The specificity and sensitivity of U/S, MRI and gait analysis for positiv Trendelenburg sign will be calculated.

Official Title
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Abductor Insufficiency After Total Hip Arthroplasty; Risk Factors and Diagnosis

Conditions
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Muscle Weakness, Hip Osteoarthritis, Muscle Atrophy, Muscle Injury, Arthroplasty Complications

Intervention / Treatment
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* Procedure: Lateral approach
* Procedure: Posterior approach


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Primary unilateral osteoarthritis of the hip scheduled for total hip arthroplasty. Ability to understand and write swedish. Exclusion Criteria: Impaired funktion of the contralateral hip or knees causing limping. Neuromuscular diseases Postoperative leg length discrepancy excceding 1 cm Postoperative discrepancy in femoral offset exceeding 25% of the femoral offset of the contralateral hip.

Ages Eligible for Study
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Minimum Age: 40 Years
Maximum Age: 80 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: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Randomized controlled trial
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Lateral approach<br>290 participants receive their hip prosthesis through a lateral approach. The anterior third of m. gluteus medius along with the corresponding part of m. vastus lateralis are detached from the greater trochanter and the anterior capsule is excised for the exposure of the hip joint. After implant insertion, the gluteus medius is reinserted into the greater trochanter with non-absorbable sutures. Participants are followed at three and 12 months by a physiotherapist. | Procedure: Lateral approach<br>* Total hip arthroplasty performed through a lateral surgical approach (Gammer)<br>* Other names: Gammer approach;|
| Active Comparator: Posterior approach<br>290 participants receive their hip prosthesis through a posterior approach. The m. piriformis gemelli and obturator internus are detached from the greater trochanter and the posterior capsule is incised for the exposure of the hip joint. After implant insertion, the posterior capsule as well as m piriformis and the external rotators are reinserted into the greater trochanter with non-absorbable sutures. Participants are followed at three and 12 months by a physiotherapist. | Procedure: Posterior approach<br>* Total hip arthroplasty performed through a posterior surgical approach (Moore)<br>* Other names: Moore approach;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Trendelenburg sign as binary variable (positive/negative) | Trendelenburg sign negative if the pelvis remains horisontal while standing only on the operated leg with both arms in anatomical postion. If the pelvismcannot be kept horisontal and tilts towards the kontralateral hip the Trendelenburgs sign is regarded as positive. | At 12 months after intervention | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Dislocation | Incidens of postoperative dislocation | Within 12 months from intervention | 
| Intraoperative blood loss | Bleeding during total hip arthroplasty measured in ml | Intraoperative | 
| Periprosthetic infection | Incidens of deep surgical wound infection | Within 12 months from intervention | 
| Oxford Hip Score | Patient-reported hip function measured in a scale of 0-48 | At 3 months after intervention | 
| Oxford Hip Score | Patient-reported hip function measured in a scale of 0-48 | At 12 months after intervention | 
| Euroqol 5 dimension 5 level index (EQ5D-5L) | Patient-reported health-related quality of life measured with the swedish version of euroqol 5 dimension 5 level index 0-1 | At 3 months after intervention | 
| Euroqol 5 dimension 5 level index (EQ5D-5L) | Patient-reported health-related quality of life measured with the swedish version of euroqol 5 dimension 5 level index 0-1 | At 12 months after intervention | 
| Euroqol visual analog scale (EQVAS) | Patient-reported health-related quality of life measured with the euroqol visual analog scale 0-100 | At 3 months after intervention | 
| Euroqol visual analog scale (EQVAS) | Patient-reported health-related quality of life measured with the euroqol visual analog scale 0-100 | At 12 months after intervention | 
| University of California Activity Level (UCLA) | Patient-reported acivity level measured with the University of California Level of Acivity rank scale 0-10 | At 3 months after intervention | 
| University of California Activity Level (UCLA) | Patient-reported acivity level measured with the University of California Level of Acivity rank scale 0-10 | At 12 months after intervention | 
| Gluteus medius avulsion in ultrasound | The proportion avulsed gluteus medius tendon in relation to the whole tendon attachment in a scale of 0 (no avulsion) to 1 (total avulsion). Measured with ultrasound | At 3 months after intervention | 
| Gluteus medius atrophy in Magnetic Resonance Imaging | The area of gluteus medius muscle in the operated side divided by the area of the gluteus medius muscle in the healthy side as shown in magnetic resonance imaging in a scale of 0 (complete atrophy) to 1 (no atrophy) | At 3 months after intervention | 
| Hip abuction torque | Hip abuction torque measured in Nm/Kg with gate analysis | At 3 months after intervention | 
| Trendelenburg sign as binary variable (positive/negative) | Trendelenburg sign negative if the pelvis remains horisontal while standing only on the operated leg with both arms in anatomical postion. If the pelvismcannot be kept horisontal and tilts towards the kontralateral hip the Trendelenburgs sign is regarded as positive. | At 3 months after intervention | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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abductor, approach, limp, Trendelenburg, gluteus medius