Preoperative Gluteal Muscle Atrophy: A Silent Predictor of THA Dislocation.

This study looks at how fat buildup in hip muscles relates to hip osteoarthritis and less favorable recovery after hip replacement surgery. While it is known that weak gluteal muscles might cause problems, it is not yet proven if this specifically leads to hip dislocation after surgery. The goal of this study is to compare fat buildup in gluteal muscles between patients who had a hip dislocation soon after surgery and those who did not.

Study Overview

• Status: Completed
• Conditions: Total Hip Arthroplasty; Dislocation; Muscle Degeneration
• Intervention / Treatment: Diagnostic test: Dislocation; Diagnostic test: No dislocation

• Study Type: Observational
• Enrollment (Actual): 72

Contacts and Locations

Study Locations

• France
  • Gard
    • Nîmes, Gard, France, 30900
      • CHU Nîmes

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Patients following THA at Nimes university hospital

Description

Inclusion Criteria:

• primary THA with preoperative CT-scan

Exclusion Criteria:

• malposition of acetabular implants outside the Lewinneck safe zone,
• neurological or cognitive disorders,
• associated spinal pathologies (within the context of a hip-spine syndrome),
• chronic alcoholism,
• aseptic osteonecrosis,
• revision surgeries,
• late dislocations attributed to polyethylene wear,
• replacement following post-traumatic coxarthrosis due to acetabulum injuries.
• diameters of the prosthetic heads ≠ 32mm

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Dislocation group; Patients who underwent primary total hip arthroplasty with preoperative CT-scan and encountered an episode of dislocation.	Diagnostic test: Dislocation; One episode of total hip dislocation diagnozied on Xray within 2 years of surgery
Control group; Patients underwent primary total hip arthroplasty with preoperative CT-scan, who did not experience any episodes of dislocation within two years post-surgery, adhering to the previously outlined exclusion criteria (group control).	Diagnostic test: No dislocation; No experience of dislocation within two years post-surgery

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Mean Attenuation Ratio	The mean attenuation ratio (MAR), representing muscle fat degeneration, corresponds to the mean grayscale pixels in the selected area, expressed in Hounsfield Units (HU). Subsequently, the segmentation process was applied, selectively retaining pixels within the range of -30 HU to 150 HU. This range corresponds to muscle fibers and intramuscular fat, effectively excluding extra-fascial fat and bone pixels.	The CT scan of the pelvis used to plan the operation is performed between one and two months before the surgery.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Cross-Sectional Area	The cross-sectional area (CSA), measured in square centimeters (cm²) defines the average muscle surface area.	The CT scan of the pelvis used to plan the operation is performed between one and two months before the surgery.
Intramuscular Fatty Fraction	Finally, the intramuscular fatty fraction (IFF) or percentage of intramuscular fat was calculated using the IB Delta Suite plug-in with thresholds of -30/0/150. Pixels below -30 HU and above 150 HU were designated as extra-muscular, while pixels ranging between 0 HU and 150 HU represented muscle fibers. Pixels falling between -30 HU and 0 HU denoted intramuscular fat, constituting the IFF.	The CT scan of the pelvis used to plan the operation is performed between one and two months before the surgery.

Collaborators and Investigators

• Sponsor: Centre Hospitalier Universitaire de Nīmes

Study record dates

Study Major Dates

• Study Start (Actual): January 1, 2020
• Primary Completion (Actual): March 1, 2021
• Study Completion (Actual): May 1, 2023

Study Registration Dates

• First Submitted: August 23, 2024
• First Submitted That Met QC Criteria: August 23, 2024
• First Posted (Actual): August 26, 2024

Study Record Updates

• Last Update Posted (Actual): August 26, 2024
• Last Update Submitted That Met QC Criteria: August 23, 2024
• Last Verified: August 1, 2024

More Information

Terms related to this study

• Keywords: CT; Total Hip Arthroplasty; Muscle Fatty Degeneration; Gluteal Muscles
• Additional Relevant MeSH Terms: Nervous System Diseases; Neurologic Manifestations; Wounds and Injuries; Joint Diseases; Musculoskeletal Diseases; Neuromuscular Manifestations; Pathological Conditions, Anatomical; Muscular Atrophy; Joint Dislocations; Atrophy
• Other Study ID Numbers: THAdislocation glutealatrophy

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No