Total hip arthroplasty via the direct anterior approach versus lateral approach: study protocol for a randomized controlled trial

Abstract

Background and objectives: Total hip replacement is evolving to be more refined, especially through the development of muscle sparing approaches such as the direct anterior approach (DAA), bone preserving prosthesis, as well as the use of a fast tracking protocol. Despite the rising interest in the DAA, its attribute and benefits as a muscle sparing approach continue to be debated. While some advocates of this procedure report a faster recovery, lower postoperative pain levels and lower dislocation rates, there are some studies describing higher complication rates specific to the approach, longer setup and surgery time, as well as muscle damage similar to classic approaches, especially in complex cases. We aim to establish if the total hip replacement through the DAA results in lower muscle damage, faster recovery and better overall clinical outcomes when compared to the classic lateral approach. Design: This will be a single-center, single surgeon, randomized controlled trial. Methods: Two hundred patients diagnosed with end-stage primary degenerative hip arthritis confirmed on plain radiographs will be randomly assigned to undergo a primary total cementless hip arthroplasty via the direct anterior approach or the lateral approach. The primary goal of this study is to determine if the direct anterior approach is less invasive and if this yields superior clinical outcomes. Outcome measures: The primary outcome is muscle damage assessment using Myoglobin and Troponin as biomarkers. Secondary outcomes include functional outcome measures Oxford Hip Score, Harris Hip Score and quality of life 36-Item Short-Form Health Survey, physical recovery tests, complication rates, postoperative pain levels (daily for the 1st week and weekly for the first 3 months, as well as 6, 12 and 24 months after surgery), rescue medication consumption, prosthesis component positioning evaluated on radiographs, as well as perioperative data (i.e., surgery and setup time, incision length, blood loss, length of hospital stay, time to cessation of walking aids) and other biomarkers for muscle damage and inflammatory responses (i.e., creatine kinase, lactate dehydrogenase, aspartate aminotransferase and C-reactive protein). Discussion: This study represents a pursuit to provide an evidence based enquiry upon the muscle sparing benefits of the total hip replacement via the direct anterior approach relative to the lateral approach. Ethics and dissemination: This study was approved by the University of Medicine and Pharmacy Cluj-Napoca Ethics Committee (517/2015) and it will be performed in accordance with the guidelines of the Declaration of Helsinki. Written informed consent will be obtained from all patients prior to recruitment in this study. The results of the trial will be published in a peer-reviewed journal and will be disseminated via various forms of media. Trial registration: ClinicalTrial.gov identifier: NCT02719236.