Direct Superior Approach (DSA) vs Posterior Approach (PA) in THA

A Prospective Randomised Controlled Trial Comparing the Direct Superior Approach Versus the Posterior Approach for Total Hip Arthroplasty

Total Hip Arthroplasty (THA) is a highly effective treatment for patients with symptomatic hip osteoarthritis. The surgical approach in THA is important as it influences postoperative clinical recovery, functional outcomes, and implant positioning [1]. The evolution of surgical techniques in THA has led to the development of minimally invasive surgery, which is performed through smaller skin incisions, reduced soft tissue disruption and greater muscle preservation [2-10]. This prospective, randomised control study compares clinical and radiological outcomes in THA performed using the standard posterior approach (PA) and its less invasive modification, the direct superior approach (DSA). The study will include 80 patients with hip osteoarthritis undergoing THA. Following informed consent, patients will be randomised to one of the two treatment groups, and undergo THA using either the PA or DSA. The control group includes patients undergoing THA through the PA while the investigation group includes patients undergoing THA with the DSA. A further 25 patients randomly selected from each treatment group will undergo radiosteriometric analysis (RSA) to assess differences in early implant migration between PA and DSA groups.

Clinical and radiological outcomes of interest will be recorded by blinded observers at regular intervals for 2 years after surgery. The findings of this study will enable an improved understanding of differences in postoperative clinical recovery, functional outcomes, and implant positioning in THA performed using the DSA compared to the PA approach.

Study Overview

• Status: Completed
• Conditions: Surgery; Patient Satisfaction; Surgical Incision
• Intervention / Treatment: Device: Total hip arthroplasty

• Study Type: Interventional
• Enrollment (Actual): 80
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United Kingdom
  • London, United Kingdom, NW1 2PG
    • University College London Hospital NHS Foundation Trust

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 80 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Patient has hip osteoarthritis requiring primary THA

  • Patient and surgeon are in agreement that THA is the most appropriate treatment
  • Patient is fit for surgical intervention following review by surgeon and anaesthetist
  • Patient age: Patients 18-80 years of age inclusive
  • Gender: male and female
  • Patient must be capable of giving informed consent and agree to comply with the postoperative review program
  • Patient must be a permanent resident in an area accessible to the study site
  • Patient must have sufficient postoperative mobility to attend follow-up clinics and allow for radiographs to be taken

Exclusion Criteria:

• Patient is not suitable for primary THA e.g. patient requires revision surgery for previously failed THA

  • Patient is not medically fit for surgical intervention
  • Patients under the age of 18 or over 80 years of age
  • Patient is immobile or has another neurological condition affecting musculoskeletal function
  • Patient is already enrolled on another concurrent clinical trial
  • Patient is unable or unwilling to sign the informed consent form specific to this study
  • Patient is unable to attend the follow-up programme
  • Patient is non-resident in local area or expected to leave the catchment area postoperatively

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Direct Superior Approach (DSA); Direct superior incision during surgery	Device: Total hip arthroplasty; Surgical intervention designed to replace arthritic joint with artificial implant
Active Comparator: Posterior Approach (PA); Posterior approach incision during surgery	Device: Total hip arthroplasty; Surgical intervention designed to replace arthritic joint with artificial implant

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Pain in hip at 24 hours following surgery	Pain at 24 hours following surgery as assessed using the visual analogue scale between patients undergoing PA for THA versus DSA for THA.	24 hours

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Operating time	Operating time in minutes	During the operation
Time to discharge	Time to discharge in hours	6 weeks post operation
Analgesia requirements	Analgesia requirements	inpatient admission and postoperatively at 6 weeks, 6 months, 1 year and 2 years.
Oxford Hip Score (OHS)	Patient recorded outcome measure via questionnaire. 48 is best score and 0 worst score	Pre-op; 6 weeks post-op; 6 months post-op; 1 year post-op; 2 years post-op
Hip injury and osteoarthritis outcome score (KOOS)	Patient recorded outcome measure via questionnaire. 6 separate domains including pain, stiffness, quality of life, symptoms, and function; each domain creates percentage with overall cumulative percentage achieved; best score 100%	Pre-op; 6 weeks post-op; 6 months post-op; 1 year post-op; 2 years post-op
European Quality of Life questionnaire with 5 dimensions for adults (EQ-5D)	Patient recorded outcome measure with 5 domains; score -1 to 1, with 1 being best score	Pre-op; 6 weeks post-op; 6 months post-op; 1 year post-op; 2 years post-op
Harris Hip Score [HHS]	Patient recorded outcome measure via questionnaire. Scored 0-100 with 100 best possible outcome	Pre-op; 6 weeks post-op; 6 months post-op; 1 year post-op; 2 years post-op
Mobilisation distance	Mobilisation distance in metres	inpatient admission and postoperatively at 6 weeks, 6 months, 1 year and 2 years.
Use of mobility aids	Use of mobility aids	inpatient admission and postoperatively at 6 weeks, 6 months, 1 year and 2 years.
Femoral and acetabular implant early migration	Femoral and acetabular implant early migration as assessed using radiosteriometric analysis (RSA) This RSA will be performed on a cohort of 25 randomly selected patients from each treatment group.	postoperatively at 2 weeks, 6 weeks, 6 months, 1 year, and 2 years.

Collaborators and Investigators

• Sponsor: University College, London

Publications and helpful links

General Publications

• Kayani B, Konan S, Tahmassebi J, Ayuob A, Haddad FS. The direct superior approach versus posterior approach for total hip arthroplasty: study protocol for a prospective double-blinded randomised control trial. Trials. 2020 Jun 19;21(1):546. doi: 10.1186/s13063-020-04484-y.

Study record dates

Study Major Dates

• Study Start (Actual): June 12, 2018
• Primary Completion (Actual): December 31, 2021
• Study Completion (Actual): December 31, 2022

Study Registration Dates

• First Submitted: December 6, 2019
• First Submitted That Met QC Criteria: December 6, 2019
• First Posted (Actual): December 10, 2019

Study Record Updates

• Last Update Posted (Actual): June 28, 2023
• Last Update Submitted That Met QC Criteria: June 27, 2023
• Last Verified: June 1, 2023

More Information

Terms related to this study

• Keywords: Osteoarthritis; Total hip arthroplasty; Minimally invasive surgery; Implant position; Direct superior approach; Posterior approach; Radiostereometric analysis
• Additional Relevant MeSH Terms: Wounds and Injuries; Surgical Wound
• Other Study ID Numbers: 17/0426

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: No plans

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: Yes
• product manufactured in and exported from the U.S.: Yes