Outcomes Following Anterior Approach to

Total Hip Arthroplasty:

A Multi-Centre Observational Study

The Anterior THA Collaborative

Investigative Team

• Anterior THA Research Collaborative • Chair: Joel M. Matta MD, St. John’s Hospital, Santa Monica• Secretary: Dave Dodgin MD, Walnut Creek, California• Research: Mohit Bhandari MD, McMaster University, Canada

• Participating Surgeons:• Gary Bradley MD, Santa Barbara, CA• Jim Grimes MD, Bakersfield, CA• John Masonis MD, Charlotte, NC• Stefan Kreuzer MD, Houston, TX• Andrew Yun MD, Inglewood, CA • Gary Matthys MD, Fargo, ND• Brian Jewett MD, Eugene,OR• Michael Bellino MD, Palo Alto, CA

Funding

• DePuy – Research Grant

• Not involved in Protocol Development, Data Management, Data Analysis or Decision to Publish

Methods

• Multi-center cohort study of adult participants with hip arthritis

• All surgically treated with anterior approach THA

Sample Size

• To have sufficient sample size to conduct regression analyses exploring baseline variables association (N=10) with the presence or absence of complications, we require approximately 100 events (ie. 10 events per variable included in the analysis). Given a plausible complication rate of 10%, we will require atleast 1000 patients for our study

• 9 Clinical Sites across United States

• 1152 Patients Included– 125 bilateral THAs

• 1277 THAs

RESULTS

Results

• Mean Age: 65 ±12.2 years

• Median BMI 26

• %Female: 53%

• %Caucasian: 92%

• %Retired: 46%

• %Osteoarthritis 93%

• % Bilateral THA 10%

Results

• Press-fit 94%

• 32mm head 50%

Results

• Median Follow Up: 1 year (max: 8 yrs)• Hospital Stay

– Median: 3 days– 25% discharged by 2 days– 80% discharged by 4 days

• Time to Discard Assistive Devices– Median 14 days

Results

• Dislocation Rate– 0.6% (95%CI: 0.3%-1.2%)

Complications: Technique

• Overall Rate: 2.5% (95% CI: 2.0%-3.6%)

– Greater Trochanteric Fracture 12 patients– Calcar split 7 patients– Femoral Shaft Fracture 8 patients– Infection 8 patients

Matta, J.M.;  Anterior Approach for Total Hip Replacement:  Background and Operative Technique;  Chapter 8 pp121-140 in MIS Techniques in Orthopedics (Scuderi, G.R., Tria, A.J., Berger, R.A. editors);  copyright Springer Science+Business Media, Inc.

Matta, J.M.; Ferguson, T.A.: The Anterior Approach for Hip Replacement. Orthopedics, vol 28, no. 9; p. 927-928, September 2005.

Yerasimides, J.G.; Matta, J.M.: Primary Total Hip Arthroplasty with a Minimally Invasive Anterior Approach.  Seminars in Arthroplasty, vol 16, no.3, p. 186-190, September 2005.

Matta, J.M.; Shahrdar, C.; Ferguson, T.: Single-Incision Anterior Approach for Total Hip Arthroplasty on an Orthopaedic Table.  Clin Orthop Rel Res, no. 441, p 115-124, December 2005.

Siguier, T.; Siguier, M.; Brumpt, B.: Mini-incision Anterior Approach does not increase dislocation rate. A study of 1037 Total Hip Replacements. Clin Orthop Rel Res, no. 426, p 164-171, 2004.

Anterior THA References