Anterior vs. Posterior Hip Replacement:

A Comparative Analysis

ANTERIOR VS. POSTERIOR HIP REPLACEMENT

In the world of orthopaedic surgery, some surgery centers and hospitals are touting the benefits of one method of hip replacement over another.  One debate between orthopaedic surgeons is whether anterior approach to the hip joint is superior to the more traditionally practiced posterior incision.

The National Center for Biotechnology Information published an online article stating, “Total hip arthroplasty through an anterior approach has been increasing in popularity amongst surgeons and patients.”

Get facts to decide between hip replacement options

However, orthopaedic surgeon Lawrence D. Dorr, medical director of the Dorr Arthritis Institute, is saying not so fast!  Dorr states in an article that it is unfair to patients when doctors or hospitals market a particular type of surgery as “better” when there is no scientific evidence to support that assertion.  He expresses the belief that false marketing is currently in use to promote the anterior approach for total hip replacement.

Here are some of the benefits listed in these marketing efforts for the anterior approach.

  • Better outcomes
  • Quicker recovery
  • No muscle cuts

Dorr writes, “It is unfair marketing because there is NO scientific data to support these claims.”

In another article, Richard A. Sweet, M.D., with Louisville Orthopaedic Clinic, wrote an exhaustive “pro and con” analysis of the posterior and anterior approaches to total hip replacement.

Analyzing the claims for hip replacement options

Dorr describes randomized studies that have used specific indications to assess the outcomes of the  posterior and anterior approaches to the hip joint.

For example, the Mayo Clinic conducted one randomized study regarding the incision size in the anterior/posterior entry debate.  That study found no difference in outcome for any criterion studied.

Study results for patients undergoing the posterior approach

Rapid recovery

The Mayo Clinic published an article about patients undergoing total hip replacements with the posterior approach who were discharged from the hospital the same day as the surgery.  The patients in this study kept diaries providing recovery information at the three-week mark after their surgery.  Dr. Dorr challenged anyone who asserted that the anterior approach resulted in a quicker recovery to provide corresponding data rather than anecdotal opinion.

Here is that data for the three-week mark collected in this study.

  • The reported pain score was 1.9. Standard pain scoring is a 1-10 scale with scores of 1-3 indicating mild discomfort and scores of 7-10 indicating severe pain.
  • 98% of patients were able to walk one mile.
  • 41% were no longer walking with a cane.
  • 87% had already returned to work.
  • 64% no longer required pain medication.
  • 84% were driving.

Gait evaluation

This test measures patients’ walking ability with muscle function.  In fact, it is considered one of the most reliable tests orthopaedic physicians use to objectively evaluate postoperative function.  In addition to tests performed at the Mayo Clinic, there were similar gait tests performed at Duke University, the University of California at Berkeley and in Canada.  There were no recorded differences in results regardless of the incision size.

Postoperative dislocation prevention

Those who favor the anterior approach assert its superiority in preventing post-operative dislocation.  However, the randomized Mayo Clinic study did not support this assertion.  The Mayo Clinic data for dislocation reports its incidence at .7%, which compares to another study reporting .6%.  Dislocation is currently much less of a complication concern than in the past.  This is the result of improved technical performance in hip replacement along with the use of larger femoral heads.

Dr. Sweet’s Pro/Con Analysis

Here is a small sampling of Dr. Sweet’s analysis of the two surgical entry methods for total hip replacements.

PosteriorAnterior
Incision size: The incision length is generally 8-10 cm long, depending upon case difficulty.Same incision size.
Risk of blood transfusion: There is less risk of needing a transfusion in surgery due to excessive blood loss. Risk of blood transfusion: There tends to be more chance of the need for a blood transfusion.
Nerve damage risk: The risk of nerve damage in an experienced surgeon’s hands is close to zero.The risk of nerve damage for this method is greater. This involves the risk of permanent damage to the Lateral Femoral Cutaneous nerve. This nerve is responsible for sensation in the thigh.
There is a low risk for femur fracture.The risk of femur fracture is greater with this method because of the difficulty with exposure. When approaching the hip joint, there is a need to pry on the bone to gain the necessary exposure. There is even more risk in patients with osteoporosis.
Risk of improper implant positioning: LowerHigher – This method requires intraoperative x-rays. Because of more difficulty in exposing the femur, the risk of improper implant positioning is another concern alongside femur fracture. Improper implant positioning can affect hip function, both short and long-term.
Hip dislocation risk: Very low risk. When dislocations occur, they are posterior. Patients can avoid this complication by not sitting on low seats. Since this risk is avoidable, there is less likelihood of disability. Very low risk here too. However, when dislocations occur, they are anterior and tend to be very disabling. This can happen when a patient externally rotates the leg when standing, walking or participating in recreational activity.
Physical therapy needs: Minimal / none.Same
Time on walker/crutches: Patients may wean off these as tolerated. Younger and more fit, motivated patients will be able to stop using the walker in a few days.Same

Infection rates for hip replacement options

One extremely important issue to consider when facing any surgery is the risk of infection.  The Boston-based Brigham and Women’s Hospital website published an article about infection rates between the direct anterior (DA) or non-anterior (NA-which is posterior) approaches to total hip replacement. According to this article, Richard Lorio, M.D conducted a study at the hospital comparing infection rates between the two approaches.

Dr. Lorio and his research assistants studied infection rates between two groups of patients undergoing total hip replacements. The DA group consisted of 1,985 patients while the NA group consisted of 4,101 patients. Researchers found an infection rate of 1.22 percent among the DA patients. On the other hand, the NA patients had an infection rate of .63 percent.  Thus, there is double the risk with the anterior approach.

The Delcore Experience

Randy Delcore, M.D. has been using the minimally invasive posterior approach for 25 years, combined with mulit-modal non-narcotic anesthesia. Consequently, this allows for patients to be ambulating within an hour of surgery completion (consistently), and transitioning to discharge on the same day within 2-3 hours.  Additionally, there has been an exceedingly low dislocation rate and zero percent infection rate since 1995.

Interpreting the data

Finally, Dorr wrote that the same outcomes are possible whether a surgeon uses the posterior or anterior method.  He wrote that patients should base their choice of a surgeon on published data (if available) and his or her reputation in the community.

He listed the following as key elements in total hip replacement.  They are the primary determinants in the comfort and longevity of your hip implant.   As such, they are in the hands of your chosen surgeon.

  • Positioning of the implants
  • The biomechanical reconstruction of the hip

Delcore adds two other determinants in the comfort and longevity of hip implants.

  • Ensuring optimal fixation to substrate (whether uncemented and machining of a bone in-growth prosthetic, or cemented and adhering to gold-standard cementing techniques).
  • Fastidious attention to “stability” of the hip prior to coming off the table.

Dr. Delcore has been replacing hips for more than 30 years and personally favors the posterior approach.  While he performs this procedure at the local hospital, he has also been performing outpatient total hip replacements at Cedar Orthopaedic Surgery Center since 2005.  He treats local patients, those from out-of-town, and even medical tourists from afar. His bundled transparent pricing offers affordable care to all.

So, do you want to learn about what you can expect from your hip replacement?  Go to our home page for videos of former patients.  Then call (435) 586-5131 to chat with our surgical staff about what we can do for you.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6275850/

http://www.dorrarthritisinstitute.org/pdf/anterior-posterior-approach-total-hip-replacement.pdf