Round Tables

Surgeons discuss advantages, downsides of direct anterior total hip arthroplasty

Total hip arthroplasty with the direct anterior approach has gained in popularity, and residents and fellows are increasingly exposed to this technique during training.

The approach is similar to the two-incision minimally invasive surgery (MIS) total hip replacement method, which was never widely adopted by surgeons. In contrast, direct anterior total hip arthroplasty (THA) is performed by many surgeons today, without or without an orthopedic table or intraoperative fluoroscopy. In direct anterior THA, in contrast to two-incision THA, only one incision placed in the anterior thigh and it suffices for both femoral and acetabular preparation and implant insertion. In the hands of experienced surgeons, visualization and exposure of the socket and femur are at least as good as any other surgical approach for THA.

Industry seminars, surgeon-to-surgeon mentorships, and online discussions among interested surgeons have driven the popularity and adoption of this surgical technique, especially among experienced professionals who were already adept at THA with other methods, and who sought improved outcomes and more efficient surgery for their THA patients. While scientific data testifying to the safety and efficacy of direct anterior THA may be sparse, there is little doubt that patients and surgeons find value in this method.

The established scientific community may be beginning to take notice. From habitual breast-beating about the complications and risks of direct anterior THA to solemn displeasure about consumer marketing of this technique, the podium regulars at professional meetings are finally moving toward a belated acknowledgement that direct anterior THA is here to stay, and that private, practicing orthopedic surgeons brought the technique to the mainstream. What follows are the perspectives of several surgeons who routinely perform direct anterior THA. We hope the comments provide valuable insights to anyone desiring to learn more about this alternative approach to THA.

B. Sonny Bal, MD, JD, MBA
Moderator

Roundtable Participants

  • Moderator

  • B. Sonny Bal, MD, JD, MBA
  • Columbia, Mo.
  • Michael H. Bourne, MD
  • Salt Lake City
  • Gary W. Bradley, MD
  • Santa Barbara, Calif.
  • Anthony T. Carter, MD, FAAOS
  • Newport News, Va.
  • Brett D. Crist, MD, FACS
  • Columbia, Mo.
  • Philip J. Kregor, MD
  • Nashville, Tenn.
  • Gregory M. Martin, MD
  • Boynton Beach, Fla.

B. Sonny Bal, MD, JD, MBA: When did you start performing THA using the direct anterior (DA) approach? How often do you use this method for routine THA? What do you see as the major advantages of DA THA vs. other methods?

Philip J. Kregor, MD: I have used the anterior approach in all primary THAs since 2002, including those with previous proximal femoral hardware, significant obesity or proximal femoral deformity. I use a posterior approach in the few hips with previous acetabular fracture and retained posterior hardware.

My patients and I have been equally impressed with the significant advantages of anterior hip arthroplasty. Return to function is quick; average hospital stay is overnight only with walker use for 2 days to 3 days, and pain medications for 1 week to 2 weeks only. Patients return to work and activities of living sooner. Other advantages include increased accuracy in component positioning, leg length restoration and no need for hip precautions after surgery.

I also use the anterior approach for hip hemiarthroplasty or THA in the geriatric patient with a displaced femoral neck fracture. The method is advantageous since it entails less surgical trauma than other techniques. In more than 150 anterior hip arthroplasties in femoral neck fracture patients, return to function and ambulation has been faster, although this point needs to be validated in clinical trials.

Michael H. Bourne, MD: I began using the DA approach for THA 7 years ago, initially for the easy cases. Those patients did so well that I now use the DA approach in 98% of my primary THA cases. Some obese patients with tense abdominal fat make it hard, even with a fracture table, and in those cases, I use the posterior approach. Advantages of DA THA became quickly apparent to me, as patients had less pain and showed more confidence with their new hip. If a patient has had a contralateral THA using a posterior or anterolateral approach, it is a safe bet that the patient will overwhelmingly prefer the THA done with the anterior approach.

Anthony T. Carter, MD, FAAOS: After learning the method in March 2006, I have done more than 3,000 DA THAs to date, including more than 200 revisions and 350 simultaneous bilateral THAs. I have not used any other approach for primary THA during the last 4 years. There is conclusive data regarding the accelerated recovery of these patients and my average length of stay is 1.3 days. The patients have less pain and require less support, including pain medication and physical therapy. The ease of recovery in the patients is noticeable, and patients are happier with no hip precautions after surgery.

This approach has made me a better surgeon in terms of optimizing implant positioning, restoring leg length, offset and normal anatomic relationships, with better functional outcomes and happier patients. There is great comfort in knowing the position of the components, on fluoroscopy images, before leaving the operating room.

Gregory M. Martin, MD: I have performed anterior approach THA for approximately 4 years and use this technique for about 95% of my primary THAs. The advantages for the surgeon are that the most important aspects of THA are easily achievable with anterior approach surgery. Obtaining optimal cup position and reproducing leg length and offset have now become possible without significant outliers. The ability to use fluoroscopy and make changes in real-time makes sense, much more so than putting in a hip and getting an X-ray in the recovery room when you cannot change anything.

For the patient, the muscle-sparing approach facilitates quicker recovery. With any technique, some patients are “stars.” With anterior approach THA most patients are “stars.”

Gary W. Bradley, MD: I started using the anterior approach in March 2003. I use the anterior approach for all THAs and related procedures, including revisions. I believe it is a less invasive, less tissue-damaging approach that contributes to less pain and an easier recovery. An orthopedic table with the patient supine makes it a more controlled and reproducible procedure. C-arm use provides intraoperative feedback contributing to a better operation. It is extensile (once the surgeon masters the technical details) and can be used in all hip replacement surgeries and for all patients regardless of body habitus — at least to the same extent as other approaches.

My personal experience includes more than 1,000 primaries, plus femoral neck fractures, and revision cases. I have kept a database, but advantages relative to other methods will be difficult to prove as other approaches also have become more minimal and postoperative pain management has evolved.

Brett D. Crist, MD, FACS: I am a relative newcomer to this technique, although I am familiar with the anterior approach to the hip joint being a pelvic trauma surgeon. My first DA THA was in the fall of 2010. I now use this method for more than 95% of primary total hips. The rest of the time we use the posterior approach for the occasional hip hemiarthroplasty for hip fractures. The major advantages are no postoperative hip precautions and patients have been recovering faster, which includes less postoperative pain medication, less time using an assistive device and faster return to a normal gait with a decreased risk of instability. Improved patient recovery and experience is the biggest driver of this method, in my practice.

Bal: How should knowledge of anterior THA be disseminated among surgeons?

Kregor: Our knowledge of anterior hip anatomy and associated tips and pearls related to anterior THA has advanced considerably in the past 10 years. Knowledge of DA THA is disseminated by courses, cadaver workshops and surgeon visitation programs. These methods of learning seem to be effective, as more surgeons seem to be mastering the technique. The ideal learning situation is a surgeon going to a course, with a cadaver workshop, followed by a 1-day to 2-day visit to an experienced surgeon. These opportunities are readily available. In addition, an experienced surgeon working with a novice surgeon for the first few cases can be valuable, although this may be hard to accomplish in our regulatory environment.

There are online forums of surgeons who discuss anterior total hip surgery, and it is useful to have other, experienced surgeons constructively critique and discuss your postoperative radiographs.

Bourne: Teachings of DA THA is ideally disseminated through academic centers, many of which were reluctant to embrace the method. Therefore, most surgeons have learned DA THA through implant companies and seminars where knowledge can be freely exchanged. Some papers and posters are surfacing at national meetings, acknowledging this technique. Since most practicing surgeons did not learn this method in residency, a good deal of self-motivation is needed to gain proficiency. Generally, cadaver sessions followed by live surgery observation constitutes early learning for an experienced surgeon.

Carter: At present, most teaching venues for anterior THA are supported by implant vendors and their teaching curriculum varies considerably. Surgeons interested in the approach should attend one or two courses, and visit an experienced surgeon. Many companies offer regional labs for a more intimate learning experience, including cadaveric dissection. It is helpful to develop a relationship with a surgeon mentor during learning so information can be exchanged by email or telephone. There are several anterior hip user websites where a collaboration of ideas can be shared regarding a specific case or questions can be addressed to a large number of experienced master surgeons.

Martin: Unfortunately, one of the major limiting factors of DA THA is a steep learning curve. The supine position can throw off many surgeons, and bony landmarks are different than those in other total hip approaches. Because of this, surgeon education is critical. I recommend surgeon visitations and cadaver surgery prior to implementing DA THA into one’s surgical practice.

Bradley: DA THA should be taught cautiously and conservatively. Ideally, such teaching should be through peer-reviewed forums and interactive venues such as orthopedic grand rounds. It probably should not be disseminated by vendor marketing and especially not through direct-to-consumer advertising that creates unrealistic expectations for patients and undue pressure on surgeons.

Crist: In my opinion, the most effective method is to attend cadaveric instructional courses and spend time observing someone who does them routinely. This not only gets you familiar with the exposure, but it also allows you to see how people avoid or handle potential intraoperative challenges. Learning how to stay out of trouble in the first place – and how to get out of trouble – are key learning points in any operation, and DA THA is no different in that regard.

Bal: What are the major downsides, if any, of the DA approach for THA?

Kregor: Lateral thigh numbness is a known complication of anterior THA, although the technique has been refined to protect the small branches that come off laterally from the femoral cutaneous nerve. Thigh numbness does not affect function, and occurs in about one in three patients. Symptoms are minimal to non-existent 1 year after surgery.

Another concern is fracture of the greater trochanter. This can occur if the surgeon does not adequately release the soft tissues for elevation of the femur into the wound. I believe the incidence of this problem has decreased in the past 5 years through a better understanding and education regarding femoral preparation.

Bourne: The major downside of the DA approach is simply the learning curve. Some anxiety is to be expected since this learning is different from what most of us learned during residency. The best antidote for this anxiety is to attend industry seminars, use cadaver dissection, observe experienced mentors, and if necessary, have a mentor present for the first few cases at your institution.

Carter: The major downside to the approach is gaining experience in a responsible fashion. It is unreasonable to think that after attending a 1-day cadaver course one could be facile with any surgical approach for THA that routinely requires a residency and/or fellowship to be considered competently trained. The learning curve is steep, but with proper patient selection early on and following a stepwise progression of releases with diligence, nearly all hip arthritis patients can be suitable candidates for DA THA.

Martin: In my opinion, DA approach THA has few downsides. The learning curve would be the biggest downside. It can be challenging, but once it is overcome, operating time is less than for other approaches, with greater surgical accuracy. We may see more anterior hip/flexor pain than with other approaches, but all hip approaches have their limitations. It is important to reproduce limb length and femoral offset with anterior THA; since the iliotibial band is not violated, patients are more sensitive to any lengthening of the leg and increases in femoral offset. Patients may notice a bit more numbness around the incision, although none seem to care much, and it diminishes with time.

Bradley: The fact that surgeon ability to perform DA THA has become a marketing tool is a major downside. Otherwise competent and skilled surgeons may be compelled to try DA THA. The approach is different from more commonly used approaches for THA. The anatomy is viewed from an entirely different perspective; femoral shaft exposure is more difficult and, arguably, less complete. Dealing with the table is labor-intensive and somewhat daunting for the non-scrubbed OR staff. There is a complex learning curve associated with the anterior approach. It is questionable whether the net clinical benefit of switching to the anterior THA from an approach producing excellent results is justified for all surgeons.

Crist: The only downside is increased blood loss, at least in the early learning curve, when the importance of pre-emptive blood control is being understood by the surgeon. Knowledge of vessels and pre-emptive treatment with hemostasis is critical to keeping a dry operative field and this comes with experience. Two potential downsides are the dependence upon a special OR table and fluoroscopy. However, you can perform the surgery without a special table and the amount of fluoroscopy is minimal.

Bal: What are the present limitations and possible future developments in revision total hip surgery using the DA approach?  

Kregor: The advantages of the approach for a primary case apply to a revision case, perhaps more so. The advantages of minimizing dislocation, consistently accurate placement of the components, and early functional recovery are important to the revision hip patient. The limitations center around better exposure and access to the femur for longer reamers, broaches, and stems which may be desired in revision cases. Access to the acetabular component is relatively straight forward, such that bearing exchange can be done easily. A 1 cm to 3 cm release of the tensor fascia muscle greatly facilitates femoral exposure, as does an osteotomy of the anterior superior iliac spine. Both can be done with minimal functional concerns for the patient. Still, revision femoral exposure can be challenging. We will undoubtedly learn more tricks for revision DA total hip surgery over the next few years.

Bourne: The DA approach is suitable for excellent acetabular exposure, such that revision of cups or liner exchanges is relatively straightforward, with quick recovery. If the femoral stem is loose, it is a fairly easy approach to remove the stem or revise both acetabular and femoral sides. In cases of a well-fixed femoral component where a femoral osteotomy is needed, I would move away from the anterior approach for revision surgery.

Carter: The approach is extensile both proximally and distally, and I use the approach for all revisions at this time except if there is a posterior wall/column defect of the acetabulum or posterior wall hardware that will require removal. There are a growing number of surgeons expanding the indications for revision surgery with this approach. Cup revisions are rather straight-forward with this approach, and revisions of loose and even well-fixed stems can be performed with or without additional osteotomies, such as an iliac crest osteotomy, an extended trochanteric osteotomy or a longitudinal split along the calcar for femoral stem removal.

Martin: Many types of revision surgery are possible with a DA hip approach. The visualization of the cup is excellent and, with the exception of major posterior wall deficiencies, most acetabular revisions can be safely performed. The femoral revisions potentially can be more difficult. However, exposure looking down the canal (e.g., cement removal or getting around an ingrown stem with osteotomes) can be excellent. As surgical techniques and instrumentation evolve, I predict we will see more revisions performed with the DA method.

Bradley: Nothing about surgery is easy, despite comments to the contrary delivered commonly from the podium at professional meetings. Judet’s anterior surgical approach gives excellent exposure to the acetabulum, but femoral exposure is difficult. Kristaps J. Keggi, MD, has written extensively about revision surgery using the anterior approach. Femoral exposure, especially for osteotomy during revision surgery, is more difficult but can be achieved. Proximal femoral access is also more difficult — but not prohibitively so — than for other approaches. On the other hand, C-arm use is much facilitated so obtaining access to intra-canal cement can be guided and in some cases, the need for femoral osteotomy can be obviated. Recovery from revision THA using the DA approach closely resembles that from a primary procedure with regard to pain and muscle control.

Crist: The only potential limitation is if pelvic discontinuity needs to be addressed during the revision surgery. It would be difficult to plate the posterior column even using the extensile nature of the Hueter approach, upon which DA THA is derived. If needed, you can convert it to a standard or extensile iliofemoral approach. By extending the surgical exposure, using the iliofemoral intervals, you can access the entire femur and acetabulum. But, it would be difficult to plate the posterior column in the supine position. Mast and colleagues showed that revision arthroplasty can be performed using this approach.

Bal: Where do you see the future role of the DA THA, specifically in teaching a new generation of surgeons? Is DA THA a passing fad or a new standard technique in performing THA?

Kregor: It certainly is not a fad. There needs to be further proof of its advantages, particularly in the early months in terms of functional recovery. Emerging data is slowly establishing the benefit of the anterior approach. As with all newer surgical approaches, I believe residents should be exposed to the anterior THA in training program, and become facile with its use. All new techniques take time, and then become an established standard. All new things also provoke a measure of discomfort.

Bourne: The DA THA is a passing fad. The intraoperative treatment of the muscles allows for a rapid recovery without requiring postoperative dislocation precautions. The use of a special table and X-ray confirmation of component position allows precise placement of the acetabular cup, which also helps in stability. Furthermore, radiographic confirmation directly at the time of surgery can ensure accurate limb length and offset.

Once learned, this approach is less stressful on the surgeon and the assistant, and is precise. I believe the anterior approach is here to stay as evidenced by its surgical advantages, patient preference and growing popularity.

Carter: There is enough data and a continued interest in the approach that it is not a passing fad. Several surgeons, including community surgeons like myself, have embraced the approach and benefited from the improved patient results with increased volume and referral base. In my region, DA THA is the standard of care. As more residency and fellowship programs catch up, the next generation of surgeons and patients will continue to drive demand for DA THA. In modern health care, any procedure that can accelerate recovery and decrease demand for perioperative services should be encouraged. It is the responsibility of teaching programs to expose residents to the procedure and let them decide for themselves if it is worth pursuing.

Martin: The role of anterior approach THA will continue to grow, and this method is far from a passing fad. The demand, primarily from patients, is tremendous. As more surgeons get their residency training with surgeons using the technique, it will be adapted more readily than having older surgeons convert, or criticize it from the sidelines. The technique has already been used in the United State for more than 10 years and continues to experience strong growth.

Bradley: The evolution of the technique will probably parallel the experience with other surgical approaches. I see an increase in the incidence of DA THA as more residents learn this method and as seminars continue to disseminate knowledge. I do not see it as completely displacing any other approach or being done nearly as often as the posterior approach, at least not in the near future.

Crist: The DA approach should be viewed as a relevant and effective approach for the next generation of orthopedic surgeons. All trainees should gain exposure to this technique. Even if they do not perform arthroplasties through the exposure, they can become comfortable doing the exposure for open reduction of femoral neck fractures. I think it is a new standard. The surgical approach has been around longer than the Kocher approach. It has just become more popular of late because people have disseminated that they feel they have better results.

I also believe this technique will make THA a routine procedure for orthopaedic trauma surgeons who are trained in this method. As the number of elderly patients with femoral neck fractures continues to increase and the evidence of improved outcomes for total hips in active seniors for this problem continues to be reported, the ability to do a DA total hip is appealing for me as a trauma surgeon. It has the same surgical exposure I use for open reduction of femoral neck fractures and open hip preservation procedures like femoral head osteoplasty. I also perform hemiarthroplasties through the DA approach for the same reasons I do for THA. We are hoping to show that the benefits of the DA approach seen in THA also apply to hip hemiarthroplasty. Therefore, it is a useful surgical exposure and technique for surgeons that manage a wide variety of hip problems.

References:
Kaspar S. J Arthrop. 2003. doi:10.1054/arth.2003.50028.
Kennon R. J Bone Joint Surg Am. 2004;86 Suppl 2:91-97.
Mast NH. J Bone Joint Surg Am. 2011. doi:10.2106/JBJS.J.01736.
For more information:
B. Sonny Bal, MD, JD, MBA, can be reached at University of Missouri School of Medicine, Department of Orthopaedic Surgery, One Hospital Drive, Columbia, MO 65201; email: balb@health.missouri.edu.
Michael H. Bourne, MD, can be reached at St. Mark’s Hospital, Salt Lake Orthopaedic Clinic, Division of Orthopaedic Surgery, 1200 E. 3900 S., Salt Lake City, UT 84124; email: mhbourne@msn.com.
Gary W. Bradley, MD, can be reached at Alta Orthopaedics, 511 Bath St., Santa Barbara, CA 93101; email: gwb@altaortho.com.
Anthony T. Carter, MD, FAAOS, can be reached at Mary Immaculate Hospital, Hampton Roads Orthopaedics & Sports Medicine, 2 Bernardine Dr., Newport News, VA 23602; email: orthoace2@aol.com.
Brett D. Crist, MD, FACS, can be reached at Department of Orthopaedic Surgery, University of Missouri, One Hospital Dr., Columbia, MO 65201; email: cristb@health.missouri.edu.
Philip J. Kregor, MD, can be reached at Hip and Fracture Institute – Nashville, 345 23rd Ave. North. Suite 301, Nashville, TN 37203; email: philip.kregor@hipandfracture.com.
Gregory M. Martin, MD, can be reached at Orthopedic Institute, JFK Medical Center, 5301 South Congress Ave., Atlantis, FL 33462; email: gm277@yahoo.com.
Disclosures: Bal, Crist and Martin have no relevant financial disclosures; Bourne is a speaker for DePuy and Ortho Development and receives royalties and has stock ownership in Ortho Development; Bradley is a consultant for Medacta, receives royalties from Innomed and has a committee appointment with the AAOS; Carter is a consultant for DePuy/Synthes, Smith & Nephew and Medtronic; Kregor receives honoraria from Medtronic to speak on anterior total hip arthroplasty.

Total hip arthroplasty with the direct anterior approach has gained in popularity, and residents and fellows are increasingly exposed to this technique during training.

The approach is similar to the two-incision minimally invasive surgery (MIS) total hip replacement method, which was never widely adopted by surgeons. In contrast, direct anterior total hip arthroplasty (THA) is performed by many surgeons today, without or without an orthopedic table or intraoperative fluoroscopy. In direct anterior THA, in contrast to two-incision THA, only one incision placed in the anterior thigh and it suffices for both femoral and acetabular preparation and implant insertion. In the hands of experienced surgeons, visualization and exposure of the socket and femur are at least as good as any other surgical approach for THA.

Industry seminars, surgeon-to-surgeon mentorships, and online discussions among interested surgeons have driven the popularity and adoption of this surgical technique, especially among experienced professionals who were already adept at THA with other methods, and who sought improved outcomes and more efficient surgery for their THA patients. While scientific data testifying to the safety and efficacy of direct anterior THA may be sparse, there is little doubt that patients and surgeons find value in this method.

The established scientific community may be beginning to take notice. From habitual breast-beating about the complications and risks of direct anterior THA to solemn displeasure about consumer marketing of this technique, the podium regulars at professional meetings are finally moving toward a belated acknowledgement that direct anterior THA is here to stay, and that private, practicing orthopedic surgeons brought the technique to the mainstream. What follows are the perspectives of several surgeons who routinely perform direct anterior THA. We hope the comments provide valuable insights to anyone desiring to learn more about this alternative approach to THA.

B. Sonny Bal, MD, JD, MBA
Moderator

Roundtable Participants

  • Moderator

  • B. Sonny Bal, MD, JD, MBA
  • Columbia, Mo.
  • Michael H. Bourne, MD
  • Salt Lake City
  • Gary W. Bradley, MD
  • Santa Barbara, Calif.
  • Anthony T. Carter, MD, FAAOS
  • Newport News, Va.
  • Brett D. Crist, MD, FACS
  • Columbia, Mo.
  • Philip J. Kregor, MD
  • Nashville, Tenn.
  • Gregory M. Martin, MD
  • Boynton Beach, Fla.

B. Sonny Bal, MD, JD, MBA: When did you start performing THA using the direct anterior (DA) approach? How often do you use this method for routine THA? What do you see as the major advantages of DA THA vs. other methods?

Philip J. Kregor, MD: I have used the anterior approach in all primary THAs since 2002, including those with previous proximal femoral hardware, significant obesity or proximal femoral deformity. I use a posterior approach in the few hips with previous acetabular fracture and retained posterior hardware.

My patients and I have been equally impressed with the significant advantages of anterior hip arthroplasty. Return to function is quick; average hospital stay is overnight only with walker use for 2 days to 3 days, and pain medications for 1 week to 2 weeks only. Patients return to work and activities of living sooner. Other advantages include increased accuracy in component positioning, leg length restoration and no need for hip precautions after surgery.

I also use the anterior approach for hip hemiarthroplasty or THA in the geriatric patient with a displaced femoral neck fracture. The method is advantageous since it entails less surgical trauma than other techniques. In more than 150 anterior hip arthroplasties in femoral neck fracture patients, return to function and ambulation has been faster, although this point needs to be validated in clinical trials.

Michael H. Bourne, MD: I began using the DA approach for THA 7 years ago, initially for the easy cases. Those patients did so well that I now use the DA approach in 98% of my primary THA cases. Some obese patients with tense abdominal fat make it hard, even with a fracture table, and in those cases, I use the posterior approach. Advantages of DA THA became quickly apparent to me, as patients had less pain and showed more confidence with their new hip. If a patient has had a contralateral THA using a posterior or anterolateral approach, it is a safe bet that the patient will overwhelmingly prefer the THA done with the anterior approach.

PAGE BREAK

Anthony T. Carter, MD, FAAOS: After learning the method in March 2006, I have done more than 3,000 DA THAs to date, including more than 200 revisions and 350 simultaneous bilateral THAs. I have not used any other approach for primary THA during the last 4 years. There is conclusive data regarding the accelerated recovery of these patients and my average length of stay is 1.3 days. The patients have less pain and require less support, including pain medication and physical therapy. The ease of recovery in the patients is noticeable, and patients are happier with no hip precautions after surgery.

This approach has made me a better surgeon in terms of optimizing implant positioning, restoring leg length, offset and normal anatomic relationships, with better functional outcomes and happier patients. There is great comfort in knowing the position of the components, on fluoroscopy images, before leaving the operating room.

Gregory M. Martin, MD: I have performed anterior approach THA for approximately 4 years and use this technique for about 95% of my primary THAs. The advantages for the surgeon are that the most important aspects of THA are easily achievable with anterior approach surgery. Obtaining optimal cup position and reproducing leg length and offset have now become possible without significant outliers. The ability to use fluoroscopy and make changes in real-time makes sense, much more so than putting in a hip and getting an X-ray in the recovery room when you cannot change anything.

For the patient, the muscle-sparing approach facilitates quicker recovery. With any technique, some patients are “stars.” With anterior approach THA most patients are “stars.”

Gary W. Bradley, MD: I started using the anterior approach in March 2003. I use the anterior approach for all THAs and related procedures, including revisions. I believe it is a less invasive, less tissue-damaging approach that contributes to less pain and an easier recovery. An orthopedic table with the patient supine makes it a more controlled and reproducible procedure. C-arm use provides intraoperative feedback contributing to a better operation. It is extensile (once the surgeon masters the technical details) and can be used in all hip replacement surgeries and for all patients regardless of body habitus — at least to the same extent as other approaches.

My personal experience includes more than 1,000 primaries, plus femoral neck fractures, and revision cases. I have kept a database, but advantages relative to other methods will be difficult to prove as other approaches also have become more minimal and postoperative pain management has evolved.

Brett D. Crist, MD, FACS: I am a relative newcomer to this technique, although I am familiar with the anterior approach to the hip joint being a pelvic trauma surgeon. My first DA THA was in the fall of 2010. I now use this method for more than 95% of primary total hips. The rest of the time we use the posterior approach for the occasional hip hemiarthroplasty for hip fractures. The major advantages are no postoperative hip precautions and patients have been recovering faster, which includes less postoperative pain medication, less time using an assistive device and faster return to a normal gait with a decreased risk of instability. Improved patient recovery and experience is the biggest driver of this method, in my practice.

Bal: How should knowledge of anterior THA be disseminated among surgeons?

Kregor: Our knowledge of anterior hip anatomy and associated tips and pearls related to anterior THA has advanced considerably in the past 10 years. Knowledge of DA THA is disseminated by courses, cadaver workshops and surgeon visitation programs. These methods of learning seem to be effective, as more surgeons seem to be mastering the technique. The ideal learning situation is a surgeon going to a course, with a cadaver workshop, followed by a 1-day to 2-day visit to an experienced surgeon. These opportunities are readily available. In addition, an experienced surgeon working with a novice surgeon for the first few cases can be valuable, although this may be hard to accomplish in our regulatory environment.

PAGE BREAK

There are online forums of surgeons who discuss anterior total hip surgery, and it is useful to have other, experienced surgeons constructively critique and discuss your postoperative radiographs.

Bourne: Teachings of DA THA is ideally disseminated through academic centers, many of which were reluctant to embrace the method. Therefore, most surgeons have learned DA THA through implant companies and seminars where knowledge can be freely exchanged. Some papers and posters are surfacing at national meetings, acknowledging this technique. Since most practicing surgeons did not learn this method in residency, a good deal of self-motivation is needed to gain proficiency. Generally, cadaver sessions followed by live surgery observation constitutes early learning for an experienced surgeon.

Carter: At present, most teaching venues for anterior THA are supported by implant vendors and their teaching curriculum varies considerably. Surgeons interested in the approach should attend one or two courses, and visit an experienced surgeon. Many companies offer regional labs for a more intimate learning experience, including cadaveric dissection. It is helpful to develop a relationship with a surgeon mentor during learning so information can be exchanged by email or telephone. There are several anterior hip user websites where a collaboration of ideas can be shared regarding a specific case or questions can be addressed to a large number of experienced master surgeons.

Martin: Unfortunately, one of the major limiting factors of DA THA is a steep learning curve. The supine position can throw off many surgeons, and bony landmarks are different than those in other total hip approaches. Because of this, surgeon education is critical. I recommend surgeon visitations and cadaver surgery prior to implementing DA THA into one’s surgical practice.

Bradley: DA THA should be taught cautiously and conservatively. Ideally, such teaching should be through peer-reviewed forums and interactive venues such as orthopedic grand rounds. It probably should not be disseminated by vendor marketing and especially not through direct-to-consumer advertising that creates unrealistic expectations for patients and undue pressure on surgeons.

Crist: In my opinion, the most effective method is to attend cadaveric instructional courses and spend time observing someone who does them routinely. This not only gets you familiar with the exposure, but it also allows you to see how people avoid or handle potential intraoperative challenges. Learning how to stay out of trouble in the first place – and how to get out of trouble – are key learning points in any operation, and DA THA is no different in that regard.

Bal: What are the major downsides, if any, of the DA approach for THA?

Kregor: Lateral thigh numbness is a known complication of anterior THA, although the technique has been refined to protect the small branches that come off laterally from the femoral cutaneous nerve. Thigh numbness does not affect function, and occurs in about one in three patients. Symptoms are minimal to non-existent 1 year after surgery.

Another concern is fracture of the greater trochanter. This can occur if the surgeon does not adequately release the soft tissues for elevation of the femur into the wound. I believe the incidence of this problem has decreased in the past 5 years through a better understanding and education regarding femoral preparation.

Bourne: The major downside of the DA approach is simply the learning curve. Some anxiety is to be expected since this learning is different from what most of us learned during residency. The best antidote for this anxiety is to attend industry seminars, use cadaver dissection, observe experienced mentors, and if necessary, have a mentor present for the first few cases at your institution.

Carter: The major downside to the approach is gaining experience in a responsible fashion. It is unreasonable to think that after attending a 1-day cadaver course one could be facile with any surgical approach for THA that routinely requires a residency and/or fellowship to be considered competently trained. The learning curve is steep, but with proper patient selection early on and following a stepwise progression of releases with diligence, nearly all hip arthritis patients can be suitable candidates for DA THA.

PAGE BREAK

Martin: In my opinion, DA approach THA has few downsides. The learning curve would be the biggest downside. It can be challenging, but once it is overcome, operating time is less than for other approaches, with greater surgical accuracy. We may see more anterior hip/flexor pain than with other approaches, but all hip approaches have their limitations. It is important to reproduce limb length and femoral offset with anterior THA; since the iliotibial band is not violated, patients are more sensitive to any lengthening of the leg and increases in femoral offset. Patients may notice a bit more numbness around the incision, although none seem to care much, and it diminishes with time.

Bradley: The fact that surgeon ability to perform DA THA has become a marketing tool is a major downside. Otherwise competent and skilled surgeons may be compelled to try DA THA. The approach is different from more commonly used approaches for THA. The anatomy is viewed from an entirely different perspective; femoral shaft exposure is more difficult and, arguably, less complete. Dealing with the table is labor-intensive and somewhat daunting for the non-scrubbed OR staff. There is a complex learning curve associated with the anterior approach. It is questionable whether the net clinical benefit of switching to the anterior THA from an approach producing excellent results is justified for all surgeons.

Crist: The only downside is increased blood loss, at least in the early learning curve, when the importance of pre-emptive blood control is being understood by the surgeon. Knowledge of vessels and pre-emptive treatment with hemostasis is critical to keeping a dry operative field and this comes with experience. Two potential downsides are the dependence upon a special OR table and fluoroscopy. However, you can perform the surgery without a special table and the amount of fluoroscopy is minimal.

Bal: What are the present limitations and possible future developments in revision total hip surgery using the DA approach?  

Kregor: The advantages of the approach for a primary case apply to a revision case, perhaps more so. The advantages of minimizing dislocation, consistently accurate placement of the components, and early functional recovery are important to the revision hip patient. The limitations center around better exposure and access to the femur for longer reamers, broaches, and stems which may be desired in revision cases. Access to the acetabular component is relatively straight forward, such that bearing exchange can be done easily. A 1 cm to 3 cm release of the tensor fascia muscle greatly facilitates femoral exposure, as does an osteotomy of the anterior superior iliac spine. Both can be done with minimal functional concerns for the patient. Still, revision femoral exposure can be challenging. We will undoubtedly learn more tricks for revision DA total hip surgery over the next few years.

Bourne: The DA approach is suitable for excellent acetabular exposure, such that revision of cups or liner exchanges is relatively straightforward, with quick recovery. If the femoral stem is loose, it is a fairly easy approach to remove the stem or revise both acetabular and femoral sides. In cases of a well-fixed femoral component where a femoral osteotomy is needed, I would move away from the anterior approach for revision surgery.

Carter: The approach is extensile both proximally and distally, and I use the approach for all revisions at this time except if there is a posterior wall/column defect of the acetabulum or posterior wall hardware that will require removal. There are a growing number of surgeons expanding the indications for revision surgery with this approach. Cup revisions are rather straight-forward with this approach, and revisions of loose and even well-fixed stems can be performed with or without additional osteotomies, such as an iliac crest osteotomy, an extended trochanteric osteotomy or a longitudinal split along the calcar for femoral stem removal.

PAGE BREAK

Martin: Many types of revision surgery are possible with a DA hip approach. The visualization of the cup is excellent and, with the exception of major posterior wall deficiencies, most acetabular revisions can be safely performed. The femoral revisions potentially can be more difficult. However, exposure looking down the canal (e.g., cement removal or getting around an ingrown stem with osteotomes) can be excellent. As surgical techniques and instrumentation evolve, I predict we will see more revisions performed with the DA method.

Bradley: Nothing about surgery is easy, despite comments to the contrary delivered commonly from the podium at professional meetings. Judet’s anterior surgical approach gives excellent exposure to the acetabulum, but femoral exposure is difficult. Kristaps J. Keggi, MD, has written extensively about revision surgery using the anterior approach. Femoral exposure, especially for osteotomy during revision surgery, is more difficult but can be achieved. Proximal femoral access is also more difficult — but not prohibitively so — than for other approaches. On the other hand, C-arm use is much facilitated so obtaining access to intra-canal cement can be guided and in some cases, the need for femoral osteotomy can be obviated. Recovery from revision THA using the DA approach closely resembles that from a primary procedure with regard to pain and muscle control.

Crist: The only potential limitation is if pelvic discontinuity needs to be addressed during the revision surgery. It would be difficult to plate the posterior column even using the extensile nature of the Hueter approach, upon which DA THA is derived. If needed, you can convert it to a standard or extensile iliofemoral approach. By extending the surgical exposure, using the iliofemoral intervals, you can access the entire femur and acetabulum. But, it would be difficult to plate the posterior column in the supine position. Mast and colleagues showed that revision arthroplasty can be performed using this approach.

Bal: Where do you see the future role of the DA THA, specifically in teaching a new generation of surgeons? Is DA THA a passing fad or a new standard technique in performing THA?

Kregor: It certainly is not a fad. There needs to be further proof of its advantages, particularly in the early months in terms of functional recovery. Emerging data is slowly establishing the benefit of the anterior approach. As with all newer surgical approaches, I believe residents should be exposed to the anterior THA in training program, and become facile with its use. All new techniques take time, and then become an established standard. All new things also provoke a measure of discomfort.

Bourne: The DA THA is a passing fad. The intraoperative treatment of the muscles allows for a rapid recovery without requiring postoperative dislocation precautions. The use of a special table and X-ray confirmation of component position allows precise placement of the acetabular cup, which also helps in stability. Furthermore, radiographic confirmation directly at the time of surgery can ensure accurate limb length and offset.

Once learned, this approach is less stressful on the surgeon and the assistant, and is precise. I believe the anterior approach is here to stay as evidenced by its surgical advantages, patient preference and growing popularity.

Carter: There is enough data and a continued interest in the approach that it is not a passing fad. Several surgeons, including community surgeons like myself, have embraced the approach and benefited from the improved patient results with increased volume and referral base. In my region, DA THA is the standard of care. As more residency and fellowship programs catch up, the next generation of surgeons and patients will continue to drive demand for DA THA. In modern health care, any procedure that can accelerate recovery and decrease demand for perioperative services should be encouraged. It is the responsibility of teaching programs to expose residents to the procedure and let them decide for themselves if it is worth pursuing.

PAGE BREAK

Martin: The role of anterior approach THA will continue to grow, and this method is far from a passing fad. The demand, primarily from patients, is tremendous. As more surgeons get their residency training with surgeons using the technique, it will be adapted more readily than having older surgeons convert, or criticize it from the sidelines. The technique has already been used in the United State for more than 10 years and continues to experience strong growth.

Bradley: The evolution of the technique will probably parallel the experience with other surgical approaches. I see an increase in the incidence of DA THA as more residents learn this method and as seminars continue to disseminate knowledge. I do not see it as completely displacing any other approach or being done nearly as often as the posterior approach, at least not in the near future.

Crist: The DA approach should be viewed as a relevant and effective approach for the next generation of orthopedic surgeons. All trainees should gain exposure to this technique. Even if they do not perform arthroplasties through the exposure, they can become comfortable doing the exposure for open reduction of femoral neck fractures. I think it is a new standard. The surgical approach has been around longer than the Kocher approach. It has just become more popular of late because people have disseminated that they feel they have better results.

I also believe this technique will make THA a routine procedure for orthopaedic trauma surgeons who are trained in this method. As the number of elderly patients with femoral neck fractures continues to increase and the evidence of improved outcomes for total hips in active seniors for this problem continues to be reported, the ability to do a DA total hip is appealing for me as a trauma surgeon. It has the same surgical exposure I use for open reduction of femoral neck fractures and open hip preservation procedures like femoral head osteoplasty. I also perform hemiarthroplasties through the DA approach for the same reasons I do for THA. We are hoping to show that the benefits of the DA approach seen in THA also apply to hip hemiarthroplasty. Therefore, it is a useful surgical exposure and technique for surgeons that manage a wide variety of hip problems.

References:
Kaspar S. J Arthrop. 2003. doi:10.1054/arth.2003.50028.
Kennon R. J Bone Joint Surg Am. 2004;86 Suppl 2:91-97.
Mast NH. J Bone Joint Surg Am. 2011. doi:10.2106/JBJS.J.01736.
For more information:
B. Sonny Bal, MD, JD, MBA, can be reached at University of Missouri School of Medicine, Department of Orthopaedic Surgery, One Hospital Drive, Columbia, MO 65201; email: balb@health.missouri.edu.
Michael H. Bourne, MD, can be reached at St. Mark’s Hospital, Salt Lake Orthopaedic Clinic, Division of Orthopaedic Surgery, 1200 E. 3900 S., Salt Lake City, UT 84124; email: mhbourne@msn.com.
Gary W. Bradley, MD, can be reached at Alta Orthopaedics, 511 Bath St., Santa Barbara, CA 93101; email: gwb@altaortho.com.
Anthony T. Carter, MD, FAAOS, can be reached at Mary Immaculate Hospital, Hampton Roads Orthopaedics & Sports Medicine, 2 Bernardine Dr., Newport News, VA 23602; email: orthoace2@aol.com.
Brett D. Crist, MD, FACS, can be reached at Department of Orthopaedic Surgery, University of Missouri, One Hospital Dr., Columbia, MO 65201; email: cristb@health.missouri.edu.
Philip J. Kregor, MD, can be reached at Hip and Fracture Institute – Nashville, 345 23rd Ave. North. Suite 301, Nashville, TN 37203; email: philip.kregor@hipandfracture.com.
Gregory M. Martin, MD, can be reached at Orthopedic Institute, JFK Medical Center, 5301 South Congress Ave., Atlantis, FL 33462; email: gm277@yahoo.com.
Disclosures: Bal, Crist and Martin have no relevant financial disclosures; Bourne is a speaker for DePuy and Ortho Development and receives royalties and has stock ownership in Ortho Development; Bradley is a consultant for Medacta, receives royalties from Innomed and has a committee appointment with the AAOS; Carter is a consultant for DePuy/Synthes, Smith & Nephew and Medtronic; Kregor receives honoraria from Medtronic to speak on anterior total hip arthroplasty.