Exploring advances in hip replacement surgery

zoom

A look at recent developments in hip replacement, including minimally invasive surgery, hip resurfacing, and new materials.

Hip replacement, or total hip arthroplasty, is one of the world's most common orthopeadic surgeries thanks to its remarkable success in relieving pain and restoring function to people with disabling osteoarthritis of the hip joint.

The procedure is often recommended for patients who suffer from severe degenerative joint disease that does not respond to conservative approaches, such as weight loss, non-steroidal anti-inflammatory drugs, or physical therapy. Other patients who may benefit from hip replacement include those with rheumatoid arthritis, hip fracture, bone tumors, and avascular necrosis of the femoral head.

More than a million joint replacements (mostly hip and knee) are performed each year worldwide and with an aging population, this number is expected to continue to grow. Many consider total hip replacement to be one of the most significant advances in orthopaedic surgery. It is also big business.

Device manufacturers are continually investing in new prosthesis designs and fabrication, bearing surfaces, and custom-made components. Meanwhile, surgeons have been exploring techniques involving smaller incisions in the hope of speeding patient recovery, minimizing pain, sparing muscle, and reducing blood loss. But how much do these new technologies and techniques really improve patient care?

In this "In Practice," Douglas K. Ayres, M.D., M.B.A., Vice Chief, Department of Orthopedic Surgery at Beth Israel Deaconess Medical Center in Boston, Massachusetts, weighs in on some of the recent developments, including minimally invasive surgery, hip resurfacing, and new materials.

The basics

In conventional total hip arthroplasty, a surgeon makes a 15 to 25 cm incision and cuts through the hip capsule and several overlying tendons to access the hip joint. The surgeon removes the head and much of the neck of the femur and replaces them with a femoral head and stem, and reams away the outer bony surface layer of the acetabulum, replacing it with an artificial socket attached to the pelvis.

Cement may be used to bond these porous metal alloy implants to the existing bone, or most often, the artificial parts may be made of a porous material that supports bone growth, which holds the parts in place.

Although many patients who undergo hip replacement surgery are between age 60 and 80, younger patients may benefit from the procedure if they suffer extreme pain, disability, and loss of function due to their injured or diseased joint.

Minimally invasive surgery (one-incision and two-incision)

Almost a decade ago, minimally invasive techniques were introduced that use specially designed instruments to insert hip prostheses through smaller incisions (usually measuring 10 cm or less in total), often using fluoroscopy. The goals of minimally invasive surgery (MIS) are to reduce soft tissue injury and blood loss, and to shorten post-op recovery, with results comparable to the excellent outcomes of conventional hip replacement.

So far, some orthopedic surgeons operating on select patients in high volume medical centers have shown results that suggest MIS can indeed lessen blood loss and provide faster rehabilitation. But whether or not the overall results are better than (or even comparable to) traditional hip replacement surgery remains a subject of much debate.

Ayres takes the middle ground. While MIS has been shown to improve recovery in the short term, these results have occurred primarily in studies involving higher-functioning, motivated, younger patients with relatively straightforward anatomy at high-volume centers, he says. Once you look beyond these selected parameters the number of undesirable outcomes often begins to rise.

Problems include nerve and artery injuries, wound healing problems, infection, fracture, prosthetic joint dislocation, leg length differences, and diminished ingrowth, which can be devastating. In many instances, the downside risks of MIS may outweigh its potential advantages.

As a result, Ayres says pure MIS was a wave that "seems to have crested a few years ago and has subsided somewhat. These days, many hip replacement surgeons have tailored their practice, so they do excellent muscle, capsule and tendon sparing surgeries through smaller incisions than were common just a few years ago," which are in the range of 10-12 cm (vs. 6-10 cm).

Print | Email | Discuss this article

| Share |

READERS' COMMENTS

Click here to post a comment

Add your Comment All posts are sent to the administrator for review and are published only after approval. ArabianBusiness.com reserves the right to remove any comment at any time for any reason. Please keep your responses appropriate and on topic. Arabian Business would like to point out that only comments relevant to the story will be published. Any containing personal insults or inappropriate language will not be approved.
Name *
Remember me on this computer
Email *	(Your email address will not be published)
City
Country
Subject *
Comment *
Notify me of further comments
Enter the words above *
Please click post only once - your comment will not be published immediately.

MORE FROM ARABIANBUSINESS.COM