Minimally invasive total hip replacement

One of the most significant advancements in total hip replacement is the recognition that the procedure can be done with less invasive techniques which allow the patient to recover faster. This has even progressed to the point that some patients are able to have their surgery accomplished as an outpatient procedure. The patients’ recovery is so much different than previously performed operations, that nurses have labeled these patients “turbo hips”.

New implants have been designed to reproduce the normal motion and function of the replaced joint. These new designs incorporate new materials (metals, plastics, and ceramics) and new biologically active coatings for the implants. These materials include highly crosslinked polyethylene for the hip and knee. This new plastic has been approved by the F.D.A. for regular use in the United States. Laboratory tests have shown implants made of this material to last two or three times as long as previous types.

The less invasive approach can be combined with the new implant designs. Surgeons can insert the prosthesis using minimally invasive techniques resulting in less trauma to the patient and the tissues surrounding the hip or knee. This decrease in magnitude of soft tissue trauma has a number of benefits for the patient. First and most obvious, the scar is significantly smaller. This has more than a cosmetic value as there is less to heal and thus the second major advantage is faster recovery from surgery of “smaller” magnitude. This has been recognized for years with arthroscopic surgery of the knee and even laproscopic gall bladder removal, appendectomy, hernia repair and even some more extensive tumor operations that are done partially or completely with the laproscope. When hip or knee replacement surgery is accomplished with smaller incisions, the patients will require fewer blood transfusions, will have shorter hospital stays and will return to work or recreation sooner. Patients report that a joint replaced with these new techniques is significantly less painful than with the previous, more generous, surgical exposures. Minimally invasive hip replacement can be performed either through two incisions each 1½ to 2 inches long or one 3 to 3½ inch incision.

We try to use this limited exposure on all patients, regardless of how long their hospital stay is intended to be. But it must be remembered that the first priority in performing the operation is to be able to see all that is necessary. Thus there are still situations that occasionally arise which require a larger, more extensive exposure.

The natural extension of minimally invasive surgery is to do the operation on patients as outpatients. In this situation, the patient receives appropriate education before surgery and then comes to the hospital the morning of surgery. After the operation, the patient is able to leave the hospital on crutches and be driven home to recover. The most current anesthetic techniques are used and appropriate medications given to minimize any risk of nausea and decrease pain.

This 50 year old woman had her hip replaced eight hours ago and is leaving her hospital room to go home. She is able to walk independently with crutches and is taking only oral medication for her pain.

a. Minor medical conditions should be well controlled: hypertension, asthma, thyroid conditions, stomach or gastrointestinal problems.

b. Contraindications include: diabetes, altered mental function (dementia, Parkinson’s disease), unstable cardiac status, renal failure, sleep apnea, and significant prostate obstruction interfering with adequate urination.

c. Age itself is not very important as long as other considerations are fulfilled.

2. The patient is willing to attend physical therapy before coming to the hospital. The patient must learn the use of crutches and the appropriate dislocation precautions before surgery.

3. There is an appropriate caregiver to help take care of the patient at home for the first few days after surgery. This is the same as for any outpatient surgical procedure.

4. The patient desires to have the operation as an outpatient. Obviously this would not be imposed on anyone.

To watch a total hip replacement performed using a single 7 cm incision click here

Example of minimally invasive hip compared to a “standard” operation of one year ago:

	This patient is a 54-year-old female with severe arthritis of her right hip. She has had treatment with arthritis medication that is no longer providing any significant relief and she wants to have her hip replaced. The x-ray shows the cartilage complete worn out and bone rubbing on bone.
	The surgical incision is marked over the hip. A solid line marks where the incision will be made and the dotted line illustrates where a traditional incision would otherwise have been created. The solid line measures under 3 inches.
	The exposure showing the acetabular prosthesis in place illustrates that very adequate visualization is achieved. The white plastic liner is seen inside the titanium shell.
	This photograph shows how the previous surgical exposure contrasts to the mini-incision. The incision is much longer and significantly more soft tissue disruption occurs.
	The three inch incision is closed with sutures that dissolve and is covered with steri-strips (tape to protect the incision).
	The final dressing is in place and the patient is ready to go back to her room and begin walking and prepare to go home.
	This is the x-ray of the patient’s hip after the surgery is complete.

SUMMARY OF NEW MINIMALLY INVASIVE HIP REPLACEMENT

Ø Allow the patient to realize the potential cosmetic benefits of a shorter incision

v New instruments and surgical techniques allow us to minimize the disruption of the tissues around the hip joint. This can make a big difference in how the patient feels following surgery.

v Procedure is performed through an opening of 3 to 3½ inches versus up to nine inches for a conventional procedure.

v Prosthetic implants used are existing, proven designs; only the instruments used and the surgical incision have been modified to enable the minimally invasive technique.

v Coordinated program emphasizing preoperative education and physical therapy to prepare the patient for a short hospital stay (8-12 hours) and a rapid recovery.

v Utilization of the most up to date anesthetic and pharmacologic techniques to minimize any problems associated with surgery and thereby allows the patient to recover with minimal pain, nausea, or other problem.

v The operation is performed using the “Mini Incision” to accomplish above goals.

v The patient returns home the day of surgery where they are most comfortable and familiar.

To view video footage of a hip replacement procedure click here. Video requires QuickTime, if you do not already have QuickTime and do not have a broadband connection, downloading the 5 megabyte QuickTime player may require a lot of time.

Minimally Invasive Knee Replacement

Total knee replacement can also be performed with much smaller incisions than previously. Some patients are candidates for what is truly a minimally invasive knee replacement. This is a unicompartmental knee replacement, which can be used on about 10% of patients who have degenerative arthritis in only part of their knee. All of the ligaments are preserved with this technique (anterior cruciate, posterior cruciate, medial collateral and lateral collateral). The knee replaced with a “uni” rehabilitates faster and seems to function much more like a normal knee than a traditional total knee replacement.

	The patient is a 63-year-old male who had the cartilage removed from his knee twenty-four years ago after an injury playing tennis. The x-ray before surgery shows one side of the knee worn out with bone rubbing on bone.
	The knee is draped and prepared for surgery. The three inch incision is marked on the front of the knee.
	View during surgery with the new unicompartmental prosthesis in place before the skin is closed.
	X-ray after surgery showing the new “uni” knee in place.

Minimally invasive total knee replacement

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