William B Kurtz | Total Hip Replacement

Introduction

A total hip replacement is one of the most successful operations that orthopedic surgeons perform. A hip replacement is an elective surgery, which means patients decide if and when to have their hip replaced. As a physician, I never tell patients they have to have a hip replacement surgery, but many times surgery may offer the only possibility for pain relief. Although the surgery is elective, it is covered by most insurance companies; however, depending on your policy you maybe required to make a small co-payment. My philosophy is to give my patients as much information as they need to make informed decisions regarding their health and hip pain and then treat their hip pain according to their wishes.

A hip joint is basically a ball and socket joint. A hip replacement involves removing the ball (femoral head) and replacing it with a metal prosthetic ball. The femoral prosthesis is inserted into the hollow part of the femoral shaft. The socket of the pelvis is machined into a hemisphere and a metal hemisphere is inserted into the socket. The new metal ball and new metal socket form the new hip joint and allow the same and often times more motion than the native hip joint. The femoral and acetabular prosthesis are attached to your bones by creating a space in the bone that is slightly smaller than the metal prosthesis and then pressing the metal prosthesis into this tight space. Occasionally, the metal prosthesis is attached to the bone with bone cement. The parts are made of stainless steel, titanium, ceramic and/or polyethylene. I typically make an incision about 3-4 inches long for a hip replacement.

The purpose of this web page is to educate patients about the major aspects of hip replacement surgery. Many studies have shown that an informed patient will have less surprises and more satisfaction with their surgery. I do not intend to scare people away from getting their hip pain treated. Although the following information is a reasonable overview of what I consider the major aspects of hip surgery, it is not a substitute for a clinical consultation where I can directly answer your questions. If you would like more information, please schedule an appointment to see me.

History of Total Hip Replacement

Total hip replacements were developed in the late 1950s, and many of the early advancements in hip replacement were brought about by a British physician, Sir John Charnley. Over the last 50 years, surgical techniques, implants, and post-operative care have continued to evolve into the total hip replacement experience of today. Many different techniques and implants are available for hip replacement today, and good results can be achieved with most methods. The most important determinates of the patient’s outcome are the patient, the surgeon, and the hospital staff. Other factors which might have a smaller impact on a patient’s outcome include the patient’s pre-operative education, the type of components implanted, the surgical approach, the post-operative rehabilitation, and the length of the incision. Multiple studies have proven that hip replacement outcomes improve with increased volume by the surgeon and the hospital, so I feel that patients have the best outcomes with hip replacement surgery from surgeons and hospitals that specialize in hip replacements.

Surgical Approach

Total hip replacements can be preformed through a direct anterior approach, an anterior lateral approach, a lateral approach, a posterior approach, and a superior approach. Some surgeons will use 2 incisions, both the anterior and superior approach. Each approach has advantages and disadvantages.

Anterior Approach

The anterior (Smith-Peterson) and anterior lateral (Watson Jones) approaches have the advantage of not cutting the posterior capsule and posterior muscles. Most (90%) of hip dislocations occur posteriorly, and therefore anterior approaches typically have a slightly decreased dislocation rate. The anterior approach has the disadvantage of possibly injuring the abductor muscles while trying to insert the femoral component. The abductor muscles attach to the anterior part of the femur (greater trochanter), and therefore these muscles are typically in the way during the insertion of the femoral component. Surgeons will often use a special operating table to force the leg in a hyper-extended and externally rotated position in order to insert the femoral component into the femoral canal. Surgeons will also use a curved femoral replacement because the typical straight femoral components are extremely difficult to insert without injuring the abductor muscles. Dr. Joel Matta has introduced a mini-anterior approach that been getting a lot of press receently. Injury to the lateral femoral cutaneous nerve may result in numbness to the outside of the thigh, although this numbness usually does not bother patients very much.

Lateral Approach

The lateral approach (Hardinge) has the advantage of not cutting the posterior capsule and muscles (lower dislocation rate) and not inadvertently injuring the abductor muscles. The anterior 1/3 of the abductor muscles are dissected off the femur and then repaired at the end of the operation. The muscle belly is retracted and protected during the insertion of the femoral component. The disadvantage of the lateral approach is that the repaired abductor muscles must be protected after the surgery by limiting the patient’s weight bearing status. The patient may also limp if the abductor muscles do not heal or are damaged from the dissection.

Posterior Approach

The posterior approach (Kocher-Langenbock) has the advantage of not injuring the abductor muscles and the dissection can be extended in case more access to the femur or pelvis is necessary. The posterior approach is probably the most popular approach for a total hip replacement today. The disadvantage of the posterior approach is that the posterior capsule and muscles are cut during the approach. They are typically repaired at the end of the case which helps prevent dislocations, but the posterior approach does have a higher dislocation rate than the other approaches. Most surgeons limit the patient’s motion after surgery with a posterior approach to prevent any compromising leg positions that might cause a hip dislocation. Because the abductor muscles are spared, most patients have historically had the lowest rate of limping with the posterior approach.

Superior Approach

The superior approach is a relatively new approach that has recently been developed in Boston by Dr. Stephen Murphy. This superior approach is my preferred approach because I feel it offers the most advantages and the least disadvantages. Most notably, the hip stability after a superior approach is remarkable because neither the anterior nor posterior capsule is cut during this approach. In addition, the leg is never dislocated during the entire procedure and typically the hip can not be dislocated on the operating table even with the patient pharmacologically paralyzed and the leg in the most compromising positions. The excellent stability typically allows patients to move their leg after surgery without any restrictions on their motion. The leg is held in a normal position during the entire operation, so the blood vessels and nerves are not stretched and twisted like during other approaches. The femoral canal is prepared prior to the femoral neck is cut, so the femur is structurally more sound during the preparation of the canal. This fact may decrease the risk of femoral fractures during the canal preparation. Preparing the femoral canal before cutting the femoral neck also allows the surgeon to use a special leg length measuring device to recreate the patient's leg length and offset. Although larger body size makes any joint replacement a little harder, the superior approach seems to be easier than other approaches at dealing with the difficulties of joint replacement in larger patients. The relative easy with the superior approach in larger patients is because of the special leverage retractors and the inherent femoral stability while preparing the femoral canal. The disadvantages of the superior approach is that the surgeon can not deliberately lengthen a patient more than 1-2 cm because the intact joint capsule will not stretch more than about 1 cm. Another disadvantage of the superior approach is that it is more difficult to insert screws into the acetabular component, although I routinely do insert screws. Special equipment and training is required to perform this technique. The superior approach can easily be extended into a posterior approach if the surgeon needs more access to the femur or pelvis. The superior approach is most similar to the posterior approach without cutting the posterior capsule or short external rotator muscles and without dislocating the joint.

Two Incision

The two incisions technique combines the anterior approach and the superior approach. The acetabular component is inserted through a traditional anterior incision and the femoral component is inserted through a superior incision. Advocated of this approach claimed that the two incisions approach offered the hip stability of an anterior approach and the abductor protection of a posterior approach. Skeptics of the two incisions approached have published high complications rates and claimed damage to the abductor muscles from the blind preparation of the femoral canal and insertion of the femoral prosthesis without protecting the abductor muscles. Initially, there was considerable marketing and publicity surrounding this approach, but recent reports are mixed.

Good results after a total hip replacement can be achieved with any of the above approaches. Patients should allow the surgeon to perform the approach the surgeon is most comfortable with.

Bearing Surface options:

The bearing surfaces for total hip replacements are available in polyethylene, ceramic and metal.

Polyethylene (Plastic)

Polyethylene has the longest history of use in joint replacements. Polyethylene bearing surfaces have the advantage of a cushioned, forgiving surface and a long track record of good results. The polyethylene cup articulates with either a metal or ceramic head. The disadvantages of polyethylene are the fact that is wears down with time and it must have of a certain thickness that precludes the use of the largest head sizes. Polyethylene particles can a bone resorption process called osteolysis. Polyethylene is now highly cross linked which improves its wear characteristics, but long term follow up will be necessary to see how it holds up over 20 to 30 years.

Ceramic

Ceramic bearing surfaces have the advantages of excellent wear properties and no osteolysis. Unfortunately, ceramic bearing surfaces have been reported to fracture and squeak, and they also must have a certain thickness in the acetabular liner that precludes the use of the largest head sizes. Ceramic bearings are difficult to use in a revision hip replacement because the brittle nature of ceramics precludes their use with pre-existing implants.

Metal

Polished metal bearing surfaces have the advantage of good wear properties and the ability to make thin implants. Metal bearing surfaces therefore come in the largest head sizes. The use of larger head sizes increases the stability and range of motion before the components hit one another. Metal bearing surfaces increase the blood levels of metal ions and have been reported to cause a metal hypersensitivity reaction in select patients. Currently, women who are contemplating child birth and patients with renal failure should probably not have metal bearing surfaces. The increased metal ions in the blood are excreted in the urine and have not been shown to increase cancer risks.

Pre-operative Joint Replacement Education Class

· Multiple studies have shown that pre-operative education improves patient’s outcomes after joint replacement surgery.

· Baptist Hospital offers a free 3 hour pre-operative instructional class.

· Although it is not imperative, I strongly recommend that my patients attend this class.

· During this class,

o you will meet with the nurses that will be taking care of you after your surgery

o discuss what you can expect after surgery

o talk about what you need to bring with you to the hospital

o discuss whether you plan to go home with a home health nurse visiting you in your house or to an inpatient rehabilitation center

· The pre-operative joint class is offered Tuesday, Wednesday, and Thursday mornings.

· At the end of the pre-operative joint class, you will meet an anesthetist to discuss with him/her your anesthetic options. You should bring a list of all your medications and their doses and ask which medications you should take the morning of your surgery.

· A nurse will also draw your blood for routine pre-operative lab work.

Medical Clearance

· Dr. Kurtz typically informs the patient’s primary care doctor that the patient intends to have an elective joint replacement. Occasionally, the patient’s primary care doctor may recommend an additional pre-operative test or lab work that Dr. Kurtz does not routinely check. This pre-operative medical clearance helps Dr. Kurtz prevent any peri-operative medical complications.

· Depending on when you last visited your primary care doctor and what ongoing medical issues you have, your primary care doctor may request to see you prior to clearing you for surgery.

· If you have decided to pursue a joint replacement, inform your primary care doctor, so they can decide whether they need to set up a clinic visit with you prior to surgery.

· If you see a cardiologist, pulmonologist, or other specialist, please inform them of your intention to have a joint replacement, so they can clear you for surgery as well.

· If you do not have a medical doctor, Dr. Kurtz will decide if you need to find a primary care doctor before your joint replacement surgery.

· If you have any active infections before your surgery, you must contact Dr. Kurtz’s office, and your surgery will likely need to be rescheduled for a later date.

· If you need or plan to have any dental work done in the next year, you should take care of it at least one week before the operation.

Blood Donation

· Patients are welcome to donate their own blood three to four week prior to their surgery at the Nashville American Red Cross with the intention of receiving their own blood after surgery should the need arise.

· If you donate your own blood before surgery, please remind me prior to the operation, so I can be certain that you receive your own blood.

· As the likelihood of needing a blood transfusion is relatively low, I neither encourage nor discourage pre-operative blood donation.

· Patients with anemia and relatively low pre-operative blood levels (hematocrit) are more likely to need a blood transfusion.

· Patients with serious medical problems are also more likely to need a blood transfusion.

· Unfortunately, if we do not use your blood after surgery, your blood will not be given to anyone else and will be thrown out.

Medicines

· Certain medications need to be stopped before your surgery; however, before stopping any medications, you must talk with your prescribing physician to make sure it is safe for you to stop the medication.

· The following medicines typically need to be stopped a week before your surgery:

o Aspirin

o Coumadin (Warfarin)

o Plavix (Clopidogrel)

§ Patients with drug eluding stents in their heart must be especially careful about discontinuing Plavix for even a short period of time as that could cause instant stent thrombosis, which can be lethal.

§ Patients on Coumadin or Plavix will often need to start a temporary short acting blood thinner called Lovenox when they stop their Coumadin or Plavix.

· The following medicines typically need to be stopped three days before your surgery:

o All “non-steroidal” anti-inflammatory drugs

§ Advil

§ Motrin

§ Alleve

§ Naprosyn

§ Celebrex

· The following medicines typically need to be stopped one day before your surgery:

o Glucophage (Metformin)

· If you are uncertain whether you need to stop a particular medication, contact my office.

· All other medications should be continued unless Dr. Kurtz or your medical doctor instructs you otherwise.

Day of Surgery

· Patients are asked not to eat anything for 8 hours before their surgery which typically means nothing after midnight.

· Most of your normal medicines should be taken the morning of your surgery with a small sip of water. Please ask the anesthesiologist at your pre-operative visit which medicines you should take.

· Patients report to the admission office on the first floor and will be taken up to the 5^th floor pre-admission floor.

· Patients will see Dr. Kurtz in the holding room prior to the operation.

· Family members can wait in the family waiting room on the 4^th floor

· After the surgery, Dr. Kurtz will update your family members about how the operation went and how you are doing.

· The patient will typically spend ~ 2 hours in the recovery room before being taken to their hospital room.

· Family member can wait in the patient’s private room for the patient to arrive.

Wound Closure

· I feel strongly that the wound closure is as important as the insertion of the components..

· I therefore close the surgical incision with both interrupted and running suture in order to help evenly distribute the force on the skin edges.

· All of the sutures dissolve over the following 6 weeks.

· I also apply Dermabond (similar to Super Glue) to the incision after it is closed.

· The incisions typically do not bleed or drain after surgery.

· The water-proof dressing that is applied in the operating room typically does not need to be changed, and most patients remove the dressing about a week after the operation.

During your hospital stay

· Pain medicine is custom tailored to every patient's need.

· Most patients received both a long acting oral pain medicine and additional short acting oral pain medicine as needed.

· Patients will receive IV antibiotics for 24 hours after surgery.

· Patients will receive a blood thinner for 3 weeks.

· Patients will wear compression stockings and foot pumps while in the hospital.

· Patients are encouraged to walk immediately after surgery.

· Patients are encouraged to shower the day after surgery.

· Physical therapists will work with each patient multiple times each day helping them learn how to safely walk.

· All IVs and catheters are removed once the patient is medically stabilized, usually 1-2 days after surgery.

· I typically see every patient at least once a day and often times twice a day. I also try to round on my patients over the weekend, but occasionally, weekend rounds maybe covered by one of my partners

· The hospital stay is usually about 2-3 days.

Leaving the hospital

· Typically, patients will determine if they plan to go home or to a rehabilitation facility during their pre-operative visit.

· The orthopedic social worker will evaluate your condition after surgery and help determine how much help you need at home, and contact your insurance company to see what help is covered.

· The physical therapist, social worker, and Dr. Kurtz will determine whether you might be able to go home, to a rehabilitation facility, or a short-term nursing home.

· Patients will be discharged with a prescription for pain medication and a blood thinner.

· If the patient is taking the blood thinner, coumadin, your blood will be drawn at home or at a lab every Monday and Thursday for the next 3 weeks. You must also make sure that Dr. Kurtz’s assistant receives the results of your blood tests, and changes the dose of coumadin as needed.

Follow up

· Patients first follow up is between 2 and 4 weeks after surgery

· Patients second follow up is ~6 weeks after the first visit.

· Patients are then followed on a yearly basis for 2-3 years.

· Every joint replacement patient should have an x-ray of their replacement every 2-3 years regardless if they are having pain or not.

Risks of a total hip replacement

Dislocation: The ball of the new hip joint may become dislodged from the socket. The risk of this occurring can be lessened with proper component positioning, certain surgical approaches (Superior Approach to total hip replacement) and with larger femoral head sizes. If a posterior hip approach is used, then Dr. Kurtz ( and most orthopedic surgeons throughout the country) will restrict your motion for ~ 3 months after surgery to help decrease the risk of dislocation. If a superior approach is used, then Dr. Kurtz will most likely not restrict your motion after surgery. If your total hip dislocates, Dr. Kurtz will manipulate your leg under sedation and place the ball back in the socket. Unstable hip replacements occasionally need to be revised to correct the instability if it keeps occurring.

Unequal Leg Lengths/Offset: There are two reasons why surgeons occasional lengthen a leg during hip replacement surgery. First, if a hip replacement is unstable with the trial components, a surgeon may deliberately choose to increase the length of the leg in order to prevent the hip from dislocating after surgery. Second, the surgeon may not know or be able to accurately measure the length of the limb. Orthopedic surgeons rely on pre-operative templating (component sizing), intra-operative measurements, intra-operative x-rays, and/or intra-operative soft tissue tension to make a calculated estimate of the limb length. Most published results report average limb length within 1 cm of the other side. Only about 1/3 of patients with documented leg length inequalities have problems from the leg length, but subtle differences in outcomes are likely with just minor leg length changes. If the unequal lengths are bothersome, a lift can be built or inserted into the shoe of your shorter leg. Dr. Kurtz is currently studying a new technique of measuring leg length and offset in hip replacements and most times the leg length can be selected within 1-2 mm of the intended length. In addition, the excellent hip stability with the superior approach prevents Dr. Kurtz from having to deliberately lengthening the leg to obtain a stable hip joint.

Blood Clots: Blood clots in your leg veins are possible after any surgery on the lower extremities. The occurrence of blood clots can be minimized with blood thinners, foot pumps, and early mobilization. The main danger of blood clots is if they dislodge and travel to your veins in your lungs. This phenomenon is called a pulmonary embolus and can result in respiratory difficulty, chest pain, or even death. Blood clots may or may not hurt or cause swelling in your leg and can occur anywhere in either leg. If you have unexplained pain or swelling in your legs, let Dr. Kurtz know as he may order a duplex ultrasound to look for a blood clot. If you feel chest pain or breathing difficulties, you should call 911 and then call Dr. Kurtz. The risk of these clots causing death has been drastically reduced, and is less than 0.1%. The treatment for a proven blood clot is additional blood thinners, and occasionally a filter in your veins.
Infection: A hip infection after a hip replacement is a serious complication and can cause significant morbidity. Antibiotics are given both before and 24 hours after surgery to decrease the risk of infection, but an infection can still occur in the weeks or even years after the surgery. An infection usually requires additional surgery to treat the infection. The infected tissue and often the prosthesis are removed during that surgery. If the components are removed, a revision hip prosthesis can sometimes be inserted months later if the infection clears, but sometimes the patient is left without a hip joint. Although patients rarely have life threatening problems from their joint infection, an infection is a devastating complication. After any joint replacement, antibiotics should be taken before any major invasive procedure, including major dental work or colonoscopy.
Component Loosening: Occasional the bone will not grow into the implanted components. The components may loosen and change position. The motion of the loose component may cause pain and require another surgery to revise the components.

Limp: Many patients with hip arthritis have a limp before they undergo a hip replacement due to the constant pain and muscle weakness. It often takes a few months before patients learn to walk without a limp and the muscles become strong enough to support the body weight without limping. Rarely surgery may create a new limp. Occasionally, a limp may never go away, and the patient may need to use a cane or walker. Typically, any limp after a hip replacement is painless and resolves with time.

Bearing surface: Each bearing surface has its unique risk. Polyethylene bearings carry the risk of wearing out and causing osteolysis. Ceramic bearings can squeak and break. Metal bearing surfaces can cause a hyper-sensitivity allergic reaction and release of metal ions into the blood and surrounding tissue.

Nerve Injury: Although extremely rare, nerves to your leg and feet can be injured by the surgery. If the nerve has been stretched, its function will often return. If the nerve has been cut or irreparably damaged, you may need a brace for your ankle or knee to walk.

Bleeding: No major blood vessels are typically encountered during primary hip replacement, but excessive bleeding can still occur from small vessels during or after surgery. A post-operative hematoma can sometimes can mild pain or wound complications. Patients will sometimes require a blood transfusion to keep their blood levels at an acceptable level.

Fracture: The bone around the hip replacement can break during or even years after surgery. If the fracture occurs during surgery, it is usually fixed with wires and screws. If the fracture occurs after surgery, then additional surgery will depend on the location of the fracture and the fixation of the hip replacement.

Need for Further Surgery: Although hip replacements often last 20 to 30 years, hip replacements occasionally fail sooner than expected for reasons outlined above. Other problems can also arise that require additional surgery, including: abnormal bone formation or continued hip pain.

Death: Death after a hip replacement can rarely occur from a medical or heart problem that arise or worsen after the surgery. A blood clot that blocks vessels in the lungs or stress placed on the body by more than the usual amount of bleeding can also cause significant medical problems and/or death. The death rate after a joint replacement is significantly decreased with increased patient volume by the hospital and surgeon.

Other Problems: These complication listed above cover the most common problems associated with hip replacement. Other unforeseeable problems could arise with any hip replacement surgery.

Preventing complications:

If an infection develops anywhere in your body after a hip replacement, get immediate care. Preventing a joint infection is easier than treating an established joint infection.
Before any major dental, urinary, or rectal procedure, we need to take a dose of antibiotics before the procedure. Please call my office with any questions.
Always mention to any doctor performing an invasive procedure on you that you have a hip replacement.

Revision Hip Surgery

Replacing a previously inserted prosthesis is a more difficult surgery with a less predictable outcome than the first surgery. Each case has its own unique problems and risks. In most cases, the risks are greater than the risks with first-time surgery. The outcomes following revision surgery have improved over the years.