Other popular names
- Hip resurfacing arthroplasty
Who does it affect?
Patients with advanced arthritis of the hip may be candidates for either traditional total hip replacement (arthroplasty) or hip resurfacing (hip resurfacing arthroplasty). Each of these procedures is a type of hip replacement, but there are important differences. Your orthopaedic consultant will talk with you about the different procedures and which operation would be best for you.
Unlike hip replacement, hip resurfacing is not suitable for all patients. Generally speaking, the best candidates for hip resurfacing are younger (less than 55years), usually but not always male, with strong, healthy bone. Patients that are older, female, smaller-framed, with weaker or damaged bone are at higher risk of complications, such as femoral neck fracture.
What is Hip Resurfacing?
The hip is a ball-and-socket joint. In a healthy hip, the bones are covered with smooth cartilage that enables the femoral head and acetabulum to glide painlessly against each other.
In a traditional total hip replacement, the head of the thighbone (femoral head) and the damaged socket (acetabulum) are both removed and replaced with metal, plastic, or ceramic components.
In hip resurfacing, the femoral head is not removed, but is instead trimmed and capped with a smooth metal covering. The damaged bone and cartilage within the socket is removed and replaced with a metal shell, just as in a traditional total hip replacement.
Revision or redo hip surgery is required when hips fail. Hips can fail for a variety of reasons. The most common include:
- Aseptic loosening – this classically happens on traditional metal on plastic hip replacements, when the plastic liner has been worn away by the metal ball. This can be associated with quite a significant amount of osteolysis or erosion of the bone by cells involved in the inflammatory process.
- Infection – this occurs in 1-2% of cases and can require a 2-stage revision hip surgery with 8-10 weeks in between and a six-week course of antibiotics.
- Fractures – around the implants.
- Dislocation – these are very difficult patients to treat. Classically dislocation occurring early is due to malposition of the implant with dislocation occurring later associated with a wide variety of factors. Treatment options include constrained cups, larger heads or reposition of the implants.
Revision or redo hip surgery is technically demanding and complex surgery.
The result following a redo or revision hip surgery will never be as good as after a primary operation. This is because there is increased risk of infection, dislocation, nerve damage together with prolonged recovery due to scarring.
There are a number of implants and methods available to surgeon. It is my preference to use revision implants from Stryker along with their uncemented or Trabecular MetalTM cup together with the Restoration uncemented modular stem. This implant allows me the flexibility and versatility required to treat this condition.
Advantages of Hip Resurfacing
The advantage of hip resurfacing over traditional total hip replacement is an area of controversy and continued discussion amongst orthopaedic surgeons and a great deal of research is currently being done on this topic.
- Allow a return to as near normal function and activity as is possible with an artificial implant.
- Have excellent survivorship in experimental conditions - have been around for 15 years
- Hip resurfacings may be easier to revise. This is because the components (called implants) used in hip replacements and hip resurfacings are mechanical parts, they can, and do, wear out or loosen over time. This typically occurs between 10 and 20 years after the procedure, although implants may last longer or shorter periods of time.
- If an implant fails, an additional operation may be necessary. This second procedure is called a revision and it can be more complicated than the initial operation. Because hip resurfacing removes less bone from the femur (thighbone) than a traditional hip replacement, many surgeons believe it is easier to exchange implants that fail after hip resurfacing.
- Decreased risk of hip dislocation. In hip resurfacing, the size of the ball is larger than in a traditional hip replacement and it is closer to the size of the natural ball of your hip. Because of this, it may be harder to dislocate.
- More normal walking pattern. Several studies have shown that walking patterns are more natural following hip resurfacing compared to traditional hip replacement.
- Greater hip range of motion. Hip resurfacing patients are usually able to move their hips in a greater range of motion that total hip patients. However, certain total hip implants can achieve the same range of motion as hip resurfacings.
Disadvantages of Hip Resurfacing
- Femoral neck fracture. A small percentage of hip resurfacing patients will eventually break (fracture) the thighbone at the femoral neck. If this occurs, it is usually necessary to convert the hip resurfacing into a traditional hip replacement.
- A femoral neck fracture is not possible with a traditional hip replacement because the femoral neck is removed during this procedure. However, fractures around the implants can still occur with a traditional hip replacement.
- Metal ion risk. In hip resurfacing, a metal ball moves within a metal socket. Over time, this leads to the production of tiny metal particles called ions. Some patients may develop sensitivity or allergy to the metal particles, which may cause pain and swelling. Also, there are concerns that the metal particles may increase the risk of cancer, although this has never been proven. Some types of traditional hip replacements also consist of a metal ball and a metal socket and these replacements run the same potential risks.
- Hip resurfacing is a more difficult operation. Hip resurfacings are more difficult that total hip replacements for surgeons to perform. As such, a larger incision is usually required for a hip resurfacing.
Hip Resurfacing v Traditional Hip Replacement
Hip arthritis typically causes pain that is dull and aching. The pain may be constant or it may come and go. Pain may be felt in the groin, thigh, and buttock, or there may be referred pain to the knee. Walking, especially for longer distances, may cause a limp.
Some patients may need a cane, crutch, or walker to help them get around. Pain usually starts slowly and worsens with time and higher activity levels.
Patients with hip arthritis may have difficulty climbing stairs. Dressing, tying shoes, and clipping toenails can be difficult or impossible. Pain may also interfere with sleep.
Your consultant will readily be able to diagnose hip arthritis. This will be done through a physical examination, supported by X-ray. The x-ray may show loss of the cartilage space in the hip socket and a "bone-on-bone" appearance. Bone spurs and bone cysts are common.
Depending upon the extent of your condition, you may be referred for an MRI, which will provide a greater level of detail to your consultant.
Hip arthritis is never life threatening, the main aim of treatment is therefore symptomatic for pain and to try to keep mobility and range of movement of the joint. Treatment follows a progression from simple measures to major surgical intervention. There are a range of non-surgical approaches to be exhausted prior to the need for surgical intervention:
- Exercise – Low impact exercise such as walking, swimming and cycling keeps muscle strength and tone. Hip joint stretches to keep the hip supple are beneficial. A consultation with a physiotherapist for education and a home exercise program can be useful.
- Walking stick – Using a walking stick in the opposite hand reduces load in the hip and usually increases your walking distance. A strong stick of correct length with a non-slip rubber end is best.
- Paracetamol – A simple but safe analgesic when used correctly. Often needs to be used 3 or 4 times a day (1000mg / 2 tablets on each occasion). This can be safely used by most people at prolonged periods at these doses.
- Natural remedies – Often not proven but some people gain relief from various naturopathic potions, magnets, acupuncture and the like. This affect may be placebo but some plant substances have proven anti-inflammatory effects. You should check the use of these with your local Doctor as some may react with other medicines or be dangerous.
- Glucosamine and Chondroitin Sulphate – The most common arthritis remedies at the present time. There is some early evidence that over time they may help to maintain articular cartilage and slow progression of Osteoarthritis. Nothing can ‘put cartilage back’ after Osteoarthritis is established. Some people also report a reduction in arthritis symptoms when taking these substances. Their main side effect is diarrhoea. They should not be taken if you are pregnant or allergic to shellfish.
- Fish oils – Have been associated with some improvement in cartilage quality and may be beneficial.
- Anti-inflammatories (NSAID’s) – Several types of Non-steroidal anti-inflammatory drugs are available. They can be very effective in reducing pain and swelling associated with osteoarthritis. All these medications have potential side effects and are not always tolerated. The most common effects are: exacerbating asthma, stomach upset (ulcers etc), increased blood pressure and ankle swelling.
- Weight loss – There is no doubt that if you are above ideal weight, weight loss can have a significant impact in reducing pain from osteoarthritis. Weight loss can also reduce the risk of anaesthetic complications and wound healing. Many people after losing weight no longer need surgery for their Osteoarthritis. You may be given an ideal weight to attain prior to consideration for surgery. Consulting a dietician may be beneficial.
- Injections – A hip injection is often used by your orthopaedic consultant to differentiate between back pain and hip joint pain. An injection is given to ‘numb’ the hip and you then keep a record of the pain experienced. Sometimes steroids are used to provide longer relief of pain. The procedure is done under X-ray guidance with a small risk of infection.
Once all non-surgical means have been exhausted, a comprehensive evaluation by your orthopaedic surgeon will help you determine if you are a good candidate for hip resurfacing.
Before your procedure, the Anaesthetist evaluate you, review your medical history and discuss anesthesia choices with you. You should also have discussed anesthesia choices with your surgeon during your preoperative clinic visits. Anesthesia can be either general (you are put to sleep) or spinal (you are awake but your body is numb from the waist down). Your surgeon will also see you before surgery and sign your hip to verify the surgical site.
A hip resurfacing operation is complex and typically lasts between 1 1/2 and 3 hours.
Your surgeon will make an incision in your thigh in order to reach the hip joint. The femoral head is then dislocated out of the socket. Next, the head is trimmed with specially designed power instruments. A metal cap is cemented over the prepared femoral head. The cartilage that lines the socket is removed with a power tool called a reamer. A metal cup is then pushed into the socket and held in place by friction between the bone and the metal. Once the cup is in place, the femoral head is relocated back into the socket and the incision is closed.
After the surgery you will be taken to the recovery room, where you will be closely monitored by nurses as you recover from the anesthesia. You will then be taken to your hospital room.
Most patients are able to return home 1-4 days following surgery. All patients will need someone to take them home and be with them on the night following return home.
The anaesthetic will wear off after approximately 6 hours. Simple analgesia (pain killers) usually controls the pain and should be started before the anaesthetic has worn off.
You may begin putting weight on your leg immediately after surgery, depending on your consultant’s preferences and the strength of your bone. You may need a walker, cane, or crutches for the first few days or weeks until you become comfortable enough to walk without assistance.
A physical therapist will give you exercises to help maintain your range of motion and restore your strength. You will continue to see your orthopaedic surgeon for follow-up visits in his clinic at regular intervals.
You will most likely resume your regular activities of daily living by 6 weeks after surgery
The large bandage is normally removed 24-48 hours after surgery.
The non-stick sterile dressings on the wounds are replaced with clean waterproof dressings. The larger incision is closed using sutures, which are removed after 10 days.
Return to normal routine
Bathing and showering
The wounds should be kept clean and dry until the wound has sealed. Showering is fine and the waterproof dressings can be changed afterwards. Bathing is best avoided until the wounds are sealed, typically 10 days after surgery.
In summary, whilst the wounds are wet - keep them dry and when the wounds are dry, you can get them wet!
Surgery is followed by a prolonged course of physiotherapy. This requires a commitment to undertake this rehabilitation in order to achieve the best possible result (at least half an hour per day for 6 months). It is vitally important to stay within the post-operative activity restrictions an physiotherapy guidelines to avoid damaging stretching your reconstructed ligament.
Return to work
The timing of your return to work depends on the type of work and your access, however, the following is a general guide:
- Desk work: as soon as pain allows and you can travel easily to and from work (2 weeks)
- Light duties: if the job allows partial use of crutches or limited walking (2-5 weeks). If the job involves standing for prolonged walking, bending, lifting, stairs but no squatting (7-8 weeks)
- Heavy duties: full squatting, heavy lifting, digging, in and out of heavy machinery, ladder work etc (3-4 months)
When you can walk without crutches or a limp and be in control of your vehicle (about 4-6 weeks).
As with any surgical procedure, there are risks involved with hip resurfacing. Your surgeon will discuss each of the risks with you and will take specific measures to help avoid potential complications.
Although rare, the most common complications of hip resurfacing are:
- Blood clots. Blood clots in the leg veins are the most common complication of hip resurfacing surgery. Blood clots can form in the deep veins of the legs or pelvis after surgery. Blood thinners such as warfarin (Coumadin), low-molecular-weight heparin, aspirin, or other drugs can help prevent this problem.
- Infection. You will be given antibiotics before the start of your surgery and these will be continued for about 24 hours afterward to prevent infection.
- Injury to nerves or vessels. Although it rarely happens, nerves or blood vessels may be injured or stretched during the procedure.
- Femoral neck fracture
- Risks of anesthesia
All these risks are uncommon and in total, the chance of you or your knee being worse off in the long term is about or less than 1%.