Hip Resurfacing

• Introduction
• Resurfacing
• Arthritis
• Indications & Advantages
• Pre-op
• Day of your surgery
• Surgical procedure
• Post-operation course
• Special Precautions
• Risks and complications
• Summary

Introduction

Hip replacement has become necessary for your arthritic hip: this is one of the most effective operations known and should give you many years of freedom from pain.

Once you have arthritis that has not responded to conservative treatment, you may well be a candidate for a resurfacing procedure of the hip.

Resurfacing

A standard hip replacement replaces the acetabulum (hip socket) and the places a femoral component inside the femur (thigh bone).  Hip Resurfacing or bone conserving procedure replaces the acetabulum (hip socket) in the same way but resurfaces the femoral head. This means the femoral head has some or very little bone removed that is replaced with the metal component. This spares the femoral canal.

Resurfacing procedures may be indicated in the young patient (usually less than 55 years) who has osteoarthritis and wishes to maintain an active lifestyle. It is a more conservative and less traumatic alternative to Total Hip Replacement (THR).

Arthritis

Arthritis is a general term covering numerous conditions where the joint surface (cartilage) wears out. The joint surface is covered by a smooth articular surface that allows pain free movement in the joint. This surface can wear out for a number of reasons, often the definite cause is not known.

When the articular cartilage wears out, the bone ends rub on one another and cause pain. There are numerous conditions that can cause arthritis and often the exact cause is never known. In general, but not always, it affects people as they get older. This form of arthritis is referred to as Osteoarthritis.

Other causes include:

• Childhood disorders e.g., dislocated hip, Perthe's disease, slipped epiphysis etc.
• Growth abnormalities of the hip (such as a shallow socket) may lead to premature arthritis.
• Trauma (fracture)
• Increased stress e.g., overuse, overweight, etc.
• Avascular necrosis (loss of blood supply)
• Infection
• Connective tissue disorders
• Inactive lifestyle- e.g., Obesity, as additional weight puts extra force through your joints which can lead to arthritis over a period of time.
• Inflammation e.g., Rheumatoid arthritis

In an arthritic hip

• The cartilage lining is thinner than normal or completely absent. The degree of cartilage damage and inflammation varies with the type and stage of arthritis.
• The capsule of the arthritic hip is swollen.
• The joint space is narrowed and irregular in outline; this can be seen in an X-ray image.
• Bone spurs or excessive bone can also build up around the edges of the joint.
• The combinations of these factors make the arthritic hip stiff and limit activities due to pain or fatigue.

Diagnosis

The diagnosis of osteoarthritis is made on history, physical examination & X-rays. There is no blood test to diagnose Osteoarthritis (wear & tear arthritis).

Indications & Advantages

Resurfacing procedures may be indicated in the young patient (Less than 55 years) who has osteoarthritis and wishes to maintain an active lifestyle. It is a more conservative and less traumatic alternative to Total Hip Replacement (THR).

Advantages

The main advantage is that it is bone sparing in that it does not violate the femoral canal. This allows a Total Hip Replacement to be performed at a later date, if required, with little difficulty.

• Higher activity levels allowed
• Quicker recovery in hospital (2 to 5 days)
• Reduced bone damage and Osteolysis (erosion of bone) over time
• Reduced complications, especially reduced dislocation rate and reduced leg discrepancy.

Conventional Hip Replacement	Hip Resurfacing
Suitable for older patients	Suitable for younger patients
Femoral canal violation	Femoral canal left intact.
Metal on polyethylene, metal on metal or ceramic on ceramic articulation	Metal on metal articulation
Can wear out rapidly.	Longer lasting, with better wear characteristics.
Risk of dislocation.	Less risk of dislocation.
Leg length discrepancy.	Minimal or no leg discrepancy.
Osteolysis (bone wearing out)	Less risk of osteolysis.
Thigh pain	No thigh pain
May require revision surgery	Revision surgery less likely.
Requires restriction of activities	Able to be more active

Pre-op

Your surgeon will send you for routine blood tests and any other investigations required prior to your surgery.

You will be asked to undertake a general medical check-up with a physician.

You should have any other medical, surgical or dental problems attended to prior to your surgery.

Make arrangements for help around the house prior to surgery.

Cease aspirin or anti-inflammatory medications 10 days prior to surgery as they can cause bleeding.

Cease any naturopathic or herbal medications 10 days before surgery.

Stop smoking as long as possible prior to surgery.

Day of  Surgery

• You will be admitted to hospital usually on the day of your surgery.
• Further tests may be required on admission.
• You will meet the nurses and answer some questions for the hospital records.
• You will meet your Anesthetist, who will ask you a few questions.
• You will be given hospital clothes to change into and have a shower prior to surgery.
• The operation site will be shaved and cleaned.
• Approximately 30 minutes prior to surgery, you will be transferred to the operating room.

Surgical Procedure

An incision is made over the hip to expose the hip joint.

The acetabulum (socket) is prepared using a special instrument called a reamer.

The acetabular component is then inserted into the socket. This is sometimes reinforced with screws or occasionally cemented.

A liner which can be made of plastic, metal or ceramic material is then placed inside the acetabular component

The femur (thigh bone) is then prepared. The femoral head which is arthritic is cut off and the bone prepared using special instruments, to exactly fit the new metal femoral component.

The femoral component is then inserted into the femur. This may be press fit relying on bone to grow into it or cemented depending on a number of factors such as bone quality and surgeon's preference.

A trial reduction (putting the hip back into place) is performed to make sure everything fits well.

The real femoral head component is then placed on the femoral stem. This can be made of metal or ceramic.

- The hip is then reduced again, for the last time

- The muscles and soft tissues are then closed carefully.

Post-Operative

You will wake up in the recovery room with a number of monitors to record your vitals, (Blood pressure, Pulse, Oxygen saturation, temperature, etc.) You will have a dressing on your hip and drains coming out of your wound.

Post-operative X-rays will be performed in recovery.

Once you are stable and awake you will be taken back to the ward.

You will have one or two IV's in your arm for fluid and pain relief. This will be explained to you by your anesthetist.

On the day following surgery, your drains will usually be removed and you will be allowed to sit out of bed or walk depending on your surgeon's preference.

Pain is normal but if you are in a lot of pain, inform your nurse.

You will be able to put all your weight on your hip and your physical therapist will help you with the post-op hip exercises.

You will be discharged home or to a rehabilitation hospital approximately 5-7 days depending on your pain and help at home.

Sutures are usually dissolvable but if not are removed at about 10 days.

A post-operative visit will be arranged prior to your discharge.

You will be instructed to with crutches for two weeks following surgery and to use a cane from then on until 6 weeks post-op.

Special Precautions

Remember this is an artificial hip and must be treated with care.

AVOID THE COMBINED MOVEMENT OF BENDING YOUR HIP AND TURNING YOUR FOOT IN. This can cause DISLOCATION. Other precautions to avoid dislocation are:

Risks and Complications

As with any major surgery, there are potential risks involved. The decision to proceed with the surgery is made because the advantages of surgery outweigh the potential disadvantages.

It is important that you are informed of these risks before the surgery takes place.

Complications can be medical (general) or specific to the hip

Medical complications include those of the anesthetic and your general well being. Almost any medical condition can occur so this list is not complete. Complications include

• Allergic reactions to medications
• Blood loss requiring transfusion with its low risk of disease transmission Heart attacks, strokes, kidney failure, pneumonia, bladder infections.
• Complications from nerve blocks such as infection or nerve damage.
• Serious medical problems can lead to ongoing health concerns, prolonged hospitalization, or rarely death.

Specific complications

Infection

Infection can occur with any operation. In the hip this can be superficial or deep. Infection rates are approximately 1%.  If infection occurs it can be treated with antibiotics but may require further surgery. Very rarely your hip may need to be removed to eradicate infection.

Blood Clots (Deep Venous Thrombosis)

These can form in the calf muscles and can travel to the lung (Pulmonary embolism). These can occasionally be serious and even life threatening. If you get calf pain or shortness of breath at any stage, you should notify your surgeon.

Dislocation

This means the hip comes out of its socket. Precautions need to be taken with your new hip forever. If a dislocation occurs it needs to be put back into place with an anesthetic. Rarely this becomes a recurrent problem needing further surgery.

Fractures (break) of the femur (thigh bone) or pelvis (hipbone)

This is also rare but can occur during or after surgery. This may prolong your recovery, or require further surgery.

Damage to Nerves or Blood Vessels

Also rare but can lead to weakness and loss of sensation in part of the leg. Damage to blood vessels may require further surgery if bleeding is ongoing.

Wound irritation

Your scar can be sensitive or have a surrounding area of numbness. This normally decreases over time and does not lead to any problems with your new joint.

Leg length inequality

It is very difficult to make the leg exactly the same length as the other one. Occasionally the leg is deliberately lengthened to make the hip stable during surgery. There are some occasions when it is simply not possible to match the leg lengths. All leg length inequalities can be treated by a simple shoe raise on the shorter side.

Leg length inequalities are less likely to occur with a resurfacing procedure.

Wear

All joints eventually wear out. The more active you are, the quicker this will occur. In general 80-90% of hip replacements survive 15- 20 years.

Resurfacing procedures should last longer, but this has to be proven by long term studies and with the latest designs.

Failure to relieve pain

Very rare but may occur especially if some pain is coming from other areas such as the spine.

Unsightly or thickened scar

Pressure or bedsores

Limp due to muscle weakness

Discuss your concerns thoroughly with your Orthopaedic Surgeon prior to surgery.

Summary

Surgery is not a pleasant prospect for anyone, but for some people with arthritis, it could mean the difference between leading a normal life or putting up with a debilitating condition. Surgery can be regarded as part of your treatment plan—it may help to restore function to your damaged joints as well as relieve pain.