Total Hip Replacement Surgery

Hip replacement means removing the arthritic femoral head and replacing it with a femoral prosthesis and also replacing the arthritic socket of the hip.

There are an enormous number of prostheses available with many different philosophies and bearing components. Some use cement to fix to the patient’s bone and others avoid cement with a press fit technique. The bearing surfaces range from traditional metal and special plastic or polyethylene, to ceramic on ceramic, or metal on metal. The latter 2 are thought to be better wearing and tend to be used in the younger patients.

Mr Thomas uses well tried and tested prostheses that have an excellent survivorship and track record.

The surgery can be done through many different approaches but along with many specialist hip surgeons, he believes the best approach is the one that spares most of the important muscles around the hip, to get the best result in terms of soft tissue balance and avoidance of a limp after surgery. This is the posterior approach and can be done through a minimal incision in thin patients.

Post operative rehabilitation

The average length of stay in hospital is 5 days. Mr Thomas does operate on numerous young patients (under 50) with hip disease and this age group are often home at 3 days.
Patients are fully weight-bearing on their hip after surgery and may need crutches for up to 6 weeks afterwards. This is very variable amongst patients. Patients should have post operative physiotherapy to expedite recovery. If they are in a manual job, they will need at least 6 weeks off work. They should avoid driving for between 4 and 6 weeks.

Possible post operative complications

The majority of patients do extremely well after hip replacement surgery. It is an excellent operation for pain relief and restoration of movement and function. However complications can occur and delay recovery.

1. Infection – Incidence of deep infection is about 1%. This can mean prolonged antibiotics and even further surgery if it does not settle. Everything is done to minimise the risk with patients screened for MRSA pre-operatively, intravenous antibiotics at time of surgery and afterwards, surgery in a special laminar flow theatre and the surgeon wearing a “space suite” to minimise transmission of bacteria.

2. Thrombosis – Any surgery on the lower limb carries a risk of deep vein thrombosis and pulmonary embolus (clot in lung). There has been a lot of debate regarding giving patients medication to thin their blood preoperatively. Whilst in essence this sounds like a good idea, it can cause problems with bleeding during surgery and afterwards. This can then lead to a delay in recovery and an increased risk of infection. Mr Thomas therefore does not routinely give blood thinning agents apart from to those patients at high risk of thrombosis i.e previous clots, malignancy, blood disorders. The key to avoiding thrombosis is early mobilisation, so patients are asked to get out of bed as soon as possible after surgery. Mr Thomas uses foot pumps whilst patients are in bed and high dose Aspirin for 6 weeks. There is no definitive evidence in the literature as too what is best to use but this works well for Mr Thomas.

3. Dislocation – This is a specific risk to hip replacement and means that the hip can come out of joint with certain movements after surgery. In Mr Thomas’s practice, the risk is about 3% which is well below the national average. This comes down to surgeon technique and patient compliance post operatively. The use of larger femoral heads minimises this risk significantly.

4. Leg Length discrepancy – Mr Thomas strives to produce equal leg lengths. Computer software is used to template the surgery beforehand and intra-operative check are done to minimise the risk. Some hips will need to be lengthened slightly in order to achieve stability.

5. Metal ion issues – There is ongoing research into the affect of metal ions (cobalt and chrome) on the body in the long term. There is no evidence as yet that shows this to be harmful, but some patients may develop hypersensitivity reactions to metal. Patients with known metal allergies are best having ceramic bearings. The same is true of women of child bearing age requiring hip replacement.