Weight reduction

Weight reduction will reduce the stresses on your hip joint and may allow you to bear weight through the joint more easily. To find out whether weight loss is a good idea go to the NHS Body Mass Index (BMI) calculator at NHS BMI Calculator. This will enable you to calculate your BMI according to your height, weight, age, gender, ethnicity and activity level. The calculator will also tell you whether you should try to lose some weight. The calculator only sets you a target that is likely to be achievable and if you really want to help your health, getting into the green zone should be your long-term goal. Many people find it difficult to lose weight when they have a painful hip or knee that makes it difficult to exercise. There is no absolute weight limit for hip or knee replacement surgery but as your BMI increases, so do a number of the risks associated with major joint replacement.

Physiotherapy

Useful advice on the role of physiotherapy can be seen at the Versus Arthritis website

Medications for arthritis

Useful guidance on analgesics (pain killers), anti-inflammatories and other medications can be found at the  NHS Information website. 

Joint Injections

There are a number of options when considering injections into painful joints to alleviate or relieve symptoms.  On a positive note, these injections can usually be undertaken by a radiologist (x-ray and imaging doctor), under ultrasound guidance, as an out-patient procedure and do not require any hospital admission.  While injections in joints are normally quick and less painful than surgery, they do carry a very small risk of a bug getting into the joint and, if this occurs, further joint deterioration will be accelerated.  Injection options include:

Steroids – Helpful guidance on steroid injections can be found on the NHS Information website.

Hyaluronic Acid – Healthy joints contain a small amount of lubricating fluid (synovial fluid) that is manufactured by the membrane that lines the walls of the joint (the synovium). The synovial fluid lubricates the cartilage surfaces of the joint, provide the cartilage cells with their nutrients and remove the waste products of their metabolism. The synovial fluid is a good lubricant because it is more viscous than blood and other body fluids. The viscosity is due to the presence of long chain molecules of hyaluronic acid. In arthritic joints the hyaluronic acid molecules are damaged and hyaluronic acid injections help restore the synovial fluids lubricating properties. There is some evidence that hyaluronic acid injections reduce the inflammatory changes in a deteriorating joint and that the benefits can last for up to six months. However, hyaluronic acid is more expensive than steroid and there is no robust evidence that a hyaluronic acid injection works any better than a steroid injection. On this basis the National Institute for Health and Care Excellence (NICE) recommends that this treatment should not be available as an NHS treatment. NICE guidance on Hyaluronic acid injections

Platelet rich plasma (PRP) – The platelets in our blood contain numerous cargo granules that contain hundreds of proteins and hormones needed to stimulate and control would repair. To obtain PRP, approximately 40cc of a patient’s blood is taken. The sample is placed in a centrifuge and spun to separate the different blood components. The platelets are then extracted from the sample and injected into the patient’s painful joint. Current evidence suggests that the PRP dampens down the inflammatory processes that occur as a joint is becoming arthritic and that this may make the joint more comfortable for a period of time. However, there is no convincing evidence that PRP can stop or reverse the arthritic process.

Stem cells, gene expression therapies – In the future, stem cell and gene expression therapies may enable us to slow, halt or reverse the damage that causes arthritic joint degeneration. In both fields, extensive laboratory research is ongoing and clinical trials will follow. There are already more than sixty UK clinics offering stem cell treatments for a variety of conditions. The stem cells are extracted either from fat or bone marrow and can be re-injected into painful joints or cultured in a lab (expanded) to increase their numbers before being re-injected. To date, no one has yet published any robust data showing benefit for patients with degenerative hip disease. Indeed no one yet knows how many viable stem cells are obtained when they are taken from different sources or how the extraction and processing techniques affect the cells. The research team at the South West London Elective Orthopaedic Centre recently won a grant to study these questions and we anticipate that it will be many years before reliable and effective stem cell treatments are developed.

Problems that people typically describe when hip replacement should be considered include:

• When they are no longer able to maintain an acceptable quality of life through non-operative treatments.
• When they are experiencing difficulty finding a comfortable position to go to sleep and they are waking from sleep, often when they turn over.
• When their friends and family notice that they are limping.
• When they are finding it progressively more difficult to walk at a normal pace and notice that other people are having to slow down for them.
• When they are experiencing difficulty putting on their socks or cutting their toe-nails.

Soft tissue cooling devices are growing in popularity and can be hired by patients for use after operations such as hip replacement or hip arthroscopy. A number of such products are available and a number of our patients have used the ‘Game Ready’ product. (http://www.gameready.co.uk/Rental.html ).

After any surgical trauma, chemical mediators are released at the site of injury to increase blood flow. This is part of the tissue healing process. A side effect of the increased blood flow is tissue swelling and this irritates the nerves in the area. In consequence, the patient feels pain. Cooling devices reduce blood flow and impair nerve conduction in the tissues that they cool. This can reduce swelling and mean that the patient experiences less pain. However, the increased blood flow is a key element of tissue healing and it is possible that cooled tissues will heal slightly more slowly.

A number of our patients have reported that they found their cooling device very helpful and, thus far, we have not seen any adverse effects in the patients who have used them. While we do not promote their use, we have no objection to patients hiring such equipment and welcome feedback from anyone who chooses to use a cooling device after surgery.

If someone has rapid progressive joint deterioration after a steroid injection there are several possible explanations. 

1)    The most likely explanation is that the steroid injection was undertaken when the deteriorating joint was becoming progressively more symptomatic.  The injection partially masked this deterioration for a few weeks.  When the effect of the steroid began to wear off, the patient became aware of the further deterioration and attributed this to the steroid injection rather than the natural progression of their joint disease.

2)    There are reports of the metabolism of cartilage cells being adversely affected by some steroids. While most of the data on this phenomenon comes from laboratory studies and tissue culture specimens, there are rare clinical cases where rapid loss of joint space is observed on serial x-rays and the term chondrolysis is applied to this change.  While it is hard to say whether this process has been triggered or accelerated by steroid injections, if all other possibilities are excluded, it may be the explanation.

3)    If an infection has found its way into the joint, either through the bloodstream or when the steroid injection was undertaken, there is a risk that the infection remains in the tissues after hip replacement surgery and the infection settles on the new hip implants.  If this occurs, further surgery is usually required, and revision of the implants may be necessary.

If the possibility of an infection is being considered prior to primary hip replacement, the following strategies are available to help identify whether or not an infection is/was present prior to surgery.

1)    Pre-operative blood tests can be undertaken. These include:

1. Full blood count (FBC)
2. C-Reactive protein (CRP)
3. Erythrocyte sedimentation rate (ESR)
4. Procalcitonin (PCT)

2)    Joint aspiration under ultrasound or image intensifier guidance with 

1. Alpha Defensin Lateral Flow Test on synovial fluid obtained from the joint.
2. Microscopy and culture of fluid +/- tissue biopsies from the joint.

3)    Microscopy & culture of multiple tissue specimens obtained during surgery in aerobic and anaerobic environments with standard and enhanced culture media. 

If all pre-operative tests have failed to deliver an organism but there is still a significant index of suspicion that an infection is present in the joint, the following strategies can be followed:

1)     Intra-operative microscopy of tissue specimens from the joint is available at some centres. If greater than five neutrophils per high-power field, in five high-power fields, are observed on histologic analysis of periprosthetic tissue at ×400 magnification, the possibility of infection should be seriously considered.

2)     A single stage procedure can be undertaken with thorough joint debridement, irrigation of the tissues with antiseptics and implantation of a hip replacement. If one or both of the components are being fixed using cement, a cement option that is normally reserved for revision (redo) cases can be used. This will have a different antibiotic to the normal gentamycin impregnated cement, that is preferred for first time (primary) hip replacements.  If uncemented components are used, antibiotic can be put into the joint cavity prior to wound closure. The patient can then be kept on antibiotic therapy, at least, until the tissue culture results are known.

3)     A two-stage procedure can be undertaken.  In the first stage the joint is debrided, multiple soft tissue and bone biopsies are obtained. The joint can be irrigated with antiseptics and then reclosed.  Alternatively, the femoral head can be removed and an antibiotic loaded cement spacer can be put in its place, prior to wound closure.  If the latter option is taken, traction will need to be applied to the affected leg until the joint becomes comfortable enough to allow transfers to a chair.  If tissue culture does confirm the presence of an infection, discussion with the microbiology team will provide guidance on appropriate antibiotic therapy and the timing of the second for implantation of the new hip.

In addition to the normal risks of joint replacement surgery, there is the risk that bacteria in the tissues prior to surgery are not completely removed prior to implantation of the new hip, are not killed by antiseptics used during surgery and are not killed by the antibiotics given during surgery or the antibiotics in the cement that may be used to secure one or both of the new hip components.  

Any residual bacteria may find their way onto the surfaces of the artificial hip. Once on the components, the bacteria can divide, form colonies, become protected by a biofilm and be inaccessible to the body’s white blood cells or antibiotics that may be given.  If the bacteria are of low virulence and struggle to survive in the tissues, the patient may never know that their implants are infected.  Alternatively, if the bacteria are able to divide and flourish the patient will develop the symptoms and signs of an infected hip replacement. These can include:

1)    Pain

2)    Swelling in the tissues around the hip.

3)    Breakdown of the wound with discharge of pus.

4)    Formation of a discharging sinus tract from the infected joint to the skin.

5)    Spread of the infection into the bloodstream (Septicaemia)

6)    Spread of the infection to other tissues.

7)    Malaise, night sweats, a low grade or swinging pyrexia and death.

Approximately 80% of all joint infections present within the first year of surgery.  If the infection becomes apparent with the first four to six weeks of the hip replacement, a DAIR procedure can be undertaken. This involves debridement of the joint, antibiotic therapy and implant retention. Beyond the first four to six weeks, an infected joint is best treated by removal of the components, implantation of a new hip replacement and course of antibiotic therapy. Revision can be undertaken as a single or two-stage procedure depending on the infecting organism and the condition of the tissues.  Overall, revision for infection has a slightly better than 90% chance of eradicating the infection and providing a well-functioning joint.