Osteoarthritis (OA) is the commonest joint degeneration condition in the world, resulting in huge amounts of pain and suffering, work loss, expense and disability. Ageing of western developed populations, soon to be followed by some developing countries such as China, will place an increasing burden on medical services as the occurrence of OA rises steadily with age. There will be an increasing need to provide medical and physiotherapy treatment for OA over the next 50 years and for many thousands of people this will involve joint replacement.
Medical interventions can be rated on a scale which calculates the improvement in quality of life which results and here hip replacement comes out top of all treatments. The 1960s saw its development into a standard treatment for hip arthritis but the 21st century has seen the technique evolve into a complex and predictable approach to many hip conditions, with excellent fifteen year plus results. Once conservative treatments have been exhausted due to a worsening joint then joint replacement becomes the standard choice.
Total hip replacement involves removal of the arthritic joint surfaces and their replacement with metal and plastic components. The top of the femur, the ball of the hip joint, is removed and the socket is reamed out to make it bigger to accept the new part. Cement is pressurized into the bony areas and a steel alloy femoral component with a ball and stem is inserted down the femur and a plastic cup of ultra high density polyethylene into the socket. The metal-plastic interface allows very low friction and wear, ensuring a long life for the joint.
On return from operation the physiotherapist will check the patient’s operative record, medical observations and assess the patient. Initial physio treatment consists of checking respiratory status and the muscle power and feeling in the legs to exclude nerve injury. Exercises are given to restore normal movement although an epidural can cause loss of movement in the legs and delay progress. The physiotherapist will then mobilise the patient with an assistant, taking care of the hip precautions, stand them up and walk them a short distance with elbow crutches or a frame.
Toes, ankles, quadriceps, hip flexion and buttock exercises continue to restore normal muscle activity to the legs and maintain the circulation. Routine painkillers should be taken as this helps patients get up and about and once safe they can get up three times a day or more with a helper to walk, toilet and wash. Usual precautions are taken and when sat out the chair must be the correct height and normally patients do not put their feet up whilst sitting.
Physiotherapists routinely teach and correct patients’ gait after hip replacement to improve joint movement, muscle strength and a normal walking pattern. On getting a patient up initially the physio will teach the “step to gait”, instructing the patient to place the crutches forward at first, place the operated leg between the crutches then following it by stepping to it with the unoperated leg. This technique is steady but slow and used when safety is key, and the next progression is to a “step through gait” where the unoperated leg then moves through past the operated leg into a more normal gait. The most advanced gait sees the operated leg and the crutches moving together at the same time and gait approaching normal.
Six weeks or so after the operation the patient will have a good gait, have reasonable muscle power and be able to do most functional activities such as a walk, climb stairs and ride in a car. They may then move on to a stick if stability or balance is difficult or the person is very old. Patients can now return to normal activities but need to maintain the hip precautions:
* Avoid hip flexion over 90 degrees by not sitting down in low seating, not sitting down or standing up too quickly, not bending over to the floor quickly and not crouching.
* Standing on the operated leg and rotating the body is risky.
* Don’t flex the hip suddenly or above 90 degrees, such as by sitting in a low chair, sitting down too fast, crouching or leaning forward quickly to the feet.
* Inform a doctor if an infection develops in an area such as the teeth, bladder or chest, as these can track to a new joint.
Jonathan Blood Smyth, editor of the Physiotherapy Site, writes articles about Physiotherapist, back pain, orthopaedic conditions, neck pain, injury management and physiotherapists in Edinburgh. Jonathan is a superintendant physiotherapist at an NHS hospital in the South-West of the UK.