ips-aiims

Hip Replacement Timing – Why Delaying May Be the Wrong Choice

My world was split into two. With medication I was pretty well pain-free but unable to concentrate or focus on anything at all. Without it I was in serious pain and my mobility was so reduced that I could barely manage stairs let alone leave the house. Diagnosis - severe osteoarthritis. My life had become focused on my hip and the prospect of surgery.

A hip replacement at 52? No! Surely I was too young. I asked my medical friends, who were unanimous in their answers; "delay having a hip replacement for as long as possible". Okay, I thought stoically, I'll hang on. But for how long? How would I know when I'd reached "as long as possible"? How could I factor in the length of time I'd be spending on a waiting list? How was I going to function until then? And was waiting really the right answer? I entered "hip replacement timing" into Google and started reading.

The first thing I learnt was that all weight bearing implants have a finite life. As the two surfaces rub together they shed minute bits of debris. This debris sets up a reaction in the body which loosens the tight fitting implant. A loose implant is a painful implant. Sooner or later it will need to be replaced.

Wear is not just associated with the length of time we have the implant for, it's also about what we do with it. The more active the patient is the greater the rate of wear and young people tend to be more active than their elders. From my point of view one of my desired outcomes from surgery was to get back to an active life. Maybe a bit more subdued than before (no more rock climbing) but still one where I challenged myself physically from time to time.

I learnt also that weight plays a key role in how quickly a weight bearing joint, such as a hip, lasts. Heavier patients wear out their hips faster than lighter ones. This is true for both the original joint and its replacement. Students of mechanical engineering will understand that 1kg of body weight puts approximately 4kg of pressure on a hip joint.

But did any of this really matter? If a hip replacement is a fairly straightforward, routine operation surely they could just change my implant once it wore out? Sadly that isn't the case.

Revision surgery involves taking out the old implant and replacing it with a new one and is considerably more complex. Second time around (let alone third) there is less bone stock to work with and the tissues surrounding the joint, and holding it together, have lost much of their flexibility. Without that flexibility it is harder to align the new implant optimally and correct alignment is crucial to reduce the rate of wear.

There is also a higher chance of a serious post-operative complications following revision work. These are nasty. They include painful dislocation ( a trip to A&E), infections (possibly necessitating the removal of the new implant to clean out the infection) and deep vein thrombosis (potentially fatal!).

The case seemed to be made - delay surgery - let one implant last a life time.

I was convinced. I was convinced for all of 10 minutes which is when I started to think about what that would mean for me. Years more serious pain and heavy duty medication and an ever dwindling life both inside and outside the home.

I started looking for the other side of the argument. Might the new generation of implants come to my rescue?

With traditional implants the hip side of the replacement joint was made of polyethylene, which wears out relatively quickly. Replacing this to give a metal-on-metal implant worked well and extended the life span of the new joint. Better yet was ceramic-on-ceramic - where both sides of the joint are made from a type of metal oxide known as ceramic. This has a very low rate of wear and unlike its metal-on-metal counterparts isn't associated with potentially hazardous metal ion debris. This form of ceramic is the 2nd hardest substance on the planet - the hardest being diamond. Somehow I doubted that would be available on the NHS. Still 2nd hardest sounded good. How long would that last?

Well the jury is still out on that question, mainly because these new prostheses are still evolving and sufficient time hasn't yet gone by to evaluate their wear rate. It is hoped that they'll last between 25-30 years - about double the life of a traditional implant. A quick calculation and I realised I'd only need one more (unless I was heading for a Guinness Book of Records type of life span).

I was already beginning to swing to the sooner rather than later approach when I found some information discussing the physiological problems associated with delaying surgery. Medics have always acknowledged that delaying surgery meant the patient would have to endure increasing pain and lack of mobility but the approach seemed to be it just had to be endured. Now the consequences of long-term severe pain and limited mobility are being recognised.

Whilst waiting for surgery my hip joint would continue to wear away increasing both the amount of pain I experienced and the need for very strong medication. Furthermore this wear might also gradually deform the joint itself and one consequence of that may be that options for less invasive surgery, such as hip resurfacing, were lost.

But it's not just the affected leg that is being damaged. As the "bad" leg become less able to weight bear the "good" leg must take on more of the work. The danger here is that the additional stress on the "good" leg's hip and knee joints will hasten their decline and may even result in further joint replacement work.

And it didn't stop there. All this pain and decreased mobility would result in weight gain, loss of muscle mass, a deterioration in the quality of life and an inability to carry out activities of daily living such as shopping and socialising. It sounded like a recipe for depression as well.

A survey of younger patients undertaken by hip replacement and recovery.com - a one-stop information shop - showed that almost 30% of younger patients felt they should have had surgery earlier and that delaying surgery had significantly affected their lives. Their most often stated concerns were the loss of quality of life and further damage to their joints. One respondent wrote touchingly about how she had not been able to participate in the lives of her growing family due to pain and immobility.

There is no simple answer as to what is the best time. I believe it is imperative that all hip replacement patients understand the advantages and risks in either going for early surgery or delaying it. Such an understanding will allow an informed discussion with the surgeon. If your surgeon radically disagrees with you and you don't accept his reasoning, then ask to be referred to someone whose views more closely match your own.

Some pointers as to when it might be time for the operation:

When the pain wakes you at night When you are taking opiate based medication daily. When you can't walk a mile or carry a bag of shopping. When you realise you can't look after yourself When you're quality of life is significantly diminished.

So did I wait? Well I tried to put it off a bit. I called my consultant who explained that I was already practically bone-on-bone and the maximum I could hold out for was two years. That, we agreed, wouldn't be worth the pain.

I am now 13 weeks post-op and pretty well pain-free. Yesterday I ran up the stairs. I've started going out - shopping and socially. I've got a life again. I love my new hip.