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Treatment of Early Osteoarthritis...

Medico Legal

Treatment of Early Osteoarthritis. What Can We Do Before Total Knee Replacement?

Osteoarthritis (Dengenerative arthritis,Wear and tear arthritis) is extremely common. With increased activity and therefore trauma it is becoming much more common at a younger age. This raises considerations which depend on possible treatment at these earlier ages.

Total Knee Replacement (and other joint replacements) is a good option but not perfect, for instance 10% still complain of pain after it. As the life of a replacement is 10-15 years and this is the same for any subsequent revision if you start out with a replacement at 30 then you rapidly run out of options. By 70 you would have had 3 revisions and no more would be effective.

This coupled with the fact that the pain felt by patients may not correlate at all with any Xray changes then avoiding major surgery early on would seem to be a good plan. The decision to go for major surgery is a decision for a patient, the surgeon’s job is to dissuade him from that decision in the early stages.

Symptoms of OA can be minimal without causing too much distress and a sudden activity such as playing a very hilly golf course or running a marathon can make the symptoms so much worse. I actually arranged a MRI scan for myself after a particularly painful round! In that particular instance a short course of anti-inflammatory drugs would be wise and helpful. Such drugs taken long term should be avoided because of side effects such as bleeding. I know golfers who always take anti-inflammatories before their round but this is not advisable.

Early arthritis is defined as pain with little to show for it. The status of the meniscus and the surface of the joint and the arthroscopic areas of deranged surface cartilage needed to be considered but are likely to be minor. No reasonable surgeon would perform a TKR in this situation.

A number of conservative treatments have been suggested. Interestingly they all have a 50% success rate.

Quads exercises were shown in a paper from Nottingham to be highly effective.They were taught in groups of patients so the treatment is also cost-effective.

Glucosamine and chondroitin sulphate tablets had a wide following.Although easy to take and with few side effects it takes 3 months to know whether they had worked. There is little science behind these drugs.

Paracetamol is effective in treating the pain but has no effect on its progression. After this the treatments get more invasive and look at injections. Steroid injections are very commonly used around the joints.Repeat injections are frequently needed but more than three in six months is thought to be unwise. There is a risk of infection and a risk of fat necrosis at the site of injection.Again the success rate is only 50%.

Hylan injections (eg Synvisc) can be helpful.It is important to inject into the joint and not outside which would produce severe pain.This drug is certainly licensed for the knee but so far as I am aware not for other joint such as the hip. I have heard of it being used in the hip with success. Knee braces have become fashionable. They off load the painful arthritic area by loading the knee onto the normal cartilage and jacking open (slightly) the arthritic part of the joint. Such a brace can be helpful and work in approximately 50% of patients.

The leg should always be considered as a whole. Deformity is common and correction can be helpful. If a wedge is placed under the heel this can correct foot deformity which will alter the knee biomechanics and improve symptoms.

If symptoms continue after simple treatments investigations are useful in differentiation from other types of arthritis which are inflammatory or autoimmune such as Rheumatoid or Psoriatic arthritis.The first would be blood counts and particularly C-Reactive Protein (CRP). This is high in inflammatory disease and low otherwise. Treatment of inflammatory arthritis is very different compared to treatment of OA and inflammatory arthritis is much rarer.

Other tests include Xrays preferably under load on standing. In early OA these signs would likely be very subtle and an MRI would be ordered. Again the signs would be subtle.There would be articular cartilage damage and possibly meniscal damage in the knee. There would be similar changes in other joints but I am concentrating on the knee in this editorial.

The next stage is to consider is surgery. In the knee this would be an arthroscopy. This operation is widely performed but the results are variable. There is a detailed paper in the New England Journal of Medicine which says that athroscopy doesn’t work. They compared arthroscopy with a sham operation,imagine that in the USA! This has been repeated. Unfortunately they excluded all patients with mechanical symptoms which most surgeons would expect to find prior the op. Such symptoms would be locking and catching rather than only pain. Such symptoms would be investigated by MRI. However tears of meniscus are very common in early OA. Recent papers have shown that removing a small tear is not effective. Apart from all the normal complications to discus it is important to advise that pain may continue or even be worse after arthroscopy. The quoted success rate of an arthroscopy where there are no mechanical symptoms is 50% only. Making the joint worse is unusual but is devastating to patient and surgeon.

When this happens there is a drive to move onto TKR but this should be avoided particularly as the joint may improve spontaneously and one should wait at least 6 months before any further surgery is contemplated.Rapidly repeated surgery usually gets worse and worse and can be the source of complaint.

Sometimes surgeons advise to have an arthroscopy immediately prior to TKR to see if the TKR is necessary! This should be avoided as if you can’t tell whether a TKR is the best option on the symptoms and Xrays you shouldn’t be operating! There are few instances when such actions would be right. There is another point. Arthroscopy is a clean and sterile operation but TKR is a superclean operation and infection in a TKR is a disaster and difficult to cure. I have never taken such a course of action.

What can be done with a damaged knee with early degenerative arthritis? Is it possible to delay the progression of disease?

The first stage would be an arthroscopy to define the damage. Simple trimming of meniscus and loose articular cartilage will help immediate symptoms but not the long term. The meniscus takes a lot of the load in the joint and removal has been shown over many years to be one of the main causes of arthritis. This is particularly true if the majority of the meniscus has been removed. It is possible, in regional centres, to implant a donated meniscus often together with other procedures. This is in an early stage and is experimental. However where the rest of the knee is in good condition or can be made so then the results can be worthwhile.

More commonly, with the articular cartilage, the defect is small ,and the underlying bone can be drilled.This is called microfacture and the aim is that tissue resembling articular cartilage will grow from the bone. Where the defect is small this will usually relieve symptoms and possibly delay progression.

Bigger defects up to 2 cms can be filled in various ways. Normal cartilage pegs can be taken from healthy parts of the knee and implanted in the defects. This means that areas of the normal parts are denuded of cartilage and these areas need to chosen for the least effect this will have. Thus the defects treated need to be small and few,less than three.

To avoid autotransplantion it is possible to implant an artificial piece of cartilage. This gives a smooth surface and can relieve symptoms but the longterm outcome is currently unknown.

Larger areas can be grafted by making a sheet of cells and placing in the defect. This is called Autologolous Cartilage Implantation. This technique is only approved in certain Regional Centres. It has advanced to a point where an artificial sheet of tissue is placed across the defect and stem cells are injected under the sheet. Tissue grows across the joint,not entirely the same as cartilage tissue but close to the original. This is a better outcome and may well delay progression of the disease. However it can take 2 years to incorporate the graft so recovery is slow and the patient may have to remain non-weightbearing for all this time.

Any cartilage surgery may require nonweightbearing for 6 weeks. Interestingly it is in all such procedures it is important to move the knee as much as possible as this increases the quality of the cartilage which forms. Rehab is long but very necessary.

The final way to replace large areas of articular cartilage is to replace the whole condyle ( one of the large bulbous ends of the femur) with a donated condyle. This is very unusual and usually kept for patients with malignant tumours.

Deformity of the limb is a common precursor of arthritis. This can be inborn, usually bowlegs or knockknees, or can develop following progressive arthritic change in a single part of the joint, usually on the inside of the knee. This means that greater load is place in that area and arthritis is rapidly progressive. By correcting the deformity the load can be spread over the whole knee and both symptoms and arthritis can be reduced. This correction can only be achieved by operation. Consent is vital. The operation may have been performed perfectly but the success rate is only around 70%. Also correction means that the leg will be at least straight or theorectically slightly overcorrected. This is necessary to spread the load over the whole knee rather than have point loading. The appearance of the change of deformity can be very upsetting for the patient particularly if the deformity is bilateral and the arthritis in only one leg! Skirts and shorts can be a problem and the resulting shape needs detailed explanation pre-surgery. This operation can be carried out a number of ways and the correction held by all the usual orthopaedic techniques. Healing can take 6 months. Nerve and arterial damage is uncommon but more likely with this type of operation than others. Patients can be disappointed with the result and one of my patients demanded a TKR soon after I did the osteotomy although the result looked perfect and the cartilage seemed to be improved. Most will however progress still and in many years and require conversion to a TKR. This has been reported as being difficult or easy depending who you read. It still remains that an early osteotomy when the patient is young followed by a TKR many years later is a good option.

Many patients have TKR’s and some are very disappointed, usually from continuing pain. This can be associated with patients who have major pain and little Xray change. Patients when they are disappointed after TKR argue that they should have been given more conservative treatment. Its useful to know what is available in that area. Given the shorterm benefits of non-operative treatsment one wonders whether this would have made any difference. The rapid follow-on of arthroscopy on arthroscopy within months of each one results in a very disappointed patient with no relief and probably a worse knee. This is often a cause of complaint leading to action.

Clearly consent is very important. This would need to consider the usual complications (infection, DVT, PE) and failure and a full explanation of technique and possible outcome. The outcome needs to be fully explained and written down in a medical note as well as on a consent form. Osteotomy can be a particularly troublesome when the patient notices a sudden change in shape of his limb and didn’t expect it.

Early arthritis should be treated stage by stage and not immediately by a TKR. It is also an area where there are claimants looking at the courts for redress! By going into all the options in great detail and recording all this the surgeon may be able to protect him/herself. Sometimes suggesting internet sites for patients to visit in order to help the patient’s decision can be most useful. ?