More about joints

I had not intended to continue with the problem of knee pain this week – but by coincidence a paper has just been the published about the results of surgery for one cause of knee pain – torn cartilage (or meniscus).

The torn meniscus

The medial and lateral knee menisci are crescent shaped pads of tough “fibrocartilage” which lie between the femur (thigh bone) and tibia (shin bone). They act as shock absorbers and protect the articular cartilage from wear and tear which the main problem in osteoarthritis of the knee joint.  The menisci may be torn when put under strain.  This is a common injury in young people, mainly during sports involving strain or twisting of the knee – ie football, rugby, basketball, tennis. In older people lesser insults can tear a cartilage which has become weakened by age. Torn menisci are painful and restrict physical activity.

Treatment initially is “wait and see”, resting the joint and taking the various measures which I described last time. Surgery may be thought necessary for severe pain or slow recovery and in the past has been a popular approach. The cartilage can be stitched (often not very successful) or partly removed.

The research I mentioned above has been the analysis of the ten year results of a Finnish trial of surgery compared with “sham” surgery for torn meniscus.. This has found that there is no long-term benefit from surgery – indeed the surgical group were more likely to develop osteoarthritis and to suffer more symptoms and limitation of activity that the sham group. They also had a greater need for further surgical intervention.

Surgery for other joint problems

Reading that article got me to thinking about the benefits of surgery for other joint problems – is it better to weigh in with the knife or to leave well alone and let nature and careful management take the strain? Just how does surgery compare with conservative (non-surgical) management?

Joint replacement is most commonly performed for arthritis of the Hip, the knee and the shoulder – in that order.

The hip

Osteo-arthritis of the hip joint (OA hip) later in life is extremely common. Over the age of 60, about 5% of the population in the UK has OA hip bad enough to cause symptoms and over the age of 85 this rises to 25%. OA hip is about twice as common in women as in men. Hip joint replacement is a very successful operation with a satisfaction rate of about 95% and continued good function at ten years in 90%. In randomised controlled trials, patients who received a hip replacement report significantly greater improvements in pain and function compared to those in the exercise group. In these trials, approximately 30% of patients assigned to the conservative group eventually chose to have surgery within one year. 

The knee

Osteo-arthritis of the knee joint (OA knee) later in life is also extremely common. Over the age of 60 about 20% of the population in the UK has OA knee bad enough to cause symptoms and over the age of 85 this rises to about 35% in men and 47% in women. Surgical knee replacement is also effective but results are less satisfactory than for hip joint replacement. Controlled trials of surgery compared with conservative treatment show significant benefits for the surgical group but a moderately high risk of complications such as persisting joint stiffness and blood clots. Recovery is much slower than for hip joint replacement and long-lasting post operative pain is not uncommon. About two thirds of patients assigned to conservative treatment are still coping without surgery after two years.  Between 5 and 10% of patients following knee replacement need revision surgery within the following ten years.

The shoulder

Arthritis of the shoulder joint is much less common than for hips and knees – because the shoulder is not a weight bearing joint. The rate of shoulder replacement surgery is  less that 10% of the rate for hip replacement. Replacement of the shoulder joint is usually recommended only for the management of continuing pain – often defined as causing sleep disturbance and other symptoms for at least a year. Controlled trials of surgery compared with conservative treatment show only small advantages for joint replacement. At one year the satisfaction rate for surgery is around 95% but for conservative treatment it may be between 75 and 95%. In my own experience, most severe shoulder pain resolves or improves significantly within 18 months.

So when it comes to surgery for arthritis, the message is:

1. Hip – thumbs up.
2. Knee – mostly thumbs up.
3. Shoulder – sometimes maybe

But each case is different – this is just a rough guide.