60% of surgical reconstruction for ACL could be avoided: KANON study

Jul 22 2010

Anterior cruciate ligament (ACL) injuries are common injuries to the knee, primarily affecting young people who practise sport and often treated with surgical reconstruction. A research group from Lund University has now shown that 60 per cent of these operations could be avoided, without negatively affecting treatment outcomes.

The research group's study is known as the KANON study and started in 2001. This week the group is publishing its results in the New England Journal of Medicine.

"In our study, patients with acute ACL injuries were randomly divided into two groups for treatment with rehabilitation plus early ACL reconstruction or rehabilitation alone with the possibility of a later operation if this was deemed necessary. After two years only 40 per cent of the latter group needed to have an ACL reconstruction.

"Despite the fact that many of the patients were active sportsmen and women, we found no difference between the treatment groups in terms of knee function, activity level or well-being two years after the injury. Neither did we find any difference in these respects when we compared those who were treated with rehabilitation alone with those who had an early operation", says Richard Frobell, researcher at Lund University, Skåne University Hospital and Helsingborg Hospital.

A total of 121 patients took part in the study, which was carried out in collaboration with Helsingborg Hospital and Skåne University Hospital in Lund. The patients were aged between 18 and 35 and had an acute ACL injury in a previously healthy knee. Professional athletes and those who did not regularly practise sport were excluded from the study. All patients underwent extensive rehabilitation, led by experienced physiotherapists.

Sixty-two patients were selected at random to also undergo surgical reconstruction of the injured ligament within four to six weeks of the injury, and 59 patients were selected at random to initially undergo treatment with rehabilitation alone. All the operations were carried out in accordance with well established methods and by experienced surgeons. The patients were examined on several occasions over two years and gave their own opinions of the status of the injured knee.

"There are almost 10 000 scientific publications addressing the ACL and 50 per cent of these are about surgical treatment. However, none of these studies have shown that surgical reconstruction produces better results than rehabilitation alone. Despite this, we perform 3 000 cruciate ligament reconstructions a year in Sweden", says Stefan Lohmander, professor and consultant at Lund University and Skåne University Hospital. "In the USA there are 200 000 operations of this type, at a cost of USD 3 billion!"

The research group's results have strengthened their conviction that there is no evidence to support the recommendation of ACL reconstruction as a first method of treatment.

Rehabilitation with experienced physiotherapists produces the same results as operation for more than half of the individuals in this patient group and only four out of ten need to be exposed to the risks involved in an operation.

The patients in the study will continue to be examined in order to find out whether the results are the same in the longer term and to see if there is any difference between treatments in terms of the risk of developing osteoarthritis in the knee.