MANTIS is a NIHR Health Technology Assessment Trial in response to the commissioned call "Treatment of avascular necrosis of the femoral head"
HTA ref: 15/39/06
Managing Avascular Necrosis Treatments : An Interventional Study
Avascular necrosis of the hip is an uncommon but devastating condition that typically affects younger people. It happens when the bone of the hip joint dies. In its early stages people often feel pain and this is often followed by a rapid collapse of the joint. This leads to severe immobility and suffering in
over half of those affected. In younger patients, this means that they can often not walk comfortably, have sleep disturbance and cannot work. Young people with AVN can often feel socially isolated, given that their activity often limits the amount they can do with friends.
The early phase of treatment usually involves asking the patient to use crutches in the hope that taking the weight off the hip will prevent it collapsing. This is only effective in 15% of patients, however. Joint preserving operations are also used, but often fail.
All too often, many patients will become so immobile that the only cure for their pain will be hip replacement. This happens in three-quarters of patients. Although this is an effective treatment, it is a large operation, which only lasts for 10 to 20 years. Also patients who receive joint replacements for
AVN are at a much higher risk of needing further surgery, having dislocations and having infection postoperatively. At present there is little evidence for an effective drug treatment for preventing AVN.
To do this we will select patients who have AVN at an early stage. We will then ask them to be part of a randomized control trial where they will receive either a drug known as a bisphosphonate, or a placebo (dummy pill) in addition to standard treatments (such as pain killers and physiotherapy) for 1
year. This treatment is simple and safe. As AVN is a relatively uncommon condition, our aim is to recruit a total of 280 patients from 20 or so hospitals around the country. The first part of the trial will include a ‘pilot’ phase, where we will find out whether we can recruit the number of patients required
within a reasonable time period. This is vital, as our initial investigations show that the way in which patients with AVN are sent to hospital can vary a lot. The pilot phase will enable us to determine the best way to recruit patients from as many centres as possible. It will also let us know how often
patients will agree to be part of the trial. If the pilot is successful, then we would like to follow most patients for 3 years. This 3 years will include 1 year of treatment followed by another 2 years of observation, to see if the bisphosphonate drug makes their pain better.