HAMPSHIRE scientists are helping to develop a computer model of a hand which could improve joint surgery for those who suffer arthritis in their fingers.

Currently, surgery to replace the proximal interphalangeal (PIP) joint – the second joint in the finger from the finger tip – is not as reliable or predictable as surgery to replace the much larger hip or knee.

Surgery on the joint can reduce pain but the range of movement does not improve and, in some cases, the joint can dislocate, stiffen or wear out.

Professor David Warwick, a consultant hand surgeon at University Hospital Southampton NHS Foundation Trust (UHS) and study lead, said: “Initially, we can try one or two steroid injections and, if unsuccessful, surgery, which includes either stiffening the joint, known as fusion, or replacement using artificial spacers made of metal or plastic.”

Now, however, Prof Warwick and consultant radiologist Dr Leonard King at UHS and engineering experts at the University of Southampton are using data taken from CT and MRI scans, together with motion-tracking technology, to build a computerised model of the PIP joint.

A team at the University of Southampton have applied sophisticated methods developed in aerospace engineering to correlate the data from the scans and the motion-capture.

As part of the study the team will also collect data from patients before and after joint replacement.

Prof Warwick said: “Although most people are pleased with pain relief following surgery, their range of movement in the fingers does not improve and, in many cases, worsens – in which case the intervention is disappointing.

“One of the main reasons for this is that when the joint is diseased, it is technically very difficult to get the artificial joint components to fit precisely with the ligaments and tendons which surround the joint and, to improve that, we need to obtain more information.”

He added: “Then we can design better surgical techniques and better joint

replacements to help patients in the future, so we are

extremely excited about the possibilities this work presents.”