When I first started having knee pain many years ago, an orthopedic surgeon told me he thought the problem may have arisen because one of my legs is a fraction of an inch shorter than the other. Such a condition may exist with many people who never notice the difference. However, if you are running marathons, which I was back then, the slight difference in leg length can become noticeable and lead to skeletal pain somewhere.
When someone gets a hip replaced, a similar problem may arise. After the replacement, it is not uncommon for the leg attached to the replaced hip to end up a little longer or shorter than it was before. If the leg-length changes by less than 3/8 of an inch, the body is able to adapt and compensate. However, if the length change is more, posture changes can develop, which can lead to back pain. A team of scientists at the Fraunhofer Institute for Machine Tools and Forming Technology based out of Chemnitz, Germany, may have a solution to the problem.
The artificial hip developed by the scientists is adjustable. After the hip is surgically inserted into the patient, the surgical team uses a computerized camera system to measure the exact length of the leg. If the length needs to be adjusted, the surgeon can turn a screw which connects the artificial hip’s femoral stem and the ball and socket. Once the length measurement matches the proper length, the implant can be secured and the surgery completed. The adjustable system is in the testing phase, but the scientists are hopeful it will be ready for clinical adoption within two years. In the future, I envision a procedure involving very precise measurements being taken from MRI or CAT scans and then a precision hip replacement will be created using a 3-D printer.