A high pitched sound that can be heard with hip movement after a hip replacement is not uncommon. The problem was first reported back in the 1950s. Some design changes were made and the problem seemed to correct itself.
Then ceramic-on-ceramic implants became popular again in the 1970s. The squeaking problem developed again. Sound studies were done and joint replacement engineers found that hard-on-hard implants (e.g., metal-on-metal or ceramic-on-ceramic) made the most noise.
The newer implants made of titanium alloy are more flexible and less stiff. This feature could increase the vibrational force that creates friction and squeaking. Other contributing factors include loss of fluid lubricating the hip, tiny particles of metal or other debris from the implant, or damage to the surface of the implant.
When surgeons remove squeaking hips, they often find a stripe along the implant where stress and friction have worn it down. Since squeaking occurs most often with hip flexion (bending, walking), the location of the stripe suggests edge-loading wear. Edge-loading refers to the upper/outer (superolateral) edge of the liner of the socket coming in contact with the upper (superior) surface of the femoral head.
Squeaking doesn’t develop until the patient has had the implant for quite a while (six months or more). The time delay is consistent with the stripe wear just described as well as the loss of lubricating fluid. Likewise, metal debris caused by impingement (one part of the implant is pinching against another) accumulates over time.
It’s probably time for you to make a follow-up appointment with your surgeon to find out what’s going on. Treatment usually begins with avoidance of all movements that make the hip squeak. But you may be a candidate for some simple revisions of the implant and/or hip.