Squeaking, a high-pitch screeching sound, is a complication of ceramic-on-ceramic articulation in THA.
- Pathologic squeaking– squeaking that occurs in every step,
-associated with anterosuperior edge loading secondary to excessive inclination & anteversion of the acetabular component,
-more concern for pt. (anxiety, embarrassment), seeks further surgical intervention.
- Benign squeaking– squeaking that happens only with deep hip ﬂexion,
– associated with posterior edge loading and
-usually can be improved with pt. education(to avoid specifc positions & by reassuring the patient)
Cause of Squeaking- by loss of ﬂuid film lubrication due to- a)edge loading (a result of either component malpositioning or, a well-positioned component at the extremes of motion); b)ceramic debris particles; c)damage to the bearing surface.
The combination of higher surface friction & a metallic stem, that can resonate, can produce an audible sound.
It is suggested by some to have an association between squeaking & higher wear rate & by others with ceramic fractures.
Assessment of Squeaking: by CT analysis- evaluate component positioning & rule out any possible ceramic fractures.
An open discussion regarding bearing selection with the Pt is advocated before performing THA is performed; to reduce litigation against surgeons if bearing related complications occur.