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Squeaking in Ceramic-on-Ceramic Total Hip Replacements

 Todd V. Swanson, MD

While the wear rate with ceramic-on-ceramic total hip replacements is negligible and other problems (including fracture) extremely rare with the use of well-designed components and accurate surgical technique, squeaking in total hip replacements has recently become an issue. Squeaking in total hip replacements is thought to be caused by roughening of the ceramic surface of one or both components, or the presence of 3rd body debris in the space between the ball and socket.

Any impingement between the neck of the femoral component and the ceramic liner of the socket can generate particles of ceramic and/or metal that may lead to squeaking. Partial shucking of the head in and out of the socket may also cause damage to the ceramic surfaces stripe wear. Avoiding these problems is highly dependent on accurately positioning the acetabular and femoral components.

Recently, it has been noted by several authors, including myself, that a particular design of ceramic liner (where the ceramic is protected from chipping by a metal ring which extends past the ceramic) used with a specific femoral component manufactured by the same company has lead to an extremely high risk of squeaking. The squeaking likely occurs due to impingement of the metal femoral neck against the protective metal ring, generating metal debris which enters the interface between the ball and socket and causes a vibration that we hear as a squeak. In my practice, the incidence of significant squeaking in designs without the protective ring is less than 1/2% while the incidence of squeaking in a small group of ceramic hips with this protective ring is >10%, a 20-fold increase. Therefore, many surgeons, including myself, have quit using this acetabular component design.

Ceramic hips require very precise placement of the components to prevent impingement between the femoral and acetabular components. However, if done well, a ceramic hip should wear extremely well without chipping, breakage, or squeaking, and also without the theoretical risks that metal-on-metal hips carry.

Because implant positioning is absolutely critical to the success of a ceramic-on-ceramic total hip replacement, be sure to ask your surgeon how much experience he has with ceramic-on-ceramic hip replacements. Done well, these hips may last your lifetime, even if you are young and active.

Additional reading on squeaking ceramic hips:
» Influences of Prosthetic Design on Squeaking after Ceramic-on-Ceramic Total Hip Arthroplasty AAOS 2009 Poster
» Influences of Prosthetic Design on Squeaking after Ceramic-on-Ceramic Total Hip Arthroplasty AAOS 2009 Handout
» “The Squeaking Hip: A Cause for Concern-Disagrees.” Yang CC et al Orthopedics. 2007 Sep;30(9):739-42
» “Squeaking in a Ceramic on Ceramic Total Hip” Eickman TH et al Proceedings of the 8th BIOLOX Symposium 2003.
» “Squeaking in Ceramic-on-Ceramic Hips; Incidence, Causes and Solutions.” Toole, G. et al 2008.

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