Third-Generation Ceramic-on-Ceramic Total Hip Arthroplasty in Patients with Osteonecrosis of the Femoral Head

Modular femoral heads have been used successfully since the mid-1980s in total hip arthroplasty. The use of metallic modular junctions presents a unique set of advantages and problems for use in total hip arthroplasty (THA). The separation of the head from the stem by a Morse taper has provided many benefits on the precision and balancing the reconstructed joint. Historically few complications have been reported for the modular Morse taper connection between the femoral head and trunnion of the stem in metal-on-polyethylene bearings. However, the risks or concerns are a little harder to identify and deal with. Certainly corrosion, and fatigue failure are the two most prevalent concerns but now the specifics of fretting wear and corrosive wear increasing particulate debris and the potential biological response is having an impact on the design and potential longevity of the reconstructed hip. This paper is dealing with a simpler consequence of head/stem modularity. Modular head mismatch to the socket bearing articulation.Two patients by two different surgeons at two different hospitals underwent cementless THA. Both patients were female and both presented with degenerative changes to the hip articulation. Both patients underwent hip replacement via a direct anterior approach using a standard hemispherical porous coated shell. One patient had a ceramic on ceramic bearing and the other had a ceramic head on a polyethylene liner. Both patients had a 32 mm inside diameter liner implanted and both had a 36 mm ceramic femoral head. The ceramic on ceramic mismatch was not recognized until the second office visit at eight weeks. The ceramic poly mismatch was not recognized until first office visit at six weeks. Both underwent correction surgery.These two cases demonstrate human mistakes can be made and steps need to be established to prevent future mistakes of this nature.

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Fatal Cobalt Toxicity after a Non-Metal-on-Metal Total Hip Arthroplasty

Case Reports in Orthopedics ◽

10.1155/2017/9123684 ◽

2017 ◽

Vol 2017 ◽

pp. 1-5 ◽

Cited By ~ 7

Author(s):

Rinne M. Peters ◽

Pax Willemse ◽

Paul C. Rijk ◽

Mels Hoogendoorn ◽

Wierd P. Zijlstra

Keyword(s):

Femoral Head ◽

Total Hip Arthroplasty ◽

Hip Arthroplasty ◽

Hip Prosthesis ◽

X Rays ◽

Total Hip ◽

Metal On Metal ◽

Metal Wear ◽

Cobalt Toxicity ◽

Ceramic On Ceramic

This case illustrates the potential for systemic cobalt toxicity in non-metal-on-metal bearings and its potentially devastating consequences. We present a 71-year-old male with grinding sensations in his right hip following ceramic-on-ceramic total hip arthroplasty (THA). After diagnosing a fractured ceramic liner, the hip prosthesis was revised into a metal-on-polyethylene bearing. At one year postoperatively, X-rays and MARS-MRI showed a fixed reversed hybrid THA, with periarticular densities, flattening of the femoral head component, and a pattern of periarticular metal wear debris and pseudotumor formation. Before revision could take place, the patient was admitted with the clinical picture of systemic cobalt toxicity, supported by excessively high serum cobalt and chromium levels, and ultimately died. At autopsy dilated cardiomyopathy as cause of death was hypothesized. A third body wear reaction between ceramic remnants and the metal femoral head very likely led to excessive metal wear, which contributed systemic cobalt toxicity leading to neurotoxicity and heart failure. This case emphasizes that fractured ceramic-on-ceramic bearings should be revised to ceramic-on-ceramic or ceramic-on-polyethylene bearings, but not to metal-on-polyethylene bearings. We aim to increase awareness among orthopedic surgeons for clinical clues for systemic cobalt intoxication, even when there is no metal-on-metal bearing surface.

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