A prospective study of a ceramic-on-metal bearing in total hip arthroplasty

Abstract

We prospectively assessed the efficacy of a ceramic-on-metal (CoM) hip bearing with uncemented acetabular and femoral components in which cobalt-chrome acetabular liners and alumina ceramic heads were used. The cohort comprised 94 total hip replacements (THRs) in 83 patients (38 women and 45 men) with a mean age of 58 years (42 to 70). Minimum follow-up was two years. All patients had pre- and post-operative assessment using the Western Ontario and McMaster Universities osteoarthritis index (WOMAC), Oxford hip score and Short-Form 12 scores. All showed a statistically significant improvement from three months post-operatively onwards (all p < 0.001). After two years whole blood metal ion levels were measured and chromosomal analysis was performed. The levels of all metal ions were elevated except vanadium. Levels of chromium, cobalt, molybdenum and titanium were significantly higher in patients who underwent bilateral THR compared with those undergoing unilateral THR (p < 0.001). Chromosomal analysis demonstrated both structural and aneuploidy mutations. There were significantly more breaks and losses than in the normal population (p < 0.001). There was no significant difference in chromosomal aberration between those undergoing unilateral and bilateral procedures (all analyses p ≥ 0.62). The use of a CoM THR is effective clinically in the short-term, with no concerns, but the significance of high metal ion levels and chromosomal aberrations in the long-term remains unclear.

Early Results of Our International, Multicenter, Multisurgeon, Double-Blinded, Prospective, Randomized, Controlled Trial Comparing Metal-on-Metal With Ceramic-on-Metal in Total Hip Arthroplasty

“…However, one study suggested that any increase in metal ions was comparable between CoM and MoM groups at 1 year, perhaps explained by a bedding in phase [8] and no conclusion on clinical application could be made. There are reports of uncertainty in the performance of CoM bearings with regard to metal ion levels [9,10], which our study supports, with increasing Cr levels at 5 years despite a promising initial response up to 3 years. We are not aware of any other study following up a CoM bearing at longer term.…”

Adverse reaction to metal debris in a patient with acetabular shell loosening 8 years after ceramic-on-metal total hip arthroplasty

“…Algorithms designed to help surgeons navigate clinical encounters with painful MoM hips may or may not be applicable to CoM and MoC hips 4 , 5 . Elevated serum metal ion levels after CoM THA has previously been reported and is associated with an increase in chromosomal breaks, aneuploidy in peripheral lymphocytes, and systemic symptoms including vision changes and hearing loss 12 , 13 , 16 , 18 .…”

“…Initial enthusiasm for CoM and MoC hips originated from industry-sponsored hip simulator analyses 9 , 10 , 11 and a limited number of in vivo clinical trials with short-term follow-up 11 , 12 , 13 . Despite previous reports of CoM and MoC bearing surfaces possessing good functional outcomes at short-term follow up, elevations in cobalt and chromium levels were observed that often paralleled levels seen in patients with MoM hips 11 , 12 , 13 . The significance of elevated metal ion levels was underappreciated at the time, and it is estimated that the CoM bearing surface combination alone was used in >10,000 THAs [14] .…”

Clinical and pathogenetic role of endogenous and exogenous metals in gonocoxarthrosis, contained in the prosthetic knee and hip joints

“…Для ендопротезування колінних та кульшових суглобів при термінальних стадіях гонартрозу й коксартрозу зазвичай використовуються штучні зчленування, що містять, Co, Cr, Mo, Ti, V та інші метали [9]. H. A. Kazi et al [10] встановили, що після двох років існування в організмі хворих таких ендопротезів тільки рівень V у крові не змінюється, тоді як концентрації інших металів значно зростають. J. Steinberg et al [11] було показано, що несприятливий перебіг ГКА після ендопротезування суглобів штучними зчленуваннями, що містять кобальто-хромовый сплав, супроводжується збільшенням у крові рівнів і Со, і Cr.…”