Abstract
Ceramic-on-ceramic (COC) total hip arthroplasties (THAs) with large heads (>36 mm) were introduced to reduce dislocation rates and restore the hip anatomy as closely as possible to the native one. To date, the literature is scarce and fragmented; a review is desirable to point out the outcomes and the possible specific complications (noise, groin pain, and taperosis). A systematic review about large-diameter COC THAs was conducted according to the PRISMA guidelines. The PubMed and Cochrane databases were searched using the terms "large", "big", "head", "hip", and "ceramic." The methodological quality of the papers was assessed using the MINORS (Methodological Index for Nonrandomized Studies) score. Seven papers (level of evidence: 5 case series and 2 case-control studies) met the inclusion criteria. Clinical outcomes were excellent in >90% of the patients. Groin pain was reported in only 1 article (7%). Radiological outcomes were positive. Minimal revision rates (<2%) were reported at short- to mid-term follow-ups. Dislocation rates were usually <1%. No bearing surfaces failed. No case of trunnionitis was reported. Noise occurred in up to 30% of the patients, mostly squeaking. The noise did not influence clinical outcomes or patients' satisfaction. Noise was inconstantly associated with component positioning, younger age, high articular excursions, and larger sizes. Large-diameter heads in COC THAs (≥40 mm) showed promising clinical and radiological outcomes with minimal revision rates. Noise is a cause of concern and should be carefully evaluated at longer follow-ups and in larger, prospective, and specifically designed case series.