Ceramic bearing surfaces are increasingly used for total hip replacement, notwithstanding that concern is still related to ceramic brittleness and its possible mechanical failure. The aim of this systematic review is to answer three questions: (1) Are there risk factors for ceramic component fracture following total hip replacement? (2) Is it possible to perform an early diagnosis of ceramic component failure before catastrophic fracture occurs? (3) Is it possible to draw guidelines for revision surgery after ceramic components failure? A PubMed and Google Scholar search was performed and reference citations from publications identified in the literature search were reviewed. The use of 28 mm short-neck femoral head carries an increased risk of fracture. Acetabular component malposition might increase the risk of ceramic liner fractures. Synovial fluid microanalysis and CT scan are promising in early diagnosis of ceramic head and liner failure. Early revision is suggested in case of component failure; no consensus exists about the better coupling for revision surgery. Ceramic brittleness remains a major concern. Due to the increased number of ceramic on ceramic implants, more revision surgeries and reports on ceramic components failure are expected in the future. An algorithm of diagnosis and treatment for ceramic hip failure is proposed.

No abstract

The restoration of the hip centre of rotation in an anatomical position is considered to be relevant for total hip prosthesis survival. When the cup is implanted with a high centre of rotation, the lever arm of the abductor muscles is decreased, causing higher joint-reaction forces. Modular stems with varying lengths and geometries can be used to balance soft tissues, and ceramic bearing surfaces can be used to reduce the wear rate. Forty-four hip replacements performed with a high hip centre of rotation were matched with 44 performed with an anatomical centre of rotation. In all cases the preoperative diagnosis was dysplasia of the hip (DDH) and cementless modular neck prostheses with ceramic bearing surfaces were used. At nine years follow-up the mean Harris hip and WOMAC scores were not statistically different. All stems and cups were stable; the femoral offset was no different between the two groups (p = 0.4) as leg-length discrepancy (p = 0.25).

Despite the high rate of neurological complications, possibly related to excessive limb lengthening or inadequate soft-tissue release, total hip replacement can be considered a feasible option for patients with Legg-Calvé-Perthes disease. Careful preoperative planning is advisable in order to overcome the technical pitfalls related to the abnormal proximal femoral and acetabular anatomy of these patients.

Systematic review, Level II.

No abstract

The aim of this study was to detect risk factors for ceramic liner fractures. 26 cementless ceramic on ceramic (COC) total hip arthroplasties (THA) revised because of ceramic liner fracture in 24 patients were compared with 49 well-functioning COC THA performed in 49 patients. Demographic parameters, type of ceramic of the liner, size and neck length of the femoral head, cup abduction angle, cup anteversion, femoral off-set, height of the centre of rotation and the incidence of noisy hips during follow-up examination were compared. A greater number of cups placed outside the optimal range of cup anteversion was found in the fracture group (p = 0.03). An audible noise was detected in 21 cases (80.7%) in the fracture group and in 3 cases (6.1%) in the non-fracture group (p = 0.001). A cup anteversion angle out of the optimal range of 15˚+/-10˚ was found to be a risk factor for ceramic liner fracture and the presence of a noisy hip frequently anticipated the failure. In our opinion neck-to-cup impingement with head subluxation and edge loading on the liner rim could have an important role in the onset of noise and subsequent liner failure, and cup malposition contributes to this mechanism of failure.

We recommend total hip replacement for patients who suffer from slipped capital femoral epiphysis because of the satisfactory survival, low complication rate, and the possibility of restoring leg length.