Hip 715 articles
Femoral neck fracture in hip resurfacing has been attributed to technical error during femoral head preparation. In the absence of fracture, several radiographic findings have been speculated to increase the risk of femoral component failure.
High rates of heterotopic ossification have been associated with hip resurfacing as compared to THA. Bone debris from femoral head reamings is cited as one of the risk factors linked to increased rates of heterotopic ossification.
Dislocation remains a serious complication in hip arthroplasty. Resurfacing proponents tout anatomic femoral head restoration as an advantage over total hip arthroplasty. However, advances in bearings have expanded prosthetic head options from traditional sizes of 22, 26, 28, and 32 mm to diameters as large as 60 mm. Large heads reportedly enhance stability owing to increased range of motion before impingement and increased jump distance to subluxation. Available larger diameter material combinations include metal- or ceramic-on-highly crosslinked polyethylene and metal-on-metal, each with distinct advantages and disadvantages.
While acetabular structural allografts provide an important alternative for reconstructions, concerns remain with long-term graft resorption, collapse, and failure. Midterm studies of minor column (shelf) allograft suggest reasonable survival but long-term survival is unknown.
Pelvic radiographs are helpful in assessing limb-length discrepancy (LLD) before and after THA but are subject to variation. Different methods are used to determine LLDs. As a pelvic reference, both ischial tuberosities and the teardrops are used, and as a femoral reference, the lesser trochanter and center of the femoral head are used.
Femoroacetabular impingement is recognized as a cause of hip pain in young adults and as a precursor to osteoarthritis although many questions persist regarding its management. One in particular is when to resect a pincer lesion and how much to resect. Instability can result from overresection and persistent impingement can result from underresection.
Alternative bearing materials in THA have been developed to reduce the incidence of osteolysis. Alumina-on-alumina bearings exhibit extremely low wear rates in vitro, but concerns exist regarding component impingement with the potential for dislocation and the occurrence of noise.
Incidence of Postthrombotic Syndrome in Patients Undergoing Primary Total Hip Arthroplasty for Osteoarthritis
Postthrombotic syndrome (PTS) is a chronic condition in the lower extremity that develops after deep vein thrombosis (DVT). The incidence of PTS after total hip arthroplasty (THA) is not well established.
Polyethylene wear may be affected by the type of polyethylene resin, manufacturing technique, degree of thermal stabilization, and sterilization technique.
Perivascular lymphocytic infiltration (PVLI) suggests an adaptive immune response. Metal hypersensitivity after THA is presumed associated with idiopathic pain and aseptic loosening, but its incidence and relationship to metallic wear leading to revision are unclear as are its presence and relevance in non-metal-on-metal arthroplasty.