Symposium: Papers Presented at the 2009 Closed Meeting of the International Hip Society 25 articles
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.
Strategies for revising a ceramic-on-ceramic total hip prosthesis are controversial. Some consider reimplantation of a ceramic head on a well-fixed femoral stem inadvisable as it may lead to a fracture of the newly implanted head.
Residual acetabular dysplasia of the hip in most patients can be corrected by periacetabular osteotomy. However, some patients have intraarticular abnormalities causing insufficient coverage, containment or congruency after periacetabular osteotomy, or extraarticular abnormalities that limit either acetabular correction or hip motion. For these patients, we believe an additional proximal femoral osteotomy can improve coverage, containment, congruency and/or motion.
Despite stem subsidence being a major complication of femoral impaction bone grafting in cemented revision hip arthroplasty, few studies have distinguished subsidence at the prosthesis-cement interface from that at the cement-bone interface. It is unknown how technique developments intended to improve the procedure influence stability of the stem.
The treatment of end-stage hip disease in very young patients is controversial, with advocates for nonoperative treatment, hip arthrodesis and replacement procedures. The functional improvements in this group of patients are not well documented and whether the condition for which the surgery is performed influences function.
The sensitivity and specificity to detect periprosthetic infection of the different methods have been questioned, and no single laboratory test accurately detects infection before revision arthroplasty.
Hip resurfacing arthroplasty is a common procedure that improves functional scores and has a reported survivorship between 95% and 98% at 5 years. However, most studies are reported from the pioneering rather than independent centers or have relatively small patient numbers or less than five years followup. Various factors have been implicated in early failure.
Acetabular defects are frequently grafted during revision THA. Previous studies using plain radiographs report high rates of graft incorporation. However, given plain radiographs underestimate osteolysis, it is unclear whether plain radiographs adequately reflect graft fill or incorporation.
Late infection is the second most frequent early complication after total hip arthroplasty (THA) and the most frequent after hemiarthroplasty. Known risk factors for infection after THA include posttraumatic osteoarthritis, previous surgery, chronic liver disease, corticoid therapy, and excessive surgical time. However, risk factors for hemiarthroplasty are not clearly established.
There is emerging evidence that even mild slipped capital femoral epiphysis leads to early articular damage. Therefore, we have begun treating patients with mild slips and signs of impingement with in situ pinning and immediate arthroscopic osteoplasty.
The treatment of recurrent dislocation after total hip arthroplasty remains challenging. Dual mobility sockets have been associated with a low rate of dislocation but it is not known whether they are useful for treating recurrent dislocation.
Impaction bone grafting has been used for acetabular reconstruction in revision surgery. However, most series do not establish differences in survival in revisions with differing severity of bone loss.
The alumina-on-alumina bearing surface, which has a high wear resistance and a good biocompatibility, is widely used in THA but recently has been associated with squeaking. While various authors have reported factors associated with squeaking, they remain poorly understood.
Many studies have reported the factors influencing the progression of collapse and development of osteoarthritis after a transtrochanteric rotational osteotomy. It is not well understood how the healing process of the osteonecrotic area occurs after this procedure.
Although hip arthroplasty reliably relieves pain and improves function, problems have arisen with wear and osteolysis. Highly crosslinked polyethylene has been developed to address this problem although at present there is limited clinical evidence it does so longer term.
Evidence of Reduced Muscle Trauma Through a Minimally Invasive Anterolateral Approach by Means of MRI
Minimally invasive techniques in THA are intended to minimize periarticular muscle trauma. The lateral approach has a risk of partial gluteal insufficiency, while the anterolateral approach carries the risk of damaging the tensor fasciae latae through intermuscular nerve and compression injury.
Total hip arthroplasty (THA) in the presence of developmental dysplasia of the hip (DDH) can be technically challenging. Restoring the anatomic center of hip rotation may require femoral osteotomy. Techniques using cementless components are widely reported but less is known about using cemented components that may be more appropriate with osteopenic bone.
Transtrochanteric Rotational Osteotomy for a Subchondral Insufficiency Fracture of the Femoral Head in Young Adults
While subchondral insufficiency fracture of the femoral head is most frequently seen in elderly patients, this fracture has also been reported in some young individuals.
Little is known about intraarticular pathology following THA prior to the radiographic appearance of osteolysis, primarily due to imaging limitations. MRI has recently been applied to imaging the postarthroplasty hip with the ability to detect periarticular bony and soft tissue pathology; specifically, it is able to detect abnormal synovial patterns and focal bone loss well before the radiographic appearance of osteolysis.
Young patients with degenerative cartilage disease of the hip remain a challenge for the orthopaedic surgeon. Different treatment options are available of which uncemented hips are the most popular owing to long-term concerns about cemented implants. As an alternative, we have used a cemented hip design in combination with bone impaction grafting in patients with acetabular defects.
The direct anterior approach in THA is an intermuscular approach that requires no muscle detachment. However, it is difficult to elevate the proximal femur for access to the femoral canal.
THA performed in patients with cognitive deficits or neuromuscular diseases has been associated with a high postoperative dislocation rate. The constrained liner reportedly provides stability in patients with recurrent dislocation. However, achieving stability could be offset by early loosening when used in patients with neurologic diseases.