Clinical Orthopaedics and Related Research ®

A Publication of The Association of Bone and Joint Surgeons ®

Hip 719 articles

Articles

Continued Improved Wear with an Annealed Highly Cross-linked Polyethylene

William N. Capello MD, James A. D’Antonio MD, Rama Ramakrishnan MS, Marybeth Naughton BS

Highly cross-linked polyethylene (HXLPE), created by disrupting the molecular structure of polyethylene, then through the application of heat, encourages creation of new cross-links in the process, resulting in a material with improved wear resistance. The impetuses for this new technology were the unsatisfactory wear properties and subsequent osteolysis of noncross-linked polyethylene. A 72% reduction in wear using highly cross-linked polyethylenes (HXLPE) compared with conventional polyethylene at 5 years was described previously. The longest term followup studies on HXLPE range from 2 to 6 years.

Wear versus Thickness and Other Features of 5-Mrad Crosslinked UHMWPE Acetabular Liners

Fu-Wen Shen PhD, Zhen Lu PhD, Harry A. McKellop PhD

The low wear rates of crosslinked polyethylenes provide the potential to use larger diameters to resist dislocation. However, this requires the use of thinner liners in the acetabular component, with concern that higher contact stresses will increase wear, offsetting the benefits of the crosslinking.

Hip Offset in Total Hip Arthroplasty: Quantitative Measurement with Navigation

Manish Dastane MD, Lawrence D. Dorr MD, Rupesh Tarwala MD, Zhinian Wan MD

Offset in THA correlates to abductor muscle function, wear, and impingement. Femoral offset after THA is not independent of the cup center of rotation (COR) so hip offset, a combination of femoral offset and change in hip COR, becomes the important measurement.

Improving Cup Positioning Using a Mechanical Navigation Instrument

Simon D. Steppacher MD, Jens H. Kowal PhD, Stephen Barry Murphy MD

Although surgical navigation reduces the rate of malpositioned acetabular cups in total hip arthroplasty (THA), its use has not been widely adopted. As a result of our perceived need for simple and efficient methods of navigation, we developed a mechanical navigation device for acetabular cup orientation.

Retrieved Highly Crosslinked UHMWPE Acetabular Liners Have Similar Wear Damage as Conventional UHMWPE

David T. Schroder MD, Natalie H. Kelly BS, Timothy M. Wright PhD, Michael L. Parks MD

Highly crosslinked UHMWPE is associated with increased wear resistance in hip simulator and clinical studies. Laboratory and case studies, however, have described rim fracture in crosslinked acetabular liners. Controversy exists, therefore, on the relative merits of crosslinked liners over conventional liners in terms of wear performance versus resistance to fatigue cracking.

Does a Cemented Cage Improve Revision THA for Severe Acetabular Defects?

Erik Hansen MD, David Shearer MD, MPH, Michael D. Ries MD

Evidence suggests a growing incidence of revision total hip arthroplasty (THA) including a subset with large acetabular defects. Revision THA for severe acetabular bone loss is associated with a relatively high rate of mechanical failure.

Bernese Periacetabular Osteotomy in Males: Is There an Increased Risk of Femoroacetabular Impingement (FAI) After Bernese Periacetabular Osteotomy?

K. Ziebarth MD, J. Balakumar MBBS, FRACS (Orth), S. Domayer MD, Y. J. Kim MD, PhD, M. B. Millis MD

The Bernese periacetabular osteotomy (PAO) is a popular option for treating symptomatic acetabular dysplasia. We noted symptomatic impingement after PAO in several male patients.

CT Reveals a High Incidence of Osseous Abnormalities in Hips with Labral Tears

Mark M. Dolan MD, Benton E. Heyworth MD, Asheesh Bedi MD, Gavin Duke MD, Bryan T. Kelly MD

Acetabular labral tears are being diagnosed with increasing frequency and there is a growing consensus that these tears rarely occur in the absence of osseous abnormalities.

Femoral Insufficiency Fractures Associated with Prolonged Bisphosphonate Therapy

Joseph D. Isaacs MD, Louis Shidiak MD, Ian A. Harris MD, PhD, Zoltan L. Szomor MD, PhD

Emerging evidence has linked the long-term use of bisphosphonates with femoral insufficiency fractures. It has been suggested that the prolonged effect on bone remodeling leads to the accumulation of microfractures and weakening of bone.