The relationship between the design, position, and articular wear of acetabular components inserted without cement and the development of pelvic osteolysis

Between 1983 and 1987, an acetabular component with a unique chamfered-cylinder design was inserted without cement in 134 hips. With use of this design, initial stability is achieved through a cylindrical interference fit with the peripheral rim of the acetabulum, without the need for pegs, spikes, or screws. At an average of sixty-four months (range, forty to ninety-six months) after implantation, follow-up data were available for 113 hips (ninety-three patients). No component had been revised for loosening or was radiographically loose. However, the prevalence of balloon-like osteolysis of the pelvis was 17 per cent (nineteen hips). This bone loss was generally not associated with pain or other symptoms. Ten of the nineteen hips that were associated with pelvic osteolysis (including six of the nine that were associated with osteolysis of the ilium) had been reconstructed with use of an acetabular component that had no holes in the shell (that is, the shell was completely solid). This finding indicates that, while elimination of holes through the acetabular shell may have advantages, it will not prevent pelvic osteolysis. The osteolysis of the ilium was associated with a lateral opening of the acetabular component of more than 50 degrees (p < 0.0001). All of the hips in this series had insertion of a porous-ingrowth femoral resurfacing component made of titanium alloy. These components are no longer used. Revision of the femoral side due to osteolysis provided a unique opportunity to inspect directly forty-two clinically well functioning acetabular components. All of the polyethylene liners and acetabular shells were found to be rigidly fixed. Inflammatory tissue at the periphery of the implant-bone interface resulted in circumferential resorption of periacetabular bone despite rigid fixation of the component. This is direct evidence that a process of bone resorption similar to that reported at the cement-bone interface of cemented acetabular components can occur at the implant-bone interface of components inserted without cement. At the reoperation, a communication that had led to the pelvic osteolysis was found through areas of bone resorption at the periphery of the implant-bone interface. These areas were essentially cystic and were filled with a mixture of fluid and friable, yellow-tan tissue. It appeared that the osteolytic process had expanded into the soft cancellous bone and marrow while being contained by the denser cortical shell of the pelvic bones.(ABSTRACT TRUNCATED AT 250 WORDS)

Disparities in utilization of outpatient rehabilitative care following hip fracture hospitalization with respect to race and ethnicity

OBJECTIVE

To compare the prevalence of discharge home to self-care after hip fracture hospitalization among the elderly in 3 racial groups: whites, Hispanics, and blacks.

DESIGN

Secondary data analysis.

SETTING

US hospitals.

PARTICIPANTS

Patients (N=34,203) aged 65 and older with Medicare insurance discharged after hip fracture hospitalization between 2001 and 2005.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURE

Discharge home to self-care.

RESULTS

Bivariate analyses showed higher rates of discharge home to self-care among minorities, 16.4% for Hispanics, 8.7% for blacks, and 5.9% for whites. Hispanics had 3-fold higher odds of being discharged home to self-care, and blacks had about 50% higher odds of being discharged home to self-care after adjusting for age, sex, Klabunde's comorbidity index, income, year of admission, type of hip fracture, surgical stabilization procedure, and length of hospital stay.

CONCLUSIONS

The higher rate of discharge home to self-care among minorities underscores the risk of suboptimal outpatient rehabilitative care among minorities with hip fracture.

The impact of race/ethnicity on preoperative time to hip stabilization procedure after hip fracture

BACKGROUND

We sought to examine the preoperative time for hip stabilization procedure among Hispanics, non-Hispanic blacks (blacks) and non-Hispanic whites (whites).

METHODS

This was a secondary data analysis using Medicare claims data. Our analysis included 40,321 patients admitted for hip fracture hospitalization from 2001-2005. Our primary analysis was generalized linear modeling, and our dependent variable was preoperative time. Our independent variable was race/ethnicity (Hispanics, blacks versus whites), and covariates were age, gender, income, type of hip fracture and comorbidities.

RESULTS

Bivariate analyses showed that both Hispanics and blacks experienced a longer preoperative time (P < 0.01). The average (mean) of days to surgery was 1.2 for whites, 1.6 for blacks and 1.7 for Hispanics. The delayed preoperative time among Hispanics and blacks persisted after adjusting for covariates.

CONCLUSIONS

The delayed preoperative time among minorities suggests the need to closely monitor care among minorities with hip fracture to determine how to best address their developing needs.