Conclusions Revisions and reoperations are more frequent and occur earlier with metal-on-metal hip resurfacing , except when discontinued devices are removed from the analyses .
Background Metal-on-metal hip resurfacing was developed for younger , active patients as an alternative to THA , but it remains controversial .
Study heterogeneity , inconsistent outcome definitions , and unst and ardized outcome measures challenge our ability to compare arthroplasty outcomes studies .
Questions / purpose sWe asked how early revisions or reoperations ( within 5 years of surgery ) and overall revisions , adverse events , and postoperative component malalignment compare among studies of metal-on-metal hip resurfacing with THA  among patients with hip osteoarthritis .
Secondarily , we compared the revision frequency identified in the systematic review with revisions reported in four major joint replacement registries .
Differences in outcomes of obese women and men undergoing primary total hip arthroplasty.
OBJECTIVE To evaluate the effect of obesity on the incidence of main complications ( infection , dislocation , and revision ) , functional outcome , and patient satisfaction 5 years after primary total hip arthroplasty ( THA )  , and to determine whether results differ between obese women and men . METHODS We conducted a hospital-based prospect i ve cohort study including patients who underwent primary THA ( 2,495 hips ) between 1996 and 2005 . We used rates and rate ratios to compare the incidence of main complications in obese and nonobese patients , and we stratified the data for sex . Functional outcome was measured using the Harris Hip Score and Western Ontario and McMaster Universities Osteoarthritis Index . RESULTS The adjusted incidence rate ratio for infection ( obese versus nonobese ) was 4.4 ( 95 % confidence interval [ 95 % CI ] 1.8 , 10.8 ) . Obesity substantially increased the infection rate in women ( incidence rate ratio comparing obese with nonobese women 16.1 ; 95 % CI 3.4 , 75.7 ) , whereas obesity appeared to have no effect in men ( incidence rate ratio 1.0 ; 95 % CI 0.2 , 5.3 ) . The adjusted incidence rate ratio for dislocation ( obese versus nonobese ) was 2.4 ( 95 % CI 1.4 , 4.2 ) , with a higher rate increase in obese women . A total of 817 patients had a 5-year clinical followup visit . Functional outcome and satisfaction were slightly lower in obese women partly due to higher complication rates . No difference was seen in men . CONCLUSION Primary THA is a successful intervention in obese patients , but physician and patient must be aware of increased complications , particularly in women
Conclusions Revisions and reoperations are more frequent and occur earlier with metal-on-metal hip resurfacing , except when discontinued devices are removed from the analyses .
Background Metal-on-metal hip resurfacing was developed for younger , active patients as an alternative to THA , but it remains controversial .
Study heterogeneity , inconsistent outcome definitions , and unst and ardized outcome measures challenge our ability to compare arthroplasty outcomes studies .
Questions / purpose sWe asked how early revisions or reoperations ( within 5 years of surgery ) and overall revisions , adverse events , and postoperative component malalignment compare among studies of metal-on-metal hip resurfacing with THA  among patients with hip osteoarthritis .
Secondarily , we compared the revision frequency identified in the systematic review with revisions reported in four major joint replacement registries .