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 .
Patient relevant outcome 7 years after total hip replacement for OA - a prospective study
Background To investigate prospect ively the patient-relevant outcome 7 years after  total hip replacement ( THR ) for osteoarthritis ( OA ) . Methods 219 consecutive patients ( 120 women ) with primary OA , mean age 71 ( range 50 - 92 ) were assigned for THR .  They were examined preoperatively , at 3 , 6 , 12 months , and at 4 , 5 and 7 years postoperatively with the self-administered question naires SF-36 and WOMAC . Supplementary questions regarding postoperative complications , general co-morbidity , social circumstances and patient satisfaction were asked at the three last follow-ups . A reference group , 117 subjects ( 67 women ) , mean age 72 ( range 52 - 92 ) without hip complaints were recruited from the community and investigated at the same times . Results 151/170 ( 89 % ) of the patients and 65/74 ( 88 % ) of the reference group participated at the 7 year follow-up . The best postoperative result was reported one year postoperatively . At the 7 year follow up there was a significant difference between the patients and controls in SF-36 physical function ( PF ) and role physical ( RP ) but not of WOMAC function . There was no difference in frequency of co-morbid conditions between those operated and the reference group , but those operated were in greater need of walking aid ( 46 % vs. 8 % p < 0.0001 ) and reported more regional and widespread pain ( 68 % vs. 53 % p < 0.05 ) . Conclusion This study shows that in an unselected cohort the patients experience a similar health-related quality of life as a reference group of a similar age and sex structure 7 years after THR except for general physical function where the patients score worse
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 .