If you're facing a total hip replacement, you might wonder if the type of implant matters for how long it lasts and what problems you might face. A big review of past studies, looking at over 51,000 hip stems, gives some clues. It found that compared to older 'anatomic' stem designs, newer ones like 'single-taper' and 'single-wedge' were linked to a much lower risk of needing a revision surgery—meaning the implant had to be replaced. For example, the revision rate for anatomic stems was 3.9%, but single-taper and single-wedge stems had relative risks of 0.38 and 0.31, suggesting they might fail less often.
Beyond just lasting longer, these newer stems also seemed to lower the risk of other issues. They were associated with less aseptic loosening (where the implant comes loose without infection), less instability (where the joint dislocates), and fewer fractures around the implant. But it's not all good news: single-taper and taper wedge stems showed a higher relative risk of periprosthetic joint infection, a serious complication, compared to anatomic stems.
This review pooled data from 18 studies between 2015 and 2025, involving patients getting their first hip replacement. It didn't report on safety events like side effects or how many people dropped out, and the follow-up time wasn't specified. Importantly, this is observational data from a meta-analysis, so it shows associations, not proven causes. The results compare other stems only to anatomic ones as a reference, and absolute rates for non-anatomic stems weren't given except for the revision rate of anatomic stems. This means we can't say for sure if one stem is 'best'—it depends on balancing lower revision risks against a possible higher infection chance.