Revision rates of porous-coated versus grit-blasted femoral stems in cementless total hip arthroplasty: A systematic review.

BACKGROUND

Femoral stem surface design may influence outcomes in cementless primary total hip arthroplasty (THA). This review compares porous-coated versus grit-blasted stems for revision, complications, and reasons for failure.

METHODS

Following PRISMA, PubMed, Embase, and Cochrane were searched through October 17, 2024, using keywords and controlled vocabulary for porous-coated stems, grit-blasted stems, and primary cementless THA. Outcomes included revision rate, indications, implant characteristics, reasons for revision (periprosthetic fracture, loosening, dislocation, infection), and functional results (Harris Hip Score, HHS) when available.

RESULTS

Twelve studies (1987 hips) met inclusion. Aggregated revision rates were 1.5 % for porous-coated stems (10/650 hips) versus 9.2 % for grit-blasted stems (123/1337 hips). Studies of porous-coated implants reported HHS improvements of 16-47.6 points, with postoperative scores up to 96.1. Reported failure modes included loosening, periprosthetic fracture, dislocation, and infection; across included reports, porous-coated stems had lower overall revision rates and fewer early mechanical complications.

CONCLUSION

In primary cementless THA, porous-coated femoral stems are associated with lower revision rates and improved function compared with grit-blasted stems. These differences may relate to more physiologic proximal load transfer, reduced stress shielding, and enhanced osseointegration linked to anatomic design features (e.g., medial cutouts, variable proximal geometry). Given heterogeneity in study designs, implant eras, surgical techniques, and patient selection, well-controlled, long-term comparative studies with standardized endpoints are needed to isolate the independent effect of surface design on failure mechanisms.

PROSPERO REGISTRATION ID: CRD42024598087.