Assess union rate, complications, and outcomes of large series of contemporary extended trochanteric osteotomies (ETOs) performed during revision THAs.

From 2003 to 2013, 612 ETOs were performed during revision THAs using 2 techniques. 367 were Paprosky type and 245 were Wagner type. Indications were aseptic loosening (65%), periprosthetic joint infection (18%), periprosthetic fracture (6%), femoral implant fracture (5%), and other (6%). Mean age 69 years, 58% male. Median follow-up 5 years (range, 2.1 to 13 years).

Mean Harris Hip Scores increased from 57 preoperatively to 77 at latest follow-up (p=0.0001). Radiographic union of the extended osteotomy occurred in 98%. There were 9 ETO nonunions. Mean time to union of the distal transverse osteotomy was 5.9 months (range, 1 month − 2 years). Mean trochanteric osteotomy fragment migration prior to union was 3 mm (range, 0–29 mm). Over 1 cm of migration occurred in 7.4%. Intraoperative fracture of the ETO diaphyseal fragment occurred in 4%, and postoperative greater trochanter fractures in 8.8%. Other complications: dislocation in 5.7% and infection in 3.4%. Dislocation occurred in 19 of 462 with ETO migration < 1 cm and 4 of 39 with ETO migration ≥1 cm (p=0.08). Ten year survivorship free of revision for aseptic femoral loosening, free of any component removal or revision, and free of reoperation were 97%, 91%, and 82%, respectively.

The union rate after ETO was high and notable trochanteric migration was infrequent. The most common complication was fracture intraoperatively or postoperatively of the osteotomy fragment.