Early Performance of a Collared, Triple-Tapered Cementless Femoral Stem in Primary Total Hip Arthroplasty.

Background/Objectives: Collared triple-tapered cementless femoral stems are designed to optimize metaphyseal fit, stability, and osseointegration following total hip arthroplasty (THA). This study evaluated 90-day revision and complication rates, short-term functional recovery, and operative characteristics of a modern collared triple-tapered stem in a same-day discharge ambulatory surgery center cohort. Methods: This retrospective cohort study reviewed 525 consecutive primary direct anterior THAs performed by 15 fellowship-trained arthroplasty surgeons at one group operating across several ASCs between September 2024 and August 2025. Ninety-day all-cause revision, stem-specific revision, periprosthetic fracture, and other early postoperative complications were evaluated. Kaplan-Meier estimates were used to account for variable follow-up within the 90 days. PROMs (HOOS-JR, FJS, VR-12) were collected preoperatively and at 12 weeks. Operative time was evaluated using within-surgeon analyses restricted to surgeons who used both an automated impaction device (AID) and manual impaction. Results: At a mean effective follow-up of 110 ± 39 days, the 90-day Kaplan-Meier revision-free estimate was 99.62% for all-cause revision and 99.81% for stem revision. Two patients (0.4%) underwent revision (one Vancouver B2 fracture; one infection treated with DAIR with stem retention). The early periprosthetic fracture rate was 0.2%. Five patients (1.0%) experienced dislocation, all of whom were managed with closed reduction. HOOS-JR improved by 28.7 points and FJS by 41.9 points at 12 weeks (both p < 0.0001), with 84.2% and 85.8% MCID achievement, respectively. Seven surgeons used both techniques, contributing 384 AID and 58 manual cases to the within-surgeon analysis. AID use was not associated with operative time after accounting for surgeon (adjusted difference, 0.18 min; 95% CI, -2.04 to 2.39; p = 0.8764). Conclusions: This collared, triple-tapered cementless stem was associated with low 90-day revision and complication rates and clinically meaningful short-term functional improvement in a same-day discharge ambulatory population. AID use was not associated with operative time after accounting for surgeon, although the study was not powered to compare uncommon complications between impaction methods.