The influence of age at total hip replacement on perioperative complications associated with a press-fit cementless stem with lateral bolt in dogs.

Objective: To assess the influence of age on perioperative stem-associated complications when total hip replacement (THR) was performed with a BFX lateral bolt stem.

Study design: Retrospective (2017-2022).

Sample population: A total of 197 client-owned dogs.

Methods: Medical records of dogs that underwent THR with a lateral bolt stem were reviewed. Perioperative complications were recorded. Stem and femoral features were measured on postoperative and follow-up radiographs. The population was divided into juveniles (6-10 months), adults (>10 months to <7 years), and older dogs (≥7 years old). Association between groups and perioperative complications was assessed.

Results: Two-hundred and fifty five THRs were recorded: 139 unilateral and 58 bilateral. Intraoperative and early postoperative stem complication rates were 8.6% and 2%, respectively. Juveniles were at increased risk of developing intraoperative fissures. Age was not associated with early postoperative stem complications. German shepherd dogs were associated with postoperative fractures. Subsidence was weakly, but positively, associated with weight and canal flare index.

Conclusion: Juveniles were at increased risk of developing fissures. There was no difference in postoperative stem complications among age groups. German shepherds were at increased risk of postoperative fracture despite the use of a lateral bolt stem. More studies are required to assess the effect of giant breeds on the risk of subsidence, as well as the effect of young age on fissure development.

Clinical significance: Age influenced the development of intraoperative, but not postoperative, stem complications with a lateral bolt stem. Prophylactic cerclage application could be considered in juvenile and German shepherd dogs.