Carvajal et al: Breakage of cementless press‐fit femoral stems following total hip arthroplasty in dogs: 14 cases (2013–2023)
Veterinary Surgery 3, 2025

🔍 Key Findings

Incidence of BFX lateral bolt stem breakage: 2.95% (13 dogs, 14 stems)

Implant factors:

• 13/14 were BFX lateral bolt stems (sizes #5–7)
• +9 necks used in 5/11 of 17 mm heads
• 10/14 stems undersized based on radiographs
• 10/13 dogs exceeded weight limits for implanted stem size

Malalignment:

• 10/14 had varus alignment (median 3.9°)
• 8/14 had insufficient proximodistal seating

Breakage site: Proximolateral shoulder in all cases

Revision outcomes:

• 11 revised (7 CFX, 3 larger BFX, 1 collared)
• 9/10 revised dogs regained full function
• Complications: 1 rebreakage, 1 periprosthetic fracture, 1 fixation failure

Histopathology:

• Electron microscopy showed fatigue striations and incomplete bead fusion

Conclusion: Avoid small BFX lateral bolt stems if undersized or if long necks required; use weight guidelines to prevent fatigue failure.