Histologic changes in the dog acetabulum following total hip replacement with current cementing techniques

Area of Science:

• Veterinary Orthopedics
• Biomaterials Science
• Surgical Techniques

Background:

• Total hip replacement (THR) is a common orthopedic procedure in veterinary medicine.
• Current cementing techniques aim for stable fixation of prosthetic components.
• Understanding the bone-implant interface is crucial for long-term implant success.

Purpose of the Study:

• To investigate the histologic changes in canine acetabuli following total hip replacement using current cementing techniques.
• To evaluate the bone-cement interface and bone remodeling response over a 6-month period.

Main Methods:

• Histologic examination of acetabular tissues from adult dogs after total hip replacement.
• Assessment of bone remodeling, bone-cement interface, and fibrous membrane formation.
• Quantitative analysis of membrane thickness and bone apposition.

Main Results:

• Active bone remodeling and significant hypertrophy of trabecular bone were observed within 2 weeks and persisted for 6 months.
• A thick fibrous membrane (average 0.4 mm) formed at the bone-cement interface in 83 of 84 specimens.
• Direct bone-to-cement apposition was limited to small fixation holes.

Conclusions:

• The formation of a fibrous membrane at the bone-cement interface is a consistent finding with current acetabular cementing techniques in dogs.
• Acetabular geometry may hinder effective cement pressurization, contributing to membrane formation.
• Further research into optimizing cementing strategies is warranted to improve bone integration and long-term outcomes in canine THR.