Kate Whybrow¹, Alexandros Bourbos¹, Kevin Parsons¹, Alex Chan², Nicolas Barthelemy¹, Benito de la Puerta³, Elvin Kulendra³, Carlos Sanchez⁴, Mariette Pilot¹

¹Langford Vets, Bristol, United Kingdom. ²Bristol Vet Specialists, Bristol, United Kingdom. ³North Downs Specialist Referrals, Surrey, United Kingdom. ⁴Royal Veterinary College, London, United Kingdom

Objectives

To compare short-term postoperative complications and outcomes in giant-breed dogs (>50 kg) undergoing tibial plateau levelling osteotomy (TPLO) stabilised with 3.5mm Broad versus 4.5mm TPLO plates.

Methods

Multi-centre, retrospective study. Medical records from four referral hospitals (2013–2025) were reviewed. Inclusion criteria were giant-breed dogs ≥50 kg undergoing TPLO stabilised with either plate and minimum six-week follow-up. Descriptive statistics and regression analyses were performed. Short-term functional outcome and radiographic healing (mRUST) were evaluated. Fifty-eight dogs (67 stifles) were included. Forty-three (49 stifles) in 3.5mm Broad and 15 dogs (18 stifles) 4.5mm. 

Results

Major complications were more common in the 3.5mm Broad group (77% vs 17%; p = 0.04). In the 3.5mm Broad group (complication rate was 26.5%) 76.9% (10/13) major and 23.1% (3/13) minor complications occurred. Major complications comprised surgically managed pes avulsion, instability, surgical site infection (SSI) (n=1) and late meniscal tear (n=1), and medically managed SSI (n=7) and fibula fracture (n=1). In the 4.5mm group (33.3% complication rate),17% (1/6) major, medically managed SSI, and 83% (5/6) minor occurred.

No difference in six-week functional outcome was observed. Median mRUST scores suggested more advanced early healing in the 3.5mm Broad group (p = 0.016).

Statement: Impact/ Clinical Significance

Major complications were less frequent in the 4.5mm group, and none required revision surgery. In contrast, the 3.5mm Broad plate group demonstrated a significantly higher likelihood of major complications, particularly surgical site infection. These findings suggest that the 4.5mm TPLO plate may offer protection against major postoperative complications in giant breed dogs.