Laurie's Blogs.

Muroi N, Kanno N, Harada Y, Hara Y. A Retrospective Study of Risk Factors Associated with Refracture after Repair of Radial-Ulnar Fractures in Small-Breed Dogs. Vet Comp Orthop Traumatol. 2025 Mar;38(2):77-86. 

Introduction

The paper investigates radial-ulnar fractures in small-breed dogs (≤5 kg), focusing on refracture risks after bone union, with or without plate removal. These fractures commonly occur in the distal third of the radius, with higher complication rates in small breeds compared to larger ones. While internal fixation with plates and screws is effective (100% union rate), refracture after union is a notable but understudied complication in veterinary orthopedics.

Methods

The study analyzed 181 limbs from small-breed dogs treated with plates and screws across 10 hospitals (2010–2016). Inclusion required first-time radial fractures, no infections, successful union, and no other health issues. Dogs were divided into two groups: non-plate removal (P group, 141 limbs) and plate removal (R group, 40 limbs).

Results

Refracture occurred in 10 of 181 limbs (5.5%): 5 in the P group (3.5%) at the distal screw hole and 5 in the R group (12.5%) at the initial fracture site. Plate removal was significantly associated with refracture (p=0.04), though the association was weak.

• In the P group, younger age, faster healing, greater distal screw position change, and higher screw-to-bone diameter ratio (SBDR) were linked to refracture; multivariate analysis confirmed distal screw position change as a key risk factor. 
• In the R group, lower bone density and radial thickness at final follow-up were significant risk factors suggesting the role of implant induced osteoporosis post-plate removal.

Discussion

The study suggests retaining plates in high-risk cases (e.g., young dogs or those with implant-induced osteoporosis signs) and using smaller SBDR or external support to mitigate risks role post-removal.

LEH Thoughts:

From a rehab perspective, I like to know the complications of various veterinary surgical procedures.  Should a dog with a repaired radial-ulnar fractures show up in my clinic appearing to favouring its surgical leg, I would want to palpate the distal screw.  I would educate owners (especially of young dogs) that they need to be vigilant about not letting their dog jump down from a height, perhaps into perpetuity.  If a dog has had a plate removal, I would take extra caution to ensure that my rehab included techniques to stimulate bone healing / regrowth, and again educate the owners about the potential to refracture at the site. All in all, I think this is simply good information to know!

Cheers,

Laurie