Arthur George, 6 Yr old MN Bassett hound

Clinical

• Typical chondrodystrophic bi-apical antebrachial deformity, with marked associated external rotation of paw, worse on the left side
• Progressive ‘collapse’ (inability to maintain sufficient extension of carpus for weight-bearing) in recent months

Investigation

• CT confirms antebrachial deformity typical of breed type
• Lateral subluxation of radial head creates functional varus at the elbow

Correction

• 3D models created through Ivalalearn.com
• Osteotomies planned and executed on model
• Paired 2.7mm N2 Evolox custom plates contoured to corrected model
• Surgical plan followed and pre contoured plates applied to patient
• Osteotomies temporarily stabilised using arthrodesis wires during plating

Tricky part

• Derotation is impeded by tension in extensors, since their distance of travel is increased through correction of distal valgus and by corrective internal rotation distally
• Elective shortening of radius (and, of necessity of ulna), of approximately 2mm enabled rotation. Happily the precontoured plates still fitted!

Of course, it is easy to derotate the plastic model without the surrounding inelastic soft tissues, but it is prudent to remove a generous sliver of length from distal radius (and as much ulna as necessary) on the model before contouring the implant/s to allow derotation in the clinical case.