Titles and Education

1. Melita Grunow Family Professor of Companion Animal Health
2. BVSc University of Bristol 1985
3. MVetClinStud, The University of Sydney 1992
4. PhD, University of Bristol 1990
5. Membership of the Australian College of Veterinary Scientists in Small Animal Surgery 1992
6. Membership of the American College of Veterinary Surgeons (Small Animal Surgery) 1995
7. Membership of the European College of Veterinary Surgeons 1996
8. Fellow of the Royal College of Veterinary Surgeons 2018

Research

The Comparative Orthopaedic & Genetics Research Laboratory has several current research areas of interest. Research interests include pathogenesis of stress (fatigue) fractures, functional adaptation of bone, genomic dissection of orthopaedic traits, cruciate rupture in dogs, long bone fracture repair, and clinical trials studying treatment of canine osteoarthritis using of regenerative medicine therapies such as stem cells and platelet-rich plasma.

Pathogenesis of spontaneously occurring stress fractures, particularly condylar fracture in racing Thoroughbreds is a focus. We are particularly interested in the remodeling response in the subchondral plate that appears to promote condylar fracture propagation. We are now using vertical and horizontal CT scanning in the standing horse with the Asto CT LLC Equina system that was developed at UW Madison. This imaging system can readily acquire CT images of the limbs of racehorses to screen for incipient stress fracture and is well suited to routine screening of athletic horses for bone injury.

A major focus for the laboratory is genomic dissection of canine and equine disease. Current projects include genome-wide association studies of cruciate ligament rupture and acquired laryngeal paralysis in the Labrador Retriever. In addition we are studying the genetic contribution to degenerative suspensory ligament desmitis in the Peruvian Horse and fibrotic myopathy in the German Shepherd Dog. A combination of SNP genotyping, RNA-Seq and whole genome sequencing is being used for this work. Breed-related genomic structural variation in the dog is also a focus, as the current reference assembly is derived from a single Boxer dog.

Current areas of cruciate rupture research include the immune response within the stifle synovium that is an early pathologic feature of the condition that precedes ligament rupture. We are working on identification of a therapeutic target for disease-modifying treatment for the stable stifle in affected dogs.

As part of our clinical trial work in client-owned dogs, we are also working on development of improved methods for analysis of force-platform gait data.

Please visit the Comparative Orthopaedic Research Laboratory http://www.vetmed.wisc.edu/lab/corl

Responsibilities

Teaching of small animal orthopaedic surgery and comparative orthopaedic science to veterinary students, veterinary surgery residents, graduate students and postdoc trainees.

Co-Director of the Comparative Orthopaedic and Genetics Research Laboratory

Clinical Interests

Small animal orthopaedic surgery, particularly fracture repair, treatment of dogs with cruciate rupture, and canine arthritis clinical trials.

Founder and director of Asto CT LLC, which is continuing to develop the Equina system for CT imaging of the head and neck in the standing horse. I am particularly interested in implementation of this system for routine screening of racehorses for bone injury, particularly racing Thoroughbreds.

Graduate Training

Comparative Biomedical Sciences Graduate Program trainer. Students who recently completed graduate degrees include Sabrina Brounts (PhD – 2018), ‘Evaluation of acoustoelastography in equine tendon and ligament healing,’ Susannah J. Sample (PhD – 2011), ‘Functional adaptation of the skeleton and the nervous system’, Lauren Baker (MS – 2014), ‘Genome-wide association study of cruciate rupture in the dog’, Molly Racette (MS – 2014) ‘MRI prediction of cruciate ligament structural properties’, and Adam Biedrzycki (PhD – 2015) ‘Bioengineering of tendons using controlled spatiotemporal release of multiple growth factors and concurrent monitoring of healing via elasticity mapping ultrasonography’, Jason Bleedorn (MS – 2015) ‘Mechanically-induced signaling events during bone loading’.

Recent Publications

1. Yarnall BW, Chamberlain CS, Hao Z, Muir P. Pro-inflammatory polarization of stifle synovial macrophages in dogs with cruciate ligament rupture. Veterinary Surgery. 2019, in press.
2. Baker LA, Rosa GJM, Hao Z, Piazza A, Hoffman C, Binversie EE, Sample SJ, Muir P. Multivariate genome-wide association analysis identifies novel and relevant variants associated with anterior cruciate ligament rupture risk in the dog model. BMC Genetics. 2018;19:39.
3. Sample SJ, Racette MA, Hans EC, Volstad NJ, Holzman G, Bleedorn JA, Schaefer SL, Waller KR 3rd, Little JP, Hao Z, Block WF, Vavken P, Murray MM, Muir P. Use of a platelet-rich plasma-collagen scaffold as a bioenchanced repair treatment for management of partial cruciate ligament rupture in dogs. PLoS One. 2018;13:e0197204.
4. Hoffman CL, Volstad N, Hans EC, Nemke B, Muir P. Effect of contact time on ground reaction force variance in force platform gait analysis of a heterogenous sample of clinically normal dogs. Am J Vet Res. 2018;79:546-554.