Erick L. Egger

Comparison of Surgical Treatment Options for Cranial Cruciate Ligament Disease in Large‐Breed Dogs with Excessive Tibial Plateau Angle

OBJECTIVE To identify surgical techniques performed by veterinary surgeons for the treatment of cranial cruciate ligament disease in large-breed dogs with excessive tibial plateau angle (eTPA), compare their outcomes, identify risk factors for postoperative complications, and compare outcome and complication rate with tibial plateau leveling osteotomy (TPLO) in dogs without eTPA. STUDY DESIGN Multicenter, case-control study. ANIMALS eTPA group (TPA>or=35 degrees)=58 dogs (78 stifles); control group (TPA<or=30 degrees)=58 dogs (72 stifles). METHODS Control and eTPA group dogs were identified. Medical records, radiographic reviews, and pet-owner interviews were used to identify surgical treatments performed, their complications, and outcome. Odds ratios with 95% confidence intervals, chi(2) tests, and t-tests were calculated to discern differences between eTPA and control-group dogs. RESULTS TPLO was the most common treatment for eTPA. Owner-perceived outcome was superior for eTPA group dogs when TPLO resulted in TPA<or=14 degrees compared with those with postoperative TPA>14 degrees. Loss of tibial plateau leveling during convalescence was the most commonly observed major complication; addition of ancillary implants to TPLO significantly reduced its incidence. Postoperative complications were more common in dogs with eTPA than in dogs without eTPA; however, no difference in owner-perceived outcome was identified. CONCLUSIONS Surgical treatment of dogs with eTPA has a higher complication rate, but comparable outcome to that of dogs without eTPA. CLINICAL RELEVANCE Postoperative TPA<or=14 degrees and addition of ancillary implants are recommended when using TPLO to treat dogs with eTPA.Objective— To identify surgical techniques performed by veterinary surgeons for the treatment of cranial cruciate ligament disease in large-breed dogs with excessive tibial plateau angle (eTPA), compare their outcomes, identify risk factors for postoperative complications, and compare outcome and complication rate with tibial plateau leveling osteotomy (TPLO) in dogs without eTPA. Study Design— Multicenter, case–control study. Animals— eTPA group (TPA≥35°)=58 dogs (78 stifles); control group (TPA≤30°)=58 dogs (72 stifles). Methods— Control and eTPA group dogs were identified. Medical records, radiographic reviews, and pet-owner interviews were used to identify surgical treatments performed, their complications, and outcome. Odds ratios with 95% confidence intervals, χ2 tests, and t-tests were calculated to discern differences between eTPA and control-group dogs. Results— TPLO was the most common treatment for eTPA. Owner-perceived outcome was superior for eTPA group dogs when TPLO resulted in TPA≤14° compared with those with postoperative TPA>14°. Loss of tibial plateau leveling during convalescence was the most commonly observed major complication; addition of ancillary implants to TPLO significantly reduced its incidence. Postoperative complications were more common in dogs with eTPA than in dogs without eTPA; however, no difference in owner-perceived outcome was identified. Conclusions— Surgical treatment of dogs with eTPA has a higher complication rate, but comparable outcome to that of dogs without eTPA. Clinical Relevance— Postoperative TPA≤14° and addition of ancillary implants are recommended when using TPLO to treat dogs with eTPA.

Gastrocnemius tendon strain in a dog treated with autologous mesenchymal stem cells and a custom orthosis.

OBJECTIVE To report clinical findings and outcome in a dog with gastrocnemius tendon strain treated with autologous mesenchymal stem cells and a custom orthosis. STUDY DESIGN Clinical report. ANIMAL A 4-year-old spayed female Border Collie. METHODS Bone-marrow derived, autologous mesenchymal stem cells were transplanted into the tendon core lesion. A custom, progressive, dynamic orthosis was fit to the tarsus. Serial orthopedic examinations and ultrasonography as well as long-term force-plate gait analysis were utilized for follow up. RESULTS Lameness subjectively resolved and peak vertical force increased from 43% to 92% of the contralateral pelvic limb. Serial ultrasonographic examinations revealed improved but incomplete restoration of normal linear fiber pattern of the gastrocnemius tendon. CONCLUSIONS Findings suggest that autologous mesenchymal stem cell transplantation with custom, progressive, dynamic orthosis may be a viable, minimally invasive technique for treatment of calcaneal tendon injuries in dogs.Objective To report clinical findings and outcome in a dog with gastrocnemius tendon strain treated with autologous mesenchymal stem cells and a custom orthosis. Study Design Clinical report. Animal A 4-year-old spayed female Border Collie. Methods Bone-marrow derived, autologous mesenchymal stem cells were transplanted into the tendon core lesion. A custom, progressive, dynamic orthosis was fit to the tarsus. Serial orthopedic examinations and ultrasonography as well as long-term force-plate gait analysis were utilized for follow up. Results Lameness subjectively resolved and peak vertical force increased from 43% to 92% of the contralateral pelvic limb. Serial ultrasonographic examinations revealed improved but incomplete restoration of normal linear fiber pattern of the gastrocnemius tendon. Conclusions Findings suggest that autologous mesenchymal stem cell transplantation with custom, progressive, dynamic orthosis may be a viable, minimally invasive technique for treatment of calcaneal tendon injuries in dogs.

Prevalence of Dysphoria after Fentanyl in Dogs Undergoing Stifle Surgery

OBJECTIVE To describe the prevalence of dysphoria after intraoperative administration of fentanyl by infusion and identify other risk factors influencing this in dogs undergoing stifle surgery. STUDY DESIGN Prospective, randomized clinical study. ANIMALS Dogs (n = 92) that had tibial plateau leveling osteotomy (TPLO) or tibial tuberosity advancement (TTA). METHODS Dogs were anesthetized using a standardized anesthetic protocol, and randomly assigned to receive a loading dose followed by 1 of 3 infusions of fentanyl perioperatively: 2 μg/kg/h, 10 μg/kg/h, or 20 μg/kg/h. Dog characteristics and all additional medications were recorded and included as part of the statistical analysis. Dog behavior was scored before anesthesia and during recovery using a scale of 1-4 (Appendices A and B). If no improvement in behavior was seen in 3-5 minutes postextubation, dogs with a score of 3 or 4 during recovery were administered fentanyl (2 μg/kg intravenously [IV]) in the event that the behaviors associated with the higher scores were related to pain. If they did not respond favorably to the administration of additional fentanyl and wound palpation did not elicit a response, but the untoward behaviors continued, dogs were administered either a tranquilizer, sedative, or opioid antagonist, and were considered dysphoric. RESULTS Of 92 dogs, 22 (23.9%) were considered dysphoric using aforementioned criteria. CONCLUSIONS About one-fourth of dogs enrolled in this study were dysphoric based on study criteria.

In vitro comparison of proximal ulnar osteotomy and distal ulnar osteotomy with release of the interosseous ligament in a canine model.

OBJECTIVE To determine the effect of proximal ulnar osteotomy (PUO), distal ulnar osteotomy (DUO), and DUO with release of the interosseous ligament (DOLR) on displacement of the proximal ulna at the radioulnar joint. STUDY DESIGN Experimental mechanical study. SAMPLE POPULATION Cadaveric, skeletally mature canine thoracic limb pairs (n=11). METHODS Thoracic limbs disarticulated at the elbow were randomly assigned to 1 of 2 groups: (A) limbs were tested with no treatment (NOTX), then with PUO; (B) limbs were tested with DUO followed by DOLR. A distraction force was applied to the proximal ulna with the distal limb secured in a frame, and displacement of the proximal ulnar segment at the radioulnar joint was recorded. RESULTS Mean displacement was 0.36 mm (95% confidence interval [CI]: 0-1.12 mm) in the NOTX group, 4.68 mm (95% CI: 3.82-5.55 mm) for PUO limbs, 0.95 mm (95% CI: 0.52-1.39 mm) for the DUO group, and 4.36 mm (95% CI: 3.71-5.02 mm) for the DOLR group. Mean ulnar displacement of the DOLR group was significantly different compared with the DUO group, but there was no significant difference between the PUO and DOLR groups. CONCLUSIONS No significant difference was observed in displacement of the proximal ulnar segment after DOLR compared with PUO.

A Lifesaving Model: Teaching Advanced Procedures on Shelter Animals in a Tertiary Care Facility

It is estimated that there are over 5 million homeless animals in the United States. While the veterinary profession continues to evolve in advanced specialty disciplines, animal shelters in every community lack resources for basic care. Concurrently, veterinary students, interns, and residents have less opportunity for practical primary and secondary veterinary care experiences in tertiary-care institutions that focus on specialty training. The two main goals of this project were (1) to provide practical medical and animal-welfare experiences to veterinary students, interns, and residents, under faculty supervision, and (2) to care for animals with medical problems beyond a typical shelters technical capabilities and budget. Over a two-year period, 22 animals from one humane society were treated at Colorado State University Veterinary Medical Center. Initial funding for medical expenses was provided by PetSmart Charities. All 22 animals were successfully treated and subsequently adopted. The results suggest that collaboration between a tertiary-care facility and a humane shelter can be used successfully to teach advanced procedures and to save homeless animals. The project demonstrated that linking a veterinary teaching hospitals resources to a humane shelters needs did not financially affect either institution. It is hoped that such a program might be used as a model and be perpetuated in other communities.

Evaluation of strength at the acrylic-pin interface for variably treated external skeletal fixator pins.

OBJECTIVE To report pullout force to failure at the acrylic-pin interface for variably treated 3.2 mm external skeletal fixator pins. STUDY DESIGN In vitro biomechanical evaluation. SAMPLE POPULATION 3.2 mm external skeletal fixator pins in polymethylmethacrylate bars. METHODS 3.2 mm external skeletal fixator pins were used for each of 5 treatment groups: polished, unpolished, 3 notched, 5 notched, and machine knurled. Each pin was seated into a 2-cm-diameter acrylic connecting bar and tested in pullout force to failure. Each group consisted of 6 pins. The force required to remove the pins from the acrylic bar was measured and compared between groups. RESULTS Significant differences between treatment groups were determined (P<.05). Within a construct group failure mode was consistent. Fracture of the acrylic bar was only seen with knurled pin ends. CONCLUSIONS When using 2 cm acrylic bars in external skeletal fixation (ESF), a knurled pin shaft or a pin surface with 5 notches should be considered to improve the overall stability of the ESF construct.

Bending Characteristics of Polymethylmethacrylate Columns, Connecting Bars of Carbon Fiber, Titanium, and Stainless Steel Used in External Skeletal Fixation and an Acrylic Interface

OBJECTIVE To (1) mechanically evaluate polymethylmethacrylate (PMMA) columns of various sizes and compare them to connecting bar materials (carbon fiber composite, titanium, stainless steel) and (2) compare the properties of an intact PMMA column to those of an acrylic interface. STUDY DESIGN Experimental mechanical study. SAMPLE POPULATION Experiment 1: 6 groups of 6 specimens each; experiment 2: 2 groups of 12 specimens each. METHODS All specimens were tested in 3-point bending. Stiffness, yield strength, and ultimate strength values were calculated for each specimen. RESULTS PMMA 1 columns (23.25 mm) compared favorably to titanium or stainless-steel bars. PMMA 3 columns (30.15 mm) and carbon fiber bars had similar yield strength but PMMA 3 columns were less stiff than carbon fiber bars. PMMA 3 columns had lower bending modulus and a higher variability in their mechanical properties than PMMA 1 or PMMA 2 (25.64 mm) columns. Acrylic interface specimens were less strong but as stiff as intact specimens. CONCLUSION An acrylic interface was easily created and had acceptable biomechanical characteristics. CLINICAL RELEVANCE PMMA 2 and PMMA 3 columns are not recommended for clinical use at this time. Further tests are needed to analyze an acrylic patch in a more clinically relevant loading model.