Kurt S. Schulz

Proposed Definitions and Criteria for Reporting Time Frame, Outcome, and Complications For Clinical Orthopedic Studies in Veterinary Medicine

Outcome, and Complications For Clinical Orthopedic Studies in Veterinary Medicine James L. Cook, DVM, PhD, Diplomate ACVS, Richard Evans, PhD, Michael G. Conzemius, DVM, PhD, Diplomate ACVS, B. Duncan X. Lascelles, BVSc, PhD, Diplomate ECVS, Diplomate ACVS, C. Wayne McIlwraith, BVSc, PhD, Diplomate ACVS, Antonio Pozzi, DMV, MS, Diplomate ACVS, Peter Clegg, MA, VetMB, PhD, Diplomate ECVS, MRCVS, John Innes, BVSc, PhD, DSAS (Orth), MRCVS, Kurt Schulz, DVM, Diplomate ACVS, John Houlton, MA, VetMB, DVR, DSAO, MRCVS, Diplomate ECVS, Lisa Fortier, DVM, PhD, Diplomate ACVS, Alan R. Cross, DVM, Diplomate ACVS, Kei Hayashi, DVM, PhD, Diplomate ACVS, Amy Kapatkin, DVM, MS, Diplomate ACVS, Dorothy Cimino Brown, DVM, MSCE, Diplomate ACVS, and Allison Stewart, DVM, MS, Diplomate ACVS Comparative Orthopaedic Laboratory, University of Missouri, Columbia, MO, College of Veterinary Medicine, University of Illinois, Urbana, IL, College of Veterinary Medicine, University of Minnesota, St. Paul, MN, Comparative Pain Research Laboratory, North Carolina State University,

Techniques of Application and Initial Clinical Experience with Sliding Humeral Osteotomy for Treatment of Medial Compartment Disease of the Canine Elbow

OBJECTIVE To determine medium-term clinical efficacy of sliding humeral osteotomy (SHO) for treatment of lameness and elbow pain associated with clinically diagnosed elbow disease featuring cartilage eburnation of the medial elbow compartment (medial compartment disease--MCD). STUDY DESIGN Case series. ANIMALS Dogs (n=49) with severe or persistent lameness attributable to MCD. METHODS Signalment, lameness history, and preoperative imaging findings were recorded. A custom, locking, stepped SHO plate was applied to the medial aspect of the humerus, stabilizing a mid-diaphyseal transverse osteotomy, medially translating the distal segment relative to the proximal segment. Three variants of technique of application were used and outcomes compared between respective patient groups. Outcome measures included lameness scoring, anatomic measures, VAS scoring of elbow pain, and owner assessment of function. Measures recorded preoperatively, 12, and 26 weeks postoperatively were compared. RESULTS Of 59 limbs that had SHO, 39 had preoperative focal treatment of the diseased medial aspect of the coronoid process. Mean +/- SD dog age was 45.5 +/- 37.48 months and body weight ranged from 13.6 to 46.7 kg. Mean preoperative duration of lameness was 14.7 +/- 18.50 months. Lameness improved for all limbs by 26 weeks, and resolved in 21/32 limbs. Significant improvements in postoperative elbow pain scores and most owner assessments of function were observed. Incidence of major complications requiring surgical intervention was 17.2%, 22.2%, and 4.8% for each of the 3 technique variants described. Histologic examination of 2 elbows at >12 months revealed fibrocartilage cover of medial aspect of humeral condyle. CONCLUSIONS Canine SHO with or without focal treatment of the diseased medial aspect of the coronoid process ameliorates lameness and pain associated with MCD at medium-term follow-up. Application technique is critical to minimizing morbidity. CLINICAL RELEVANCE SHO is appropriate for clinical management of pain and lameness in select cases of canine MCD.

Mechanical Comparison of 3.5 mm Broad Dynamic Compression Plate, Broad Limited-Contact Dynamic Compression Plate, and Narrow Locking Compression Plate Systems Using Interfragmentary Gap Models

OBJECTIVES To compare (1) pullout properties between 3.5 mm cortical and locking screws, and (2) mechanical properties and gap displacements between the 3.5 mm broad limited-contact dynamic compression plate (LC-DCP), broad dynamic compression plate (DCP), and narrow locking compression plate (LCP), during axial loading of plate-stabilized diaphyseal fragments with an interfragmentary gap. STUDY DESIGN In vitro mechanical testing of implanted polyurethane foam (PUF) hollow cylinders that simulated compact or osteopenic diaphyseal bone. SAMPLE POPULATION (1) Five cortical and locking screws and (2) 4 PUF-plate constructs for each plate type; using high- and low-density (0.8 and 0.32 g/cm(3)) cylinders. METHODS (1) Screws were completely extracted at 5 mm/min. (2) Plated constructs were axially compressed at 300 N/s for 10 cycles from 5 to 355 N to determine gap displacement during physiologic loading, followed by single cycle increasing load to failure. RESULTS Pullout properties were not different between screw types. All plate constructs had yield loads over 3 times trotting loads. Gap closure occurred with LC-DCP and DCP constructs, but not LCP constructs. LCP construct properties were most similar to LC-DCP and DCP construct properties in the low-density model. CONCLUSION All plate systems sustained physiologic limb loads. Only LCP constructs maintained some gap integrity, although LC-DCP and DCP screws were placed in neutral position. CLINICAL RELEVANCE The LCP system is more likely than LC-DCP and DCP systems, with neutrally positioned screws, to maintain a planned interfragmentary gap, although gap strains range from 0% to 15% across the 2 mm gap during a trot load.

Measurement of humeroradial and humeroulnar transarticular joint forces in the canine elbow joint after humeral wedge and humeral slide osteotomies.

OBJECTIVE To determine the effect of humeral wedge and humeral slide osteotomies on force distribution between the articular surfaces of the humerus and the radius and ulna in normal canine thoracic limbs. STUDY DESIGN In vitro mechanical testing. SAMPLE POPULATION Cadaveric canine right thoracic limbs (n=12). METHODS Transarticular elbow force maps were measured using a tactile array pressure sensor in elbow joints of axially aligned limbs under 200 N axial load before and after humeral wedge and humeral slide osteotomies. RESULTS Loading induced 2 distinct areas of high forces that corresponded with the proximal articular surfaces of the radius and ulna. Mean force on the proximal articular surface of the ulna was reduced by 25% and 28% after 4 and 8 mm sliding osteotomies, respectively. Statistically significant differences were not observed for the wedge osteotomies. CONCLUSION Humeral slide osteotomy significantly decreases force on the proximal articular surface of the ulna. CLINICAL RELEVANCE The proximal articular surface of the ulna contributes significantly to load transfer through the canine elbow joint. Abnormalities that significantly increase this force might contribute to canine elbow dysplasia, specifically fragmentation of the medial coronoid process and osteochondritis dissecans of the medial aspect of the humeral condyle. Under the conditions studied, the overall reduction in mean joint surface force across the proximal articular surface of the ulna after humeral slide osteotomy indicates that this technique merits further investigation for potential use in medial compartmental osteoarthritis of the canine elbow joint.

Inadvertent prostatectomy as a complication of cryptorchidectomy in four dogs

Inadvertent prostatectomy was identified as a complication of cryptorchidectomy in four dogs. Surgical correction of the resulting urethral trauma was attempted in each case. One case was euthanized due to a poor prognosis for recovery. Three cases survived without clinical evidence of urinary incontinence. Inadvertent prostatectomy during cryptorchidectomy may be avoided by adequate surgical exposure and proper identification of the abdominally retained testicle.

Hip toggle stabilization using the TightRope® system in 17 dogs: technique and long-term outcome.

OBJECTIVE To describe the technique for, and long-term clinical outcome of, a modified hip toggle stabilization using the TightRope® system for coxofemoral luxation repair. STUDY DESIGN Retrospective case series. METHODS Medical records (July 2008-July 2010) including radiographs (17 limbs) of dogs that had coxofemoral luxation repaired with the TightRope system were reviewed. Follow-up (≥12 months) was obtained by telephone interview of owners. Six dogs were available for re-evaluation, radiographs, and objective gait analysis. RESULTS Follow-up (mean, 24 months; range, 12-43 months) by telephone interview was available for 17 dogs. Of these, 6 dogs were re-evaluated (mean, 7.5 months; median 12.5 months: range, 4-24 months) and had gait analysis. Mean duration of luxation before surgical intervention was 7.5 days (median, 7 days; range, 2-44 days). There was a single case of relaxation 27 months postoperatively. One dog died from non-surgical related circumstances. Objective gait analysis showed equal pelvic limb use in all 6 dogs available for re-evaluation. All owners of living dogs reported limb function as being good to excellent, and perceived that their dogs were pain free. Radiographs (mean, 7.5 months; median, 12.5 months; range, 4-24 months post surgery) of 6 dogs showed no progression of osteoarthritis in comparison to immediate postoperative radiographs. CONCLUSIONS Hip toggle with the TightRope system as a prosthetic ligament of the head of the femur produces a favorable clinical outcome with high owner acceptance.Objective To describe the technique for, and long-term clinical outcome of, a modified hip toggle stabilization using the TightRope® system for coxofemoral luxation repair. Study Design Retrospective case series. Methods Medical records (July 2008–July 2010) including radiographs (17 limbs) of dogs that had coxofemoral luxation repaired with the TightRope system were reviewed. Follow-up (≥12 months) was obtained by telephone interview of owners. Six dogs were available for re-evaluation, radiographs, and objective gait analysis. Results Follow-up (mean, 24 months; range, 12–43 months) by telephone interview was available for 17 dogs. Of these, 6 dogs were re-evaluated (mean, 7.5 months; median 12.5 months: range, 4–24 months) and had gait analysis. Mean duration of luxation before surgical intervention was 7.5 days (median, 7 days; range, 2–44 days). There was a single case of relaxation 27 months postoperatively. One dog died from non-surgical related circumstances. Objective gait analysis showed equal pelvic limb use in all 6 dogs available for re-evaluation. All owners of living dogs reported limb function as being good to excellent, and perceived that their dogs were pain free. Radiographs (mean, 7.5 months; median, 12.5 months; range, 4–24 months post surgery) of 6 dogs showed no progression of osteoarthritis in comparison to immediate postoperative radiographs. Conclusions Hip toggle with the TightRope system as a prosthetic ligament of the head of the femur produces a favorable clinical outcome with high owner acceptance.

Calcinosis circumscripta of the thoracic wall in a German shepherd dog.

Calcinosis circumscripta of the left thoracic wall was diagnosed in a six-month-old, female German shepherd dog by thoracic radiography and ultrasonographic-guided biopsy. The puppy developed the lesion following a left thoracotomy to repair a patent ductus arteriosus. Complete resolution occurred following surgical excision of the lesion. Calcinosis circumscripta associated with routine surgical manipulation and postoperative inflammation has been reported rarely but should be suspected when a focal, mineralized lesion occurs at a previous surgical site, especially in German shepherd dogs.

Forelimb lameness in the adult patient.

Lameness of the forelimb may be one of the more frustrating problems in small animal orthopedics. It is likely that numerous causes of forelimb lameness are not yet defined or well understood. The common and some less common causes of forelimb lameness are discussed as well as their means of diagnosis. The application of new diagnostic tools including arthroscopy and ultrasound are also discussed.

Repair of Monteggia fractures using an Arthrex Tightrope system and ulnar plating.

Objective: To report the outcome after treatment of Monteggia fractures (MF) using a novel surgical technique. Study design: Clinical reports. Methods: One dog and 1 cat were treated for MF by use of a Tightrope suture, toggle, and button implant. In both patients the fracture/luxations were reduced using an open technique and the tightrope was placed using a cannulated drill system and guide wire from cranial to caudal. Cases were retrospectively reviewed at 1, 5, and 8 weeks (cat) and at 4 weeks and 4 months (dog) for complications and outcome. Outcomes were measured by subjective assessment of range of motion comparing affected to unaffected limbs, and lameness scoring and by client description of function. Results: Both animals returned to normal function with range of motion close to that of the unaffected limb. No complications were recognized. Conclusions: Tightrope repair of MF resulted in excellent clinical results with no complications.OBJECTIVE To report the outcome after treatment of Monteggia fractures (MF) using a novel surgical technique. STUDY DESIGN Clinical reports. METHODS One dog and 1 cat were treated for MF by use of a Tightrope suture, toggle, and button implant. In both patients the fracture/luxations were reduced using an open technique and the tightrope was placed using a cannulated drill system and guide wire from cranial to caudal. Cases were retrospectively reviewed at 1, 5, and 8 weeks (cat) and at 4 weeks and 4 months (dog) for complications and outcome. Outcomes were measured by subjective assessment of range of motion comparing affected to unaffected limbs, and lameness scoring and by client description of function. RESULTS Both animals returned to normal function with range of motion close to that of the unaffected limb. No complications were recognized. CONCLUSIONS Tightrope repair of MF resulted in excellent clinical results with no complications.

Unusual urethral calculi in two male dogs.

The clinical presentation and advanced size of the two calculi described in this report are both atypical and noteworthy. Both dogs were presented initially with signs of hematuria, stranguria, and perineal discomfort. Each calculus was visible on survey abdominal radiographs and was present in the region of the ischial arch. Both dogs underwent a perineal urethrotomy to retrieve the calculus. Resolution of clinical signs was obtained in one case, which was referred within 2 months of the onset of clinical signs. The second dog was medically managed for approximately 2.5 years before referral. Surgical intervention failed to restore urinary continence in this second dog. Early detection of similar cases may be important in optimizing clinical outcome following appropriate treatment.