Fundamental principles of rehabilitation and musculoskeletal tissue healing.

OBJECTIVE: To review fundamental principles of tissue healing and physical rehabilitation as they apply to dogs recovering from cranial cruciate ligament (CCL) surgery. STUDY DESIGN: Invited Review. SAMPLE POPULATION: None. METHODS: A multidisciplinary group of specialists in small animal surgery, rehabilitation/sports medicine, and human physical and occupational therapy reviewed the currently available evidence for rehabilitation post-CCL surgery. Because current evidence is limited, this group proposes guidelines for rehabilitation after CCL surgery based on the fundamental principles of tissue healing and physical therapy. RESULTS: This Review proposes four fundamental principles of small animal physical rehabilitation based on the foundations of tissue healing and patient-centric and goal-oriented therapy. Postoperative rehabilitation programs should be designed such that patient progress is based on individual assessment according to the degree of tissue healing, strength, and achievement of functional goals. Therapists must fully understand phases of tissue healing, reassess the patient frequently, and use clinical reasoning skills to progress treatment appropriately for the individual patient. CONCLUSION: Until more robust evidence is available to guide treatment protocols, fundamental principles of rehabilitation should ideally be adhered to when providing rehabilitation, including after CCL surgery. CLINICAL SIGNIFICANCE: While this Review specifically addresses post-CCL surgery rehabilitation, these fundamental principles should be applied broadly to animals enrolled in rehabilitation programs.

Use of acoustic myography to evaluate forelimb muscle function in retriever dogs carrying different mouth weights.

Objectives: To evaluate the effect of mouth weight on gait and relative function of forelimb muscles in retriever hunting dogs as a possible explanation for biceps tendinopathy. Methods: Ten sound retriever dogs underwent acoustic myography, measuring efficiency (E-score), spatial summation (S-score), and temporal summation (T-score) during walk and trot on a pressure-sensitive walkway while carrying a 0 lb (0 kg), 1 lb (0.45 kg), and 3.2 lb (1.45 kg) mouth weight. Gait data included total pressure index (TPI), step length, and stance time. Statistics included a mixed effects model significant at p < 0.05. Results: Forelimb TPI increased with increasing weight. There was no significant change in individual muscle parameters in response to weight. Significance was found in between-muscle comparisons. For walk, T-score was significantly lower in triceps vs. brachiocephalicus with 1 lb, not with 3.2 lb., S-score was significantly lower in the biceps at 0, 1 lb, and triceps at 0 lb. when compared to brachiocephalicus, E-score was significantly lower in deltoideus vs. brachiocephalicus at trot with l and 3.2 lb. There was an overall significant effect of muscle on T-score at trot, but no individual muscle comparison was significant. Conclusion: Forelimb load increases with mouth weight. Deltoideus had a longer contraction time in response to increasing weight at trot when compared to brachiocephalicus. The biceps muscle did not show increased work in response to increasing weight. Clinical relevance: The underlying etiology of biceps tendinopathies in retriever dogs remains uncertain but is not due to increasing weight.

Return to Sport after Injury: A Web-Based Survey of Owners and Handlers of Agility Dogs.

OBJECTIVE: Internet-based surveys of canine agility injury rates have been performed, but unlike with equine and human competition, there is a paucity of data on return to sport of agility dogs after orthopaedic injury. This study aimed to gather initial information on canine return to competition. METHODS: Data were collected using an internet-based 18-question survey of 427 dogs from around the world (92.4% North America). Relationships between categorical variables and return to sport were assessed with descriptive statistics, a chi-squared or Fischer's exact test. Categorical variables included breed, sex, age, surgery, stifle versus shoulder surgery, stifle versus all other types of surgery and drop in competition class. Significance was set at p≤ 0.05. RESULTS: Of 427 completed surveys, age, sex and breed were not significantly associated with return to competition. Overall, 67.4% of dogs returned to competition post-orthopaedic injury, but jump height was lowered in 47% of cases. Dogs were returned to competition post-stifle surgery, but were the least likely of all injury types to return to competition (p = 0.044) and were more likely to compete at a lower class (p = 0.026). CLINICAL SIGNIFICANCE: While over half of all dogs returned to competition, just under half of that group decreased jump class. Dogs that have undergone stifle surgery have the worst prognosis for return to agility and if they return, they are more likely to drop class.

Effects of ischemia and the cyclooxygenase inhibitor flunixin on in vitro passage of lipopolysaccharide across equine jejunum.

OBJECTIVE: To determine whether ischemia and flunixin affect in vitro lipopolysaccharide (LPS) absorption in samples of the jejunum of horses. ANIMALS: 12 horses. PROCEDURE: Horses were anesthetized, a midline celiotomy was performed, and the jejunum was located. Two 30-cm sections of jejunum (60 cm apart) were selected. One segment was designated as control tissue; ischemia was induced in the other segment for 120 minutes. Horses were then euthanatized. Mucosa from each jejunal segment was mounted on Ussing chambers and treated with or without flunixin. Tissues from 6 horses were used to assess permeability to radiolabeled LPS; mucosal samples from the remaining 6 horses were incubated with fluorescent-labeled LPS (FITC-LPS) and examined histologically. Production of tumor necrosis factor-alpha (TNF-alpha) and production of LPS-binding protein (LBP) were assessed as indicators of mucosal response to LPS. RESULTS: Ischemia significantly increased mucosal permeability to LPS, but by 180 minutes, the mucosa was not more permeable than control tissue. Flunixin treatment adversely affected intestinal barrier function throughout the experiment but did not result in increased mucosal permeability to LPS. Compared with control tissues, LBP production was increased by ischemia and reduced by exposure to LPS. In ischemic tissue, FITC-LPS entered the lamina propria but TNF-alpha was produced on the mucosal side only, indicating little response to the absorbed LPS. CONCLUSIONS AND CLINICAL RELEVANCE: Ischemia increased LPS passage across equine jejunal mucosa. Flunixin delayed mucosal recovery but did not exacerbate LPS absorption. Evaluation of the clinical importance of flunixin-associated delayed mucosal recovery requires further in vivo investigation.

Effects of flunixin meglumine or etodolac treatment on mucosal recovery of equine jejunum after ischemia.

OBJECTIVE: To examine the effects of flunixin meglumine and etodolac treatment on recovery of ischemic-injured equine jejunal mucosa after 18 hours of reperfusion. ANIMALS: 24 horses. PROCEDURE: Jejunum was exposed to 2 hours of ischemia during anesthesia. Horses received saline (0.9% NaCl) solution (12 mL, i.v., q 12 h), flunixin meglumine (1.1 mg/kg, i.v., q 12 h), or etodolac (23 mg/kg, i.v., q 12 h). Tissue specimens were obtained from ischemic-injured and nonischemic jejunum immediately after ischemia and 18 hours after recovery from ischemia. Transepithelial electric resistance (TER) and transepithelial flux of tritium-labeled mannitol measured mucosal permeability. Denuded villous surface area and mean epithelial neutrophil count per mm2 were calculated. Western blot analysis for cyclooxygenase (COX)-1 and -2 was performed. Pharmacokinetics of flunixin and etodolac and eicosanoid concentrations were determined. RESULTS: Ischemic-injured tissue from horses treated with flunixin and etodolac had significantly lower TER and increased permeability to mannitol, compared with that from horses treated with saline solution. Epithelial denudation after ischemia and 18 hours after recovery was not significantly different among treatments. Both COX-1 and -2 were expressed in ischemic-injured and nonischemic tissues. Ischemia caused significant upregulation of both COX isoforms. Eicosanoid concentrations were significantly lower in tissues from flunixin and etodolac-treated horses, compared with that from horses treated with saline solution. CONCLUSIONS AND CLINICAL RELEVANCE: Flunixin and etodolac treatment retarded recovery of intestinal barrier function in jejunal mucosa after 18 hours of reperfusion, whereas tissues from horses treated with saline solution recovered baseline values of TER and permeability to mannitol.

Evaluation of application of a carpal brace as a treatment for carpal ligament instability in dogs: 14 cases (2008-2011).

OBJECTIVE: To determine whether carpal brace application is a viable treatment for dogs with unilateral carpal ligament instability. DESIGN: Retrospective case series. ANIMALS: 14 client-owned athletic dogs. PROCEDURES: Medical records were reviewed to identify dogs treated with a brace for unilateral carpal valgus or varus instability between August 2008 and August 2011. Treatment included passive motion and isometric strengthening exercises during brace application. RESULTS: Of the 14 dogs, 11 were considered to have returned to normal function; 11 of 12 dogs returned to agility competition. Carpal measurements before treatment indicated the affected limb had significantly greater valgus measurements (median, 30°; range, 30° to 35°), significantly greater varus measurements (median, 15°; range, 15° to 25°), and significantly less flexion (median, 37.5°; range, 30° to 45°), compared with results for the contralateral carpus. Long-term monitoring revealed no differences in measurements between affected and contralateral limbs. Valgus measurements of the affected carpus at brace removal (median, 15°; range, 15° to 20°) and at the end of long-term monitoring (median, 15°; range, 15° to 20°) were significantly lower than measurements before treatment (median, 30°; range, 30° to 35°). Dogs had significantly lower lameness scores (assessed on a scale of 0 to 5) at brace removal (median, 0; range, 0) and at the end of monitoring (median, 0; range, 0 to 2), compared with scores before treatment (median, 3; range, 1 to 3). CONCLUSIONS AND CLINICAL RELEVANCE: Application of a carpal brace resulted in improved stability and resolution or reduction in lameness in dogs with carpal ligament instability.

Computed tomographic anatomy of the equine tarsus.

The purpose of this study was to provide a detailed computed tomographic (CT) anatomic reference for the equine tarsus. CT examinations of the tarsal regions from four clinically and radiographically normal adult horses, which were euthanized for reasons not related to musculoskeletal disease, were included in the study. Limbs were removed at the level of midtibia, and 3-mm contiguous transverse CT images were obtained, starting at a level proximal to the tuber calcanei and continuing distally into the proximal metatarsus. Soft tissue and bone windows were used to image different anatomic features, including bones, joints, and various soft tissue components of the tarsus. Each transverse slice was compared with bone models and dissected specimens to assist in the accurate identification of specific structures. The results of the study consist of nine CT images of the equine tarsus. Each image incorporates labeled soft tissue and bone-window images, a directional compass indicating cranial (Cr) or dorsal (D) and lateral (L), and a reconstructed scout image indicating the level through which the transverse slice was made.