Cristi R. Cook

Long-term Outcome for Large Meniscal Defects Treated With Small Intestinal Submucosa in a Dog Model

Background Large meniscal defects are a common problem for which current treatment options are limited. Hypothesis Treatment of posterior medial meniscal defects in dogs with small intestinal submucosa is superior to partial meniscectomy in terms of clinical limb function, chondroprotection, and amount and type of new tissue in the defect. Study Design Controlled laboratory study. Methods A total of 51 mongrel dogs underwent medial arthrotomy with creation of standardized meniscal defects. The dogs were divided into groups based on defect treatment: small intestinal submucosa meniscal implant (n = 29) or meniscectomy (n = 22). The dogs were assessed for lameness by subjective scoring after surgery and sacrificed at 3, 6, or 12 months and assessed for articular cartilage damage, gross and histologic appearance of the operated meniscus, amount of new tissue in the defect, equilibrium compressive modulus of meniscal tissue, and relative compressive stiffness of articular cartilage. Results Dogs in the meniscectomy groups were significantly (P <. 001) more lame than dogs treated with small intestinal submucosa. Joints treated with small intestinal submucosa had significantly (P <. 001) less articular cartilage damage, based on india ink staining, than did those treated with meniscectomy. Menisci receiving small intestinal submucosa had more tissue filling in the defects than did menisci receiving no implants, and this new tissue was more mature and meniscus-like and better integrated with remaining meniscus. Conclusion Small intestinal submucosa scaffolds placed in large meniscal defects resulted in production of meniscus-like replacement tissue, which was consistently superior to meniscectomy in amount, type, and integration of new tissue; chondroprotection; and limb function in the long term. Clinical Relevance Small intestinal submucosa implants might be useful for treatment of large posterior vascular meniscal defects in humans.

Clinical Comparison of a Novel Extracapsular Stabilization Procedure and Tibial Plateau Leveling Osteotomy for Treatment of Cranial Cruciate Ligament Deficiency in Dogs

OBJECTIVE To develop and test a novel extracapsular technique, TightRope CCL technique (TR), and compare its 6-month clinical outcomes to tibial plateau leveling osteotomy (TPLO) in dogs with cranial cruciate ligament (CCL) deficiency. STUDY DESIGN Prospective clinical cohort study. ANIMALS Medium, large, and giant breed dogs (n=47) with CCL deficiency. METHODS Before clinical use, TR was evaluated by mechanical testing and the surgical technique was developed and evaluated in canine cadavers. For the clinical study, dogs were assigned to either TR (n=24) or TPLO (n=23) groups and the assigned technique performed after arthroscopic assessment and treatment of joint pathology. Postoperative management was standardized for both groups. Outcome measures were performed immediately postoperatively and up to 6 months after surgery and included complication types and rate, subjective measurement of cranial drawer and tibial thrust, subjective assessment of radiographic progression of osteoarthritis (OA), and function using a validated client questionnaire (6 months only). RESULTS TR with a fiber tape suture had superior mechanical properties for creep, stiffness, yield load, and load at failure. Duration of anesthesia, total surgical time, and stabilization procedure (TR versus TPLO) were all significantly (P<.001) shorter for TR compared with TPLO. Complications requiring further treatment occurred in 12.5% of TR cases and 17.4% of TPLO cases. No significant differences were noted between groups for cranial tibial thrust, but cranial drawer was significantly (P<.05) lower in TR stifles at all postoperative time points. No significant differences were noted between groups for radiographic OA scores. No statistically or clinically significant differences were noted between TR and TPLO for scores for each of the client questionnaire categories. CONCLUSIONS TR resulted in 6-month outcomes that were not different than TPLO in terms of radiographic progression of OA and client-evaluated level of function. TR was associated with shorter anesthesia and surgery times as well as a lower complication rate. CLINICAL RELEVANCE The TR technique is safe and effective and can be considered an appropriate surgical option as part of the overall treatment plan for CCL deficiency in dogs.

Diagnostic imaging of canine elbow dysplasia: a review.

Canine elbow dysplasia (CED) is a common developmental disorder of the cubital joint of dogs. CED is comprised of fragmented medial coronoid process (FMCP), ununited anconeal process (UAP), osteochondrosis (OC), and elbow incongruity. Multiple imaging modalities have been used to assess this complex of disorders and the severity of the pathologic changes. Radiography has been used as a surveying tool for assessment of CED for many years. Recently, alternate techniques and modalities have expanded our knowledge of CED and our clinical approach to this disorder. Nuclear medicine has been used to aid in localizing lameness to the elbow joint. Ultrasonography has proven helpful for imaging the soft tissue structures adjacent to the joint as well as superficial bone abnormalities, including visualization of FMCP. Computed tomography and magnetic resonance imaging are advanced imaging modalities that allow visualization of the elbow in multiple planes and into three-dimensional reconstructions, thus allowing lesions to be more accurately and comprehensively visualized. Assessment of elbow incongruity in particular has been benefitted by these advanced imaging techniques because of the importance of sagittal and dorsal plane imaging and reconstructions for accurately determining the relationships between radial and ulnar articular surfaces. Comparative studies using multiple techniques and imaging modalities with correlation to reference standards and patient outcomes will be vital to continued progress in this area.

Meniscal release in cruciate ligament intact stifles causes lameness and medial compartment cartilage pathology in dogs 12 weeks postoperatively.

OBJECTIVE To evaluate after 12 weeks the effects of caudal medial meniscal release (MR) in the cranial cruciate ligament-intact canine stifle. STUDY DESIGN Blinded, prospective in vivo study. ANIMALS Purpose-bred hound dogs (n=10). METHODS Either MR (n=5) or a sham (SH) surgery (n=5) was performed via arthroscopy. Orthopedic examination and subjective lameness evaluation were performed in each dog preoperatively and at 4, 8, and 12 weeks after surgery. Twelve weeks postoperatively, ultrasonographic, radiographic, and arthroscopic examinations were performed on the operated stifles. Gross pathology of the articular cartilage, cruciate ligaments, and menisci was assessed. India ink staining of the femoral and tibial articular surfaces was performed to determine the percent area of articular cartilage damage. RESULTS At 8 and 12 weeks after surgery, MR dogs were lamer than SH dogs. At 12 weeks, the degree of radiographic OA was significantly higher in MR stifles than in SH stifles. Gross and sonographic meniscal pathology was more severe in MR stifles compared with SH stifles. MR stifles had significantly more severe articular cartilage pathology compared with SH stifles 12 weeks after surgery; pathology was most severe in the medial compartment. CONCLUSIONS MR alone is associated with articular cartilage loss, further meniscal pathology, degenerative joint disease, and lameness. CLINICAL RELEVANCE Subsequent osteoarthritis and dysfunction of the stifle joint should be considered when making clinical decisions regarding MR in dogs.

Effect of high-speed power training on muscle performance, function, and pain in older adults with knee osteoarthritis: A pilot investigation†

To examine the effect of high‐speed power training (HSPT) on muscle performance, mobility‐based function, and pain in older adults with knee osteoarthritis.

Animal models of cartilage repair

Cartilage repair in terms of replacement, or regeneration of damaged or diseased articular cartilage with functional tissue, is the ‘holy grail’ of joint surgery. A wide spectrum of strategies for cartilage repair currently exists and several of these techniques have been reported to be associated with successful clinical outcomes for appropriately selected indications. However, based on respective advantages, disadvantages, and limitations, no single strategy, or even combination of strategies, provides surgeons with viable options for attaining successful long-term outcomes in the majority of patients. As such, development of novel techniques and optimisation of current techniques need to be, and are, the focus of a great deal of research from the basic science level to clinical trials. Translational research that bridges scientific discoveries to clinical application involves the use of animal models in order to assess safety and efficacy for regulatory approval for human use. This review article provides an overview of animal models for cartilage repair. Cite this article: Bone Joint Res 2014;4:89–94.

Prospective Evaluation of Techniques for Differentiating Shoulder Pathology As a Source of Forelimb Lameness in Medium and Large Breed Dogs

OBJECTIVE To assess lameness evaluation, shoulder abduction angles, radiography, and ultrasonography for determining presence, location, and severity of forelimb pathology. STUDY DESIGN Prospective cohort study. ANIMALS Dogs >or=20 kg (n=30). METHODS Each dog was assigned lameness scores. Shoulder abduction angles were determined. Radiographs of shoulders and elbows were subjectively graded for pathology. One investigator unaware of dog history (lameness, radiographic findings) performed ultrasonographic assessment of shoulders with subjective grading of pathology. Another investigator unaware of dog history (lameness, radiographic, ultrasonographic findings) performed arthroscopic assessment of shoulders with subjective grading of pathology. Elbows were disarticulated and evaluated for gross pathology. Histologic pathology scoring of shoulder tissues was performed. Data were compared for differences among groups, sensitivities, specificities, positive and negative predictive values, and positive and negative likelihood ratios were calculated. RESULTS Twenty-seven forelimbs were considered clinically normal, 26 had shoulder pathology, 5 had elbow pathology, and 2 had pathology of both the shoulder and elbow. Dogs with shoulder pathology were twice as likely to be lame compared with dogs with elbow pathology. Limbs with medial shoulder instability had significantly higher abduction angles than normal limbs and those with elbow pathology. Radiographs were clinically useful for diagnosing elbow, but not shoulder, pathology. Ultrasonography was clinically useful for diagnosing shoulder pathology other than instability. Abduction angles, ultrasonographic evaluation, and arthroscopic assessments had strong, significant correlations with reference standards. CONCLUSIONS Clinically relevant diagnostic techniques yielded characteristic, repeatable differences in objective and subjective assessments for distinguishing presence, location, and severity of forelimb lameness in dogs. CLINICAL RELEVANCE The diagnostic approach to forelimb lameness in dogs should include shoulder pathology as a differential with multiple assessments used to determine the clinical cause of lameness.

Kartagener’s Syndrome in a Dachshund Dog

Kartageners syndrome (KS) is a rare, congenital condition characterized by situs inversus, rhinosinusitis, and bronchiectasis. An underlying ciliary dysfunction (e.g., immotility or dyskinetic beating) produces most of the clinical signs seen in affected animals. This case report reviews the history, clinical signs, and diagnosis of KS in a male, long-haired dachshund. This is the first known report of KS, and thus primary ciliary dyskinesia, in this breed of dog.

Multiple injections of leukoreduced platelet rich plasma reduce pain and functional impairment in a canine model of ACL and meniscal deficiency

Platelet rich plasma (PRP) is used to treat many musculoskeletal disorders. We used a canine model to determine the effects of multiple intra‐articular injections of leukoreduced PRP (ACP) on anterior cruciate ligament healing, meniscal healing, and progression of osteoarthritis (OA). With Animal Care and Use Committee (ACUC) approval, 12 dogs underwent partial ACL transection and meniscal release in one knee. At weeks 1, 2, 3, 6, and 8 after insult, dogs were treated with intra‐articular injections (2 ml) of either ACP (n = 6) or saline (n = 6). Dogs were assessed over 6 months to determine comfortable range of motion (CROM), lameness, pain, effusion, kinetics, and radiographic and arthroscopic assessments. At 6‐month endpoint, dogs were assessed for ACL material properties and histopathology. Saline‐treated dogs had significantly (p < 0.04) more CROM loss, significantly (p < 0.01) more pain, significantly (p < 0.05) more severe lameness, significantly (p < 0.05) lower function, and significantly (p < 0.05) lower %Total Pressure Index in affected hindlimbs compared to ACP‐treated dogs. Radiographic OA increased significantly (p < 0.01) over time within each group. Arthroscopically, saline‐treated knees showed moderate to severe synovitis, further ACL disruption, and medial compartment cartilage loss, and ACP‐treated knees showed evidence of ACL repair and less severe synovitis. ACL material properties in ACP‐treated knees were closer to normal than in saline‐treated knees, however, the differences were not statistically significant. ACL histopathology was significantly (p< 0.05) less severe in ACP‐treated knees compared to saline‐treated knees. Five intra‐articular injections of leukoreduced PRP had beneficial effects for ACL healing, improved range of motion, decreased pain, and improved limb function for up to 6 months in this model.

In Vivo Toxicity of Local Anesthetics and Corticosteroids on Chondrocyte and Synoviocyte Viability and Metabolism.

Objective: Intra-articular injection of local anesthetic and/or corticosteroid is an adjunct treatment for arthritic and inflammatory orthopedic conditions. Despite potential benefits, there is growing concern that these medications may cause significant morbidity, including potential toxicity to intra-articular chondrocytes and synoviocytes. Design: Twenty dogs underwent intra-articular injection of the shoulder joint using ultrasound guidance, with the following injectates (n = 5 each): negative control (saline), methylprednisolone/1.0% lidocaine, triamcinolone/1.0% lidocaine, and triamcinolone/0.0625% bupivacaine. The dogs were euthanized 24 hours postinjection for reasons unrelated to this study. Synovium/cartilage explants were harvested under sterile conditions and assessed immediately or cultured for 7 days. Synoviocyte and chondrocyte viability was determined on day 1 and day 7 using Calcien AM and Sytox Blue live/dead fluorescent stains, and cell metabolism determined on day 2 using the alamar blue additive test. Results were compared statistically. Results: On day 1 synovium exposed to 1%L/M demonstrated a significant decrease in cell metabolism (P = 0.0107) and subjective synoviocyte viability scores (P = 0.013) compared with the negative control. Cartilage exposed to 1%L/M demonstrated decreased chondrocyte viability and cell metabolism versus all other groups, although not significantly. After 7 days of culture, cartilage viable cell density in the 1%L/M group was significantly (P ≤ 0.001) lower than the negative control. Subjective synoviocyte viability scores was significantly lower in the 1%L/M (P = 0.013), 1%L/T (P ≤ 0.001), and 0.0625%B/T groups (P = 0.006) compared with the negative control. Conclusions: This study suggests potential negative effects of combination local anesthetic/corticosteroid on intra-articular cell viability and cell metabolism. Further study is needed before determining definitive clinical recommendations.