Polydatin Prevents Calcium Pyrophosphate Crystal-Induced Arthritis in Mice.

BACKGROUND: Polydatin is a stilbenoid with important antioxidant, anti-inflammatory, and immunomodulating properties. The aim of this study was to assess the anti-inflammatory preventive effect of polydatin in the mouse model of acute arthritis induced by calcium pyrophosphate (CPP) crystals. METHODS: Acute arthritis was induced by the injection of a suspension of sterile CPP crystals into the ankle joint of Balb/c mice. Animals were randomized to receive polydatin or colchicine (the control drug) according to a prophylactic and a therapeutic protocol. The primary outcome was the variation of ankle swelling obtained after crystal injection and treatment, while histological parameters such as leukocyte infiltration, IL-1ß and CXCL1 levels and tissue expression were considered as secondary outcomes. RESULTS: Prophylactic treatment with PD significantly diminished ankle swelling after 48 h from crystal injection. Secondary outcomes such as leukocyte infiltration, necrosis, edema, and synovitis were also decreased. PD caused a reduction in circulating levels of IL-1ß and CXCL1, as well as their tissue expression. By contrast, the therapeutic administration of PD did not have any beneficial effect. CONCLUSIONS: PD can effectively prevent acute inflammatory response to crystals in the mouse model of CPP crystal-induced arthritis. These results suggest that this bioactive compound might be used in the prevention of crystal-induced acute attacks in humans.

Treatment of Rheumatoid Arthritis by Serum Albumin Nanoparticles Coated with Mannose to Target Neutrophils.

Rheumatoid arthritis (RA) is an angiogenic and chronic inflammatory disease. One of the most extensively used first-line drugs against RA is methotrexate (MTX), but it shows poor solubility, short in vivo circulation, and off-target binding, leading to strong toxicity. To overcome these shortcomings, the present study loaded MTX into nanoparticles of human serum albumin modified with mannose (MTX-M-NPs) to target the drug to neutrophils. MTX-M-NPs were prepared, and their uptake by neutrophils was studied using laser confocal microscopy and flow cytometry. A chick chorioallantoic membrane assay was used to assess their ability to inhibit angiogenesis. The pharmacokinetics and tissue distribution of MTX-M-NPs were investigated using fluorescence microscopy and high-performance liquid chromatography. Their pharmacodynamics was evaluated in a rat model with arthritis induced by collagen. Neutrophils took up MTX-M-NPs significantly better than the same nanoparticles (NPs) without mannose. MTX-M-NPs markedly suppressed angiogenesis in chick embryos, and the MTX circulation was significantly longer when it was delivered as MTX-M-NPs than as a free drug. MTX-M-NPs accumulated mainly in arthritic joints. The retention of NPs was promoted by mannose-derived coating in arthritic joints. Serum levels of inflammatory cytokines, joint swelling, and bone erosion were significantly decreased by MTX-M-NPs. In conclusion, these NPs can prolong the in vivo circulation of MTX and target it to the sites of inflammation in RA, reducing drug toxicity. MTX-M-NPs allow the drug to exert its intrinsic anti-inflammatory, antiangiogenic, and analgesic properties, making it a useful drug delivery system in RA.

Treatment of a large osseous defect in a feline tarsus using a stem cell-seeded custom implant.

The aim of this study is to describe the treatment of an infected segmental bone defect in a cat using a novel, custom-designed titanium implant seeded with adipose-derived stem cells (AdMSCs) to facilitate osseous ingrowth and preserve limb function. Large bone defects occur secondary to trauma, infection, or neoplasia and often result in amputation. We established a novel autologous AdMSC-impregnated trabecular metal spacer made using 3D printing, to bridge the distal tibia and metatarsal bones in the left pelvic limb of a cat that had previously undergone right pelvic limb amputation. Six months postoperatively, there was radiographic evidence of bone growth and implant integration. A titanium spacer seeded with AdMSCs successfully encouraged bone ingrowth in a large defect site and successfully preserved limb function. However, further studies are needed to justify the use of differentiated stem cell impregnated mesh as a framework to bridge large bone defects.

Morphometric measurements to predict meniscal size in skeletally mature dogs for meniscal transplantation.

OBJECTIVE: To determine a relationship between morphometric measurements (MM) and meniscal dimensions (MD) in the dog. STUDY DESIGN: Cadaveric study. ANIMALS: Eighteen mixed-breed canine cadavers (22.35 ± 4.06 kg); 36 each of medial and lateral menisci. METHODS: The following MM were obtained in duplicate: height at scapula, withers, pelvis, rump, and greater trochanter; chest circumference; pelvic circumference; length from occiput to the base of the tail; hock to stifle length (HS); body weight; body condition score; and body fat percentage (BF%). Stifles were disarticulated, and digital photographs of in situ menisci were used to obtain meniscal measurements in duplicate. Morphometric parameters were compared with MD via Pearson correlation (r). A correlation of r ≥ 0.65 was considered strong. RESULTS: The strongest correlation was noted between HS and MD, with r = 0.85 for lateral meniscal width, r = 0.77 for medial meniscal length, and r = 0.76 for medial meniscal width. Lateral meniscal length had the strongest correlation with height at rump (HRu) (r = 0.73). Body weight correlated strongly with meniscal width and fairly with meniscal length. Body condition score and BF% correlated weakly with MD. CONCLUSION: Hock to stifle length was an easily obtainable variable and was proportional to MD. CLINICAL SIGNIFICANCE: Hock to stifle length may be considered by tissue banks and veterinary surgeons as a quick and cost effective screening tool for appropriate meniscal sizing in dogs.

FM0807 decelerates experimental arthritis progression by inhibiting inflammatory responses and joint destruction via modulating NF-κB and MAPK pathways.

BACKGROUND: Rheumatoid arthritis (RA) is a chronic articular synovial inflammatory disease. The precise etiology underlying the pathogenesis of RA remains unknown. We aimed to investigate the inhibitory effect of curcumin analog FM0807 (curcumin salicylate monoester, 2-hydroxy-, 4-[(1E,6E)-7-(4-hydroxy-3-methoxyphenyl)-3,5-dioxo-1,6-heptadien-1-yl]-2-methoxyphenyl ester) on experimental RA and investigate its possible mechanisms of action. METHOD: Rats with Freund's complete adjuvant (FCA)-induced arthritis (AIA) were administered aspirin (0.1 mmol.kg-1), curcumin (0.1 mmol.kg-1), FM0807 (0.1, 0.2 mmol.kg-1) and vehicle via gastric gavage, from days 7 to 21, once daily. The hind paw volume and arthritis index (AI) were measured, and radiographic and histological examinations were performed. Twenty-one days later, the animals were killed and left ankle joints were removed to measure protein expression of the elements of the nuclear factor κB (NF-κB) and mitogen-activated protein kinase (MAPK) pathway by Western blot analysis. The enzyme-linked immunosorbent assay (ELISA) was employed to measure synovial fluid levels of tumor necrosis factor-α (TNF-α), interleukin (IL)-6, IL-1ß and IL-10. RESULTS: Compared with AIA group, FM0807 reduced the AI and swelling of the injected hind paw in a dose-dependent manner, and inhibited increases in inflammatory cell infiltration, pannus formation and cartilage destruction. FM0807 also potently attenuated the increase in the expression of inflammatory factors TNF-α, IL-6 and IL-1ß in synovial fluid, while IL-10 levels were also elevated. FM0807 significantly suppressed phosphorylation of extracellular-signal-regulated kinase (ERK) 1/2 (ERK1/2), c-Jun-N-terminal kinase (JNK) 1/2 (JNK1/2), p38MAPK, inhibitor of NF-κB kinase (IKK), IκB and NF-κB p65 protein, (all P<0.05), which displayed more potential effects compared with those of the aspirin and curcumin groups. CONCLUSION: FM0807 exerts its therapeutic effects on RA by inhibiting cartilage degeneration. FM0807 treatment might be an effective therapeutic approach for RA.

Increased ILC3s associated with higher levels of IL-1ß aggravates inflammatory arthritis in mice lacking phagocytic NADPH oxidase.

The role of redox regulation in immune-mediated arthritis has been previously described. However, the relationship between innate immune cells, including innate lymphoid cells (ILCs) and phagocyte-derived ROS, in this process remains unclear. Here, we characterize ILCs and measure the IL-1 family cytokines along with other cytokines relevant to ILC functions and development in serum-induced arthritic joints in wild type and phagocytic NADPH oxidase (NOX2)-deficient Ncf1-/- mice. We found more severe serum-induced joint inflammation and increased NCR+ ILC3s in inflamed joints of Ncf1-/- mice. Furthermore, in vitro stimulation with IL-1ß on Tbet+ ILC1s from joints facilitated their differentiation into ROR-γt+ ILC3s. Moreover, treatment with IL-1 antagonists effectively lowered the proportions of NCR+ ILC3s and IL-17A producing ILC3s in Ncf1-/- arthritic mice and ameliorated the joint inflammation. These results suggest that NOX2 is an essential regulator of ILC transdifferentiation and may mediate this process in a redox-dependent manner through IL-1ß production in the inflammatory joint. Our findings shed important light on the role of ILCs in the initiation and progression in tissue inflammation and delineate a novel innate immune cell-mediated pathogenic mechanism through which redox regulation may determine the direction of immune responses in joints.

Ankle loading ameliorates bone loss from breast cancer-associated bone metastasis.

Breast cancer is a serious health problem that preferentially metastasizes to bone. We have previously shown that bone loss can be prevented by mechanical loading, but the efficacy of ankle loading for metastasis-linked bone loss has not been investigated. This study showed that body weight was decreased after inoculation of tumor cells, but ankle loading restored a rapid weight loss. The nonloading group exhibited a decrease in bone volume/tissue volume (BV/TV), trabecular thickness, and trabecular number (all P < 0.01) as well as an increase in trabecular separation (P < 0.001). However, ankle loading improved those changes (all P < 0.05). Furthermore, although the nonloading group increased the tumor bearing as well as expression of IL-8 and matrix metalloproteinase 9, ankle loading decreased them. Induction of tumor in the bone elevated the osteoclast number (P < 0.05) as well as the levels of nuclear factor of activated T-cells cytoplasmic 1, NF-κB ligand, cathepsin K, and serum tartrate-resistant acid phosphatase type 5b, but ankle loading reduced osteoclast activity and those levels (all P < 0.05). Tumor bearing was positively correlated with the osteoclast number (P < 0.01) and negatively correlated with BV/TV and the osteoblast number (both P < 0.01). Collectively, these findings demonstrate that ankle loading suppresses tumor growth and osteolysis by inhibiting bone resorption and enhancing bone formation.-Yang, S., Liu, H., Zhu, L., Li, X., Liu, D., Song, X., Yokota, H., Zhang, P. Ankle loading ameliorates bone loss from breast cancer-associated bone metastasis.

[Determination of five cholesterol oxidation products in marinated pig feet and hocks by gas chromatography-mass spectrometry].

An analytical method was developed for the simultaneous determination of five cholesterol oxidation products (COPs) in marinated pig feet and hocks by gas chromatography-mass spectrometry (GC-MS). The five COPs were 7 ß -hydroxycholesterol, cholesterol-5 α,6 α -epoxide, 3 ß,5 α,6 ß -trihydroxycholestane, 25-hydroxycholesterol and 7-ketocholesterol. The sample was extracted with methanol-chloroform (1:2, v/v) and purified by solid phase extraction. Subsequently, the sample was collected for derivatization by N,O-bis(trimethylsilyl)acetamide-trimethyl chlorosilane-1-trimethylsilyllimidazole (3:2:3, v/v/v) (Sylon BTZ). The column temperature was properly programmed, and the selected ion monitoring (SIM) mode was used for the determination of COPs. Under optimum conditions, the five COPs were well separated within 22 min with good separation. The linear range of the five COPs met the requirement of determination, and the average recoveries of the five COPs spiked in the pork samples at three levels were 61.16%-96.96% with relative standard deviations (RSDs) no more than 7.80% (n=3). The limits of detection (LODs) and limits of quantification (LOQs) were in the range of 0.02-47.07 ng/g and 0.06-156.90 ng/g, respectively. This method has a wide line arrange and high sensitivity, and has been successfully applied to the analysis of COPs in actual samples.

Injuries involving the central tarsal bone in nonracing dogs: Short-term outcomes and prognostic factors.

OBJECTIVE: To describe traumatic injuries involving the central tarsal bone (Tc) in nonracing dogs. STUDY DESIGN: Retrospective multicenter study. ANIMALS: Thirty-two client-owned dogs. METHODS: Medical records from January 2010 to December 2016 were searched for dogs with Tc injury. Fracture classification, concurrent tarsal fractures, treatment, and perioperative management were tested for association with postoperative complications and short-term outcome. Outcome measures consisted of the latest lameness score reported in the record. RESULTS: The most common injuries consisted of type V fractures (22) and luxation of the Tc (8). Other injuries included 1 case each of type III and type IV fractures. Twenty-two concurrent fractures involved other tarsal bones. Complications were diagnosed in 18 (62.1%) dogs, consisting of 13 minor, 4 major, and 1 catastrophic complication. Lameness at final follow-up (median 7 weeks) in 28 dogs was scored as 0 of 5 in 14 (50.0%) dogs, 1 of 5 in 7 (25.0%) dogs, 2 of 5 in 4 (14.3%) dogs, 4 of 5 in 1 (3.5%) dogs, and 5 of 5 in 2 (7.1%) dogs. Major complications were associated with the presence of multiple tarsal fractures (risk ratio [RR] 3.94, 95% CI 0.80-19.37, P = .13), specifically when the calcaneus was involved (RR 5.78, 95% CI 1.53-21.88, P = .05). CONCLUSION: The most common diagnosis in this population of nonracing dogs consisted of type V Tc fractures. Fractures affecting other tarsal bones were common and were associated with a higher risk of major complications, especially those affecting the calcaneus. CLINICAL SIGNIFICANCE: Short-term outcomes seem favorable in nonracing dogs with isolated Tc fractures, but dogs with concomitant tarsal fractures are predisposed to major complications.

Functional evaluation outcomes correlate with histomorphometric changes in the rat sciatic nerve crush injury model: A comparison between sciatic functional index and kinematic analysis.

Elucidating whether there is a correlation between biomechanical functions and histomorphometric data in the rat sciatic nerve crush injury model would contribute to an accurate evaluation of the regeneration state without sacrificing animals. The gold standard for functional evaluation is the sciatic functional index (SFI) despite there being intrinsic shortcomings. Kinematic analysis is considered a reliable and sensitive approach for functional evaluation, most commonly assessed as ankle angle at various phases of a gait cycle. Studies utilizing the toe angle for functional evaluation are scarce, and changes in the toe angle following surgery remain unknown. The present study assessed correlations of ankle angle, toe angle and SFI with histomorphometric data, aiming to determine which parameters most accurately reflect changes in histomorphometric data over time. Six Lewis rats were designated as the control group. 30 animals received surgery, six of them were randomly selected on the first, second, third, fourth, and sixth week after surgery for measurements of ankle and toe angles in the "toe-off" phase, and for evaluation of SFI. Histomorphometric analysis were also performed, to determine the number of myelinated nerve fibers, diameters of myelinated nerve fibers, axon diameters, and myelin sheath thicknesses. Furthermore, we investigated changes in ankle angle, toe angle, SFI, and histomorphometric data over time, as well as correlations between ankle angle, toe angle, and SFI with histomorphometric data. The results revealed that changes in SFI, ankle angle, and toe angle highly correlate with histomorphometric data in the rat sciatic nerve crush injury model. Toe angle reflected changes in histomorphometric data with time more precisely than ankle angle or SFI did, and ankle angle was a better prognostic parameter than SFI.

Comparison of hock- and footpad-injection as a prostate adenocarcinoma model in rats.

BACKGROUND: Objective of this study is a feasibility-test comparing hock- and footpad-injection in rats with inoculated MatLyLu - adenocarcinoma tumor model. This study compares the development of an adenocarcinoma model (MatLyLu) in 12 Copenhagen rats. Two groups (n = 6) of animals were inoculated with 1 × 106 MatLyLu tumor cells solved in 0.1 ml NaCl either by footpad or hock injection. All animals were examined before tumor inoculation and before euthanasia using a 3.0 Tesla MRI. Histological evaluation of all organs was performed post mortem. RESULTS: Both types of injection were able to induce the adenocarcinoma model using MatLyLu tumor cells. The primary tumor could be visualized in MRI and confirmed histologically. Comparing the risk of reflux and the maximum injection volume during injection, the hock injection was superior to the footpad injection (less reflux, less anatomical restrictions for larger volumes). The hock injection induces a faster tumor growth compared to the footpad injection. As consequence the maximum level of long term discomfort after hock injection was reached earlier, even if it grew on a not weight bearing structure. Early lymph node tumor metastasis could not be observed macroscopically nor detected histologically. Therefore the reproducibility of the MatLyLu tumor model is questionable. CONCLUSION: Hock injection is a feasible alternative technique compared with footpad-injection in rats. It provides a save and easy injection method for various early-terminated applications with the potential to increase animal welfare during tumor models in rats.

Tyro3/Axl/Mertk-deficient mice develop bone marrow edema which is an early pathological marker in rheumatoid arthritis.

Rheumatoid arthritis is an auto-immune disease of the synovial joints, hallmarked by chronic inflammation and subsequent progressive tissue destruction. TYRO3, AXL and MER (gene name Mertk) (TAM) receptors are part of a negative feedback signaling system in the immune reaction and mediate efferocytosis thereby tempering the inflammatory process. We have shown that Axl-/- and Mertk-/- mice develop more severe arthritis whereas activating these receptors by overexpressing their ligands Pros1 and Gas6 ameliorates arthritis. Mice genetically ablated for the three genes of the TAM receptor family Tyro3/Axl/Mertk (TAM triple knock-out or TKO) have been described to spontaneously develop macroscopic signs of arthritis. In this study we aimed to analyze arthritis development in TAM TKO mice histologically to determine the extent and sequence of pathological changes in the joint. Ankle joints of three different age groups, adolescence (14 weeks), mature adult (34 weeks) and middle-age (52 weeks), of TAM TKO or wild-type mice were examined macroscopically, histologically and immunohistochemically. Surprisingly, until the age of 52 weeks, none of the mice examined developed spontaneous macroscopic signs of arthritis. There was no synovial inflammation nor any signs of damage to the cartilage or bone. However, bone marrow edema was observed in TAM TKO mice in the two latter age groups. The infiltrate in the bone marrow was characterized by both myeloid cells and lymphocytes. This study showed that TAM TKO mice developed a pre-stage (pre-clinical phase) of arthritis marked by bone marrow edema.

Biomechanical evaluation of 6 transarticular tibiotarsal immobilization methods in canine cadaveric limbs.

OBJECTIVE: To determine the effects of 6 types of transarticular immobilization techniques on tibiotarsal joint angles during stimulated weight bearing. STUDY DESIGN: Canine ex vivo biomechanical study. SAMPLE POPULATION: Canine cadaveric pelvic limbs (n = 15). METHODS: A validation study was conducted to determine tibiotarsal flexion before and after transection of the superficial digital flexor tendon in 5 canine cadaveric limbs without tibiotarsal joint immobilization. Six transarticular tibiotarsal immobilization techniques were tested sequentially in 10 canine cadaveric pelvic limbs. The tibiotarsal joint angles were measured from lateral projection radiographs before and during axial loading of 200 N. Mixed linear models were applied to determine the effects of the immobilization techniques on change in tibiotarsal joint angle under loading. RESULTS: There was no change of tibiotarsal joint angle between extended digits and flexed digits under both unloaded and loaded conditions. Change in tibiotarsal joint angles did not differ among any of the immobilization techniques tested here (mean change 1.36°, range 0-5). The main contributor to variance in angle explained by the final model was associated with the random effect for limb. CONCLUSION: Changes in tibiotarsal joint angles during single static loading in canine cadaveric limbs for the 6 immobilization techniques were minimal. CLINICAL SIGNIFICANCE: The 6 techniques appear equally effective at limiting tibiotarsal joint flexion during single axial loading of 200 N. Cyclic mechanical testing of these techniques is recommended to support our findings and validate their clinical application.

High field magnetic resonance imaging contributes to diagnosis of equine distal tarsus and proximal metatarsus lesions: 103 horses.

Injury of the distal tarsus and proximal metatarsus commonly causes lameness. Magnetic resonance imaging (MRI) allows concurrent assessment of both the distal tarsal joints and suspensory ligament origin, and aids identification of lesions that may otherwise go undetected by other modalities. In this retrospective observational study, the medical records of a veterinary imaging center were searched for MRI exams of the distal tarsus and proximal metatarsus for the years 2012 through 2014. Studies for 125 limbs of 103 horses were identified and retrospectively evaluated by two board-certified veterinary radiologists. Soft tissue and osseous changes were characterized and graded by degree of severity. The patients' signalment, lameness severity, and results of diagnostic analgesia were recorded. Osteoarthritic changes of the distal intertarsal and tarsometatarsal joints were the most common findings. Other findings included bone marrow lesions, degenerative changes of the small cuboidal bones, subchondral cystic lesions, and intertarsal desmopathy. Suspensory ligament desmopathy was found in 53% of limbs. Fourty-seven percent of limbs that responded to analgesia of the proximal suspensory ligament had more severe lesions in the distal tarsus. Bone marrow lesions of the third tarsal bone were the only MRI finding that correlated with grade of lameness in patients for which lameness grade was reported. The grade of lameness has a poor correlation with the severity of lesions found on MRI. The findings support the use of MRI for simultaneous evaluation of the proximal metatarsus and distal tarsus, particularly given the difficulty of lesion localization with diagnostic analgesia.

Repair of a Tibiotarsal Fracture in a Pomeranian Goose ( Anser anser) With a Locking Plate.

A 2-year-old Pomeranian goose ( Anser anser) weighing 8.1 kg was examined because of non-weight-bearing lameness of the right limb. A closed, transverse, diaphyseal fracture of the distal third of the right tibiotarsus with a craniolateral displacement of the distal fragment was diagnosed radiographically. Surgery under general anesthesia was performed to repair the fracture with a 14-hole, 2.7-mm locking plate fixed with 6 screws in a bicortical manner. Two days later, the bird was fully weight-bearing on the leg. Radiographs performed 4 and 8 weeks after surgery showed good healing of the affected bone with an appropriate callus formation bridging the fracture line. Sixteen weeks after surgery, the patient was readmitted because of lameness exhibited while staying outside exposed to subzero (°C) temperatures. On the basis of this finding, heat conduction was postulated as the possible cause of lameness because it disappeared after implant removal. To the best our knowledge, this case represents the first report of a surgical repair of a tibiotarsal fracture with a locking plate in waterfowl.

Pantarsal arthrodesis in cats using orthogonal plating.

Case series summary Pantarsal arthrodesis (PTA) was performed in seven tarsi of six cats, using orthogonal (dorsal and medial) veterinary cuttable plates (VCPs) without postoperative external coaptation. Short-term outcomes, arthrodesis progression and complications were assessed using a retrospective review of case notes (veterinary examination) and radiographs. Long-term outcomes were assessed via owner questionnaire (Feline Musculoskeletal Pain Index [FMPI]). Mean angle of PTA was 136° (range 116-166°). Intraoperative complications were recorded in two cases, both involving failure of the drill bit during drilling for calcaneotibial screws. Postoperative complications were encountered in a case of bilateral single-session PTA. These included gastrocnemius myotendinopathy on the right, and long-term protrusion of a screw head from the skin on the left. Both complications were resolved surgically, through resection of the implicated gastrocnemius tendon of insertion and removal of the plate, respectively. FMPI assessment was performed for all six cats a mean of 8.8 months (range 6-16 months) following surgery. Mean score for the first part (assessing ability to perform normal activities) was 92.2% (range 80.9-97.1%). Mean score for the second part (owner perception of pain) was 95.8% (range 87.5-100%). Mean overall score (mean score for parts 1 and 2 combined) was 92.3% (range 81.6-97.4%). PTA may be performed in cats using orthogonal VCPs to treat severe tarsal injuries. It may be prudent to avoid single-session bilateral PTA in cats. Relevance and novel information This case series documents a novel technique as an alternative for PTA in cats with talocrural injuries. Long-term outcome and complications presented in this case series are evaluated and discussed.

Assessment of a novel equine tarsocrural experimental joint disease model using recombinant interleukin-1ß and arthroscopic articular sampling of the medial malleolus of the tibia on the standing sedated horse.

Joint disease and osteoarthritis are common problems in the horse and numerous experimental studies have been developed to determine the safety and efficacy of new therapies. Synovitis, a critical component of joint disease, has been experimentally induced using recombinant interleukin-1 beta (reIL-1ß) to investigate new joint therapies in a controlled environment, although the use of reIL-1ß has not been reported in the equine tarsocrural joint. A common consequence of performing controlled experiments is that articular tissue collection typically requires general anesthesia or euthanasia. This report describes a minimally invasive surgical biopsy technique to harvest joint tissues from the tarsocrural joint in standing horses. The aims of the study were to assess subjective and objective pain parameters following reIL-1ß induced synovitis in the tarsocrural joint and to describe the surgical technique including the location and quantity of tissues obtained with this method. Experimental synovitis was induced using reIL-1ß in one equine tarsocrural joint of each horse using a randomised controlled design. The minimally invasive surgical technique provided sufficient amounts of articular cartilage from the medial malleolus of the tibia and synovium to perform viability, biochemical and histological assessments without necessitating general anesthesia. The minimally invasive technique also allowed for lameness assessment that could have been influenced by more invasive methods of tissue collection. No incisional or lameness complications were detected after use. The synovitis model and surgical technique provided ample tissue for laboratory evaluation and avoided general anesthesia or sacrifice of the horse.

Surgical Management of Osteochondrosis in Foals.

Osteochondrosis is common in young, athletic horses. Some lesions respond to conservative therapy. Surgical management is the mainstay of treatment. Arthroscopic debridement is useful in the femoropatellar joint, tarsocrural joint, fetlock joint, and shoulder joint. Debridement is associated with good outcomes, except in the shoulder joint. Osteochondrosis lesions in the elbow may be difficult to access arthroscopically, thereby transosseous debridement. Surgical management of subchondral cystic lesions of the medial femoral condyle consists of debridement, debridement with grafting, transcondylar screws, and intralesional corticosteroid injection. Surgical management is indicated with lameness and persistent effusion, and in many horses intended for athletic use.

Arthroscopic approach and intra-articular anatomy of the dorsal and plantar synovial compartments of the bovine tarsocrural joint.

OBJECTIVE: To determine arthroscopic approaches to the dorsal and plantar synovial compartments of the tarsocrural joint in adult cattle, and to describe the arthroscopic intra-articular anatomy from each approach. STUDY DESIGN: Ex vivo study. ANIMALS: Fresh adult bovine cadavers (n = 7). METHODS: Two tarsocrural joint were injected with latex to determine arthroscopic portal locations and arthroscopy of the tarsocrural joint of 12 tarsi was performed. The dorsolateral approach was made through the large pouch located between the long digital extensor and peroneus longus tendons. The dorsomedial approach was made just medial to the common synovial sheath of the tibialis cranialis, peroneus tertius, and long digital extensor tendons. The plantarolateral and plantaromedial approaches were made lateral and medial to the tarsal tendon sheath, respectively. RESULTS: Each approach allowed visualization of the distal tibia articulating with the proximal trochlea of the talus. Consistently observed structures included the distal intermediate ridge of the tibia, and the medial and lateral trochlear ridges and trochlear groove of the talus. Lateral and medial malleoli were best assessed from dorsal approaches. From the lateral approaches evaluation of the abaxial surface of the lateral trochlear ridge allowed visualization of the fibulocalcaneal joint. From the plantar approaches additional observed structures included the coracoid process of the calcaneus, plantar trochlea of the talus, and plantar talotibial and talofibular ligaments. CONCLUSION: In cattle, the dorsolateral and plantarolateral approaches allowed for the best evaluation of the dorsal and plantar aspects of the tarsocrural joint, respectively.

Slab fractures of the third tarsal bone: Minimally invasive repair using a single 3.5 mm cortex screw placed in lag fashion in 17 Thoroughbred racehorses.

REASONS FOR PERFORMING THE STUDY: A technique for minimally invasive repair of slab fractures of the third tarsal bone has not previously been reported. Results of third tarsal bone slab fracture repair in Thoroughbred racehorses are lacking. OBJECTIVES: To report the outcomes of repair of uniplanar frontal slab factures of the third tarsal bone using a single 3.5 mm cortex screw in lag fashion. STUDY DESIGN: Retrospective case series. METHODS: Case records of horses that had undergone this procedure were reviewed. RESULTS: Seventeen horses underwent surgery. Eighteen percent of cases had wedge shaped third tarsal bones. A point midway between the long and lateral digital extensor tendons and centrodistal and tarsometatarsal joints created a suitable entry site for implants. The fracture location, configuration and curvature of the third tarsal bone and associated joints requires a dorsolateral proximal-plantaromedial distal trajectory for the screw, which was determined by preplaced needles. There were no complications and fractures healed in all cases at 4-6 months post surgery. Seventy-nine percent of horses returned to racing and, at the time of reporting, 3 are in post operative rehabilitation programmes. CONCLUSION: The technique reported provides a safe, appropriate and repeatable means of repairing slab fractures of the third tarsal bone. Surgical repair is a viable alternative to conservative management.