Patient specific, synthetic, partial unipolar resurfacing of a large talar osteochondritis dissecans lesion in a dog.

OBJECTIVE: To describe the application and early outcome of a custom-made unipolar partial tarsal replacement in a dog with an extensive medial talar ridge OCD. ANIMAL: A 7-month-old, 25 kg male Rhodesian Ridgeback with progressive left hindlimb lameness (grade III-IV/IV) and diagnosis of talar OCD. METHODS: The dog presented with progressive lameness attributed to extensive medial talar ridge OCD. Due to the severity of the lesion, a resurfacing procedure was chosen. Based on CT data, a bi-layered resurfacing implant consisting of a titanium socket and a polycarbonate urethane bearing surface was constructed. For intraoperative guidance, a set of matching drill guides were 3D-printed, along with some models of the affected talus, to allow for dry-lab training. Surgical implantation using a medial malleolar osteotomy to approach the lesion was without complications. Orthopedic follow-up examinations were conducted at 10 days, 4 weeks, 6 weeks, 6 months and 12 months. Radiographic examinations were included at the 6-week, 6-month, and 12-month follow-ups. RESULTS: Function improved considerably during the follow-up period with a lameness grade of 0-I/IV at the 12-month follow-up. ROM differed by 15° in flexion compared to the contralateral side, while there was no difference in extension. Moderate periarticular fibrosis was present at 12 months. Implant positioning was unchanged at follow-up-radiographic examination and there was only mild progression of osteoarthritis (OA). CONCLUSION: Patient specific instrumentation - guided tarsal OCD resurfacing with a synthetic patient-specific implant may be an effective treatment option.

Cyclic tensile tests of Shetland pony superficial digital flexor tendons (SDFTs) with an optimized cryo-clamp combined with biplanar high-speed fluoroscopy.

BACKGROUND: Long-term cyclic tensile testing with equine palmar/plantar tendons have not yet been performed due to problems in fixing equine tendons securely and loading them cyclically. It is well established that the biomechanical response of tendons varies during cyclic loading over time. The aim of this study was to develop a clamping device that enables repetitive cyclic tensile testing of equine superficial digital flexor tendon for at least 60 loading cycles and for 5 min. RESULTS: A novel cryo-clamp was developed and built. Healthy and collagenase-treated pony SDFTs were mounted in the custom-made cryo-clamp for the proximal tendon end and a special clamping device for the short pastern bone (os coronale). Simultaneously with tensile testing, we used a biplanar high-speed fluoroscopy system (FluoKin) to track tendon movement. The FluoKin system was additionally validated in precision measurements. During the cyclic tensile tests of the SDFTs, the average maximal force measured was 325 N and 953 N for a length variation of 2 and 4 % respectively. The resulting stress averaged 16 MPa and 48 MPa respectively, while the modulus of elasticity was 828 MPa and 1212 MPa respectively. Length variation of the metacarpal region was, on average, 4.87 % higher after incubation with collagenase. The precision of the FluoKin tracking was 0.0377 mm, defined as the standard deviation of pairwise intermarker distances embedded in rigid bodies. The systems accuracy was 0.0287 mm, which is the difference between the machined and mean measured distance. CONCLUSION: In this study, a good performing clamping technique for equine tendons under repetitive cyclic loading conditions is described. The presented cryo-clamps were tested up to 50 min duration and up to the machine maximal capacity of 10 kN. With the possibility of repetitive loading a stabilization of the time-force-curve and changes of hysteresis and creep became obvious after a dozen cycles, which underlines the necessity of repetitive cyclical testing. Furthermore, biplanar high-speed fluoroscopy seems an appropriate and highly precise measurement tool for analysis of tendon behaviour under repetitive load in equine SDFTs.

Long-term effects of tibial plateau leveling osteotomy and tibial tuberosity advancement on tibial plateau subchondral bone density in dogs.

OBJECTIVE: To evaluate long-term loading patterns using subchondral bone density (SBD) distribution of the tibial plateau after tibial plateau leveling osteotomy (TPLO) and tibial tuberosity advancement (TTA). STUDY DESIGN: Cross-sectional study. ANIMALS: Adult (> 2 years), medium to large breed dogs (>20 kg) that had been treated with TPLO or TTA at least 1 year prior to the study were recruited. A normal cohort of similar age and weight dogs with normal physical and orthopedic examinations served as control. METHODS: Dogs were sedated for computed tomography (CT) of the stifle, and DICOM (digital imaging and communications in medicine) files were processed for CT osteoabsorptiometry (CTOAM). Tibial plateaus were sampled at 6 zones, and CTOAM was used to determine regional and maximal areas of SBD as a marker of joint loading. RESULTS: Data were collected on 48 stifles in 31 dogs (15 TPLO, 11 TTA, 22 control). Lower Hounsfield unit (HU) values were measured in the caudal and mid-region of the lateral tibial plateau after TPLO and compared to normal. HU values did not differ between joints treated with TTA and those in the control group. CONCLUSION: TPLO may alter stifle load distribution relative to the normal control group. There were no differences between TTA and the control group. CLINICAL SIGNIFICANCE/IMPACT: Despite ongoing osteoarthritis (OA) in dogs after surgical intervention for cranial cruciate disease, changes in tibial SBD are minor and may not correlate with clinical function.

Two-Way Radio Modem Data Transfer for Newborn Hearing Screening Devices.

INTRODUCTION: The success of a newborn hearing screening program depends on successful tracking and follow-up to ensure that children who have had positive screening results in the first few days of life receive appropriate and timely diagnostic and intervention services. The easy availability, through a suitable infrastructure, of the data necessary for the tracking, diagnosis, and care of children concerned is a major key to enhancing the quality and efficiency of newborn hearing screening programs. MATERIALS AND METHODS: Two systems for the automated two-way transmission of newborn hearing screening and configuration data, based on mobile communication technology, for the screening devices MADSEN AccuScreen® and Natus Echo-Screen® were developed and tested in a field study. Radio modem connections were compared with conventional analogue modem transmissions from Natus Echo-Screen devices for duration, transmission rate, number of lost connections, and frequency of use. RESULTS: The average session duration was significantly lower with the MADSEN AccuScreen (12 s) and Natus Echo-Screen both with radio modem (15 s) than the Natus Echo-Screen with analogue modem (108 s). The transmission rate was significantly higher (898 and 1,758 vs. 181 bytes/s) for the devices with radio modems. Both radio modem devices had significantly lower rates of broken connections after initial connection (2.1 and 0.9 vs. 5.5%). An increase in the frequency of data transmission from the clinics with mobile radio devices was found. CONCLUSIONS: The use of mobile communication technology in newborn hearing screening devices offers improvements in the average session duration, transmission rate, and reliability of the connection over analogue solutions. We observed a behavioral change in clinical staff using the new technology: the data exchange with the tracking center is more often used. The requirements for on-site support were reduced. These savings outweigh the small increase in costs for the Internet service provider.

Prospective Evaluation of the Leipzig Stifle Distractor.

OBJECTIVES: To evaluate the Leipzig Stifle Distractor (LSD) for arthroscopic evaluation of the medial meniscus. STUDY DESIGN: Prospective clinical multi-center study. ANIMALS: 64 stifles of 64 dogs (mean body weight 35 kg) with suspected cranial cruciate ligament rupture. METHODS: The LSD was used to distract the medial compartment and to evaluate the medial meniscus. The degree of exposure of the caudal pole of the medial meniscus (CMM) and ease of diagnosis was quantified after either distraction with the LSD or manipulation of the stifle with valgus stress and external rotation. Time for pin placement, level of difficulty and associated complications with LSD application were recorded. Medial collateral ligament integrity was tested by stress radiographs. RESULTS: The mean time for applying the LSD was 1.4 minutes (range 0.5-3.0). Application was considered easy in 90% and moderate in 10% of joints, with no complications recorded. LSD application increased exposure (P < .001) and facilitated probing of the CMM (P < .001), allowing for the diagnosis of 10 meniscal tears missed without the LSD. The use of LSD increased the likelihood of diagnosing a meniscal tear by 1.9 times. Based on the stress radiographs, medial collateral ligament integrity was maintained in all tested stifles. CONCLUSION: Diagnosis of medial meniscal tears was improved using LSD. The LSD provided a safe and effective method for improved visualization and access to the caudal portion of the medial meniscus, which may allow for better arthroscopic assessment of meniscal pathology in dogs.

Relationship between axial radioulnar incongruence with cartilage damage in dogs with medial coronoid disease.

OBJECTIVE: To quantify axial radioulnar incongruence (aRUI) in dogs with simple fragmented medial coronoid process (FCP) and those with advanced medial coronoid disease (MCD). STUDY DESIGN: Retrospective clinical study. SAMPLE POPULATION: Group 1: 54 elbow joints (54 dogs) with FCP, but no other visible cartilage damage. Group 2: 32 elbows (32 dogs) with Outerbridge grade 3-4 cartilage pathology of the medial coronoid ± FCP. METHODS: aRUI was quantified using CT based 3D models of the radioulnar joint cup. A sphere was fitted to the trochlear notch of each of the 3D models and aRUI estimated in millimeters based on the relation of the sphere and the radial joint surface. Coronoid disease was diagnosed, classified, and graded using arthroscopy. RESULTS: Mean (±SD) aRUI for group 1 (0.2 ± 0.8 mm) was significantly less than in group 2 (0.8 ± 0.9 mm; P = .001). Overall, 14% had negative aRUI whereas 40% were congruent. Stepwise logistic regression analysis identified age and aRUI, but not body weight as significant covariates. The corresponding odds ratios for advanced MCD were 1.6 for age and 6.4 for RUI, respectively. CONCLUSION: Axial RUI is greater and more prevalent in elbows with severe cartilage disease, and consists most commonly of a short radius.

Neurologic outcome after thoracolumbar partial lateral corpectomy for intervertebral disc disease in 72 dogs.

OBJECTIVE: To determine neurologic outcome and factors influencing outcome after thoracolumbar partial lateral corpectomy (PLC) in dogs with intervertebral disc disease (IVDD) causing ventral spinal cord compression. STUDY DESIGN: Retrospective case series. ANIMALS: Dogs with IVDD (n = 72; 87 PLC). METHODS: Dogs with IVDD between T9 and L5 were included if treated by at least 1 PLC. Exclusion criteria were: previous spinal surgery, combination of PLC with another surgical procedure. Neurologic outcome was assessed by: (1) modified Frankel score (MFS) based on neurologic examinations at 4 time points (before surgery, immediately after PLC, at discharge and 4 weeks after PLC); and (2) owner questionnaire. The association of the following factors with neurologic outcome was analyzed: age, body weight, duration of current neurologic dysfunction (acute, chronic), IVDD localization, breed (chondrodystrophic, nonchondrodystrophic), number of PLCs, degree of presurgical spinal cord compression and postsurgical decompression, slot depth, presurgical MFS. Presurgical spinal cord compression was determined by CT myelography (71 dogs) or MRI (1 dog), whereas postsurgical decompression and slot depth were determined on CT myelography (69 dogs). RESULTS: MFS was improved in 18.7%, 31.7%, and 64.2% of dogs at the 3 postsurgical assessments, whereas it was unchanged in 62.6%, 52.8%, and 32.0% at corresponding time points. Based on owner questionnaire, 91.4% of dogs were ambulatory 6 months postsurgically with 74.5% having a normal gait. Most improvement in neurologic function developed within 6 months after surgery. Presurgical MFS was the only variable significantly associated with several neurologic outcome measurements (P < .01). CONCLUSIONS: PLC is an option for decompression in ventrally compressing thoracolumbar IVDD. Prognosis is associated with presurgical neurologic condition.

Cubital subchondral joint space width and CT osteoabsorptiometry in dogs with and without fragmented medial coronoid process.

OBJECTIVE: To evaluate subchondral joint space width measurements (SJSW) and CT-osteoabsorptiometry (CTOAM) measurements in the elbow of dogs with naturally occurring fragmented medial coronoid process (FMCP) preoperatively and 6 months postoperatively, and to compare these to normal dogs. STUDY DESIGN: Prospective randomized clinical trial. ANIMALS: Large breed dogs <1 year of age (n = 15). METHODS: Arthroscopic FMCP debridement was performed, followed by randomization to a proximal ulnar ostectomy with IM pin (PUO). CTs were performed pre-operatively and 6 months post-operatively. CTOAM and SJSW measurements were acquired in 7 locations within the joint and compared to an age-matched normal control group. Pearson correlation was performed on SJSW and CTOAM measurements. A linear mixed model determined the effect of disease and treatment on SJSW and CTOAM measurements. RESULTS: Fifteen dogs (28 elbows) with FMCP participated (11 arthroscopic FMCP removal, 17 with additional PUO). Data were normally distributed. Pearson correlation between CTOAM and SJSW measurements showed moderate to strong negative correlation in the control dogs. Preoperatively, affected elbows had lower medial compartment and higher lateral coronoid process CTOAM values than normal elbows. After treatment, CTOAM values of the medial compartment increased to normal. Treatment with PUO did not affect SJSW or CTOAM. CONCLUSIONS: Our data agree with these previous studies suggesting lower subchondral plate mineralization in dogs affected by FMCP. Arthroscopy may result in higher CTOAM values secondary to increased loading.

Evaluation of the Effects of an Undenatured Collagen Type-2-Based Nutraceutical (ARTHROSHINE® HA²) on Recovery Time after TPLO in Dogs: A Prospective, Randomized Study with Objective Gait Analysis as the Primary Outcome Measure.

This randomized, prospective clinical trial investigates the impact of a novel undenatured collagen type 2 (T2NDC)-based nutraceutical, ARTHROSHINE® HA² (AS), on postoperative rehabilitation following Tibial Plateau Leveling Osteotomy (TPLO) in 50 dogs with unilateral cranial cruciate ligament rupture (CCLR). The patients were randomly allocated to either group A, receiving AS once daily for 24 weeks post-TPLO surgery, or group B, without any supplementation. Frequency matching was applied to enhance group comparability. Assessment of outcomes included computerized gait analysis and a validated owner questionnaire. AS supplementation was well received, without any reported side effect. Consistently, patients in group A exhibited significantly higher peak vertical force values during all follow-up assessments. By the 12-week mark, gait analysis indicated a return to a physiological gait pattern in group A, while group B achieved this normalization only by the 24-week point. The administration of AS post-TPLO surgery demonstrates promise in enhancing limb function, leading to faster restoration of a physiological gait pattern. The inclusion of AS, a T2NDC-based nutraceutical, in the post-TPLO rehabilitation protocol may contribute to improved limb function and an expedited recovery, potentially facilitating a quicker return to normalcy. It is noteworthy that subjective owner perceptions did not differ between the two groups.

Estimation of joint incongruence in dysplastic canine elbows before and after dynamic proximal ulnar osteotomy.

OBJECTIVE: To characterize joint incongruence in dysplastic canine elbows before and after dynamic proximal ulnar osteotomy (DPUO). STUDY DESIGN: Clinical, prospective study. ANIMALS: Dogs (n = 10; 12 elbows) with ≥ 2 mm radioulnar incongruence (RUI), FCP, and/or OCD. METHODS: Computed tomography in a nonload bearing position was used to generate in silico 3D models of the elbow joint before DPUO, and this was repeated after DPUO union (median 3 months postoperatively). On these models, RUI, humeroradial and humeroulnar subchondral joint space width (SJSW) as well as alignment of the proximal ulnar segment were investigated. RESULTS: RUI at the medial coronoid process (MCP) decreased (P = .001), while it increased at the lateral coronoid process (P = .0005), and remained unchanged at the level of the trochlear ridge (P = .25). SJSW at the MCP increased (P = .001), changing from focal joint space collapse preoperatively to a more homogeneous pattern of moderate SJSW at follow-up. The proximal ulnar segment rotated in all 3 planes with caudal tipping at the level of the osteotomy and varus deformity, while no axial translation could be noted. CONCLUSIONS: DPUO results in reduction of RUI and amelioration of focal contact area at the MCP. This effect is the result of a complex three-dimensional rotation of the proximal ulnar segment, rather than axial shift.

Sensitivity and specificity of 3D models of the radioulnar joint cup in combination with a sphere fitted to the ulnar trochlear notch for estimation of radioulnar incongruence in vitro.

OBJECTIVE: To determine the sensitivity and specificity of estimation of radioulnar incongruence (RUI) by use of 3-dimensional (3D) image renderings in combination with a sphere fitted to the ulnar trochlear notch. STUDY DESIGN: In vitro study. SAMPLE POPULATION: Right forelimbs (n = 8) of canine cadavers weighing >20 kg. METHODS: CT-based 3D models (n = 63) of the radioulnar joint cup with different states of RUI were used. A sphere was fitted to the trochlear notch of each of the models and 2 independent observers estimated RUI based on the relation of the sphere and the radial joint surface blinded to the true state of RUI at 1 mm precisely (-2 mm to +2 mm). RESULTS: Mean sensitivity and specificity for detecting any form of incongruent joint was 0.94 and 0.89, respectively. Evaluating a positive step (short radius) versus a congruent joint resulted in a mean sensitivity and specificity of 0.89 and 0.96, respectively. A negative RUI (short ulna) was diagnosed with a mean sensitivity and specificity of 1.00 and 0.92, respectively. Intra-class-correlation coefficient for inter-observer agreement was 0.99. CONCLUSIONS: Fitting a sphere to the ulnar trochlea notch significantly improves diagnostic accuracy of 3D models of the radioulnar joint cup when diagnosing RUI.

Effect of ventral slot procedure on spinal cord compression in dogs with single static intervertebral disc disease: preliminary findings while evaluating a semiquantitative computed tomographic myelographic score of spinal cord compression.

OBJECTIVE: To (1) evaluate pre- and postoperative cervical spinal cord compression (SCC) in the context of uncomplicated ventral slot (VS) decompression using computed tomographic (CT) myelography and (2) report reliability of a semiquantitative SCC score using CT myelography. STUDY DESIGN: Prospective and retrospective, clinical pilot study. ANIMALS: Dogs (n = 17) with single static intervertebral disc disease. METHODS: On matched pre- and postoperative transverse CT myelographic images, degree and lateralization of extradural SCC were scored by 4 blinded independent observers, followed by consensus finding. Inter- and intraobserver variability was quantified using intraclass correlation (ICC). Nonparametric tests were performed comparing pre- and postoperative SCC, correlation with neurologic status and significance of lateralization. RESULTS: Because of invisible contrast agent, only 13 dogs could be fully evaluated. After VS, SCC was significantly reduced whereas neurologic function significantly improved. Ten dogs had residual compression, not affecting neurologic long-term outcome. Only preoperative compression score and neurologic status 3-7 weeks postoperatively were inversely correlated. Lateralization of SCC preoperatively did not affect postsurgical compression scores. Interobserver ICC was 0.848 and intraobserver ICC was 0.984. CONCLUSIONS: VS improves neurologic function but often fails at completely resolving extradural SCC. The proposed CT myelographic score is highly reliable, assuring consistency among and within observers.

Mapping Subchondral Bone Density Distribution in the Canine C6-C7 Vertebral Endplates: A CT-OAM Study.

Intervertebral cage subsidence is a common complication in treating disc-associated cervical spondylomyelopathy in dogs. The mechanical stability of the vertebral endplate in contact with the cage is crucial to preventing subsidence. This study aims to assess subchondral bone mineral density (sBMD) in the canine vertebral endplate (specifically, the C6-C7 vertebral motion unit) as a measure of its mechanical stability. The sBMD distribution was mapped for the C6 caudal and C7 cranial vertebral endplates in 15 middle- to large-breed dogs using computed tomography osteoabsorptiometry. The sBMD distribution in the canine C6 and C7 vertebral endplates exhibited a heterogeneous pattern, with lower density observed in the central and dorsal contact areas of the nucleus pulposus, where common subsidence occurs. Our results suggest a potential need to redesign intervertebral cages to ensure that contact areas align with regions of higher bone density. A broad-based design extending toward the lateral and dorsal aspects of the annulus fibrosus contact area may enhance stability.

Quantification of skin wound tension using a newly designed wound tensiometer.

OBJECTIVE: To (i) quantitatively measure wound tension in experimental skin wounds using a newly developed wound tensiometer and (ii) establish reference values for primary skin wound closure in medium- and large-breed dogs. STUDY DESIGN: Experimental cadaveric study. ANIMAL POPULATION: Nineteen dogs of medium to large breeds (BW 20 to 40 kg). METHODS: Elliptical skin wounds of different sizes were created on the chest and abdomen. The wounds were gradually enlarged. Experienced surgeons (ECVS diplomates or professors of small animal surgery) and inexperienced surgeons (1st year after graduation) independently assessed wound tension through manual manipulation and determined whether the wound could be closed without tension-relieving measures. In addition, wound tension was objectively quantified using a newly developed wound tensiometer. RESULTS: The upper threshold for wound tension at which direct appositional wound closure was recommended by the experienced surgeons was 5.4 N, and the median minimal tension without recommendations for closure was 6.0 N. The data also demonstrate that wound tension and wound size do not necessarily correlate, and inexperienced surgeons need to develop a feel for wound tension. CONCLUSION: The intraoperative use of the wound tensiometer, in combination with established cut-off values, might facilitate decision-making regarding primary wound closure. CLINICAL RELEVANCE: The findings of this study provide evidence for the applicability of a wound tensiometer in guiding inexperienced surgeons in their choice of the skin wound closure method.

Continuous hemilaminectomy of nine vertebrae can be performed safely in large breed dogs: A case report of a German Shepherd Dog with intervertebral disc extrusion and extensive extradural hemorrhage.

Background: Extended, continuous hemilaminectomy has only been reported in small to medium-sized dogs so far. It remains unclear whether excessive continuous hemilaminectomy can also be performed safely in large breed dogs. Case Description: We describe the surgical treatment and clinical outcome of a 5-year-old German Shepherd Dog that presented with paraplegia and deep pain perception following a short episode of bilateral hind-limb lameness, secondary to jumping off of a car. Computed tomography-myelography revealed that the paraplegia originated from extensive extradural spinal cord compression (Th6-L1), due to intervertebral disc extrusion and associated epidural hemorrhage. The dog was treated with a continuous hemilaminectomy involving nine vertebrae (Th6-L1) and recovered completely with no remaining neurological deficits, within 6 months. Conclusion: The rapid, uncomplicated, and complete functional recovery in the presented case emphasizes the practicability of extensive, continuous hemilaminectomies, also in large breed dogs.

Partial lung lobectomy with the Caiman® Seal & Cut device in a dog with spontaneous pneumothorax: Case report.

Background: Spontaneous pneumothorax in dogs is characterized by an accumulation of air in the interpleural space without underlying trauma and consecutive acute onset of respiratory distress. Underlying causes for spontaneous pneumothorax vary with ruptured bullae being one of the main causes. Treatment after initial stabilization often requires partial or complete surgical resection of affected lung lobes. Partial lung lobectomy can be performed with stapling devices or sealing devices for example, by different surgical approaches including video-assisted thoracoscopic surgery. However, inter-thoracic surgery in small-sized dogs using either of the techniques is challenging. Case Description: A 12-year-old Shih Tzu was presented with spontaneous pneumothorax. Further diagnostics with computed tomography and intercostal thoracoscopy revealed a bulla in the right middle lung lobe. Partial lung lobectomy (2.5 × 2.5 × 2 cm) of the respective lung lobe was performed by an intercostal approach using the Caiman® 5 Seal & Cut sealing device. The Caiman® 5 Seal & Cut device allowed quick and safe partial lung lobectomy in the treatment of spontaneous pneumothorax without intra- or post-operative complications. The dog was discharged 2 days after surgery in good clinical condition. This report demonstrates the in-vivo efficacy and safety of the Caiman® 5 Seal & Cut sealing device for partial lung lobectomy in a small breed dog. Conclusion: Using the Caiman® 5 Seal & Cut device lung tissue could be resected without intra- or post-operative complications in a small breed dog. This case may emphasize the use of the device in fully video-assisted thoracoscopic surgery also in small-sized patients.

Topographic and age-dependent distribution of subchondral bone density in the elbow joints of clinically normal dogs.

OBJECTIVE: To investigate topographic and age-dependent adaptation of subchondral bone density in the elbow joints of healthy dogs by means of computed tomographic osteoabsorptiometry (CTOAM). Animals-42 elbow joints of 29 clinically normal dogs of various breeds and ages. PROCEDURES: Subchondral bone densities of the humeral, radial, and ulnar joint surfaces of the elbow relative to a water-hydroxyapatite phantom were assessed by means of CTOAM. Distribution patterns in juvenile, adult, and geriatric dogs (age, < 1 year, 1 to 8 years, and > 8 years, respectively) were determined and compared within and among groups. RESULTS: An area of increased subchondral bone density was detected in the humerus distomedially and cranially on the trochlea and in the olecranon fossa. The ulna had maximum bone densities on the anconeal and medial coronoid processes. Increased bone density was detected in the craniomedial region of the joint surface of the radius. A significant age-dependent increase in subchondral bone density was revealed in elbow joint surfaces of the radius, ulna, and humerus. Mean subchondral bone density of the radius was significantly less than that of the ulna in paired comparisons for all dogs combined and in adult and geriatric, but not juvenile, dog groups. CONCLUSIONS AND CLINICAL RELEVANCE: An age-dependent increase in subchondral bone density at the elbow joint was revealed. Maximal relative subchondral bone densities were detected consistently at the medial coronoid process and central aspect of the humeral trochlea, regions that are commonly affected in dogs with elbow dysplasia.

Partial lateral corpectomy of the thoracolumbar spine in 51 dogs: assessment of slot morphometry and spinal cord decompression.

OBJECTIVE: To report slot morphometry, degree of spinal decompression, and factors influencing decompression after partial lateral corpectomy (PLC) of the thoracolumbar spine in dogs with intervertebral disc disease. STUDY DESIGN: Case series. ANIMALS: Dogs (n=51) with predominantly ventrally located spinal cord compression. METHODS: PLC (n=60) were performed. Spinal cord compression was determined by computed tomographic (CT) myelography (n=46), myelography (n=2) or magnetic resonance imaging (n=3). Postsurgical CT images were used to evaluate slot dimensions and orientation, and spinal cord decompression. The influence of age, body weight, breed, breed type (chondrodystrophic, nonchondrodystrophic), disc location, lateralization and mineralization, presurgical compression, slot morphometry, and surgeon on degree of decompression were evaluated. RESULTS: Mean slot depth was 64.1% of vertebral body width; mean height, 43.0% of vertebral body height; mean cranial extension, 29.5%; median caudal extension, 22.0% vertebral body length; mean angulation from horizontal, 6.3°. Decompression was satisfactory in 90% of sites after PLC (58% complete, 32% good). None of the analyzed factors significantly influenced decompression. All lumbar spine PLC resulted in complete or good decompression compared with 83% after thoracic PLC (P=.052). Deeper slots tended to allow more complete decompression (P=.058). CONCLUSIONS: Thoracolumbar PLC results in satisfactory decompression in most cases with a better outcome in the lumbar spine than the thoracic spine. Achieving a slot depth equal to 2/3 of vertebral body width might facilitate complete decompression.

Relation of Computed Tomography-Based Static Axial Radioulnar Incongruence Measurements under General Anaesthesia and Dynamic, In Vivo RUI during the Walk in Canine Elbow Joints with and without Medial Coronoid Process Disease.

OBJECTIVE: This study aimed to evaluate the correlation of static axial radioulnar incongruence (sRUI) measured under general anaesthesia with the real in vivo dynamic RUI (dRUI) during walking. STUDY DESIGN: This was a prospective clinical study that included 6 sound elbows (5 dogs) and 7 medial coronoid process disease (MCPD) affected elbows (6 dogs). MATERIALS AND METHODS: Static axial radioulnar incongruence was measured using the sphere fitting technique on computed tomography-based three-dimensional (3D) models of radius and ulna. The in vivo pose of radius and ulna was derived from radiostereometric analysis during the walk and transferred onto previously calculated 3D models. Dynamic RUI was measured on those adjusted models using the sphere fitting technique, providing a measurement of RUI over time during walk. RESULTS: Mean sRUI was 0.2 mm (standard deviation [SD]: 0.30) in control and 1.4 mm (SD: 0.73) in elbow joints with MCPD; being significantly different (p = 0.0035; confidence interval [CI]: 0.4772-1.8824). Mean dRUI in controls (-0.4 mm; SD: 0.47) was significantly different (p = 0.0004; CI: 0.9918-2.5225) from dRUI in the affected elbows (1.4 mm; SD: 0.73). Comparison of sRUI and dRUI within each group showed difference in the control group (0.2 vs. -0.4 mm; p = 0.0138; CI: 0.1820-1.0014). In affected elbows, no difference between sRUI and dRUI was found (1.4 vs. 1.4 mm; p = 0.8963). CONCLUSION: In normal elbow joints, sRUI does not represent the in vivo condition during weight bearing. Dynamic and slightly negative RUI occurs during loading (0.2 mm positive to -0.4 mm negative RUI). In MCPD affected elbows with sRUI, no dynamic change of RUI occurs during the walk.

Biplanar High-Speed Fluoroscopy of Pony Superficial Digital Flexor Tendon (SDFT)-An In Vivo Pilot Study.

The superficial digital flexor tendon (SDFT) is the most frequently injured structure of the musculoskeletal system in sport horses and a common cause for early retirement. This project's aim was to visualize and measure the strain of the sound, injured, and healing SDFTs in a pony during walk and trot. For this purpose, biplanar high-speed fluoroscopic kinematography (FluoKin), as a high precision X-ray movement analysis tool, was used for the first time in vivo with equine tendons. The strain in the metacarpal region of the sound SDFT was 2.86% during walk and 6.78% during trot. When injured, the strain increased to 3.38% during walk and decreased to 5.96% during trot. The baseline strain in the mid-metacarpal region was 3.13% during walk and 6.06% during trot and, when injured, decreased to 2.98% and increased to 7.61%, respectively. Following tendon injury, the mid-metacarpal region contributed less to the overall strain during walk but showed increased contribution during trot. Using this marker-based FluoKin technique, direct, high-precision, and long-term strain measurements in the same individual are possible. We conclude that FluoKin is a powerful tool for gaining deeper insight into equine tendon biomechanics.