Bilateral non-traumatic elbow luxation in a Yorkshire terrier puppy.

A 10-week-old Yorkshire terrier had lameness of the right forelimb with complete lateral radioulnar luxation at the humerus, consistent with Type III congenital elbow luxation; this is rarely treated in the presence of multiple skeletal deformities. Lateral subluxation of the radial head at the left elbow was diagnosed as Type I congenital elbow luxation. Procurvatum, distal valgus, and external torsion were present in both antebrachiae. Surgical stabilization of the right elbow was performed with temporary transarticular pins in the humeroulnar and radioulnar joints. A custom-made orthosis was applied to support the surgical reduction for 20 wk. Recurrent luxation was not observed. After complete right-sided function was established, the left forelimb showed noticeable instability in the antebrachium, and the puppy frequently fell while running. The lateral collateral ligament of the left elbow was augmented using screws and synthetic ligaments 22 wk after the right-side surgery. Congruity of the left elbow joint improved, and the puppy could bear full weight on the left forelimb, although slight deficits in movement and falling were observed. We demonstrate the effectiveness of combining a temporary transarticular pin and custom-made orthosis while treating Type III congenital elbow luxation and the inadequacy of collateral ligament augmentation alone for treating Type I congenital elbow luxation with antebrachium deformities. Key clinical message: Herein, we observed that a combination of a temporary transarticular pin and a custom-made orthosis was effective for the treatment of Type III congenital elbow luxations.

Luxation bilatérale non traumatique du coude chez un chiot Yorkshire terrier. Un Yorkshire terrier de 10 semaines présentait une boiterie du membre antérieur droit avec une luxation radio-ulnaire latérale complète au niveau de l'humérus, compatible avec une luxation congénitale du coude de type III; ceci est rarement traité en présence de multiples déformations squelettiques. La subluxation latérale de la tête radiale au niveau du coude gauche a été diagnostiquée comme une luxation congénitale du coude de type I. Procurvatum, valgus distal et torsion externe étaient présents dans les deux sections antébrachiales. La stabilisation chirurgicale du coude droit a été réalisée avec des broches trans-articulaires temporaires dans les articulations huméro-ulnaire et radio-ulnaire. Une orthèse sur mesure a été appliquée pour soutenir la réduction chirurgicale pendant 20 semaines. Aucune luxation récurrente n'a été observée. Une fois la fonction complète du côté droit établie, le membre antérieur gauche a montré une instabilité notable de la section antébrachiale et le chiot tombait fréquemment en courant. Le ligament collatéral latéral du coude gauche a été augmenté à l'aide de vis et de ligaments synthétiques 22 semaines après la chirurgie du côté droit. La congruence de l'articulation du coude gauche s'est améliorée et le chiot pouvait supporter tout son poids sur le membre antérieur gauche, bien que de légers déficits de mouvement et des chutes aient été observés. Nous démontrons l'efficacité de la combinaison d'une broche trans-articulaire temporaire et d'une orthèse sur mesure dans le traitement de la luxation congénitale du coude de type III et l'insuffisance de l'augmentation du ligament collatéral seule pour traiter la luxation congénitale du coude de type I avec des déformations de la section antébrachiale.Message clinique clé:Ici, nous avons observé qu'une combinaison d'une broche trans-articulaire temporaire et d'une orthèse sur mesure était efficace pour le traitement des luxations congénitales du coude de type III.(Traduit par Dr Serge Messier).

Postoperative outcomes of combined surgery comprising dorsal laminectomy, transarticular screws, pedicle screws and polymethylmethacrylate for dorsal fixation in 21 dogs with degenerative lumbosacral stenosis.

OBJECTIVE: To retrospectively review the efficacy of combined surgery comprising dorsal laminectomy and dorsal fixation using screws and polymethylmethacrylate as treatment for dogs with degenerative lumbosacral stenosis (DLSS). ANIMALS: 21 client owned dogs diagnosed with DLSS and treated surgically. PROCEDURES: Based on clinical records, signalments, clinical signs, findings from orthopedic and neurological examinations, imaging findings, and postoperative complications were evaluated at the following time points: preoperatively, postoperatively, and 3, 6, 12, 24, and 36 months after surgery. RESULTS: In all 21 cases, clinical signs were alleviated, proprioceptive deficits were improved from 3 months after surgery, and no recurrence of clinical signs was observed during the observation period. Minor complications were observed in 6 cases (28.6%), including implant failure in 2 (9.5%), delayed healing of surgical wounds in 2 (9.5%), seroma in 1 (4.8%), and swelling of the affected area in 1 (4.8%). There was no case with major complications. CLINICAL RELEVANCE: Combined surgery comprising dorsal laminectomy and dorsal fixation using screws and polymethylmethacrylate is a useful treatment that can improve long-term clinical signs in dogs with DLSS.

Force plate analysis of ground reaction forces in relation to gait velocity of healthy Beagles.

OBJECTIVE: To evaluate changes in ground reaction forces (GRFs) in relation to gait velocity using 2 force plates (FPs) for healthy Beagles. ANIMALS: 18 healthy Beagles were included (body weight, 10.45 ± 1.28 kg; age, 26 ± 11 months). PROCEDURES: Ten GRF parameters were measured at three gait velocities (walk, 0.9 to 1.2 m/s; trot 1, 1.6 to 2.0 m/s; and trot 2, 2.1 to 2.5 m/s): peak lateral force (PLF), peak medial force (PMF), lateral impulse (LI), medial impulse (MI), peak propulsive force (PPF), peak braking force (PBF), propulsive impulse (PI), braking impulse (BI), peak vertical force (PVF), and vertical impulse (VI). RESULTS: As velocity increased, the PVF of all limbs increased, the VI of all limbs decreased, and the PPF of the forelimbs increased. At all velocities, PBF and BI were significantly higher than the PPF and PI in forelimbs; however, PBF and BI were significantly lower than the PPF and PI in hindlimbs. There were no significant differences in the PLF, PMF, LI, and MI of the forelimbs and hindlimbs among all velocities. The PLF was significantly higher than the PMF of forelimbs during trot 1 and trot 2. CLINICAL RELEVANCE: These results may be useful when comparing healthy Beagles with diseased ones when premorbid data are not available. Because the forelimbs are mainly responsible for the braking force, it is suggested that weight bearing is more stable in the forelimbs than in the hindlimbs, which are mainly responsible for the propulsive force, and that a greater force is generated laterally than medially during trot.

Prophylactic Efficacy of Tibial Plateau Levelling Osteotomy for a Canine Model with Experimentally Induced Degeneration of the Cranial Cruciate Ligament.

OBJECTIVE: The aim of this study was to clarify the histological effects of tibial plateau levelling osteotomy on cranial cruciate ligament degeneration induced by excessive tibial plateau angle. STUDY DESIGN: Five female Beagles were used to bilaterally create excessive tibial plateau angle models surgically. A second tibial plateau levelling osteotomy was performed 11 months after the first surgery on the right stifle (tibial plateau levelling osteotomy group), and a sham operation that did not change the tibial plateau angle was performed on the left stifle (excessive tibial plateau angle group). At 6 months after the second surgery, the dogs were euthanatized. The cranial cruciate ligament was stained with haematoxylin-eosin to assess the cell density, Alcian-Blue to assess proteoglycans and Elastica-Eosin to assess elastic fibres, and immunohistochemically stained to assess type I (COL1) and type II collagen and SRY-type HMG box 9 (SOX9) expression. RESULTS: In each group, the cranial cruciate ligament degeneration, especially on the tibial side, including the presence of Alcian-Blue- and Elastica-Eosin-positive regions, decreased in COL1-positive regions, and enhancement of SOX9 expression was observed. Besides, compared with the tibial plateau levelling osteotomy group, the excessive tibial plateau angle group showed increases in Alcian-Blue- and Elastica-Eosin-positive regions and a decrease in the COL1-positive regions. CONCLUSION: The results suggested that excessive tibial plateau angle-induced cranial cruciate ligament degeneration can be suppressed by reducing the biomechanical load on the cranial cruciate ligament by performing tibial plateau levelling osteotomy.

Investigation of the effects of excessive tibial plateau angle and changes in load on ligament tensile forces in the stifle joints of dogs.

OBJECTIVE: To investigate the effect of an excessive tibial plateau angle (TPA) and change in compressive load on tensile forces experienced by the cranial cruciate, medial collateral, and lateral collateral ligaments (CCL, MCL, and LCL, respectively) of canine stifle joints. SAMPLE: 16 cadaveric stifle joints from 16 orthopedically normal Beagles. PROCEDURES: Stifle joints were categorized into unchanged (mean TPA, 30.4°) and excessive (mean TPA before and after modification, 31.2° and 41.1°, respectively) TPA groups. The excessive TPA group underwent a TPA-increasing procedure (curvilinear osteotomy of the proximal aspect of the tibia) to achieve the desired TPA. A robotic system was used to apply a 30- and 60-N compressive load to specimens. The craniomedial band of the CCL, caudolateral band of the CCL, MCL, and LCL were sequentially transected; load application was repeated after each transection. Orthogonal force components were measured in situ. Forces on ligaments were calculated after repeated output force measurements as the contribution of each component was eliminated. RESULTS: Increasing the compressive load increased tensile forces on the craniomedial and caudolateral bands of the CCL, but not on the MCL or LCL, in specimens of both groups. At the 60-N load, tensile force on the craniomedial band, but not other ligaments, was greater for the excessive TPA group than for the unchanged TPA group. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that stress on the CCL may increase when the compressive load increases. The TPA-increasing procedure resulted in increased tensile force on the CCL at a 60-N compressive load without affecting forces on the MCL or LCL.

Long-term outcome and progression of osteoarthritis in uncomplicated cases of cranial cruciate ligament rupture treated by tibial plateau leveling osteotomy in dogs.

The object of this study is to evaluate the long-term outcome of hind limb weight-bearing function and progression of stifle osteoarthritis (OA) after tibial plateau leveling osteotomy (TPLO). Groups were classified by the degree of cranial cruciate ligament (CrCL) damage and presence or absence of medial meniscus damage as macroscopically evaluated during surgery. Weight-bearing function was assessed via the peak vertical force (PVF), and OA progression was assessed via the radiographic OA score (OAS) preoperatively and 1, 3, 6, 12, 18, 24, and 36 months postoperatively. In all stifles, PVF was significantly higher within 6 months postoperatively than preoperatively, and this high ratio was maintained for 36 months. The OAS was significantly higher 24 months postoperatively than preoperatively in stifles with a partial CrCL tear, and significantly increased at each timepoint after 3 months postoperatively in stifles with complete CrCL rupture. The OAS remained consistently lower in stifles with a partial CrCL tear and no treatment of the medial meniscus than in stifles with complete rupture. Thus, after TPLO, the weight-bearing function improved in the early postoperative period and was maintained for as long as 36 months. Although OA progressed over time after TPLO, the progression was more gradual in stifles with partial tears than in those with complete rupture. Canine patients would benefit from earlier surgical intervention through development of technology that enables early detection of ligament degeneration.

Biomechanical Effects of Tibial Plateau Levelling Osteotomy on Joint Instability in Normal Canine Stifles: An In Vitro Study.

OBJECTIVE: The aim of the study was to determine the changes in biomechanical characteristics following tibial plateau levelling osteotomy (TPLO) using simulated manual tests. STUDY DESIGN: Twenty-one stifles from healthy Beagle dogs that had undergone TPLO or had not (control) were first tested in the intact form, and then the cranial cruciate ligament (CrCL) was transected in each to provide four test situations: control-intact, control-CrCL-transected, TPLO-intact and TPLO-CrCL-transected. The stifles were then analysed using a robotic joint biomechanical testing system. The craniocaudal drawer, axial rotation and proximal compression tests were applied. RESULTS: The craniocaudal displacement during the drawer test was not significantly different between the control-intact and TPLO-intact. However, the displacement was significantly greater in the TPLO-CrCL-transected than in the control-intact. In the axial rotation test, the internal-external (IE) rotation was significantly greater in the TPLO-intact than in the control-intact. Similarly, the IE rotation was significantly greater in the TPLO-CrCL-transected than in the control-CrCL-transected. In the proximal compression test, craniocaudal displacement was not significantly different among the control-intact, TPLO-intact and TPLO-CrCL-transected. CONCLUSION: These findings suggest that TPLO influences the tension of the collateral ligaments and might generate laxity of the tibiofemoral joint. Instability after the osteotomy might be associated with the progression of osteoarthritis.

Effects of intervertebral distraction screw fixation of the lumbosacral joint on the adjacent lumbar segments in Beagles.

OBJECTIVE: To investigate the effects of intervertebral distraction screw (IDS) fixation of the lumbosacral joint (LSJ) on the intervertebral foraminal area (IFA) and intervertebral stabilization of the LSJ and adjacent lumbar segments in dogs. ANIMALS: 7 healthy Beagles. PROCEDURES: Dorsal laminectomy was performed at the LSJ in each dog to expose the intervertebral disk. The IDS was then inserted into the L7-S1 disk. Computed tomography was performed before and after laminectomy and after IDS insertion (intact, laminectomy, and IDS conditions, respectively) to measure the intervertebral range of motion (ROM) and intervertebral distance (ID) at L7-S1, L6-7, and L5-6 with the LSJ in a flexed and extended position. The intervertebral foramina stenosis rate was calculated from the intervertebral foramina area in entrance, middle, and exit zones. Results were compared among conditions. RESULTS: The ROM at L7-S1 after IDS insertion was lower than that observed before and after laminectomy; no other differences were identified among conditions. With the LSJ in the flexed position, the ID at L7-S1 was larger after IDS insertion than before and after laminectomy; no other differences in ID were identified. In all evaluated zones, the stenosis rate was lower after IDS insertion than before and after laminectomy. No differences in ROM, ID, and stenosis rate were identified among conditions at L6-7 or L5-6. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that IDS fixation of the LSJ restricted lumbosacral ROM and prevented decreases in lumbosacral ID and IFA in healthy dogs. There were no changes at L6-7 and L5-6.

Combined Surgical, Radiation, and Medical Therapies for Osteochondrodysplasia in a Scottish Fold Cat.

Osteochondrodysplasia affects both homozygous and heterozygous Scottish Fold cats, and various treatments have been attempted to control chronic pain and improve mobility in these animals. However, to date, there is no single effective treatment that can be used to treat all cats with Scottish Fold osteochondrodysplasia (SFOCD). A 4 yr old castrated Scottish Fold cat presented with plantar exostoses in the right hindlimb, the largest of which was caudal to the tarsometatarsal joint and had stretched the overlying skin, causing ulceration and bleeding. There was right hindlimb lameness. The cat was diagnosed with SFOCD, and the skin lesions were treated by excision of the exostoses, removal of the damaged skin, and wound closure. All extremities were treated with radiotherapy and subcutaneous pentosan polysulfate for chronic pain. The cat's gait improved after surgery, and increased activity was noted after radiotherapy. There were no signs of excessive bone proliferation or adverse effects at 80 wk postoperatively. In conclusion, a combination of surgical, radiation, and medical therapies could be an effective treatment strategy for SFOCD with skin ulceration.

Analysis of passive tibio-femoral joint movement of Beagle dogs during flexion in cadaveric hind limbs without muscle.

The aim of this study was to evaluate the normal range of motion of the canine tibiofemoral joint and the movement of the tibia relative to the femur, especially the internal/external rotation under flexion. Right stifle joints were harvested from eight skeletally mature Beagle dogs, which were euthanized for reasons unrelated to this study. All muscle tissue was removed from the limbs prior to testing. Flexion and extension tests were conducted using a robotic manipulator with six degrees-of-freedom. Cranial/caudal and medial/lateral displacement and varus/valgus and internal/external rotation were measured at various degrees of flexion. We observed that the tibia rotated internally at an increasing flexion angle with mean peak internal and external rotations of 20.0 ± 13.8° and 4.5 ± 3.6°, respectively. The tibia also tended to displace cranially at an increasing flexion angle, with a mean peak cranial displacement of 8.9 ± 4.4 mm; there was minimal medial displacement when increasing the flexion angle. Valgus rotation also tended to occur at an increasing flexion angle. During the flexion of the canine stifle joint, approximately 20° of internal tibial rotation occurred around the longitudinal axis, along with a rollback motion involving the cranial displacement of the tibia.

Effect of the Centre of Rotation in Tibial Plateau Levelling Osteotomy on Quadriceps Tensile Force: An Ex Vivo Study in Canine Cadavers.

OBJECTIVE: The aim of this study was to determine the effect of the centre of rotation in tibial plateau levelling osteotomy (TPLO) on the tensile force of the quadriceps. MATERIALS AND METHODS: Tibial plateau levelling osteotomy was performed on the left pelvic limbs from 20 normal adult Beagle cadavers. To replicate the tensile force of the quadriceps, gastrocnemius and stifle flexor muscles, these muscles were replaced with wires. The tensile force of each wire, cranial tibial displacement and internal tibial rotation were measured under the following conditions: intact cranial cruciate ligament, transected cranial cruciate ligament, ideally centred osteotomy TPLO (ICO group) and distally centred osteotomy TPLO (DCO group). The ratios of the tensile forces for the wires divided by the vertical force were used for analyses. RESULTS: The mean intact and post-TPLO tibial plateau angles (TPA) in the ICO group were 30.3° ± 1.9° and 6.1° ± 1.6°, respectively, and those in the DCO group were 29.8° ± 2.4° and 6.8° ± 0.9°, respectively. The mean quadriceps tensile force after TPLO was significantly greater in the DCO group (3.9 ± 0.3) than the ICO group (3.3 ± 0.4) (p = 0.006). Both groups exhibited tibial caudal displacement after TPLO. CLINICAL RELEVANCE: The tensile force of the quadriceps muscles changed in accordance with the centre of the osteotomy in TPLO. The DCO group had increased tensile force, which may cause patellar ligament thickening after TPLO. Setting the postoperative TPA at 6° may cause excessive rotation in patients with a normal tensile force of the stifle flexor muscles.

Degenerative changes of the cranial cruciate ligament harvested from dogs with cranial cruciate ligament rupture.

Degenerative cranial cruciate ligament (CCL) rupture is characterized histologically by degenerating extracellular matrix (ECM) and chondroid metaplasia. Here, we describe the progression of chondroid metaplasia and the changes in the expression of ECM components in canine CCL rupture (CCLR). CCLs from 26 stifle joints with CCLR (CCLR group) and normal CCLs from 12 young beagles (control group) were examined histologically and immunohistochemically for expression of type I (COLI), type II (COLII), type III collagen (COLIII) and Sry-type HMG box 9 (SOX9). Cell density and morphology of CCLs were quantified using hematoxylin-eosin staining. The percentage of round cells was higher in the CCLR group than in controls. COLI-positive areas were seen extensively in the connecting fibers, but weakly represented in the cytoplasm of normal CCLs. In the CCLR group, there were fewer COLI-positive areas, but many COLI-positive cells. The percentages of COLII-, COLIII- and SOX9-positive cells were higher in the CCLR group than in controls. The number of spindle cells with perinuclear halo was high in the CCLR group, and most of these cells were SOX9-positive. Deposition of COLI, the main ECM component of ligaments, decreased with increased COLIII expression in degenerated CCL tissue, which shows that the deposition of the ECM is changed in CCLR. On the contrary, expression of SOX9 increased, which may contribute to the synthesis of cartilage matrix. The expression of COLII and SOX9 in ligamentocytes showed that these cells tend to differentiate into chondrocytes.