Objective:The objective of this study is to report radiographic outcomes and complications following repair of proximal tibial apophyseal-epiphyseal fractures with an apophyseal pin and tension-band wire (APTBW). Study Design:Medical records and radiographs of dogs treated with APTBW alone were retrospectively reviewed. Tibial plateau angle (TPA) and mechanical medial proximal tibial angle (mMPTA) were compared in the fractured limbs at preoperative, postoperative, and follow-up time points and to the contralateral limb, using repeated-measures analysis of variance. Bonferroni-adjusted paired comparisons followed significant omnibus tests. Results:Thirty-six fractures in 35 dogs were included (median age: 4.4 months). Union was achieved in 34 of 36 (94.4%) fractures, at a median of 4.1 weeks. Mean TPA of fractured limbs was 12.8 degrees higher than contralateral limbs preoperatively (p < 0.001), but no statistically significant difference was detected at union (p = 0.735). Mean mMPTA did not differ significantly across measurement conditions. Three major and four minor complications occurred, including two construct failures before union. Construct failures resulted from Kirschner wire migration (n = 1) and apophyseal shearing (n = 1). Conclusion:Repairing proximal tibial apophyseal-epiphyseal fractures with APTBW as a sole fixation method resulted in a high rate of union and restoration of normal mean TPA and mMPTA. Routine fixation of the epiphysis may not be necessary in this fracture type.
Objective:The aim of this retrospective cohort study was to compare implant removal rate after tibial plateau leveling osteotomy (TPLO) was performed by a single surgeon on a mobile service versus in an orthopaedic exclusive surgical centre ("in-centre"). Study Design:Records for 916 TPLO performed either on a mobile basis or in-centre were reviewed including whether the implants were subsequently removed. Marginal logistic regression model was used to compare implant removal rates between the two cohorts and based upon type of skin closure (skin sutures vs. intradermal closure). Results:On univariate analysis dogs having TPLO on a mobile basis had significantly higher odds (odds ratio [OR]: 6.5; 95% confidence interval [CI]: 2.1-19.6; p = 0.001) of having their implants removed (4.4%, 15/341) compared with dogs having TPLO in-centre (0.7%, 4/575). Dogs with intradermal skin closure had significantly higher odds (OR: 6.3; 95% CI: 1.5-26.8, p = 0.010) of having their implants removed (3.3%, 17/518) compared with dogs having skin sutures (0.5%, 2/398). However, on multivariable analysis, only location (OR: 27.3; 95% CI: 1.7-449.1; p = 0.021) and not suture (OR: 6.1; 95% CI: 0.6-61.0; p = 0.130) had a significant effect on implant removal rate. Conclusion:There was a significantly higher risk of implant removal when TPLO was performed on a mobile basis in comparison to TPLO performed in an orthopaedic exclusive surgical centre.
Objective:Proximal suspensory ligament (PSL) injuries are a common cause of lameness in horses. Localization of pain in the proximal metacarpal and carpal region remains challenging. Current diagnostic analgesic techniques are not PSL-specific. The aim of this study was to investigate the nerve supply of the PSL, with particular focus on the deep branch of the lateral palmar nerve (DBLPaN), and to develop a landmark-based, ultrasound-guided injection technique targeting this nerve. Study Design:Eighteen limbs from euthanized horses were dissected to describe the anatomy of the DBLPaN and branches, measuring distances from the distal margin of the accessory carpal bone (ACB) to the nerve origin and its insertion on the suspensory ligament. These findings guided development of an ultrasound-guided injection technique, which was assessed in 20 additional limbs. Results:Considerable anatomical variability was observed, with two to six accessory branches per DBLPaN. Mean distance from the distal ACB margin to the DBLPaN origin was 2.5 cm and to the insertion on the PSL was 5.1 cm. Injections were successful in 65%, partially successful in 25%, and unsuccessful in 10% of limbs. Conclusion:The current study provided new detailed information regarding the anatomy of the DBLPaN and of the PSL innervation. The DBLPaN was injected with an accuracy that would be of clinical value. These findings provide a foundation for the development of more specific diagnostic analgesic techniques and warrant further in vivo investigation.
Objective:The objective of this study is to describe the technique, complications, and outcomes of standing needle arthroscopy of the distal interphalangeal joint (DIPJ) in horses. Study Design:This is a retrospective study. Animals:Five cadaver forelimbs; 36 client-owned horses. Methods:A 1.9-mm needle arthroscope was used to evaluate the DIPJ in cadaver limbs and clinical cases. Horses underwent diagnostic and/or therapeutic arthroscopy under standing sedation and local anaesthesia. Data collected included signalment, diagnostic imaging findings, intraoperative findings, complications, and outcomes to 12 weeks postoperatively. Results:Arthroscopy was successfully performed in all cadaver limbs, with consistent visualization of the anatomical features in dorsal and palmar recesses. In clinical cases (12 fragment removals, 24 diagnostic procedures), cartilage defects and capsular tears were frequently identified. Osteochondral fragments were removed successfully in all cases. Complications were minor, consisting of intra-articular bleeding (15 mild, 4 moderate). No infections or major adverse effects occurred. All horses were discharged uneventfully, with no complications reported at 12 weeks. Conclusion:Standing needle arthroscopy of the DIPJ is a safe, minimally invasive technique providing diagnostic and therapeutic benefits while avoiding risks of general anaesthesia.
Objective:The objective of this study is to evaluate racing performance of Thoroughbred yearlings following arthroscopic surgery for osteochondrosis (OC) of the femoropatellar (FP) and tarsocrural (TC) joints. Study Design:This is a retrospective study of Thoroughbreds < 2 years old undergoing arthroscopic surgery for OC in the FP or TC joint (2010-2022). For each case, two age- and sex-matched controls from the same stud farm were selected. Lesions were graded on preoperative radiographs and described. Racing outcomes (number of starts, wins, places, podiums, prize money at 2nd, 3rd, and ≥4-year-old seasons, and career duration) were compared between groups using parametric or nonparametric tests according to data distribution (Student's t-test/analysis of variance or Mann-Whitney U/Kruskal-Wallis tests). Results:A total of 49 horses included: 27 in the FP group and 22 in the TC group. In the FP group, the lateral trochlear ridge was most often affected; 14 were bilateral, two had OC lesions in another joint. In the TC group, the distal intermediate ridge of the tibia was mainly affected; five were bilateral and one had OC lesion in another joint. No significant differences were found between cases and controls in number of starts, wins, places, podiums, and prize money earned at 2nd, 3rd, and ≥4-year-old racing careers or career duration for either group (p > 0.05). In both groups, no significant performance differences were found between unilateral and bilateral cases (p > 0.05). Conclusion:Racing performance after FP or TC OC surgery was comparable to that of unaffected controls. Bilateral cases performed as successfully as unilateral.
Objective:This study aims to quantify implant-induced bone loss and changes in torsional mechanical properties following insertion of three common orthopaedic implants - cortical screws, locking screws and Kirschner wires in rabbit femora. Study Design:Eighteen femora from skeletally mature New Zealand White rabbits were used. Femora were randomly assigned to receive a bicortical defect created using a self-tapping cortical screw, self-tapping locking screw or smooth Kirschner wire (n = 6 per group). Following implant insertion and removal, specimens underwent micro-computed tomography to quantify normalized peri-implant bone volume loss, followed by torsional mechanical testing to failure. Results:Qualitative assessment revealed larger bone chips at the insertion site for both screw types compared with Kirschner wires. Micro-computed tomography analysis demonstrated significantly greater total bone volume loss following cortical screw insertion (11.7 ± 3.4%) compared with locking screws (8.6 ± 1.4%; p = 0.0459). No differences were observed between groups in torsional rigidity, yield torque, ultimate rotation and ultimate torque during biomechanical testing. Conclusion:These findings indicate that, although self-tapping cortical screws induce greater volumetric bone loss than locking screws in rabbit femora, this damage does not translate into significant differences in torsional rigidity, yield torque, ultimate rotation or ultimate torque among the tested implants. Implant insertion alone is therefore unlikely to be the primary contributor to catastrophic failure seen with specific fracture repair techniques in the rabbit.
Objective:The aim of this study was to describe and assess a technique for the measurement of cementless (BioMedtrix Biologic Fixation [BFX]) total hip replacement implant orientation using computed tomography (CT). Study Design:Postoperative CT studies of 15 dogs that had total hip replacement with a 24 mm BFX cup and BFX stem were reviewed retrospectively. Multiplanar reconstructed CT images were manipulated to generate standard positions of the pelvis and femur. Open face version, angle of lateral opening (ALO), inclination of the cup and stem anteversion were measured sequentially. Cases were anonymized, randomized and measured three times by two observers. Results:Intraclass correlation coefficients for cup open face version, cup ALO, cup inclination and stem version were 1.0 and 1.0, 0.98 and 0.98, 0.99 and 0.99, and 1.0 and 0.97, for observers 1 and 2, respectively. The interclass correlation coefficients indicating interobserver variation for cup open face version, cup ALO, cup inclination and stem version were 1.0, 0.99, 0.99 and 0.99, respectively. Conclusion:The reported technique for measurement of BFX total hip replacement implant orientation is highly repeatable and allows objective measurement of implant orientation, including parameters which are not accessible radiographically.
Objective:This study aimed to describe a population of dogs that had undergone trochlear ridge prosthetic replacement with the RidgeStop surgical procedure for the correction of medial patellar luxation (MPL), and to describe clinical outcomes, owner satisfaction and radiographic changes. Study Design:Retrospective, observational review of 20 client-owned dogs. Data, including MPL and lameness grades, implant use, complications and concurrent surgical procedures, were recorded. Radiographic review was performed. A client survey gathered data on clinical signs, perceived disability and recovery time. Results:Medial patellar luxation was eliminated clinically in 24/25 limbs and radiographically in 24/25 limbs. No intraoperative complications occurred, and there was no evidence of implant movement, failure or infection. One dog with clinical and radiographic evidence of grade 4/4 MPL preoperatively subsequently experienced recurrent luxation. Owners perceived postoperative improvement in 10/14, worsening in 2/14 and no change in 2/14. Stifle effusion and osteoarthritis, particularly at the trochlear ridges and patella, were common in preoperative radiographs. Proximal patellar ligament thickening and stifle effusion were common in follow-up radiographs. Conclusion:The RidgeStop implant prevented MPL in most patients with a low complication rate. Recurrent luxation was an uncommon complication and may be associated with a higher preoperative grade. Proximal patellar ligament thickening and stifle effusion were common short-to-medium term radiographic findings.
Objective:The objective of this study is to compare the axial compression behaviour of locking plate constructs applied with different fixation functions in the canine femur, focusing on construct stiffness, resistance to plastic deformation, and bone-implant load sharing. Methods:Femora were allocated to four groups: intact (control), compression, neutralization, or bridge fixation using a locking plate. Compression and neutralization constructs restored the bone column, whereas bridge fixation eliminated load sharing by spanning a diaphyseal defect. All specimens underwent axial compression testing until failure, with stiffness, apparent elastic limit, maximum load to failure, and failure modes recorded. Results:Construct stiffness varied according to fixation function. Intact femora and compression constructs demonstrated the highest stiffness values and were not significantly different from each other. Bridge constructs showed significantly lower stiffness values than intact, compression, and neutralization constructs. Intact femora also demonstrated higher apparent elastic limit and maximum load values than neutralization and bridge constructs. Plate bending was the predominant failure mode, especially in bridge fixation. Conclusion:Fixation function strongly influences the mechanical behaviour of locking plate constructs. Restoration of the bone column promotes load sharing and is associated with increased construct stiffness under axial compression. Bridge fixation places greater mechanical demand on the implant, increasing susceptibility to plastic deformation.
Objective:The aim of this study was to determine the utility of routine follow-up radiographs after cranial closing wedge ostectomy (CCWO) for cranial cruciate ligament disease in dogs with a normal clinical examination and no owner concerns. Study Design:Records were retrospectively reviewed to identify dogs that underwent CCWO with no complications reported prior to routine follow-up re-examination. Owner-reported concerns, clinical examination abnormalities and radiographic abnormalities were identified, and any resulting alteration to the ongoing rehabilitation plan was recorded. Radiographs were subsequently blindly assessed by a European College of Veterinary Surgeons board-certified specialist and a European College of Veterinary Surgeons surgical resident. Radiographic abnormalities and resultant changes to the rehabilitation plan were evaluated. Results:One hundred and thirty-four CCWO surgeries were evaluated. Dogs presented for follow-up at a median of 8 weeks (range 6-12) postoperatively. No owner concerns or clinical examination abnormalities were identified in 120/134 (90%). Of these, 33/120 (28%) had altered treatment recommendations based solely on radiographic findings by at least one of the clinicians. Conclusion:Radiographic findings at routine follow-up altered rehabilitation regimes in 14 to 28% of dogs after CCWO, even when there were no concerns from the owners or on examination. We, therefore, recommend performing radiographs as routine at follow-up after CCWO even when the recovery appears uneventful.
Objectives:The aims of this study were to describe a cranial arthroscopic portal to the supratrochlear foramen and to assess the feasibility and accuracy of retrograde transarticular drilling of the anconeal process in canine cadaveric elbows. Study Design:Cadaver elbows (n = 8) were instrumented through a cranial portal in the distal humerus using a NanoScope. The scope was manoeuvred through the supratrochlear foramen to inspect the anconeal process. A 2.0-mm tunnel simulating the pilot hole for an ununited anconeal process repair was performed using a C guide, cannulated drill bits and NanoScope guidance. Experimental measures included arthroscopic anconeal process identification, surgical time, computed tomography and gross dissection to assess for critical structure damage and drill tunnel aperture location and trajectory. The first two elbows were used for technique development; the remaining six elbows have reported outcome measures. Results:Mean surgery time was 16.6 (standard deviation 3.0) minutes. All six tunnels drilled had acceptable trajectories based on computed tomography and gross dissection. Major damage to critical structures was not observed in any specimen; however, tunnels were directly adjacent to transcubital vessels and a musculocutaneous nerve branch. Conclusion:This technique was feasible, provided visualization of the anconeal process, and allowed accurate drilling of the anconeal process in a cadaveric model. Clinical feasibility and safety require validation in a clinical study.
Objective:The aim of this study was to assess whether Dejour's lateral radiographic signs of femoral trochlear dysplasia are identifiable in healthy and patellar luxation (PL)-affected dogs; and whether computed tomography (CT) lateral reconstructions can substitute for radiography. Study Design:Forty femoral trochleae were divided into controls without PL (n = 15) and dogs with PL (n = 25). Mediolateral stifle radiographs and CT-based lateral reconstructions were randomized and read by a blinded observer for Dejour signs (crossing, supratrochlear spur, double contour). Agreement between modalities was evaluated with Cohen's kappa and McNemar's test (p < 0.05). Results:Dejour signs were absent from controls on both modalities except for one CT trochlea. In controls, method agreement for femoral trochlear dysplasia signs (one or more signs) was high (observed agreement 93%). In PL stifles, one or more Dejour signs were present in 68% on radiographs and 72% on CT. On radiographs: crossing 48%, supratrochlear spur 40%, double contour 28%; and on CT: 48%, 44%, 28%, respectively. Sign combinations occurred in 36%. Agreement between radiography and CT in PL stifles was substantial (observed agreement 95-100%; κ 0.89-1.00). An ancillary finding - a single projection line consistent with a convex trochlea ('dome' sign) - was observed in 24% of PL trochleae both with radiography and CT, mostly grade-4 PL. Conclusion:Dejour femoral trochlear dysplasia signs are identifiable in dogs with PL and rare in normal dogs. Computed tomography lateral reconstructions reliably depict these features and may substitute for radiography. Recognition of Dejour sign and the proposed dome sign may aid preoperative planning and surgical decision-making in canine PL.
Objective:This study evaluated the therapeutic effects of intra-articular stanozolol on the cartilage of the femorotibiopatellar joint in rabbits with induced and early-stage osteoarthritis (OA). Study Design:A total of 12 rabbits were allocated to two groups-treatment (stanozolol) and control (saline)-and subjected to OA induction via transection of the cranial cruciate ligament of the femorotibiopatellar joint. After 4 weeks of intra-articular treatment, the animals were euthanized and the articular cartilage was assessed anatomopathologically. Results:No differences were observed between the treatment and control groups (p > 0.05), indicating that stanozolol did not affect the progression of cartilage damage in early stage of osteoarthritis. The medial femoral condyle was the site of the most severe cartilage damage within the femorotibiopatellar joint. Femoral cartilage exhibited greater macroscopic damage than tibial cartilage. Conclusion:It was concluded that intra-articular stanozolol administration in rabbits with induced OA does not produce therapeutic effect on femorotibiopatellar joint cartilage in the short term or during the early stage of the disease.
Objective:To describe the short- and intermediate-term outcomes of tibial plateau leveling osteotomy (TPLO) in cats. Study Design:Electronic medical records of cats with cranial cruciate ligament tears treated with TPLO at nine hospitals between January 2015 and November 2024 were reviewed. Cats were included if they had a TPLO procedure and excluded if they had concurrent ipsilateral orthopedic procedures or underwent additional concurrent procedures other than simultaneous contralateral stifle surgery. Physical and radiographic examination metrics, including bone healing scores, were used to assess short-term outcomes (<6 months). Owner responses to Feline Musculoskeletal and Pain Index (FMPI) surveys were used to assess intermediate-term outcomes (<12 months). Results:Thirty-two stifles were operated on in 28 cats. Complications occurred in 9/32 stifles, and they were categorized as eight minor and one major complications. The median (range) pre- and postoperative lameness grades were 3 (1-5) and 0 (0-2) out of 5, respectively. Cranial tibial thrust was neutralized in 28/32 stifles; the remaining four stifles did not have information about stifle stability. The median 10-point radiographic bone healing score after 8 weeks was 8. The median FMPI score decreased from 16 to 4 with a median reduction of 14 (maximum score: 36). Conclusion:TPLO was associated with neutralization of cranial tibial thrust in cats and may be a viable treatment option.
Objective:To determine whether the elution of antibiotics from calcium sulfate (CaSO4) beads differs following ethylene oxide gas sterilization compared with their nonsterilized counterparts and whether sterilization affects their antibacterial activity after a period of storage for up to 6 months post curation. Study Design:Prospective controlled laboratory study. Sample Population:3 mm diameter CaSO4 beads impregnated with either amikacin, gentamicin, cefazolin, vancomycin, or no antibiotic, each with or without ethylene oxide gas sterilization. Methods:Antibiotic-impregnated CaSO4 beads were created at the beginning of the study. Half of the beads underwent gas sterilization and all beads were stored in the clinic until testing. Beads were tested against a clinical strain of Staphylococcus pseudintermedius via Modified Kirby-Bauer agar diffusion assay testing, measuring the zone of inhibition (ZOI) produced every 24 hours for 5 days. Beads were tested at 1 day, 1 week, 1 month, 3 months, and 6 months post curation with or without gas sterilization, and their changes were compared using mixed-effects linear models. Results:Beads sterilized using ethylene oxide showed similar ZOI over 5 consecutive days of elution compared with the nonsterilized beads. Beads that were sterilized and stored for up to 6 months demonstrated similar ZOI to beads that were not sterilized and tested immediately. Conclusion:Gas sterilization followed by storage for up to 6 months post curation did not impair the in vitro activity of antibiotic-impregnated CaSO4 beads when tested against a clinical strain of S. pseudintermedius. Clinical Significance:Antibiotic impregnated CaSO4 beads can be created in advance, gas sterilized, stored in the clinic and retain antibacterial activity for up to 6 months post curation.
Objective:The aim of this study was to describe the signalment of dogs with radioulnar interosseous ligament disease and their radiographic and clinical features, and to distinguish two entities: radioulnar ischemic necrosis (RUIN) and radioulnar ligament desmopathy (RULD). Study Design:This multicenter retrospective case series included data from dogs from referral centers and the Veterinary Information Network (VIN) database. Cases were included based on compatible clinical signs and radiographic findings. RUIN lesions were characterized by focal cortical lysis of the caudal aspect of the radius and the cranial aspect of the ulna. RULD lesions were characterized by smooth bone proliferation on the lateral aspect of the antebrachial bones. Results:Among the 233 dogs included (9 referral cases, 224 from VIN), 115 had RUIN, and 118 had RULD. RUIN primarily affected small, chondrodystrophic breeds, while RULD was more common in large, nonchondrodystrophic breeds. Elbow dysplasia was a frequent comorbidity in RUIN and RULD cases. In the referral cases, these lesions were thought to be occasionally associated with mild to moderate forelimb lameness, typically responsive to conservative therapy. Conclusion:RUIN and RULD are underrecognized orthopedic entities with differing breed predispositions. The proposed entities aim to support clinicians in improving future identification of those entities and guiding future research for pathogenesis and case management.
To evaluate the effect of a 3.5 mm tibial plateau leveling osteotomy (TPLO) locking compression plate on serial postoperative tibial plateau angle (TPA) maintenance, short-term osteotomy healing, and complication rates in dogs weighing 45 to 70 kg treated for naturally occurring cranial cruciate ligament disease.Retrospective study.The difference between the mean postoperative TPA and the mean 6-week re-evaluation TPA was 1.9 ± 2.27 degrees (p < 0.0001). The patient's weight and limb laterality were found to have a significant effect on the TPA difference, which increased by 0.144 degrees for each kg increase in body weight and by 2.114 degrees for a left hindlimb compared with a right hindlimb. The median healing score was 3/5, with a range of 2 to 5. Eight out of 36 dogs experienced postoperative complications, with 2/36 dogs developing surgical site infections.The use of a 3.5 mm TPLO locking compression plate in dogs weighing 45 to 70 kg revealed a significant change in TPA difference and poor bone healing. Complication rates were similar to those of previous studies.
Objectives:The aim of this study was to describe the computed tomography features of proximal gastrocnemius musculotendinopathy in dogs, and to compare clinical presentation, associated lesions and outcomes with the existing literature. Methods:This retrospective study included 24 dogs diagnosed with proximal gastrocnemius musculotendinopathy based on contrast-enhanced computed tomography between January 2019 and April 2025. Signalment, clinical presentation, concurrent musculoskeletal or neurological disorders, imaging findings, treatment protocols and clinical outcomes were analysed. Results were compared to published magnetic resonance imaging- and radiograph-based series. Results:Dogs were predominantly active working breeds, with Border Collies representing 33% of cases. Chronic hindlimb lameness was the principal clinical sign. Computed tomography revealed soft tissue swelling and contrast enhancement at the origin of the lateral gastrocnemius head in all cases. Proximal gastrocnemius musculotendinopathy was isolated in 42% of cases, while others had concurrent cranial cruciate ligament rupture or lumbosacral stenosis. Conservative treatment, including analgesia and physiotherapy, led to favourable outcomes in 14 of 17 followed dogs. Clinical Significance:Proximal gastrocnemius musculotendinopathy is a cause of chronic lameness in athletic dogs. Computed tomography imaging, despite limitations compared to magnetic resonance imaging, provides useful diagnostic information. Early recognition of proximal gastrocnemius musculotendinopathy using computed tomography may prevent unnecessary surgical exploration of the stifle in dogs erroneously suspected of cranial cruciate ligament rupture.
To determine the correlation between preoperative and intraoperative tibial plateau leveling osteotomy (TPLO) planning landmarks and measurements.In canine cadaveric stifles (n = 39), the medial collateral ligament (MCL), palpable tibial tuberosity (pTT), patellar ligament enthesis (PLE), and the medial anatomic groove caudal to the attachment of the (patellar) ligament (MAGCAL) were labeled and radiographed. The location of the pTT and PLE were compared with the radiographic location of the tibial tuberosity (rTT); the MCL location was compared with the radiographic location of the intercondylar eminence (ICE), and the planned osteotomy location was compared with the MAGCAL position.There was no statistically significant difference between the location of the rTT to the pTT and PLE. The MCL was directly centered over the ICE in only 20/39 stifles, with the rest being caudal. The planned osteotomy was cranial to or within the MAGCAL in 27/32 pelvic limbs.The MCL should be used cautiously for osteotomy planning, and the MAGCAL may be a useful anatomic landmark for intraoperative TPLO planning.
