- Houston, Texas
- Veterinary Medicine, Education, Biomechanics, Gait Biomechanics, Sport Biomechanics, Knee Biomechanics, and 18 moreMusculoskeletal Biomechanics, Hip Biomechanics, Orthopedics, Joint Replacement, Arthroscopy, Hip Arthroscopy, Arthroscopy Devices, Arthroscopy of the Hip and Shoulder, Knee Arthroplasty, Knee, Knee Osteoarthritis, Cartilage of Knee, Unicompartmental Knee, ACL reconstruction, ACL Biomechanics, Bone graft, Anterior Cruciate Ligament, Tendon and Ligament injuries, Biomechanical Properties of Ligaments, and Tendon and Ligament Engineeringedit
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SummaryObjective To evaluate the outcome of surgical site infection (SSI) associated with tibial plateau levelling osteotomy (TPLO) implants following treatment by medical management alone or implant removal with or without the... more
SummaryObjective To evaluate the outcome of surgical site infection (SSI) associated with tibial plateau levelling osteotomy (TPLO) implants following treatment by medical management alone or implant removal with or without the administration of antibiotic medication.Animals Ninety dogs (104 TPLO surgical procedures).Methods Records of dogs that had undergone TPLO implant removal due to SSI were reviewed. Outcome following treatment with antibiotic medications without implant removal, and treatment with implant removal with and without the administration of antibiotic medications was evaluated.Results Treatment of SSI with antibiotic medication alone failed in 88.9% (64/72) of the dogs. The clinical signs of SSI resolved in 94.9% (74/78) of the dogs treated with implant removal (with and without the administration of antibiotic medication postimplant removal). The effect of administration of antibiotic medication on outcome of treatment of the SSI by implant removal was not significant. The rate of SSI associated with the Synthes implant was higher than with the Slocum implant, but not the New Generation implant.Conclusion Implant removal with or without the administration of antibiotic medication post-implant removal for treatment of TPLO SSI provided superior outcome compared to treatment with antibiotic medications without implant removal.Clinical significance Implant removal should be considered for TPLO SSI that have not responded to appropriate medical management. Further investigation of the various TPLO implants and their effects on postoperative infection rate is warranted.
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Bilateral cranio-dorsal coxo-femoral luxations were created in 20 canine cadavers. After reduction, ischio-ilial pins were placed bilaterally, at one of three insertion sites ventral or ventro-lateral to the ischiatic tuberosity.... more
Bilateral cranio-dorsal coxo-femoral luxations were created in 20 canine cadavers. After reduction, ischio-ilial pins were placed bilaterally, at one of three insertion sites ventral or ventro-lateral to the ischiatic tuberosity. Stability of the reduction was assessed before and after pin placement. All (20) pins placed in the central position prevented the femoral head from luxating to the cranio-dorsal position, while cranio-dorsal luxations occurred in two of 10 cadavers after medial pin placement and two of 10 cadavers after lateral pin placement. The pelvic region was dissected to assess the relationship of the pin to the regional anatomy. Pins placed at the central position were often in contact with the ischiatic nerve, while pins placed in the medial and lateral positions were not. Pins placed in the central position afford the greatest stability; however, they also have the greatest potential of ischiatic nerve trauma.The stability, resulting from ischio-ilial pinning, to prevent coxo-femoral luxation was studied in canine cadavers
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Research Interests: Medicine and Pneumothorax
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Introduction Arthroscopy can be a useful tool when treating dogs for cranial cruciate ligament rupture. Arthroscopic-assisted debridement of the torn ligament and treatment of meniscal tears prevents the need for arthrotomy and incision... more
Introduction Arthroscopy can be a useful tool when treating dogs for cranial cruciate ligament rupture. Arthroscopic-assisted debridement of the torn ligament and treatment of meniscal tears prevents the need for arthrotomy and incision of other periarticular soft tissues. Meniscal release can also be performed under arthroscopic guidance. Lower morbidity and enhanced visualization is achieved with arthroscopy. Second-look arthroscopic evaluation of patients undergoing previous stabilization for cruciate tears is indicated for treatment of meniscal tears, meniscal release, and evaluation of the cranial cruciate ligament, caudal cruciate ligament, previous meniscal procedures, osteoarthritis and synovitis. Patterns of articular wear can be assessed in patients having an unsatisfactory outcome following TPLO. Second-look arthroscopy is particularly valuable for low morbidity follow-up evaluations of the joint in experimental studies.
SummaryThe effects of a single intramuscular administration of polysulfated glycosaminoglycan (PSGAG, Adequan®a) on activated partial thromboplastin time (APTT), prothrombin time (PT), complete blood count (CBC), biochemical profile and... more
SummaryThe effects of a single intramuscular administration of polysulfated glycosaminoglycan (PSGAG, Adequan®a) on activated partial thromboplastin time (APTT), prothrombin time (PT), complete blood count (CBC), biochemical profile and urinalysis were determined in six adult cats. An injection of 5 mg/kg of PSGAG was given to three of the cats, and an injection of 25 mg/kg was given to the other three cats. Following a seven-day crossover interval, the doses were reversed. Serial blood and urine samples were collected over a 48-hour period after each injection. Administration of PSGAG resulted in a transient, dose-dependent increase of APTT and PT. Prolonged bleeding from the venipuncture sites in the 25 mg/kg group was observed. Some of the CBC, biochemical profile, and urinalysis values changed following treatment, but clinically significant adverse reactions were not noticed.Polysulfated glycosaminoglycan (Adequan®) is a heparin analogue with chondroprotective and anticoagulant ...
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SummaryTwenty-one dogs with craniodorsal coxofemoral luxation were managed with placement of an ischio-ilial pin. The overall success rate in maintaining reduction was 73%, with pins placed at a central position resulting in the lowest... more
SummaryTwenty-one dogs with craniodorsal coxofemoral luxation were managed with placement of an ischio-ilial pin. The overall success rate in maintaining reduction was 73%, with pins placed at a central position resulting in the lowest incidence of reluxation (p = 0.095). Postoperative complications included pin migration (n = 2), septic arthritis (n = 1), pressure sores n = 3), and decubital ulcers (n = 1).
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SummaryThe IMEX™ Circular External Skeletal Fixation (CESF) System was used to stabilize fractures (12 radius and ulna and five tibia and fibula) in 15 dogs and two cats and arthrodeses (two pancarpal, one talocrural and one pantarsal) in... more
SummaryThe IMEX™ Circular External Skeletal Fixation (CESF) System was used to stabilize fractures (12 radius and ulna and five tibia and fibula) in 15 dogs and two cats and arthrodeses (two pancarpal, one talocrural and one pantarsal) in four dogs. The ages of the animals with fractures ranged from six months to nine years (mean ± SD: 2.7 ± 2.5 years; median: 2.0 years) and the body weights of dogs with fractures ranged from 5.4 kg to 48.6 kg (mean ± SD: 21.3 ± 12.6 kg; median: 22.7 kg). The ages of the dogs having arthrodeses ranged from eight months to two years (mean ± SD: 18±10 months; median: 18 months) and body weights of dogs with arthrodeses ranged from 19.0 kg to 29.1 kg (mean ± SD: 22.7 ± 4.7 kg; median: 21.4 kg). Ten fractures were open and four had been previously managed with another form of stabilization. Ten fractures were comminuted and all of the fractures involved the diaphysis; two extended to the distal metaphysis. An extensive open reduction was used on three, ...
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SummaryCarprofen (D,L-6-chlor-alphamethylcarbazole-2-acetic acid) is a nonsteroidal anti-inflammatory drug with demonstrated therapeutic activity in the relief of clinical signs of degenerative joint disease in laboratory animal models... more
SummaryCarprofen (D,L-6-chlor-alphamethylcarbazole-2-acetic acid) is a nonsteroidal anti-inflammatory drug with demonstrated therapeutic activity in the relief of clinical signs of degenerative joint disease in laboratory animal models and in human trials. The double-blind clinical study, reported herein, compared the therapeutic efficacy of carprofen with that of a placebo, in the acute relief of clinical canine degenerative joint disease. Twohundred and nine cases were collected from 10 studies in three geographic regions of the USA. The results of logistic analysis showed that dogs treated with carprofen were 24.8 times more likely to receive a positive evaluation by the veterinarian than those treated with a placebo (p <0.01). The odds of showing improvement, when evaluated by the owners, were 13.4 times greater than placebo (p <0.01). The evaluation from the veterinarian and the owner had excellent agreement (Kappa = 0.997) for dogs treated with carprofen and good agreeme...
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SummaryAn ilio-femoral external fixator was applied to a 13-year-old male, castrated mixed breed dog with a caudal ventral luxation that persistently luxated following both closed reduction and open reduction with a total hip replacement.... more
SummaryAn ilio-femoral external fixator was applied to a 13-year-old male, castrated mixed breed dog with a caudal ventral luxation that persistently luxated following both closed reduction and open reduction with a total hip replacement. The external fixator was placed in order to temporarily maintain reduction during soft tissue healing. Upon removal of the external fixator the dog underwent physical therapy. Reduction was maintained and the dog returned to normal function.
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ObjectiveTo assess the accuracy of a proportion‐corrected radiographic cementless femoral stem level calculation in a cadaver model.Study designCadaveric study.Sample populationTwelve cadaveric canine femurs.MethodsCementless femoral... more
ObjectiveTo assess the accuracy of a proportion‐corrected radiographic cementless femoral stem level calculation in a cadaver model.Study designCadaveric study.Sample populationTwelve cadaveric canine femurs.MethodsCementless femoral stems were implanted in 12 cadaver femurs at three stem levels. Craniocaudal projection radiographs of the implanted femurs were obtained at 0°, 10°, 20°, 30°, and 45° angulations in the sagittal plane (relative to the radiographic plate) and at 0°, 15°, and 30° internal and external axial rotation. A proportional calculation including actual stem length, radiographically measured stem length, and radiographically measured stem level relative to the greater trochanter (uncorrected stem level) was solved to yield a corrected stem level. The errors of the stem level measurements were compared.ResultsWith 0° or 15° of internal rotation, the true stem level differed by more than 0.5 mm from corrected stem level in 2 of 30 tested femoral positions. It differed from the uncorrected stem level in 10 of 30 positions. With 15° and 30° external rotation or 30° internal rotation, the corrected stem level was not more accurate than the uncorrected stem level for any femoral position.ConclusionUse of a proportion correction minimized variability in the stem‐level measurements due to sagittal angulation (up to 30°) of the femur at 0° or 15° of internal rotation.Clinical significanceA proportion correction can improve the accuracy of femoral stem‐level assessment on craniocaudal projection radiographs, which may aid in the detection of subsidence after cementless total hip replacement.
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Background An osteotomy procedure option for stabilization of the CrCL deficient stifle is the Center of Rotation of Angulation (CORA) Based Leveling Osteotomy (CBLO). The CBLO procedure involves a proximal tibial plateau leveling... more
Background An osteotomy procedure option for stabilization of the CrCL deficient stifle is the Center of Rotation of Angulation (CORA) Based Leveling Osteotomy (CBLO). The CBLO procedure involves a proximal tibial plateau leveling osteotomy based on the magnitude of the CORA. Correction of the CORA magnitude results in the desired postoperative tibial plateau angle (TPA) without secondary translation. If translation is prevented, the amount of bone contact across the osteotomy is maximized. This coupled with the ability to apply compression across the osteotomy with a cannulated compression screw (CCS) and tension band increases the strength of the construct. The objectives of this descriptive case series is to assess osseous bridging of the osteotomy at 35 days following a CBLO stabilized with a bone plate, CCS, and tension band. A second objective is to determine if there is a shift of the postoperative TPA when compared to TPA at final radiographic evaluation. Results Forty-seven...
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SummaryComplete or partial rupture of the cranial cruciate ligament (CCL) is a common injury of the canine stifle. Most practicing veterinarians would agree that optimal outcome is best achieved with surgical intervention. A popular... more
SummaryComplete or partial rupture of the cranial cruciate ligament (CCL) is a common injury of the canine stifle. Most practicing veterinarians would agree that optimal outcome is best achieved with surgical intervention. A popular method of stabilization is an extra-articular suture stabilization. The objective of this manuscript is to describe suture placement in a more isometric position as compared to traditional suture placement. A second objective is to introduce the veterinary surgeon to novel anchor products used for stabilization.
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ObjectiveTo compare distraction index (DI) with hip arthroscopy findings in juvenile dogs with hip dysplasia undergoing unilateral or bilateral double pelvic osteotomy (DPO).Study designRetrospective case series.AnimalsTwenty dogs (36 hip... more
ObjectiveTo compare distraction index (DI) with hip arthroscopy findings in juvenile dogs with hip dysplasia undergoing unilateral or bilateral double pelvic osteotomy (DPO).Study designRetrospective case series.AnimalsTwenty dogs (36 hip joints).MethodsMedical records from dogs undergoing unilateral or bilateral DPO (2011–2016) were reviewed. Distraction index was measured by using distraction view radiographs. Arthroscopic images were analyzed. Cartilage was graded by using the modified Outerbridge scale (0 = arthroscopically normal, 1 = chondromalacia, 2 = surface fibrillation, 3 = deep fissuring, 4 = full‐thickness cartilage loss, and 5 = eburnation of exposed subchondral bone). Dorsal acetabular rim, acetabular labrum, the ligament of head of the femur, and synovitis were graded by using a four‐point scale (normal, mild, moderate, severe). Spearman and Pearson correlations were used to compare DI between grade groups and age.ResultsDistraction index ranged from 0.4 to 1.0 (mean...
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Objective—To evaluate 2 plate designs for pancarpal arthrodesis and their effects on load transfer to the respective bones as well as to develop a computational model with directed input from the biomechanical testing of the 2 constructs.... more
Objective—To evaluate 2 plate designs for pancarpal arthrodesis and their effects on load transfer to the respective bones as well as to develop a computational model with directed input from the biomechanical testing of the 2 constructs. Sample—Both forelimbs from the cadaver of an adult castrated male Golden Retriever. Procedures—CT imaging was performed on the forelimb pair. Each forelimb was subsequently instrumented with a hybrid dynamic compression plate or a castless pancarpal arthrodesis plate. Biomechanical testing was performed. The forelimbs were statically loaded in the elastic range and then cyclically loaded to failure. Finite element (FE) modeling was used to compare the 2 plate designs with respect to bone and implant stress distribution and magnitude when loaded. Results—Cyclic loading to failure elicited failure patterns similar to those observed clinically. The mean ± SD error between computational and experimental strain was < 15% ± 13% at the maximum loads ap...
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Research Interests: Skeletal muscle biology, Medicine, Dogs, Anatomy, Animals, and 6 moreCadaver, Elbow Joint, Ulna, Veterinary Sciences, elbow, and brachialis
Table S1. Averaged data of radiographic measurements by observers. (PDF 237 kb)
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Research Interests: Orthodontics and Medicine
Osteoarthritis is the most common cause of chronic pain in dogs with approximately one in five adult dogs having OA. OA (sometimes referred to as degenerative joint disease) is a slowly progressive degenerative disease involving the... more
Osteoarthritis is the most common cause of chronic pain in dogs with approximately one in five adult dogs having OA. OA (sometimes referred to as degenerative joint disease) is a slowly progressive degenerative disease involving the entire joint: articular cartilage, subchondral bone, synovial lining, joint fluid, ligaments, and muscles. Osteoarthritis is commonly classified as primary OA or secondary OA. Primary OA is associated with aging and chronic loading and wear of the articular surface. Secondary OA (the most common form seen in dogs) has many acquired and congenital etiologies including: ligamentous injury (CCL), abnormal joint conformation (elbow dysplasia), osteochondrosis (OCD shoulder). In general, OA can develop in any joint where abnormal stresses are imposed on a normal joint or alternatively where normal stresses are imposed on an abnormal joint. Although more senior dogs exhibit clinical signs of OA as compared to their younger counterparts, younger dogs may also e...
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Objectives This study aims to assess and compare the T2 relaxation times for articular cartilage of normal canine stifle joints in four regions by T2 mapping using a 1.5-T magnetic resonance imaging (MRI). Methods In vivo prospective... more
Objectives This study aims to assess and compare the T2 relaxation times for articular cartilage of normal canine stifle joints in four regions by T2 mapping using a 1.5-T magnetic resonance imaging (MRI). Methods In vivo prospective study: 20 hindlimbs (left and right) from 10 normal healthy beagle dogs (n = 20). The region of interest (ROI) was subdivided into medial and lateral condyles of femoral cartilage (MF and LF, respectively) and medial and lateral condyles of tibial cartilage (MT and LT, respectively). The T2 relaxation times were assessed in regions where the cartilage thickness was greater than 0.5 mm. Results The median maximum cartilage thickness (mm) of the four ROI were 0.7 (range: 0.9–0.6), 0.6 (range: 0.7–0.5), 0.7 (range: 0.9–0.5) and 0.6 (range: 0.8–0.5) at MF, LF, MT and LT, respectively. The errors in the measurement (%) of the four ROI were 64.3 (range: 50.0–75.0), 75.0 (range: 64.3–90.0), 64.3 (range: 20.0–90.0) and 75.0 (range: 56.3–90.0) at MF, LF, MT and ...
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To evaluate the short-term clinical performance of an anatomically pre-contoured, locking plate in dogs undergoing tibial plateau leveling osteotomy (TPLO) for cranial cruciate ligament (CrCL) disease. Prospective, multi-center clinical... more
To evaluate the short-term clinical performance of an anatomically pre-contoured, locking plate in dogs undergoing tibial plateau leveling osteotomy (TPLO) for cranial cruciate ligament (CrCL) disease. Prospective, multi-center clinical study. Dogs (n = 56) undergoing TPLO. Signalment and operative data were recorded. Preoperative, postoperative, and follow-up tibial plateau angle (TPA) were measured from radiographic images. Intraoperative and postoperative complications were recorded; the latter were categorized as minor if additional surgery was not necessary, and major if surgery was needed to resolve the complication. Bone healing was scored and change in tibial plateau angle (TPACH ) between postoperative and follow up radiographic images was calculated. Mean (± SD) preoperative TPA was 28.6 ± 3.8°, and mean postoperative TPA was 4.8 ± 1.9°. Four intraoperative complications (7.1%) including 2 cases of intra-articular screw placement, 3 minor postoperative complications (5.4%), and no major or catastrophic postoperative complications occurred. Median bone healing grade was 4/4 (excellent union &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;75% healing). Mean TPACH was 0.15 ± 1.32°. Use of this anatomically contoured, locking TPLO plate by experienced surgeons is associated with accurate tibial plateau leveling, reliably excellent bone union at follow-up exam, minimal TPACH , and a lower complication rate than previously reported. Confining contouring to the distal shaft of the plate ensures there is precise apposition to the tibial diaphysis and mitigates the risk of intra-articular screw placement.
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SummaryComplete or partial rupture of the cranial cruciate ligament (CCL) is a common injury of the canine stifle. While numerous techniques have been developed for surgical treatment, extra-articular methods with placement of a lateral... more
SummaryComplete or partial rupture of the cranial cruciate ligament (CCL) is a common injury of the canine stifle. While numerous techniques have been developed for surgical treatment, extra-articular methods with placement of a lateral suture remain a popular treatment method. The purpose of this study was to determine the potential isometry of the six suture-paired sites two on the femur and three on the tibia. In six femoro-tibial specimens with intact passive joint restraints, femoral sites adjacent to the proximal (F1) and distal (F2) poles of the fabella, and tibial sites adjacent to the patella insertion (T1), immediately cranial to (T2) and caudal to (T3) the long digital extensor tendon, were identified. A suture from one femoral site to one tibial site was placed under 0 or 5 N of preload, and tension was measured at joint angles of 150°, 130°, 90° and 50°. The F2-T3 combination was found to be most isometric. Isometry was reassessed in the same specimens with the suture i...
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An amendment to this paper has been published and can be accessed via the original article.
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Objective The aim of this study was to evaluate objective limb function using force plate gait analysis after tibial plateau levelling osteotomy (TPLO) in small breed dogs with cranial cruciate ligament rupture (CCLR). Materials and... more
Objective The aim of this study was to evaluate objective limb function using force plate gait analysis after tibial plateau levelling osteotomy (TPLO) in small breed dogs with cranial cruciate ligament rupture (CCLR). Materials and Methods Small breed dogs (15 kg or less) with unilateral CCLR treated with TPLO were evaluated using symmetry index (SI) of peak vertical force (PVF), vertical impulse and vector magnitude at PVF performed preoperatively and at 1, 2, 4 and 6 months postoperatively after routine TPLO surgery. Results Twelve dogs met the inclusion criteria. Hindlimb function was markedly improved after TPLO, with all three postoperative SI significantly higher after a month than preoperative values (p