Mike Conzemius

University of Minnesota Twin Cities | UMN · Department of Veterinary Clinical Sciences

Case series summary Three cats (five stifles) were diagnosed with varying degrees of pelvic limb lameness secondary to medial patellar luxations (MPLs). Lameness did not resolve with medical management in any cat before referral for orthopedic evaluation. All cats underwent semi-cylindrical recession trochleoplasty (SCRT), medial fascial release an...

Objective Pain management is an essential component of perioperative patient care. Multimodal pain management strategies have the potential to provide more effective analgesia than a single drug. The objective of this study was to evaluate the use of gabapentin as an adjuvant to carprofen for the management of postoperative pain following tibial pl...

Objective: To assess the 6-month outcome and survival of enhanced polyethylene terephthalate (PET) implants as a replacement for the cranial cruciate ligament (CCL) in dogs with spontaneous CCL disease (CCLD). Study design: Pilot, prospective case series. Animals: Ten client-owned large breed dogs with unilateral spontaneous CCLD. Methods: D...

The center of mass (CoM) is the location in a body where mass distribution is balanced. It has a fundamental role in balance and motion which has been poorly described in the dog. The objective of this study was to estimate the variance of the center of mass (CoM) in a heterogeneous population of client-owned dogs and to describe the relationship b...

Kinetic gait analysis and ground reaction forces (GRFs) have been used in hundreds of scientific manuscripts. Specific methodology, interpretation of results, and translation to clinical veterinary medicine have been inconsistent. This impedes the advance of veterinary medicine and poses a risk to patients. The objective of this report was to addre...

In 1952, an intraarticular (IA) repair was described utilizing a lateral fascia lateral graft placed through tibial and femoral bone tunnels and anchored with suture to the soft tissue external to the tunnels. The decline of IA repairs was likely a combination of personal observation of outcomes of IA repair compared to current extraarticular repai...

This chapter provides the information on pathology, diagnosis, and treatment goals of cranial cruciate ligament (CCL) rupture and defining complications. CCL disease is considered to be the most common cause of pelvic limb lameness in the canine, affecting approximately 2.55% of the population. The most likely etiology for rupture of the CCL in mat...

Objective The aim of this study was to describe an alternative method for trochleoplasty, semi-cylindrical recession trochleoplasty (SCRT), and compare it to trochlear block recession (TBR) in regard to recessed trochlear depth, patellar depth, patellar articular contact with the trochlea, recessed trochlear surface area, procedure time, complicati...

Objective The aim of this study was to investigate the effects of an induced incomplete ossification of the humeral condyle (IOHC) lesion on ex vivo canine humeral condylar biomechanics. Study Design Nine paired cadaveric elbows were collected from mature dogs weighing between 20 and 25 kg. Left and right limbs were randomized to IOHC or normal gro...

Cranial cruciate ligament rupture (CCLR) is one of the leading causes of pelvic limb lameness in dogs. About 6% of Labrador Retrievers suffer from this orthopedic problem. The aim of this study was to determine the heritability of CCLR in this breed using SNP array genotyping data. DNA samples were collected from CCLR‐affected dogs (n = 190) and un...

Objective: To assess the 12-month survival of intra-articular, decellularized allografts for the treatment of cranial cruciate ligament disease (CCLD) in dogs. Study design: Prospective case series. Animals: Twenty client-owned dogs with spontaneous CCL rupture. Methods: Affected stifles were treated solely by implantation of an intra-articu...

Introduction Current sports medicine textbooks suggest German Shepherd dogs leave a forelimb on the ground longer than other breeds for support because of angulated joints eliminating a true suspension phase (support trot). The objective of this study was to characterize the trot of healthy, adult German Shepherd dogs and describe morphometric rela...

The objective of this study was to explore the mathematical relationships between independent variables (patient morphometrics and treadmill speed) and dependent variables (accelerometer or pedometer output) when evaluating data from accelerometers and pedometers in dogs. Twenty dogs took part in 3 randomized activities, consisting of exercise on a...

The estimation of long-standing pain in companion animals through the measurement of different dimensions impacted by pain is a fundamental requirement if pain management, and pain therapeutic development, are to advance. Although pain management in veterinary medicine has advanced considerably in the last 20 years, there is much critical work to d...

In the face of increasing recognition and interest in treating chronic pain in companion animals, we struggle with a lack of therapeutic options. A significant barrier to the development of new therapeutics, or the critical evaluation of current therapies, is our inability to accurately measure chronic pain and its impact on companion animals. Over...

Objective The aim of this study was to measure and compare sub-bandage pressures after a rigid splint was applied to the forelimb of a dog by surgeons and veterinary students. Animals One, adult, Labrador Retriever. Methods Sub-bandage pressure was measured at five locations on the limb of a dog using a previously validated pneumatic compression me...

Objective The aim of this study was to determine if articulated joint distraction in the canine elbow can effectively maintain a distraction gap between the articular surfaces of the canine elbow under a weight-bearing load. Study Design An articulated external skeletal fixator with turnbuckles was applied to seven canine cadaveric elbow specimens....

Objective To determine the relationship between synovial biomarker concentrations and severity of lameness and to assess the ability to differentiate normal from osteoarthritic joints with synovial biomarker concentrations. Study design Prospective clinical study. Sample population Twelve hounds with no evidence of osteoarthritis (OA) and 27 clie...

Objective To measure tissue oxygen saturation (StO2) in a population of dogs with naturally occurring shock and to evaluate the relationship of StO2 with an established veterinary severity scoring system (Acute Patient Physiologic and Laboratory Evaluation) and patient survival. Design Prospective observational study. Setting University teaching...

In veterinary medicine, evaluation of osteoarthritis (OA) treatment efficacy remains challenging. Measurement of activity, utilizing accelerometers, provides a surrogate measure of pain through measuring effects on activity, and the objective data collected can be used to assess the efficacy of treatments. However, little is known about how dog cha...

Objective To determine the efficacy of oral extended‐release hydrocodone compared with oral firocoxib for analgesia following tibial plateau leveling osteotomy surgery in dogs in a hospital setting. Study design Prospective, randomized, blinded, clinical trial. Animals Thirty‐six client‐owned dogs weighing 25‐43 kg with unilateral hindlimb lamene...

Balanced and concurrent consideration of success and failure after stifle surgery should be used to define and explain how 'successful' a procedure is. To accomplish this, investigators must: understand how to calculate and report the successes and failures; carefully choose the outcome measure(s) used to measure success and failure; and evaluate a...

This chapter first identifies some potential limitations of commonly used surgical procedures for cruciate ligament rupture. It briefly explores the historic use of intra-articular repair in dogs, and then focuses on overcoming the identified limitations of both extra- and intra-articular repairs. The chapter provides a review of the literature add...

Veterinary clinical trials generate data that advance the transfer of knowledge from clinical research to clinical practice in human and veterinary settings. The translational success of non-regulated and regulated veterinary clinical studies is dependent upon the reliability and reproducibility of the data generated. Clinician-scientists that cond...

Objective To determine if environmental variables affect the average daily activity counts (AC) of dogs with osteoarthritis (OA) and/or owners' perception of their dog's clinical signs or quality of life. Methods The AC and Canine Brief Pain Inventory (CBPI) owner questionnaires of 62 dogs with OA were compared with daily environmental variables in...

Objectives: To assess the safety and efficacy of an orally administered nutraceutical (Glu/CS+; + for additional ingredient) for the treatment of clinical osteoarthritis (OA) in dogs. Methods: In this double-blind, randomized, placebo-controlled clinical trial, client-owned dogs with clinical signs of OA in one or more joints were assigned to a...

Objective: To determine the 12-month outcome in dogs with spontaneous cranial cruciate ligament (CCL) rupture after repair with an intra-articular decellularized allograft. Study design: Prospective pilot case series. Animals: Ten client-owned dogs with unilateral CCL rupture. Methods: An intra-articular, decellularized, deep digital flexor...

Background: Exercise-induced collapse (EIC) due to DNM1 mutation and rupture of the cranial cruciate ligament are both common syndromes in the Labrador retriever breed. A cohort of 313 Labradors was recruited based on their CCLR status and were subsequently genetically tested for EIC. Epidemiological aspects of the cohort were also described, incl...

p> Objective: The primary objective of this study was to identify adverse events associated with multiple intra-articular injections of adipose stromal cell (ASC) therapy and secondarily to objectively assess the therapeutic effect of ASC therapy for treatment of fragmented medial coronoid process (FMCP) in dogs when used as an adjuvant to standard...

Objective: To evaluate the biochemical and biomechanical properties of native and decellularized superficial digital flexor tendons (SDFTs) and deep digital flexor tendons (DDFTs) harvested from the pelvic limbs of orthopedically normal dogs. Sample: 22 commercially supplied tendon specimens (10 SDFT and 12 DDFT) harvested from the pelvic limbs...

The objective of this study was to subjectively evaluate the harvest of two areas of adipose collection and three areas of bone marrow collection as potential sites for clinical harvest of adipose stromal vascular fraction (SVF) and bone marrow concentrate for clinical use by quantifying the amount of tissue harvested, subjective ease of harvest, t...

Introduction Stem cell therapy used in clinical application of osteoarthritis in veterinary medicine typically involves intra-articular injection of the cells, however the effect of an osteoarthritic environment on the fate of the cells has not been investigated. Aims and Objectives Assess the viability of adipose derived stromal cells following ex...

Objective: To test ex vivo mechanical properties of 4 allograft fixation techniques for cranial cruciate ligament (CCL) replacement. Sample: 30 stifle joints from canine cadavers. Procedures: CCL-deficient stifle joints repaired by 1 of 4 techniques (n = 6/group) and CCL-intact stifle joints (control group; 6) were mechanically tested. Three r...

Objective To evaluate the relationship between tibial plateau angle (TPA) and strain in the intact cranial cruciate ligament (CCL) during axial loading. Study DesignEx vivo mechanical testing study. Sample PopulationCadaveric canine stifles (n=6). MethodsA bicentric and uni-radial Slocum saw blade was used to perform the osteotomy on each stifle an...

To test the ex vivo mechanical properties of canine patella-ligament-tibia (PLT) segment and establish the relationship between donor size and PLT dimensions to the mechanical properties of PLT grafts. Ex vivo mechanical testing study. Canine PLT segments (n = 21 dogs; 42 PLT). Morphometric measurements of PLT segments were taken from computed tomo...

Objective: To evaluate the effects of perioperative oral administration of tramadol, firocoxib, and a tramadol-firocoxib combination on signs of pain and limb function after tibial plateau leveling osteotomy in dogs. Design: Randomized, blinded, prospective clinical trial. Animals: 30 adult client-owned dogs with unilateral cranial cruciate li...

Objective: To determine short- and long-term rates of successful outcomes of surgical and nonsurgical treatments for overweight dogs with cranial cruciate ligament rupture (CCLR). Design: Prospective, randomized, clinical trial. Animals-40 client-owned overweight dogs with unilateral CCLR. Procedures: Dogs were randomly assigned to nonsurgical...

To measure the loads required to induce lateral luxation of the Iowa State University (ISU) elbow implant, a modified elbow implant, and the normal canine elbow with the ligaments and joint capsule removed. Mechanical testing on cadaveric specimens Twelve thoracic limbs were harvested from adult, medium sized dogs that had been euthanatized for rea...

Objective: To document the caregiver placebo effect in owners and veterinarians of dogs with lameness from osteoarthritis. Design: Prospective, randomized, double-blinded, placebo-controlled, multicenter clinical trial. Animals: 58 dogs with lameness secondary to osteoarthritis. Procedures: Dogs enrolled in the placebo arm of an FDA-approved...

Follicular thyroid carcinoma (FTC) is an aggressive tumour in dogs with little known about its molecular pathogenesis. The overall goal of this study was to examine FTC and normal thyroid tissue gene expression. Microarray analysis was performed on a pilot group of five FTC-affected dogs and four healthy dogs, and then osteopontin validated with qu...

Commonly used diagnostic tools used to evaluate articular cartilage lack the sensitivity, specificity, and objectivity to measure early changes associated with osteoarthritis. Two techniques using magnetic resonance (MR) imaging have been developed to detect the biology of articular cartilage are delayed gadolinium-enhanced MR imaging of cartilage...

To determine (1) if braided, polyblend orthopedic suture materials are mechanically superior to monofilament nylon leader and (2) have mechanical properties similar to biomechanical properties of the canine cruciate ligament. Different suture material types. Mechanical testing was performed on 5 different orthopedic suture materials: 80# test Mason...

Investigation of femoral head osteonecrosis would benefit from an animal model whose natural history includes progression to bony collapse of a segmental necrotic lesion. The bipedal emu holds attraction for systematic organ-level study of collapse mechanopathology. One established method of experimentally inducing segmental lesions is liquid nitro...

To determine growth of the proximal tibial physis in the Labrador Retriever, a breed of dog at risk for rupture of the cranial cruciate ligament (CCL). Male Labrador Retriever dogs (n=6). Tantalum markers (0.5 mm diameter) were implanted in the right proximal tibial epiphysis and metaphysis of each dog at 16 weeks of age. Lateral and craniocaudal r...

Osteomyelitis contributes significantly to fracture morbidity. Our objective was to develop a model of induced implant-associated osteomyelitis following fracture repair by modifying an existing rat femur fracture model. Thirty male Sprague-Dawley rats were divided into three groups (Control, Staphylococcus aureus, S. aureus + ceftriaxone). The clo...

To determine the relationship between serum cortisol concentration and pain severity as measured by force platform gait analysis in dogs with experimentally induced synovitis of the stifle joint. 10 healthy hound-type dogs. Dogs underwent 2 study phases. In the first phase, serum cortisol concentration, systolic arterial blood pressure, heart rate,...

Introduction: Subjective measures such as owner questionnaires are commonly used and while useful, they add bias. That bias is called the care-giver placebo effect. In uncontrolled studies the bias may inflate or deflate the perceived effect of treatment thereby causing unwarranted changes in clinical practice. The objective of this study was to do...

The objectives of this study were to determine the frequency of incomplete ossification of the contralateral humeral condyle (IOHC) in mature dogs with unilateral, atraumatic humeral condylar fracture (HCF), and to determine the sensitivity of radiographs as a diagnostic tool for IOHC. Computed tomography and radiographs were obtained for both elbo...

Introduction: Cranial cruciate ligament rupture (CCLR) continues to be one the most prevalent and debilitating canine orthopedic diseases. Typically, surgery is recommended for management of CCLR although there is a lack of a prospective direct comparison of surgical management vs medical management of CCLR for functional outcome and osteoarthritis...

Introduction: There is increasing interest in using stem cell therapy for clinical use in small animal surgery. This study is the first known examination of characterizing mesenchymal stem cells (MSCs) derived from bone marrow and adipose tissue in the canine. This study also compares collection sites and provides information on the best tissue and...

Introduction: Stem cell treatment in the canine utilizes a stromal vascular fraction, containing in part, adipose-derived mesenchymal stem cells. The characterization and standardization of components and mechanisms of effective outcomes is lacking. Stem cells are suspected to mediate outcome through paracrine effects, immunomodulating the inflamma...

Objective —To determine the spatiotemporal gait characteristics and associated covariates of clinically normal dogs and dogs with spinal cord disease. Animals —42 clinically normal dogs and 24 dogs with myelopathy at spinal cord segment T3-L3. Procedures —Gait was analyzed for velocity, stride length, stride time, stance time, and swing time and co...

Bacterial infections are a costly sequela in any wound. The corrosion properties of 0.15, 0.30, 0.45 and 0.60 g of Mg metal were determined in Mueller-Hinton broth by serially measuring the Mg(2+) concentrations and pH over 72 h. In addition, the effect of Mg metal, increased Mg(2+) concentration and alkaline pH on the in vitro growth of Escherichi...

To identify chromosomal regions associated with cranial cruciate ligament rupture (CCLR) in a population of Newfoundlands. 90 client-owned Newfoundlands. A pedigree was constructed for dogs that did or did not have CCLR (determined on the basis of physical examination and radiographic findings). From this pedigree, affected and unaffected dogs were...

Osteonecrosis of the femoral head remains a challenging orthopaedic problem. The disease frequently progresses to femoral head collapse, leading to debilitating osteoarthritis in the affected hip(s). Since a major goal of pre-collapse interventions is to forestall the need for hip arthroplasty, it is important that any animal models used to develop...

Outcome measures for functional assessment in experimental or naturally occurring spinal cord injury (SCI) in dogs have been largely subjective. This study is the first step in developing an easy, accurate, and objective outcome measure for neurologic dogs. The hypothesis was that the coefficient of variation (CV) of spatiotemporal parameters of ga...

To review development of a nonconstrained total elbow replacement system for use in dogs and report the surgical technique used for implantation. Descriptive report. Dogs with chronic elbow osteoarthritis (OA) unresponsive to medical management for at least 1 year. A nonconstrained elbow replacement system (radioulnar and humeral components) was de...

This study investigated the effect of fibroblast growth factor 2 in monolayer followed by transforming growth factor 1 in 3-dimensional culture on chondrocytic matrix production. Under the culture conditions presented, FGF2 is mitogenic but not chondrogenic. In addition, TGF1 stimulation produced predominantly type I collagen.

To evaluate the relationship between previously used subjective and objective measures of limb function in normal dogs that had an induced lameness. Prospective, blinded, and induced animal model trial. Normal, adult, and mixed-breed dogs (n=24) weighing 25-35 kg. Force platform gait analysis was collected in all dogs before and after induction of...

Cryoinsult-induced osteonecrosis (ON) in the emu femoral head provides a unique opportunity to systematically explore the pathogenesis of ON in an animal model that progresses to human-like femoral head collapse. Among the various characteristics of cryoinsult, the maximally cold temperature attained is one plausible determinant of tissue necrosis....

The objective of this review and analysis was to compare arthroscopy, medial arthrotomy and medical management for treating fragmented coronoid process in the dog. The data come from manuscripts published in peer-reviewed veterinary journals, and the study design is a systematic review followed by meta-analysis. The meta-analysis combines data from...

The emu is a large, (bipedal) flightless bird that potentially can be used to study various orthopaedic disorders in which load protection of the experimental limb is a limitation of quadrupedal models. An anatomy-based analysis of normal emu walking gait was undertaken to determine hip contact forces for comparison with human data. Kinematic and k...

To evaluate short-term postoperative forelimb function after scalpel and laser onychectomy in cats. Randomized, prospective study. 20 healthy adult cats. Cats were randomly assigned to the laser (n = 10) or scalpel (10) onychectomy group. Unilateral left forelimb onychectomy was performed. In the scalpel group, a tourniquet was used during surgery...

Orthopaedic management of femoral head osteonecrosis remains problematic, partly because of inability to systematically compare treatments in an animal model whose natural history parallels the human in terms of progression to femoral head collapse. Recently, it was determined that collapse could be consistently achieved for cryogenically induced o...

A total of 249 client-owned dogs with osteoarthritis were treated with firocoxib (5 mg/kg/day) or a positive control, etodolac (10-15 mg/kg/day), for 30 days. Veterinary examinations were performed on approximately days 0 (visit 1), 14 (visit 2), and 29 (visit 3). Based on defined noninferiority criteria, firocoxib and etodolac were comparable. Bas...

To assess the relationship between postoperative tibial plateau angle (TPA) and ground reaction forces (GRFs) in Labrador Retrievers at least 4-months after tibial plateau leveling osteotomy (TPLO) surgery. A retrospective longitudinal study. Thirty-two Labrador Retrievers with unilateral cranial cruciate ligament disease that had TPLO and concurre...

To determine prevalence, level of inbreeding, heritability, and mode of inheritance for rupture of the cranial cruciate ligament (RCCL) in Newfoundlands. Retrospective and recruitment study. 574 client-owned Newfoundlands. Medical records from January 1, 1996, to December 31, 2002, were evaluated for prevalence of RCCL. A pedigree was constructed b...

Systematic studies of treatment options for femoral head osteonecrosis have been hindered by the lack of an animal model that mimics the human event of femoral head collapse. The (bipedal) emu model of osteonecrosis has proven to progress to collapse following an external insult. Since osteonecrosis clinically has multiple etiologies, various alter...

To estimate the economic impact to veterinary clients for the medical and surgical treatment of rupture of the cranial cruciate ligament (RCCL) in dogs for the year 2003. Economic impact survey. 501 diplomates of the American College of Veterinary Surgeons (ACVS) indicating that their area of surgical emphasis was small animal orthopedic surgery or...

Mesenchymal stem cells or chondrocytes have been implanted into joints in biodegradable matrices in order to improve the quality of healing cartilage defects; however, insufficient biomechanical strength of the construct at implantation is a limiting factor for clinical application. Logically, a construct with better biomechanical characteristics w...

Total joint replacement has evolved over the past 50 years from a concept that was first attempted in people suffering from osteoarthritis to a commonly applied practice in veterinary medicine. Although many questions have been answered, several controversies still exist, with many implant and technical options being explored. Currently, total hip...

To determine the combination of ground reaction forces (GRFs) that best discriminates between lame and non-lame dogs. To compare the sensitivity of force platform gait analysis and visual observation at detecting gait abnormalities in Labradors after surgery for rupture of the cranial cruciate ligament (CCL). All dogs were adult Labrador Retrievers...

To evaluate the analgesic effects of topical administration of bupivacaine, i.m. administration of butorphanol, and transdermal administration of fentanyl in cats undergoing onychectomy. Prospective study. 27 healthy adult cats. Cats were randomly assigned to 1 of 3 treatment groups, and unilateral (left forefoot) onychectomy was performed. Gait an...

Extracorporeal shockwave therapy (ESWT) has expanded from the original uses of human urinary calculi treatment to veterinary orthopaedic applications. This paper investigates the feasibility and efficacy of treating dogs with osteoarthritis of the stifle joint with ESWT. In this study, dogs with persistent stifle lameness despite previous surgical...

To determine the outcome and effect of surgical technique on limb function after surgery for rupture of the cranial cruciate ligament (RCCL) and injury to the medial meniscus in Labrador Retrievers. Prospective clinical study. 131 Labrador Retrievers with unilateral RCCL and injury to the medial meniscus and 17 clinically normal Labrador Retrievers...

Providing pain relief after onychectomies in cats is a must, and you have many options. Choosing which drug to use can be confusing, but, in general, a multimodal approach seems best.

To document peak vertical force (PVF) and vertical impulse (VI) in the pads of Greyhounds and Labrador Retrievers. 8 Greyhounds and 8 Labrador Retrievers. Velocity and acceleration were restricted to ranges of 0.9 to 1.1 m/s and -0.1 to 0.1 m/s2, respectively. The PVF and VI measurements were collected from digital pad (DP)-2, -3, -4, and -5 and th...

Osteoarthritis is a significant problem for a large number of veterinary patients, particularly as they get older. A group of leading specialists were gathered to outline current thinking on the approach to this disease and their recommendations for its management.

To determine peak vertical force (PVF) and vertical impulse (VI) in cats that had or had not undergone bilateral forelimb onychectomy. 26 healthy adult cats. Onychectomized cats (n = 13) had undergone surgery more than 6 months prior to the study. The PVF and VI were collected from all limbs of each cat with a 2-m pressure platform walkway. Cats we...

To observe differences in surgical and healing times as well as complication rates in dogs with a comminuted long-bone fracture stabilized with an interlocking nail (IN) using either anatomic or biologic repair. Retrospective study. Twenty client-owned dogs with comminuted long-bone fractures. Medical records for dogs with fractures repaired during...

To document, using pressure platform gait analysis, the effect of perioperative oral carprofen on limb function and pain after cranial cruciate ligament surgery in dogs. Blinded, prospective clinical investigation. Twenty dogs with naturally occurring unilateral cranial cruciate disease. Physiologic indices, subjective pain scoring, and pressure pl...

Femoral head osteonecrosis is often characterized histologically by the presence of empty lacunae in the affected bony regions. The shape, size and location of a necrotic lesion influences prognosis, and can, in principle, be quantified by mapping the distribution of empty lacunae within a femoral head. An algorithm is here described that automatic...