About

David Knazovicky is an Assistant Professor of Small Animal Orthopedics at NC State University’s College of Veterinary Medicine. He began his career at NC State in 2013 as a Research Assistant in the Comparative Pain Research Laboratory and has since advanced through a Small Animal Rotating Internship, a Small Animal Surgery residency, and a role as a Clinical Veterinarian in Orthopedics and Rehabilitation. His foundational training includes a Doctor of Veterinary Medicine and a PhD from the University of Veterinary Medicine in Košice, Slovakia. With over a decade of clinical, research, and teaching engagement at NC State, his work is dedicated to advancing small animal orthopedics and improving patient outcomes through evidence-based practice. His clinical focus centers on small animal orthopedic diseases, with a secondary specialty in joint replacement surgery. He serves as a senior clinician on the Small Animal Orthopedics Service, providing supervision, clinical instruction, and case management for veterinary students and surgical house officers. He performs the majority of Total Hip Replacements at NC State and is completing a Fellowship in Joint Replacement Surgery. His expertise includes total hip replacement surgery, cranial cruciate ligament disease, management of complex orthopedic and musculoskeletal conditions, and management of complex fractures and ligament injuries.

Research topics

• Medicine
• Psychology
• Neuroscience
• Audiology
• Cognitive psychology
• Immunology
• Oncology
• Pathology
• Internal medicine

Selected publications

• Quantitative sensory testing in dogs with spontaneous osteoarthritis

  Frontiers in Pain Research · 2025-04-14 · 1 citations

  articleOpen access

  Objective: To investigate changes in somatosensory sensitivity in dogs with spontaneous osteoarthritis (OA) and pain of the stifle or hip, compared to a group of healthy control dogs. Study design: A non-randomised, non-blinded, prospective research study. Animals: 30 control, 51 OA-pain, and 31 OA-pain dogs receiving NSAIDs. Methods: A range of noxious and non-noxious quantitative sensory testing (QST) modalities were applied. Dogs were tested twice, one month apart. Two sites were tested at each visit: a distal site located on the cranial aspect of the mid metatarsus and a primary site, lateral to the patella (in dogs with stifle OA) or craniodorsally to the greater trochanter (in dogs with coxofemoral OA). Control dogs were tested at appropriate primary sites to produce the same proportion of animals being tested at stifle or hip as those in the OA group. The order in which non-nociceptive and nociceptive tests were performed was randomized for each test site for each animal, although nociceptive tests were always performed after non-nociceptive tests. Feasibility for performing the tests was assessed for the final 45 dogs recruited to the study. The hierarchical structure of the QST testing data was accounted for within the statistical analysis by employing general linear modelling within a multilevel modelling framework using the MLwiN statistics package. Results: Osteoarthritis category was not a major determinant of QST outcome measures for the majority of modalities evaluated. In the few modalities in which OA category was determined to be a significant predictor variable, the results were not consistent with previously reported data. The novel, non-nociceptive tests employed overall suggested non-noxious hypoesthesia in association with OA pain. The feasibility of performing QST assessments was relatively low compared to previous studies. Conclusions: and clinical relevance: In a clinical environment, the variability in feasibility of performing QST between dogs may be sufficient to confound changes in QST outcome measures associated with spontaneous OA.

  PublisherOA PDFDOI

• Ice water immersion does not activate diffuse noxious inhibitory controls of spinal reflexes in sedated or anaesthetised dogs (Canis familiaris): a pilot study

  Frontiers in Pain Research · 2025-03-10

  articleOpen access

  Introduction Diffuse noxious inhibitory controls (DNIC) may be impaired in human subjects with osteoarthritis (OA) pain. Spontaneously occurring OA in dogs is considered a valuable model of human OA; however, methodology for assessing DNIC in dogs has not been fully developed. The aim of this study was to develop a suitable DNIC protocol using ice water immersion, similar to protocols used in humans. Objective This study objective was to create an experimental protocol for inducing DNIC in sedated or anesthetized dogs, ensuring it has face validity for future assessments of DNIC in studies involving the spontaneous canine OA model. We hypothesized that inducing DNIC in healthy dogs would result in a reduced electromyographic (EMG) response to a specific nociceptive stimulus. Methods Electromyographic (EMG) responses of the cranial tibial muscle to test electrical stimuli and interdigital skin temperature were recorded in seven healthy dogs before and during a 20-min duration conditioning ice water immersion of the distal forelimb. The protocol was repeated for each dog using three different states: sedation with acepromazine or alfaxalone or anaesthesia with alfaxalone. Results Ice water immersion caused a decrease of interdigital skin temperature in dogs in all three groups with the nadir (4.9–13.6°C) at 10 min following immersion. Skin temperatures remained significantly higher ( p = 0.018) in alfaxalone sedated compared to acepromazine sedated dogs and returned to baseline more quickly than in acepromazine sedated dogs. Magnitudes of EMG responses were significantly larger in acepromazine sedated dogs compared to alfaxalone treated dogs ( p < 0.001). DNIC was not induced, as the EMG magnitude did not significantly change over time for either the early ( p = 0.07) or late responses ( p = 0.27), and no significant interactions were observed between time and anaesthetic state in relation to EMG magnitude. Conclusion Our data suggest that a cold conditioning stimulus failed to elicit DNIC. It is possible that the magnitude of the conditioning stimulus was not sufficient to recruit DNIC in dogs.

  PublisherOA PDFDOI

• Intra-Articular Pressures of the Shoulder and Stifle During Arthroscopy

  Veterinary and Comparative Orthopaedics and Traumatology · 2025-07-01

  articleSenior author
  PublisherDOI

• Ice water immersion does not activate diffuse noxious inhibitory controls of spinal reflexes in sedated or anaesthetised dogs (Canis familiaris): a pilot study

  UNC Libraries · 2025-04-02

  articleOpen access

  Introduction: Diffuse noxious inhibitory controls (DNIC) may be impaired in human subjects with osteoarthritis (OA) pain. Spontaneously occurring OA in dogs is considered a valuable model of human OA; however, methodology for assessing DNIC in dogs has not been fully developed. The aim of this study was to develop a suitable DNIC protocol using ice water immersion, similar to protocols used in humans. Objective: This study objective was to create an experimental protocol for inducing DNIC in sedated or anesthetized dogs, ensuring it has face validity for future assessments of DNIC in studies involving the spontaneous canine OA model. We hypothesized that inducing DNIC in healthy dogs would result in a reduced electromyographic (EMG) response to a specific nociceptive stimulus. Methods: Electromyographic (EMG) responses of the cranial tibial muscle to test electrical stimuli and interdigital skin temperature were recorded in seven healthy dogs before and during a 20-min duration conditioning ice water immersion of the distal forelimb. The protocol was repeated for each dog using three different states: sedation with acepromazine or alfaxalone or anaesthesia with alfaxalone. Results: Ice water immersion caused a decrease of interdigital skin temperature in dogs in all three groups with the nadir (4.9–13.6°C) at 10 min following immersion. Skin temperatures remained significantly higher (p = 0.018) in alfaxalone sedated compared to acepromazine sedated dogs and returned to baseline more quickly than in acepromazine sedated dogs. Magnitudes of EMG responses were significantly larger in acepromazine sedated dogs compared to alfaxalone treated dogs (p < 0.001). DNIC was not induced, as the EMG magnitude did not significantly change over time for either the early (p = 0.07) or late responses (p = 0.27), and no significant interactions were observed between time and anaesthetic state in relation to EMG magnitude. Conclusion: Our data suggest that a cold conditioning stimulus failed to elicit DNIC. It is possible that the magnitude of the conditioning stimulus was not sufficient to recruit DNIC in dogs.

  PublisherDOI

• Assessment of Sensory Thresholds in Dogs using Mechanical and Hot Thermal Quantitative Sensory Testing

  Journal of Visualized Experiments · 2021 · 4 citations

  • Medicine
  • Audiology
  • Neuroscience

  Quantitative sensory testing (QST) is used to evaluate the function of the somatosensory system in dogs by assessing the response to applied mechanical and thermal stimuli. QST is used to determine normal dogs' sensory thresholds and evaluate alterations in peripheral and central sensory pathways caused by various disease states, including osteoarthritis, spinal cord injury, and cranial cruciate ligament rupture. Mechanical sensory thresholds are measured by electronic von Frey anesthesiometers and pressure algometers. They are determined as the force at which the dog exhibits a response indicating conscious stimulus perception. Hot thermal sensory thresholds are the latency to respond to a fixed or ramped temperature stimulus applied by a contact thermode. Following a consistent protocol for performing QST and paying attention to details of the testing environment, procedure, and individual study subjects are critical for obtaining accurate QST results for dogs. Protocols for the standardized collection of QST data in dogs have not been described in detail. QST should be performed in a quiet, distraction-free environment that is comfortable for the dog, the QST operator, and the handler. Ensuring that the dog is calm, relaxed, and properly positioned for each measurement helps produce reliable, consistent responses to the stimuli and makes the testing process more manageable. The QST operator and handler should be familiar and comfortable with handling dogs and interpreting dogs' behavioral responses to potentially painful stimuli to determine the endpoint of testing, reduce stress, and maintain safety during the testing process.

  PublisherDOI

• Serum artemin is not correlated with sensitivity within dogs with naturally occurring osteoarthritis pain

  Scientific Reports · 2021 · 5 citations

  • Medicine
  • Internal medicine
  • Oncology

  Osteoarthritis (OA) pain is associated with peripheral and central sensitization in humans and results in widespread increased sensitivity across the body. Sensitization contributes to the OA-associated pain (OAP) state. We recently identified increased levels of an endogenous neurotrophic factor, artemin (ARTN), in dogs with OAP compared to healthy pain-free controls. Circulating ARTN released from damaged tissues in OA, may play a central role in widespread sensitivity and pain. However, the relationship between ARTN and somatosensory sensitivity remains unknown. The study aimed to assess the relationship between serum ARTN concentrations and measures of sensitivity in dogs with OAP using quantitative sensory testing. We hypothesized that there would be a positive association between circulating ARTN and increased sensitivity to mechanical and thermal stimuli in dogs with OAP. We used linear and logistic regression models to assess the relationship between ARTN, sensitization, and pain within a cohort of 43 dogs with spontaneous OAP. Serum ARTN was not associated with the degree of sensitization within dogs with OAP. Further, across dogs with varying OAP severity, we did not find any association between ARTN, and clinical measures of joint pain and disability. Although a relationship between ARTN and joint pain was not ruled out.

  PublisherDOI

• JoVE Video Dataset

  2021

  • Audiology
  • Psychology
  • Medicine

  Quantitative sensory testing (QST) is used to evaluate the function of the somatosensory system in dogs by assessing the response to applied mechanical and thermal stimuli. QST is used to determine normal dogs' sensory thresholds and evaluate alterations in peripheral and central sensory pathways caused by various disease states, including osteoarthritis, spinal cord injury, and cranial cruciate ligament rupture. Mechanical sensory thresholds are measured by electronic von Frey anesthesiometers and pressure algometers. They are determined as the force at which the dog exhibits a response indicating conscious stimulus perception. Hot thermal sensory thresholds are the latency to respond to a fixed or ramped temperature stimulus applied by a contact thermode. Following a consistent protocol for performing QST and paying attention to details of the testing environment, procedure, and individual study subjects are critical for obtaining accurate QST results for dogs. Protocols for the standardized collection of QST data in dogs have not been described in detail. QST should be performed in a quiet, distraction-free environment that is comfortable for the dog, the QST operator, and the handler. Ensuring that the dog is calm, relaxed, and properly positioned for each measurement helps produce reliable, consistent responses to the stimuli and makes the testing process more manageable. The QST operator and handler should be familiar and comfortable with handling dogs and interpreting dogs' behavioral responses to potentially painful stimuli to determine the endpoint of testing, reduce stress, and maintain safety during the testing process.

  PublisherDOI

• Alfaxalone Anaesthesia Facilitates Electrophysiological Recordings of Nociceptive Withdrawal Reflexes in Dogs (Canis familiaris)

  UNC Libraries · 2020-04-21

  articleOpen access

  Naturally occurring canine osteoarthritis represents a welfare issue for affected dogs (Canis familiaris), but is also considered very similar to human osteoarthritis and has therefore been proposed as a model of disease in humans. Central sensitisation is recognized in human osteoarthritis sufferers but identification in dogs is challenging. Electromyographic measurement of responses to nociceptive stimulation represents a potential means of investigating alterations in central nociceptive processing, and has been evaluated in conscious experimental dogs, but is likely to be aversive. Development of a suitable anaesthetic protocol in experimental dogs, which facilitated electrophysiological nociceptive withdrawal reflex assessment, may increase the acceptability of using the technique in owned dogs with naturally occurring osteoarthritis. Seven purpose bred male hound dogs underwent electromyographic recording sessions in each of three states: acepromazine sedation, alfaxalone sedation, and alfaxalone anaesthesia. Electromyographic responses to escalating mechanical and electrical, and repeated electrical, stimuli were recorded. Subsequently the integral of both early and late rectified responses was calculated. Natural logarithms of the integral values were analysed within and between the three states using multi level modeling. Alfaxalone increased nociceptive thresholds and decreased the magnitude of recorded responses, but characteristics of increasing responses with increasing stimulus magnitude were preserved. Behavioural signs of anxiety were noted in two out of seven dogs during recordings in the acepromazine sedated state. There were few significant differences in response magnitude or nociceptive threshold between the two alfaxalone states. Following acepromazine premedication, induction of anaesthesia with 1–2 mg kg-1 alfaxalone, followed by a continuous rate infusion in the range 0.075–0.1 mg kg-1 min-1 produced suitable conditions to enable assessment of spinal nociceptive processing in dogs, without subjecting them to potentially aversive experiences. This methodology may be appropriate for obtaining electrophysiological nociceptive withdrawal reflex data in client-owned dogs with naturally occurring osteoarthritis.

  PublisherDOI

• Initial evaluation of nighttime restlessness in a naturally occurring canine model of osteoarthritis pain

  UNC Libraries · 2020-11-07

  articleOpen accessSenior author

  Chronic pain due to osteoarthritis (OA) can lead to significant disruption of sleep and increased restlessness. Our objective was to assess whether naturally occurring canine OA is associated with nighttime restlessness and so has potential as a model of OA-associated sleep disturbance. The study was designed as a two-part prospective masked, placebo-controlled study using client-owned dogs (Part A n = 60; Part B n = 19). Inclusion criteria consisted of OA-associated joint pain and mobility impairment. The primary outcome measure for both parts was nighttime accelerometry. In Part B, quality of sleep was assessed using a clinical metrology instrument (Sleep and Night Time Restlessness Evaluation Score, SNoRE). Part A included dogs receiving two weeks of non-steroidal anti-inflammatory drug (NSAID) preceded with two weeks of no treatment. Part B was a crossover study, with NSAID/placebo administered for two weeks followed by a washout period of one week and another two weeks of NSAID/placebo. Repeated measures analysis of variance was used to assess differences between baseline and treatment. There were no significant changes in accelerometry-measured nighttime activity as a result of NSAID administration. SNoRE measures indicated significant improvements in aspects of the quality of nighttime sleep that did not involve obvious movement. These results reflect the few similar studies in human OA patients. Although accelerometry does not appear to be useful, this model has potential to model the human pain-related nighttime sleep disturbance, and other outcome measures should be explored in this model.

  PublisherDOI

• Widespread somatosensory sensitivity in naturally occurring canine model of osteoarthritis

  UNC Libraries · 2020-04-21

  articleOpen access

  Osteoarthritis (OA)-associated pain is a leading cause of disability. Central sensitization (CS), as a result of OA, is recognized as an important facet of human patients' chronic pain and has been measured in people using quantitative sensory testing (QST) testing. The spontaneous canine OA model has been suggested as a good translational model, but CS has not been explored in this model. In this study, QST was performed on dogs with and without spontaneous hip or stifle OA to determine whether OA is associated with CS in this model. Mechanical (von Frey and blunt pressure) and thermal (hot and cold) sensory thresholds obtained in dogs with chronic OA-associated pain (n = 31) were compared with those of normal dogs (n = 23). Dogs were phenotyped and joint-pain scored, and testing was performed at the OA-affected joint, cranial tibial muscle, and dorsal metatarsal region. QST summary data were evaluated using mixed-effect models to understand the influence of OA status and covariates, and dogs with OA and control dogs were compared. The presence of OA was strongly associated with hyperalgesia across all QST modalities at the index joint, cranial tibial muscle, and metatarsal site. Mechanical QST scores were significantly moderately negatively correlated with total joint-pain scores. The spontaneous canine OA model is associated with somatosensory sensitivity, likely indicative of CS. These data further validate the canine spontaneous OA model as an appropriate model of the human OA pain condition.

  PublisherDOI

Frequent coauthors

• B. Duncan X. Lascelles

  North Carolina State University

  39 shared

• Beth Case

  MedStar Washington Hospital Center

  28 shared

• Margaret E. Gruen

  North Carolina State University

  21 shared

• William Maixner

  DaVita Clinical Research (United States)

  20 shared

• Erika S. Helgeson

  University of Minnesota

  19 shared

• Mila Freire

  Instituto de Instrumentación para Imagen Molecular

  9 shared

• Andrea Thomson

  North Carolina State University

  6 shared

• Valent Ledecký

  University of Veterinary Medicine in Košice

  5 shared

Labs

• Small Animal OrthopedicsPI

Education

• Ph.D., Comparative Medicine

  North Carolina State University

  2004

• M.S., Comparative Medicine

  University of California, Davis

  1999

• B.S., Animal Science

  University of California, Davis

  1997