Biomedical subjects

K K Haussler

Publications and source records attributed to K K Haussler.

11 recordsLinked to original sources

PubMed2006

Pressure algometry for the detection of induced back pain in horses: a preliminary study.

REASONS FOR PERFORMING STUDY: Pressure algometry (PA) is a potential modality for objectively measuring mechanical nociceptive thresholds (MNTs) in horses. Its ability to differentiate musculoskeletal pain sites from nonpain sites is unknown and must be assessed prior to its clinical application. OBJECTIVES: To assess the ability of PA to detect induced musculoskeletal pain. METHODS: Twenty clinically normal mature horses (2 groups of 10 horses, over 2 years) were used to measure MNTs before and after implantation and removal of 2 fixation half-pins in the dorsal spinous processes of 2 adjacent vertebrae. To assess hyperalgesia, MNTs near the surgical sites were pooled and compared to surrounding landmarks. MNTs were also compared on 2 consecutive days immediately after surgical implantation. To assess longer-term adaptation or sensitisation, changes from the beginning to the end of the study were evaluated. RESULTS: The precise surgical sites could be recognised due to substantial and localised decreases in the MNTs compared with surrounding landmarks. At most sites distant to the surgical sites, the distribution of the median percentage change in MNTs was centred around 0 (suggesting unbiased repeatability). MNTs compared from the beginning to the end of this study did not demonstrate obvious adaptation or sensitisation. CONCLUSIONS AND POTENTIAL RELEVANCE: PA provides a quantitative and repeatable method for assessing the presence of musculoskeletal pain. Further studies are needed to evaluate PA clinically for assessing musculoskeletal injuries and pain management strategies in horses.

Animals↗

PubMed2006

Mechanical nociceptive thresholds in the axial skeleton of horses.

REASONS FOR PERFORMING STUDY: An objective measure of neck, back and croup pain is needed in horses with musculoskeletal injuries, vague upper limb lameness or poor performance. OBJECTIVES: To establish mechanical nociceptive thresholds (MNTs) within the axial skeleton and evaluate the effects of subject status and ridden exercise. METHODS: Thirty-six mature horses (10 nonridden; 26 actively ridden) were used to assess MNTs evoked by a pressure algometer (PA) with a 1 cm2 rubber plunger tip at 62 midline and bilaterally symmetrical anatomical landmarks along the axial skeleton. Pressure was applied at a uniform rate of application until a local avoidance reaction was noted. The repeatability of 3 consecutive measurements was evaluated. Left-to-right comparisons and the effects of subject status and ridden exercise on MNTs were assessed. RESULTS: MNTs were repeatable and increased in a cranial-to-caudal gradient within the axial skeleton. Typically, there were no significant left-to-right differences. Within-horse variability was less than between-horse variability. Higher MNTs were measured in young, heavy, non-Thoroughbred, castrated males, and in horses that were ridden and actively exercised. CONCLUSIONS AND POTENTIAL RELEVANCE: PA provides an objective, noninvasive, and repeatable tool to measure mechanical nociception in horses. MNTs vary in horses with differing subject status and ridden exercise level.

Age Factors↗

PubMed2004

Development and validation of a periarticular injection technique of the sacroiliac joint in horses.

REASONS FOR PERFORMING STUDY: Sacroiliac joint osteoarthritis has been recognised as a significant cause of poor performance in competition and racehorses. Reliable diagnostic tools are currently lacking. The diagnosis has been based typically on exclusion of other possible causes of poor performance, back pain and hindlimb lameness. OBJECTIVES: To develop a safe, reliable and minimally invasive periarticular or intra-articular injection technique of potential use for diagnosis and therapy of sacroiliac joint disease in horses. METHODS: Twenty-six horses were used to develop and assess a medial approach to the sacroiliac joint with a 15 gauge, 25 cm long spinal needle. In Part I, the cadaveric study, the spinal needle was introduced cranial to the contralateral tuber sacrale and advanced along the medial aspect of the ipsilateral iliac wing until the dorsal surface of the sacrum was encountered. One ml methylene blue (MB) was injected in both sacroiliac joint regions of the sacropelvic specimens. The location of MB-stained tissues relative to the sacroiliac joints was recorded after dissection and disarticulation of the sacroiliac joint. In Part II, the in vivo study, 18 horses were used to validate the in vivo application of the sacroiliac joint injection technique. Horses were restrained in stocks and sedated in preparation for needle placement. One ml MB was injected bilaterally prior to euthanasia. Stained tissues were identified and recorded at necropsy. Successful joint injections were characterised as having MB located intra-articularly or < or = 2 cm periarticularly from the sacroiliac joint margin and localised to the middle or caudal third of the sacroiliac joint. RESULTS: Intra-articular MB was not observed in any specimen. However, MB-stained tissue was identified periarticularly in all injection sites (n = 48). Based on the predetermined success criteria, 96% of the methylene blue depots were located at the middle or caudal third of the sacroiliac joint. Dye-stained tissue was located < or = 2 cm from the sacroiliac joint margins in 88% of the specimens. Median distance of the MB from the sacroiliac joint margins was 1.0 cm (range 0.2-3.8 cm). The overall success rate considering both location and distance of the MB-stained tissue relative to sacroiliac joint margins was 83% (40 of 48 joints). CONCLUSIONS: The injection technique provides a reliable, easy to perform and consistent access to the medial periarticular aspect of the sacroiliac joint. POTENTIAL RELEVANCE: The described injection technique has the potential for both diagnostic and therapeutic applications in the medical management of equine sacroiliac joint disease. Further investigation is necessary to evaluate clinical efficacy and potential adverse effects.

Animals↗

PubMed2001

Frontier medicine: the future and integrative medicine.

Vigorous and prolonged effort is required to gain true mastery of the healing arts. Conventional and complementary medicine have complementary strengths and weaknesses. Like the yin and yang of traditional Chinese medicine, they naturally flow into one another by a process of induction, creating balance. Integrative medicine is the frontier; it is the future. If we are to progress beyond our current understanding and ability to heal, we must work with theoretic models that allow us and our perception to operate "outside the box." For some, this understanding is intuitive. It is through cooperative and collaborative efforts of intuitively adept and technologically adept minds that we can integrate and advance our understanding; increase our ability to predict, prevent, and diagnose disease; and expand our therapeutic options.

Animals↗

PubMed2001

Segmental in vivo vertebral kinematics at the walk, trot and canter: a preliminary study.

Understanding the pathophysiology of equine back problems, for clinical evaluation, treatment or injury prevention, requires understanding of the normal 3-dimensional motion characteristics of the vertebral column. Recent studies have investigated regional vertebral kinematics; however, there are no reported measures of direct in vivo segmental vertebral kinematics in exercising horses. Relative movements between 2 adjacent vertebrae were recorded for 3 horses that were clinically sound and did not have a known history of a back problem. A transducer consisting of 2 fixtures and an array of liquid metal strain gauges (LMSGs) was used to measure 3-dimensional segmental vertebral motion. The transducer was attached directly to Steinmann pins implanted in the dorsal spinous processes of adjacent vertebrae in 3 vertebral regions: thoracic (T14 to T16), lumbar (L1 to L3) and lumbosacral (L6 to S2). Rotational displacements between adjacent vertebrae were calculated from the differential outputs of the LMSG array during walk, trot and canter on a treadmill. Peak magnitudes of dorsoventral flexion, lateral bending and axial rotation were recorded continuously for each stride. The largest motion of the 3 instrumented vertebral segments was at the lumbosacral junction. In general, the greatest magnitude of segmental vertebral motion occurred during the canter and the least during the trot. The dynamic and continuous measure of 3-dimensional in vivo segmental vertebral motion provides an important new perspective for evaluating vertebral motion and back problems in horses.

Animals↗

PubMed1999

Anatomy of the thoracolumbar vertebral region.

A thorough understanding of the structure and function of the equine vertebral column can provide a clearer understanding of thoracolumbar spinal disorders. Three primary functions of the vertebral column include protection of the spinal cord, support for weight bearing, and flexibility for locomotion. Osseous structures provide structural support and vary from one vertebral region to another as functional requirements change. The spinal musculature produces complex vertebral movements while the spinal ligaments provide stability to the vertebral column. Proprioception and nociception are two important neurologic functions of the vertebral articulations.

Animals↗

PubMed1999

Osseous spinal pathology.

Pathologic changes have been observed at the spinous processes, intervertebral articulations, and sacroiliac joints in horses. Varying severity of degenerative articular changes are found in many articular processes, intertransverse, lumbosacral, and sacroiliac joints. Pathologic lesions tend to affect multiple vertebral locations within a specimen. Further studies need to be conducted to evaluate the clinical significance of the numerous vertebral and pelvic pathologic findings found in a sample of Thoroughbred racehorses that died because of unrelated injuries. Increased knowledge of osseous pathology inherent in equine athletes will enhance our understanding of the etiopathogenesis of spinal disorders and back pain in horses.

Animals↗

PubMed1999

Back problems. Chiropractic evaluation and management.

A thorough knowledge of equine spinal anatomy, biomechanics, and potential pathology is required to understand the principles and theories behind chiropractic and to apply its techniques properly. Chiropractic provides additional diagnostic and therapeutic means that may help equine practitioners to identify and treat the primary cause of lameness or poor performance. Specialized training in the evaluation and treatment of vertebral joint dysfunction and neuromusculoskeletal disorders places chiropractic in the forefront of conservative treatment of spinal-related disorders. Nevertheless, limited research is currently available on equine chiropractic and other nontraditional modalities in veterinary medicine. In 1996, the American Veterinary Medicine Association's Committee on Alternative and Complementary Therapies suggested that the research community should be encouraged to prioritize avenues of research and to allocate research funds to projects that are designed to provide further scientific evaluation of these modalities. The future of equine chiropractic in veterinary medicine is dependent on future research into the clinical effects of chiropractic techniques and the basic pathophysiology of spinal-related disorders in horses.

Animals↗

PubMed1999

Pathologic changes in the lumbosacral vertebrae and pelvis in Thoroughbred racehorses.

OBJECTIVE: To describe the prevalence, characteristics, and severity of soft-tissue and osseous lesions in the caudal portion of the thoracic and lumbosacral vertebral column and pelvis in Thoroughbred racehorses. ANIMALS: 36 Thoroughbred racehorses that died or were euthanatized at California racetracks between October 1993 and July 1994. PROCEDURE: Lumbosacral and pelvic specimens were collected and visually examined for soft-tissue and osseous lesions. RESULTS: Acute sacroiliac joint injury was observed in 2 specimens. Signs of chronic laxity or subluxation of the sacroiliac joint were not observed in any specimens. Impingement of the dorsal spinous processes and transverse processes was observed in 92 and 97% of specimens, respectively. Thoracolumbar articular processes had variable degrees of degenerative change in 97% of specimens. Degenerative changes were observed at lumbar intertransverse joints and sacroiliac articulations in all specimens. Some degenerative changes were widespread and severe. CONCLUSIONS: Numerous degenerative changes affected vertebral processes, intervertebral articulations, and sacroiliac joints in these Thoroughbred racehorses. CLINICAL RELEVANCE: Various types of vertebral and pelvic lesions need to be considered during clinical evaluation of the back and pelvis in horses. Undiagnosed vertebral or pelvic lesions could be an important contributor to poor performance and lameness in athletic horses.

Animals↗

PubMed1998

Stress fractures of the vertebral lamina and pelvis in Thoroughbred racehorses.

Thirty-six Thoroughbred racehorses that died at California racetracks between October 1993 and July 1994 were evaluated for stress fractures in the caudal portion of the thoracic and lumbosacral regions of the spine and the pelvis. The lumbosacral spine and pelvis were collected, debrided of soft tissues and examined visually for the presence of an incomplete fracture line and focal periosteal proliferation, characteristic of a stress fracture. Sixty-one per cent of specimens had evidence of stress fracture in the caudal portion of the thoracic and lumbosacral regions of the spine and the pelvis. Vertebral lamina stress fractures were found in 50% of specimens and were positively associated with the severity of dorsal spinous process impingement and overall severity of articular process degenerative changes. Pelvic stress fractures affected 28 % of specimens and occurred more frequently in older horses. Pelvic stress fractures were positively associated with the severity of lumbar transverse process impingement and several ilial articular surface degenerative changes. A high prevalence of vertebral and pelvic stress fractures was noted in this sample of Thoroughbred racehorses that died because of unrelated injuries. Vertebral and pelvic stress fractures need to be considered in the clinical evaluation of horses with back problems or hindlimb lameness. Undiagnosed stress fractures of the vertebrae or pelvis could be a significant cause of poor performance and lameness in Thoroughbred racehorses.

Age Factors↗

PubMed1997

Developmental variation in lumbosacropelvic anatomy of thoroughbred racehorses.

OBJECTIVE: To describe the incidence and types of gross osseous developmental variations and ages of physeal closure in the caudal portion of the thoracic and lumbosacral spine and the pelvis in a sample of Thoroughbred racehorses. ANIMALS: Thoroughbred racehorses (n = 36) that died or were euthanatized at California racetracks between October 1993 and July 1994. PROCEDURE: Lumbosacropelvic specimens were collected, and all soft tissues were removed. The osseous specimens were visually examined. RESULTS: Only 22 (61%) specimens had the expected number of 6 lumbar and 5 sacral vertebrae. Eight (22%) specimens had thoracolumbar transitional vertebrae, and 13 (36%) had sacrocaudal transitional vertebrae. Articular process asymmetries were present at 1 or more vertebral segments in 30 (83%) specimens. Intertransverse joints (2 to 4 pairs/specimen) were bilaterally distributed in the caudal portion of the lumbar spine and the lumbosacral joint in 31 (86%) specimens. Five (14%) specimens had asymmetric distribution of the intertransverse joints. Intertransverse joint ankylosis was found in 10 (28%) specimens. Lumbosacral vertebral body physeal closure occurred between 4.9 and 6.7 years of age; pelvic physeal closure occurred between 5.2 and 5.8 years of age. Iliac crest and ischial arch epiphyseal formation was evaluated, using a grading system, and fusion to the underlying bone occurred at 7.2 years and 5.4 years of age, respectively. CONCLUSIONS: Numerous vertebral anatomic variations were commonly found in a sample of Thoroughbred racehorses. CLINICAL RELEVANCE: Normal anatomic variations and ages of skeletal maturity need to be considered in clinical evaluation of the equine spine and pelvis for differentiation from pathologic findings.

Aging↗