Biomedical subjects

K K Haussler

Publications and source records attributed to K K Haussler.

7 recordsLinked to original sources

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↗