Abstract
A shoe was designed to combine the advantages of a reverse shoe and an adjustable heart bar shoe in the treatment of chronic laminitis. This reverse even frog pressure (REFP) shoe applies pressure uniformly over a large area of the frog solar surface. Pressure is applied vertically upward parallel to the solar surface of the frog and can be increased or decreased as required. Five clinically healthy horses were humanely euthanased and their dismembered forelimbs used in an in vitro study. Frog pressure was measured by strain gauges applied to the ground surface of the carrying tab portion of the shoe. A linear variable distance transducer (LVDT) was inserted into a hole drilled in the dorsal hoof wall. The LVDT measured movement of the third phalanx (P3) in a dorsopalmar plane relative to the dorsal hoof wall. The vertical component of hoof wall compression was measured by means of unidirectional strain gauges attached to the toe, quarter and heel of the medial hoof wall of each specimen. The entire limb was mounted vertically in a tensile testing machine and submitted to vertical downward compressive forces of 0 to 2,500 N at a rate of 5 cm/minute. The effects of increasing frog pressure on hoof wall weight-bearing and third phalanx movement within the hoof were determined. Each specimen was tested with the shoe under the following conditions: zero frog pressure; frog pressure used to treat clinical cases of chronic laminitis (7 N-cm); frog pressure clinically painful to the horse as determined prior to euthanasia; frog pressure just alleviating this pain. The specimens were also tested after shoe removal. Total weight-bearing on the hoof wall at zero frog pressure was used as the basis for comparison. Pain-causing and pain-alleviating frog pressures decreased total weight-bearing on the hoof wall (P < 0.05). Frog pressure of 7 N-cm had no statistically significant effect on hoof wall weight-bearing although there was a trend for it to decrease as load increased. Before loading, the pain-causing and pain-alleviating frog pressures resulted in a palmar movement of P3 relative to the dorsal hoof wall compared to the position of P3 at zero frog pressure (P < 0.05). This difference remained statistically significant up to 1300 N load. At higher loads, the position of P3 did not differ significantly for the different frog pressures applied. It is concluded that increased frogpressure using the REFP shoe decreases total hoof wall weight-bearing and causes palmar movement of P3 at low weight-bearing loads. Without a shoe the toe and quarter hoof wall compression remained more constant and less in magnitude, than with a shoe.
Highlights
Equine laminitis is a serious condition that usually ends the animal’s athletic career and often necessitates euthanasia.aDepartment of Companion Animal Clinical Studies, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort, 0110 South Africa. bLaboratory for Advanced Engineering, PO Box 30536, Sunnyside, Pretoria, 0132 South Africa. c Witbos Veterinary Clinic, PO Box 30740, Kyalami, 1684 South Africa. dDepartment of Information Technology, Division of Academic Computing, University of Pretoria, Pretoria, 0001 South Africa. eDepartment of Statistics, University of Pretoria, Pretoria, 0001 South Africa.Received: August 1998
The percentage force carried by the hoof wall with treatment frog plate absent (FA) was approximately 100 %
As load increased for torque setting (TS), T1 and T2, relatively more weight was carried by the hoof wall
Summary
Equine laminitis is a serious condition that usually ends the animal’s athletic career and often necessitates euthanasia.aDepartment of Companion Animal Clinical Studies, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort, 0110 South Africa. bLaboratory for Advanced Engineering, PO Box 30536, Sunnyside, Pretoria, 0132 South Africa. c Witbos Veterinary Clinic, PO Box 30740, Kyalami, 1684 South Africa. dDepartment of Information Technology, Division of Academic Computing, University of Pretoria, Pretoria, 0001 South Africa. eDepartment of Statistics, University of Pretoria, Pretoria, 0001 South Africa.Received: August 1998. In a horse with chronic laminitis, P3 may move relative to the hoof wall, either rotating palmarly (capsular or phalangeal rotation) or moving vertically distally (sinker, founder)[19,22]. This movement of P3 may have prognostic significance. The results of another study indicated that a functional athletic outcome of horses did not correlate with the degree of P3 rotation, but that ‘clinical assessment (of the horse with chronic laminitis) is a more reliable means of determining the final outcome and should be given precedence over radiographic findings’[26]. Distal displacement of P3 has a poor prognosis[2,9,26]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Journal of the South African Veterinary Association
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
