Relationship between spinal biomechanics and pathological changes in the equine thoracolumbar spine

Abstract

Summary The relationship between spinal biomechanics and pathological changes occurring in functionally normal equine thoracolumbar spines was studied in 23 horses. Ventrolateral vertebral body osteophytes occurred in 36 per cent of the spines. The majority occurred between the 10th and 17th thoracic vertebrae with the largest being found between the 11th and 13th thoracic vertebrae, the region of the thoracic spine where the greatest amount of lateral bending and axial rotation occurs. Impingement of the dorsal spinous processes was detected in 86 per cent of the spines with most lesions occurring between the 13th and 18th thoracic vertebrae. The severity of occurrence of impingement did not appear to be related to regional spinal mobility. Degeneration of intervertebral discs was observed in three of four specimens that were sectioned sagittally. It occurred in the first thoracic and the lumbosacral intervertebral discs and appeared to be related to the increased dorsoventral mobility and the increased disc thickness of these joints. The characteristic distribution of fractures of the thoracolumbar spine is discussed with respect to the biomechanics of the spine.

The radiographic frequency of impingement of the dorsal spinous processes at purchase examination and its clinical significance in 220 warmblood sporthorses

“…A high prevalence of DSP impingement has been reported in several earlier studies in which a wide variety of abnormal findings of the DSPs was found on radiographic and scintigraphic examinations (Jeffcott 1979, Erichsen 2004, Holmer 2007. In a post-mortem study with 23 functionally normal horses 83 % had impingement of the dorsal spinous processes (Townsend 1986). Another study including 36 racehorses killed on the track, showed that 92 % had impingement of the dorsal spinous processes (Haussler 1999).…”

“…Impingement of dorsal spinous processes is commonly identified radiologically in horses showing no clinical evidence of pathology (Crowhurst 1975, Jeffcott 1979, Geiger 2015; 37 % of 110 horses had radiographic evidence of overriding spinous processes without clinical signs of back pain. Impinging or overriding dorsal spinous processes were found post mortem in between 83 % (of 23 horses) and 96 % (of 36 horses) showing no clinical evidence of disease or pain (Townsend 1986, Haussler 1999. Impingement of spinous processes has also been recognized in man as Baastrup disease or kissing spines syndrome.…”

Diagnostic procedure for the verification of an assumed backproblem in the horse

“…Wesentlich höher fällt der Prozentsatz bei Untersuchungen an sezierten Tieren aus. Townsend et al (1986) geben die Häufigkeit des KSS an 23 mazerierten, routinemäßig sezierten Wirbelsäulen mit 86% an. Aufgrund des hohen Prozentsatzes des an mazerierten Wirbelsäulen gefundenen KSS fordert Townsend (1985), das KSS klinisch nicht relevant anzusehen, bis eindeutige Schmerzsymptome auftreten.…”

“…Townsend et al (1986) geben die Häufigkeit des KSS an 23 mazerierten, routinemäßig sezierten Wirbelsäulen mit 86% an. Aufgrund des hohen Prozentsatzes des an mazerierten Wirbelsäulen gefundenen KSS fordert Townsend (1985), das KSS klinisch nicht relevant anzusehen, bis eindeutige Schmerzsymptome auftreten. Eine Diskrepanz besteht also zwischen röntgenologischen Befunden und klinischer Symptomatik, wie die Untersuchungen von Jeffcott (1979aJeffcott ( , 1980, Petterson et al (1987) und Kreling (1995 er und Gundel 1996;Denoix 1996).…”

Postural changes and their effects in elite riders when actively influencing the horse versus sitting passively at trot

“…During ridden exercise, the rider's weight applies substantial forces to the horse's back (Fruehwirth et al, 2004) that play a role in the aetiology of equine back pain (Von Peinen et al, 2010), which is common in athletic horses (Haussler, 1999;Jeffcott, 1980;Townsend et al, 1986). Sport horse veterinarians are increasingly called upon to evaluate horses under saddle and to pass judgement on saddle fit and rider effects.…”