Pressure algometry to quantify muscle pain in racehorses with suspected sacroiliac dysfunction

REASONS FOR PERFORMING STUDY: Despite the prevalence of orthopaedic injuries to horses, there is no objective means of quantifying the intensity of musculoskeletal pain. HYPOTHESES: Mechanical nociceptive thresholds (MNT) can be measured repeatably by pressure algometry in horses and MNTs are correlated with both severity of clinical signs and subjective scores of muscle pain on palpation in horses with suspected sacroiliac dysfunction (SID). METHODS: The technique of pressure algometry and its repeatability was tested at 4 anatomical sites on either side of the thoracolumbar and pelvic region in 12 Thoroughbreds in training. In a second series of 15 racing Thoroughbreds, using a different set of landmarks, pain on palpation was assessed by pressure algometry. Horses were grouped based on clinical scores of SID as normal (n = 5), mild (n = 5), moderate (n = 4) and severe (n = 1) suspected SID and scored for muscle pain response by manual palpation. RESULTS: Pressure algometry was shown to be a repeatable measure of MNTs. Horses with suspected SID had significantly lower mean MNT when sites and horses were pooled and showed greater differences in mean algometer measurements between left and right sides, compared to control horses. A significant correlation was found between mean pressure algometry measurements and both suspected SID grade and muscle pain response on palpation. CONCLUSION AND POTENTIAL RELEVANCE: Horses with suspected SID displayed lower MNTs compared to control horses, especially in the pelvic region. This supports a potential role for pressure algometry in providing an objective means of quantifying musculoskeletal pain reflected as a reduced MNT associated with SID and its response to physiotherapy or other treatments.     

The effects of chiropractic, massage and phenylbutazone on spinal mechanical nociceptive thresholds in horses without clinical signs

REASON FOR PERFORMING STUDY: Common methods used to treat back problems in horses need to be assessed objectively. OBJECTIVES: To measure spinal mechanical nociceptive thresholds (MNTs) and evaluate the effects of chiropractic, massage and phenylbutazone, compared with active and inactive control groups. METHODS: Baseline MNTs at 7 sites within the thoracolumbar and sacral regions were measured in 38 healthy mature horses exhibiting no clinical signs of lumbar pain. Horses were assigned to one of 3 treatment groups: instrument-assisted chiropractic treatment, therapeutic massage and phenylbutazone; or 2 control groups: ridden exercise (active control) or routine paddock turnout with no ridden exercise (inactive control). MNT measurements were repeated at 1, 3 and 7 days post treatment. The percentage change from baseline MNT values was calculated within groups. RESULTS: On Day 7, the median MNT had increased by 27, 12 and 8% in the chiropractic, massage and phenylbutazone groups, respectively. MNT changes of <1% were seen within the active and inactive control groups. CONCLUSIONS: Chiropractic treatment and massage therapy increased spinal MNTs within horses not exhibiting signs of lumbar pain. POTENTIAL RELEVANCE: Pressure algometry provides an objective tool to evaluate the effects of commonly used, but currently unproven treatment modalities on spinal MNTs. Future studies need to evaluate combined treatment effects and longer-term MNT changes in horses with documented back pain.     

The Effect of Pulsed Electromagnetic Fields on Back Pain in Polo Ponies Evaluated by Pressure Algometry and Flexion Testing—A Randomized,Double-blind,Placebo-controlled Trial

This study assessed the therapeutic effect of pulsed electromagnetic fields (PEMF) on the backs of Polo ponies by measuring mechanical nociceptive thresholds (MNTs) and induced back movement. Twenty Polo ponies in regular training and competition were assigned to two groups. A double-blind, placebo-controlled, crossover field study with PEMF was performed, consisting of two 10-day therapy periods. At the beginning and end of each therapy period, the MNTs from 25 sites of the horses backs were assessed by pressure algometry (PA), and induced back movement was evaluated by flexion testing. Baseline MNTs were generally low, with means between 6.4 and 10.0 kg/cm². Significant changes in MNTs occurred nearly equally after both the PEMF and the placebo control treatments (at 5 of 25 or 6 of 25 sites, respectively) and without any regular pattern. Changes were evident, predominantly as decreased MNTs within and between treatment periods. Flexion testing revealed stiffness or avoidance in 19 of 20 horses. Results of the flexion testing showed an increased number of physiologic reactions at the end of both treatment periods compared with baseline values. The effect of PEMF on back pain and range of induced back movement could not be proven in this study. Although pretherapy values indicated the horses might have experienced back pain, all horses were still actively used in sport, and back pain might not have been severe enough to allow a significant effect to be demonstrated.     

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.     

The lumbosacral junction in working german shepherd dogs -- neurological and radiological evaluation

The clinical and radiological incidence of lumbosacral (LS) disease was studied on 57 German Shepherd dogs (GSDs) used in active service. The study included a clinical history, a neurological examination, and plain radiographs of the caudal lumbar vertebrae. The neurological examinations revealed lower back pain and/or neural deficits in 21 dogs, of which 14 had a history of pain or pelvic gait abnormalities. Radiographic findings were spondylosis at L7-S1, degeneration of L7-S1 disc, LS malalignment, transitional LS vertebrae and/or primary spinal canal stenosis in 15 dogs with neurological abnormalities and/or back pain and in 18 dogs with no clinical signs. No correlation between the neurological and the radiographic findings were found. This study demonstrates that even prominent radiographic LS abnormalities are of minimal value in the evaluation of LS disease in the GSD.     

RADIOGRAPHIC APPEARANCE OF EQUINE LUMBOSACRAL AND PELVIC ABNORMALITIES BY LINEAR TOMOGRAPHY

Radiologic findings are described in 20 horses with clinical signs of a caudal lumbar or hindlimb problem; the horses were subjected to linear tomography of the lumbosacral and pelvic regions. The cases could be divided into four groups: sacroiliac arthrosis (6 horses), lumbosacral abnormalities (3 horses), pelvic or lumbar fracture (6 horses), and no radiographic abnormalities (5 horses). Five of the six horses with sacroiliac arthrosis had spur formation, with localized arthrosis at the caudal aspect of the sacral wing and its articulation with the auricular surface of the ilium. In one horse these lesions were confirmed at postmortem examination. The sixth horse, a Standardbred trotter, had more even and widespread arthrosis of the sacroiliac joint. The three lumbosacral abnormalities were present in two horses with fusion of the L₅-L₆ articulation and one horse with a wider than normal sacrolumbar articulation. Linear tomography also proved to be of diagnostic and prognostic value in the evaluation of lumbar and pelvic fractures. Finally, tomography could be used to eliminate the presence of sacroiliac or lumbosacral damage in some horses that presented with clinical signs suggestive of disease of the lumbosacral or sacroiliac region.     

Mechanical nociceptive thresholds within the pastern region of Tennessee Walking Horses

REASONS FOR PERFORMING STUDY: 'Soring' is the term used to describe the application of an irritant to the distal forelimbs of gaited horses with the sole intent of inflicting pain and inducing altered gait, illegally practiced in Tennessee Walking Horses. Objective methods for the detection of limb pain due to this practice are, however, lacking. OBJECTIVES: To assess whether Tennessee Walking Horses respond to manual pressures相似文献   

Kinematic evaluation of the back in the sport horse with back pain

REASONS FOR PERFORMING STUDY: Earlier studies have developed a clinical tool to evaluate objectively the function of the equine back. The ability to differentiate horses with back pain from asymptomatic, fully functioning horses using kinematic measures from this tool has not been evaluated. OBJECTIVES: To compare the kinematics of the back at walk and trot in riding horses with back dysfunction to the same parameters in asymptomatic sport horses. METHODS: The kinematics of the back in 12 horses with impaired performance and back pain were studied at walk and trot on a treadmill. Data were captured for 10 sees at 240 Hz. Range of movement (ROM) and intravertebral pattern symmetry of movement for flexion and extension (FE), lateral bending (LB) and axial rotation (AR) were derived from angular motion pattern data and the results compared to an earlier established database on asymptomatic riding horses. RESULTS: At walk, horses with back dysfunction had a ROM smaller for dorsoventral FE in the caudal thoracic region (T13 = 7.50 degrees, T17 = 7.71 degrees; P<0.05), greater for LB at T13 (8.13 degrees; P<0.001) and smaller for AR of the pelvis (10.97 degrees; P<0.05) compared to asymptomatic horses (FE-T13 = 8.28 degrees, FE-T17 = 8.49 degrees, LB-T13 = 6.34 degrees, AR-pelvis = 12.77 degrees). At trot, dysfunctional horses had a smaller (P<0.05) ROM for FE at the thoracic lumbar junction (T17 = 2.46 degrees, L1 = 2.60 degrees) compared to asymptomatic horses (FE-T17 = 3.07 degrees, FE-L1 = 3.12 degrees). CONCLUSIONS: The objective measurement technique can detect differences between back kinematics in riding horses with signs of back dysfunction and asymptomatic horses. The clinical manifestation of back pain results in diminished flexion/extension movement at or near the thoracic lumbar junction. However, before applying the method more extensively in practice it is necessary to evaluate it further, including measurements of patients whose diagnoses can be confirmed and long-term follow-ups of back patients after treatment. POTENTIAL RELEVANCE: Since the objective measurement technique can detect small movement differences in back kinematics, it should help to clinically describe and, importantly, objectively detect horses with back pain and dysfunction.     

Effects of Large Saddle Panels on the Biomechanics of the Equine Back During Rising Trot: Preliminary Results

The saddle panels, directly in contact with the horse's back, are likely an important element to optimize the fitting of the saddle, the comfort of the horse, and subsequently, the pain management in dorsalgic horses. The aim of this study was to better understand the effect of the saddle panels on the horse's back, by evaluating a prototype saddle (comfort panels: CP) compared to a standard saddle (STD). The horse's back movements were measured using inertial measurement units (IMUs) fixed at the levels of thoracic vertebrae T6, T12, T16 (under the saddle) and lumbar vertebrae L2 and L5. The centers of mass (COMs) of the horse and the rider and limb's protraction-retraction angles, pressure between saddle and horse's back, and force on the stirrups were measured using respectively 2D motion capture, pressure mat and force sensors in the stirrup leather. Three horses were trotted at the rising trot (sitting: left diagonal-rider seated; standing: right diagonal-rider standing) by the same rider. To compare saddles, linear mixed-effects regression models were used. The estimated means (SE) were calculated. During sitting phase, pressure in the cranial and middle areas of the saddle significantly increased for CP compared to STD (+0.9 (0.2) kPa and +1.0 (0.1) kPa, respectively) whereas caudal pressure decreased (−1.8 (0.4) kPa). Concurrently, the range of motion of angles T12-T16 and T16-L2 under the saddle significantly increased (+1.8 (0.2)° and +2.3 (0.3)°, respectively). The results showed that modifications of the panels' shape not only affect the pressure distribution but also the kinematics of the thoracic and lumbar regions of the equine back.     

ULTRASONOGRAPHIC FINDINGS IN THE LUMBOSACRAL JOINT OF 43 HORSES WITH NO CLINICAL SIGNS OF BACK PAIN OR HINDLIMB LAMENESS

The transrectal ultrasonographic appearance of the lumbosacral joint was assessed in 43 horses with no history or clinical evidence of back pain or hindlimb lameness. In the majority of horses (34/43, 79.1%) the lumbosacral disc had uniform or mildly heterogeneous echogenicity. However, variation in the ultrasonographic appearance of the lumbosacral joint was also identified, including hyperechogenic regions within the lumbosacral disc with or without an acoustic shadow, and mild or moderate irregularity of the opposing surfaces of the last lumbar and the first sacral vertebral bodies. Marked irregularity of the bony surfaces or marked disruption of the lumbosacral disc was not seen in any horse. The mean distance between the ventral aspects of the last lumbar and first sacral vertebrae was 14.2 mm (range: 7.1–26.5 mm, median: 14.4 mm). The degree of protrusion of the ventral aspect of the lumbosacral disc ranged from 0 to 5 mm (mean: 1.32 mm, median: 1.2 mm). The mean angle between the ventral surfaces of the last lumbar and first sacral vertebrae was 147° (range: 118–165°, median: 150°). There was no significant effect of age, breed, gender, or the size of the horses on either subjective findings in the lumbosacral joint or objective measurements.     

Clinical progress in the diagnosis of thoracolumbar problems in horses

It is well known that a painful back can be responsible for loss of performance in horses. Veterinary examination of the sore back used to be limited to manual palpation with diagnosis confirmed empirically by response to treatment. Today, due to advances in imaging, there are multiple methods for evaluating the pathology of the horse's thoracolumbar (TL) spine. Radiography, ultrasonography, nuclear scintigraphy, thermography and algometry all play a part in developing a better understanding of equine TL problems. Despite this progress, definitive diagnosis can still be problematic. There is a lack of objectivity in understanding the implications of the pathology detected and its effect on the horse. It is difficult to determine the degree of pain experienced by individual horses and how that interferes with their performance and welfare. This paper emphasises the importance of a systematic clinical examination to identify the presence of pain that can be supported by recognition of pathology using a range of diagnostic aids. These will also be reviewed to assist the clinician in understanding the tools available to evaluate a horse with a sore back.     

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.     

Effects of vertebral mobilization and manipulation on kinematics of the thoracolumbar region

OBJECTIVE: To measure passive spinal movements induced during dorsoventral mobilization and evaluate effects of induced pain and spinal manipulative therapy (SMT) on passive vertebral mobility in standing horses. ANIMALS: 10 healthy adult horses. PROCEDURES: Baseline vertical displacements, applied force, stiffness, and frequency of the oscillations were measured during dorsoventral spinal mobilization at 5 thoracolumbar intervertebral sites. As a model for back pain, fixation pins were temporarily implanted into the dorsal spinous processes of adjacent vertebrae at 2 of the intervertebral sites. Vertebral variables were recorded again after pin placement and treadmill locomotion. In a randomized crossover study, horses were allocated to control and treatment interventions, separated by a 7-day washout period.The SMT consisted of high-velocity, low-amplitude thrusts applied to the 3 non-pin-placement sites. Control horses received no treatment. RESULTS: The amplitudes of vertical displacement increased from cranial to caudal in the thoracolumbar portion of the vertebral column. Pin implantation caused no immediate changes at adjacent intervertebral sites, but treadmill exercise caused reductions in most variables. The SMT induced a 15% increase in displacement and a 20% increase in applied force, compared with control measurements. CONCLUSIONS AND CLINICAL RELEVANCE: The passive vertical mobility of the trunk varied from cranial to caudal. At most sites, SMT increased the amplitudes of dorsoventral displacement and applied force, indicative of increased vertebral flexibility and increased tolerance to pressure in the thoracolumbar portion of the vertebral column.     

Nuclear scintigraphic assessment of the thoracolumbar synovial intervertebral articulations

Reasons for performing study: The results of nuclear scintigraphic examination of the thoracolumbar synovial intervertebral articulations (facet joints) have to date been poorly documented. Objectives: To establish an objective scintigraphic grading system for the facet joints; to investigate the relationship between the presence or absence of clinical signs of back pain and increased radiopharmaceutical uptake (IRU); and to compare the results of scintigraphy and radiography. Methods: Nuclear scintigraphic images of the 13th thoracic (T13) to first lumbar (L1) vertebrae were graded subjectively (visual assessment of the image) and objectively (using region of interest analysis) from 31 clinically normal horses in full work (Group N) and 65 horses with clinical evidence of thoracolumbar region pain and osteoarthritis of ≥1 facet joint (Group B). Sensitivity and specificity of IRU for detection of back pain and radiographic abnormalities were assessed. A Spearman correlation was performed to test for an association between the grade of IRU and the classification of radiographic abnormality. Results: The objective scintigraphic grades were matched by 96.7% of subjective grades. IRU was seen more commonly in Group B (61.5%) than in Group N (25.8%), and moderate or intense IRU was only seen in Group B. The strongest association between radiographic abnormalities and scintigraphy was seen in horses with intense IRU. Conclusions: Moderate or intense IRU in a facet joint is more likely to be seen in horses with back pain than in clinically normal horses. Potential relevance: Nuclear scintigraphy is a potentially useful tool in the evaluation of a horse with thoracolumbar region pain.     

Review of the use of transrectal ultrasonography for evaluation of the caudal lumbar – including lumbosacral – intervertebral discs and symphyses: Normal and abnormal ultrasonographic appearance

Transrectal ultrasonography of the lumbosacroiliac area is routinely performed for the diagnosis of the cause of low back pain and poor hindlimb impulsion and engagement. The ventral aspect of the caudal lumbar intervertebral discs and vertebrae can be easily assessed transrectally with ultrasound while other imaging modalities have limitations for diagnosis of intervertebral disc injuries. This paper is a review of the ultrasonographic procedure for imaging the ventral aspect of the caudal lumbar and lumbosacral symphyses, especially the intervertebral discs. Normal images, findings and lesions of the three caudalmost lumbar intervertebral discs are described (between the 4th lumbar and the 1st sacral vertebrae).     

蒙古羊不同尾椎数相关选择信号的挖掘研究

通过对比不同尾椎数的蒙古绵羊群体在基因组上的遗传分化水平,对全基因组选择信号、蒙古羊尾长性状的相关基因及可能的突变位点进行检测,试图解析尾椎形成的分子机制。基于全基因组重测序数据,使用两组群间的遗传分化系数(Fst)和遗传多样性比率(pi ratio)检测尾椎选择信号,将Fst值和pi ratio较大的染色体区段作为受选择候选区域。结果表明,共找到76个选择区域,这些区域分别落在了尾脂肪沉积和骨骼发育的QTL上,进一步对这些候选区域所包含的63个基因进行基因功能及通路的注释分析,富集到骨骼再生相关的Wnt和FGF信号通路,同时发现LRP6等功能候选基因。该研究确定了与尾椎数相关的受选择区域,推测不同尾椎数蒙古绵羊群体的形成可能由非基因编码区域的一个或者多个突变造成。     

EX VIVO COMPUTED TOMOGRAPHIC EVALUATION OF MORPHOLOGY VARIATIONS IN EQUINE CERVICAL VERTEBRAE

Diagnostic imaging is one of the pillars in the clinical workup of horses with clinical signs of cervical spinal disease. An improved awareness of morphologic variations in equine cervical vertebrae would be helpful for interpreting findings. The aim of this anatomic study was to describe CT variations in left–right symmetry and morphology of the cervical and cervicothoracic vertebrae in a sample of horses. Postmortem CT examinations of the cervical spine for horses without congenital growth disorders were prospectively and retrospectively recruited. A total of 78 horses (27 foals, 51 mature horses) were evaluated. Twenty‐six horses (33.3%) had homologous changes in which a transposition of the caudal part of the transverse process (caudal ventral tubercle) of C6 toward the ventral aspect of the transverse process of C7 was present (n = 10 bilateral, n = 12 unilateral left‐sided, n = 4 unilateral right‐sided). There was one horse with occipito‐atlantal malformation, two horses with rudimentary first ribs bilaterally, and one horse with bilateral transverse processes at Th1, representing homeotic (transitional) vertebral changes. Chi‐square tests identified no significant differences in the number of conformational variations between the group of mature horses with or without clinical signs (P = 0.81) or between the group of mature horses and the group of foals (P = 0.72). Findings indicated that, in this sample of horses, the most frequently identified variations were homologous variations (transposition of the caudal part of the transverse process of C6–C7) in the caudal equine cervical vertebral column. Homeotic (transitional) variations at the cervicothoracic vertebral column were less common.     

Effect of local analgesia on movement of the equine back

REASONS FOR PERFORMING STUDY: Diagnostic infiltration of local anaesthetic solution is commonly used in cases of equine back pain. Evaluation is subjective and it is not known how local analgesia of the back affects horses without clinical signs of back pain. OBJECTIVES: To evaluate the effect of infiltration of local anaesthetics on the movement of the back in horses without clinical signs of back pain, and to evaluate the usefulness of kinematic studies as an objective and quantitative tool in evaluating local analgesia in clinical practice. METHODS: The kinematics of the back in 10 clinically sound horses were measured on 2 occasions at walk and trot before and after injections with mepivacaine and sodium chloride around the interspinous spaces between T16 and L2. The kinematics were compared between the 2 occasions before injections and before and after each injection. RESULTS: The range of motion (ROM) for dorsoventral flexion-extension (FE) of the back was increased significantly in all measured segments other than T10 at walk, as was lateral bending (LB) at T10, L3 and L5 after injection of mepivacaine. For lateral excursion (LE), total movement increased at all measured segments. At trot the only affected segment was L3, where the injection with mepivacaine decreased the ROM for FE. After injection of sodium chloride the ROM for FE increased at T13 and T17 at walk. Lateral bending and LE were not affected at walk. At trot, LB increased at L3 and L5. CONCLUSIONS AND POTENTIAL RELEVANCE: Diagnostic infiltration of local anaesthetic solution affects the function of the back in clinically sound horses, which must be considered when interpreting the use of this clinical aid in assessing clinical cases of back dysfunction. Kinematics can qualitatively and quantitatively evaluate the effect of local analgesia of the back.     

Surgical treatment of lumbosacral discospondylitis by a distraction-fusion technique

Lumbosacral discospondylitis was diagnosed in three adult dogs by radiography and the isolation of Staphylococcus aureus from the affected intervertebral space. The predominant clinical findings of severe spinal pain and marked hindlimb lameness suggested entrapment of the seventh lumbar spinal nerve roots. In addition, the presence of hindlimb ataxia, proprioceptive deficits, perineal analgesia and paresis of the tail were consistent with compression of the cauda equina. Despite medical therapy with analgesics, antibiotics and strict confinement the clinical and radiographic signs progressed. A lumbosacral distraction-fusion procedure was employed to decompress the spinal nerve roots and cauda equina and to stabilise the affected vertebrae. In all cases there was an immediate marked reduction in spinal pain and a long term resolution of clinical signs. In two cases the affected vertebrae progressively fused within four months. The third case required removal of the implants due to pin migration and breakage.     

Surgical decompression of a caudal vertebral disc extrusion by dorsal laminectomy

A 3.5-year-old female spayed Beagle cross was presented to our emergency and referral facility for the complaint of acute onset paralysis of the tail. A full physical and neurological examination was performed which confirmed the absence of motor function in the tail. Signs of superficial and deep pain sensation to the tail remained intact. Orthogonal view survey radiographs identified mineralization superimposed over the intervertebral foramen of the first and second caudal vertebrae. A dorsal laminectomy was performed for surgical decompression of the caudal nerve roots. On the fourth postoperative day, the patient exhibited good motor function of the tail. Neurological improvement continued and 11 days postoperatively the patient demonstrated normal neurological function, free range-of-motion of the tail, and it did not exhibit any signs of pain. Follow-up examination was performed 76 days after surgery, at which time the patient exhibited normal neurological function and signs of a pain-free range-of-motion on manipulation of its tail.