The accuracy of the patellar reflex for localization of the site of a single level thoracolumbar disc herniation in dogs

Abstract

The patellar reflex was used in this study to determine the site of thoracolumbar spinal cord dysfunction (T3-L3 or L4-L6) as a result of disc herniation. The results of neurological examinations were compared with the findings of CT myelography. This study was conducted on 21 dogs, selected from a total of 26 dogs confirmed to have a single thoracolumbar lesion. Results revealed that the accuracy of the patellar reflex for lesion localization was 71.4%. The accuracy of the patellar reflex (normal or hyperreflexic) for lesion localization in the T3-L3 segment in 15 dogs was 100%, while the accuracy of the depressed patellar reflex for lesion localization in the L4-L6 segment in 6 dogs was 0%. The accuracy of the patellar reflex for detection of laterality of a thoracolumbar lesion was low (33.33%). The results suggest that the patellar reflex was not reliable for neurolocalization of thoracolumbar spinal cord lesions in dogs. This could be related to the fact that the depressed reflex did not always refer to a lesion in the L4-L6 spinal cord segment. Moreover, the patellar reflex was not reliable in detecting the laterality of thoracolumbar lesions.

Comparison of interobserver agreement between the evaluation of bicipital and the patellar tendon reflex in healthy dogs

“…In contrast to the work of Abdelhakiem et al [18] and Forterre et al [20], the patients in our study were all healthy and thus represented a homogenous group with high prevalence of the category 'normal'. Therefore, one could assume that the IA when assessing a reliable reflex should be 100%, however, perfect agreement is highly unlikely in medical studies [14].…”

“…They described the findings in dogs with confirmed lesions within the lower motor neuron reflex arc of the pelvic limb in which only 37.5% showed a reduced withdrawal reflex, and a reduced PTR was found only in 16.7%. Additionally, Abdelhakiem et al [18] found in their study no lower motor neuron lesion to the pelvic limbs in dogs with a reduced reflex-activity (PTR). However, in nearly 30% of cases, a reduced reflex answer was misdiagnosed by the examiner for a lesion within the lower motor neuron of the pelvic limbs.…”

“…Objectification of the neurological examination is a major topic of current veterinary research [15, 18, 20, 45, 46, 51, 52, 55] with increasing recognition of the importance of evaluating the reliability and therefore the utility of different neurological examination parameters. Our results highlight the need to objectively evaluate the neurological examination and to consider the many factors that might influence its assessment and therefore decrease its reliability.…”

“…However, assessment of reflexes in the daily clinical setting can be highly subjective [1, 7, 8] and has the potential to be influenced by various factors including the age of the patient [9–11], the muscle temperature [12, 13], the observer´s level of expertise [7, 14, 15] or the examination itself [16, 17]. Interestingly, different studies have shown that both the degree of reliability and sensitivity are variable [7, 18–22]. Considering the clinical importance of case discussion and communication between different practitioners their clinical examination findings need to be comparable.…”

Papillary meningioma with multifocal leptomeningeal spread in a dog

“…Several studies report on the reliability of the clinical neurological examination with regard to localisation (neurolocalisation). [17][18][19][20][21][22] From those studies, it is clear that the neurolocalisation is not always entirely accurate and that lesions may be clinically 'silent' .…”