Sensory Effects in Man of Lesions of the Posterior Columns and of Some Other Afferent Pathways

Abstract

Clinical observations are presented on the sensory effects of lesions of different afferent pathways of the spinal cord, correlated whenever possible with histological evidence of the location and extent of the lesions. They are based on personal cases and on significant cases in the literature, including posterior column section, other causes of damage to the posterior columns, and cases of commissural myelotomy. It is concluded that the traditional view of the effects of lesions of the posterior columns is correct, but that evidence from cases proved by postmortem examination is still needed. When the information normally supplied by the posterior columns is cut off, primary sensibility for light touch and pressure is not lost, but any kind of discrimination is disturbed. There is also a disturbance in knowledge of movement and position, ataxia, and clumsiness in the use of the hands. These defects greatly affect the palpatory examination of objects and, although they may appear slight on routine neurological examination, they can cause severe disturbances in the activities of daily living. For tactile modalities, a lesion of the spinothalamic complex causes minimal or no defects and a lesion of the posterior columns causes only slight defects, whereas a lesion of both pathways gives rise to total loss of tactile and pressure sensibility in the part of the body served by both pathways. This conclusion is based on 2 cases with combined commissural myelotomy and anterolateral cordotomy. The following disturbances of mechanoreception attributed to lesions of the posterior columns are discussed: lability of threshold, persistence of sensation, tactile and postural hallucinations and temporal and spatial disturbances. In man, lesions of the posterior columns cause an increase in pain, tickle, warmth and cold. Cases are presented with and without lesions of the posterolateral columns in conjunction with lesions of one or both anterolateral columns. As these lesions did not affect sensation and as there was no difference in the sensory state following anterolateral cordotomies with or without involvement of the posterolateral column, it is concluded that lesions of this column have no effect on sensation. Cases with lesions of the anterior two-thirds of the cord are also presented to illustrate the sensory state with only the posterior third of the cord intact. In these cases, tactile and pressure sensibility and knowledge of movement and position are normal.

Lesions Limited to the Human Thalamic Principal Somatosensory Nucleus (Ventral Caudal) Are Associated with Loss of Cold Sensations and Central Pain

“…Previous electrophysiological studies have provided strong evidence that neurons in Vc, the terminus of the dorsal columnmedial lemniscus pathway, mediate the sensations evoked by tactile stimuli (Mountcastle, 1984;Lenz et al, 1988b;Ohara et al, 2004). Finally, all of these results are consistent with studies of spinal cord lesions, which demonstrate that the dorsal columns are essential for normal tactile sensation (Noordenbos and Wall, 1976;Nathan et al, 1986).…”

Loss and spontaneous recovery of forelimb evoked potentials in both the adult rat cuneate nucleus and somatosensory cortex following contusive cervical spinal cord injury

“…Damage to the adult human cervical spinal cord dorsal columns leads to sensory dysfunctions of the upper limbs as evidenced by transient exaggeration or abolishment of the cutaneous sensations of fine touch, vibration, and proprioception (for a review, see York, 1985;Nathan et al, 1986). Similarly (Metz et al, 2000;Norenberg et al, 2004), transient and persistent upper limb cutaneous sensation dysfunctions occur in adult rats with damage to their cervical spinal cord dorsal columns (Schrimsher and Reier, 1993;McKenna and Whishaw, 1999;Ballerman et al, 2001a,b;Onifer et al, 2005;Kanagal and Muir, 2007).…”

Sensation of defecation in patients with spinal cord injury

“…However, the prickling sensation emerges in the paralyzed part of the body, 25 often associated with increased sensibility. 26 No reports could be found about a prickling sensation above the level of SCI.…”