허리디스크로 발생하는 local, referred and radiating의 해부, 생리학적 기초 - 수련의 몫. 반드시 공부해야

[문형철]

허리디스크가 있을때 환자가 호소하는 통증은 그것이 어떤 통증인지 반드시 구분되어야 한다.

1. local low back pain

1) discogenic pain

2) mechanical back pain

3) muscle pain

4) facet joint pain

5) si joint instability

6) ligament pain

2. radiating pain

1) discogenic (intervertebral disc)

2) spondylogenic (spinal bony structures)

3) musculogenic  (intrinsic spinal and external perispinal muscles)

4) ligamentogenic (intrinsic spinal ligaments) normal sensation and pathologic pain

5)articulogenic (posterior spinal facet joints)

더 세밀하게 구분하려면 무엇을 더 알아야 할까? 그것에 대한 답을 제시하는 논문

허리디스크로 발생하는 local, referred and radiati.pdf

INTRODUCTION

The clinical state accompanying nonspecific injury to the spinal column and perispinal soft tissues may be manifest in a complex combination of somatic and autonomic syndromes. The overall combined symptom complex includes: 

1) local somatic spinal pain

2) radiating radicular pain

3) radiating/radicular paresthesias

4) radiating/referred skeletal muscle spasm/dysfunction

5) radiating/referred autonomic dysfunction

6) referred pain

7) referred generalized alterations in viscerosomatic tone. 

In practice these clinical manifestations are typically superimposed upon one another and are of varying individual expression‎. The anatomic basis for the origin and mediation of clinical signs and symptoms originating within the lumbosacral spine is related to direct spinal innervation, the spinal nerve roots and nerves, and the lumbosacral sympathetic plexus. 

Specifically, the relevant neural structures include: afferent and efferent somatic neural branches emanating from the ventral and dorsal rami of the lumbosacral spinal nerves, neural branches projecting to and originating from the paravertebral autonomic (sympathetic) neural plexus and the spinal nerves/lumbosacral plexi themselves.

Neural fibers from these structures originate and terminate in the spinal column and related non neural tissues (e.g., bone, periosteum, meninges, spinal ligaments, perispinal musculature, spinal column and perispinal blood vessels) in the spinal neural tissue itself (e.g., spinal rami, nerves), and in the distant peripheral tissues within the somatic and visceral distribution of these nerves (e.g., spinal column, perispinal soft tissues, buttocks, lower extremities, pelvis). 

Finally, the intimate connections of these neural structures with the central nervous system, including the spinal cord and the higher cortical and noncortical centers of the cerebrum, are ultimately responsible for the manifestations of clinical syndromes in the patient with relevant spinal disease[10, 18, 35].

Thus, conscious perception and unconscious effects originating from the vertebral column, its neural structures and the surrounding tissues, although complex, have definite pathways represented in this network of peripheral and central nervous system (CNS) ramifications. Although the model for this discussion will center on the lumbosacral spine, the particulars apply to all levels of the spine, after allowing for regional modifications.

ANATOMY OF LOCAL SPINAL SYNDROMES

Somatic Innervation of Ventral Spinal Elements

Innervation of the ventral spinal tissues rests partially with afferent somatic fibers originating from the recurrent meningeal nerve (sinuvertebral nerve of von Luschka) supplying the posterior longitudinal ligament, the meninges of the anterior aspect of the thecal sac, the regional anterior epidural blood vessels (arteries and veins), the posterior

aspect of the outermost fibers of the annulus fibrosis, the anterior and posterior longitudinal ligaments and the posterior portion of the periosteum of the vertebral body and related tissues over an inconstant range. 

In addition, irregular, unnamed afferent branches directly emanating from the ventral rami of the somatic spinal nerves themselves also contribute to direct spinal and adjacent perispinal soft tissue innervation laterally. Thus,

these well-defined somatic neural networks form the anatomic basis for discogenic (intervertebral disc), spondylogenic (spinal bony structures), musculogenic  (intrinsic spinal and external perispinal muscles), ligamentogenic (intrinsic spinal ligaments) normal sensation and pathologic pain [23, 36, 45, 48, 74, 90, 91].

Any insult of these neural and non-neural tissues may incite well-circumscribed local somatic pain because of this characteristic somatosensory innervation pattern (figure 1), and because of the direct segmental nature of the afferent inflow from the segment of origin into the CNS via the somatic spinal nerves (figure 2a) [6, 9, 20, 23, 29, 38, 52, 63, 87, 90, 91]. This direct somatosensory afferent inflow seems to embryologically insure a relatively accurate CNS

somatotopic spatial registration of impulses incoming into the CNS with regard to stimulus origin, and thus local spine pain.

 

1=nucleus pulposus; 2=annulus fibrosus;  3=anterior longitudinal ligament/periosteum; 4=posterior longitudinal ligament/periosteum; 5=thecal sac;  6=tissues within anterior epidural space [e.g.,epidural vasculature]; 

7=filum terminale;  8=intrathecal nerve root [s] of the cauda equine;  9=ventral nerve root; 10=dorsal nerve root; 

11=dorsal root ganglion;  12=dorsal ramus of spinal nerve;  13=ventral ramus of spinal nerve; 14=recurrent meningeal nerve [sinuvertebral nerve of Luschka]; 15=connecting sympathetic branch from gray ramus communicans to the sinuvertebral nerve of Luschka [sympathetic branch to recurrent meningeal nerve];  16=neural radicals from sinuvertebral nerve of Luschka to posterior and lateral aspect of intervertebral disc surface; 17=white ramus communicans [not found or found irregularly caudal to L2];  18=gray ramus communicans;  19=sympathetic neural radicals to lateral disc surface from gray ramus communicans; 20=paraspinal sympathetic ganglion [PSG];

21=paraspinal sympathetic chain on left side [replicated on right side: not shown]; 22=anterior branch from sympathetic ganglion to anterior disc surface;  23=branches from sympathetic chain to anterior disc surface.

Somatic Innervation of Dorsal Spinal Elements

The dorsal rami of the spinal nerves give rise to medial and lateral main branches. These neural structures innervate the posterior spinal facet (zygapophyseal) joints (bone, periosteum, articular structures including the joint capsule), the lateral and posterior vertebral bony elements (laminae, transverse and spinous processes), as well as the surrounding posterior (dorsal) intrinsic spinal and perispinal muscular (multifidus, interspinalis muscles), and ligamentous tissues (interspinous ligament, supraspinous ligament).

In total there are potentially five or more main branches innervating these structures that are of somewhat irregular origin. These branches include neural fibers arising directly from the main trunk of the dorsal ramus of the spinal nerve, from the medial branch of the dorsal ramus, from the lateral branch of the dorsal ramus, and from the combined spinal nerve itself before its bifurcation into the dorsal and ventral rami (figure 3) [2, 5, 8].

On careful anatomic study, the dorsal elements of the spinal column and surrounding tissues have been demonstrated to have remarkably variable fields of innervation that are not confined to strict segmental patterns. This innervation shows bilateral asymmetry with intra- and interindividual variation in the craniocaudal extent of the neural supply.

Nevertheless, injury to these neural and non-neural spinal/perispinal tissues would in part, be expected to result in well localized somatic pain because of the direct afferent somatosensory inflow into the CNS via the retrospective somatic spinal nerves. Thus, in general this neural handling of pain seems to occur in a manner similar to that outlined above for the ventral spinal elements (figure 2a). 

In other words, these neural structures contribute to direct posterior (dorsal) spinal and perispinal soft tissue innervation, and thus somatic spondylogenic, (posterior bony spinal tissues), articulogenic (posterior spinal facet joints), ligamentogenic (ligamenta flava, interspinous ligament, supraspinous ligament) and musculogenic (multifidus, interspinalis muscles) normal sensation and local spinal pain [1, 10, 36, 45, 48, 74, 91].

Additional Considerations in the Innervation of Spinal Elements

Local innervations at the level of the dorsal and ventral roots, spinal nerves, recurrent meningeal nerves and other epidural structures at the point of common expression‎ of pathology (e.g., intervertebral disc herniation, spinal stenosis) is an important consideration regarding the understanding of the manifestations of the lumbosacral syndromes.

In addition to peripheral and local somatic afferent sensory and efferent motor nerves traversing this region (figure 4a-c), there are nerve fibers innervating the nerves themselves, the nervi nervorum [21].

These nervi nervorum are theoretically of three types. First, there are afferent somatic sensory fibers to the main nerve radicles in, traversing and around the spinal column (figure 4d). These are responsible for local sensation and even pain when the nerve itself is perturbed or nonspecifically injured. Second, there are local tissue and intrinsic radicular sympathetic afferent fibers. Upon leaving the spine, these fibers enter the paraspinal sympathetic chain via the gray rami communicants and return to the CNS via the white rami communicantes (figure 4e). These fibers relay afferent

information from the spinal roots, nerves and surrounding tissues to the somatic and sympathetic nervous systems. Third, there are local/radicular sympathetic efferent fibers which carry out sympathetic actions (e.g., vasoactive functions) upon the spinal roots, nerves and surrounding tissues (figure 4f).

This general format of spinal innervation is likely replicated in its essential points in the spinal and perispinal tissues, the autonomic fibers being initially transmitted via the dorsal roots of the spinal nerves, and later traveling in company with the blood vessels supplying these tissues (figure 4g-h) [2, 7, 16].

With this level of neuroanatomic complexity, it is not surprising that pathology affecting this particular region would be expected to potentially be somewhat confusing in its clinical manifestations. All possible somatoautonomic expressions (e.g., local pain, referred pain, radicular pain, autonomic dysfunction [see below]) could possibly emanate from this network of afferent and efferent fibers that traverse this area as well as originate and terminate here. 

At the same time, injury to somatic efferent motor fibers contained in the ventral/dorsal rami of the spinal nerve or the spinal nerve itself might yield muscular weakness, spasm and muscle reflex dysfunction. This surely must be one of the more neurologically labyrinthine regions in the entire peripheral nervous system. Why each patient might be expected to have a unique and compound-complex array of signs and symptoms can be easily appreciated if these intimately related anatomic neural ramifications are taken into account.