Biomaterial Database

Effects of experimental graded compression on blood flow in spinal nerve roots. A vital microscopic study on the porcine cauda equina. 1989

K Olmarker, and B Rydevik, and S Holm, and U Bagge

Department of Anatomy, Sahlgren Hospital, Gothenburg University, Sweden.

Compression injuries of spinal nerve roots are very common. However, the basic pathophysiology of these conditions is not fully understood. In this study a model is presented for experimental graded compression of the nerve roots of the pig cauda equina, including a technique for vital microscopic studies on the microcirculation flow of the intrinsic vessels of the nerve roots during compression. With this model critical pressure levels for compression-induced occlusion of the arterioles, capillaries, and venules of the intrinsic vasculature of the nerve roots were determined. The study showed that the average minimum pressure in the inflated balloon required to stop the flow in the arterioles was 127 mm Hg (SD = 18, n = 11), in the capillaries 40 mm Hg (SD = 6, n = 12), and in the venules 30 mm Hg (SD = 10, n = 12). The average mean arterial pressure (MAP) was 150 mm Hg (SD = 14, n = 12). There was a statistically significant correlation (p greater than 0.001) between the MAP and the pressure required to stop the flow in the arterioles (r = 0.83, n = 14), but no correlation between MAP and capillary (r = 0.09 NS, n = 20) or venular (r = -0.28 NS, n = 34) occlusion pressure. After the nerve roots had been compressed at 50 or 200 mm Hg for 10 min or 2 h, the recirculation started immediately. There was a hyperemia during the first 10 min, with a dilatation of the vessels, particularly the venules. In nerve roots exposed to compression for 2 h at either 50 or 200 mm Hg, an intraneural edema developed.(ABSTRACT TRUNCATED AT 250 WORDS)

UI	MeSH Term	Description	Entries
D007511	Ischemia	A hypoperfusion of the BLOOD through an organ or tissue caused by a PATHOLOGIC CONSTRICTION or obstruction of its BLOOD VESSELS, or an absence of BLOOD CIRCULATION.	Ischemias
D009408	Nerve Compression Syndromes	Mechanical compression of nerves or nerve roots from internal or external causes. These may result in a conduction block to nerve impulses (due to MYELIN SHEATH dysfunction) or axonal loss. The nerve and nerve sheath injuries may be caused by ISCHEMIA; INFLAMMATION; or a direct mechanical effect.	Entrapment Neuropathies,Nerve Entrapments,External Nerve Compression Syndromes,Internal Nerve Compression Syndromes,Nerve Compression Syndromes, External,Nerve Compression Syndromes, Internal,Compression Syndrome, Nerve,Compression Syndromes, Nerve,Entrapment, Nerve,Entrapments, Nerve,Nerve Compression Syndrome,Nerve Entrapment,Neuropathies, Entrapment,Neuropathy, Entrapment,Syndrome, Nerve Compression,Syndromes, Nerve Compression
D011312	Pressure	A type of stress exerted uniformly in all directions. Its measure is the force exerted per unit area. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Pressures
D001775	Blood Circulation	The movement of the BLOOD as it is pumped through the CARDIOVASCULAR SYSTEM.	Blood Flow,Circulation, Blood,Blood Flows,Flow, Blood
D002420	Cauda Equina	The lower part of the SPINAL CORD consisting of the lumbar, sacral, and coccygeal nerve roots.	Filum Terminale,Equina, Cauda,Terminale, Filum
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D013119	Spinal Cord Injuries	Penetrating and non-penetrating injuries to the spinal cord resulting from traumatic external forces (e.g., WOUNDS, GUNSHOT; WHIPLASH INJURIES; etc.).	Myelopathy, Traumatic,Injuries, Spinal Cord,Post-Traumatic Myelopathy,Spinal Cord Contusion,Spinal Cord Laceration,Spinal Cord Transection,Spinal Cord Trauma,Contusion, Spinal Cord,Contusions, Spinal Cord,Cord Contusion, Spinal,Cord Contusions, Spinal,Cord Injuries, Spinal,Cord Injury, Spinal,Cord Laceration, Spinal,Cord Lacerations, Spinal,Cord Transection, Spinal,Cord Transections, Spinal,Cord Trauma, Spinal,Cord Traumas, Spinal,Injury, Spinal Cord,Laceration, Spinal Cord,Lacerations, Spinal Cord,Myelopathies, Post-Traumatic,Myelopathies, Traumatic,Myelopathy, Post-Traumatic,Post Traumatic Myelopathy,Post-Traumatic Myelopathies,Spinal Cord Contusions,Spinal Cord Injury,Spinal Cord Lacerations,Spinal Cord Transections,Spinal Cord Traumas,Transection, Spinal Cord,Transections, Spinal Cord,Trauma, Spinal Cord,Traumas, Spinal Cord,Traumatic Myelopathies,Traumatic Myelopathy
D013126	Spinal Nerve Roots	Paired bundles of NERVE FIBERS entering and leaving the SPINAL CORD at each segment. The dorsal and ventral nerve roots join to form the mixed segmental spinal nerves. The dorsal roots are generally afferent, formed by the central projections of the spinal (dorsal root) ganglia sensory cells, and the ventral roots are efferent, comprising the axons of spinal motor and PREGANGLIONIC AUTONOMIC FIBERS.	Dorsal Roots,Spinal Roots,Ventral Roots,Dorsal Root,Nerve Root, Spinal,Nerve Roots, Spinal,Root, Dorsal,Root, Spinal,Root, Spinal Nerve,Root, Ventral,Roots, Dorsal,Roots, Spinal,Roots, Spinal Nerve,Roots, Ventral,Spinal Nerve Root,Spinal Root,Ventral Root
D013552	Swine	Any of various animals that constitute the family Suidae and comprise stout-bodied, short-legged omnivorous mammals with thick skin, usually covered with coarse bristles, a rather long mobile snout, and small tail. Included are the genera Babyrousa, Phacochoerus (wart hogs), and Sus, the latter containing the domestic pig (see SUS SCROFA).	Phacochoerus,Pigs,Suidae,Warthogs,Wart Hogs,Hog, Wart,Hogs, Wart,Wart Hog
D014699	Venules	The minute vessels that collect blood from the capillary plexuses and join together to form veins.	Venule