The double nature of the intermediate dense line in peripheral nerve myelin

1969 ◽  
Vol 163 (1) ◽  
pp. 7-15 ◽  
Author(s):  
Jean-Paul Revel ◽  
David W. Hamilton
Keyword(s):  
Peripheral Nerve ◽  
Dense Line ◽  
Double Nature

Facilitated migration of cells from a transected peripheral nerve over collagen fibers: in vivo observations

1989 ◽  
Vol 47 ◽  
pp. 888-889
Author(s):  
Arthur J. Wasserman ◽  
Azam Rizvi ◽  
George Zazanis ◽  
Frederick H. Silver
Keyword(s):  
Sciatic Nerve ◽  
Peripheral Nerve ◽  
Collagen Gel ◽  
Collagen Fibers ◽  
Control Group ◽  
Guide Tube ◽  
Sprague Dawley ◽  
Silicone Tube ◽  
Thin Sections

In cases of peripheral nerve damage the gap between proximal and distal stumps can be closed by suturing the ends together, using a nerve graft, or by nerve tubulization. Suturing allows regeneration but does not prevent formation of painful neuromas which adhere to adjacent tissues. Autografts are not reported to be as good as tubulization and require a second surgical site with additional risks and complications. Tubulization involves implanting a nerve guide tube that will provide a stable environment for axon proliferation while simultaneously preventing formation of fibrous scar tissue. Supplementing tubes with a collagen gel or collagen plus extracellular matrix factors is reported to increase axon proliferation when compared to controls. But there is no information regarding the use of collagen fibers to guide nerve cell migration through a tube. This communication reports ultrastructural observations on rat sciatic nerve regeneration through a silicone nerve stent containing crosslinked collagen fibers.Collagen fibers were prepared as described previously. The fibers were threaded through a silicone tube to form a central plug. One cm segments of sciatic nerve were excised from Sprague Dawley rats. A control group of rats received a silicone tube implant without collagen while an experimental group received the silicone tube containing a collagen fiber plug. At 4 and 6 weeks postoperatively, the implants were removed and fixed in 2.5% glutaraldehyde buffered by 0.1 M cacodylate containing 1.5 mM CaCl2 and balanced by 0.1 M sucrose. The explants were post-fixed in 1% OSO4, block stained in 1% uranyl acetate, dehydrated and embedded in Epon. Axons were counted on montages prepared at a total magnification of 1700x. Montages were viewed through a dissecting microscope. Thin sections were sampled from the proximal, middle and distal regions of regenerating sciatic plugs.

Peripheral Nerve and Brachial Plexus Impairment, AMA Guides, Sixth Edition

2017 ◽  
Vol 22 (2) ◽  
pp. 3-5
Author(s):  
James B. Talmage ◽  
Jay Blaisdell
Keyword(s):  
Peripheral Nerve ◽  
Brachial Plexus ◽  
Complex Regional Pain Syndrome ◽  
Lower Extremities ◽  
Pain Syndrome ◽  
Upper Extremities ◽  
Motor Deficits ◽  
Type I ◽  
Sixth Edition ◽  
Nerve Entrapments

Abstract Physicians use a variety of methodologies within the AMA Guides to the Evaluation of Permanent Impairment (AMA Guides), Sixth Edition, to rate nerve injuries depending on the type of injury and location of the nerve. Traumatic injuries that cause impairment to the peripheral or brachial plexus nerves are rated using Section 15.4e, Peripheral Nerve and Brachial Plexus Impairment, for upper extremities and Section 16.4c, Peripheral Nerve Rating Process, for lower extremities. Verifiable nerve lesions that incite the symptoms of complex regional pain syndrome, type II (similar to the former concept of causalgia), also are rated in these sections. Nerve entrapments, which are not isolated traumatic events, are rated using the methodology in Section 15.4f, Entrapment Neuropathy. Type I complex regional pain syndrome is rated using Section 15.5, Complex Regional Pain Syndrome for upper extremities or Section 16.5, Complex Regional Pain Syndrome for lower extremities. The method for grading the sensory and motor deficits is analogous to the method described in previous editions of AMA Guides. Rating the permanent impairment of the peripheral nerves or brachial plexus is similar to the methodology used in the diagnosis-based impairment scheme with the exceptions that the physical examination grade modifier is never used to adjust the default rating and the names of individual nerves or plexus trunks, as opposed to the names of diagnoses, appear in the far left column of the rating grids.

Evaluating Shoulder Impairment

1998 ◽  
Vol 3 (5) ◽  
pp. 1-3
Author(s):  
Richard T. Katz ◽  
Sankar Perraraju
Keyword(s):  
Peripheral Nerve ◽  
Upper Extremity ◽  
Sensory Loss ◽  
Motor Deficits ◽  
Nerve Lesion ◽  
Fourth Edition ◽  
Specific Patient ◽  
Industrial Medicine ◽  
Shoulder Motion ◽  
Upper Extremity Impairment

Abstract The AMA Guides to the Evaluation of Permanent Impairment (AMA Guides), Fourth Edition, offers several categories to describe impairment in the shoulder, including shoulder amputation, abnormal shoulder motion, peripheral nerve disorders, subluxation/dislocation, and joint arthroplasty. This article clarifies appropriate methods for rating shoulder impairment in a specific patient, particularly with reference to the AMA Guides, Section 3.1j, Shoulder, Section 3.1k, Impairment of the Upper Extremity Due to Peripheral Nerve Disorders, and Section 3.1m, Impairment Due to Other Disorders of the Upper Extremity. A table shows shoulder motions and associated degrees of motion and can be used in assessing abnormal range of motion. Assessments of shoulder impairment due to peripheral nerve lesion also requires assessment of sensory loss (or presence of nerve pain) or motor deficits, and these may be categorized to the level of the spinal nerves (C5 to T1). Table 23 is useful regarding impairment from persistent joint subluxation or dislocation, and Table 27 can be helpful in assessing impairment of the upper extremity after arthroplasty of specific bones of joints. Although inter-rater reliability has been reasonably good, the validity of the upper extremity impairment rating has been questioned, and further research in industrial medicine and physical disability is required.

Techniques of Peripheral Nerve Repair

1991 ◽  
Vol 2 (1) ◽  
pp. 93-104 ◽  
Author(s):  
Mark E. Harris ◽  
Suzie C. Tindall
Keyword(s):  
Peripheral Nerve ◽  
Nerve Repair ◽  
Peripheral Nerve Repair

Peripheral Nerve Injuries of the Shoulder in the Athlete

1990 ◽  
Vol 9 (2) ◽  
pp. 331-342 ◽  
Author(s):  
Francis X. Mendoza ◽  
Kenneth Main
Keyword(s):  
Peripheral Nerve ◽  
Peripheral Nerve Injuries ◽  
Nerve Injuries
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