Spontaneous anterior interosseous nerve palsy with hourglass-like fascicular constriction within the main trunk of the median nerve

Parsonage-turner syndrome

Parsonage-Turner Syndrome (PTS), also referred to as idiopathic brachial plexopathy or neuralgic amyotrophy, is a rare disorder consisting of a complex constellation of symptoms with abrupt onset of shoulder pain, usually unilaterally, followed by progressive neurologic deficits of motor weakness, dysesthesias, and numbness. Although the etiology of the syndrome is unclear, it is reported in various clinical situations, including postoperatively, postinfectious, posttraumatic, and postvaccination. The identification of the syndrome in the postoperative patient remains a challenge as symptoms may easily be attributed to sequelae of surgical positioning, postoperative recovery, or postanesthetic block pain. The purpose of this review is to bring forth salient, identifiable factors which may assist the surgical clinician in identifying the condition sooner. An early and proper diagnosis affords the opportunity to treat the patient accordingly and to the satisfaction of both surgeon and patient.

Homolateral hourglass-like constrictions of the axillary and suprascapular nerves: case report

In contrast with previous research, it was recently demonstrated that hourglass-like constriction is not exclusive to the elbow region. We present a report of a patient who had an axillary nerve and a suprascapular nerve hourglass-like constriction, found 7 years apart.

Hourglass-like constriction of the axillary nerve: report of two patients

Among the various etiologies of compressive lesions, the development of an hourglass-like constriction of the nerve that is unrelated to any recognizably compressive structure is a very rare phenomenon. This problem has been reported previously for the radial nerve and its branch posterior interosseous nerve and for the anterior interosseous nerve, a branch of median nerve. Here we report 2 cases of hourglass-like constriction of the axillary nerve that were observed during surgery; the constrictive segment was unrelated to any compressive structure.

Peripheral nerve fascicles: Anatomy and clinical relevance

Within a peripheral nerve, the individual nerve fibers are grouped together in fascicles. Whether there is somatotopic organization within these fascicles has long been of interest, the subject of many investigations, and somewhat controversial. Evidence from diverse sources now points to important somatotopic clustering of nerve fibers within most of the length of the nerve. Information is lacking regarding proximal segments, particularly the plexus and spinal nerve root levels. As a result of this somatotopic arrangement, partial focal nerve lesions can produce restricted clinical deficits that defy the classic rules of localization. Examples of such restricted nerve lesions are provided in this review. Recognition of fascicle somatotopy is also important in the surgical approach to disorders of peripheral nerves.

Compressive neuropathies of the upper extremity

Although any peripheral nerve may be compressed anywhere along its course, nerve compression syndromes typically occur at predictable sites with predictable clinical presentations. A detailed history and physical examination can establish a diagnosis, and electrodiagnostic studies and at times imaging can confirm it. Physicians should adopt a systematic approach of diagnosing and treating these types of nerve lesions. The physician and the patient can be rewarded with favorable outcomes.

Fascicular torsion in the median nerve within the distal third of the upper arm: three cases of nontraumatic anterior interosseous nerve palsy

Three patients with nontraumatic anterior interosseous nerve palsy are presented. All patients also had paralysis of the pronator teres, flexor carpi radialis, and/or palmaris longus. One patient also had sensory disturbance and palsy of the thenar muscles. An hourglass-like constriction was seen within a 7-cm section of the nerve fascicles (2-9 cm proximal from the medial epicondyle of the humerus) in the median nerve trunk. All constrictions exhibited approximately 30 degrees of fascicular torsion. Because this nerve section is anatomically proximal to the branching point for the earlier mentioned motor branches and the anterior interosseous nerve, the nerve fascicles may have been structurally twisted before the onset of palsy. Structural abnormalities causing inflammation and edema of nerve fascicles as well as factors such as compression from surrounding small vessels may have maximized torsion, resulting in the formation of constrictions.

Simultaneous anterior and posterior interosseous nerve paralysis with several hourglass-like fascicular constrictions in both nerves

A patient with simultaneous anterior and posterior interosseous nerve paralysis was treated surgically with interfascicular neurolysis and found to have several hourglass-like fascicular constrictions in both nerves. Anterior and posterior interosseous nerve paralyses with hourglass-like fascicular constrictions have been described previously, but not the combination of the two.

Nerve entrapment in athletes

Nerve entrapment syndromes can occur in athletes. The repetitive and vigorous use or overuse of the upper extremity makes the athlete particularly vulnerable to disorders of peripheral nerves. Understanding the clinical signs and symptoms is essential to treatment. The pertinent anatomy, clinical presentation, treatment, and rehabilitation necessary for return to sports for various nerve entrapments have been described. This should enable the physician caring for the athlete to help prevent injury and to guide appropriate treatment, if intervention becomes necessary.

Multiple constrictions of the radial nerve without external compression

We report a patient with multiple constrictions within the main trunk of the radial nerve that was found after epineurectomy and speculate that the etiology is an inflammatory response. (J Hand Surg 2000; 25A:134-137.