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Posterior interosseous nerve syndrome with hourglass-like fascicular constriction of the nerve
Journal of the Neurological Sciences 215 (2003) 111 – 113 www.elsevier.com/locate/jns
Short communication
Posterior interosseous nerve syndrome with hourglass-like fascicular constriction of the nerve Fujio Umehara a,*, Shinji Yoshino b, Yumiko Arimura a, Tadahiro Fukuoka c, Kimiyoshi Arimura a, Mitsuhiro Osame a a
The Third Department of Internal Medicine, Kagoshima University School of Medicine, Sakuragaoka 8-35-1, Kagoshima 890, Japan b The Department of Orthopedics, Kagoshima University, Kagoshima, Japan c The Department of Internal Medicine, Izumi City Hospital, Izumi, Japan Received 24 February 2003; received in revised form 8 April 2003; accepted 15 May 2003
Abstract We describe a case of the posterior interosseous nerve (PIN) syndrome in a patient with gout. Exploration of the PIN revealed multiple hourglass-like constriction of the PIN, which did not correspond to any extrinsic compressing structures. Hourglass-like constrictions of the PIN is one of the causes of the painful PIN syndrome. D 2003 Elsevier B.V. All rights reserved. Keywords: Posterior interosseous nerve; Hourglass-like fascicular constriction; Radial nerve palsy; Painful neuropathy; Neuralgic amyotrophy
1. Introduction
2. Case report
The posterior interosseous nerve (PIN), the terminal motor branch of the radial nerve, also called the deep radial nerve, is located in the proximal third of the forearm. The PIN syndrome is caused by acute trauma, masses compressing the nerve (such as lipomas, ganglions, or bursae), and an inflammatory canal syndrome of epicondylalgias which will involve compression at the level of the arcade of Frohse. The PIN descends, passing over the anterior aspect of the radio-humeral joint. The most proximal part of the superficial head of the supinator muscle forms, 3– 5 cm below the lateral epicondyle, a fibrous arch or arcade of Frohse. The syndrome has been considered to result from intermittent and dynamic compression of the nerve in the proximal part of the forearm associated with repeated pronation and supination. Recently, hourglass-like fascicular constriction of peripheral nerves has been reported to be found in focal peripheral nerve paralysis [1– 3]. In the present study, we report a case of PIN syndrome associated with hourglasslike fascicular constriction of PIN in a patient with gout.
2.1. History
* Corresponding author. Tel.: +81-99-275-5332; fax: +81-99-2657164. E-mail address: [email protected] (F. Umehara). 0022-510X/03/$ - see front matter D 2003 Elsevier B.V. All rights reserved. doi:10.1016/S0022-510X(03)00164-3
A 51-year-old man, a right-handed carpenter, was attended to because of an aching pain on the left forearm and inability to extend the fingers actively. At the age of 48, he had an attack of gout involving the foot; however, he had no medication afterwards. Since late in July 2002, he noticed mild left forearm pain. Soon afterwards the pain was followed by severe pain throughout the left forearm, and he became unable to extend the fingers of the left hand. Spinal epidural anesthesia partially relieved his pain, however, his muscle weakness in the left hand did not improve. In September 2002, he was referred to our hospital. At first examination, there was tenderness on the distribution of the radial nerve 3– 5 cm distal to the elbow joint. Neurological examination revealed complete palsy of the following muscles (extensor carpi ulnaris, extensor digitorum communis, abductor pollicis longus, extensor pollicis longus), however, other muscles (including brachioradialis, extensor carpi radialis, biceps, triceps, flexor pollicis longus, abductor pollici interosseous palmaris) were normal. There was no sensory impairment. Deep tendon reflexes were normal, and pathological reflex was negative. Electrophysiological examinations revealed active
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F. Umehara et al. / Journal of the Neurological Sciences 215 (2003) 111–113
Fig. 1. Two hourglass-like fascicular constrictions on the PIN (arrow). The arrow head indicates the branch nerve to the extensor carpi radialis muscle.
denervation potentials which selectively involved muscles innervated by the PIN such as extensor carpi ulnaris and extensor digitorum communis. Nerve conduction in the median and ulnar nerves were normal. Magnetic resonance imaging (MRI) of the right forearm did not reveal any abnormalities. Serum uric acid level was 8.5 mg/dl (normal; 2.0 –6.5 mg/dl). 2.2. Operation The patient underwent surgery 2 months after onset of symptoms. The radial nerve was exposed in the superior half of the right forearm. The PIN was swollen and elastic hard (Fig. 1). Two portions of hourglass-like constrictions were found in the left PIN. The constrictions did not correspond to any extrinsic compressing structures. Electrical stimulation of the PIN did not evoke muscle contraction in the ulnar carpi ulnaris muscle. Epineurial tissues were carefully removed from the PIN. The muscle weakness did not recovered 3 months after surgery.
3. Discussion We present a case of paralyzing hourglass-like fascicular constrictions of the PIN that could not be attributed to extrinsic compression. So far, only a few cases of spontaneous, acute radial nerve palsy have been reported [2 –4]. In these cases, clinical presentation consisted of acute pain followed shortly by palsy of the extensor muscles of the wrist and fingers. Surgical exploration almost always reveals a mid-upper level radial nerve lesion, which appears as an hourglass-shaped constricted segment that is totally unrelated to any compressive structures. The clinical features of these cases are quite consistent with that of the present case. Thus, hourglasslike fascicular constrictions of the radial nerve may be
one of the causes of radial nerve palsies including the PIN syndrome. The PIN syndrome may present in one of the two distinct pathways: with a painless palsy or as a painful condition that is often difficult to distinguish from lateral epicondylitis (‘‘tennis elbow’’). The latter, painful condition typically does not involve any significant weakness. In addition to lateral epicondylitis, neuralgic amyotrophy is a differential diagnostic consideration. Parsonage and Turner, in 1948, reported five cases of anterior interosseous nerve palsy as manifestations of neuralgic amyotrophy [5]. Hourglass-like fascicular constriction has been reported not only in PIN, but also in anterior interosseous nerve [1]. Thus, hourglasslike fascicular constrictions of the peripheral nerves should be considered as differential diagnosis for painful focal neuropathies. The pathogenesis of the hourglass-like constrictions of the radial nerve remains unknown. Mechanical torsion by rolling of the fascicles during forearm flexion – extension or pronation – supination has been considered as a possible cause [6,7]. Some cases were relegated to medical disorders including polyarteritis and allergic angioneuropathy. In patients affected by vasculitis, intrafascicular edema due to chronic hypoperfusion is considered a possible cause of isolated nerve constriction and intraneural scarring. In patients with multiple hourglass-like constrictions of anterior and posterior interosseous nerves, pathological examination of epineurium from the constricted segment revealed invasion of inflammatory cells [1]. These findings suggest that the inflammatory response might be involved in the pathogenesis of multiple hourglass-like constrictions. Although the present patient had been suffering from gout, the PIN syndrome associated with gout has not been reported in the literature. Therefore, further studies will be required to confirm the cause of hourglass-like fascicular constriction in the present case.
Acknowledgements We thank Dr. Arlene R. Ng for critical reading of the manuscript.
References [1] Omura T, Nagano A, Murata H, Takahashi M, Ogihara H, Omura K. Simultaneous anterior and posterior interosseous nerve paralysis with several hourglass-like fascicular constrictions in both nerves. J Hand Surg 2001;26A:1088 – 92. [2] Burns J, Lister GD. Localized constrictive radial neuropathy in the absence of extrinsic compression: three cases. J Hand Surg 1984;9A: 99 – 103. [3] Fernandez E, Rienzo AD, Marchese E, Massimi L, Lauretti L, Pallini R. Radial nerve palsy caused by spontaneously occurring nerve torsion. J Neurosurg 2001;94:627 – 9. [4] Belsole RJ, Lister DG, Kleinert HE. Polyarteritis: a cause of nerve palsy in the extremity. J Hand Surg 1978;3:320 – 5.
F. Umehara et al. / Journal of the Neurological Sciences 215 (2003) 111–113 [5] Parsonage MJ, Turner JW. Neuralgic amyotrophy—the shoulder girdle syndrome. Lancet 1948;2:973 – 8. [6] Hausmann P, Patel MR. Intraperineurial constriction of nerve fascicles in pronator syndrome and anterior interosseous nerve syndrome. Orthop Clin North Am 1996;27:339 – 44.
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[7] Nakamura M, Suganuma E, Tanaka M, Ishizuki M, Huruya K. A case report of the anterior interosseous nerve palsy in which one of the two funiculi was found twisted at about five cm proximal to the elbow. J Jpn Soc Surg Hand 1992;8:986 – 9.
Short communication
Posterior interosseous nerve syndrome with hourglass-like fascicular constriction of the nerve Fujio Umehara a,*, Shinji Yoshino b, Yumiko Arimura a, Tadahiro Fukuoka c, Kimiyoshi Arimura a, Mitsuhiro Osame a a
The Third Department of Internal Medicine, Kagoshima University School of Medicine, Sakuragaoka 8-35-1, Kagoshima 890, Japan b The Department of Orthopedics, Kagoshima University, Kagoshima, Japan c The Department of Internal Medicine, Izumi City Hospital, Izumi, Japan Received 24 February 2003; received in revised form 8 April 2003; accepted 15 May 2003
Abstract We describe a case of the posterior interosseous nerve (PIN) syndrome in a patient with gout. Exploration of the PIN revealed multiple hourglass-like constriction of the PIN, which did not correspond to any extrinsic compressing structures. Hourglass-like constrictions of the PIN is one of the causes of the painful PIN syndrome. D 2003 Elsevier B.V. All rights reserved. Keywords: Posterior interosseous nerve; Hourglass-like fascicular constriction; Radial nerve palsy; Painful neuropathy; Neuralgic amyotrophy
1. Introduction
2. Case report
The posterior interosseous nerve (PIN), the terminal motor branch of the radial nerve, also called the deep radial nerve, is located in the proximal third of the forearm. The PIN syndrome is caused by acute trauma, masses compressing the nerve (such as lipomas, ganglions, or bursae), and an inflammatory canal syndrome of epicondylalgias which will involve compression at the level of the arcade of Frohse. The PIN descends, passing over the anterior aspect of the radio-humeral joint. The most proximal part of the superficial head of the supinator muscle forms, 3– 5 cm below the lateral epicondyle, a fibrous arch or arcade of Frohse. The syndrome has been considered to result from intermittent and dynamic compression of the nerve in the proximal part of the forearm associated with repeated pronation and supination. Recently, hourglass-like fascicular constriction of peripheral nerves has been reported to be found in focal peripheral nerve paralysis [1– 3]. In the present study, we report a case of PIN syndrome associated with hourglasslike fascicular constriction of PIN in a patient with gout.
2.1. History
* Corresponding author. Tel.: +81-99-275-5332; fax: +81-99-2657164. E-mail address: [email protected] (F. Umehara). 0022-510X/03/$ - see front matter D 2003 Elsevier B.V. All rights reserved. doi:10.1016/S0022-510X(03)00164-3
A 51-year-old man, a right-handed carpenter, was attended to because of an aching pain on the left forearm and inability to extend the fingers actively. At the age of 48, he had an attack of gout involving the foot; however, he had no medication afterwards. Since late in July 2002, he noticed mild left forearm pain. Soon afterwards the pain was followed by severe pain throughout the left forearm, and he became unable to extend the fingers of the left hand. Spinal epidural anesthesia partially relieved his pain, however, his muscle weakness in the left hand did not improve. In September 2002, he was referred to our hospital. At first examination, there was tenderness on the distribution of the radial nerve 3– 5 cm distal to the elbow joint. Neurological examination revealed complete palsy of the following muscles (extensor carpi ulnaris, extensor digitorum communis, abductor pollicis longus, extensor pollicis longus), however, other muscles (including brachioradialis, extensor carpi radialis, biceps, triceps, flexor pollicis longus, abductor pollici interosseous palmaris) were normal. There was no sensory impairment. Deep tendon reflexes were normal, and pathological reflex was negative. Electrophysiological examinations revealed active
112
F. Umehara et al. / Journal of the Neurological Sciences 215 (2003) 111–113
Fig. 1. Two hourglass-like fascicular constrictions on the PIN (arrow). The arrow head indicates the branch nerve to the extensor carpi radialis muscle.
denervation potentials which selectively involved muscles innervated by the PIN such as extensor carpi ulnaris and extensor digitorum communis. Nerve conduction in the median and ulnar nerves were normal. Magnetic resonance imaging (MRI) of the right forearm did not reveal any abnormalities. Serum uric acid level was 8.5 mg/dl (normal; 2.0 –6.5 mg/dl). 2.2. Operation The patient underwent surgery 2 months after onset of symptoms. The radial nerve was exposed in the superior half of the right forearm. The PIN was swollen and elastic hard (Fig. 1). Two portions of hourglass-like constrictions were found in the left PIN. The constrictions did not correspond to any extrinsic compressing structures. Electrical stimulation of the PIN did not evoke muscle contraction in the ulnar carpi ulnaris muscle. Epineurial tissues were carefully removed from the PIN. The muscle weakness did not recovered 3 months after surgery.
3. Discussion We present a case of paralyzing hourglass-like fascicular constrictions of the PIN that could not be attributed to extrinsic compression. So far, only a few cases of spontaneous, acute radial nerve palsy have been reported [2 –4]. In these cases, clinical presentation consisted of acute pain followed shortly by palsy of the extensor muscles of the wrist and fingers. Surgical exploration almost always reveals a mid-upper level radial nerve lesion, which appears as an hourglass-shaped constricted segment that is totally unrelated to any compressive structures. The clinical features of these cases are quite consistent with that of the present case. Thus, hourglasslike fascicular constrictions of the radial nerve may be
one of the causes of radial nerve palsies including the PIN syndrome. The PIN syndrome may present in one of the two distinct pathways: with a painless palsy or as a painful condition that is often difficult to distinguish from lateral epicondylitis (‘‘tennis elbow’’). The latter, painful condition typically does not involve any significant weakness. In addition to lateral epicondylitis, neuralgic amyotrophy is a differential diagnostic consideration. Parsonage and Turner, in 1948, reported five cases of anterior interosseous nerve palsy as manifestations of neuralgic amyotrophy [5]. Hourglass-like fascicular constriction has been reported not only in PIN, but also in anterior interosseous nerve [1]. Thus, hourglasslike fascicular constrictions of the peripheral nerves should be considered as differential diagnosis for painful focal neuropathies. The pathogenesis of the hourglass-like constrictions of the radial nerve remains unknown. Mechanical torsion by rolling of the fascicles during forearm flexion – extension or pronation – supination has been considered as a possible cause [6,7]. Some cases were relegated to medical disorders including polyarteritis and allergic angioneuropathy. In patients affected by vasculitis, intrafascicular edema due to chronic hypoperfusion is considered a possible cause of isolated nerve constriction and intraneural scarring. In patients with multiple hourglass-like constrictions of anterior and posterior interosseous nerves, pathological examination of epineurium from the constricted segment revealed invasion of inflammatory cells [1]. These findings suggest that the inflammatory response might be involved in the pathogenesis of multiple hourglass-like constrictions. Although the present patient had been suffering from gout, the PIN syndrome associated with gout has not been reported in the literature. Therefore, further studies will be required to confirm the cause of hourglass-like fascicular constriction in the present case.
Acknowledgements We thank Dr. Arlene R. Ng for critical reading of the manuscript.
References [1] Omura T, Nagano A, Murata H, Takahashi M, Ogihara H, Omura K. Simultaneous anterior and posterior interosseous nerve paralysis with several hourglass-like fascicular constrictions in both nerves. J Hand Surg 2001;26A:1088 – 92. [2] Burns J, Lister GD. Localized constrictive radial neuropathy in the absence of extrinsic compression: three cases. J Hand Surg 1984;9A: 99 – 103. [3] Fernandez E, Rienzo AD, Marchese E, Massimi L, Lauretti L, Pallini R. Radial nerve palsy caused by spontaneously occurring nerve torsion. J Neurosurg 2001;94:627 – 9. [4] Belsole RJ, Lister DG, Kleinert HE. Polyarteritis: a cause of nerve palsy in the extremity. J Hand Surg 1978;3:320 – 5.
F. Umehara et al. / Journal of the Neurological Sciences 215 (2003) 111–113 [5] Parsonage MJ, Turner JW. Neuralgic amyotrophy—the shoulder girdle syndrome. Lancet 1948;2:973 – 8. [6] Hausmann P, Patel MR. Intraperineurial constriction of nerve fascicles in pronator syndrome and anterior interosseous nerve syndrome. Orthop Clin North Am 1996;27:339 – 44.
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[7] Nakamura M, Suganuma E, Tanaka M, Ishizuki M, Huruya K. A case report of the anterior interosseous nerve palsy in which one of the two funiculi was found twisted at about five cm proximal to the elbow. J Jpn Soc Surg Hand 1992;8:986 – 9.