Düşünen Adam The Journal of Psychiatry and Neurological Sciences 2013;26:211-214 Case Report / Olgu Sunumu DOI: 10.5350/DAJPN2013260212 Isolated Axillary Nerve Betul Tekin Guveli1, Fikret Aysal2, Azize Esra Gursoy3, Involvement: A Case Report Mehmet Kolukisa3, Suna Askin4, Ahmet Hakyemez5, Arif Celebi3 1Neurologist, Bakirkoy Training and Research Hospital for Psychiatry Neurology and Neurosurgery, 1st Department of Neurology, Istanbul - Turkey 2Neurologist, Bakirkoy Training and Research Hospital for Psychiatry Neurology and Neurosurgery, 2nd Department of Neurology, Istanbul - Turkey 3Neurologist, Bezmialem Vakif University, Faculty of Medicine, Department of Neurology, Istanbul - Turkey 4Neurologist, Okmeydani Training and Research Hospital, Department of Neurology, Istanbul - Turkey 5Neurologist, Istanbul Training and Research Hospital, Department of Neurology, Istanbul - Turkey ABSTRACT Isolated axillary nerve involvement: a case report Isolated axillary neuropathy is a rare condition. Trauma to the shoulder, especially dislocation of the shoulder is the most common cause. The other causes of axillary neuropathy are injection to the shoulder, carrying heavy backpacks and acute idiopathic brachial plexus neropathy. Differential diagnosis should be made especially between cervical 5-6 radiculopathy and upper truncus brachial plexopathy. Case: A 32-year-old man admitted with progressive atrophy and weakness of the right shoulder which developed after deep pain. In his neurological examination, abduction weakness and atrophy of the right shoulder was determined. Magnetic resonance imaging findings of cervical spine and right shoulder were normal. Electrophysiologic examination revealed reduced compound muscle action potential amplitude of the right axillary nerve, recorded from deltoid muscle, compared to the left side. On needle EMG, subacute neurogenic signs in the right deltoid and teres minor muscles which are innervated by the axillary nerve were detected. Etiological evaluation revealed no cause. It has been suggested that isolated axillary neuropathy may be associated with Personage-Turner syndrome. Antiinflammatory medications and physical therapy provided partial improvement. The aim of our presentation was to discuss the differential diagnosis, treatment options and etiologic causes of axillary neuropathy. Key words: Axillary nerve, acute idiopathic brachial plexus neuropathy, EMG ÖZET İzole aksiller sinir tutulumu: Olgu sunumu Address reprint requests to / Yazışma adresi: Neurologist Betul Tekin Guveli, Bakirkoy İzole aksiller sinir tutulumu nadir görülen bir durumdur. En sık karşılaşılan neden omuz travması, özellikle omuz Training and Research Hospital for Psychiatry çıkığıdır. Omuza yapılan enjeksiyon, sırt çantası kullanımı veya akut idiyopatik brakiyal pleksus nöropatisi diğer Neurology and Neurosurgery, 1st Department etiyolojik nedenler olabilir. C5/C6 radikülopati, brakiyal pleksus üst trunkus tutulumu ile ayırıcı tanısı yapılmalıdır. of Neurology, Istanbul - Turkey Olgu: Sağ omuzda şiddetli ağrı sonrası güçsüzlük ve incelme gelişen, nörolojik muayenede sağ omuz Phone / Telefon: +90-212-543-6565 abdüksiyon zaafı ve atrofisi olan 32 yaşındaki erkek hastanın servikal spinal ve omuz MR incelemeleri normaldi. E-mail address / Elektronik posta adresi: Elektrofizyolojik incelemede, sağ aksiller sinir bileşik kas aksiyon potansiyeli, deltoid kasından kayıtlama ile sola [email protected] göre düşüktü. İğne elektromiyografisinde aksiller sinir inervasyonlu deltoid ve teres minör kaslarında subakut Date of receipt / Geliş tarihi: dönem nörojenik tutulum bulguları saptandı. Etiyolojik araştırmada neden bulunamadı. İzole aksiller sinir February 27, 2012 / 27 Şubat 2012 tutulumunun Personage-Turner Sendromuna bağlı olabileceği düşünüldü. Antienflamatuar ilaçlar ve fizik Date of acceptance / Kabul tarihi: tedavi ile hasta kısmen düzeldi. Vaka; ayırıcı tanı, tedavi ve etiyolojik nedenleri tartışmak amacı ile sunuldu. April 24, 2012 / 24 Nisan 2012 Anahtar kelimeler: Aksiller sinir, akut idiyopatik brakiyal pleksus nöropatisi, EMG INTRODUCTION passes laterally and posteriorly, and located under the shoulder joint. Then it travels through the quadrangular he axillary nerve is comprised of fibers from the space formed by neck of the humerus, long head of the TC5-C6 cervical nerve roots. It leaves upper truncus triceps, teres minor and teres major muscles. It divides and posterior cord of brachial plexus. Axillary nerve first into anterior and posterior branches in the deltoid extends from the lateral side of the radial nerve, then muscle. While its motor fibers innervate the deltoid and Düşünen Adam The Journal of Psychiatry and Neurological Sciences, Volume 26, Number 2, June 2013 211 Isolated axillary nerve involvement: a case report Left Right Figure 1: Axillary nerve motor conduction study. (Stimulation: Erb. Record: Deltoid muscle) Table 1: Other motor nerve conduction studies Table 2: Sensory nerve conduction studies Latance(ms) Amp(mV) C.V.(m/s) Peak latance (ms) Amp (μV) C.V.(m/s) Right median nerve Right median nerve Recording: APB Recording: Wrist Stimulation Stimulation Wrist 3.8 8.8 1. palm 3.4 26.6 Antecubital fossa 8.6 8.4 56.3 3. palm 3.6 29.6 Right ulnar nerve 2. palm 3.6 30.6 50.0 Recording: ADM Right ulnar nerve Stimulation Recording:Wrist Wrist 3.1 11.1 Stimulation Below elbow 8.2 10.3 51.0 5. palm 3.4 15.3 48.5 Above elbow 10.6 9.6 50.7 (Amp: Amplitude, ms: milisecond, μV: mikrovolt, C.V.: conduction velocity, m/s: meter/second) (ADM: Abductor digiti minimi muscle, APB: Abductor policis brevis muscle, Amp: Amplitude, mV: milivolt, ms: milisecond, CV: conduction velocity, m/s: meter/second) clinic due to severe right shoulder pain. He could not teres minor muscles, its sensory fibers carry sensory recall a specific precipitating traumatic event. The information from the shoulder joint, as well as the skin cervical spinal and the shoulder MR findings were covering the inferior region of the deltoid muscle (1). normal and he has been treated with with anti- Isolated axillary nerve involvement generally appears inflammatory drugs. It was determined that the pain secondary to the trauma and reveals itself through complaints lessened, however there was weakness and limitation of the shoulder movements (2). slimming on the shoulder. Neurological examination revealed muscle strength (Medical Research Council CASE scale) as 3 in shoulder abduction, atrophy of deltoid muscle and hypoesthesia in the area of axillar nerve It has come to the knowledge that a 32 year old male sensory distribution. patient has referred to a physical therapy rehabilitation At the sixth month of the disease onset, nerve 212 Düşünen Adam The Journal of Psychiatry and Neurological Sciences, Volume 26, Number 2, June 2013 Tekin-Guveli B, Aysal F, Gursoy AE, Kolukisa M, Askin S, Hakyemez A, Celebi A Figure 3: Denervation potentials in right deltoid muscle Figure 2: Reinnervation potentials in the right deltoid muscle conduction study (NCS) performed by surface the C5-C6 cervical nerve roots except teres minor and stimulation along the posterior border of the deltoideus muscle confirmed the diagnosis of the sternocleidomastoid muscle and recording from the isolated axillary nerve involvement. deltoid muscle, revealed that right axillary nevre We evaluated ANA, ds DNA, anticardiolipin compound muscle action potential amplitude was antibodies, brucella, syphilis and tumour markers lower compared to the left side (Figure 1). NCSs of the including CEA, AFP, PSA, CA-125 for differential other motor and sensorial nerves showed normal results diagnosis of vasculitis, because it is well known that (Table 1,2). vasculitic neuropathy could manifest with an isolated Needle electromyography (EMG) studies revealed nerve involvement at disease onset and later with reduced recruitment of polyphasic motor unit potentials, mononeuritis multiplex. with prolonged duration and normal and increased Isolated axillary nerve involvement is a rare amplitude in the right deltoid and teres minor muscles condition. Injury to the axillary nerve is most commonly (Figure 2), with resting fibrillation potentials and reported following trauma of the shoulder. Visser et al. positive sharp waves in deltoid muscle (Figure 3). EMG (3) reported axillary nerve involvement in anterior findings regarding the right teres major, biceps, shoulder dislocations as common as 42%. Various brachioradial, suprasinatus, infraspinatus, rhomboideus causes including deep intramuscular injection in the major, serratus anterior, triceps, flexor carpi radialis, deltoid muscle, carrying heavy backpacks and long extensor digitorum communis, first dorsal interosseus duration of general anesthesia at a position have also were all within the normal limits. been described (1). Our patient could not recall a specific precipitating traumatic event. We excluded primary DISCUSSION shoulder disorders including rotator cuff injuries and calcified tendinitis and cervical spinal disorders The reason of the diagnostic delay of our presenting including spondylosis and cervical discopathy with case might be that the isolated axillary nerve involvement normal findings on MR examination. We established is a rarely encountered condition. Because of the low the diagnosis isolated axillary neuropathy as a amplitude of right axillary nerve CMAP, an axonal manifestation of idiopathic acute brachial plexus damage was taken into consideration. Normal findings neuropathy. of median nerve sensory conduction study