Introduction

Medial antebrachial cutaneous nerve (MACN) neuropathy is reported to be caused by iatrogenic reasons. Although the cases describing the posterior branch of MACN neuropathy are abundant, only one case caused by lipoma has been found to describe the anterior branch of MACN neuropathy in the literature. As for the reason for the forearm pain, we report the only case describing isolated anterior branch of MACN neuropathy which has developed due to repeated minor trauma.

Case presentation

We report a 37-year-old woman patient with pain in her medial forearm and elbow following the shaking of a rug. Pain and symptoms of dysestesia in the distribution of the right MACN were found. Electrophysiological examination confirmed the normality of the main nerve trunks of the right upper limb and demonstrated abnormalities of the right MACN when compared with the left side. Sensory action potential (SAP) amplitude on the right anterior branch of the MACN was detected to be lower in proportion to the left. In the light of these findings, NSAI drug and physical therapy was performed. Dysestesia and pain were relieved and no recurrence was observed after a follow-up of 14 months.

Conclusion

MACN neuropathy should be taken into account for the differential diagnosis of the patients with complaints of pain and dysestesia in medial forearm and anteromedial aspect of the elbow.

Introduction

The medial antebrachial cutaneous nerve (MACN) arises from the medial cord (78%) and the lower trunk (22%) of the brachial plexus. It goes along the course of the median and ulnar nerves, vena basilica, and arteria brachialis, in the upper arm [1]. In the literature, causes of MACN neuropathy include iatrogenic reasons such as steroid injection due to medial epicondylitis, routine venipuncture, cubital tunnel surgery, loose body removal, elbow arthroscopy, open fractures fixation, tumour excision, and arthrolysis [2-7]. It is also caused more rarely by repeated minor trauma (from tennis) and soft tissue laceration. It is even more rarely brought about by tuberculoid leprosy neuritis or subcutaneous lipoma [8-10]. However, MACN neuropathy is thought to be noticed less often due to the fact that it causes minor discomfort for the patients and does not affect the hand [10]. Although in some cases where MACN neuropathy was diagnosed, it was not specified which branch of the nerve was affected [3,7,9]. Due to the variety in its anatomic localization, the posterior branch of MACN is inclined to be more vulnerable to iatrogenic causes such as cubital tunnel surgery and direct invasive procedures to the medial part of the elbow [2,4-6,11]. Although the cases in the literature describing neuropathy of the posterior branch of the MACN are abundant [2,4-6] only one case caused by lipoma has been found to describe the anterior branch of the MACN as the site of neuropathy [10]. As for the reason for forearm pain, we report the only case describing isolated neuropathy of the anterior branch of the MACN which has developed due to repeated minor trauma.