Fig. 2
From: An overview of neuromuscular ultrasound of important small nerves
Examples of palmar cutaneous nerve pathologies. A, B Short-axis views of the palmar cutaneous nerve in a patient who complained of pain and numbness along the right palm post-carpal tunnel surgery. A shows a normal sonographic appearance of the palmar cutaneous branch as it pierces the deep brachial fascia. B The PCN after it penetrates the fascia where it appears surrounded by hypoechoic tissue representing scar tissue encasing the nerve with thickening of the nerve epineurium. C, D Short-axis views of the palmar cutaneous nerve in a patient who complained of numbness at the lateral palm and severe pain on touch at the wrist post-carpal tunnel release. C Normal sonographic appearance of the palmar cutaneous branch (arrow) as it runs deep the antebrachial fascia. D Abrupt hypoechoic swelling of the PCN nerve after it pierces the fascia as it runs medial to the FCR tendon representing neuroma-in-continuity