Table 1. Etiology and Findings of Electrodiagnosis and Nerve Ultrasound in Patients with Radial or Posterior Interosseous Neuropathy.

Patient #	Etiology	EDX Result	NUS Result
1	Idiopathic	RN	RN + PIN
2	Humerus Fracture	RN	RN + PIN
3	Humerus Fracture	RN	RN + PIN
4	Gunshot Wound	RN	RN + PIN
5	Sleep Compression	RN	RN + PIN
6	Idiopathic	RN	RN + PIN
7	Humerus Fracture	RN	RN
8	Gunshot Wound	RN	RN
9	Gunshot Wound	RN	RN
10	Post- Surgery	RN	RN
11	Tumor	RN	RN
12	Idiopathic	RN	RN
13	Idiopathic	RN	RN
14	Idiopathic	RN	Normal
15	Sleep Compression	RN	Normal
16	Elbow Fracture	PIN	PIN
17	Idiopathic	PIN	PIN
18	Humerus Fracture	Posterior cord	RN
19	Tumor	Normal	RN

Legend: EDx: electrodiagnosis; NUS: nerve ultrasound; RN: radial neuropathy; PIN: posterior interosseous neuropathy. Patients #1-6, in bold, had both radial and posterior interosseous neuropathy identified with nerve ultrasound.