Ultrasound-Guided Needle Release Combined with Corticosteroid Injection for the Treatment of Supinator Syndrome

Summary

The deep branch of the radial nerve can easily be compressed at the arcade of Frohse due to its anatomical features. Ultrasound-guided needle release combined with corticosteroid injection is an effective and safe treatment for deep branch radial nerve adhesion.

Abstract

The two main branches of the radial nerve (RN) are the deep branch (DBRN) and the superficial branch (SBRN). The RN splits into two main branches at the elbow. The DBRN runs between the deep and shallow layers of the supinator. The DBRN can be easily compressed at the arcade of Frohse (AF) due to its anatomical features. This work focuses on a 42-year-old male patient who had injured his left forearm 1 month prior. Multiple muscles of the forearm (extensor digitorum, extensor digiti minimi, and extensor carpi ulnaris) were sutured in another hospital. After that, he had dorsiflexion limitations in his left ring and little fingers. The patient was reluctant to undergo another operation because he had undergone suture surgeries for multiple muscles 1 month prior. Ultrasound revealed that the deep branch of the radial nerve (DBRN) had edema and was thickened. The exit point of the DBRN had deeply adhered to the surrounding tissue. To relieve this, ultrasound-guided needle release plus a corticosteroid injection were performed on the DBRN. Nearly 3 months later, the dorsal extension in the patient's ring and little fingers was significantly improved (ring finger: −10°, little finger: −15°). Then, the same treatment was done for the second time. Nearly 1 month after that, the dorsal extension of the ring and the little finger was normal when the joints of the fingers were fully straightened. Ultrasound could evaluate the condition of the DBRN and its relationship with the surrounding tissues. Ultrasound-guided needle release combined with corticosteroid injection is an effective and safe treatment for DBRN adhesion.

Introduction

The radial nerve (RN) splits into two main branches at the elbow level: the deep branch (DBRN) and the superficial branch (SBRN). The DBRN originates from the main trunk of the RN at the level of the lateral epicondyle of the humerus¹. The DBRN curves around the neck of the radius and then goes through under the tendinous arch of the superficial edge of the supinator muscle, which is called the arcade of Frohse². This anatomical site is the most common entrapment site of the DBRN at the forearm^3,4. In some rare cases, the DBRN can be compressed from the entrance ....

Protocol

This study was approved by the ethical and scientific review board of our hospital. Written informed consent was obtained from the patient. All the treatment procedures were performed by personnel with 10 years of experience in musculoskeletal ultrasound intervention. The operator must have good knowledge of musculoskeletal anatomy. The ultrasound machine used here is mentioned in the Table of Materials and has a high-frequency probe.

1. Instrument setup and patient prep.......

Discussion

In recent years, ultrasound has become a valuable tool for assessing peripheral nerve entrapments. Ultrasound can be used to observe nerves in real-time and provide dynamic visualization¹². The obvious sonographic indicator of entrapment is the increased nerve CSA at the site of entrapment^13,14. Other findings such as a hypoechoic texture, nerve flattening, and increased vascularity are also reported in entrapment neuropathy

Materials

Name	Company	Catalog Number	Comments
Betamethasone	MSD Merck Sharp & Dohme AG	B7005-100MG
Injection syringe	Hangzhou Minsheng Pharmaceutical Co., LTD		5 mL and 10 mL
Lidocaine	Shanghai Zhaohui Pharmaceutical Co., LTD	H41022244	7 mL
Sodium chloride	Hangzhou Minsheng Pharmaceutical Co., LTD	http://www.mspharm.com/pro_list.asp?PageNumber=3&info_kind=004001 &d_add_date1=&d_add_date2=& skind=&p_keys=	5 mL
Ultrasonic diagnostic system	SIEMENS		Type:ACUSON Sequoia