The use of ultrasound for monitoring reduction and ulnar nerve subluxation in pediatric humeral supracondylar fractures

Chien-An Shih; Ming-Tung Huang; Tai-Chang Chern; Chung-Jung Shao; Kuo-Chen Wu; Chii-Jeng Lin; I-Ming Jou; Po-Ting Wu

doi:10.1016/j.ejrad.2023.111201

The use of ultrasound for monitoring reduction and ulnar nerve subluxation in pediatric humeral supracondylar fractures

Eur J Radiol. 2024 Jan:170:111201. doi: 10.1016/j.ejrad.2023.111201. Epub 2023 Nov 14.

Authors

Chien-An Shih¹, Ming-Tung Huang², Tai-Chang Chern³, Chung-Jung Shao⁴, Kuo-Chen Wu⁵, Chii-Jeng Lin⁶, I-Ming Jou⁷, Po-Ting Wu⁸

Affiliations

¹ Department of Orthopedics, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
² Department of Orthopedics, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan; Great East Gate Orthopedic Clinic, Tainan, Taiwan.
³ Chern Tai-Chang's Orthopedic Clinic, Ping-Tong, Taiwan.
⁴ Department of Orthopedic Surgery, Tainan Municipal Hospital, Tainan, Taiwan.
⁵ Department of Orthopedic Surgery, Kuo General Hospital, Tainan, Taiwan.
⁶ Department of Orthopedics, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan; Department of Orthopedics, College of Medicine, National Cheng Kung University, Tainan, Taiwan; President Office, Joint Commission of Taiwan, New Taipei City, Taiwan, ROC.
⁷ Great East Gate Orthopedic Clinic, Tainan, Taiwan; Department of Orthopedics, E-Da Hospital, Kaohsiung, Taiwan; School of Medicine, College of Medicine, I-Shou University, Kaohsiung, Taiwan. Electronic address: ed109325@edah.org.tw.
⁸ Department of Orthopedics, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan; Department of Orthopedics, College of Medicine, National Cheng Kung University, Tainan, Taiwan; Department of Biomedical Engineering, National Cheng Kung University, Tainan, Taiwan; Department of Biochemistry and Molecular Biology, College of Medicine, National Cheng Kung University, Tainan, Taiwan; Medical Device Innovation Center, National Cheng Kung University, Tainan, Taiwan. Electronic address: anotherme500@gmail.com.

PMID: 38042022
DOI: 10.1016/j.ejrad.2023.111201

Abstract

Background: Traditional treatment for displaced humeral supracondylar fractures (SCFs) in children involves closed reduction (CR) under fluoroscopic guidance, percutaneous pinning, and immobilization with a long-arm cast. This study aims to explore the viability of using radiation-free ultrasound (US) for guiding CR and tracking ulnar nerve dynamics during medial pinning, contrasting the US method with the conventional cross pinning technique.

Materials and methods: We assessed 70 children with acute displaced SCFs. The US group (n = 30) underwent US-guided reduction, whereas the traditional group (n = 40) underwent fluoroscopy-guided reduction. Both groups received percutaneous cross pinning and subsequent cast immobilization. Postoperative outcomes were compared between the two methods after a 6-month follow-up. In the US group, ultrasonography assessed fracture displacement distances before and after CR. The angle at which the ulnar nerve relocated to the cubital tunnel during elbow extension was documented using real-time US monitoring during medial pinning.

Results: The US group demonstrated improved reduction accuracy, increased range of motion, superior restoration of both Baumann and Humeroulnar angles, and a decreased incidence of malunions compared to the traditional group (all p < 0.05). The ultrasonographic measurement of fracture displacement was comparable with that of fluoroscopy (intraclass correlation coefficient > 0.90). In the US group, no ulnar nerve injury was noted, compared to 2.5 % in the traditional group, and real-time US observations revealed ulnar nerve hypermobility, with 53.3 % of patients exhibiting anterior ulnar nerve subluxation at 120° elbow flexion, 40 % at 90°, 16.7 % at 60°, and none at 30° flexion.

Conclusion: Ultrasound is as reliable as fluoroscopy for evaluating fracture reductions. The use of intra-operative ultrasound significantly improves reduction accuracy and radiographic outcomes while reducing the risk of ulnar nerve injury.

Keywords: Fracture reduction; Humeral supracondylar fracture; Iatrogenic ulnar nerve injury; Ulnar nerve subluxation; Ultrasound.

MeSH terms

Bone Nails
Child
Fracture Fixation, Internal / methods
Humans
Humeral Fractures* / diagnostic imaging
Humeral Fractures* / surgery
Humerus
Joint Dislocations*
Retrospective Studies
Treatment Outcome
Ulnar Nerve / diagnostic imaging
Ultrasonography