Eric J Super, Marin S Smith, Matthew E Miller, Jay Smith, Xiaoning Yuan
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引用次数: 0
Abstract
Objectives: Carpal tunnel syndrome (CTS) is the most common peripheral entrapment neuropathy. Anatomic variations of the median nerve (MN) and carpal tunnel (CT) may predispose patients to CTS or increase procedural complexity and risk during carpal tunnel release (CTR). This study aimed to systematically evaluate the prevalence of 25 MN and CT anatomic variations and measurements using ultrasound (US) in patients referred for electrodiagnostic testing (EDX).
Methods: In this cross-sectional observational study, patients underwent diagnostic US exams of the MN (mid-brachium to distal CT), focused on variant anatomy that may predispose to CTS (bifid MN, Gantzer's muscle, lumbrical intrusion) or increase procedural complexity/risk (transligamentous thenar motor branches [TMBs], MN orientation ulnar to the palmaris longus [PL] tendon).
Results: Two hundred and twenty patients (mean age: 45.3 ± 13.0 years; 63.6% male; 294 UEs) were evaluated by US. Hundred and eight UEs met EDX criteria for CTS (EDX-CTS). The most common variations identified were lumbrical intrusion (81.3%), Gantzer's muscle (39.5%), and persistent median artery (22.8%), which were not associated with EDX-CTS. US revealed transligamentous (2.4%) and ulnar origin (4.5%) TMBs, which may increase injury risk during CTR. MN location was ulnar to the PL tendon in 70.4% of wrists, which can predispose to injury during landmark-guided CT injections.
Conclusions: This study demonstrated that US complements EDX and can systematically identify anatomic variations, including variants at risk during CTS interventions. No differences in the prevalence of variations were detected between patients with and without EDX-CTS. Diagnostic US can support procedural planning, improve safety, and lower injury risk.
期刊介绍:
The Journal of Ultrasound in Medicine (JUM) is dedicated to the rapid, accurate publication of original articles dealing with all aspects of medical ultrasound, particularly its direct application to patient care but also relevant basic science, advances in instrumentation, and biological effects. The journal is an official publication of the American Institute of Ultrasound in Medicine and publishes articles in a variety of categories, including Original Research papers, Review Articles, Pictorial Essays, Technical Innovations, Case Series, Letters to the Editor, and more, from an international bevy of countries in a continual effort to showcase and promote advances in the ultrasound community.
Represented through these efforts are a wide variety of disciplines of ultrasound, including, but not limited to:
-Basic Science-
Breast Ultrasound-
Contrast-Enhanced Ultrasound-
Dermatology-
Echocardiography-
Elastography-
Emergency Medicine-
Fetal Echocardiography-
Gastrointestinal Ultrasound-
General and Abdominal Ultrasound-
Genitourinary Ultrasound-
Gynecologic Ultrasound-
Head and Neck Ultrasound-
High Frequency Clinical and Preclinical Imaging-
Interventional-Intraoperative Ultrasound-
Musculoskeletal Ultrasound-
Neurosonology-
Obstetric Ultrasound-
Ophthalmologic Ultrasound-
Pediatric Ultrasound-
Point-of-Care Ultrasound-
Public Policy-
Superficial Structures-
Therapeutic Ultrasound-
Ultrasound Education-
Ultrasound in Global Health-
Urologic Ultrasound-
Vascular Ultrasound