Role of dynamic ultrasound in assessment of the snapping elbow and distal biceps tendon injury

Abstract

Introduction Ultrasound is useful in assessing patients with snapping syndromes around the elbow joint. The dynamic nature of the examination allows for direct visualisation of the underlying causative factor. Topic description: We discuss the role of dynamic ultrasound in assessing various snapping syndromes around the elbow, such as ulnar nerve instability, snapping triceps and less commonly, snapping brachialis. Ultrasound is also useful in evaluating the distal biceps tendon, particularly in differentiating partial from complete tendon injury. Discussion Ulnar nerve instability and snapping triceps can be assessed via a medial approach with the transducer placed transversely between the medial epicondyle and the olecranon. In ulnar nerve instability, the nerve can be seen crossing over the medial epicondyle on elbow flexion. In snapping triceps syndrome, both the ulnar nerve and the distal triceps can be seen dislocating over the medial epicondyle. Dynamic assessment of the distal biceps tendon using a lateral approach minimises anisotropy artefact often seen on the anterior approach. Passive pronation and supination of the forearm will reveal little or no movement in a completely torn tendon whereas moving tendon fibres will be appreciated in partial tears. In a snapping brachialis, the medial portion of brachialis will be seen abnormally translocating anterolateral to the medial border of the trochlea during elbow flexion and snapping back into its normal position on elbow extension. Conclusion Dynamic ultrasound of the elbow is valuable in diagnosing patients with snapping sensations around the joint and in evaluating the integrity of the distal biceps tendon.

Hearing and Seeing Nerve/Tendon Snapping: A Systematic Review on Dynamic Ultrasound Examination

“…The agreement between the authors for including the articles was perfect (Cohen’s k = 0.87). The main characteristics of the studies (published between 1983 and 2023) are summarized in Table 1 for nerves [ 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 ] and in Table 2 for tendons [ 1 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 ,…”

“…The 40 papers reviewed for nerves comprised 16 original articles, 6 reviews, 14 case reports, 3 retrospective studies and 2 letters to the editor [ 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 ]. Similarly, 49 papers reviewed for tendons comprised 7 original articles, 17 reviews, 23 case reports/series and 1 retrospective study [ 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 ,…”

Multimodality imaging review of ulnar nerve pathologies

“…24,25 Another advantage of ultrasound is its ability to provide useful real-time images assessing the dynamic evaluation of the ulnar nerve during flexion and extension maneuvers of the elbow. 26 MRI is superior to ultrasound in the evaluation of complex and deeper structures like the brachial plexus in addition to the characterization of lesions secondary to improved soft tissue differentiation and simultaneous evaluation of denervated muscles. Magnetic resonance neurography (MRN) is an advanced imaging technique specifically designed for the optimal evaluation of peripheral nerves using a high strength magnet, phase array coils, better gradient performance, wider bandwidths, and spin echo technique to produce high spatial resolution, high contrast resolution, and thinner slice images.…”

“…24,25 Another advantage of ultrasound is its ability to provide useful real-time images assessing the dynamic evaluation of the ulnar nerve during flexion and extension maneuvers of the elbow. 26…”

Snapping of the Upper Limb: a Clinical Overview

“…MRI of the elbow in various flexion positions may effectively demonstrate the dislocation of the anatomical structures involved in snapping. Dynamic ultrasound is often used as it allows real-time visualization of the underlying pathology (42). Conservative treatment is initiated at first and consists in stopping at risk-activities, a course of non-steroidal anti-inflammatory drugs, a brace limiting elbow flexion to 70° and Arthroscopic/open resection corticosteroid injections.…”