Table 1. Summarizes the relevant literature related to the use of ultrasound in the evaluation of traumatic peripheral nerve injuries.

Author	Study Type	Population	Findings	Comments
Chiou et al. [15]	Review	-	US was successful in showing: • Nerve matter enlargement. • Complete or partial transection. • Nerve laceration. • Epineural hematoma. • Neuroma formation.	• Mechanism of injury ranges from either direct force or transmitted forces applied the nerve matter. • Ultrasound can identifies nerve matter disruption or subsequent neuroma formation of the injured segment.
Peer et al. [26]	Prospective study	• 18 patients • 8 adult men and 10 adult women.	US was successful in showing: • Nerve axonal swelling. • Scar tissue or surgical implant compromising the nerve. • Neuroma. • Insufficient surgical repair.	The lesions detected with ultrasound were consistent with the surgical findings applied in most of the patients.
Lee et al. [28]	Retrospective study	• 13 patients, • Underwent ultrasonographic evaluation and surgical treatment of peripheral nerve lesions	US was successful in showing: • Localize painful postoperative neuromas. • Limit extensive dissections. • Localizing the proximal segment of a radial nerve divided by a humerus fracture.	Ultrasound demonstrated correct lesion diagnosis and location.
Koenig et al. [29]	Prospective study	• 18 Patients. • Aged 17 to 42 years • History of traumatic or iatrogenic lesions of peripheral nerves of the upper and lower extremity	US was successful in showing: • Intra-neural structure with high resolution. • Fascicles passing through a damaged nerve segment may be differentiated from neuromatous tissue more accurately.	Ultrasound represents useful tool for assessment of the internal extent of a nerve lesion and for noninvasive assessment of regenerative potential.
Renna et al. [30]	Case report	• Female patient, • Aged 43 years, • History of sensory digital ulnar nerve injury following surgery.	US was successful in showing: • Very small nerves and their terminal branches.	• Ultrasonography was applied for examination of digital ulnar branch neuromas.
Zhu et al. [32]	Prospective study	• 202 patients. • Aged 17 to 64 • History of traumatic peripheral nerve injury.	US was successful in showing: • Evaluate the type of traumatic injuries. • Monitor the morphological changes in injured nerve, particularly the inner part.	• Ultrasound combined with electrodiagnostic tests provide more data to make a decision about whether or not to precede with surgery.
Padua et al. [33]	Prospective study	• 98 patients. • Aged 8 to79 years. • History of traumatic nerve lesions.	US was successful in showing: • The diagnosis or modify the therapeutic path in 60% of patients. • Nerve injury (neurotmesis/axonotmesis) • The etiology and sites of damage. • The diagnosis where neurophysiological evaluation could not do so. • Useful for surgical planning • Depiction of very small nerves with dynamic imaging.	• Ultrasound was recommended for evaluation in all traumatic patients in whom nerve lesion is suspected
Bodner et al. [35]	Case series	• 4 Adults. • Aged 28 to 62. • Having accessory nerve palsy.	US was successful in showing: • Nerve transection. • Scar tissue. • Atrophy of Trapezius muscle as an indirect indicator of nerve injury.	Posttraumatic accessory nerve palsy was successfully diagnosed with ultrasound. This was confirmed with electro-physiologic testing and surgical exploration.
Cokluk et al. [36]	Prospective study	• 36 patients. • Aged 7 to 57 years. • 30 adults, 6 children.	The patients had various traumatic upper extremity peripheral nerve injuries including: • Ulnar nerve injury. • Radial nerve injury. • Median nerve injury. • Brachial plexus injuries.	• Sonographic observations were compared with the surgical findings. • Use of ultrasound has a role in detecting the early as well as late phase of injury with excellent results.
Cokluk et al. [37]	Prospective study	• 22 patients. • Aged 21 to 52 years.	The patients with traumatic lower extremity peripheral nerve injuries including: • Femoral nerve injury. • Sciatic nerve injury.
Toros et al. [38]	Prospective study	26 patients.	US was successful in showing: • Hypo-echogenicity. • Swelling of the nerve axons. • Transection. • Partial laceration. • Neuroma formation.	• Trauma and/or entrapment of peripheral nerves with resultant Sensory and/or motor neuropathy were evaluated using ultrasound. • Such findings were correlated with the physiological examination and surgical exploration.
Huang et al. [39]	Case report	• Male patient. • Aged 31 years. • Retroperitoneal femoral nerve injury.	US was successful in showing: • Femoral nerve lesion at the retroperitonium. • Determination of swelling of the nerve. • Identification of neuroma formation.	• Ultrasound proposed to be used to make early decision in clinical treatment for a better recovery.
Cartwright et al. [40]	Case report	• Adult Male, • Aged 36 years • History of shot in the right arm	• Site of the fracture was over the nerve, which was difficult to visualize by US. • Nerve segments proximal and distal to fracture site were aligned.	• Ultrasound proposed the radial nerve was anatomically intact and therefore conservative management was used rather than surgical intervention.
Kwak et al. [41]	Retrospective study	• 8 patients. • Aged 36 to 69 years.	Incidental detection of traumatic neuromas with history of neck dissection or painful Fine needle aspiration.	• Asymptomatic patients were incidentally diagnosed to have neuroma. • Ultrasound showed iso-echoic mass with associated internal parallel heterogeneous hyper-echogenicity.
Lee et al. [42]	Retrospective study	• 24 paediatric patients • Aged 6 to 12 years. • History of closed upper limb injuries and associated peripheral nerve palsy.	US was successful in showing: • Pathomorphologic information. • Reduce the morbidity involved in nerve explorations	• Ultrasound findings correlated with intraoperative findings and clinical recovery
Filippou et al. [43]	Prospective study	91 patients.	US was successful in showing: • Subluxation of the ulnar nerve • Luxation of the ulnar nerve • Presence of osteophytes • Presence of accessory muscle • Articular ganglion • Post-traumatic lesions • Presence of osseous fragments	• Ulnar neuropathy; can be caused by multiple aetiologies involving posttraumatic changes such as bone fragments. • Ultrasound imaging of the affected joint has a significant role in detecting such changes.
Ng et al. [44]	Retrospective study	• 42 patients. • History of ulnar neuropathy at the elbow.	US was successful in showing: • Ulnar neuropathy at the elbow. • Localize anatomical details such as nerve continuity. • Diagnose and characterize lesions outside the elbow region	• Ultrasound can diagnose and characterize lesions outside the elbow region.
Bodner et al. [46]	Case report	• Adult male patient. • Fractured humerus.	• Entrapment of Radial nerve within fracture site. • Abrupt change in the surface of radial nerve was seen.	• The technique involved identification of radial nerve at the distal trauma free part of the humerus in both a transverse and longitudinal scans and followed proximally to the site of injury.
Bodner et al. [47]	Prospective study	• 11 Patients. • Aged 10 to 72 years. • History of radial nerve palsy following fractured humerus.	US confirmed radial nerve injury, and showed: • Nerve entrapment between bony fragments. • Complete nerve dissection. • Nerve laceration. • Nerve riding on the edges of bony fragments. • Nerve buried in callus.