Traumatic Finger Injuries: What the Orthopedic Surgeon Wants to Know

Abstract

Traumatic finger injuries account for a substantial number of emergency visits every year. Imaging plays an important role in diagnosis and in directing management of these injuries. Although many injuries can be managed conservatively, some require more invasive interventions to prevent complications and loss of function. Accurate diagnosis of finger injuries can often be difficult, given the complicated soft-tissue anatomy of the hand and the diverse spectrum of injuries that can occur. To best serve the patient and the treating physician, radiologists must have a working knowledge of finger anatomy, the wide array of injury patterns that can occur, the characteristic imaging findings of different finger injuries, and the most appropriate treatment options for each type of injury. This article details the intricate anatomy of the hand as it relates to common finger injuries, illustrates the imaging findings of a range of injuries, presents optimal imaging modalities and imaging parameters for the diagnosis of different injury types, and addresses which findings have important management implications for the patient and the orthopedic surgeon. With this fund of knowledge, radiologists will be able to recommend the most appropriate imaging studies, make accurate diagnoses, convey clinically relevant imaging findings to the referring physician, and suggest appropriate follow-up examinations. In this way, the radiologist will help improve patient care and outcomes. Online supplemental material is available for this article. (©)RSNA, 2016.

Ultrasound of flexor digitorum apparatus in acute and chronic pathology

“…Traumatic finger injuries are common, accounting for approximately 20% of patients presenting to the emergency department . Injuries range from superficial lacerations to more serious injuries involving penetration of the tendon(s).…”

“…and Verdan classified tendon injuries into five anatomic zones: Zone I extends from the insertion of the FDS to the insertion of the FDP. Zone II extends from the A1 pulley to the distal insertion of the FDS. Zone III extends from the distal flexor retinaculum of the carpal tunnel to the proximal part of the A1 pulley and contains the lumbrical origins from the FDP tendons. Zone IV is composed of the flexor tendons within the carpal tunnel. Zone V is composed of the forearm proximal to the carpal tunnel. Zone I laceration will result in loss of DIP flexion caused by injury to the FDP tendon. Laceration occurring in zones II–V will result in loss of both DIP and PIP joint flexion as they involve injuries to both FDP and FDS . Lacerations in zone II are the most common, usually affecting the mid‐substance of the tendon rather than the distal insertion .…”

“…Zone II injuries have the most pessimistic prognosis because of the frequency of complications including adhesions, entrapment or triggering of the flexor tendons from scar formation under the A2 pulley. When an injury to zone II occurs early surgical exploration is often required to avoid functional impairment of the hand . Ultrasound is able to differentiate between partial and complete laceration defining the extent of the laceration utilising LAX imaging and axial imaging for confirmation.…”

“…Flexor tendon ruptures result in a greater degree in retraction compared with extensor tendon ruptures as the extensor system anatomy is imbedded with robust connection fibres preventing retraction …”

Emergency and Trauma of Hand and Wrist

“…6 The traumatic injuries range from obvious to very subtle; however, even subtle injuries can alter hand function significantly and affect performance. 7,8 Early detection will help prevent long-term complications and allow the patient to get appropriate and timely treatment and a quick return to play or work. 8,9 When dealing with acute hand and wrist trauma as an musculoskeletal radiologist, several challenges arise in the process of diagnosis and guiding the clinician.…”