MR imaging of ligament and tendon injuries of the fingers

Tendon and ligament injuries of the finger and thumb in athletes: a narrative review

Acute finger and thumb injuries of the ligament and tendons are common. Indeed, a cross-sectional study in 2012 showed that they accounted for 38.4% of all upper extremity injury visits to the emergency room in the USA. Understanding the anatomy and mechanical functions of tendons and ligaments in the digits is crucial for recognising various types of injuries and their treatment. Treating an athlete with such conditions comes with the added pressure of ensuring a timely return to play. This review will cover the anatomy, diagnoses and management of select tendinous and ligamentous injuries of the fingers and thumb seen in athletes.

Imaging of Sport-related Finger Injuries

Traumatic finger injuries in athletes are widespread and vary widely, from minor sprains to complex fractures or tendon damage, with occurrences differing by sport due to distinct biomechanical demands. Imaging plays a pivotal role in assessing these injuries. Radiography serves as the primary diagnostic tool, crucial for detecting bone-related abnormalities; ultrasound and magnetic resonance imaging are essential for evaluating soft tissue injuries. Prompt and accurate diagnosis is key to ensuring effective treatment and preventing long-term complications, thereby facilitating a quick and safe return to sports activities.

MRI Diagnostics of the Fingers: Current Developments and Clinical Relevance

Magnetic resonance imaging (MRI) is an excellent method for visualizing the complex anatomical structures of the fingers. The high diagnostic standard is based on numerous recent technical developments to improve soft tissue differentiation and detail recognition, and includes time-resolved functional imagingThis review highlights the current status of MRI in finger diagnostics. The content of this narrative review is based on a literature search in the PubMed and Google Scholar databases using the search terms "finger MRI" and "finger imaging".Due to numerous technical optimizations and the increasing clinical availability of MRI, this examination has become indispensable in routine use for the further clarification of traumatic and orthopedic clinical pictures. MRI is also playing an increasingly important role in rheumatic and inflammatory issues, as well as tumors, whereby the particularly high potential for early detection and the detailed soft tissue imaging are especially advantageous. · MRI enables precise differential diagnosis of all clinical pictures of the fingers and is useful in the clarification of traumatic, orthopedic, rheumatic, inflammatory, and neoplastic issues.. · Multi-channel hand coils, scanners with high magnetic field strengths, and the use of contrast agents have led to an evaluation with resolutions in the submillimeter range in some cases.. · High-resolution MRI, including the possibility of functional examination, makes it easier to determine adequate therapy and avoid subsequent damage while meeting high standards.. · Bayer T, Lutter C, Janka R et al. MRI Diagnostics of the Fingers: Current Developments and Clinical Relevance. Rofo 2025; DOI 10.1055/a-2594-7451.

MRI findings of closed hand injuries in adolescent goalkeepers: a case-based review

Soccer-related injuries in youth goalkeepers are underrepresented in epidemiological studies, despite goalkeepers experiencing distinct types of upper limb injuries and training loads compared to outfield players. Digit injuries are particularly prevalent, with up to five times more upper extremity injuries reported in this position. Such injuries can lead to interphalangeal joint instability and an increased risk of reinjury. Mechanisms of injury include falls, axial loading of digits, and rotational force due to grasping activities. The proximal interphalangeal joint is the most frequently injured in sports, followed by the metacarpophalangeal joint of the thumb. Achieving precise diagnosis can be challenging due to the complex soft-tissue anatomy of the hand. Radiologists play a crucial role in accurate diagnosis through imaging studies, enabling timely treatment. This article focuses on closed traumatic finger and thumb injuries in adolescent goalkeepers, describing injury mechanisms and outlining relevant MRI features to facilitate proper clinical approaches for diagnosis based on imaging findings.

MRI spectrum of injuries to the thumb metacarpophalangeal joint ulnar collateral ligament with a proposed expanded classification of injuries in American football players

Injuries to the ulnar collateral ligament of the thumb metacarpophalangeal joint are of both historic and modern interest for athletes and non-athletes alike. The thumb metacarpophalangeal joint requires stability in both flexion and extension utilizing a combination of static and dynamic stabilizers. This article reviews the magnetic resonance imaging categorization of thumb ulnar collateral ligament injuries and proposes two additional injury patterns seen in high-level and professional athletes who play American football. In addition to the direct magnetic resonance imaging findings in collateral ligament tears, secondary findings of rotation and subluxation can be seen at the thumb metacarpophalangeal joint due to the altered physiologic forces on the joint. Internal brace augmentation via suture tape of a traditional ulnar collateral ligament repair is a novel surgical technique that provides protection during initial healing and the ensuing remodeling phase following repair or reconstruction, resulting in a faster return to play.

High-Resolution Finger MRI: What Should You Look for in Trauma of the Fingers?

The fingers are among the most commonly injured structures in traumatic injuries resulting from sports and work. Finger injuries encompass a broad spectrum of injuries to bone and soft tissues, including tendons, ligaments, and cartilage. The high resolution of 3T MRI with dedicated surface coils allows for optimal assessment of the intricate soft tissue structures of the fingers. There have been several reports on detailed MRI features of the basic anatomy and common pathological findings of the finger and hand. Understanding the normal anatomy and familiarization with common traumatic lesions of the ligaments, tendons, and pulleys of the fingers on high-resolution MRI will allow radiologists to perform accurate preoperative evaluations of traumatic hand lesions. The purpose of this study is to review the normal hand anatomy and common traumatic lesions of the finger on high-resolution MRI and correlate them with surgical findings.

MRI anatomy and injuries of the fingers

Magnetic resonance imaging (MRI) diagnosis of underlying finger pathology can be intimidating due to the presence of unique anatomy. The small size of the fingers and the unique orientation of the thumb compared to the fingers also introduce unique demands on the MRI system and the technologists performing the study. This article will review the anatomy pertinent to injuries at the fingers, provide protocol guidance, and discuss pathology encountered at the fingers. Although much of the encountered pathology in the fingers overlaps with adults, unique pathology to children will be highlighted when applicable.

An in-depth look at zone III and IV anatomy of the finger extensor mechanism and some clinical implications for use of the relative motion flexion orthosis

BACKGROUND

For hand therapists and hand surgeons acute and chronic injuries of the extensor mechanism (EM) in zones III-IV are challenging to treat with satisfying results.

INTRODUCTION

Early active motion combined with relative motion flexion (RMF) orthoses to manage EM zone III injuries and boutonnière deformity has renewed interest in the complex anatomy and biomechanics of the EM.

PURPOSE

To provide an in-depth discussion of EM zones III-IV anatomy with emphasis on inter-tendinous structures, often omitted in simplified, model-wise illustrations which focus mostly on the tendinous structures.

METHOD

In collaboration the authors combined on the one hand extensive clinical experience and knowledge of the EM literature and on the other hand decades of anatomical, biomechanical and kinesiology research of the EM with special interest for the spiral fibers, through gross anatomy and microdissection anatomy laboratory work, MRI and ultrasonography studies.

RESULTS

The inter-tendinous tissues (i.e., spiral fibers) in zone III are of imminent importance for proper functioning of the EM and to prevent boutonnière deformity to develop after EM surgery or injury.

DISCUSSION

Inter-tendinous links between the tendinous structures of the EM are necessary for balanced finger motion. The spiral fibers are described in more detail because of their role in controlling volar migration of the conjoined lateral bands and because their disruption makes development of boutonnière deformity more likely. Understanding the anatomy and biomechanics of the EM may assist in progress toward 'proof of concept' for use of RMF orthoses and controlled early active motion after EM injury or surgery.

CONCLUSION

Hand surgery and hand therapy practice interventions, including use of RMF orthoses for management of non-surgical and surgical EM injuries may benefit from an in-depth look at the EM zone III and IV anatomy and biomechanics.

[Sports-related injuries of the thumb and fingers]

Finger and thumb injuries are common in established and trend sports. Imaging plays an important role in acute trauma care, further therapy planning, and ultimately for a rapid return to play. Sound knowledge of the complex anatomy of the fingers and thumb is indispensable for accurate diagnosis. This article presents the ligament anatomy of the metacarpophalangeal and interphalangeal joints of the finger and the thumb, the extensor and flexor tendon apparatus, and the diagnosis of typical sports injuries using x‑rays and magnetic resonance imaging. Furthermore, imaging findings of typical sports-associated injuries are illustrated.

The Accuracy and Cost-Effectiveness of MRI Assessment of Collateral Ligament Injuries of the Lesser Digits’ Proximal Interphalangeal Joints

Background

Collateral ligament injuries of the thumb and lesser digits are simple injuries, but they may lead to disabilities in hand function. This study aimed to evaluate the accuracy and cost-effectiveness of magnetic resonance imaging (MRI) in diagnosing proximal interphalangeal (PIP) collateral ligament injuries of lesser digits.

Methods

A retrospective evaluation was conducted on 18 fingers that had undergone surgery for PIP joint complete collateral ligament injury. Pre-operative MRI results were compared with the intra-operative findings. The data from MRI and direct intraoperative findings were analyzed by the Chi-square test in paired groups. The McNemar test analyzed the accuracy of the MRI test for detecting volar plate injuries. Statistical Packages for Social Sciences (SPSS) version 25 (IBM Inc., Armonk, New York) software program was used for the analysis. 

Results

In digits other than the thumb, the accuracy of MRI for detecting collateral injuries was 38.89%, and detection was incorrect in 11 (61.11%) of 18 patients. There are significant differences between MRI and Intraoperative results (p<0.001). MRI findings for seven fingers (38.89%) of the 18 fingers involved were compatible with the surgery results (38.88%). By comparison, the MRI findings of 11 fingers (61.11%) were inconsistent with the intra-operative results. Eight patients (44.44%) were diagnosed preoperatively with MRI as having volar plate ruptures, three patients (16.67%) were diagnosed with open surgery, but only three of the volar plate diagnosed patients with MRI were verified as ruptures during open surgery (38.0%). In addition, preoperatively undetected volar plate injuries by MRI (n=10) were detected intra-operatively in three cases (30.0%). Therefore, the accuracy of MRI was found not to be statistically significant for the detection of volar plate injuries (p=0.727).

Conclusion

This study concluded that a 1.5-Tesla MRI with a slice thickness of 2-3 mm should not be relied on as a decisive tool for diagnosing collateral ligament injuries of the PIP joint of the lesser digits. Additionally, MRI was found insufficient for diagnosing volar plate injuries that accompanied collateral ligament injuries. Given these findings, one might conclude that MRI is not cost-effective in diagnosing collateral ligament injuries of the lesser digits PIP joint.

Pediatric hand ultrasound: common indications, injury, inflammation and masses

Ultrasound is a uniquely valuable tool for evaluating musculoskeletal problems in the pediatric hand. Acute and chronic injuries involving tendons and ligaments of the hand can be quickly assessed and can guide surgical decision-making. Using ultrasound, palpable lesions and masses can be evaluated for cystic and solid components aiding in differential diagnosis. Additionally, ultrasound provides evaluation of acute versus chronic changes of inflammatory arthritis, assessing disease severity and subclinical synovitis and serving as an adjunct to medical management. This review will cover common indications and ultrasound findings of the pediatric hand, focusing on common injuries, inflammatory arthritis and masses. Important anatomical features of the hand will be discussed as well as imaging technique and evaluation in the pediatric patient.

Tendons and Tendon Sheaths of the Hand - An Update on MRI

BACKGROUND

 The tendons of the hand run in close proximity to each other and within retinacular tunnels adjacent to articular joints, while forming intersections in characteristic locations. The enclosing tendon sheaths are often sites of systemic or infectious inflammation.

METHOD

 This review article outlines the different entities of tendon and tendon sheath pathology and their manifestation in the hands. Diagnostic findings in tendon and tendon sheath disorders are illustrated using MRI imaging and discussed in context with the current literature.

RESULTS AND CONCLUSION

 Overuse may cause stenosis in the fibrous outer layer of the retinacula and the A1 annular ligaments as well as tendinosis. In contrast, proliferative tenosynovitis is a disease of the synovial inner layer of the tendon sheath with tendon infiltration and tendinitis. Pyogenic tenosynovitis favors the flexor compartments. Because of the narrow spaces in the hand, a high-resolution MRI technique must be used.

KEY POINTS

  · Diseases of the tendons and tendon sheaths may have a mechanical, degenerative, metabolic, systemic inflammatory, or infectious etiology.. · Fibrous tunnels and bony prominences in close proximity to crossing tendons predispose to mechanical tendon irritation at typical sites of the hand.. · Stenosing tenovaginitis occurs in the fibrous layer of the extensor retinaculum or the A1 annular pulleys. The most frequent manifestations are the "trigger finger" and de Quervain disease.. · Proliferative tenosynovitis affects the synovial layer of the tendon sheaths before infiltrating the tendons. The classic representative is rheumatoid arthritis..

CITATION FORMAT

· Schmitt R, Hesse N, Grunz JP. Tendons and Tendon Sheaths of the Hand - An Update on MRI. Fortschr Röntgenstr 2022; DOI: 10.1055/a-1826-1007.

Biomechanical analysis of the effect of the finger extensor mechanism on hand grasping performance

Quantifying the effect of routing and topology of the inter-connected finger extensor mechanism on hand grasping performances is a long-standing research problem for the better clinical diagnosis, surgical planning and biomimetic hand development. However, it is technically demanding to measure the hand performance parameters such as the contact forces and contact area during hand manipulation. It is also difficult to replicate human hand performance through the physical hand model due to its sophisticated musculotendinous structure. In this study, an experimental validated subject-specific finite element (FE) human hand model was used for the first time to quantify the influence of different tendon topologies and material properties on hand grasping quality. It is found that the grasping quality is reduced by 15.94% and 8.54% if there are no extensor hood and lateral band respectively, and the former plays a more important role in transmitting forces and maintaining grasping qualities than the latter. Excluding extensor hood in the topology causes more reductions in hand contact pressure and contact area than omitting lateral band. 7.5% of the grasping quality is lost due to a softened tendon with half of its original Young's Modulus. Hardened extensor tendon does increase the grasping quality, but the enhancing effect tends to level off once the tendon Young's Modulus is increased by more than 50%. These results prove that the lateral band and extensor hood are critical components for maintaining grasping quality. The dexterity and grasping quality of robotic and prosthetic hands could be improved by integrating these two components. There is also no need to use very stiff tendon material as it won't help to effectively enhance the grasping quality.

Wrist and Hand Trauma Imaging

Injuries to the wrist and hands occur frequently in athletes from the high forces applied during sporting events. The examples presented illustrate the important role imaging has in the diagnosis of wrist and hand injuries. In addition, different imaging modalities are complementary and various examinations may be needed to help guide the management of wrist and hand traumatic pathology.

MRI of Finger Pulleys at 7T-Direct Characterization of Pulley Ruptures in an Ex Vivo Model

The aim of this study was to evaluate 7 Tesla (7T) magnetic resonance imaging (MRI) for direct visualization and specific characterization of the finger flexor pulleys A2, A3, and A4 before and after ex vivo pulley rupture. Thirty fingers of human cadavers were examined before and after pulley disruption with a 26 min clinical 7T pulse sequence protocol. Images were assessed by two experienced radiologists for the presence of pulley rupture. Injury characterization included definition of rupture location, morphology, and complications. Image quality was evaluated according to a 4-point Likert-type scale from “not evaluable” to “excellent”. Macroscopic preparations were used as the reference standard. Direct characterization of intact A2, A3, and A4 pulleys and the corresponding pulley lesions was possible in all cases. The rupture location was distributed equally at the radial, ulnar, and central parts of the pulleys. A dislocation and intercalation of the pulley stump between the flexor tendon and finger phalanges was observed as a complication in 62.5% of cases. The average Likert score for direct visualization of pulleys was 2.67 before rupture and 2.79 after rupture creation, demonstrating adequate image quality for routine application. 7T MRI enables a direct characterization of A2, A3, and A4 pulleys before and after artificial disruption, including the definition of rupture morphology and location as well as the detection of rupture complications. This promises a precise presurgical evaluation of pulley injuries and complicated pulley stump dislocations.

Pulley, Flexor, and Extensor Tendon Injuries of the Hand

Tendon injuries represent the second most common injury of the hand (after fractures) and are a common scanning indication in radiology. Pulley injuries are very frequent in rock climbers with the A2 pulley the most commonly affected. Tendon and pulley injuries can be reliably evaluated using ultrasound (US) and magnetic resonance imaging (MRI). US can be postulated as a first-line imaging modality, allowing dynamic examination. MRI is essential for cases with ongoing diagnostic doubt post-US and also for preoperative pulley reconstruction assessment.

Degenerative lesion of the extensor tendon V finger: Ultrasound imaging in diagnosis and therapeutic possibilities

Traumatic injuries of the extensor tendons of the hand are common and are more frequent predisposed to tendon injuries due to the presence of chronic tendon damage. We present the case of a 61-year-old woman, tailor by profession, who showed acute rupture (80 %) with degenerative etiology of the extensor tendon of the V finger of the fifth level according to Kleinert and Verdan classification.

[Finger injuries with a focus on ligamentous structures]

BACKGROUND

Ligamentous lesions of the fingers are common everyday injuries and usually the result of distortion or overloading. Numerous examination methods are available for dedicated radiological diagnosis of sometimes complex injury patterns.

OBJECTIVES

To review radiological diagnosis of the ligamentous structures of the finger joints including the presentation of anatomical, biomechanical and therapeutic aspects.

MATERIALS AND METHODS

Presentation of the anatomy and biomechanics as well as the most common trauma mechanisms of the ligamentous structures. Review of the literature, discussion of recent work and diagnostic expert recommendations.

RESULTS

The most relevant ligamentous structures are collateral ligaments, pulley ligaments, volar plates and tendons. The goal of radiologic diagnosis is to accurately define the injury pattern and to differentiate between simple and complicated ligamentous lesions. In unclear cases, magnetic resonance imaging (MRI) has become standard for further diagnostics, which may allow depiction of ligamentous structures in submillimetre resolution.

CONCLUSIONS

Today, differential diagnosis includes all radiological modalities, which ensures the determination of an adequate therapy and prevention of sequel at a high standard.

Magnetic resonance imaging of the wrist and hand

The anatomy of the wrist and hand is complex and contains numerous small structures. Magnetic resonance imaging (MRI) is often an ideal imaging modality in the assessment of various traumatic and pathologic conditions of this region, and it is frequently performed after initial radiographs. In this manuscript we describe the normal anatomy, imaging techniques, and MRI findings of various traumatic and pathologic conditions of the wrist and hand including occult fractures, osteonecrosis, ligamentous and tendon injuries, and entrapment neuropathies.

Imaging of the Hand and Wrist

Imaging plays a key role in the evaluation and treatment planning of hand and wrist injuries in athletes. Depending on the suspected injury, a combination of conventional radiographs, computed tomography, magnetic resonance imaging, magnetic resonance arthrography, and/or ultrasound may be indicated. This article reviews the strengths and limitations of these imaging modalities and how they can be utilized in commonly encountered clinical questions.

Semi-dynamic MRI of climbing-associated injuries of the finger

OBJECTIVE

Injuries of the flexor-tendon-pulley system are common in rock climbers. The status of the A3 pulley ligament is crucial for grading such injuries. As standard MRI may miss lesions of the A3 pulley ligament, we introduce a semi-dynamic MRI sequence.

MATERIALS AND METHODS

Twenty-two fingers (14 volunteers, 3 injured climbers) were scanned using a sagittal T1 turbo spin echo sequence (repetition time: 400 ms, echo time: 14 ms, slice thickness: 5 mm) in six consecutive finger positions from stretched to maximum possible flexion.

RESULTS

No pulley lesion was found in volunteers. Bowstringing was detected in 3 injured fingers including the A3 pulley.

CONCLUSION

Semi-dynamic MRI is an technique that is easy to perform to identify injuries of the A3 pulley ligament that were not seen on standard imaging.

Injuries to the Collateral Ligaments of the Metacarpophalangeal and Interphalangeal Joints: Sonographic Appearance

Injuries to the collateral ligaments of the metacarpophalangeal (MCP) and interphalangeal (IP) joints are commonly encountered in both athletes and nonathletes. They require prompt evaluation to ensure proper management and prevent loss of joint motion and permanent disability. Imaging is often required to confirm the diagnosis and assess injury severity. This review article aims to provide physicians with guidelines for sonographic assessment of the collateral ligaments of the MCP and IP and related injuries. Sonographic features of ligament injuries ranging from sprains and partial-thickness tears to full-thickness tears are described. Specific lesions of the ulnar collateral ligament of the thumb MCP joint, such as gamekeeper's thumb, skier's thumb, and Stener lesions, are also included. In conclusion, sonography is effective in evaluating the collateral ligaments of the MCP and IP joints and related injuries and represents a valuable tool for diagnosis.

Sports Injury-Related Fingers and Thumb Deformity Due to Tendon or Ligament Rupture

Background:

Hand injuries are very common in sports, such as skiing and ball sports. One of the major reasons causing hand and finger deformity is due to ligament and tendon injury. The aim of this study was to investigate if the high-resolution 3T magnetic resonance imaging (MRI) can demonstrate the complex anatomy of the fingers and thumb, especially the tendons and ligaments, and provide the accurate diagnosis of clinically important fingers and thumbs deformity due to ligamentous and tendinous injuries during sport activities.

Methods:

Sixteen fresh un-embalmed cadaveric hands were harvested from eight cadavers. A total of 20 healthy volunteers' hands and 44 patients with fingers or thumb deformity due to sports-related injuries were included in this study. All subjects had MR examination with T1-weighted images and proton density-weighted imaging with fat suppression (PD FS) in axial, coronal, and sagittal plane, respectively. Subsequently, all 16 cadaveric hands were sliced into 2-mm thick slab with a band saw (six in coronal plane, six in sagittal plane, and four in axial plane). The correlation of anatomic sections and the MRI characteristics of tendons of fingers and the ulnar collateral ligament (UCL) at the metacarpal phalangeal joint (MCPJ) of thumb between 20 healthy volunteers and 44 patients (confirmed by surgery) were analyzed.

Results:

The normal ligaments and tendons in 16 cadaveric hands and 20 volunteers' hands showed uniform low-signal intensity on all the sequences of the MRI. Among 44 patients with tendinous and ligamentous injuries in the fingers or thumb, 12 cases with UCL injury at MCPJ of the thumb (Stener lesion = 8 and non-Stener lesion = 4), 6 cases with the central slip injury, 12 cases with terminal tendon injury, and 14 cases with flexor digitorum profundus injury. The ligaments and tendons disruption manifested as increased signal intensity and poor definition, discontinuity, and heterogeneous signal intensity of the involved ligaments and tendons.

Conclusions:

Sports injury-related fingers and thumb deformity are relatively common. MRI is an accurate method for evaluation of the anatomy and pathologic conditions of the fingers and thumb. It is a useful tool for accurate diagnosis of the sports-related ligaments and tendons injuries in hand.

Label-free photoacoustic microscopy for in-vivo tendon imaging using a fiber-based pulse laser

Tendons are tough, flexible, and ubiquitous tissues that connect muscle to bone. Tendon injuries are a common musculoskeletal injury, which affect 7% of all patients and are involved in up to 50% of sports-related injuries in the United States. Various imaging modalities are used to evaluate tendons, and both magnetic resonance imaging and sonography are used clinically to evaluate tendons with non-invasive and non-ionizing radiation. However, these modalities cannot provide 3-dimensional (3D) structural images and are limited by angle dependency. In addition, anisotropy is an artifact that is unique to the musculoskeletal system. Thus, great care should be taken during tendon imaging. The present study evaluated a functional photoacoustic microscopy system for in-vivo tendon imaging without labeling. Tendons have a higher density of type 1 collagen in a cross-linked triple-helical formation (65–80% dry-weight collagen and 1–2% elastin in a proteoglycan-water matrix) than other tissues, which provides clear endogenous absorption contrast in the near-infrared spectrum. Therefore, photoacoustic imaging with a high sensitivity to absorption contrast is a powerful tool for label-free imaging of tendons. A pulsed near-infrared fiber-based laser with a centered wavelength of 780 nm was used for the imaging, and this system successfully provided a 3D image of mouse tendons with a wide field of view (5 × 5 mm²).

High-resolution 3-T MRI of the triangular fibrocartilage complex in the wrist: injury pattern and MR features

OBJECTIVES

To investigate if using high-resolution 3-T MRI can identify additional injuries of the triangular fibrocartilage complex (TFCC) beyond the Palmer classification.

MATERIALS AND METHODS

Eighty-six patients with surgically proven TFCC injury were included in this study. All patients underwent high-resolution 3-T MRI of the injured wrist. The MR imaging features of TFCC were analyzed according to the Palmer classification.

RESULTS

According to the Palmer classification, 69 patients could be classified as having Palmer injuries (52 had traumatic tears and 17 had degenerative tears). There were 17 patients whose injuries could not be classified according to the Palmer classification: 13 had volar or dorsal capsular TFC detachment and 4 had a horizontal tear of the articular disk.

CONCLUSION

Using high-resolution 3-T MRI, we have not only found all the TFCC injuries described in the Palmer classification, additional injury types were found in this study, including horizontal tear of the TFC and capsular TFC detachment. We propose the modified Palmer classification and add the injury types that were not included in the original Palmer classification.

Case 247: Jersey Finger of the Fifth Finger

History A 34-year-old man without underlying medical conditions came to the emergency department for evaluation of persistent pain over the volar portion of his right fifth finger after a fall during a football match 3 days before. At physical examination, the injured finger was swollen and purple. Passive and active flexion of the proximal and distal interphalangeal joints were compromised, without interphalangeal instability. Radiography was performed in the emergency department, and the patient was released with a diagnosis of a fifth digit sprain. After the senior radiologist (V.M.C.) reviewed the radiographs, the patient was called back for assessment with ultrasonography (US) on the same day. US was performed with an Aplio 500 unit (Toshiba Medical Systems, Tokyo, Japan) using a multifrequency linear array 7.2-18.0-MHz PLT-1204BX transducer focused at the level of the flexor tendon. The patient was sitting in front of the examiner, with the hand lying palm up on the examination bed. No abnormality was observed during color Doppler US.

Complex lesion of the third metacarpophalangeal joint: complete tear of the radial collateral and deep transverse metacarpal ligament

Injuries of collateral ligaments of MCPs joints are often underdiagnosed but have to be considered serious traumas of the hand. In many cases they concern thumb and rarely long fingers. Closed rupture of the deep transverse metacarpal ligament (DTML) is an unusual parallel injury. Both lesions present similar symptoms included local pain, swelling, ecchymosis and deviation of the finger in flexion and can be misdiagnosed. We describe the treatment of a 34 years old woman who sustained a complex lesion of the soft tissues of third metacarpophalangeal joint with complete close tear of the radial collateral and deep transverse metacarpal ligament following a fall during a walk thus leading to a multiplanar instability. Surgery consisted in mini anchor repair or the collateral ligament tear, direct resorbable suture of DTML and a double k-wire stabilization. Follow up at 11 months has shown excellent functional outcomes.

High-resolution 3T Magnetic Resonance Imaging of the Triangular Fibrocartilage Complex in Chinese Wrists: Correlation with Cross-sectional Anatomy

BACKGROUND

The injury of the triangular fibrocartilage complex (TFCC) is a common cause of ulnar-sided wrist pain. The aim of this study was to investigate if the high-resolution 3T magnetic resonance imaging (MRI) could demonstrate the detailed complex anatomy of TFCC in Chinese.

METHODS

Fourteen Chinese cadaveric wrists (from four men and three women; age range at death from 30 to 60 years; mean age at 46 years) and forty healthy Chinese wrists (from 20 healthy volunteers, male/female: 10/10; age range from 21 to 53 years with a mean age of 32 years) in Beijing Jishuitan Hospital from March 2014 to March 2016 were included in this study. All cadavers and volunteers had magnetic resonance (MR) examination of the wrist with coronal T1-weighted and proton density-weighted imaging with fat suppression in three planes, respectively. MR arthrography (MRAr) was performed on one of the cadaveric wrists. Subsequently, all 14 cadaveric wrists were sliced into 2 mm thick slab with band saw (six in coronal plane, four in sagittal plane, and four in axial plane). The MRI features of normal TFCC were analyzed in these specimens and forty healthy wrists.

RESULTS

Triangular fibrocartilage, the ulnar collateral ligament, and the meniscal homolog could be best observed on images in coronal plane. The palmar and dorsal radioulnar ligaments were best evaluated in transverse plane. The ulnotriquetral and ulnolunate ligaments were best visualized in sagittal plane. The latter two structures and the volar and dorsal capsules were better demonstrated on MRAr.

CONCLUSION

High-resolution 3T MRI is capable to show the detailed complex anatomy of the TFCC and can provide valuable information for the clinical diagnosis in Chinese.

In vivo MRI of the human finger at 7 T

Purpose

To demonstrate a dedicated setup for ultrahigh resolution MR imaging of the human finger in vivo.

Methods

A radiofrequency coil was designed for optimized signal homogeneity and sensitivity in the finger at ultrahigh magnetic field strength (7 T), providing high measurement sensitivity. Imaging sequences (2D turbo‐spin echo (TSE) and 3D magnetization‐prepared rapid acquisition gradient echo (MPRAGE)) were adapted for high spatial resolution and good contrast of different tissues in the finger, while keeping acquisition time below 10 minutes. Data was postprocessed to display finger structures in three dimensions.

Results

3D MPRAGE data with isotropic resolution of 200 µm, along with 2D TSE images with in‐plane resolutions of 58 × 78 µm² and 100 × 97 µm², allowed clear identification of various anatomical features such as bone and bone marrow, tendons and annular ligaments, cartilage, arteries and veins, nerves, and Pacinian corpuscles.

Conclusion

Using this dedicated finger coil at 7 T, together with adapted acquisition sequences, it is possible to depict the internal structures of the human finger in vivo within patient‐compatible measurement time. It may serve as a tool for diagnosis and treatment monitoring in pathologies ranging from inflammatory or erosive joint diseases to injuries of tendons and ligaments to nervous or vascular disorders in the finger. Magn Reson Med 79:588–592, 2018. © 2017 The Authors Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

Imaging of Sports-related Hand and Wrist Injuries: Sports Imaging Series

Hand and wrist injuries are common occurrences in amateur and professional sports and many of them are sport-specific. These can be divided into two categories: traumatic injuries and overuse injuries. The aim of this article is to review the most common hand and wrist sports-related lesions. Acute wrist injuries are predominantly bone fractures, such as those of the scaphoid, hamate hook, and ulnar styloid. Ligament lesions are more challenging for radiologists and may lead to carpal instability if undiagnosed. Overuse wrist injuries are mainly represented by tendinous disorders, with De Quervain syndrome and extensor carpi ulnaris tendon disorders being the most common among them; however, there are other possible disorders such as impaction syndromes, stress fractures, and neurovascular lesions. Finally, finger lesions, including closed-tendon injuries (mallet and boutonniere injuries, jersey finger, and boxer's knuckle), flexor pulley injuries, and skier's thumb, should also be detected. (©) RSNA, 2016 Online supplemental material is available for this article.

Sports-related wrist and hand injuries: a review

Background

Hand and wrist injuries are common during athletics and can have a significant impact especially if initially disregarded. Due to their high level of physical demand, athletes represent a unique subset of the population.

Main body

The following is an overview of hand and wrist injuries commonly seen in athletics. Information regarding evaluation, diagnosis, conservative measures, and surgical treatment are provided.

Conclusion

Knowledge of these entities and special consideration for the athlete can help the team physician effectively treat these players and help them achieve their goals.

Traumatic Extensor Tendon Injuries to the Hand: Clinical Anatomy, Biomechanics, and Surgical Procedure Review

The extensor apparatus is a complex muscle-tendon system that requires integrity or optimal reconstruction to preserve hand function. Anatomical knowledge and the understanding of physiopathology of extensor tendons are essential for an accurate diagnosis of extensor tendon injuries (ETIs) of the hand and wrist, because these lesions are complex and commonly observed in clinical practice. A careful clinical history and assessment still remain the first step for the diagnosis, followed by US and MR to confirm the suspect of ETI or to investigate some doubtful conditions and rule out associate lesions. During last decades the evolution of surgical techniques and rehabilitative treatment protocol led to gradual improvement in clinical results of ETI treatment and surgical repair. Injury classification into anatomical zones and the evaluation of the characteristics of the lesions are considered key points to select the appropriate treatment for ETI. Both conservative and surgical management can be indicated in ETI, depending on the anatomical zone and on the characteristics of the injuries. As a general rule, an attempt of conservative treatment should be performed when the lesion is expected to have favorable result with nonoperative procedure. Many surgical techniques have been proposed over the time and with favorable results if the tendon injury is not underestimated and adequately treated. Despite recent research findings, a lack of evidence-based knowledge is still observed in surgical treatment and postoperative management of ETI. Further clinical and biomechanical investigations would be advisable to clarify this complex issue.

Clinical evaluation vs magnetic resonance imaging of the skier's thumb: A prospective cohort of 30 patients

INTRODUCTION

A skiers thumb, or a partial or complete rupture of the ulnar collateral ligament (UCL) is a clinical diagnosis. Swelling, pain, natural left-right difference and inexperience of a young physician can cause difficulty to correctly diagnose this injury. However, our theory is that any physician, given the correct instructions, should be able to diagnose this injury solely on clinical findings, without the necessity of additional imaging.

MATERIAL AND METHODS

In a large Dutch teaching hospital, physicians (residents with working experience of 6months-3years) working at the ER received instructions for physical examination. Patients >18 years, with an injury <1 week old, suspected of a true skier's thumb had an MRI reported by two independent radiologists to confirm the diagnosis.

RESULTS

Thirty patients were included. Seven patients had no fixed endpoint (23%), all had a complete ligamentous rupture of the UCL on MRI, of which three patients had a Stener lesion. Fifteen patients (50%) met with the criteria  >35° laxity in extension of MCP/ >20° laxity in 30° flexion of the MCP. Of these, thirteen patients (81%) had a complete rupture (nine Stener lesions (56%)). One patient had a partial injury and one patient had no UCL-injury. Eight patients (27%) had inconclusive results during physical examination. Of these, two had a complete rupture (40%, 1 Stener). Three patients had a partial rupture and three patients had an intact UCL.

CONCLUSION

A skier's thumb can be diagnosed by any resident when correctly instructed. Additional imaging when diagnosing a skier's thumb should be reserved in cases when physical examination remains inconclusive.

Emergency Magnetic Resonance Imaging of Musculoskeletal Trauma

Musculoskeletal (MSK) trauma is commonly encountered in the emergency department. Computed tomography and radiography are the main forms of imaging assessment, but the use of magnetic resonance (MR) imaging has become more common in the emergency room (ER) setting for evaluation of low-velocity/sports-related injury and high-velocity injury. The superior soft tissue contrast and detail provided by MR imaging gives clinicians a powerful tool in the management of acute MSK injury in the ER. This article provides an overview of techniques and considerations when using MR imaging in the evaluation of some of the common injuries seen in the ER setting.

Change in the collateral and accessory collateral ligament lengths of the proximal interphalangeal joint using cadaveric model three-dimensional laser scanning

The purpose of this study was to assess the lengths of the index and middle finger proximal interphalangeal joint ligaments and determine the relative changes in the collateral and accessory collateral ligament lengths at 0°, 45° and 90° flexion. We generated three-dimensional scans of 16 finger (eight index and eight middle) proximal interphalangeal joints to assess relative changes in ligament length. Significant changes were found between 45°-90° and 0°-90° for the ulnar collateral ligament of the index finger and both collateral ligaments of the middle finger between 45°-90° and 0°-90°. No significant changes in length were found for the radial collateral ligament of the index finger or the accessory collateral ligaments of the index and middle fingers. Overall, it was found that the collateral ligament length changed significantly, but there was no significant change in the accessory collateral ligaments.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Review of Acute Traumatic Closed Mallet Finger Injuries in Adults

In adults, mallet finger is a traumatic zone I lesion of the extensor tendon with either tendon rupture or bony avulsion at the base of the distal phalanx. High-energy mechanisms of injury generally occur in young men, whereas lower energy mechanisms are observed in elderly women. The mechanism of injury is an axial load applied to a straight digit tip, which is then followed by passive extreme distal interphalangeal joint (DIPJ) hyperextension or hyperflexion. Mallet finger is diagnosed clinically, but an X-ray should always be performed. Tubiana's classification takes into account the size of the bony articular fragment and DIPJ subluxation. We propose to stage subluxated fractures as stage III if the subluxation is reducible with a splint and as stage IV if not. Left untreated, mallet finger becomes chronic and leads to a swan-neck deformity and DIPJ osteoarthritis. The goal of treatment is to restore active DIPJ extension. The results of a six- to eight-week conservative course of treatment with a DIPJ splint in slight hyperextension for tendon lesions or straight for bony avulsions depends on patient compliance. Surgical treatments vary in terms of the approach, the reduction technique, and the means of fixation. The risks involved are stiffness, septic arthritis, and osteoarthritis. Given the lack of consensus regarding indications for treatment, we propose to treat all cases of mallet finger with a dorsal glued splint except for stage IV mallet finger, which we treat with extra-articular pinning.

Current status of ultrasonography of the finger

The recent development of advanced high-resolution transducers has enabled the fast, easy, and dynamic ultrasonographic evaluation of small, superficial structures such as the finger. In order to best exploit these advances, it is important to understand the normal anatomy and the basic pathologies of the finger, as exemplified by the following conditions involving the dorsal, volar, and lateral sections of the finger: sagittal band injuries, mallet finger, and Boutonnière deformity (dorsal aspect); flexor tendon tears, trigger finger, and volar plate injuries (volar aspect); gamekeeper's thumb (Stener lesions) and other collateral ligament tears (lateral aspect); and other lesions. This review provides a basis for understanding the ultrasonography of the finger and will therefore be useful for radiologists.

Delineation of extensor tendon of the hand by MRI: usefulness of "soap-bubble" mip processing technique

To evaluate the capability of the "Soap-Bubble" maximum intensity projection (MIP) processing technique in visualisation of extensor tendons of the hand, 36 intact subjects and seven patients with surgically confirmed extensor tendon rupture were examined. Three-dimensional T1-weighted turbo spin echo (3DT1TFE) MRI was performed using a sensitivity encoding flex coil, followed by Soap-Bubble MIP processing. For patients with extensor tendon ruptures, MRI findings and intraoperative findings were compared. As results, with only 3DT1TFE sequence, the entire extensor tendons that run along the arch of the hand were not shown on one image, but were visualised with addition of Soap-Bubble MIP. Although delineation of the extensor pollicis longus was poor in 27/43 subjects, it was much improved by the combination of water-suppression technique. MRI findings and intraoperative findings agreed in all patients. Soap-Bubble MIP processing with addition of water-suppression technique is considered useful for visualising the extensor tendons of the hand.

MRI of the hand and fingers

Injuries of the hand and fingers occur commonly in professional athletes as well as weekend warriors. Magnetic resonance imaging plays a vital role in the evaluation of these injuries for accurate diagnosis, preoperative planning, potential complication, and follow-up during rehabilitation. A detailed analysis of these smaller structures necessitates optimal imaging quality coupled with comprehensive knowledge of the imaging anatomy. In this article, we discuss technical aspects and normal anatomy of hand and fingers imaging on magnetic resonance imaging. This section is followed by discussion of soft tissue and osseous injuries including mechanism of injury, clinical presentation, and imaging findings.

Fracture of the sesamoid bones of the thumb associated with volar plate injury: ultrasound diagnosis

The fractures of sesamoid bones of the hand are rare, sometimes the diagnosis is missed. We report a case of fracture of both the ulnar and radial sesamoids of the metacarpophalangeal (MCP) joint of the thumb. The trauma (hyperextension of the thumb during a soccer match) also caused a lesion of the volar plate. The diagnosis was made by ultrasound (US) and confirmed by CT scan.