The role of imaging in diagnosing diseases of the distal radioulnar joint, triangular fibrocartilage complex, and distal ulna

Rehabilitation Strategies for Wrist Pain in a Patient With Thalassemia Major and Distal Ulnar Hypoplasia: A Case Report

This case study examines the rehabilitation process of a 24-year-old female patient with thalassemia major (TM), a hereditary hemoglobinopathy, who also suffered from distal ulnar hypoplasia, a congenital anomaly that causes pain and affects the wrist joint's strength and range of motion. The patient underwent a comprehensive physical rehabilitation program that aimed to address the challenges posed by ulnar hypoplasia. This program included a combination of customized exercises, splinting, and orthotic interventions to improve hand and wrist function. By adopting a multidisciplinary approach, the patient experienced significant improvements in mobility, strength, and overall quality of life. This case highlights the significance of personalized rehabilitation strategies in managing complex medical conditions, demonstrating the potential for positive outcomes even in patients with dual diagnoses of TM and ulnar hypoplasia.

Relationship of ulna styloid fracture to the distal radio-ulnar joint stability. A clinical, functional, and radiographic outcome study

BACKGROUND

Ulna styloid fracture occurs approximately about 55% of all distal end of radius fractures. However, the clinical and functional outcome of these fractures remains indefinite.

RESULTS

Only 56 patients with distal radius fractures had concomitant ulna styloid fractures. The mean age was 32 years (range: 18-69; SD: ± 12.7). The majority were men. The mean time from injury was 18.7 months (range: 6-84; SD: ± 13.3). The most common was Frykman 2, followed by 6, type 8, and type 4. All were closed fractures; 60.7% were base, and 39.3% were tip fractures. 50% were treated with casting, 48.3% plating, and 1.8% external fixation. The mean period of casting was 7.67 weeks (range: 4-16; SD ± 3.1). The ulna styloid was united in 35.7%. There is no significant difference in the range of movement between those with ulna styloid union and non-union. The Ballottement test and Piano key sign was statistically insignificant between both groups. All the displacements were dorsal except in 1 case. The mean displacement of ulna styloid is 1.88mm (SD±1.08, Range: 0.20-4.60mm). The mean VAS score at rest and work is not statistically significant. The mean grip strength and functional score (DASH) are similar in both groups.

CONCLUSION

Ulna styloid fractures do not contribute to the DRUJ instability and the status of the union of the ulna styloid and the site of the ulna styloid fracture (tip or base) did not have a bearing on the range of movement and functional status of the affected wrist. Temporary DRUJ immobilization might allow TFCC recovery.

A new quantitative evaluation system for distal radioulnar joint instability using a three-dimensional electromagnetic sensor

BACKGROUND

The accurate assessment of distal radioulnar joint (DRUJ) instability is still challenging as there is no established objective evaluation method. This study aimed to develop a noninvasive measurement method using a three-dimensional electromagnetic sensor system (EMS) to quantitatively assess and characterize the normal DRUJ movement in healthy volunteers.

METHODS

The DRUJ movement was mimicked using both a block model and saw bone. Movement of the models was measured by EMS, and the accuracy and reproducibility of the measurements were assessed. In vivo measurement was performed in a sitting position with the elbow flexed and the forearm pronated. One sensor each was attached to the distal radial shaft and the ulnar head. The examiners fixed the distal radius and the carpal bones, moved the ulnar head from the dorsal to the volar side and measured the dorsovolar translation. The volar translation was measured by EMS and ultrasonography, and the correlation coefficient was calculated. The dorsovolar translation was evaluated in 14 healthy volunteers (7 men and 7 women) by three hand surgeons. The intraclass and inter-rater correlation coefficients (ICCs), the differences between the dominant and non-dominant sides and between men and women were assessed.

RESULTS

The accuracy and reproducibility assessment results of the EMS showed high accuracy and reproducibility. In the comparison between EMS and ultrasonography, the correlation coefficient was 0.920 (p = 0.16 × 10^-3). The ICC (1,5) for the intra-rater reliability was 0.856, and the ICC (2,5) for inter-rater reliability was 0.868. The mean ulnar head translation and difference between dominant and non-dominant sides were 6.00 ± 1.16 mm (mean ± SD) and - 0.12 ± 0.40 mm, respectively. There were no significant differences between any of the parameters.

CONCLUSIONS

A new measurement method using EMS could evaluate DRUJ movement with high accuracy, reproducibility, and intra- and inter-rater reliability. In healthy volunteers, the dorsovolar ulnar head translation was 6.00 mm. The difference between the dominant and non-dominant sides was < 1.0 mm with no significant difference. EMS provided an objective, non-invasive, real-time assessment of dynamic changes in the DRUJ. These findings could be useful in the treatment of patients with DRUJ instability.

Comparison of visibility of ulnar sided triangular fibrocartilage complex (TFCC) ligaments between isotropic three-dimensional and two-dimensional high-resolution FSE MR images

OBJECTIVES

Assessment of the ulnar attachment of the triangular fibrocartilage complex (TFCC) in a neutral forearm position remains challenging. Our study aims to evaluate the visibility of ulnar sided TFCC on 3 T MRI and compare isotropic 3D FSE sequences utilizing multiplanar reformation (MPR) with standard high-resolution 2D FSE sequences.

METHODS

Ninety-nine MRI wrist studies in patients with wrist pain were retrospectively analyzed. Patients were scanned with a neutral forearm position and reviewed with isotropic 3D coronal FSE proton density-weighted images (PDWI) and 2D coronal FSE PDWI. MPR was used for 3D assessment. Visibility of the dorsal radioulnar ligament (DRUL), triangular ligament (TL), and volar radioulnar ligament (VRUL) was assessed by three raters utilizing a five-point grading scale. Grades were compared between 2D and 3D sequences. Intrarater and interrater reliability for the delineation of anatomic structures was measured by Spearman's rank correlation coefficient, Cohen's kappa, and percentage of exact agreement/agreement within a range of ±1 score point.

RESULTS

Visibility grades in 3D were statistically significantly higher than those in 2D in all ligaments by all raters (p < 0.01). In Spearman's rank correlation coefficient and Cohen's kappa analysis, interrater correlations and agreements are variable but tended to be higher on 3D than on 2D. Both 2D and 3D sequences showed high intrarater exact agreement in all ligaments (80-91 % on 2D and 88-95 % on 3D). All exact interrater agreements on 3D were acceptable for TL (83-93 %) and acceptable to close to acceptable for VRUL (72-96 %).

CONCLUSION

The utilization of isotopic 3D imaging combined with MPR function significantly improves visibility of ulnar attachment of the TFCC.

Chronic Distal Radioulnar Joint Instability

The distal radioulnar joint is inherently unstable, relying primarily on ligaments for stability. Disruption of the joint-stabilizing structures can occur in isolation or concomitantly with osseous trauma. Instability can result from dislocations, fractures, ligament injuries, or malunions. Untreated instability alters wrist and forearm kinematics, leading to pain, weakness, and possibly arthritis. In chronic instability, the native ligaments may not be reparable, necessitating a reconstructive procedure.

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.

The Acutely Injured Wrist

Wrist traumas are a frequent clinical emergency for which instrumental imaging assessment is required. The purpose of this article is to review the role of imaging assessment of traumatic wrist injuries, with particular reference to fractures and associated lesions.

Current perspectives in conventional and advanced imaging of the distal radioulnar joint dysfunction: review for the musculoskeletal radiologist

Distal radioulnar joint (DRUJ) dysfunction is a common cause of ulnar sided wrist pain. Physical examination yields only subtle clues towards the underlying etiology. Thus, imaging is commonly obtained towards an improved characterization of DRUJ pathology, especially multimodality imaging, which is frequently resorted to arrive at an accurate diagnosis. With increasing use of advanced MRI and CT techniques, DRUJ imaging has become an important part of a musculoskeletal radiologist's practice. This article discusses the normal anatomy and biomechanics of the DRUJ, illustrates common clinical abnormalities, and provides a comprehensive overview of the imaging evaluation with an insight into the role of advanced cross-sectional modalities in this domain.

Kinematic Analysis of the Distal Radioulnar Joint in Asymptomatic Wrists Using 4-Dimensional Computed Tomography-Motion Pattern and Interreader Reliability

PURPOSE

The aim of this study was to determine the normal measurement values and interobserver performance of the distal radioulnar joint during wrist pronation-supination using 4-dimensional computed tomography (CT).

METHODS

Four-dimensional CT examinations were performed on the asymptomatic contralateral wrists of 10 patients with unilateral chronic wrist pain. Measurements were conducted using the modified radioulnar (mRU) line and epicenter (Epi) methods. Volar subluxation of the ulnar head was demonstrated with negative values. Wilcoxon rank sum test was used to determine the measurement changes. Interobserver agreements were assessed using interclass correlation coefficients.

RESULTS

In pronation, mRU line measurements (median, 0.09; interquartile range, 0-0.15) were significantly larger than in supination (median, -0.1; interquartile range, -0.18 to 0; P = 0.008).The Epi measurements were not significantly different in pronation (median, 0.03; interquartile range, 0.01-0.07) and supination (median, 0.06; interquartile range, 0.01-0.1; P = 0.799). There was an excellent inter-observer agreement between the two readers using mRU and Epi methods in pronation (0.982, 0.898), midpoint (0.994, 0.827) and supination (0.989, 0.972) positions, respectively.

CONCLUSIONS

Using 4-dimensional CT examination, distal radioulnar joint kinematics in asymptomatic wrists demonstrate excellent interobserver agreements with increased volar ulnar subluxation with supination as detected using mRU, but not the Epi method.

Anatomy and injuries of the pediatric wrist: beyond the basics

Ligamentous injuries of the pediatric wrist, once thought to be relatively uncommon, are increasingly recognized in the context of acute high-energy mechanism trauma and chronic axial loading, including those encountered in both recreational and high-performance competitive sports. Recent advances in MR-based techniques for imaging the pediatric wrist allow for sensitive identification of these often radiographically occult injuries. Detailed knowledge of the intrinsic and supportive extrinsic ligamentous complexes, as well as normal developmental anatomy and congenital variation, are essential to accurately diagnose injuries to these structures. Early identification of ligamentous injury of the pediatric wrist is essential within the conservative treatment culture of modern pediatric orthopedics because treatment of these lesions often necessitates surgery, and outcomes often depend on early and sometimes aggressive intervention. In this article, we review MR arthrogram technique and pediatric wrist anatomy, and correlate appearances on MR and selected ligamentous pathologies of the pediatric wrist.

Diagnostic modalities for distal radioulnar joint

The first imaging modality in patients suspected of distal radioulnar joint pathology should be conventional radiography to exclude or diagnose wrist pathology including osteoarthritis, rheumatoid arthritis, calcium pyrophosphate deposition disease, (healed) fractures, or impaction syndromes. When conventional radiography is inconclusive, high resolution 3 Tesla magnetic resonance imaging is advised. We provide a broad overview of the literature regarding the use of intra-articular contrast both with computed tomography (CTA) or magnetic resonance imaging (MRA). Conventional arthrography and unenhanced computed tomography are not indicated. This article discusses the most useful imaging techniques in terms of clinical indications, patient positioning, technical imaging requirements, and diagnostic performance in patients with suspected distal radioulnar joint pathology. Furthermore, the most prevalent pathologies are discussed, with the focus on imaging characteristics in both stable and unstable distal radioulnar joints.

Magnetic Resonance Arthrography of the Wrist and Elbow

Magnetic resonance (MR) arthrography of the wrist and elbow is useful for detecting a variety of intra-articular pathologies. MR dictations should address whether intrinsic ligament tears of the wrist are partial-thickness or full-thickness, and involve the dorsal, membranous, and/or volar components of the ligaments. With regard to elbow soft tissue pathology, partial-thickness tears of the anterior band of the ulnar collateral ligament in overhead-throwing athletes are well evaluated with MR arthrography. MR arthrography also is helpful in staging osteochondritis dissecans of the capitellum, caused by repetitive valgus impaction injury in adolescent or young adult baseball pitchers.

Distal Radioulnar Joint Instability

Distal radioulnar joint (DRUJ) instability is a common clinical condition but a frequently missed diagnosis. Both surgical and nonsurgical treatments are possible for chronic cases of DRUJ instability. Nonsurgical treatment can be considered as the primary therapy in less active patients, while surgery should be considered to recover bone and ligament injuries if nonsurgical treatment fails to restore forearm stability and function. The appropriate choice of treatment depends on the individual patient and specific derangement of the DRUJ.

What's in a name? Upper extremity fracture eponyms (Part 1)

Eponymous extremity fractures are commonly encountered in the emergency setting. Correct eponym usage allows rapid, succinct communication of complex injuries. We will review both common and less frequently encountered extremity fracture eponyms, focusing on imaging features to identify and differentiate these injuries. We focus on plain radiographic findings, with supporting computed tomography (CT) images. For each injury, important radiologic descriptors are discussed which may need to be communicated to consultants. Aspects of management and follow-up imaging recommendations are included. This is a two-part review: Part 1 focuses on fracture eponyms of the upper extremity, while Part 2 covers fracture eponyms of the lower extremity.