MR imaging findings in ulnar-sided wrist impaction syndromes

Is ulnar shortening osteotomy effective for the treatment of ulnar styloid impaction syndrome compared to ulnar impaction syndrome?

PURPOSE

This study aimed at evaluating the outcomes of ulnar shortening osteotomy (USO) for the treatment of ulnar styloid impaction syndrome (USIS) and to compare them with those of USO for the treatment of ulnar impaction syndrome (UIS).

METHODS

We enrolled 144 patients who underwent USO between March 2015 and October 2021. The patients were divided into a UIS group (group I, n = 93) and a USIS group (group II, n = 51). Clinical and radiological parameters, including Disabilities of the Arm, Shoulder, and Hand (DASH) score, ulnar variance, ulnar styloid length, and ulnar styloid process index (USPI), were collected pre-operatively and one year post-operatively, and a comparative analysis was performed.

RESULTS

The DASH score showed significant improvement in both groups (p < .001 and p < .001), and there was no significant difference between the two groups one year after surgery (p = .143). The USPI was significantly different between the two groups (p < .001). The ulno-lunate and ulno-triquetrum distances showed significant increases in both groups, with significant differences between the two groups (p = .020, and p < .001, respectively). The incidence of post-operative arthritic changes in the distal radioulnar joint was significantly greater in the UIS group than that in the USIS group (21 vs 3, respectively; p = .017). No remarkable differences were observed in the post-operative evidence of chondromalacia at the last follow-up between the two groups.

CONCLUSION

The USO, which was performed as a treatment for USIS showed reliable outcomes compared to the USO for the treatment of UIS. Therefore, USO is a viable option for the treatment of USIS.

Abnormal MRI signal intensity of the triangular fibrocartilage complex in asymptomatic wrists

We investigated abnormal MRI findings of the triangular fibrocartilage complex in 154 asymptomatic volunteers (21-79 years). Except prevalence, we focused on the morphological features of abnormal signals in relation to age. The majority of full-thickness tears were located in the articular disc (63 participants). The incidence of disc perforation with characteristics of ulnar impaction syndrome increased significantly with age. Asymptomatic full-thickness tears of the ulnar attachment were found in ten participants (seven over 60 years old). The proximal and distal laminae of the ulnar attachment could not be differentiated in 36 participants. In conclusion, MRI is of limited value for the elderly in diagnosing triangular fibrocartilage disorders. For young subjects, MRI is still valuable, especially in diagnosing ulnar detachment, although the ability to distinguish between proximal and distal laminae remains questionable. Disc perforations in volunteers mimicked ulnar impaction syndrome, therefore age, clinical signs and other factors should also be considered in clinical diagnosis.Level of evidence: III.

Ulnar variance in distal radial fractures: assessment and interpretation

We explored patterns of shortening of the distal radius and investigated the effect of displacement on 'ulnar variance' in 250 patients with distal radial fractures. A small number of patients (5%) had a fracture that resulted in true shortening. Thirty-two per cent had fractures that appeared short, but lateral radiographs revealed that the articular surface was tilted, with either the anterior or dorsal rim of the articular surface being proximal to the distal ulna but the other rim was distal to it. We recommend initial assessment of variance on lateral radiographs. If the anterior and dorsal rims of the distal radial articular surface are proximal to the distal ulna, then true shortening is present and lengthening and stabilization, to hold the radius distracted, should be considered. If only one rim is proximal to the distal ulna, then correction of the tilt will lessen the apparent positive variance.Level of evidence: IV.

How to Report: Wrist MRI

Knowledge of the imaging anatomy of the wrist is essential for reporting magnetic resonance imaging (MRI). This familiarity should include the carpal bones, tendons (extensor and flexor compartments), triangular fibrocartilage complex (TFCC), intrinsic and extrinsic ligaments, and nerves, especially the median and ulnar nerves. Limitations of MRI in visualizing these structures, particularly the intrinsic ligaments and the TFCC, need to be considered. This article outlines the main features to comment on when reporting common conditions of the wrist on MRI, with some examples of terminology that can be used to describe these abnormalities.

[What does the hand surgeon expect from the radiologist in diagnostic imaging of the hand?]

BACKGROUND

For hand surgeons, in addition to anamnesis and clinical examination, imaging is the essential component in diagnostics and the basis for therapy planning. The focus on the special field of the "hand" and the adjacent joints is limited with regard to the anatomical extent, but with regard to the possible clinical pictures it encompasses the entire range of pathological changes.

CLINICAL ISSUE

Which imaging techniques support the goal of maintaining the functionality of the hand?

PERFORMANCE

The carpal bones can be represented by computer tomography without superimposition. The navicular (scaphoid) should be evaluated sagittally in its longitudinal axis. MRI imaging is useful, for example, when assessing possible ligament injuries or ulnar-carpal complaints on the triangular disc. Stress images prove additional information in the case of of dynamic ligament or joint instabilities.

ACHIEVEMENTS

Imaging with conventional X‑rays is the basis of radiological diagnostics of the hand. In addition, the small structures of the hand and fingers to be assessed must be specifically visualized.

PRACTICAL RECOMMENDATION

In order to enable precise assessment of the fine and complex structures on the hand in relation to the clinical complaints, close communication of the anamnesis and questions with the radiologist is desirable.

[The ulnocarpal complex : New clinical and radiological considerations]

CLINICAL ISSUE

The triangular fibrocartilage complex (TFCC) is an anatomically complex structure with high demands on spatial and contrast resolution in imaging.

RADIOLOGICAL METHODS

The central, predominantly avascular articular disc can be distinguished from the ligamentous, vascularized periphery. Imaging methods include magnetic resonance imaging (MRI, preferably contrast-enhanced) as well as MR and computed tomography (CT) arthrography.

DIAGNOSTIC INNOVATIONS

While high-resolution MRI represents the standard diagnostic tool for the TFCC in general, arthrographic imaging is particularly useful for assessment of the foveal (proximal) lamina of the TFCC. In radiological reporting, the convergence of the TFCC periphery towards the ulnar styloid process and the ulnar fovea must be considered.

ACHIEVEMENTS

The Palmer classification is suitable for evaluating lesions of the articular disc, whereas the Atzei classification is superior for lesions of the ulnar TFCC insertions.

PRACTICAL RECOMMENDATION

Use of a high-resolution examination technique and anatomy-based image interpretation are important for reliable MRI of the TFCC.

Physeal bridges: causes, diagnosis, characterization and post-treatment imaging

The cartilaginous primary physis, or growth plate, at the end of long bones in children allows for longitudinal bone growth. A variety of insults to the physis can lead to physeal bridge formation, which in turn can lead to limb-shortening and angular deformities. This paper begins with a description of the causes, risk factors and mechanisms by which bridges form. Then it reviews the use of imaging in the diagnosis and characterization of bridges and in the evaluation of treatment and post-treatment complications. It is important for radiologists taking care of children to be aware of the indirect and direct imaging findings of physeal bridges to aid in their diagnosis, to be able to characterize bridges as part of preoperative planning, and to know the imaging finding of post-resection complications.

[Radiology of the distal radioulnar joint and the ulnocarpal complex]

X-ray images exposed in neutral position and radiocarpally centred are essential in imaging of the distal radioulnar joint (DRUJ). The anatomic orientation of the DRUJ is favourable for acquiring transaxial scans to display its anatomy, subtle derangements, osteoarthritis and intra-articular fractures free from superpositions. The triangular fibrocartilage complex (TFCC) is the most important stabilizer of the DRUJ. Provided that a focused clinical indication is given, high-resolution images are acquired, and an intra-venous or intra-articular contrast-agent is applied, all TFCC structures and destabilizing lesions can be displayed with the use of CT and MRI.

Correlation of the Lateral Wrist Radiograph to Ulnar Variance: A Cadaveric Study

PURPOSE

Both positive and negative ulnar variance have been implicated in a variety of wrist disorders. Surgery aims to correct the variance in these pathologic conditions. This necessitates accurate and reproducible measuring tools; however, the most accurate radiographic measurement technique remains unclear. The purposes of this study were to evaluate 3 methods for determining ulnar variance and to compare each with direct anatomic measurement in a cadaver model.

METHODS

We fixed 10 fresh above-elbow cadaver specimens in neutral rotation and obtained standardized fluoroscopic posteroanterior and lateral wrist images. A dorsal approach was performed and two independent investigators directly measured ulnar variance using digital calipers with the cartilage both intact and denuded. Ulnar variance was measured radiographically using the lateral, perpendicular, and central reference point methods. The reliability of each set of measurements (within a 1-mm cutoff) was assessed by the intraclass coefficient; agreement between radiographic and direct measurements was evaluated by the Bland-Altman method.

RESULTS

Each method of determining ulnar variance demonstrated near perfect agreement by the intraclass coefficient. The lateral radiograph method correlated highly with the directly measured ulnar variance with the cartilage denuded with an average measurement difference of 0.06 mm. No radiographic measurement technique demonstrated consistent agreement within 1 mm of the measured ulnar variance with the cartilage intact.

CONCLUSIONS

Ulnar variance measured by the lateral wrist radiograph technique correlates highly with the directly measured osseous ulnar variance. The remaining measurement techniques did not correlate reliably to within 1 mm of the directly measured ulnar variance with 95% confidence. No method was able to account accurately for the articular cartilage thicknesses at the lunate facet of the radius or the distal ulnar head, which we found to vary in an unpredictable manner. Whereas the lateral radiograph has been shown to allow for more reliable standardization of wrist position compared with the posteroanterior view, this study also highlights the inherent limitations of using static radiographic images in evaluating ulnar variance.

CLINICAL RELEVANCE

The results of the current study demonstrate the utility of the lateral wrist radiograph for assessing bony ulnar variance.

Prevalence and clinical characteristics of radiographic central triangular fibrocartilage complex tears in symptomatic and asymptomatic individuals younger than 50 years

BACKGROUND

Few studies have addressed the prevalence of central triangular fibrocartilage complex (TFCC) tears or their risk factors for symptom development. The aim of this study was to determine the prevalence of radiographic central TFCC tears in both symptomatic and asymptomatic individuals, and evaluate clinical characteristics of symptomatic individuals.

METHODS

In this retrospective case control study, 221 patients younger than 50 years who exhibited positive ulnocarpal provocation test and underwent MRI to identify abnormalities associated with TFCC were age- and sex-matched with 221 controls who had undergone hand or wrist MRI for tumorous lesions or pain in hand other than ulnar-sided wrist. Demographic and radiologic parameters including the degree of ulnar plus variance, the type of central TFCC lesions, the presence of ulna head or carpal bone enhancement, and cartilage degeneration of ulno-carpal or distal radio-ulnar joint were compared. Multivariable regression analysis was carried out to identify independent risk factors for symptom development in patients with central TFCC lesions.

RESULTS

The prevalence of central TFCC lesions was 68/221 in symptomatic patients, which was not significantly different from that (51/221) in asymptomatic controls. Patients in the symptomatic group had significantly greater ulnar plus variance (1.6 vs. 0.7). They were more likely to have type 1A tears and bony enhancement in ulnar head or carpus on MR images. Multivariable logistic regression analysis revealed that youth, female gender, and presence of bony enhancement were significant risk factors for symptom development in central TFCC lesions.

CONCLUSION

Based on the findings of this study, prevalence of central TFCC lesions detected on MRI in symptomatic patients seems to be similar to that in asymptomatic individuals. Younger age, female gender, and presence of bony enhancement on MR images seem to be risk factors for symptoms of central TFCC lesions.

Prognostic value of clinical and radiological findings for conservative treatment of idiopathic ulnar impaction syndrome

Ulnar impaction syndrome (UIS) is a common source of ulnar-sided wrist pain, yet not all cases of radiographic ulnar impaction are symptomatic. We retrospectively analyze clinical or radiologic factors that affect prognoses of conservative treatment for idiopathic UIS. A total of 114 patients who had been diagnosed with UIS were treated with 6 weeks of short arm orthosis followed by formal physiotherapy for 6 weeks, with lifestyle modification to limit aggravating movements. The response to treatment, including pain numeric rating scale on an ulnar provocation test, grip strength, Disability of the Arm, Shoulder, and Hand score (DASH), was assessed at 24-week follow-up. For the 24-week follow-up, 29 patients (25%) underwent ulnar shortening osteotomy due to persistent symptoms after conservative treatment, and 18 (16%) patients had pain scores of greater than 5, but they had not undergone surgery. After controlling for confounding variables, female gender (odds ratio (OR) 1.39), duration of symptom (OR 1.27), high pain NRS score on provocation test (OR 1.45), and enhanced carpal or distal ulna bone on MRI (OR 1.82) were associated with a higher likelihood of treatment failure. Knowledge of the factors offers physicians insight into predicting prognoses and helps patients set realistic expectations.

Arthroscopic Management of Ulnocarpal Impaction Syndrome and Ulnar Styloid Impaction Syndrome

Both ulnocarpal impaction syndrome and ulnar styloid impaction syndrome can produce ulnar wrist pain. The definition and clinical differentiation are explained. The relevant anatomy, biomechanics, causes, diagnosis, and arthroscopic treatments, as well as the surgical indications, techniques, and outcomes of these syndromes are discussed in detail.

Interobserver Agreement in Diagnosing Early-Stage Kienböck Disease on Radiographs and Magnetic Resonance Imaging

BACKGROUND

The appearance of early Kienböck disease on radiographs and magnetic resonance imaging (MRI) may be difficult to distinguish from other conditions that affect the lunate. We aimed to assess the interobserver agreement in the diagnosis of early Kienböck disease when evaluated on different imaging modalities.

METHODS

Forty-three hand surgeon members of the Science of Variation Group were randomized to evaluate radiographs and 35 hand surgeons to evaluate radiographs and MRI scans of 26 patients for the presence of Kienböck disease, the lunate type, and the ulnar variance. We used Fleiss' kappa analysis to assess the interobserver agreement for categorical variables and compared the κ values between the 2 groups.

RESULTS

We found that agreement on the diagnosis of early Kienböck disease was fair (κ, 0.36) among observers who evaluated radiographs alone and moderate (κ, 0.58) among observers who evaluated MRI scans in addition to radiographs, and that the difference in κ values was not statistically significant ( P = .057). Agreement did not differ between observers based on imaging modality with regard to the assessment of the lunate type ( P = .75) and ulnar variance ( P = .15).

CONCLUSIONS

We found, with the numbers evaluated, a notable but nonsignificant difference in agreement in favor of observers who evaluated MRI scans in addition to radiographs compared with radiographs alone. Surgeons should be aware that the diagnosis of Kienböck disease in the precollapse stages is not well defined, as evidenced by the substantial interobserver variability.

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.

The aging athlete: part 2, "boomeritis" of the upper extremity

OBJECTIVE

The purpose of this review is to describe the upper extremity injuries that frequently accompany aging, the typical clinical presentations, and the differential diagnoses with an emphasis on the injury most likely encountered with each presentation.

CONCLUSION

Expectation of continued participation in exercise and sports activities by the baby boomer population has presented new challenges to the medical field. The concepts behind factors that predispose older athletes to certain pathologic conditions that affect the muscles, tendons, and bones of the upper extremity must be understood.

Ulnar-sided wrist pain: evaluation and treatment of triangular fibrocartilage complex tears, ulnocarpal impaction syndrome, and lunotriquetral ligament tears

Ulnar-sided wrist pain is a common cause of upper extremity disability. Presentation can vary from acute traumatic injuries to chronic degenerative conditions. Because of its overlapping anatomy, complex differential diagnosis, and varied treatment outcomes, the ulnar side of the wrist has been referred to as the "black box" of the wrist, and its pathology has been compared with low back pain. Common causes of ulnar-sided wrist pain include triangular fibrocartilaginous complex injuries, lunotriquetrial ligament injuries, and ulnar impaction syndrome.

Ulnar-sided wrist pain. II. Clinical imaging and treatment

Pain at the ulnar aspect of the wrist is a diagnostic challenge for hand surgeons and radiologists due to the small and complex anatomical structures involved. In this article, imaging modalities including radiography, arthrography, ultrasound (US), computed tomography (CT), CT arthrography, magnetic resonance (MR) imaging, and MR arthrography are compared with regard to differential diagnosis. Clinical imaging findings are reviewed for a more comprehensive understanding of this disorder. Treatments for the common diseases that cause the ulnar-sided wrist pain including extensor carpi ulnaris (ECU) tendonitis, flexor carpi ulnaris (FCU) tendonitis, pisotriquetral arthritis, triangular fibrocartilage complex (TFCC) lesions, ulnar impaction, lunotriquetral (LT) instability, and distal radioulnar joint (DRUJ) instability are reviewed.

Reconstruction of the distal ulna: instability, impaction, impingement, and arthrosis

A number of afflictions may affect the distal radioulnar joint that can lead to severe pain, disuse, dysfunction, and disability. The disorders that affect this small anatomic region are complex, have multifactorial etiologies, and can sometimes present difficult diagnostic and treatment options. This article presents an overview of recent developments in the diagnosis and treatment of a variety of conditions that affect the joint and surrounding bone and soft tissues.

Ulnar-sided wrist pain: evaluation and treatment of triangular fibrocartilage complex tears, ulnocarpal impaction syndrome, and lunotriquetral ligament tears

Ulnar-sided wrist pain is a common cause of upper-extremity disability. Presentation can vary from acute traumatic injuries to chronic degenerative conditions. Because of its overlapping anatomy, complex differential diagnosis, and varied treatment outcomes, the ulnar side of the wrist has been referred to as the "black box" of the wrist, and its pathology has been compared with that of low back pain. Common causes of ulnar-sided wrist pain include triangular fibrocartilage complex injuries, lunotriquetral ligament injuries, and ulnar impaction syndrome.

Modern imaging of the hand, wrist, and forearm

A review of the current state of the relevant diagnostic imaging technologies and methods and their clinical application in imaging common conditions of the hand, wrist, and forearm is presented. Evolving and future imaging technologies are also considered.

Técnica e indicaciones de la resonancia magnética artrografía. Extremidad superior (I)

Magnetic resonance (MR) is the most effective imaging technique in the diagnosis of articular pathology. MR arthrography (MRA), with intra-articular injection of diluted gadolinium or physiological saline solution has become more common in recent years. The intra-articular fluid facilitates the detection of articular pathology by delineating the articular structures, separating adjacent anatomic structures, and filling potential spaces that originate in or communicate with the joint. MRA provides additional information about the integrity of the articular structures, especially cartilage, fibrocartilage, and ligaments. MRA has proven especially useful in the shoulder, where most of the studies have been centered. The detection of subtle lesions of the capsule/labrum complex is fundamental for presurgical evaluation. MRA can be used to complement conventional MR imaging in some cases and in others it is the initial technique of choice. Indirect MRA with intravenous gadolinium administration is based on the enhancement of articular fluid caused by diffusion from the synovial space to the articular space. This technique offers better results in articulations with less capacity for distension, such as the wrist, ankle, hand, and foot. This first part of two-part article reviews the current role of MRA in the upper limb. Special emphasis is placed on the shoulder joint, where its usefulness has been most clearly established. The usefulness of this technique in other joints is also described, reviewing the most important anatomic aspects, techniques and applications.

Imaging of Ulnar-Sided Wrist Pain

Ulnar-sided wrist pain has long been a diagnostic problem, partly because of the complex anatomy and many possible causes of pain in this region. This article discusses anatomy, pathophysiology, and imaging appearance of the more common causes, including tears of the triangular fibrocartilage complex, disorders of the distal radioulnar joint, tears of the lunotriquetral ligament, disorders of the extensor carpi ulnaris tendon, disorders of the pisotriquetral joint, the impingement and impaction syndromes, and ulnar wrist masses. Along with clinical history and physical examination, imaging is important in evaluation of ulnar-sided wrist pain. Conventional radiographs, conventional arthrography, CT, MRI, and MR arthrography are useful modalities that are often used in concert to help guide diagnosis and treatment.

Wrist MR Arthrography: How, Why, When

MR imaging of the wrist frequently represents a diagnostic challenge for radiologists because of the complex anatomy of this joint, small size of its components, and little known pathologic conditions. MR arthrography combines the advantages of conventional MR imaging and arthrography by improving the visualization of small intra-articular abnormalities. This article reviews the current role of MR arthrography in the evaluation of wrist joint disorders considering the relevant aspects of anatomy, techniques, and applications.