Is MR better than arthrography for evaluating the ligaments of the wrist? In vitro study

High-resolution MRI (3T-MRI) in diagnosis of wrist pain: is diagnostic arthroscopy still necessary?

INTRODUCTION

3T MRI has become increasingly available for better imaging of interosseous ligaments, TFCC, and avascular necrosis compared with 1.5T MRI. This study assesses the sensitivity and specificity of 3T MRI compared with arthroscopy as the gold standard.

PATIENTS AND METHODS

Eighteen patients were examined with 3T MRI using coronal T1-TSE; PD-FS; and coronal, sagittal, and axial contrast-enhanced T1-FFE-FS sequences. Two musculoskeletal radiologists evaluated the images independently. Patients underwent diagnostic arthroscopy.

RESULTS

The classifications of the cartilage lesions showed good correlations with the arthroscopy findings (κ = 0.8-0.9). In contrast to the arthroscopy, cartilage of the distal carpal row was very good and could be evaluated in all patients on MRI. The sensitivity for the TFCC lesion was 83%, and the specificity was 42% (radiologist 1) and 63% (radiologist 2). For the ligament lesions, the sensitivity and specificity were 75 and 100%, respectively, with a high interobserver agreement (κ = 0.8-0.9).

DISCUSSION

3T MRI proved to be of good value in diagnosing cartilage lesions, especially in the distal carpal row, whereas wrist arthroscopy provided therapeutic options. When evaluating the surgical therapeutical options, 3T MRI is a good diagnostic tool for pre-operatively evaluating the cartilage of the distal carpal row.

Wrist Arthrography

The ligaments of the proximal row of carpal bones and the triangular fibrocartilage (TFC) strongly influence the function and stability of the wrist. Injury to the ligaments may result in chronic wrist pain or instability. Wrist arthrography is valuable in the investigation of such damage when surgical intervention is considered and plain radiography is unrewarding. There are also several technical modifications of the standard radiocarpal arthrography available. Owing to the possibility of congenital perforations and degenerative changes in these ligaments the arthrographic findings should be related to the clinical signs and the age of the patient. CT has less diagnostic importance in this respect while MR imaging is an alternative and may become the method of choice. Both these methods have great potential in the evaluation of soft tissues of the wrist other than the TFC.

Does High-Resolution MR Imaging Have Better Accuracy than Standard MR Imaging for Evaluation of the Triangular Fibrocartilage Complex?

We compared the findings of high-resolution MR imaging and standard MR imaging in the detection of tears of the triangular fibrocartilage in 33 patients with chronic wrist pain on the ulnar side. With arthroscopy as the standard of reference, sensitivity was 100%, specificity 53%, and accuracy 79% with the high-resolution MR imaging, against 83%, 67%, and 76% with the standard MR imaging. High-resolution MR imaging showed a higher sensitivity, but a decreased specificity in the assessment of the triangular fibrocartilage. The results showed that diagnosis of tears in the triangular fibrocartilage by MR imaging, even high-resolution MR imaging, is unsatisfactory, although further technological advances may well improve the accuracy.

Interosseous Ligament Tears of the Wrist: Comparison of Multi–Detector Row CT Arthrography and MR Imaging

PURPOSE

To compare the accuracy of multi-detector row computed tomographic (CT) arthrography and magnetic resonance (MR) imaging in depicting tears of dorsal, central, and palmar segments of scapholunate (SL) and lunotriquetral (LT) ligaments in cadavers.

MATERIALS AND METHODS

Cadaver wrists were obtained and used according to institutional guidelines and with informed consent of donors prior to death. Nine cadaver wrists of eight subjects were evaluated. MR images were obtained with a 1.5-T MR unit. Imaging protocol included intermediate-weighted coronal and transverse fast spin-echo and coronal three-dimensional gradient-echo sequences. Multi-detector row CT arthrography was performed after tricompartmental injection of 3-6 mL of contrast material with a concentration of 160 mg per milliliter of iodine. Palmar, dorsal, and central segments of both ligaments were analyzed on transverse and coronal MR images and multiplanar multi-detector row CT reconstructions by two musculoskeletal radiologists working independently. Open inspection of the wrists was the reference standard. Sensitivity, specificity, accuracy, and positive and negative predictive values were calculated from the imaging and gross pathologic readings. Statistical significance was calculated with the McNemar test. Weighted kappa values for interobserver agreement were calculated for both imaging modalities.

RESULTS

All ligament segments could be visualized in all cases with both imaging modalities. CT arthrography was more sensitive (100%) than MR imaging (60%) in detection of palmar segment tears (P = .62); specificity of both imaging modalities was 77%. Sensitivity (CT arthrography, 86%; MR imaging, 79%) and specificity (CT arthrography, 50%; MR imaging, 25%) for detection of the central segment tears were determined. Dorsal segment tears were detected only with CT arthrography, while all tears were missed with MR imaging (P = .02). Interobserver agreement was better for multi-detector row CT arthrography (kappa = 0.37-0.78) than for MR imaging (kappa = -0.33 to -0.10).

CONCLUSION

Performance in depiction of palmar and central segment tears of SL and LT ligaments is almost equal for multi-detector row CT arthrography and MR imaging, with much higher interobserver reliability for CT arthrography. CT arthrography is significantly superior to MR imaging in the detection of dorsal segment tears of SL and LT ligaments.

Treatment of Dynamic Scaphoid Instability

BACKGROUND

Chronic wrist pain attributable to scaphoid instability without fixed deformity (dynamic instability) presents a treatment dilemma. The diagnosis usually is delayed, missing the opportunity for direct repair. The intercarpal fusion, tenodesis, and capsulodesis procedures create a fixed deformity. This report presents an outcome study of a new treatment for dynamic scaphoid instability that spanned more than 5 years.

METHODS

Arthroscopic evaluation was used to confirm the diagnosis for 105 wrists of 102 patients who had experienced wrist pain for an average of 24.4 months. The treatment for these patients involved transferring two thirds of the extensor carpi radialis longus through the distal pole of the reduced scaphoid volarly to the intact flexor carpi radialis. The postoperative follow-up period averaged 63 months.

RESULTS

The average grip strength increased by 65%. The average active wrist extension-flexion increased by 9%, with an average radial deviation loss of 6 degrees. The overall results, as measured by the modified Green and O'Brien clinical wrist scale, were as follows: excellent (49%), good (24%), and fair (26%). Good to excellent results were reported by 85% of the patients. Pain relief was reported by 94% of the patients, and 93% of the patients would recommend the procedure to others.

CONCLUSIONS

Scaphoid instability without fixed deformity is a complex problem. Conventional treatments have drawbacks. The new technique produced positive results that are quite promising for the management of dynamic scaphoid instability.

The effect of observer experience on magnetic resonance imaging interpretation and localization of triangular fibrocartilage complex lesions

This study investigates the effect of experience of the interpreter on the ability of magnetic resonance imaging (MRI) to identify the presence and anatomic location of a triangular fibrocartilage complex (TFCC) lesion. Fifty-one patients who underwent wrist arthroscopy with preoperative MRI studies were reviewed retrospectively. Two radiologists with different levels of training and experience evaluated the MRI scans in a blinded manner. The sensitivity rates of the 2 observers for detection of TFCC lesions were 86% and 80%. The specificity rates were 96% and 80%. The accuracy rates for prediction of a TFCC tear were 83% and 61% for the 2 observers. The correct location of a TFCC lesion was predicted by the more experienced observer for 12 of 19 central, 3 of 4 radial, and 6 of 12 peripheral lesions. The less experienced observer correctly identified 8 of 19 central, 2 of 4 radial, and 2 of 12 peripheral tears. The overall accuracy rates for prediction of a TFCC lesion and its location were 69% and 37%. Our data indicate that the published accuracy rates for prediction of TFCC lesion location may be reproducible only in very specialized centers.

MRI versus arthroscopy in the diagnosis of scapholunate ligament injury

In a prospective study 103 patients with clinically or radiologically suspected tears of the scapholunate interosseous ligament were investigated with magnetic resonance imaging (MRI) and wrist arthroscopy. MRI was performed with the conventional technique in 72 cases and after intravenous injection of contrast medium in the remaining 31 patients. The correct diagnosis was made by MRI in 75% of cases and its overall sensitivity and specificity were 63% and 86% respectively. There was no statistical difference in the accuracy of MRI for acute or chronic tears and the use of intravenous contrast medium did not improve its accuracy. In conclusion, MRI is not recommended for the diagnosis of scapholunate ligament injury.

MRI of the wrist

In the past, the diagnostic imaging algorithm for evaluating the painful wrist included initial plain radiographic examination followed by arthrography, tomography, bone scintigraphy, or computed tomography. In recent years, magnetic resonance imaging (MRI) has been proven efficacious for diagnosing a number of maladies of the bones, ligaments, and soft tissues. MRI can be of aid in evaluation of carpal instability, disorders of the triangular fibrocartilage, ulnar impaction syndrome, distal radioulnar joint (DRUJ) instability, fracture, avascular necrosis (AVN), tendinopathy, nerve entrapment syndromes, synovial abnormalities, and soft tissue masses.

Characteristics of triangular fibrocartilage defects in symptomatic and contralateral asymptomatic wrists

PURPOSE

To characterize triangular fibrocartilage (TFC) defects in symptomatic and contralateral asymptomatic wrists.

MATERIALS AND METHODS

Communicating and noncommunicating defects of the TFC were depicted on bilateral wrist arthrograms in 56 patients with unilateral wrist pain and without associated lesions of the scapholunate or lunotriquetral ligaments. The exact location of each TFC lesion was noted.

RESULTS

Communicating defects were noted in 36 (64%) of 56 symptomatic and in 26 (46%) of 56 asymptomatic wrists. Twenty-five (69%) of 36 communicating defects were bilateral. Except for one defect in each group of symptomatic and asymptomatic wrists, all communicating defects were noted radially. Noncommunicating defects were noted in 28 (50%) of 56 symptomatic wrists and in 15 (27%) of 56 asymptomatic wrists. Eleven (39%) of 28 noncommunicating defects were bilateral. On the symptomatic side, 28 of 36 noncommunicating defects (including eight multiple defects) were located proximally at the ulnar side. On the asymptomatic side, 11 of 17 noncommunicating defects (including two multiple defects) were at or near the ulna.

CONCLUSION

Noncommunicating TFC defects, which typically are located on the proximal side of the TFC near its ulnar attachment, have a more reliable association with symptomatic wrists than do communicating defects. Radial-sided communicating defects described in the literature (Palmer type 1A and 1D) as posttraumatic commonly are seen bilaterally and in asymptomatic wrists.

Clinical Applications of Magnetic Resonance Imaging in the Hand and Wrist for Soft Tissue and Ligamentous Injuries

With advances in magnetic resonance imaging (MRI) technology and observer experience, MRI is an established part of the diagnostic work-up for soft tissue injuries of the hand and wrist. It potentially minimizes the need for invasive procedures such as arthrography or arthroscopy. However, there are limitations of MRI, and many patients who undergo MRI of the wrist still need wrist arthroscopy for both diagnostic and therapeutic purposes. A review of the recent literature of the role of MRI in the assessment of soft tissue injuries of the hand and wrist is presented.

Wrist arthrography after acute trauma to the distal radius: diagnostic accuracy, technique, and sources of diagnostic errors

RATIONALE AND OBJECTIVES

The objective of this investigation was to determine the diagnostic accuracy of wrist arthrography in the detection of interosseous ligament disruptions and of triangular fibrocartilage complex (TFCC) lesions in patients after acute wrist trauma and to define the sources of diagnostic error of wrist arthrography after recent trauma.

METHODS

Twenty-two patients with radial fractures after acute wrist trauma underwent arthrography and arthroscopy of the wrist. Arthrography was performed in a standardized manner by two- or three-compartment injection technique. Subsequently wrist arthroscopy was performed within the same session. Image analysis included the evaluation of interosseous carpal ligaments, the TFCC, and the osseous structures.

RESULTS

In 22 patients, 11 injuries of the intrinsic ligaments and the TFCC were diagnosed by arthroscopy, of which 9 had been diagnosed correctly with arthrography before surgery. One scaphoid fracture previously missed on conventional radiographs also could be diagnosed by arthrography.

CONCLUSION

Arthrography of the posttraumatic wrist is a valuable tool in the diagnostic evaluation of interosseous carpal ligaments and the TFCC.

Triangular fibrocartilage and intercarpal ligaments of the wrist: does MR arthrography improve standard MRI?

The objective of this study was to assess the value of adding MR arthrography to standard MRI for patients with chronic wrist disorders. Thirty consecutive patients (age range, 19-73 years; mean, 36.2 years) were included in the investigation. The images were evaluated blindly and separately by two radiologists with regard to lesions of the scapholunate (SL) and lunotriquetral (LT) ligaments and the triangular fibrocartilage (TFC). Conventional two- or three-compartment arthrography was used as the standard of reference. For TFC lesions, standard MR images had a sensitivity of 92.3% (reader 1) and 84.6% (reader 2) and a specificity of 41.2% (reader 1) and 52.9% (reader 2). For MR arthrography, sensitivity was 84.6% (reader 1) and 84.6% (reader 2) and specificity was 88.2% (reader 1) and 100% (reader 2). For SL ligament tears, standard MRI had a sensitivity of 33.3% (reader 1) and 11.1% (reader 2) and a specificity of 47.6% (reader 1) and 57.1% (reader 2). For MR arthrography, sensitivity was 66.7% (reader 1) and 55.6% (reader 2) and specificity was 52.4% (reader 1) and 81.0% (reader 2). For LT ligament tears, standard MRI had a sensitivity of 28.6% (reader 1) and 35.7% (reader 2) and a specificity of 93.8% (reader 1) and 81.3% (reader 2). For MR arthrography, sensitivity was 35.7% (reader 1) and 23.1% (reader 2) and specificity was 93.8% (reader 1) and 94.1% (reader 2). In conclusion, the diagnostic performance of MRI in suspected lesions of the TFC and the SL and LT ligaments is improved by adding MR arthrography to the standard examination.

Magnetic resonance imaging of the musculoskeletal system. Part 5. The wrist

Musculoskeletal radiology has been transformed with the advent of magnetic resonance imaging. Magnetic resonance imaging provides visualization of the complex anatomy of the wrist and delineation of numerous pathologic processes, which are difficult to visualize with conventional imaging modalities. With the use of sophisticated pulse sequences and a dedicated extremity coil, magnetic resonance imaging allows evaluation of osseous and ligamentous injuries, arthritides, tumors, and tumor-like conditions. Magnetic resonance imaging techniques will be emphasized and anatomy and various pathologic conditions pertaining to the wrist will be reviewed.

MR imaging of ulnar impaction

The ulnar impaction syndrome of the wrist is a well-recognized clinical entity, usually showing distinct radiographic features including a positive ulnar variance and degenerative subchondral changes of the distal ulna, proximal lunate, and proximal triquetrum. Confirmation of the clinical and plain film findings with advanced imaging is often necessary to exclude other entities with a similar clinical presentation. Although arthrography and bone scintigraphy are helpful in this work-up, magnetic resonance imaging (MRI) appears to be both a sensitive and a specific means of evaluation. The imaging studies in four patients with clinically and surgically diagnosed ulnar impaction are described, with emphasis on MRI findings. MRI appears to be the modality of choice in the evaluation of patients with suspected ulnolunate impingement.

Magnetic resonance imaging of the wrist

As improvements in surface coil technology and imaging sequences continue, increased applicability of MRI to small yet complex structures such as the wrist is assured. Almost certainly, the full potential of MRI in the wrist has yet to be realized, and its versatility is perhaps limited only by the radiologist's experience. As we become more adept at this modality, it will become an increasingly important component in the radiology armamentarium.

Magnetic resonance imaging of the anterior radiocarpal ligaments

Magnetic resonance imaging was applied to eight cadaver wrists to evaluate the efficacy of imaging the anterior radiocarpal ligaments. In order to verify a correlation between the magnetic resonance images and anatomic structures, ancillary studies using gadolinium-DTPA ligamentography and gross sectioning of the specimens were performed. The ligaments targeted for evaluation were the radioscaphocapitate, long radiolunate, and short radiolunate ligaments. The highest resolution images were obtained using a 1.5 Tesla magnetic resonance imaging scanner and a surface coil applied to the wrist region, and producing T1-weighted images, with 3 mm thick sections with an 8 cm field of view. The radioscaphocapitate, long radiolunate, and short radiolunate ligaments were most consistently identified in sagittal planes, however they were also identified in coronal planes. The radioscapholunate ligament and the interosseous ligaments between the scaphoid, lunate, and triquetrum were most consistently identified in coronal planes. Transaxial planes provided consistently inferior views, and should be reserved for imaging of the flexor and extensor retinaculae.

Proximal wrist imaging

Ligamentous injuries to the triangular fibrocartilage are often difficult to evaluate. The plain film examination along with the physical examination serves as the basis for the initial assessment of most wrist injuries. Ligamentous injuries of the wrist often present at the subacute or chronic state with the physical examination and plain films being insufficient to make a definitive diagnosis in many cases and the plain film radiographic exam being of little additional value. This paper reviews the triangular fibrocartilage complex including the underlying anatomy and biomechanics, along with its radiographic evaluation by modern imaging techniques.

An algorithm for acute wrist trauma. A systematic approach to diagnosis

A systematic approach to the acute traumatized wrist is of importance to achieve early diagnosis, with efficient use of advanced imaging modalities. In a 6-month period 641 patients aged 15 years or over were examined using an algorithm for acute wrist trauma in order to secure early and appropriate treatment. In 293 (46%) cases routine radiographic examination supplied sufficient information to establish a fracture diagnosis. All 33 scaphoid fractures (including five scaphoid non-unions) were demonstrated on the initial X-ray examination. In 56 patients (9%) scintigraphy proved useful for selecting cases in need of further radiographic examination. Among 31 patients with focal activity on bone scintigraphy, CT and/or tomography revealed eight distal radial fractures, one fracture of the ulnar styloid, and eight fractures of carpal bones. Fractures were revealed using tomography and/or "hot spot views" in patients with negative CT examinations suggesting that further examinations should be performed in cases with increased focal activity on bone scintigraphy and a negative CT examination.

[The diagnostic value of arthrography of the wrist in the evaluation of carpal ligament injuries: radio-surgical correlations. Apropos of 20 cases]

Intra-carpal ligament tears lead to radiocarpal arthritis early diagnosis allows early treatment. Standard and dynamic X rays are not always able to make the diagnosis. In these cases, arthrography of the wrist may give the diagnosis. To establish the specificity of this examination we tried to correlate surgical findings with arthrographic suspicions. Exact diagnosis was established in 12 out of 13 cases of suspected scapholunate ligament tears in 5 out of 6 cases of suspected luno-triquetral ligament tear suspicion and none of the 3 cases of suspected T.F.C.C. rupture suspicion. Wrist arthrography appears to have a good specificity for first row intra-carpal ligament tears. The indication arthrography must be discussed with wrist arthroscopy for the diagnosis of long term wrist pain after clinical examination and standard and dynamic X rays.

Magnetic resonance imaging of tendon and ligament abnormalities: Part I. Spine and upper extremities

Magnetic resonance imaging (MRI) has proven to be an ideal technique for evaluating tendons and ligaments, which, because of their fibrous structure, have a low signal intensity on all sequences. Trauma and a wide variety of other conditions cause aberrations in the normal appearance of these structures, ranging from minor alterations in shape, size, appearance, and continuity to various changes in signal intensity within the tendon, tendon sheath, and ligament on different sequences. The purpose of this paper is to review MRI findings in patients with abnormalities of tendons and ligaments in the spine and upper extremities.

High-resolution fast low-angle shot magnetic resonance imaging of the normal hand

Cross-sectional magnetic resonance (MR) images of the normal hand, wrist, and fingers with an inplane resolution of 0.2-0.4 mm and a slice thickness of 1-2 mm were obtained using a 40-cm bore, 2.35-T MRI system equipped with actively shielded 50 mT m-1 gradient coils. A detailed description of the normal anatomy is given. The T1-weighted, multi-slice, fast low-angle shot (FLASH) MR images presented show a substantial improvement in resolution as compared with earlier reports. Typical investigational times of about 15 min offer a fast scan protocol that is suitable for routine clinical applications. The study further demonstrates the potential of dedicated magnets to facilitate and refine diagnostic MR imaging of hand injuries and hand-related diseases.