Magnetic resonance arthrography of the wrist: case presentation and discussion

Radio-carpal wrist MR arthrography: comparison of ultrasound with fluoroscopy and palpation-guided injections

OBJECTIVE

To compare ultrasound- (US), fluoroscopy- (FL), and palpation-guided contrast injection techniques used for dorsal radio-carpal wrist MRA.

MATERIALS AND METHODS

Patients with chronic wrist pain were randomized as to which injection technique they underwent into three groups of 50 participants. Dorsal radio-carpal contrast injection was performed under US, FL guidance (one radiologist for each), or palpation guidance by an orthopedic surgeon. The three techniques were compared by procedure time, success rate, number of attempts needed, frequency and grade of extravasation, joint distension, and MRA image quality. Additionally, any change from baseline wrist pain was recorded using the visual analog scale (VAS) at five time points (immediately, 8 h, 24 h, 48 h, and 1 week) after injection.

RESULTS

One hundred and fifty patients (83 males and 67 females; mean age 29 ± 6.5 years) were included. Success rates for US- and FL-guided injections were 100%, while palpation-guided approach was significantly less successful (72%) (P = 0.02) with significantly more frequent extravasation (56%)(P < 0.001). US guidance was the least time-consuming (6.5 ± 1.6 min) compared to FL guidance (12.5 ± 1.9 min) and palpation guidance (8 ± 1.2 min) (all P < 0.001). The mean number of joint puncture attempts was significantly lower with imaging-guided techniques (1.1 ± 0.24 and 1.2 ± 0.4 for US and FL, P = 0.23) compared to palpation-guided one (1.6 ± 0.8) (P = 0.007). The largest increases in baseline-pain were 8-h post-injection, and US guidance was the least painful at all-time points (all P < 0.05). Joint distension and image quality were significantly better with imaging-guided techniques (P < 0.001 and P = 0.003).

CONCLUSIONS

US-guided radio-carpal injection is a less time-consuming, more tolerable, and successful radiation-free method when compared to FL guidance. Palpation-guided injections require multiple attempts to enter the joint with high failure rates and frequent extravasation.

MRI of the Wrist Ligaments

Technological advances in magnetic resonance imaging (MRI) have improved radiologists' ability to evaluate wrist ligaments. MRI interpretation often guides clinical management. This article aims to review the normal and pathologic appearance of intrinsic and extrinsic wrist ligaments with a focus on MRI. Variant anatomy, imaging pearls, and clinical significance are also discussed. Special attention is paid to key wrist ligaments that play a role in carpal stability.

MR arthrography versus conventional MRI and diagnostic arthroscope in patients with chronic wrist pain

Objective

To assess the diagnostic accuracy of direct wrist MR arthrography (MRA) compared to conventional MRI in diagnosis of different pathologic entities causing chronic wrist pain.

Materials and methods

37 consecutive patients 22 males and 15 females, with age range from 16 to 49 years "mean age 28 years" complaining of unexplained chronic wrist pain were prospectively examined by using MRI and MRA with arthroscopic correlation in 25 of them. Findings were divided into 5 main groups of lesions including triangular fibrocartilage complex (TFCC) lesions, ligamentous injuries, osseous lesions, tendon pathology and ganglion.

Results

MRA picked up more ligamentous injuries and triangular fibrocartilage complex (TFCC) lesions that couldn`t be detected on MRI study while both were equal in detection of other types of lesions. TFCC lesions were the most common pathologic findings in both MRI and MRA. Arthroscopic correlation in 25 suspected TFCC lesions (clinically, radiologically or both) revealed that the sensitivity / specificity / accuracy of MRI and MRA were 87.5% / 100% / 96% and 100% / 100% / 100% respectively for central lesions while were 71.4% / 81.3% / 76% and 100% / 90.9% / 96% respectively For peripheral lesions. Extra-capsular lesions, like tenosynovitis and fracture hook of hamate couldn`t be confirmed arthroscopically.

Conclusion

MRA can replace both MRI and diagnostic arthroscopy in detecting causes of chronic wrist pain.

Radiological intervention of the hand and wrist

The role of radiological guided intervention is integral in the management of patients with musculoskeletal pathologies. The key to image-guided procedures is to achieve an accurately placed intervention with minimal invasion. This review article specifically concentrates on radiological procedures of the hand and wrist using ultrasound and fluoroscopic guidance. A systematic literature review of the most recent publications relevant to image-guided intervention of the hand and wrist was conducted. During this search, it became clear that there is little consensus regarding all aspects of image-guided intervention, from the technique adopted to the dosage of injectate and the specific drugs used. The aim of this article is to formulate an evidence-based reference point which can be utilized by radiologists and to describe the most commonly employed techniques.

Computed tomography arthrography using a radial plane view for the detection of triangular fibrocartilage complex foveal tears

PURPOSE

To classify triangular fibrocartilage complex (TFCC) foveal lesions on the basis of computed tomography (CT) arthrography using a radial plane view and to correlate the CT arthrography results with surgical findings. We also tested the interobserver and intra-observer reliability of the radial plane view.

METHODS

A total of 33 patients with a suspected TFCC foveal tear who had undergone wrist CT arthrography and subsequent surgical exploration were enrolled. We classified the configurations of TFCC foveal lesions into 5 types on the basis of CT arthrography with the radial plane view in which the image slices rotate clockwise centered on the ulnar styloid process. Sensitivity, specificity, and positive predictive values were calculated for each type of foveal lesion in CT arthrography to detect foveal tears. We determined interobserver and intra-observer agreements using kappa statistics. We also compared accuracies with the radial plane views with those with the coronal plane views.

RESULTS

Among the tear types on CT arthrography, type 3, a roundish defect at the fovea, and type 4, a large defect at the overall ulnar insertion, had high specificity and positive predictive value for the detection of foveal tears. Specificity and positive predictive values were 90% and 89% for type 3 and 100% and 100% for type 4, respectively, whereas sensitivity was 35% for type 3 and 22% for type 4. Interobserver and intra-observer agreement was substantial and almost perfect, respectively. The radial plane view identified foveal lesion of each palmar and dorsal radioulnar ligament separately, but accuracy results with the radial plane views were not statistically different from those with the coronal plane views.

CONCLUSIONS

Computed tomography arthrography with a radial plane view exhibited enhanced specificity and positive predictive value when a type 3 or 4 lesion was identified in the detection of a TFCC foveal tear compared with historical controls.

TYPE OF STUDY/LEVEL OF EVIDENCE

Diagnostic II.

MR arthrography of the wrist: controversies and concepts

Magnetic resonance arthrography (MRA) has become the preferred modality for imaging patients with internal derangement of the wrist. However, several aspects of MRA use need to be clarified before a standardized approach to the imaging of internal derangement of the wrist can be developed. The objective of the study is to evaluate the efficiency of different magnetic resonance (MR) sequences in the detection of lesions of the triangular fibrocartilage complex (TFCC) and scapholunate and lunotriquetral ligaments on direct MRA. Thirty-one consecutive direct magnetic resonance arthrographic examinations of the wrist using a wrist surface coil were performed for the assessment of the TFCC and intrinsic ligaments on a 1.5-T MR imaging system (Signa; 16 channel, Excite, GE Healthcare, Milwaukee, WI, USA). All patients had wrist pain, and in six cases, there was associated clinical carpal instability. The presence, location, and extent of TFCC, scapholunate ligament (SLL), and lunotriquetral ligament (LTL) lesions on T1 fat-saturated, multiplanar gradient recalled (MPGR) and short tau inversion recovery (STIR) images were identified, compared, and analyzed. Forty-one lesions of the TFCC, SLL, and LTL were visualized on contrast-sensitive (T1 fat-saturated) images in 23/31 (74.2%) patients. Twenty-one lesions of the TFCC and intrinsic ligaments were visualized on noncontrast-sensitive (MPGR and STIR) images (15 tears of the TFCC and six tears of the SLL and LTL). All of these lesions were seen on T1 fat-saturated images; 48.8% (20/41) lesions seen on T1 fat-saturated images (eight tears of TFCC and 12 tears of SLL and LTT) were not seen on MPGR and/or STIR images. Superior contrast resolution, joint distention, and the flow of contrast facilitate the diagnosis of lesions of the TFCC and intrinsic ligaments on contrast-sensitive sequences making MRA the preferred modality for imaging internal derangements of the wrist. Little agreement exists regarding the value and location of perforations of the intrinsic ligaments given that both traumatic and degenerative perforations may be symptomatic. Noncommunicating defects of the ulnar attachments of the triangular fibrocartilage (TFC), tears of the dorsal segment of the SLL, and defects at the lunate attachment of the SLL have a higher likelihood of being symptomatic and caused by trauma rather than by degenerative perforation. Although no consensus exists, it would appear that most arthrographies should be started with a radiocarpal injection. Injection into the distal radioulnar joint should be added if no communicational defects are visualized following radiocarpal injection in patients with ulnar-sided wrist pain.

A comparison of CT arthrography of the wrist to findings during wrist arthroscopy

PURPOSE

To determine the accuracy of computed tomography after wrist arthrogram (CT arthrogram) compared with findings during wrist arthroscopy as interpreted by a musculoskeletal radiologist and a board-certified hand surgeon.

METHODS

Seventy-six consecutive patients who had a wrist CT arthrogram and subsequent wrist arthroscopy were identified in the arthroscopic database of four hand surgeons working at a single institution between 2001 and 2006. Operative findings were obtained from the medical record. A single, blinded, musculoskeletal fellowship-trained radiologist prospectively read all CT arthrograms focusing on the following areas: scapholunate interosseous ligament (SLIL), lunotriquetral interosseous ligament (LTIL), peripheral and central triangular fibrocartilage complex (TFCC), and chondral surfaces. Computed tomography arthrograms were also read in a blinded, prospective fashion by a single hand surgeon. The results of both readings were compared with the findings at the time of wrist arthroscopy.

RESULTS

Sixteen SLIL tears, 29 LTIL tears, 10 peripheral TFCC tears, and 33 central TFCC tears were identified at the time of wrist arthroscopy. Sensitivity and specificity of the CT arthrogram were calculated using arthroscopy findings as our reference standard. The radiologist's readings (sensitivity, specificity) revealed the following: SLIL (94%, 86%), LTIL (85%, 79%), peripheral TFCC (30%, 94%), and central TFCC (88%, 95%). Results of CT arthrogram readings by the hand surgeon were SLIL (94%, 82%), LTIL (97%, 81%), peripheral TFCC (40%, 97%), and central TFCC (91%, 85%).

CONCLUSIONS

Computed tomography arthrogram of the wrist is highly accurate at detecting SLIL, LTIL, and central TFCC tears with high sensitivity and specificity. It is not as accurate at identifying peripheral tears.