Scapholunate Advanced Collapse and Scaphoid Nonunion Advanced Collapse: MDCT Arthrography Features

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1 Musculoskeletal Imaging Pictorial Essay Crema et al. MDCT rthrography of SLC and SNC Musculoskeletal Imaging Pictorial Essay Michel D. Crema 1,2 Joachim Zentner 3 li Guermazi 1 Nabil Jomaah 4 Monica D. Marra 1 Frank W. Roemer 1,3 Crema MD, Zentner J, Guermazi, Jomaah N, Marra MD, Roemer FW Keywords: arthritis, arthrography, dorsal intercalated segment instability (DISI), MDCT, scaphoid nonunion advanced collapse, scapholunate advanced collapse, scapholunate ligament, wrist DOI: /JR Received July 15, 2011; accepted after revision November 7, M. D. Crema is a shareholder in oston Imaging Core Lab (ICL).. Guermazi is the president of ICL and is a consultant to Merck Serono, Stryker, Novartis, Genzyme, and strazeneca. M. D. Marra and F. W. Roemer are shareholders in ICL. 1 Department of Radiology, Quantitative Imaging Center, oston University School of Medicine, 820 Harrison ve, FGH ldg, 3rd Fl, oston, M ddress correspondence to M. D. Crema (michelcrema@gmail.com). 2 Department of Radiology, Hospital do Coração (HCor) and Teleimagem, São Paulo, razil. 3 Department of Radiology, Klinikum ugsburg, ugsburg, Germany. 4 Department of Radiology, SPETR, Doha, Qatar. WE This is a Web exclusive article. JR 2012; 199:W202 W X/12/1992 W202 merican Roentgen Ray Society Scapholunate dvanced Collapse and Scaphoid Nonunion dvanced Collapse: MDCT rthrography Features OJECTIVE. The aim of this article is to present the imaging features of scapholunate advanced collapse (SLC) and scaphoid nonunion advanced collapse (SNC) on MDCT arthrography. CONCLUSION. MDCT arthrography is an excellent tool for patients with clinically suspected SLC or SNC wrist because it allows identification of the spectrum of findings for diagnosis and proper classification, which directly impact management. S capholunate advanced collapse (SLC) is the most common type of degenerative arthritis in the wrist [1]. Traumatic scapholunate ligament injury is the leading cause of SLC wrist [2]. Other causes include Kienböck disease, chondrocalcinosis [3], and other carpal fractures. The scapholunate interosseous ligament bonds the scaphoid and the lunate. The dorsal component of the scapholunate ligament is the most critical of the scapholunate stabilizers [4] because it is the thickest and strongest component. The volar component of the scapholunate ligament is thinner and adds to rotational stability of the scapholunate joint. The membranous (proximal) component of the scapholunate ligament contributes little to scapholunate joint stability. The mechanism of scapholunate ligament injury is axial overload or hyperextension with carpal supination or ulnar deviation. In addition, scapholunate ligament insufficiency may occur as a residual of perilunate injury [5]. static increase in the scapholunate interval (scapholunate dissociation) and dorsiflexion of the lunate occur as a consequence of a complete tear of the scapholunate ligament associated with a tear of one or more extrinsic ligaments [6]. In addition, rotatory subluxation (volar flexion) of the scaphoid occurs, and further dorsal and proximal translation of the capitate along with the distal carpal row will lead to a dorsal intercalated segment instability (DISI) deformity [7]. DISI causes abnormal articular loading that leads to the degenerative changes known as SLC wrist. Scaphoid nonunion secondary to fracture may lead to a similar pattern of instability, including DISI deformity. The abnormal loading and progression of degenerative changes are similar to those in SLC and are known as scaphoid nonunion advanced collapse (SNC). The aim of this article is to present the specific degenerative patterns of SLC and SNC on MDCT arthrography. MDCT rthrography MDCT arthrography is a powerful tool for the detection of traumatic and degenerative lesions in the wrist joint [8]. MDCT arthrography is equivalent to MR arthrography in the detection of internal wrist abnormalities and injuries, so it is an ideal alternative when MR arthrography is contraindicated or MRI is not available [9 12]. Our standardized protocol consists of a double or triple injection of iodine contrast material (ioxaglate meglumine [Hexabrix 320, Guerbet]) under fluoroscopic guidance (Fig. 1). single injection may suffice when communication of the three compartments is observed during fluoroscopy after the first injection. High-resolution 64-MDCT (Somatom Sensation, Siemens Healthcare) of the wrist and forearm in the neutral position is performed using the following parameters: 0.4-mm slice thickness, 0.2-mm gap, 120 kv, 200 m, pitch of 0.9, 144-mm FOV, and 75f reconstruction kernel. Reconstruction in the axial, sagittal, and coronal planes is performed (1.5-mm slice thickness, 1.5-mm gap, 144-mm FOV). The normal appearances of the radiocarpal and midcarpal joints on MDCT arthrography are shown in Figure 2. W202 JR:199, ugust 2012

2 MDCT rthrography of SLC and SNC Scapholunate Ligament Tear and Dorsal Intercalated Segment Instability Deformity MDCT arthrography accurately depicts partial or complete tears of the scapholunate ligament. xial images are useful to evaluate partial or complete tears of the dorsal and volar components (Fig. 3). Coronal images are useful to evaluate tears of the membranous (proximal) component (Fig. 4). DISI can be evaluated on MDCT using sagittal images, where the axis of the scaphoid, lunate, and capitate may be determined (Fig. 5). For exact angle measurement, neutral positioning that is, neither pronated nor supinated of the wrist is paramount. s a result of scaphoidal volar flexion and lunate dorsiflexion, the scapholunate angle is increased (normal angle, ). The capitolunate angle is also increased (normal angle, 0 30 ) because of the lunate dorsiflexion. Scapholunate dvanced Collapse Wrist and Scaphoid Nonunion dvanced Collapse Wrist Stage I The first sign of SLC and SNC wrist is chondromalacia limited to the radial styloidscaphoid joint (Figs. 6 and 7). Subchondral bone sclerosis with or without cystic formation also may be seen. t this stage, the proximal radioscaphoid, scaphocapitate, and capitolunate joints are intact. In SLC, the scapholunate ligament is disrupted and communication between the radiocarpal and midcarpal joints is seen. In SNC, the scapholunate ligament may be intact and communication between the radiocarpal and midcarpal joints may occur through the scaphoid nonunion. Stage II Progression is observed as additional wear or as chondromalacia with degenerative changes depicted in the whole radioscaphoid joint (Figs. 8 and 9). Degenerative subchondral changes may also be detected. t this stage, the scaphocapitate and capitolunate joints are still intact. Stage III The last stage represents further degeneration: evidence of degenerative changes in the scaphocapitate or capitolunate joints with cartilage loss and degenerative subchondral changes (Figs. 10 and 11). Proximal displacement of the capitate is part of the late spectrum of SLC and SNC. Osteophytosis may be pronounced in this stage. Treatment There is no evidence of long-term success of conservative management of SLC or SNC wrist [13]. For chronic DISI deformity without gross degenerative changes in the wrist, limited intercarpal arthrodesis is indicated [14, 15]. Proximal row carpectomy is often reserved for patients with stage I or II SLC and SNC. Excision of the scaphoid with fusion of the capitate, hamate, lunate, and triquetrum also known as four-corner arthrodesis is another surgical option for SLC or SNC wrist [8]. SNC wrist has the additional option of excision of the distal scaphoid fragment. References 1. Watson HK, allet FL. The SLC wrist: scapholunate advanced collapse pattern of degenerative arthritis. J Hand Surg m 1984; 9: Kuo CE, Wolfe SW. Scapholunate instability: current concepts in diagnosis and management. J Hand Surg m 2008; 33: Chen C, Chandnani VP, Kang HS, Resnick D, Sartoris DJ, Haller J. Scapholunate advanced collapse: a common wrist abnormality in calcium pyrophosphate dihydrate crystal deposition disease. Radiology 1990; 177: erger R, Imeada T, erglund L, n KN. Constraint and material properties of the subregions of the scapholunate interosseous ligament. J Hand Surg m 1999; 24: Mayfield JK, Johnson RP, Kilcoyne RK. Carpal dislocations: pathomechanics and progressive perilunar instability. J Hand Surg m 1980; 5: Meade TD, Schneider LH, Cherry K. Radiographic analysis of selective ligament sectioning at the carpal scaphoid: a cadaver study. J Hand Surg m 1990; 15: Linscheid RL, Dobyns JH, eabout JW, ryan RS. Traumatic instability of the wrist: diagnosis, classification, and pathomechanics. J one Joint Surg m 1972; 54: Moser T, Dosch JC, Moussaoui, uy X, Gangi, Dietemann JL. Multidetector CT arthrography of the wrist joint: how to do it. RadioGraphics 2008; 28: ; quiz, ille, Harley, Cohen H. comparison of CT arthrography of the wrist to findings during wrist arthroscopy. J Hand Surg m 2007; 32: Omlor G, Jung M, Grieser T, Ludwig K. Depiction of the triangular fibro-cartilage in patients with ulnar-sided wrist pain: comparison of direct multi-slice CT arthrography and direct MR arthrography. Eur Radiol 2009; 19: Schmid MR, Schertler T, Pfirrmann CW, et al. Interosseous ligament tears of the wrist: comparison of multi-detector row CT arthrography and MR imaging. Radiology 2005; 237: Moser T, Dosch JC, Moussaoui, Dietemann JL. Wrist ligament tears: evaluation of MRI and combined MDCT and MR arthrography. JR 2007; 188: Strauch RJ. Scapholunate advanced collapse and scaphoid nonunion advanced collapse arthritis: update on evaluation and treatment. J Hand Surg m 2011; 36: Peterson H, Lipscomb PR. Intercarpal arthrodesis. rch Surg 1967; 95: Pisano SM, Peimer C, Wheeler DR, Sherwin F. Scaphocapitate intercarpal arthrodesis. J Hand Surg m 1991; 16: JR:199, ugust 2012 W203

3 Crema et al. Fig. 1 Diagram of wrist. rthrographic technique involves up to three injections (X) of contrast material. First injection of contrast material is in radiocarpal joint (green) next to proximal articular surface of scaphoid (S); second injection is in midcarpal joint (blue) in space between capitate (C), hamate (H), lunate (L), and triquetrum (T); and, if necessary, third injection is in distal radioulnar joint (yellow) next to radial surface of ulnar head (U). Fig. 2 Normal anatomy of wrist on MDCT arthrography of 42-year-old man after triplecompartment injection., Coronal view shows normal aspect of membranous components of scapholunate (white arrow) and lunotriquetral (black arrow) ligaments as well as triangular fibrocartilage (asterisk). Note normal chondral morphology at radial (R), scaphoid (S), lunate (L), and capitate (C) articular surfaces. No communication is seen between midcarpal, radiocarpal, and distal radioulnar joints., xial view reveals dorsal (D) and volar (V) components of scapholunate ligament (arrows) are intact because no contrast filling is seen within these components. Fig. 3 Scapholunate ligament tear., xial MDCT arthrographic image of 62-year-old man after receiving double-compartment injection shows large complete tear of both dorsal (D) and volar (V) components of ligament (arrows). Tear allows communication between midcarpal and radiocarpal joints., xial MDCT arthrographic image of 53-year-old woman after receiving double-compartment injection shows complete tear at dorsal (D) component of scapholunate ligament (arrow) with intact volar (V) component (arrowheads). W204 JR:199, ugust 2012

4 MDCT rthrography of SLC and SNC Fig. 4 Tear of membranous component of scapholunate ligament in 56-year-old woman. Coronal MDCT arthrographic image obtained after double-compartment injection shows tear at level of membranous component of ligament (arrow) that has led to abnormal communication between midcarpal and radiocarpal joints. Fig. 5 Dorsal intercalated segment instability (DISI) in 62-year-old man. D = dorsal, V = volar., Sagittal MDCT arthrographic image shows dorsiflexion of lunate, with increased capitolunate angle (> 30 ). L = lunate axis, C = capitate axis., Sagittal MDCT arthrographic image shows volar flexion of scaphoid, with increased scapholunate angle (> 60 ). S = scaphoid axis, L = lunate axis (reproduced as in ). Fig. 6 Stage I of scapholunate advanced collapse (SLC) in wrist., Drawing shows stage I SLC wrist: chondromalacia with subchondral marrow changes in radial styloid-scaphoid joint (arrowheads). Subchondral marrow changes may be absent. Note tearing of membranous component of scapholunate ligament (arrow). t this stage, proximal radioscaphoid, scaphocapitate, and capitolunate joints are intact. R = radius, S = scaphoid, L = lunate, C = capitate., Stage I SLC wrist in 40-year-old man. Coronal MDCT arthrographic image obtained after double-compartment injection shows cartilage thinning adjacent to radial styloid articular surface (arrowheads). No significant subchondral marrow changes are depicted. Note tearing of membranous component of scapholunate ligament (arrow) and scapholunate dissociation with communication between radiocarpal and midcarpal joints. C, xial MDCT arthrographic image of same patient as in shows complete tear of both dorsal (D) and volar (V) components of scapholunate ligament (arrows). C JR:199, ugust 2012 W205

5 Crema et al. Fig. 7 Stage I of scaphoid nonunion advanced collapse (SNC) in wrist of 42-year-old man. Coronal MDCT arthrographic image obtained after doublecompartment injection shows scaphoid nonunion without contrast filling of fracture (white arrow). Sclerosis of proximal pole of scaphoid indicates necrosis. Note also central pinhole in proximal pole of scaphoid. There is cartilage thinning adjacent to radial styloid-scaphoid joint (arrowheads). Proximal radioscaphoid, scaphocapitate, and capitolunate joints are intact. Note intact membranous component of scapholunate ligament (black arrow). Fig. 9 Stage II of scaphoid nonunion advanced collapse (SNC) in wrist of 52-year-old man. Coronal MDCT arthrographic image obtained after double-compartment injection shows scaphoid nonunion with contrast filling of fracture gap (white arrows) has led to communication between radiocarpal and midcarpal joints. There is cartilage thinning of entire radioscaphoid joint (arrowheads). Note intact membranous component of scapholunate ligament (black arrow). Fig. 10 Stage III of scapholunate advanced collapse (SLC) in wrist., Drawing shows stage III SLC wrist: chondromalacia with subchondral marrow changes in entire radioscaphoid (black arrowheads) and capitolunate (white arrowheads) joints. Subchondral marrow changes may be absent. Note tearing at membranous component of scapholunate ligament (arrow). R = radius, S = scaphoid, L = lunate, C = capitate., Stage III SLC wrist in 55-year-old man. Coronal MDCT arthrographic image obtained after double-compartment injection shows marked cartilage thinning and subchondral sclerosis of radioscaphoid (white arrowheads) and capitolunate (black arrowheads) articular surfaces. Note tearing at level of membranous component of scapholunate ligament (arrow) and scapholunate dissociation with communication between radiocarpal and midcarpal joints. (Fig. 10 continues on next page) Fig. 8 Stage II of scapholunate advanced collapse (SLC)., Drawing shows stage II SLC wrist: chondromalacia with subchondral marrow changes in whole radioscaphoid joint (arrowheads). Subchondral marrow changes may be absent. Note tearing of membranous component of scapholunate ligament (arrow). t this stage, scaphocapitate and capitolunate joints are intact. R = radius, S = scaphoid, L = lunate, C = capitate., Stage II SLC wrist in 65-year-old man. Coronal MDCT arthrographic image obtained after doublecompartment injection shows cartilage thinning of entire radioscaphoid articular surface and subchondral sclerosis (arrowheads). Note tearing of membranous component of scapholunate ligament (arrow) and scapholunate dissociation with communication between radiocarpal and midcarpal joints. W206 JR:199, ugust 2012

6 MDCT rthrography of SLC and SNC C D Fig. 10 (continued) Stage III of scapholunate advanced collapse (SLC) in wrist. C, xial MDCT arthrographic image of same patient shown in reveals complete tear of dorsal (D) component (arrow) and partial tear of volar (V) component (arrowheads) of scapholunate ligament. D, Sagittal MDCT arthrographic image of same patient shown in and C depicts cartilage thinning and subchondral sclerosis at dorsal aspect of capitolunate joint (arrowheads). Fig. 11 Stage III of scaphoid nonunion advanced collapse (SNC) in wrist of 50-year-old man. Coronal MDCT arthrographic image obtained after triple-compartment injection shows scaphoid nonunion without contrast filling of fracture (arrows). There is cartilage thinning and subchondral sclerosis adjacent to radioscaphoid (black arrowheads) and scaphocapitate (white arrowheads) articular surfaces. Note intact membranous component of scapholunate ligament. JR:199, ugust 2012 W207