DOI: 10.1148/rg.264055114
Pathologic Conditions of the Hypothenar Eminence: Evaluation with Multidetector CT and MR Imaging1
Alain G. Blum, MD, PhD,
Jean-Philippe Zabel, MD,
Romain Kohlmann, MD,
Toufik Batch, MD,
Karine Barbara, MD,
Xavier Zhu, MD,
Gilles Dautel, MD, PhD and
François Dap, MD, PhD
1 From the Service d’Imagerie Guilloz, CHU Nancy, Avenue de Lattre de Tassigny, Nancy 54000, France (A.G.B., J.P.Z., R.K., T.B., K.B., X.Z.); and Service de chirurgie plastique et reconstructive de l’appareil locomoteur, Hôpital Jeanne d’Arc, CHU Nancy, Nancy, France (G.D., F.D.). Recipient of a Certificate of Merit award for an education exhibit at the 2004 RSNA Annual Meeting. Received May 6, 2005; revision requested July 6 and received January 12, 2006; accepted February 20. All authors have no financial relationships to disclose.
View larger version (106K):
[in a new window]
|
Figure 1. Schematic of the pisotriquetral complex shows the soft-tissue attachments from which the pisiform bone derives its stability. The bone is covered completely by tendinous insertions of the flexor carpi ulnaris (FCU) and the abductor digiti minimi (ADM) muscles. It provides sites of attachment on its radial side for the flexor retinaculum (FR); on its ulnar side, for the extensor retinaculum (ER); and on its distal side, for the pisohamate (PH) and pisometacarpal (PM) ligaments. In addition, a tough but loose fibrous capsule connects the pisiform bone to the triquetrum.
|
|
View larger version (148K):
[in a new window]
|
Figure 2a. MR images of the pisotriquetral complex. (a) Sagittal T1-weighted image shows the flexor carpi ulnaris tendon (black arrow), the pisometacarpal ligament (white arrow), and the abductor digiti minimi muscle (1). (b) Sagittal T1-weighted image shows the pisohamate ligament (arrow). (c) Coronal T1-weighted image shows the pisohamate ligament (arrow) and the abductor digiti minimi (1) and flexor digiti minimi (2) muscles. H = hamatum, h = hamulus, M5 = fifth metacarpal bone, P = pisiform bone, T = triquetrum, U = ulna.
|
|
View larger version (157K):
[in a new window]
|
Figure 2b. MR images of the pisotriquetral complex. (a) Sagittal T1-weighted image shows the flexor carpi ulnaris tendon (black arrow), the pisometacarpal ligament (white arrow), and the abductor digiti minimi muscle (1). (b) Sagittal T1-weighted image shows the pisohamate ligament (arrow). (c) Coronal T1-weighted image shows the pisohamate ligament (arrow) and the abductor digiti minimi (1) and flexor digiti minimi (2) muscles. H = hamatum, h = hamulus, M5 = fifth metacarpal bone, P = pisiform bone, T = triquetrum, U = ulna.
|
|
View larger version (153K):
[in a new window]
|
Figure 2c. MR images of the pisotriquetral complex. (a) Sagittal T1-weighted image shows the flexor carpi ulnaris tendon (black arrow), the pisometacarpal ligament (white arrow), and the abductor digiti minimi muscle (1). (b) Sagittal T1-weighted image shows the pisohamate ligament (arrow). (c) Coronal T1-weighted image shows the pisohamate ligament (arrow) and the abductor digiti minimi (1) and flexor digiti minimi (2) muscles. H = hamatum, h = hamulus, M5 = fifth metacarpal bone, P = pisiform bone, T = triquetrum, U = ulna.
|
|
View larger version (131K):
[in a new window]
|
Figure 3. The pisotriquetral joint. Sagittal CT arthrogram of the wrist shows a large superior recess (red arrow) and a smaller inferior recess (yellow arrow) after a contrast medium injection in the radiocarpal joint.
|
|
View larger version (121K):
[in a new window]
|
Figure 4a. Axial T1-weighted MR images of the Guyon canal. (a) At the inlet of the canal, the ulnar nerve (green arrow) is seen just deep to the radial aspect of the flexor carpi ulnaris (black arrow), on the ulnar side of the ulnar veins (blue arrows) and ulnar artery (red arrow). (b) The proximal end of the canal, at the level of the pisiform bone, corresponds to zone 1. Here the cross-sectional shape of the canal is generally triangular, with the base of the triangle directed toward the pisiform bone (P). The canal is delimited ulnarly by the pisiform bone, posteriorly by the ligamentum flexorum (white arrowheads), and anteriorly by the ligamentum carpi palmare (black arrowheads). The ulnar nerve and its branches (green arrows) lie between the pisiform bone and the flexor carpi ulnaris tendon (black arrow) on the ulnar side and the ulnar veins and artery (red arrow) on the radial side. (c) At its middle, between the pisiform bone and the hamulus, the canal appears triangular or ovoid in cross section. Note the appearance of the abductor digiti minimi muscle (1), the ulnar artery (red arrow), and the bifurcation of the ulnar nerve into superficial (yellow arrow) and deep (green arrow) branches. (d, e) Zones 2 and 3 (at the level of the hamulus and just below it) are clearly identifiable in the distal portion of the canal. The flexor digiti minimi (2 in e) and the opponens digiti minimi (3 in e) are apparent. Zone 2 contains the deep motor branch (green arrow in d) of the ulnar nerve and its branches (green arrowheads in e) and the deep branch of the ulnar artery (red arrowhead). Note the pisometacarpal ligament (white arrow in d) on the ulnar side of the base of the hamulus. Zone 3 contains the superficial sensory branches (yellow arrows) of the ulnar nerve.
|
|
View larger version (120K):
[in a new window]
|
Figure 4b. Axial T1-weighted MR images of the Guyon canal. (a) At the inlet of the canal, the ulnar nerve (green arrow) is seen just deep to the radial aspect of the flexor carpi ulnaris (black arrow), on the ulnar side of the ulnar veins (blue arrows) and ulnar artery (red arrow). (b) The proximal end of the canal, at the level of the pisiform bone, corresponds to zone 1. Here the cross-sectional shape of the canal is generally triangular, with the base of the triangle directed toward the pisiform bone (P). The canal is delimited ulnarly by the pisiform bone, posteriorly by the ligamentum flexorum (white arrowheads), and anteriorly by the ligamentum carpi palmare (black arrowheads). The ulnar nerve and its branches (green arrows) lie between the pisiform bone and the flexor carpi ulnaris tendon (black arrow) on the ulnar side and the ulnar veins and artery (red arrow) on the radial side. (c) At its middle, between the pisiform bone and the hamulus, the canal appears triangular or ovoid in cross section. Note the appearance of the abductor digiti minimi muscle (1), the ulnar artery (red arrow), and the bifurcation of the ulnar nerve into superficial (yellow arrow) and deep (green arrow) branches. (d, e) Zones 2 and 3 (at the level of the hamulus and just below it) are clearly identifiable in the distal portion of the canal. The flexor digiti minimi (2 in e) and the opponens digiti minimi (3 in e) are apparent. Zone 2 contains the deep motor branch (green arrow in d) of the ulnar nerve and its branches (green arrowheads in e) and the deep branch of the ulnar artery (red arrowhead). Note the pisometacarpal ligament (white arrow in d) on the ulnar side of the base of the hamulus. Zone 3 contains the superficial sensory branches (yellow arrows) of the ulnar nerve.
|
|
View larger version (126K):
[in a new window]
|
Figure 4c. Axial T1-weighted MR images of the Guyon canal. (a) At the inlet of the canal, the ulnar nerve (green arrow) is seen just deep to the radial aspect of the flexor carpi ulnaris (black arrow), on the ulnar side of the ulnar veins (blue arrows) and ulnar artery (red arrow). (b) The proximal end of the canal, at the level of the pisiform bone, corresponds to zone 1. Here the cross-sectional shape of the canal is generally triangular, with the base of the triangle directed toward the pisiform bone (P). The canal is delimited ulnarly by the pisiform bone, posteriorly by the ligamentum flexorum (white arrowheads), and anteriorly by the ligamentum carpi palmare (black arrowheads). The ulnar nerve and its branches (green arrows) lie between the pisiform bone and the flexor carpi ulnaris tendon (black arrow) on the ulnar side and the ulnar veins and artery (red arrow) on the radial side. (c) At its middle, between the pisiform bone and the hamulus, the canal appears triangular or ovoid in cross section. Note the appearance of the abductor digiti minimi muscle (1), the ulnar artery (red arrow), and the bifurcation of the ulnar nerve into superficial (yellow arrow) and deep (green arrow) branches. (d, e) Zones 2 and 3 (at the level of the hamulus and just below it) are clearly identifiable in the distal portion of the canal. The flexor digiti minimi (2 in e) and the opponens digiti minimi (3 in e) are apparent. Zone 2 contains the deep motor branch (green arrow in d) of the ulnar nerve and its branches (green arrowheads in e) and the deep branch of the ulnar artery (red arrowhead). Note the pisometacarpal ligament (white arrow in d) on the ulnar side of the base of the hamulus. Zone 3 contains the superficial sensory branches (yellow arrows) of the ulnar nerve.
|
|
View larger version (118K):
[in a new window]
|
Figure 4d. Axial T1-weighted MR images of the Guyon canal. (a) At the inlet of the canal, the ulnar nerve (green arrow) is seen just deep to the radial aspect of the flexor carpi ulnaris (black arrow), on the ulnar side of the ulnar veins (blue arrows) and ulnar artery (red arrow). (b) The proximal end of the canal, at the level of the pisiform bone, corresponds to zone 1. Here the cross-sectional shape of the canal is generally triangular, with the base of the triangle directed toward the pisiform bone (P). The canal is delimited ulnarly by the pisiform bone, posteriorly by the ligamentum flexorum (white arrowheads), and anteriorly by the ligamentum carpi palmare (black arrowheads). The ulnar nerve and its branches (green arrows) lie between the pisiform bone and the flexor carpi ulnaris tendon (black arrow) on the ulnar side and the ulnar veins and artery (red arrow) on the radial side. (c) At its middle, between the pisiform bone and the hamulus, the canal appears triangular or ovoid in cross section. Note the appearance of the abductor digiti minimi muscle (1), the ulnar artery (red arrow), and the bifurcation of the ulnar nerve into superficial (yellow arrow) and deep (green arrow) branches. (d, e) Zones 2 and 3 (at the level of the hamulus and just below it) are clearly identifiable in the distal portion of the canal. The flexor digiti minimi (2 in e) and the opponens digiti minimi (3 in e) are apparent. Zone 2 contains the deep motor branch (green arrow in d) of the ulnar nerve and its branches (green arrowheads in e) and the deep branch of the ulnar artery (red arrowhead). Note the pisometacarpal ligament (white arrow in d) on the ulnar side of the base of the hamulus. Zone 3 contains the superficial sensory branches (yellow arrows) of the ulnar nerve.
|
|
View larger version (114K):
[in a new window]
|
Figure 4e. Axial T1-weighted MR images of the Guyon canal. (a) At the inlet of the canal, the ulnar nerve (green arrow) is seen just deep to the radial aspect of the flexor carpi ulnaris (black arrow), on the ulnar side of the ulnar veins (blue arrows) and ulnar artery (red arrow). (b) The proximal end of the canal, at the level of the pisiform bone, corresponds to zone 1. Here the cross-sectional shape of the canal is generally triangular, with the base of the triangle directed toward the pisiform bone (P). The canal is delimited ulnarly by the pisiform bone, posteriorly by the ligamentum flexorum (white arrowheads), and anteriorly by the ligamentum carpi palmare (black arrowheads). The ulnar nerve and its branches (green arrows) lie between the pisiform bone and the flexor carpi ulnaris tendon (black arrow) on the ulnar side and the ulnar veins and artery (red arrow) on the radial side. (c) At its middle, between the pisiform bone and the hamulus, the canal appears triangular or ovoid in cross section. Note the appearance of the abductor digiti minimi muscle (1), the ulnar artery (red arrow), and the bifurcation of the ulnar nerve into superficial (yellow arrow) and deep (green arrow) branches. (d, e) Zones 2 and 3 (at the level of the hamulus and just below it) are clearly identifiable in the distal portion of the canal. The flexor digiti minimi (2 in e) and the opponens digiti minimi (3 in e) are apparent. Zone 2 contains the deep motor branch (green arrow in d) of the ulnar nerve and its branches (green arrowheads in e) and the deep branch of the ulnar artery (red arrowhead). Note the pisometacarpal ligament (white arrow in d) on the ulnar side of the base of the hamulus. Zone 3 contains the superficial sensory branches (yellow arrows) of the ulnar nerve.
|
|
View larger version (117K):
[in a new window]
|
Figure 5. Volume-rendered CT angiogram of the ulnar artery and collateral circulation in the hand shows a classic configuration of the superficial palmar arch (2), the deep palmar branch of the ulnar artery (1), the supply to the thumb (3), and the superficial palmar branch of the radial artery (4). h = hamulus, P = pisiform bone, RA = radial artery, UA = ulnar artery.
|
|
View larger version (143K):
[in a new window]
|
Figure 6. Axial T1-weighted MR image shows an accessory abductor digiti minimi muscle (arrow).
|
|
View larger version (136K):
[in a new window]
|
Figure 7. Radially deviated, thumb-abducted lateral radiographic view depicts a hamate fracture (arrow). This view is obtained with a 2-cm prop placed under the forearm; the forearm is in neutral (true lateral) position or is slightly supinated, the thumb is maximally abducted and extended, and the hand is maximally radially deviated. The x-ray beam is centered on the web between the thumb and the index finger so that the hamulus (h) lies in the center of the beam and there is no superimposed bone. P = pisiform bone.
|
|
View larger version (164K):
[in a new window]
|
Figure 8a. Pisiform bone fracture not depicted on posteroanterior and lateral radiographs. (a) Semisupinated oblique radiographic view depicts the pisiform bone fracture. (b) Axial CT scan helps confirm the diagnosis and rules out any other bone lesion.
|
|
View larger version (88K):
[in a new window]
|
Figure 8b. Pisiform bone fracture not depicted on posteroanterior and lateral radiographs. (a) Semisupinated oblique radiographic view depicts the pisiform bone fracture. (b) Axial CT scan helps confirm the diagnosis and rules out any other bone lesion.
|
|
View larger version (151K):
[in a new window]
|
Figure 9a. Osteochondral fracture of the pisiform bone in a 35-year-old man after a fall on his outstretched right hand. At physical examination, there was acute pain during palpation over the bone. Posteroanterior and lateral radiographic views were normal. (a) Semisupinated oblique radiographic view depicts an irregularity of the subchondral bone of the pisiform and two small bone fragments (arrows) highly suggestive of loose bodies in the inferior pisotriquetral joint recess. (b) Sagittal gadolinium-enhanced T1-weighted fat-saturated MR image depicts two small osteochondral fragments (arrows) in the inferior pisotriquetral joint recess, a bruise of the pisiform bone, and subchondral bone marrow edema in the triquetrum.
|
|
View larger version (125K):
[in a new window]
|
Figure 9b. Osteochondral fracture of the pisiform bone in a 35-year-old man after a fall on his outstretched right hand. At physical examination, there was acute pain during palpation over the bone. Posteroanterior and lateral radiographic views were normal. (a) Semisupinated oblique radiographic view depicts an irregularity of the subchondral bone of the pisiform and two small bone fragments (arrows) highly suggestive of loose bodies in the inferior pisotriquetral joint recess. (b) Sagittal gadolinium-enhanced T1-weighted fat-saturated MR image depicts two small osteochondral fragments (arrows) in the inferior pisotriquetral joint recess, a bruise of the pisiform bone, and subchondral bone marrow edema in the triquetrum.
|
|
View larger version (100K):
[in a new window]
|
Figure 10. Pisiform bone dislocation and distal radial fracture in a 49-year-old woman after a fall on her outstretched hand. CT scan shows widening of the pisotriquetral joint space (small white arrow), a severe pisotriquetral joint effusion without osteochondral fragments, a hematoma deep in the midcarpal space (black arrows), and palmar displacement of the Guyon canal (large white arrow). Dislocation of the pisiform bone and a complete tear of the ligamentum carpi palmare were confirmed at surgery.
|
|
View larger version (104K):
[in a new window]
|
Figure 11a. Triquetral fracture in a 40-year-old man with chronic pain at the ulnar side of the wrist and over the hypothenar eminence 2 months after a fall on his outstretched left hand. Posteroanterior radiography showed a lateral fracture of the triquetrum. Also depicted was a positive ulnar variance, with the distal projection of the ulnar articular surface exceeding that of the radial articular surface. CT arthrograms show an osteochondral fracture of the triquetrum (white arrow) and a distal tear of the triangular fibrocartilage complex (yellow arrow in b). Also evident are signs of ulnar impaction syndrome, including a large central tear of the triangular fibrocartilage complex (red arrowheads in b) and severe chondromalacia of the lunate bone (white arrowhead in b).
|
|
View larger version (156K):
[in a new window]
|
Figure 11b. Triquetral fracture in a 40-year-old man with chronic pain at the ulnar side of the wrist and over the hypothenar eminence 2 months after a fall on his outstretched left hand. Posteroanterior radiography showed a lateral fracture of the triquetrum. Also depicted was a positive ulnar variance, with the distal projection of the ulnar articular surface exceeding that of the radial articular surface. CT arthrograms show an osteochondral fracture of the triquetrum (white arrow) and a distal tear of the triangular fibrocartilage complex (yellow arrow in b). Also evident are signs of ulnar impaction syndrome, including a large central tear of the triangular fibrocartilage complex (red arrowheads in b) and severe chondromalacia of the lunate bone (white arrowhead in b).
|
|
View larger version (175K):
[in a new window]
|
Figure 12. Posteroanterior radiograph in a case of hamulus fracture shows the absence of the hook of the hamate.
|
|
View larger version (161K):
[in a new window]
|
Figure 13a. Nonunion with avascular necrosis of the hamulus. (a) Posteroanterior radiograph shows a sclerotic hamulus. (b) Axial CT scan helps confirm nonunion and necrosis of the hamulus (arrow).
|
|
View larger version (94K):
[in a new window]
|
Figure 13b. Nonunion with avascular necrosis of the hamulus. (a) Posteroanterior radiograph shows a sclerotic hamulus. (b) Axial CT scan helps confirm nonunion and necrosis of the hamulus (arrow).
|
|
View larger version (106K):
[in a new window]
|
Figure 14. Fracture of the hook of the hamate in a 40-year-old woman with pain over the hook and tenosynovitis of the fifth finger. Sagittal T2-weighted fast spin-echo (SE) MR image shows a fracture in the base of the hook (black arrow) and soft-tissue edema along the flexor digitorum profundus tendon of the fifth finger (white arrow). No tendon tear or compression of the ulnar nerve was noted.
|
|
View larger version (102K):
[in a new window]
|
Figure 15. Fracture of the hamulus apex detected at radiography in a 53-year-old woman with paresthesia of the fourth and fifth fingers while gripping an object. Axial T2-weighted fat-saturated fast SE MR image shows bone marrow edema of the hamulus as well as close contact between the hamulus and the superficial branch of the ulnar nerve (arrow).
|
|
View larger version (101K):
[in a new window]
|
Figure 16. Tenosynovitis of the fifth-finger flexor tendons and an os hamuli proprium in a 51-year-old man with diffuse wrist pain. Axial gadolinium-enhanced T1-weighted MR image shows the triangular os hamuli proprium (white arrow) and the flexor tendons between the body of the hamate (H) and the os hamuli proprium. Note the synovial enhancement in the tendon sheath (black arrow).
|
|
View larger version (101K):
[in a new window]
|
Figure 17. Axial CT scan shows calcific tendonitis of the flexor carpi ulnaris tendon (arrow) in a 28-year-old woman.
|
|
View larger version (110K):
[in a new window]
|
Figure 18a. Severe flexor carpi ulnaris tendonitis in a 50-year-old woman with paresthesia in the fourth and fifth fingers. Axial gadolinium-enhanced T1-weighted fat-saturated SE MR images demonstrate severe peritenon inflammation (arrow in a) that extends to the ulnar nerve (arrow in b) in the Guyon canal. Note, however, that a ghost artifact due to pulsation of the ulnar artery (arrowhead in b) makes analysis of the flexor carpi ulnaris enthesis difficult.
|
|
View larger version (104K):
[in a new window]
|
Figure 18b. Severe flexor carpi ulnaris tendonitis in a 50-year-old woman with paresthesia in the fourth and fifth fingers. Axial gadolinium-enhanced T1-weighted fat-saturated SE MR images demonstrate severe peritenon inflammation (arrow in a) that extends to the ulnar nerve (arrow in b) in the Guyon canal. Note, however, that a ghost artifact due to pulsation of the ulnar artery (arrowhead in b) makes analysis of the flexor carpi ulnaris enthesis difficult.
|
|
View larger version (98K):
[in a new window]
|
Figure 19a. Recurrent synovitis of the fifth-finger flexor tendons in a 28-year-old man 1 year after surgical synovectomy of the carpal tunnel and Guyon canal. Results of serologic tests and cultures were negative. The patient presented with pain over the Guyon canal and paresthesia in the fourth and fifth fingers; other joints were normal. Axial gadolinium-enhanced T1-weighted fat-saturated MR images at the level of the hook of the hamate (a) and the metacarpal bone (b) show medial dislocation and tenosynovitis of the fifth-finger flexor tendon (black arrow) and medial displacement of the superficial branch of the ulnar nerve (white arrow in a), which is trapped between the hamulus and the flexor tendon.
|
|
View larger version (78K):
[in a new window]
|
Figure 19b. Recurrent synovitis of the fifth-finger flexor tendons in a 28-year-old man 1 year after surgical synovectomy of the carpal tunnel and Guyon canal. Results of serologic tests and cultures were negative. The patient presented with pain over the Guyon canal and paresthesia in the fourth and fifth fingers; other joints were normal. Axial gadolinium-enhanced T1-weighted fat-saturated MR images at the level of the hook of the hamate (a) and the metacarpal bone (b) show medial dislocation and tenosynovitis of the fifth-finger flexor tendon (black arrow) and medial displacement of the superficial branch of the ulnar nerve (white arrow in a), which is trapped between the hamulus and the flexor tendon.
|
|
View larger version (100K):
[in a new window]
|
Figure 20a. Osteoarthritis secondary to loose bodies in the pisotriquetral joint. (a) Semisupinated oblique radiographic view reveals severe degeneration of the pisotriquetral joint in association with two loose bodies. (b) Sagittal gadolinium-enhanced three-dimensional fast spoiled gradient-echo MR image with fat suppression shows the two loose bodies (arrows), one located in the superior recess and the other in the inferior recess, surrounded by high-signal-intensity halos indicative of a severe synovial reaction. P = pisiform bone.
|
|
View larger version (125K):
[in a new window]
|
Figure 20b. Osteoarthritis secondary to loose bodies in the pisotriquetral joint. (a) Semisupinated oblique radiographic view reveals severe degeneration of the pisotriquetral joint in association with two loose bodies. (b) Sagittal gadolinium-enhanced three-dimensional fast spoiled gradient-echo MR image with fat suppression shows the two loose bodies (arrows), one located in the superior recess and the other in the inferior recess, surrounded by high-signal-intensity halos indicative of a severe synovial reaction. P = pisiform bone.
|
|
View larger version (126K):
[in a new window]
|
Figure 21. Primary osteoarthritis with loose bodies in a 45-year-old woman with pain in the ulnar side of the wrist. Posteroanterior and semisupinated oblique radiographic views showed two large loose bodies in the superior recess of the pisotriquetral joint but no joint space narrowing. Radiocarpal arthrography failed to show communication of the radiocarpal compartment with the pisotriquetral joint, but a supinated oblique view obtained after a direct injection of contrast medium into the joint space enabled the identification of loose bodies in the superior recess (arrow). An intra-articular injection of corticosteroids led to temporary relief of pain (for 3 months), and the patient was able to undergo surgical repair. At the 6-month follow-up examination, clinical results were satisfactory.
|
|
View larger version (111K):
[in a new window]
|
Figure 22a. Osteoarthritis secondary to a synovial cyst of the pisotriquetral joint in a 37-year-old woman with ulnar-sided wrist pain. Posteroanterior and lateral radiographs were normal, and the semisupinated oblique view showed only moderate osteoarthritis. Conventional (a) and CT (b) arthrograms show a synovial cyst (arrow in a) that extends from the superior recess of the pisotriquetral joint. Cartilage lesions of the pisiform and the triquetrum are found mostly on the ulnar side of the articular surface (arrowheads in b).
|
|
View larger version (103K):
[in a new window]
|
Figure 22b. Osteoarthritis secondary to a synovial cyst of the pisotriquetral joint in a 37-year-old woman with ulnar-sided wrist pain. Posteroanterior and lateral radiographs were normal, and the semisupinated oblique view showed only moderate osteoarthritis. Conventional (a) and CT (b) arthrograms show a synovial cyst (arrow in a) that extends from the superior recess of the pisotriquetral joint. Cartilage lesions of the pisiform and the triquetrum are found mostly on the ulnar side of the articular surface (arrowheads in b).
|
|
View larger version (102K):
[in a new window]
|
Figure 23. Ganglion cyst with compression of the motor branch of the ulnar nerve in an 18-year-old woman. Coronal T2-weighted fast SE image shows a synovial cyst (black arrow) that compresses the deep branch of the ulnar nerve (arrowhead). Note the normal appearance of the ulnar nerve (white arrow) along the pisiform bone (P), before its division.
|
|
View larger version (85K):
[in a new window]
|
Figure 24a. Hypothenar hammer syndrome in a 48-year-old man with acute pain and a tender mass in the hypothenar eminence and with paresthesia of the fourth and fifth fingers. (a, b) Axial CT image (a) and coronal three-dimensional volume-rendered CT image (b) show an occluded aneurysm of the ulnar artery (arrow). (c) Axial T1-weighted MR image shows an area of high signal intensity in the vessel lumen, a finding indicative of an occluded ulnar artery aneurysm (arrow).
|
|
View larger version (103K):
[in a new window]
|
Figure 24b. Hypothenar hammer syndrome in a 48-year-old man with acute pain and a tender mass in the hypothenar eminence and with paresthesia of the fourth and fifth fingers. (a, b) Axial CT image (a) and coronal three-dimensional volume-rendered CT image (b) show an occluded aneurysm of the ulnar artery (arrow). (c) Axial T1-weighted MR image shows an area of high signal intensity in the vessel lumen, a finding indicative of an occluded ulnar artery aneurysm (arrow).
|
|
View larger version (137K):
[in a new window]
|
Figure 24c. Hypothenar hammer syndrome in a 48-year-old man with acute pain and a tender mass in the hypothenar eminence and with paresthesia of the fourth and fifth fingers. (a, b) Axial CT image (a) and coronal three-dimensional volume-rendered CT image (b) show an occluded aneurysm of the ulnar artery (arrow). (c) Axial T1-weighted MR image shows an area of high signal intensity in the vessel lumen, a finding indicative of an occluded ulnar artery aneurysm (arrow).
|
|
View larger version (91K):
[in a new window]
|
Figure 25. Hypothenar hammer syndrome in a 47-year-old man, a manual worker and smoker with fourth-digit coolness and cold intolerance. Three-dimensional volume-rendered CT image demonstrates a small fusiform aneurysm of the ulnar artery (open arrow) at the level of the hamulus, a segmental occlusion in the superficial palmar arch (solid arrow), a corkscrew configuration of the superficial palmar arch (arrowhead), and occlusion of the lateral digital artery of the fifth finger.
|
|
View larger version (94K):
[in a new window]
|
Figure 26. Ganglion cyst in a 46-year-old man with hypothenar eminence pain. Standard radiographs were normal. Coronal T2-weighted fast SE image depicts a cyst with a pedicle (arrow) that links it to the pisotriquetral joint.
|
|
View larger version (98K):
[in a new window]
|
Figure 27a. Schwannoma of the ulnar nerve in a 54-year-old woman. Axial T2-weighted fat-saturated fast SE image (a) and axial gadolinium-enhanced T1-weighted fat-saturated SE image (b) show an ovoid tumor of the ulnar nerve with central and peripheral enhancement.
|
|
View larger version (99K):
[in a new window]
|
Figure 27b. Schwannoma of the ulnar nerve in a 54-year-old woman. Axial T2-weighted fat-saturated fast SE image (a) and axial gadolinium-enhanced T1-weighted fat-saturated SE image (b) show an ovoid tumor of the ulnar nerve with central and peripheral enhancement.
|
|
View larger version (132K):
[in a new window]
|
Figure 28a. Low-flow mixed vascular malformation of the hypothenar eminence in a 34-year-old man. Coronal T1-weighted image (a) and axial T2-weighted fat-saturated fast SE image (b) show a large mass that has infiltrated the hypothenar muscles. No phleboliths are evident.
|
|
View larger version (83K):
[in a new window]
|
Figure 28b. Low-flow mixed vascular malformation of the hypothenar eminence in a 34-year-old man. Coronal T1-weighted image (a) and axial T2-weighted fat-saturated fast SE image (b) show a large mass that has infiltrated the hypothenar muscles. No phleboliths are evident.
|
|
View larger version (93K):
[in a new window]
|
Figure 29a. Recurrent low-flow mixed vascular malformation of the hypothenar eminence in a 21-year-old man. (a) Axial T2-weighted fat-saturated fast SE image shows a large hyperintense mass that has infiltrated the hypothenar muscles and contains areas of thrombosis (arrow). (b) Three-dimensional volume-rendered image from multidetector CT in the venous phase shows the slow filling of the dilated vascular spaces and a surgical clip. MR angiograms and CT images showed no enhancement of the lesion in the arterial phase.
|
|
View larger version (112K):
[in a new window]
|
Figure 29b. Recurrent low-flow mixed vascular malformation of the hypothenar eminence in a 21-year-old man. (a) Axial T2-weighted fat-saturated fast SE image shows a large hyperintense mass that has infiltrated the hypothenar muscles and contains areas of thrombosis (arrow). (b) Three-dimensional volume-rendered image from multidetector CT in the venous phase shows the slow filling of the dilated vascular spaces and a surgical clip. MR angiograms and CT images showed no enhancement of the lesion in the arterial phase.
|
|
View larger version (102K):
[in a new window]
|
Figure 30a. Vascular malformation in a 54-year-old woman with tenderness in the hypothenar eminence. Axial source image (a), maximum intensity projection image (b), and three-dimensional volume-rendered image (c) from multidetector CT angiography show a dilated serpentine ulnar artery that, along with the medial palmar branch and the superficial palmar arch, feeds a high-flow vascular malformation.
|
|
View larger version (53K):
[in a new window]
|
Figure 30b. Vascular malformation in a 54-year-old woman with tenderness in the hypothenar eminence. Axial source image (a), maximum intensity projection image (b), and three-dimensional volume-rendered image (c) from multidetector CT angiography show a dilated serpentine ulnar artery that, along with the medial palmar branch and the superficial palmar arch, feeds a high-flow vascular malformation.
|
|
View larger version (74K):
[in a new window]
|
Figure 30c. Vascular malformation in a 54-year-old woman with tenderness in the hypothenar eminence. Axial source image (a), maximum intensity projection image (b), and three-dimensional volume-rendered image (c) from multidetector CT angiography show a dilated serpentine ulnar artery that, along with the medial palmar branch and the superficial palmar arch, feeds a high-flow vascular malformation.
|
|
View larger version (135K):
[in a new window]
|
Figure 31a. Typical intramuscular lipoma in a 43-year-old man. Coronal T1-weighted image (a) and axial gadolinium-enhanced T1-weighted fat-saturated image (b) show a well-demarcated homogeneous fatty mass in the flexor digiti minimi muscle (arrow). Note the absence of contrast enhancement in the mass in b.
|
|
View larger version (87K):
[in a new window]
|
Figure 31b. Typical intramuscular lipoma in a 43-year-old man. Coronal T1-weighted image (a) and axial gadolinium-enhanced T1-weighted fat-saturated image (b) show a well-demarcated homogeneous fatty mass in the flexor digiti minimi muscle (arrow). Note the absence of contrast enhancement in the mass in b.
|
|
View larger version (114K):
[in a new window]
|
Figure 32a. Osteoid osteoma of the pisiform bone in a 26-year-old woman with diffuse hypothenar eminence pain that increased with activity and at night and decreased slightly with aspirin therapy. (a) CT scan depicts a small nidus (arrow) in the pisiform bone. (b) Axial gadolinium-enhanced T1-weighted fat-saturated image shows bone marrow edema of the pisiform bone (P), pisotriquetral joint effusion, and soft-tissue inflammation in the flexor carpi ulnaris tendon (black arrow) and along the medial side of the ulnar nerve (white arrow) in the Guyon canal.
|
|
View larger version (114K):
[in a new window]
|
Figure 32b. Osteoid osteoma of the pisiform bone in a 26-year-old woman with diffuse hypothenar eminence pain that increased with activity and at night and decreased slightly with aspirin therapy. (a) CT scan depicts a small nidus (arrow) in the pisiform bone. (b) Axial gadolinium-enhanced T1-weighted fat-saturated image shows bone marrow edema of the pisiform bone (P), pisotriquetral joint effusion, and soft-tissue inflammation in the flexor carpi ulnaris tendon (black arrow) and along the medial side of the ulnar nerve (white arrow) in the Guyon canal.
|
|
Copyright © 2006 by the Radiological Society of North America.
