The radioscaphocapitate ligament is one of the intracapsular, extrinsic palmar radiocarpal ligaments and a volar stabilizer of the wrist 1-3.
The radioscaphocapitate ligament connects the palmar surface of the distal radius with the scaphoid and the capitate bone, running in an oblique orientation and composes the radial and a part of the volar radiocarpal joint capsule 1-4. It runs adjacent to the long radiolunate ligament, separated by the interligament sulcus. Together with the ulnocapitate ligament, it forms the palmar greater arc or arcuate ligament 2,3.
The proximal insertion or origin of the radioscaphocapitate ligament is located in the volar area from the radial styloid process to the middle of the scaphoid fossa 1-3.
It covers and stabilizes the waist of the scaphoid bone like a sling and connects to the proximal surface of the distal pole. From there, fibers run to the palmar surface of the capitate bone, where they insert after blending with fibers from the ulnocapitate and scaphotriquetral and volar scaphotrapeziotrapezoid ligaments 1-5.
The radioscaphocapitate ligament can be visualized on ultrasound with the transducer placed at the volar aspect of the radial side of the slightly extended wrist in the longitudinal plane and then rotated towards the capitate bone. The long axis of the ligament is displayed as a fibrillary structure attaching the distal radius to the scaphoid and capitate bone 2,3.
The radioscaphocapitate ligament is easily seen on MRI. It can be best appreciated on coronal, sagittal or 3D images and usually shows a hypointense, striated appearance. The interligament sulcus, which separates the radioscaphocapitate ligament from medially adjacent and more proximally coursing long radiolunate ligament, can be delineated as a fluid intense structure.
The ligament is most likely injured or involved in the following pathologic conditions 7,8:
- nondissociative carpal instability (CIND)
- ulnar translocation (type 1): rheumatoid arthritis, Madelung deformity
- radial translocation
- radiocarpal translocation
- midcarpal instability (MCI)
- dorsal midcarpal instability
- 1. Berger RA. The anatomy of the ligaments of the wrist and distal radioulnar joints. (2001) Clinical orthopaedics and related research. doi:10.1097/00003086-200102000-00006 - Pubmed
- 2. Gitto S, Draghi F. Normal Sonographic Anatomy of the Wrist With Emphasis on Assessment of Tendons, Nerves, and Ligaments. (2016) Journal of ultrasound in medicine : official journal of the American Institute of Ultrasound in Medicine. 35 (5): 1081-94. doi:10.7863/ultra.15.06105 - Pubmed
- 3. Taljanovic MS, Goldberg MR, Sheppard JE, Rogers LF. US of the intrinsic and extrinsic wrist ligaments and triangular fibrocartilage complex--normal anatomy and imaging technique. (2011) Radiographics : a review publication of the Radiological Society of North America, Inc. 31 (1): e44. doi:10.1148/rg.e44 - Pubmed
- 4. Bateni CP, Bartolotta RJ, Richardson ML, Mulcahy H, Allan CH. Imaging key wrist ligaments: what the surgeon needs the radiologist to know. (2013) AJR. American journal of roentgenology. 200 (5): 1089-95. doi:10.2214/AJR.12.9738 - Pubmed
- 5. Timins ME, Jahnke JP, Krah SF, Erickson SJ, Carrera GF. MR imaging of the major carpal stabilizing ligaments: normal anatomy and clinical examples. (1995) Radiographics : a review publication of the Radiological Society of North America, Inc. 15 (3): 575-87. doi:10.1148/radiographics.15.3.7624564 - Pubmed
- 6. Rominger MB, Bernreuter WK, Kenney PJ, Lee DH. MR imaging of anatomy and tears of wrist ligaments. (1993) Radiographics : a review publication of the Radiological Society of North America, Inc. 13 (6): 1233-46; discussion 1247-8. doi:10.1148/radiographics.13.6.8290721 - Pubmed
- 7. Aita MA, Alves RS, Ibanez DS, Consoni DAP, de Oliveira RK, Ruggiero GM. Reconstruction of Radioscaphocapitate Ligament in Treatment of Ulnar Translation. (2019) Journal of wrist surgery. 8 (2): 147-151. doi:10.1055/s-0038-1668559 - Pubmed
- 8. Khan M, Lim WY, Resnick D. Carpal Instability. MRI Web Clinic - June 2012 Radsource - MRI Web Clinic - June 2012