The ulnotriquetral ligament is one of the intracapsular extrinsic palmar ulnocarpal ligaments and a component of the ulnocarpal complex 1-4.
The ulnotriquetral ligament forms the anterior and ulnar part of the ulnocarpal joint capsule together with the ulnolunate ligament, with which it shares a common origin and connects the volar radioulnar ligament and thus the triangular fibrocartilage complex to the triquetral bone 1-3.
Distally the ulnotriquetral ligament fans out and inserts broadly onto the palmar proximal and ulnar cortex of the triquetral bone 1-4.
The ulnotriquetral ligament features often a pisotriquetral and prestyloid orifice and variable distal attachments to the styloid process 1.
The ulnotriquetral ligament can be visualized on ultrasound with the transducer placed at the volar ulnar aspect of the wrist in the longitudinal plane. The long axis of the ligament is then displayed as an echogenic, fibrillary structure coursing over the ulnocarpal joint and connecting the volar radioulnar ligament to the triquetrum. Proximally it cannot be demarcated from the ulnolunate ligament 2,3.
The ulnotriquetral ligament can be visualized on MRI best on coronal or 3D images 4. With proper anatomical knowledge, it can be also variably seen on sagittal images. It has a hypointense, striated appearance and is seen anterior to the medial ulnocarpal joint.
The ligament is most likely injured or involved in the following pathologic conditions 6-8:
- traumatic triangular fibrocartilage complex injury
- ulnar-sided perilunate 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. 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
- 6. Oneson SR, Scales LM, Timins ME, Erickson SJ, Chamoy L. MR imaging interpretation of the Palmer classification of triangular fibrocartilage complex lesions. (1996) Radiographics : a review publication of the Radiological Society of North America, Inc. 16 (1): 97-106. doi:10.1148/radiographics.16.1.97 - Pubmed
- 7. von Borstel D, Wang M, Small K, Nozaki T, Yoshioka H. High-Resolution 3T MR Imaging of the Triangular Fibrocartilage Complex. (2017) Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine. 16 (1): 3-15. doi:10.2463/mrms.rev.2016-0011 - Pubmed
- 8. Murray PM, Palmer CG, Shin AY. The mechanism of ulnar-sided perilunate instability of the wrist: a cadaveric study and 6 clinical cases. (2012) The Journal of hand surgery. 37 (4): 721-8. doi:10.1016/j.jhsa.2012.01.015 - Pubmed