Radial collateral ligament of the wrist

The radial collateral ligament or radioscaphoid ligament is one of the intracapsular, extrinsic radiocarpal ligaments and a radial stabilizer of the wrist ^1-3.

Gross anatomy

The radial collateral ligament connects the radial styloid process with the scaphoid running in a fan-shaped, fairly longitudinal orientation forming the most radial part of the radiocarpal joint capsule. It is located deep to abductor pollicis longus and extensor pollicis brevis tendons ^1-6.

Attachments

The proximal insertion or origin of the radial collateral ligament is the radial styloid process, radially and slightly dorsally located to the origin of the radioscaphocapitate ligament ^1-3.

The radial collateral ligament inserts distally at the radial surface of the scaphoid bone ^1-5.

Radiographic features

Ultrasound

The radial collateral ligament can be visualized on ultrasound with the transducer placed at the radial side of the pronated wrist with mild ulnar deviation in the longitudinal plane. The long axis of the ligament is displayed as an echogenic,  fibrillar structure attaching the distal radius to the scaphoid  ^2-4.

MRI

The radial collateral ligament is seen on MRI as a linear low signal intensity structure extending from radial styloid to the radial surface of the scaphoid bone. It can be best appreciated on coronal 3D images or MR arthrogram ⁴.

Related pathology

The ligament is involved in the following pathologic conditions ⁶:

• nondissociative carpal instability (CIND)
  • ulnar translocation (type 1): rheumatoid arthritis, Madelung deformity

See also

• wrist ligaments