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Volar lunotriquetral ligament

The volar lunotriquetral ligament (VLT ligament) is a key intrinsic ligament of the wrist, connecting the palmar aspects of the lunate and triquetrum. It is one of the major stabilizers of the lunotriquetral (LT) joint, located on the ulnar side of the proximal carpal row.

This ligament plays a critical role in maintaining carpal stability, particularly during ulnar deviation and wrist flexion. It works in concert with the dorsal lunotriquetral ligament and the interosseous LT ligament to maintain synchronous motion between the lunate and triquetrum.

Injury or degeneration of the VLT ligament leads to lunotriquetral instability, pain, and abnormal motion between the proximal carpal bones, often presenting as ulnar-sided wrist pain.

Synonyms

  • Palmar lunotriquetral ligament

  • Volar LT ligament

  • Palmar intercarpal ligament (lunotriquetral portion)

Origin and Insertion

  • Origin: Palmar (volar) surface of the lunate, near its ulnar and distal margin

  • Insertion: Palmar surface of the triquetrum, near its radial margin

  • The ligament fibers run obliquely and slightly distally, forming a strong band bridging the lunotriquetral joint capsule.

Structure and Composition

  • Composed of dense fibrous connective tissue with interspersed collagen bundles arranged obliquely.

  • Often accompanied by adjacent fibrocartilaginous reinforcement.

  • Forms part of the volar carpal capsule, blending with fibers of the palmar intercarpal and ulnocarpal ligaments.

  • Typically thicker and stronger than the dorsal component.

Relations

  • Anteriorly (superficial): Flexor retinaculum, flexor carpi ulnaris tendon, and ulnar neurovascular bundle

  • Posteriorly (deep): Lunotriquetral joint space

  • Medially: Triquetrum and ulnocarpal joint capsule

  • Laterally: Lunate and adjacent radiolunate ligament fibers

  • Inferiorly: Proximal surface of the midcarpal joint capsule

Function

  • Primary stabilizer of the lunotriquetral articulation

  • Prevents excessive volar translation of the triquetrum relative to the lunate

  • Ensures coordinated movement of the proximal carpal row during flexion–extension and ulnar deviation

  • Contributes to load distribution across the ulnar wrist and carpus

  • Works synergistically with dorsal and interosseous LT ligaments to maintain carpal alignment

Clinical Significance

  • Tears and instability: Common cause of ulnar-sided wrist pain; may occur with falls or repetitive wrist loading

  • Dynamic instability: Seen when ligament laxity causes abnormal motion despite intact dorsal components

  • Chronic degeneration: Associated with ulnocarpal impaction and triangular fibrocartilage complex (TFCC) injury

  • Lunotriquetral dissociation: Severe ligament disruption causing abnormal lunate–triquetral gap on imaging (“LT widening”)

  • Arthroscopy: Gold standard for diagnosis; imaging provides noninvasive assessment

  • Surgical importance: Repaired or reconstructed during wrist stabilization procedures

MRI Appearance

  • T1-weighted images:

    • Ligament: low signal (dark), linear band connecting lunate and triquetrum

    • Surrounded by intermediate-signal fat in the volar carpal space

    • Tear: discontinuity or thickening with intermediate-to-bright signal replacing normal low-signal fibers

  • T2-weighted images:

    • Normal ligament: low to intermediate signal, continuous, sharply defined band

    • Partial tear: focal bright hyperintense area within ligament fibers

    • Complete tear: gap or fluid signal traversing between lunate and triquetrum

    • Adjacent bone marrow edema may be present in lunate or triquetrum

  • STIR:

    • Normal ligament: intermediate-to-dark signal

    • Pathologic: bright hyperintense signal in ligament substance or periligamentous region, indicating edema or synovitis

  • Proton Density Fat-Saturated (PD FS):

    • Normal: dark, homogeneous linear structure

    • Partial tear: localized bright signal within ligament substance

    • Complete tear: discontinuity with fluid-filled gap between carpal bones

    • Excellent for depicting small intra-ligamentous tears and pericapsular inflammation

  • T1 Fat-Sat Post-Contrast:

    • Normal ligament: minimal enhancement

    • Inflamed or healing tissue: shows faint peripheral or diffuse enhancement

    • Chronic tears: non-enhancing fibrotic gap with enhancing periligamentous synovium

MR Arthrography Appearance

  • Normal: Contrast confined to the radiocarpal and midcarpal compartments; no contrast leakage through lunotriquetral joint

  • Partial tear: Minimal contrast tracking along ligament fibers or faint leakage into adjacent joint recess

  • Complete tear: Contrast passage between lunate and triquetrum, confirming communication between radiocarpal and midcarpal spaces

  • Most sensitive sequence for occult ligament tears and early instability

CT Appearance

Non-Contrast CT:

  • Ligament not directly visualized due to soft-tissue density

  • Indirect signs: Joint space widening between lunate and triquetrum, subchondral sclerosis, or cystic changes

  • Useful for assessing associated osseous avulsion or carpal malalignment

Post-Contrast CT (standard):

  • Subtle enhancement of surrounding synovium or capsule in inflammation

  • Visualizes adjacent periarticular changes, erosions, or cysts

CT Arthrography Appearance

  • Normal: Contrast remains confined to single compartment; intact ligament prevents intercompartmental communication

  • Partial tear: Small amount of contrast insinuates into ligament fibers or subcapsular recess

  • Complete tear: Contrast freely passes between the lunate and triquetrum, filling both radiocarpal and midcarpal joints

  • Highly sensitive for detecting subtle ligament disruptions and evaluating postoperative integrity

MRI images

Volar lunotriquetral ligament axial cross sectional anatomy 3T MRI AI enhanced radiology image-img-00000-00000

MRI images

Volar lunotriquetral ligament mri coronal image