The lunotriquetral interosseous ligament stabilises the LT joint and prevents VISI deformity. Unlike the SLIL where the dorsal component is strongest, the LT ligament's volar component is the most important. LT instability is less common than SL instability but produces ulnar wrist pain and a positive LT shear test (the Kleinman shear test). VISI collapse — the lunate palmarflexion deformity from LT instability — is the ulnar-side analogue of DISI.
| Origin | Lunate proximal articular margin (ulnar side) |
|---|---|
| Insertion | Triquetrum proximal articular margin |
| Actions | Maintains lunotriquetral articulation; prevents VISI (volar intercalated segment instability) collapse; the ulnar counterpart of the SLIL |
|---|
LT ligament tears produce the Kleinman ballottement test (LT shear) pain and clunk. Arthroscopic LT ligament debridement for partial tears and LT fusion or ligamentoplasty for complete tears provide definitive management. LT fusion sacrifice some midcarpal motion but reliably relieves LT instability pain.
Lunotriquetral ligament tear producing VISI collapse and ulnar wrist pain managed with arthroscopic debridement or LT fusion.
