‣What are the ligaments of the wrist? Significance?"There are Dorsal and Volar ligaments; Extrinsic (from outside carpus) and intrinsic ligaments"‣Volar [Space of Porier between RSC and LRL)Extrinsic = Radioscaphocapitate (RSC), Long Radiolunate (LRL), Short Radiolunate (SRL) + 3 ulnar ligaments (UC, UL, UT)Intrinsic = Scapholunate, Lunotriquetrium‣Dorsal (Buerger's Flap - borders of DRC, DIC ligament)Note the apex is at the TriquetriumExtrinsic = Dorsal Radio Carpal (DRC) aka Dorsal Radio Luno TriquetrialIntrinsic = Dorsal intercarpal ligament (DIC)‣What is the space of porier?Area of weakness between Radioscphocapitate and Long Radiolunate‣What is the role of the lunate?Lunate acts as “intercalated torque converter” between the scaphoid that flexes and the triquetrum that extendsAttached to either bone by SL and LT intrinsic volar ligamentsAny disruption causes the lunate to follow the intact ligamentIf SL injured, lunate follows triquetrium and extends dorsally = DISIIf LT injured, lunate follows scaphoid to flex volarly = VISI‣Types of carpal instability?Mayo ClassificationCI-Dissociative (CID) = within same row – e.g SL (DISI), LT (VISI) injuryCI – Non Dissociative (CIND) = between rows e.g. Radiocarpal dislocationCI- Complex (CIC) = between and within rows e.g. PerilunateCI-Adaptive (CIA) – from outside carpus = Radius malunion‣What are the Gilula lines?3 lines‣What is the spilled tea-cup sign/ Piece of pie sign?Both signs are Specific for lunate dislocation, mayfield 4Piece of Pie on APSpilled Tea cup on lateralHelps to differentiate perilunate vs lunate dislocation.Perilunate Dislocation ‣What are the types?Mayfield StagesMayfield 1 = SL ligament only torn2 = + RSC Ligament torn (disrupting LC joint)3 = + LT ligament torn 4 = + DRC ligament failure‣Perilunate Dislocation (Mayfield 3) = lunate stays in position but carpus out (4 types) - still held by DRC ligament)[Lesser Arc] Perilunate = pure ligamentous Mayfield 3[Greater Arc - 3 kinds] Transcaphoid PerilunateTransradial styloidTrans-scaphoid, transcapitate perilunar‣Lunate Dislocation = Carpus aligned but lunate out from space of Porier = Mayfield 4‣Which ligament is not torn in perilunate/ lunate dislocation?Short Radiolunate ligament!‣How to reduce?Closed reduction with Tavernier maneuver under Bier's Block (sedation is not enough)Chinese Finger traps, elbow 90 deg, Hand traction 5-10 lbs for 10 min [golgi tendon reflex]Hyperextened wrist, thumb at lunate (to keep lunte dorsiflexed to allow capitate to clear dorsal rim of lunate)Flex wrist with traction maintainedSlab, elevate in Bradford SlingI will try once and if it fails, will do it under GA to avoid further traumatizing of the soft tissue and worsening of median nerve injury‣If fail closed reduction?Open reductionVolar Approach will be used to decompress median nerve or propylaxtic CT releaseClose ➔ back slab ➔ CT scan, monitor for CTS‣What if there is median nerve involvement?Need urgent release“I will do an extended CT approach going proximal to the wrist crease, crossing in the ulnar direction to avoid the palmar cutaneous nerve”Need to avoid the palmar cutaneous nerve 5cm proximal to the wrist‣What will you do at 10pm if unable to reduce but no NV?This injury may require open reduction requiring a dorsal incision. As I do not want to jeopardize the hand surgeons planes, I will:Strict elevation on bradford sling till next dayWith very close monitoring for median nerve symptoms‣What will you do at 10pm if unable to reduce but has median nerve symptoms?I will do a volar open carpal tunnel release and attempt reduction through thisIf this is not possible, I will just leave the wound open, dress and bandageAllow primary hand surgeon to reduce and repair SL ligaments using dorsal approach‣What are your approaches for definitive management?Unstable fracture and Closed reduction poor outcomes with high risk of recurrence"Goal is to address soft tissue injuries and bony injuries"Approach - Always need a dorsal approach. Add volar approach if cannot reduce OR need to release CTS OR choose to fix LT ligamentVolar – to assess CTS, reduce lunate, repair volar capsuleDorsal - what flap?Incision Between 3 and 4 CompartmentsIf need to extend, can do Buerger’s flap centered on triquetriumV-shaped flap created along edge of dorsal intercarpal ligament and dorsal radiocarpal ligaments. (only these 2 main ligaments on dorsum)‣What are your goals of management?Goal: repair dorsal SL ligament, fix fractures if present, pinning of bonesSL ligament - "Suture anchor" - this is universally accepted; fix via dorsalLT ligament - Suture anchor is optional here. Experience says wires is enough; fix via volarFix other fractures with screwsJin Xi says generally 3 wires - SL, LT, SC‣What bones to pin?THink about the ligaments disrupted - SL, LT and RSC. So pin the SL, LT and SC‣What are the general expected outcomes for Perilunate/ Lunate dislocation?Patient will have some weakness and stiffness, usually have 80% of grip strength and ROM (Lim Jin Xi)‣Chronic management of pain?4CF or PRC