synonyms:4 corner fusion, wrist arthrodesis, carpal fusion, carpal arthrodesis
4 Corner Fusion CPT
4 Corner Fusion Indications
4 Corner Fusion Contraindications
4 Corner Fusion Alternatives
4 Corner Fusion Pre-op Planning
- Ensure appropriate fixation is available. Acumed Hub Cap Limited Wrist Fusion Plate or similar plate. Alternatives: headless compression screws, k-wires (require later removal)
4 Corner Fusion Technique
- Pre-op antibiotics
- Sign operative site
- Supine position with hand table
- Regional / general anesthesia
- Prep and drap in standard sterile fashion
- Midline, dorsal, longitudinal incision
- Dissection under 2.5x loop magnification
- Extensor retinaculum incisied (longitudunal or Z-incision)
- 4th externsor compartment tendons retracted
- 3rd extensor compartment open and tendon retracted
- Dorsal capsule incised longitudinally, exposing carpal bones
- Excise Scaphoid preserving extrinsic ligaments
- Using curretes and osteotomes or bur remove cartilage between the capitate, hamate, lunate and triquetrum.
- Anatomically reduce lunate to the capitate
- Provisionally fix the carpal bones with k-wires as volar as possible. Suggested order for K-wires: 1) Hamate to Capitate,
2) Triquetrum to Lunate, 3) Triquetrum to Capitate.
- Center the reamer over the junction of the four carpals. Ream until the dorsal surface of the carpals lies between the two lines on the reamer head so the plate will be recessed.
- Obtain distal radius bone graft. Back fill the bone graft site with remnants of the scaphoid with any cartilage removed.
- Place the Hub-cap plate in its recessed position with single screw hole aligned with the hamate.
- Drill the hamate, measure depth, place screw. Holes should be drilled to within 2mm of the far cortex. Avoid bicortical drilling.
- Repeat for remain screw holes. Recommended screw insertion order is: 1) Hamate, 2) Lunate, 3) Capitate, 4) Triquetrum. Generally two screws in each carpal bone except the hamate.
- Varify plate and screw placement with fluoroscopy
- Close capsule
- Close extensor retinaculum
- Close skin
- Volar splint
4 Corner Fusion Complications
4 Corner Fusion Follow-up care
- Post-op: volar splint
- 7-10 Days:wound check, place in removable short arm splint. Xrays. Encourage hand/digital ROM exercises
- 3 Weeks:
- 6 Weeks:
- 2 Months:
- 3 Months:
- 6 Months:
4 Corner Fusion Outcomes
- Range of motion averages 45% of the uninjured side (average extension, 35°; average flexion, 26°). Grip strength 82% of uninjured side. Pain 2.3/10. (Merrell GA, J Hand Surg 2008;33:635)
4 Corner Fusion Review References