Patient Preparation and Positioning

The procedure is performed under regional anesthesia with the arm secured to an arm board and upward traction of 5 to 7 kg applied to the hand, wrist, and forearm.

Arthroscopic Portals and Exploration

Three portals are generally used during this procedure ( Fig. 20.1 ):

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  Standard 3–4 portal, extended to ~1 cm to allow the implant to pass through it

  
  
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  4–5 or 6R portals for the scope

  
  
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  Radial midcarpal (MCR) portal for midcarpal verification

The procedure starts with the 3–4 and 4–5 or 6R portals.

The scope is inserted into the medial portal. A shaver is used to debride the joint (synovitis, bone, and/or cartilage debris). The proximal pole is located and the degree of necrosis measured (one or multiple fragments, etc.). The arthroscope and sheath are then introduced through the MCU portal to assess the proximal pole’s position relative to the remainder of the scaphoid and to the lunate ( Fig. 20.2a, b ).

Proximal Pole Excision

All of the proximal pole’s fragments will be taken out through the 3–4 portal with the scope in the radiocarpal ulnar portal. But first, the scapholunate interosseous ligament must be cut if it is still intact. A small no. 11 scalpel is used ( Fig. 20.3a, b ). Stevens tenotomy scissors are then used to cut through the entire scapholunate ligament ( Fig. 20.4a, b ). The proximal pole or its various fragments are then removed using hemostats ( Fig. 20.5a–c ).

If the dorsal and volar portions of the scapholunate ligament are difficult to cut, this can be accomplished with a shaver inserted in the 3–4 portal; the scope is placed into the radiocarpal ulnar portal for the dorsal portion and the MCU portal for the volar portion.

If the scaphoid’s proximal end is convex, a bur is inserted through the 3–4 portal and used to reshape this end until it becomes concave and can match the implant’s shape ( Fig. 20.6a, b ).