Difference in Carpal Alignment between Scapholunate Dissociation and Kienbock Disease: A Retrospective Study

Area of Science:

• Orthopedics
• Hand Surgery
• Wrist Biomechanics

Background:

• Scapholunate dissociation is a common wrist instability leading to osteoarthritis.
• Kienbock disease also causes wrist osteoarthritis, involving carpal instability.
• Distinct mechanisms may underlie these conditions.

Purpose of the Study:

• To compare carpal alignment in scapholunate dissociation versus Kienbock disease.
• To investigate the role of secondary stabilizers in maintaining carpal alignment after ligamentous injury.

Main Methods:

• Retrospective review of 17 patients with scapholunate dissociation (Geissler grade 4) and 14 with Kienbock disease.
• Kienbock disease treated with lunate resection and vascularized pisiform transfer.
• Pre- and postoperative radiographic evaluation of carpal alignments.

Main Results:

• Scapholunate dissociation showed increased lunate dorsiflexion and dorsal positioning of scaphoid/capitate.
• Preoperative dorsal subluxation of the scaphoid was observed in 11/17 scapholunate dissociation cases.
• No carpal collapse progression was noted postoperatively in either group.

Conclusions:

• Sacrifice of the scapholunate/lunotriquetral interosseous ligament does not necessarily lead to static scapholunate dissociation.
• Secondary wrist stabilizers appear capable of preserving carpal alignment.