Osteotomy for sigmoid notch obliquity and ulnar positive variance

Area of Science:

• Orthopedic surgery
• Hand and wrist surgery
• Radiology

Background:

• Ulnar wrist pain can stem from various causes, including ulnar carpal abutment due to a distally facing sigmoid notch (reverse obliquity).
• This specific abnormality poses treatment challenges, as simple ulnar shortening can lead to distal radioulnar joint (DRUJ) incongruity.

Observation:

• A 23-year-old woman experienced ulnar wrist pain, particularly with forearm rotation, following a distal radius fracture treated conservatively 10 years prior.
• Examination revealed DRUJ tenderness and reduced wrist function. Radiographs showed ulnar positive variance, ulnar styloid nonunion, and significant sigmoid notch reverse obliquity.

Findings:

• The patient underwent a rotation sigmoid notch osteotomy combined with ulnar shortening to correct the sigmoid notch's orientation and improve DRUJ congruity.
• This surgical approach successfully realigned the sigmoid notch with the ulnar head, addressing the underlying cause of ulnar carpal abutment.

Implications:

• This case highlights a coronal plane osteotomy of the sigmoid notch as an effective treatment for reverse obliquity, particularly in young patients where traditional salvage options are less suitable.
• The described rotation osteotomy provides a specific solution for sigmoid notch incongruity, potentially preventing the need for more extensive salvage procedures and preserving wrist function.