Age / Sex : 52 / M

Chief complaint: wrist pain

1) What is your impression?

Two weeks later, you can see the final diagnosis with a brief discussion of this case.

(답안은 한 개만 보내주시기 바랍니다)

Courtesy: 윤영철 (Young Cheol Yoon), 서울삼성병원 (Samsung Medical Center)

Scaphoid non union advanced collapse (SNAC), Stage II

Discussion

A scaphoid non union advanced collapse (or SNAC wrist) is complication that can occur with a scaphoid fracture. In a SNAC wrist, the proximal scaphoid fragment usually remains attached to the lunate (which rotate together during extension), while the distal scaphoid fragment rotates into flexion. This results in abnormal contact in the radioscaphoid compartment, characterized by early styloid osteoarthritis between the distal scaphoid fragment and the radial styloid process.

Staging:

stage 1: osteoarthritis between the distal scaphoid fragment and the radial styloid process

stage 2: same as stage 1 with the addition of osteoarthritis between the scaphoid and the capitate.

stage 3: osteoarthritis affecting the radial styloid, distal scaphoid, and scaphocapitate with progression to the lunocapitate

References

1. Vender MI, Watson HK, Wiener BD, Black DM. Degenerative change in symptomatic scaphoid nonunion. J Hand Surg [Am] 1987; 12-A:514-9.1.

2. Tomaino MM, Miller RJ, Cole I et-al. Scapholunate advanced collapse wrist: proximal row carpectomy or limited wrist arthrodesis with scaphoid excision?. J Hand Surg Am. 1994;19 (1): 134-42. doi:10.1016/0363-5023(94)90237-2 - Pubmed citation