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Three Part Question

In [patients with a clinically suspected scaphoid fracture in whom wrist splint immobilisation is used] are [wrist splints with thumb extension versus standard wrist splints] better {at reducing complications from occult fractures]

Clinical Scenario

A 23 year old man presents with a painful wrist following a fall on outstretched hand. On examination he has diffuse wrist pain and is tender in the anatomical snuffbox. His wrist and scaphoid views do not demonstrate a fracture. You organise a two week follow up appointment in the ED clinic and give advice regarding analgesia. You have decided to immobilise the wrist in a splint, but wonder if one with a thumb extension is better than a standard splint at immobilising suspected scaphoid fractures.

Search Strategy

Medline 1966- week 4 September 2011 using the OVID interface.

({exp scaphoid bone OR exp carpal bone OR exp wrist injuries OR exp fractures,bone} AND {splint.mp. OR Splints/ OR immobilis$ OR futuro} AND {(thumb adj5 exten$).af. OR thumb.mp. or Thumb/})

Search Outcome

63 papers were found, of which 2 were related to the clinical question.

Relevant Paper(s)

Author, date and country	Patient group	Study type (level of evidence)	Outcomes	Key results	Study Weaknesses
Clay, N R. Diaz, J J. Costigan, P S. Gregg, P J. Barton N J. 1991 September England, United Kingdom	392 patients with confirmed scaphoid fractures	A prospective trial which randomised patients with confirmed scaphoid fractures to either a colles' cast (no thumb immobilisation) or scaphoid cast (thumb immobilisation)	The incidence of non-union was independent of the cast used		All patients were initially placed in a dorsal backslab until being seen at fracture clinic. 100 of 392 patients (25.5%) were excluded from the results as they did not attend their final 6 month review.
			Scaphoid cast non-union (10%)	Colles' cast non-union (10%)
Yanni D, Lieppins P, Laurence M July 1991 United Kingdom	4 patients with non-union of the waist of the scaphoid and 8 cadaveric wrists.	To study the effect of different wrist positions on fracture displacement. This was assessed radiologically with pin markers in both halves of the scaphoid.	Providing there was no ulnar deviation, position of the thumb had no effect on fracture displacement.		A small population was used. A direct comparison was made between a simulated cadaveric scaphoid fracture and those of patients who had a fibrous non-union fracture of the scaphoid.

Comment(s)

The first paper compared the use of colles’ and scaphoid casts in the treatment of scaphoid fractures and showed that fracture healing seems to occur equally well in both. As a scaphoid cast involves thumb immobilisation as far as the interphalangeal joint and a colles' cast does not, it could be inferred that a wrist splint with thumb extension would give no benefit to fracture healing, over a standard wrist splint. The second paper seems to support this finding as it looked at a small group of both patients and cadaveric wrists with scaphoid fractures and found that thumb position had no effect on fracture displacement, as long as the wrist was not in ulnar deviation.

Clinical Bottom Line

While there is no direct evidence to answer the clinical question, the research available strongly suggests that it is reasonable to continue using standard wrist splints to immobilise patients with suspected scaphoid fractures.

References

1. Clay, N R. Diaz, J J. Costigan, P S. Gregg, P J. Barton N J. Need the thumb be immobilised in scaphoid fractures? A randomised prospective trial Journal of Bone and Joint Surgery 1991 Sept; 73(5):828-32
2. Yanni D, Lieppins P, Laurence M Fractures of the carpal scaphoid. A critical study of the standard splint. The Journal of Bone and Joint Surgery 1991 July; 73(4):600-2.