Surgical fixation compared with cast immobilisation for adults with a bicortical fracture of the scaphoid waist: the SWIFFT RCT.

BACKGROUND

Scaphoid fractures account for 90% of carpal fractures and occur predominantly in young men. Immediate surgical fixation of this fracture has increased.

OBJECTIVE

To compare the clinical effectiveness and cost-effectiveness of surgical fixation with cast treatment and early fixation in adults with scaphoid waist fractures that fail to unite.

DESIGN

Multicentre, pragmatic, open-label, parallel two-arm randomised controlled trial with an economic evaluation and a nested qualitative study.

SETTING

Orthopaedic departments of 31 hospitals in England and Wales recruited from July 2013, with final follow-up in September 2017.

PARTICIPANTS

Adults (aged ≥ 16 years) presenting within 2 weeks of injury with a clear, bicortical fracture of the scaphoid waist on plain radiographs.

INTERVENTIONS

Early surgical fixation using Conformité Européenne-marked headless compression screws. Below-elbow cast immobilisation for 6-10 weeks and urgent fixation of confirmed non-union.

MAIN OUTCOME MEASURES

The primary outcome and end point was the Patient-Rated Wrist Evaluation total score at 52 weeks, with a clinically relevant difference of 6 points. Secondary outcomes included Patient-Rated Wrist Evaluation pain and function subscales, Short Form questionnaire 12-items, bone union, range of movement, grip strength, complications and return to work.

RESULTS

The mean age of 439 participants was 33 years; 363 participants were male (83%) and 269 participants had an undisplaced fracture (61%). The primary analysis was on 408 participants with valid Patient-Rated Wrist Evaluation outcome data for at least one post-randomisation time point (surgery,

LIMITATION

There were 17 participants who had initial cast treatment and surgery for confirmed non-union, which in 14 cases was within 6 months from randomisation and in three cases was after 6 months. Three of the four participants in the cast group who had a non-union at 52 weeks were not offered surgery.

CONCLUSIONS

Adult patients with an undisplaced or minimally displaced scaphoid waist fracture should have cast immobilisation and suspected non-unions immediately confirmed and urgently fixed. Patients should be followed up at 5 years to investigate the effect of partial union, degenerative arthritis, malunion and screw problems on their quality of life.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN67901257.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in

Fracture of the scaphoid bone (one of eight small bones in the wrist) is common in young active people. It is caused by a fall on the hand or the hand being suddenly forced backwards. The usual treatment is to rest the wrist in a plaster cast for 6–10 weeks and allow the broken bone to heal. In 1 in 10 cases in which the fracture is treated in a plaster cast, the bone does not heal and an operation is needed. In the operation, the broken bone is held still with a screw. In the last few years, it has become more common to fix the broken bone with a screw in the first few days after injury, instead of resting the wrist in a plaster cast. It is not clear if fixing the bone early with a screw, compared with resting the wrist in a cast, gives better outcomes for patients and if one treatment is better value for money for the NHS. In this study, 439 adult patients agreed either to have surgery to hold the broken scaphoid with a special screw or to have the wrist held still in a plaster cast (with surgery offered after 6 weeks to those who were still not healed). The decision about which treatment to use was made using randomisation, which is similar to tossing a coin. Patients reported their own wrist pain and function at 6, 12, 26 and 52 weeks. Information was also collected on general health, bone healing, grip strength and range of movement, complications from treatment and costs. No important differences were found in patients’ wrist pain and function at 52 weeks. The bone did not heal properly in four patients in the surgery group or in nine patients in the plaster cast group at 52 weeks. For one of these patients in the surgery group and four of these patients in the plaster cast group, the bone did not join at all. Eight patients in the surgery group had further surgery following their initial operation to fix their wrist, and one patient in the cast group required repeated surgery because the bone did not join at all. The overall cost of treating with a plaster cast was lower than that of early surgery. Therefore, the findings of the study suggest that a plaster cast should be used initially and that the bone should be immediately fixed with a screw if it does not heal.