Seven studies (n=692) were included. Four studies (n=228) compared operative versus non-operative treatment and three (n=464) compared different types of casting.
All of the included studies had methodological flaws. Five studies reported the randomisation method and two used quasi-randomised methods. In none of the studies was the outcome assessor blinded. Five studies reported drop-outs or losses to follow-up, but only one used intention-to-treat analysis. Two studies were classified as high quality.
Nonunion was significantly less common in patients undergoing operative compared with non-operative treatment (RR 0.26, 95% CI: 0.07, 0.91, p=0.04; based on 4 studies; I-squared 47.8%). The results were not robust to sensitivity analysis. Reanalysis using a random-effects model and analyses assuming best- and worst-case scenarios for missing data showed no significant difference between treatments. When limiting the analysis to the two high-quality studies, the RR approached statistical significance in favour of operative treatment (RR 0.06, 95% CI: 0, 0.94, p=0.05).
Return to work was significantly faster in patients undergoing operative compared with non-operative treatment (WMD -5.47 weeks, 95% CI: -9.97, -0.98, p=0.02; based on 3 studies) but significant heterogeneity was found (I-squared 92.7%). Substantial heterogeneity remained when the analysis was limited to the two high-quality studies (I-squared 96.2%).
Complications were significantly more common in patients undergoing operative treatment than non-operative treatment (RR 12.23, 95% CI: 2.32, 64.60, p=0.0003; based on 4 studies); no significant heterogeneity was found (I-squared 0%). The results were robust to best- and worst-case scenarios for missing data and analysis using only data from the high-quality studies.
In one study with 12-year follow-up, there was a non-statistically significant increase in the risk of osteoarthritis of the scaphotrapezial joint in patents undergoing operative compared with non-operative treatment (RR 2.43, 95% CI: 0.98, 6.03), but no significant difference between treatments in symptomatic osteoarthritis. There was no significant difference between treatments in radiocarpal osteoarthritis or symptomatic radiocarpal osteoarthritis.
There were no consistent significant differences in operative and non-operative groups across all time periods reported for grip strength (4 studies) or ROM of the wrist (4 studies), and no significant differences between treatments in patient satisfaction (2 studies).
The three studies that compared different types of cast found no differences in rates of nonunion between treatments.