Three-dimensional printed upper-limb prostheses lack randomised controlled trials: A systematic review.

The review did not state a total participant count across the eight studies. Only eight studies were included, all small non-randomised trials without controls, and five were individual case studies. No study compared the 3D printed device with current products or methods, blinded participants or outcome measurers, or demonstrated external validity. Only one study had sufficient power to detect a clinically important effect. Six studies aimed to assess functionality, but their focus was on describing device design rather than assessing clinical efficacy and effectiveness. Four of the five studies that tested devices with amputees were tested with children. Only one included study used an above-elbow device. No report assessed device strength and durability, and no follow-up longer than 6 months was reported. The review did not have enough data to perform a meta-analysis. The search covered publications up to September 2016, so newer evidence is not included.

The authors declared no potential conflicts of interest and said they received no financial support for the research, authorship, or publication. The article also names Wellcome Trust and General Sir John Monash Foundation as funders.

Do not conclude that 3D printed upper-limb prostheses are proven effective because the studies reported positive results. None were randomised or controlled, none compared the device with conventional prostheses, and only one had sufficient power to detect a clinically important effect.