Abstract: Ten heterogenous trials involving 874 adults with generally unstable fractures were grouped into six comparisons. No trial had proven allocation concealment. Four trials (239 participants) found implantation of bone scaffolding (autogenous bone graft (one trial); Norian SRS - a bone substitute (two trials); methylmethacrylate cement (one trial)) improved anatomical outcomes compared with plaster cast alone; and two found it improved function. Reported complications of bone scaffolding were transient discomfort resulting from extraosseous deposits of Norian SRS; with surgical removal of one intra-articular deposit. One trial (323 participants) comparing bone substitute (Norian SRS) versus plaster cast or external fixation found no difference in functional or anatomical outcomes at one year. Statistically significant complications in the respective groups were extraosseous Norian SRS deposits and pin track infection.   One trial (48 participants with external fixation) found that autogenous bone graft did not significantly change outcome. There was one serious donor-site complication. One trial (21 participants) found some indication of worse outcomes for hydroxyapatite bone cement compared with Kapandji's intrafocal pinning. Three trials (180 participants) found bone scaffolding (autogenous bone graft (one trial); Norian SRS (one trial); methylmethacrylate cement (one trial)) gave no significant difference in functional outcomes but some indication of better anatomical outcomes compared with external fixation. Most reported complications were associated with external fixation; extraosseous deposits of Norian SRS occurred in one trial. One trial (93 participants with dorsal plate fixation) found autografts slightly improved wrist function compared with allogenic bone material but with an excess of donor site complications. Bone scaffolding may improve anatomical outcome compared with plaster cast alone but there is insufficient evidence to conclude on functional outcome and safety; or for other comparisons.

Plain-language summary: Ten very different trials involving 874 adults with generally unstable fractures were grouped into six comparisons. No trial used a best-practice method for preventing selection bias. Four trials (239 participants) found implantation of bone scaffolding (autogenous - from the patient - bone graft (one trial); Norian SRS - a bone substitute (two trials); methylmethacrylate cement (one trial)) improved anatomical outcomes compared with plaster cast alone; and two found it improved function. Reported complications of bone scaffolding were transient discomfort resulting from deposits of Norian SRS outside the bone. One deposit required surgical removal. One trial (323 participants) comparing Norian SRS versus plaster cast or external fixation found no difference in functional or anatomical outcomes at one year. External deposits of bone cement and pin track infection were the only significant differences between the two groups. One trial (48 participants) found that autogenous (from the patient) bone graft in the context of external fixation did not significantly change outcome. There was one serious donor-site complication. One trial (21 participants) found some indication of worse outcomes with bone cement compared with percutaneous (through the skin) pinning. Three trials (180 participants) found bone scaffolding (autogenous bone graft (one trial); Norian SRS (one trial); methylmethacrylate cement (one trial)) gave no significant difference in functional outcomes but some indication of better anatomical outcomes compared with external fixation. Most reported complications were associated with external fixation; deposits of Norian SRS outside the bone occurred in one trial. One trial (93 participants treated with plate fixation) comparing allogenic bone material (from other people) versus autogenic bone-graft found slightly improved wrist function for the autograft group but an excess of complications relating to graft harvesting. The review concluded that while bone scaffolding may improve anatomical outcome compared with plaster cast immobilisation alone, there is insufficient evidence to conclude on function and safety; or on outcome for other comparisons.