Purpose: Scaphoid non-union rates can be as high as 2-5%, of which smoking may play a big part. This systematic review aimed to identify the extent the effect of smoking has on union rates in patients who suffer from acute fractures or non-unions of the scaphoid.
Methods: Using PRISMA guidelines, two databases were searched for original articles comparing smoking to non-union rates for the management of scaphoid fractures and non-unions. Data was then analysed to identify relative risk of smoking after treatment. Inclusion criteria involved comparison between smokers and non smokers, extractable data, patients > 16 years and clear definitions on what is classed as a non-union.
Results: A total of 3252 results were narrowed down to 18 studies. Four studies, involving 30,320 patients, had acute fractures, and fourteen studies reviewed 1194 patients with non-unions. Of the acute fracture patients, 97.4% of non-smokers achieved union compared with 95.6% of smokers. Pooling the data led to a relative risk for non-union of 1.68 (1.46-1.93). Of the non-union patients, 79.0% of patients who did not smoke achieved union after treatment, compared with 57.4% of smokers. Relative risk for smoking for further non-union in this group was 2.03 (1.70-2.43). When subdividing this group into patients who received vascularised and non-vascularised bone graft, the relative risk of non-union from smoking was 3.09 (1.92-4.97) and 5.14 (2.35-11.24) respectively.
Conclusion: This is the first paper of its kind to give specific figures for the harmful effects smoking has on scaphoid management, however it is limited by lack of consistency in treatment, heterogenicity and a lack of data. Given the extent of its impact, smoking cessation pathways should be developed as part of the concurrent management of scaphoid injuries or non-union.
Keywords: Fracture; Non-union; Scaphoid; Smoking; Union.
© 2025. The Author(s), under exclusive licence to Springer-Verlag France SAS, part of Springer Nature.