RhBMP7 use for treating scaphoid non-union: 5 cases assessed at 10 years' follow-up

The scaphoid is the most common non-union site in the wrist. Fixation with vascularised or non-vascularised autograft is the gold standard when it comes to treating these non-unions. But, what can we offer if the autograft fails? Using osteoinductive proteins in difficult cases of long bone non-union yields good results. However, only a few studies have been published on their use for scaphoid non-union. In our study, five patients with an average age of 32 years (ranging from 21 to 44 years) with old non-union (more than 24 months) of the scaphoid were treated after autograft treatment had failed. The procedure consisted of reaming the non-union site, then adding bone autograft combined with BMP-7 (Osigraft®) in the defect and fixing it all with a screw or K-wire. Postoperative immobilisation was prescribed. Only one patient achieved bone union (20%) despite an average follow-up of 10 years (80-143 months). The average flexion-extension loss was 16.6° (0-30) relative to the contralateral side. The average strength deficit was 450 grams (0-2000) for pinch and 12.1kg (0-29) for grip compared to the contralateral side. Self-assessment questionnaires had an average PRWE at 28.9 (10.5-49) and an average QuickDASH at 28.6 (9.09-61.36). Our study could not demonstrate any real benefit of using BMP-7 for treating old scaphoid non-union despite an elevated cost. Further research is needed to look at other treatment approaches, for instance, the use of new scaffolds combining VEGF and BMP.