Complications With the Use of BMP-2 in Scaphoid Nonunion Surgery

Abstract

Purpose: In an effort to improve fracture healing and decrease the need for autologous bone graft, products such as recombinant human bone morphogenetic protein (rhBMP-2) have been developed and used in both spine and nonspine surgery. There is a paucity of literature regarding the use of rhBMP-2 in scaphoid nonunion surgery with very little reporting on the complications associated with its use. The objective of this study was to retrospectively review the complications documented for a case series of patients treated with revision fixation, bone graft, and rhBMP-2 in revision scaphoid nonunion surgery.

Methods: We retrospectively reviewed 6 cases of scaphoid nonunion revision surgery comprising open reduction and internal fixation (ORIF). All cases were performed for persistent nonunion after a previous scaphoid ORIF. All patients were treated with revision screw fixation, bone graft, and rhBMP-2. Union was determined by computed tomography in all cases. Complications of nonunion, heterotopic bone formation, delayed wound healing, functional loss of motion, and need for revision surgery are reported.

Results: Between 2011 and 2014, 6 cases in which rhBMP-2 was used in revision scaphoid nonunion surgery were identified. All patients had failed an initial attempt at ORIF after delayed union or nonunion. The time from injury to index ORIF ranged from 3 months to 4 years (mean, 24 months). Revision surgery with rhBMP-2 was performed at an average of 6 months from the index ORIF. Of the 6 cases, 2 had resultant persistent nonunion. Both underwent scaphoid excision and midcarpal arthrodesis. Four cases developed notable heterotopic ossification (one of which required revision surgery). One patient had a loss of functional motion after the revision surgery. There were no cases of delayed wound healing. Only one of the 6 patients healed without complications.

Conclusions: In this case series, the use of rhBMP-2 in scaphoid nonunions was associated with a higher complication rate than reported in previous studies. Surgeons performing off-label use of rhBMP-2 should be aware of the potential for complications including heterotopic ossification.

Type of study/level of evidence: Therapeutic IV.

Keywords: BMP-2; Recombinant human bone morphogenetic protein; scaphoid nonunion surgery; surgical complications.