Biologic augmentation of foot and ankle arthrodeses with an allogeneic cancellous sponge

This case series was conducted to assess the safety and efficacy of using an allogeneic cancellous bone sponge for augmentation of foot and ankle arthrodeses. Twenty-five patients were prospectively enrolled in the study prior to undergoing fusion and were then followed for 12 months postoperatively. There were 45 joints: 7 ankles, 12 subtalars, 12 talonaviculars, 6 calcaneocuboids, 1 naviculocuneiform, 6 first tarsometatarsals, and 1 second tarsometatarsal. Patient-reported outcomes of pain (visual analog scale) and function (American Orthopaedic Foot and Ankle Society score) were obtained preoperatively and postoperatively at 6 and 12 months. No complications were noted intraoperatively or during the follow-up period. Three months postoperatively, radiographic osseous union was noted in 52% (13/25) of patients, which further increased to 96% (24/25) of patients at 6 and 12 months. There was no statistically significant difference in union time between joints [H(6)=11.5; P=.08]. Statistically significant improvements in pain (P≤.002) and function (P<.001) were observed across assessments. This study demonstrated that the cancellous bone sponge appears to be a safe and efficacious product. Randomized controlled trials are warranted to determine if the allogeneic cancellous sponge improves fusion rate, pain, and function.