The use of freeze-dried allograft bone for anterior cervical fusions

A consecutive series of 87 patients undergoing Smith-Robinson anterior cervical fusion were analyzed. Either freeze-dried tricortical iliac crest bone or tricortical autograft bone was used. Surgical technique was otherwise identical. Radiography showed delayed union at 3 months in 13% of patients with autograft and in 37% of patients with freeze-dried allograft. At 1 year, radiography showed nonunion in 8% of patients with autograft and in 22% of patients with allograft. One-level procedures had a delayed union rate of 7% for autograft and 21% for allograft. Nonunion in one-level procedures was 5% for both autograft and allograft. For two-level procedures, the nonunion rate was 17% for autograft and 63% for allograft. Graft collapse was more commonly seen with freeze-dried allograft (30%) than with autograft (5%). Relief of neck and arm pain, however, was similar in both groups.