How "successful" is calvarial reconstruction using frozen autologous bone?

BACKGROUND: The authors investigated the long-term outcome of frozen autologous bone cranioplasty in patients who had undergone decompressive craniectomy for severe traumatic brain injury.

METHODS: A retrospective analysis was undertaken of all patients who had undergone decompressive craniectomy at the two major trauma hospitals in Western Australia between 2004 and 2010. A specific note was made regarding "failure" of frozen autologous bone because of either infection or bone flap resorption.

RESULTS: A total of 194 patients required either unilateral or bilateral decompressive craniectomy for severe traumatic brain injury during the study period. Of these patients, 156 had had an autologous cranioplasty. Among these patients, the cranioplasty was judged a failure in 45 (29 percent). Thirteen (8.5 percent; 95 percent confidence interval, 5.0 to 14.0 percent) developed an infection requiring removal of the cranioplasty. Thirty-two (21 percent; 95 percent confidence interval, 15 to 28 percent) developed clinical symptoms or signs relating to resorption of the cranioplasty. Fourteen (9 percent) required secondary titanium cranioplasty, two were offered surgical augmentation but declined, and 16 (10 percent) developed significant bone resorption through both the inner and outer tables of the skull.

CONCLUSIONS: This study has demonstrated that the use of frozen autologous bone is associated with a high long-term failure rate; however, this does not necessarily imply that alternative materials should be routinely used. Although a number are available, their efficacy over and above frozen autologous bone remains to be established and perhaps this will only be demonstrated in the setting of a formal clinical trial.

CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.