Cranioplasty after decompressive hemicraniectomy: underestimated surgery-associated complications?

OBJECTIVE: Decompressive hemicraniectomy (DC) and duroplasty after malignant brain infarction or traumatic brain injury is a common surgical procedure. Usually, preserved bone flaps are being reimplanted after resolution of brain swelling. Alloplast cranioplasties are seldom directly implanted due to the risk of wound healing disorders. While numerous studies deal with DC, little is known about the encountered problems of bone flap reimplantation. Thus, aim of the study was to identify surgery-associated complications after bone flap reimplantation.
METHODS: We performed a retrospective chart analysis of patients that underwent DC and subsequent bone flap reimplantation between 2001 and 2011 at our institution. We registered demographic data, initial clinical diagnosis and surgery-associated complications.
RESULTS: We identified 136 patients that underwent DC and subsequent reimplantation. Forty-one patients (30.1%) had early or late surgery-associated complications after bone flap reimplantation. Most often, bone flap resorption and postoperative wound infections were the underlying causes (73%, n=30/41). Multivariate analysis identified age (p=0.045; OR=16.30), GOS prior to cranioplasty (p=0.03; OR=2.38) and nicotine abuse as a prognostic factor for surgery-associated complications (p=0.043; OR=4.02). Furthermore, patients with early cranioplasty had a better functional outcome than patients with late cranioplasty (p<0.05).
CONCLUSIONS: Almost one-third of the patients that are operated on for bone flap reimplantation after DC suffer from surgery-associated complications. Most often, wound healing disorders as well as bone flap resorption lead to a second or even third operation with the need for artificial bone implantation. These results might raise the question, if subsequent operations can be avoided, if an artificial bone is initially chosen for cranioplasty.