Cranioplasty after decompressive craniectomy: is there a rationale for an initial artificial bone-substitute implant? A single-center experience after 631 procedures

Abstract

OBJECT The complication rate for cranioplasty after decompressive craniectomy is higher than that after other neurosurgical procedures; aseptic bone resorption is the major long-term problem. Patients frequently need additional operations to remove necrotic bone and replace it with an artificial bone substitute. Initial implantation of a bone substitute may be an option for selected patients who are at risk for bone resorption, but this cohort has not yet been clearly defined. The authors’ goals were to identify risk factors for aseptic bone flap necrosis and define which patients may benefit more from an initial bone-substitute implant than from autograft after craniectomy. METHODS The authors retrospectively analyzed 631 cranioplasty procedures (503 with autograft, 128 with bone substitute) by using a stepwise multivariable logistic regression model and discrimination analysis. RESULTS There was a significantly higher risk for reoperation after placement of autograft than after placement of bone substitute; aseptic bone necrosis (n = 108) was the major problem (OR 2.48 [95% CI1.11–5.51]). Fragmentation of the flap into 2 or more fragments, younger age (OR 0.97 [95% CI 0.95–0.98]; p < 0.001), and shunt-dependent hydrocephalus (OR 1.73 [95% CI1.02–2.92]; p = 0.04) were independent risk factors for bone necrosis. According to discrimination analysis, patients younger than 30 years old and older patients with a fragmented flap had the highest risk of developing bone necrosis. CONCLUSIONS Development of bone flap necrosis is the main concern in long-term follow-up after cranioplasty with autograft. Patients younger than 30 years old and older patients with a fragmented flap may be candidates for an initial artificial bone substitute rather than autograft.

Comparison of Complications Following Cranioplasty Using a Sterilized Autologous Bone Flap or Polymethyl Methacrylate

“…Several authors have reported on the risk factors for developing BFR following CP with autologous bone. Schwarz et al28) found that younger than 30 years, the presence of a V-P shunt, and bone flap fragmentation were risk factors for BFR. In addition, Martin et al16) reported that the rate of BFR as 81.8% among 27 patients under 18-years of age who underwent CP with autologous bone after DC, following surgical revision in 54.4 %.…”

Scalp Tissue Expansion Above a Custom-Made Hydroxyapatite Cranial Implant to Correct Sequelar Alopecia on a Transposition Flap

“…The choice between autologous bone and alloplastic material for bone reconstruction in cranioplasty remains under debate. 6 Debate also exists concerning techniques for soft tissue recruitment when tissue is lacking over the scalp. 1,7,8 Among techniques, tissue expansion has been demonstrated to be safe when performed over the cranial bone, either before the cranioplasty procedure to increase the rate of success 1,9 or after cranioplasty, away from the implant, to correct sequelar alopecia.…”

Cranioplasty as the return-to-work factor – 112 patients with cranial defects treated in the Department of Neurosurgery at the Medical University Of Lodz

“…The second one involves implants where allogenic substances are involved such as metals, ceramics or plastics [3]. The patient's own bone is very often resorbed, sometimes causes autoagres sive reaction, and always requires additional operative field [4]. Metals have high thermal conduction and as such in various seasons they easily transmit the heat to or out of the body [5].…”