Bone flap replacement after a decompressive craniectomy is a low complexity procedure, but with complications that can negatively impact the patient\'s outcome. A better knowledge of the risk factors for these complications could reduce their incidence.
A retrospective review of a series of 50 patients who underwent bone replacement after decompressive craniectomy at a tertiary center over a 10-year period was performed. Those clinical variables related to complications after replacement were recorded and their risk factors were analyzed.
A total of 18 patients (36%) presented complications after bone flap replacement, of which 10 (55.5%) required a new surgery for their treatment. Most of the replacements (95%) were performed in the first 90 days after the craniectomy, with a tendency to present more complications compared to the subsequent period (37.8% vs 20%, p > 0.05). The most frequent complication was subdural hygroma, which appeared later than infection, the second most frequent complication. The need for ventricular drainage or tracheostomy and the mean time on mechanical ventilation, ICU admission, or waiting until bone replacement were greater in patients who presented post-replacement complications. Previous infections outside the nervous system or the surgical wound was the only risk factor for post-bone flap replacement complications (p = 0.031).
Postoperative complications were recorded in more than a third of the patients who underwent cranial bone flap replacement, and at least half of them required a new surgery. A specific protocol aimed at controlling previous infections could reduce the risk of complications and help establish the optimal time for cranial bone flap replacement.

BACKGROUND: Cranioplasty is the used method in neurosurgery for repairing cranial bone defects. In our environment, the most widely used material is cryopreserved autologous bone (ABCp).
OBJECTIVE: A retrospective observational study was proposed in order to analyze complications in patients who underwent decompressive craniectomy for brain trauma, with subsequent cranioplasty with ABCp.
METHODS: Patients who underwent cranioplasties with consecutive ABCp performed at our institution over a four-year period (2016-2019) with subsequent follow-up were included, collecting multiple variables in relation to the appearance of complications.
RESULTS: 113 cranioplasties were performed, of which 85.8% (n = 97) were performed with ABCp. Mainly with frontotemporoparietal bone defect (94.84%) performed late (> 3 months) in 91.76%. The complication rate was 16.49%, the most significant being the infection of the surgical site (n = 8, 8.24%), the presence of intracranial hematoma (n = 3, 3.09%) and the reabsorption of the autologous bone (n = 2, 2.06%), meriting surgical management in nine of them (9.27%).
CONCLUSIONS: ABCp is a valid and safe option, which meets the basic characteristics to consider it the ideal material, with an acceptable rate of complications, biocompatible, with osteogenic potential, adequate protection of the brain and decrease in surgery costs.
BACKGROUND: La craneoplastia es el método utilizado en neurocirugía para reparar los defectos óseos craneanos. En nuestro medio, el material utilizado mayormente es el hueso autólogo criopreservado (HACp).
OBJECTIVE: Realizamos un estudio retrospectivo observacional para analizar las complicaciones en pacientes sometidos a craniectomía descompresiva por trauma craneoencefálico y realización de craneoplastia con HACp.
UNASSIGNED: Se incluyeron pacientes que fueron sometidos a craneoplastias con HACp consecutivas realizadas en un periodo de 4 años (2016-2019) con seguimiento posterior, recabando múltiples variables en relación con la aparición de complicaciones.
RESULTS: Se realizaron 113 craneoplastias, de las cuales el 85.8% (n = 97) fueron realizadas con HACp, principalmente con defecto óseo frontotemporoparietal (94.84%), realizadas de forma tardía (> 3 meses) en el 91.76%. El índice de complicaciones fue del 16.49%, siendo las más significativas la infección del sitio quirúrgico (n = 8, 8.24%), la presencia de hematoma endocraneano (n = 3, 3.09%) y la reabsorción del hueso autólogo (n = 2, 2.06%), ameritando manejo quirúrgico en nueve ocasiones (9.27%).
CONCLUSIONS: El HACp es una opción válida y segura, la cual cumple con las características para considerarlo el material ideal, con un aceptable índice de complicaciones, biocompatible, con potencial osteogénico, adecuada protección encefálica y disminución de los costos de la cirugía.

Cranioplasty is a procedure routinely performed in neurosurgery. It is associated with significant morbidity and several types of postsurgical complications. The most common are infections, bone flap resorption and hematomas. Atypical facial pain has not been documented yet as a potential postoperative complication. We present a case of atypical facial pain reported at inmediate postoperative period after cranioplasty. The pain was refractory to medical treatment and sphenopalatine ganglion block. Eventually, the pain totally disappeared after surgical revision of the cranial implant.

To report a case of post-surgical encephalocele through craniotomy burr holes following the resection of a meningioma of the posterior fossa. A 49-year-old female presented in the emergency room with cephalea. The MRI showed a meningioma of the convexity of the posterior fossa. A resection was performed and the bone flap replaced. The patient recovered uneventfully and was discharged. After 30 days the patient consulted referring cephalea, vomiting and imbalance. Brain MRI revealed a trans-cranial cerebellar herniation through the craniotomy burr holes. An urgent surgery was performed to repair the encephalocele. Post-surgical brain MRI was performed and did not show complications. Post-surgical encephalocele is an uncommon complication after the resection of a posterior fossa lesion. To avoid this complication, it is recommended thorough dural and bony closure, particularly in the posterior fossa surgeries and in high-risk patients.

BACKGROUND: Cranioplasty is carried out for cosmetic reasons and for protection, but it may also lead to some neurological improvement after the bone flap placement. Complications of cranioplasty are more frequent than expected for a scheduled neurosurgical procedure. We tried to identify factors associated with both complications and improvement after cranioplasty.
METHODS: We prospectively studied the cranioplasties performed in our hospital from November 2009 to November 2013. Patients whose initial reason for bone removal was tumor infiltration were excluded. Demographic, clinical and radiological data were collected. The NIH Stroke Scale and Barthel Self-Care Index scores were obtained both before and within 72 h after cranioplasty. The outcome measures were the occurrences of complications and clinical improvement.
RESULTS: Fifty-five cranioplasties were performed. The material used for the cranioplasty was autologous bone in 42 cases, polyetheretherketone (PEEK) in 7 and methacrylate in 6. The average size of the bone defect was 69.5 (19.5-149.5) cm2. The time elapsed between decompressive craniectomy and cranioplasty was 309 (25-1217) days. There were 10 complications (7 severe and 3 mild), an 18.2% complication rate. Statistically significant risk factors of complications were identified as a Barthel≤70 (Odds ratio [OR] 22; 2.5-192; P=0.005), age over 45 years (OR 13.5; 1.5-115; P=0.01) and early surgery (≤85 days; OR 8; 1.69-37.03, P=0.004). After multivariate analysis, Barthel≤70 and age over 45 years remained independent predictors of complications. Twenty-two (40%) of the 55 patients showed objective improvement. Early surgery (<85 days) increased the likelihood of improvement (OR 4.67; 1.05-20.83; P=0.035). Larger bone defects seemed to be related with improvement, but differences in defect size were not statistically significant (75.3 vs 65.6 cm2; P=0.1).
CONCLUSIONS: The complication rate of cranioplasty is higher than for other elective neurosurgical procedures. Older age, poorer functional situation (worse Barthel index score) and early surgery (≤85 days) are independent risk factors for complications. However, cranioplasty produces clinical benefits beyond protection and esthetic improvement. Earlier surgery and larger bone defects seem to increase the likelihood of clinical improvement.

The current increasing use of decompressive craniectomy carries the implicit appearance of complications due to alterations in both intracranial pressure and in the hydrostatic-hemodynamic equilibrium. Paradoxical transtentorial herniation represents a rare manifestation, included in \"trephine syndrome\", extremely critical but with relatively simple treatment. We present the case of a 56-year-old woman with no interesting medical history, who, after an olfactory groove meningioma surgery, presented a haemorrhage located in the surgical area with an important oedema. The patient required a second emergency surgery without any chance of conserving the cranial vault. During the post-operational period, great neurological deterioration in orthostatic position was noticed, which resolved spontaneously in decubitus. This deficit was resolved with bone replacement afterwards. We discuss possible predisposing factors and aetiologies of this pathology.