Indications, fixation principles, and donor sites for vascularized bone flap arthrodesis in the setting of tumor and osteomyelitis.

Biological and clinical implications of autologous bone flap preservation strategies after decompressive craniectomy: a systematic review and meta-analysis.

Cranioplasty is performed to restore the bone flap after previous brain surgery or trauma. Despite its elective nature, patients may be at risk for complications. Our study analyzes predictors of adverse events after cranioplasty and compares outcomes among patients undergoing very-early and standard cranioplasty. Patients who underwent cranioplasty were retrospectively identified from the TriNetX Research Network. A Cox proportional hazards model was used to assess the risk of mortality, surgical site infection (SSI), and need for revision cranioplasty. Propensity score matching was performed to compare adverse events based on timing of cranioplasty: very-early (≤1 month) and standard (>1 month). In total, 22 347 patients were included. Risk factors for mortality were being overweight/obese (hazard ratio [HR]: 1.15, 95% CI: 1.04-1.28, P < .01), acute kidney failure/chronic kidney disease (HR: 1.28, 95% CI: 1.15-1.42, P < .001), long-term steroid use (HR: 1.47, 95% CI: 1.24-1.75, P < .0001), and history of opioid-related disorders (HR: 1.29, 95% CI: 1.01-1.65, P < .05). Increasing risk of SSI was observed across different age groups. Risk factors for revision cranioplasty were White race (HR: 0.74, 95% CI: 0.62-0.89, P < .01), diabetes mellitus (HR: 1.22, 95% CI: 1.05-1.42, P < .01), and acute kidney failure/chronic kidney disease (HR: 1.30, 95% CI: 1.11-1.52, P < .001). After propensity score matching, 2223 patients were included in each cohort. The very-early cohort had higher risk for all-cause mortality, use of critical care services, sepsis, pneumonia, urinary tract infection, hydrocephalus, epidural hemorrhage, acute kidney failure, headache, nausea, and vomiting compared with the standard cohort. The very-early cohort also had lower risk for revision cranioplasty, SSI, and infection of prosthetic devices. Demographic variables, comorbid conditions, and procedure characteristics predict adverse events after cranioplasty. Very-early cranioplasty may carry increased risk for mortality but decreased risk for revisions compared with standard cranioplasty.

Electroencephalography (EEG) is widely used in both research and clinical settings, yet its accuracy can be significantly impacted by subject-specific anatomical anomalies such as brain lesions and skull defects. This study investigates the effects of glioma-related brain lesions and craniotomy-induced bone discontinuities on scalp-recorded EEG signals. To do this, single- and multi-source simulations were created using individualized forward models with and without these structural anomalies. We assessed changes in signal amplitude and topography, and identified the most affected electrodes. Furthermore, real EEG recordings were also analyzed longitudinally to evaluate how these anomalies influence the topography and source localization of early auditory evoked responses (P1 and N1 ERP components). Both single- and multi-source simulations showed that the distortions in the EEG signals depend on the location of the neural source in relation to the location of the lesion. Electrode-level analyses showed that these distortions were most pronounced at the electrodes near the bone flap, and thus near the lesions. Real ERP data supported these findings: a subject with a lesion near the auditory cortex showed notable topographic deviations longitudinally for the P1 and N1 ERP components, while a subject with a frontal lesion showed minimal changes in the scalp EEG. These results highlight the need to include detailed brain and skull anatomy in EEG models, especially in studies that track longitudinal changes in clinical populations.

Combining cryopreserved autografts and vascularized bone flap for craniofacial defect reconstruction in fibrous dysplasia: a case report

Bone flap replacement restores cranial protection and contour in neurosurgery. Accidental intraoperative contamination, particularly dropped bone flaps, poses risks of infection. Management strategies are heterogeneous and lack standardized guidelines. To systematically review reported strategies for managing dropped cranial bone flaps, focusing on surgical context, decontamination methods, operative impact, antibiotic use, and outcomes. A systematic review was conducted in accordance with PRISMA guidelines. Relevant databases were searched from inception to September 2025. Eligible studies described strategies for intraoperative bone flap decontamination and reported at least one clinical outcome. Data extracted included study type, sample size, surgical context, decontamination strategy and duration, post-operative antibiotic regimen, follow-up period, and outcomes. Three retrospective series comprising 48 cases met the inclusion criteria. Flaps were dropped during elevation, transfer, drilling, reinsertion, and plating. Chemical decontamination-typically saline irrigation, povidone iodine ± hydrogen peroxide, and antibiotic soak-was most common, adding 15-30 min to surgery, with no post-operative infections reported. Autoclaving ensured sterility but prolonged the operative time (37 min), and carried the risk of partial flap resorption. Discarding the flap with immediate cranioplasty was reserved for non-salvageable cases, incurring the longest delay (39 min). Dropped cranial bone flaps are rare but have clinically significant implications. Available evidence, limited to small series and surveys, show comparable outcomes between chemical decontamination, autoclaving, and discarding the flap followed by cranioplasty. Standardized, evidence-based guidelines are lacking, underscoring the need for multicenter prospective studies.

Background: Achieving watertight dural closure in posterior fossa surgery is often challenging due to the anatomical complexity of this region, particularly when suturing is not feasible near critical venous structures. These circumstances increase the risk of cerebrospinal fluid (CSF) leakage, a well-recognized complication. Traditional single-layer techniques may be insufficient to achieve a watertight seal. To address this limitation, we developed a novel multilayer duraplasty method, termed the “Sandwich Technique,” which combines an absorbable collagen matrix with autologous fascia. Methods: A 69-year-old woman with a large tentorial meningioma and obstructive hydrocephalus underwent tumor resection. Intraoperatively, a wide dural defect adjacent to the transverse sinus was identified, where primary closure was not feasible. Reconstruction was performed using the three-layer Sandwich Technique: Step 1, an inlay DuraGen ® sheet placed subdurally and sutured to the tentorium; Step 2, an overlay of autologous fascia lata; and Step 3, an onlay DuraGen ® sheet folded over the fascia and secured with the bone flap. Fibrin glue was applied between each layer to reinforce adhesion. Results: Postoperative imaging confirmed a watertight closure with no evidence of CSF leakage. The patient experienced no complications, and follow-up imaging at 2 months demonstrated a stable reconstruction. Conclusion: The Sandwich Technique provides a simple, reproducible option for dural repair in the posterior fossa when suturing is technically difficult. This multilayer approach, which integrates synthetic and autologous materials, allows tension-free watertight closure and may represent a valuable adjunct in neurosurgical dural reconstruction.

Background: Decompressive craniectomy (DC) is a life-saving intervention for refractory intracranial pressure (ICP). While outcomes in adults are well documented, pediatric data, especially concerning pupillomotor dysfunction, remain limited. Anisocoria is generally considered a marker of severe neurological compromise, but its clinical relevance in children undergoing DC has not been adequately studied. Methods: We retrospectively reviewed 25 pediatric patients treated with DC between 2004 and 2024. Demographic, radiological and clinical data included age, sex, hospital stay, operative time, etiology, side of craniectomy, preoperative midline (ML) shift, Marshall score, Rotterdam score, Glasgow Coma Scale (GCS) and pupillary status before surgery. Functional outcomes were assessed using the pediatric version of the Glasgow Outcome Scale Extended (pGOS-E) at discharge, after 3 months, 1, 2 and 4 years. Results: The majority of patients were school-aged children with a median age of 10 (range 0-17) years. Traumatic brain injury accounted for 16 cases and represented the leading etiology for DC. Pupillomotor dysfunction (anisocoria or bilateral fixed pupillary dilatation) was observed in 15 of 25 patients, 47% of whom died during hospitalization, demonstrating a significant association with in-hospital mortality (p = 0.02). However, survivors with primary pupillomotor dysfunction demonstrated a favorable recovery at 12 months with a median pGOS-E of 6 (range 4-8), indicating moderate disability. A preoperative ML-shift > 5 mm was not associated with lower pGOS-E scores during follow-up (p > 0.05). Bone flap autolysis was observed in 12 out of 14 children (86%) receiving autologous cranioplasty, and 8 (57%) patients required revision surgery with synthetic material. Conclusions: In pediatric patients, pupillomotor dysfunction is associated with higher early mortality but does not reliably exclude favorable long-term outcomes. Compared with adult cohorts, children appear to have a greater potential for neurological recovery, suggesting that severe initial clinical findings alone should not preclude timely surgical intervention.

Bone flap fixation with clamp-like devices or with titanium plates and screws: A cost-minimization analysis.

In-situ bone flap combined with a nasoseptal flap or a free mucosa flap for skull base reconstruction after endoscopic resection of craniopharyngiomas: A series of 115 cases.

The main objective of this study was to assess the safety and efficacy of a polymeric clamp-like device (Cranial LOOP) to fix the bone flap after a craniotomy in pediatric patients. A secondary objective was to assess the safety and efficacy of this device in children younger than 3years old (off-label). Follow-up visits and CT scans from 60 pediatric patients in which the craniotomy had been fixed with Cranial LOOP were retrospectively analyzed to assess bone stability, growth, alignment and fusion, esthetic outcomes, and postoperative complications. All the registered patients had adequate bone stability, growth, and alignment and satisfactory esthetic outcomes. Most patients (90.5%) had bone fusion from 1 year after surgery. There were no related postoperative complications during the follow-up. Off-label patients had the same results in all the assessed variables as the global population. Cranial LOOP is a safe and effective method to fix craniotomies in pediatric patients that allows adequate bone growth and fusion. Cranial LOOP can be safely used in children younger than 3years old with good results.

Metopic craniosynostosis causes characteristic cranial deformities such as a keel-shaped forehead, known as trigonocephaly. Mild trigonocephaly refers to cases of metopic craniosynostosis in which the cranial deformity is generally mild. The authors report a case of mild trigonocephaly accompanied by an atypical horizontal constricting ring of the skull that was successfully treated surgically. The patient was a 3-month-old boy with no notable medical history who presented to a pediatric clinic with frontal prominence. Computed tomography (CT) revealed premature fusion of the metopic suture, and he was referred to the authors' department for surgical treatment. A midline frontal ridge was observed but the keel-shaped forehead was not prominent, and the patient was diagnosed with mild trigonocephaly. Mild depression was observed in the temporal regions, and CT demonstrated a horizontal constricting ring of the skull (circumferential depression) extending approximately three-quarters of the way from the frontal region to both temporal areas. At 11 months of age, 1-stage cranial reconstruction was performed for mild trigonocephaly, along with correction of the constricting deformity. Through a coronal incision, the supraorbital bar and frontal bone flap were removed and reshaped. The parietal and temporal bones posterior to the frontal bone flap were barrel-staved, and the depressed bone fragments were elevated to reconstruct the constricted region. Postoperatively, the frontal contour improved, and the constricting ring observed before surgery resolved, resulting in an overall satisfactory cranial shape. One year after surgery, no signs of developmental delay or neurological impairment were observed. The authors experienced a rare case of mild trigonocephaly accompanied by an atypical horizontal constricting ring of the skull. Cases of nonsyndromic craniosynostosis with a horizontal constricting ring are extremely rare, and to our knowledge, none have been previously reported. Possible etiologies include an amniotic constriction band, a constricting ring caused by squamosal suture fusion as seen in cloverleaf skull, or compensatory deformation associated with restricted cranial growth; however, the exact mechanism remains unclear. In the present case, cranial reconstruction successfully improved the deformity, though long-term follow-up is necessary.

Immediate Postoperative Outcomes of Burr-Hole versus Bone Flap: A Hounsfield Unit Threshold in Subacute Subdural Hematoma.

Expansive Craniotomy versus Standard Decompressive Craniectomy in Refractory Intracranial Hypertension: A Systematic Review and Meta-Analysis.

Polymethylmethacrylate Versus Autologous Bone Flap Reconstruction After Retrosigmoid Vestibular Schwannoma Surgery: Impact on Wound Healing and Patient Satisfaction.

Guidelines in Practice: Autologous Tissue Management.

Avascular necrosis (AVN) of the proximal pole is a well-known complication of scaphoid fractures. Avascular necrosis is poorly understood, including the transition from ischemia to necrosis, optimal treatment, and why some AVN heals but others do not. The primary purpose of this study is to evaluate patient-related factors that are associated with healing outcomes in individuals with proximal pole AVN following scaphoid fractures. This is a retrospective review of all patients diagnosed with scaphoid proximal pole AVN secondary to a fracture from 2018 to 2024 in a single center. Patient baseline characteristics and comorbidities at time of diagnosis were collected. If the patient underwent surgical management, procedural factors were collected. The primary outcome was AVN healing after 4 months of follow-up. A total of 62 patients met inclusion criteria. Thirty of 62 (48.4%) went onto proximal pole AVN resolution. Hyperlipidemia (P = .030), advanced age at time of diagnosis (P = .038), and elevated body mass index (BMI) (P = .026) were independent factors associated with lack of AVN healing. For patients who underwent surgical management, there was no significant difference in healing outcomes between use of a nonvascularized, or no graft, and use of a vascularized bone flap (P = .115, P = .886, respectively). Hyperlipidemia, elevated BMI, and advanced age are patient factors negatively associated with scaphoid proximal pole AVN healing-key information for accurately assessing patient prognosis. For surgical management, the choice of a vascularized bone, nonvascularized bone graft, or no graft does not significantly impact AVN healing.

Severe Gustilo-III foot injuries that combine segmental bone loss with extensive soft tissue damage remain challenging. One-stage reconstruction with a free fibular vascularized bone flap (FVBF) or free iliac vascularized bone flap (IVBF) offers the advantages of immediate skeletal stability, soft tissue resurfacing, and early mobilization, but contemporary outcome data are limited. From December of 2000 to November 2021, 6 patients who sustained from severe traumatic metatarsal, tarsal bone, and soft tissue defects were treated with a FVBF or IVBF incorporating soft tissue was used to reconstruct the metatarsal/tarsal bones and the soft tissue defect. Demographics, defect characteristics, perioperative variables, time to weightbearing, radiographic union, and complications were analyzed. Systematic literature review was performed to derive an evidence-graded reconstructive framework for managing Gustilo-Anderson type III open foot fractures. Median length of follow-up is 24 months (range: 13 months to 2 years); all patients were able to walk independently and have returned to work. Six patients (mean age 32.8 ± 12.12 years) with defects of 8 to 22 cm were included. Partial weightbearing began at postoperative 10 weeks and mean return-to-work interval was 9.08 months. One partial muscle/skin necrosis (16.6%), 1 osteomyelitis (16.6%), and 1 venous congestion (16.6%) were observed postoperatively. No flap failure, nonunion, gait disturbance, instability, or amputation occurred. In this small consecutive series, single-stage free FVBF/IVBF reconstruction for Gustilo-Anderson type III foot injuries showed satisfactory union and a low infection rate. These findings support free FVBF/IVBF as a promising reconstructive strategy for complex foot trauma.

Objective: To explore the efficacy of free lateral arm tissue flap in repairing complex finger wounds. Methods: This study was a retrospective case series study. From January 2020 to December 2023, 8 patients with complex finger wounds who met the inclusion criteria were admitted to the 920th Hospital of Joint Logistic Support Force of PLA, including 5 males and three females, aged 24 to 56 years. There were 4 cases with multi-finger skin defects; there were 4 cases with single-finger skin combined with bone defects, three of whom were complicated with extensor tendon defects. The size of skin defects was 2.5 cm×2.0 cm to 8.0 cm×3.5 cm, and the size of bone defects was 1.5 cm×1.0 cm×1.0 cm to 2.0 cm×1.5 cm×1.0 cm. Five cases underwent emergency extended debridement and simultaneous transplantation of free lateral arm tissue flap for repair; the remaining three patients underwent extended debridement in stage Ⅰ and free lateral arm tissue flap transplantation for repair in stage Ⅱ. Four patients each underwent resection of lobulated flaps and chimeric osteocutaneous flaps, including 4 cases carrying the posterior arm cutaneous nerve and three cases having their extensor tendons being reconstructed with the triceps brachii aponeurosis. The size of skin flaps was 3.0 cm×2.5 cm to 9.0 cm×4.0 cm, and the size of bone flaps was consistent with the size of bone defects. The donor site wounds of skin flaps and bone flaps were closed with interrupted sutures. Postoperatively, the survival status of the tissue flaps was observed, and the pedicle division status of the lobulated flaps was recorded. At the final follow-up, the following parameters were assessed and documented: the appearance and texture of skin flaps, the sensory recovery of the affected finger transplanted with the posterior arm cutaneous nerve evaluated using the British Medical Research Council sensory function assessment criteria, the dorsiflexion of the affected finger transplanted with the triceps brachii aponeurosis, the survival of the bone flaps confirmed via X-ray examination, the scar formation at the donor sites of skin flaps, and the function of the affected fingers evaluated based on the trial standard for functional evaluation of the upper limb of the Hand Surgery Society of the Chinese Medical Association. Results: Postoperatively, the tissue flaps survived well. The pedicles of the lobulated flaps were successfully divided under local anesthesia 4 weeks after surgery. The follow-up duration ranged from 10 to 24 months, with an average of 13.5 months. At the final follow-up, the color and texture of the skin flaps were good, the sensation of the affected fingers transplanted with posterior arm cutaneous nerve recovered to level S2 or S3, the affected fingers transplanted with triceps brachii aponeurosis all achieved limited improvement in dorsiflexion, X-ray examination showed that the bone flaps survived, linear scars formed at the donor sites of skin flaps after wound healing, and the function of the affected fingers was evaluated as excellent in 5 cases and good in three cases. Conclusions: The lateral arm tissue is rich in perforators and has few anatomical variations, which can be prepared into lobulated flaps and chimeric osteocutaneous flaps for repairing complex finger wounds. The surgical operation is relatively simple, and the appearance and function of the donor and recipient sites are fairly good after surgery.

Background: Craniotomy involves creating multiple burr holes followed by the opening of a bone flap. After the intracranial procedure, the bone flap is replaced (osteoplasty), but burr hole defects remain and may lead to scalp depressions over time. This study evaluates the effectiveness of using a graft combination of bovine scaffold material and autologous calvarial bone dust for burr hole defect closure in calvarial osteoplasty.Methods: The scaffold was derived from the epiphysis of bovine cancellous femur bone, prepared by the tissue bank of Dr. Soetomo General Hospital, and adjusted to fit burr hole defects. Four patients underwent grafting with this combination during osteoplasty. All patients were followed up and evaluated at least 1 year after graft placement. Clinical assessment focused on scalp depressions, while head computed tomography (CT) scans were used to evaluate bone integration between the calvarial bone and the graft.Results: Among four patients, one showed scalp depression at the graft site, while the other three had no visible indentations. CT scans demonstrated that the three cases without scalp depression have intact grafts with cortical thickening in some areas. The single case with depression exhibited graft resorption and lytic bone changes. Importantly, no signs of graft rejection or allergic reactions were observed in any patient.Conclusion: This study suggests that the combination of bovine scaffold material and autologous calvarial bone dust in burr hole defect closure during calvarial osteoplasty can prevent scalp depression in the defect area.