Donor- and recipient-site morbidity of vascularized fibular and iliac flaps for mandibular reconstruction: A systematic review and meta-analysis

Sequential free fibula transfers: Quality of life and systematic review

BACKGROUND

Successive osteoseptocutaneous fibula transfers for jaws reconstruction are rare but important options. This study contributes patient-reported and clinical outcomes, as well as systematically reviews all existing reports.

METHODS

All sequential fibula transfers performed by the senior author were reviewed from a prospectively managed database, including University of Washington quality of life (UWQoL). Systematic review was conducted in PubMed and Cochrane databases for similar publications.

RESULTS

Eighteen patients (average age 51.5 years) received sequential fibulas (mean 4.7 years between reconstructions). Secondary fibulas more often had benign indications (72.2% vs. 33.3%, p = .04), most commonly osteoradionecrosis (38.9%). At a mean follow-up of 30.5 months, the average interincisal distance increased from 21.8 to 27.6 mm, and 92.3% tolerated an oral diet following the second fibula. Eight patients completed the UW-QoL before and after the second fibula, and three prior to the first fibula. Composite physical function was significantly decreased from 96.7 prefibula reconstruction to 63.3 following the first (p < .001) and 64.2 after the second fibula (p < .001). There were no differences in other domains. The systematic review yielded six articles reporting 56 patients (mean 39 months between fibulas). Secondary fibulas were performed for repeat malignancy (45%) and osteoreadionecrosis (39%), resulting in elevated tube feeding from 20% following the first to 39% following the second, but overall high quality of life in two studies.

CONCLUSIONS

Sequential osteoseptocutaneous fibula reconstructions of jaws are often performed for benign indications such as osteoradionecrosis. Overall function and QoL are comparable with those following the first fibula transfer.

Midterm Donor Site Morbidity After Vascularized Free Fibula Flap Harvesting

BACKGROUND

Vascularized fibula grafts (VFGs) have become one of the most preferred grafts for the reconstruction of bone defects. However, despite the many advantages over other graft options, recipient and donor site morbidities are also common. Donor site morbidity has been reported at rates ranging from 5% to 67%. The aim of this study was to present a single-center series examining the clinical, functional, and radiologic aspects of donor site morbidity following VFG harvesting.

METHODS

The study included 69 patients who underwent biological reconstruction with VFG for bone tumors, avascular necrosis of the femoral head, or bone defects after trauma. Patients were evaluated functionally, clinically, and radiologically for donor site morbidity.

RESULTS

Donor site morbidity was observed in 33 of 69 patients (48%). The most complications were sensation deficits around the feet and ankles (20 of 69; 29%). Knee laxity was more common in patients who underwent osteoarticular fibular resection (P = .006).

CONCLUSION

We found VFG to be an effective method for the reconstruction of large bone defects, but associated with a relatively high rate of complications. Complications requiring surgical intervention were rare and the majority of patients did not have long-term functional limitations.

LEVEL OF EVIDENCE

Level IV, retrospective case series.

Bone Allograft Acid Lysates Change the Genetic Signature of Gingival Fibroblasts

Bone allografts are widely used as osteoconductive support to guide bone regrowth. Bone allografts are more than a scaffold for the immigrating cells as they maintain some bioactivity of the original bone matrix. Yet, it remains unclear how immigrating cells respond to bone allografts. To this end, we have evaluated the response of mesenchymal cells exposed to acid lysates of bone allografts (ALBA). RNAseq revealed that ALBA has a strong impact on the genetic signature of gingival fibroblasts, indicated by the increased expression of IL11, AREG, C11orf96, STC1, and GK-as confirmed by RT-PCR, and for IL11 and STC1 by immunoassays. Considering that transforming growth factor-β (TGF-β) is stored in the bone matrix and may have caused the expression changes, we performed a proteomics analysis, TGF-β immunoassay, and smad2/3 nuclear translocation. ALBA neither showed detectable TGF-β nor was the lysate able to induce smad2/3 translocation. Nevertheless, the TGF-β receptor type I kinase inhibitor SB431542 significantly decreased the expression of IL11, AREG, and C11orf96, suggesting that other agonists than TGF-β are responsible for the robust cell response. The findings suggest that IL11, AREG, and C11orf96 expression in mesenchymal cells can serve as a bioassay reflecting the bioactivity of the bone allografts.

Oral Cavity Reconstruction

This summary provides a concise overview of oral cavity reconstruction to optimize functional outcomes in the modern era. Soft tissue and osseous reconstruction options for a wide range of oral cavity sites including lip, oral tongue, floor of mouth, buccal, hard palate, and composite oromandibular resections are reviewed. The appropriate applications of primary closure, secondary intention, skin grafts, and dermal substitute grafts are included. Anatomic considerations, indications, contraindications, and complications of local, regional, and free flaps in oral cavity reconstruction are discussed. Specific defects and the appropriate options for reconstruction of those defects are delineated.

Donor site morbidity after computer assisted surgical reconstruction of the mandible using deep circumflex iliac artery grafts: a cross sectional study

BACKGROUND

Computer Assisted Design and Computer Assisted Manufacturing (CAD/CAM) have revolutionized oncologic surgery of the head and neck. A multitude of benefits of this technique has been described, but there are only few reports of donor site comorbidity following CAD/CAM surgery.

METHODS

This study investigated comorbidity of the hip following deep circumflex iliac artery (DCIA) graft raising using CAD/CAM techniques. A cross-sectional examination was performed to determine range of motion, muscle strength and nerve disturbances. Furthermore, correlations between graft volume and skin incision length with postoperative donor site morbidity were assessed using Spearman's rank correlation, linear regression and analysis of variance (ANOVA).

RESULTS

Fifteen patients with a mean graft volume of 21.2 ± 5.7 cm³ and a mean incision length of 228.0 ± 30.0 mm were included. Patients reported of noticeable physical limitations in daily life activities (12.3 ± 11.9 weeks) and athletic activities (38.4 ± 40.0 weeks in mean) following surgery. Graft volume significantly correlated with the duration of the use of walking aids (R = 0.57; p = 0.033) and impairment in daily life activities (R = 0.65; p = 0.012). The length of the scar of the donor-site showed a statistically significant association with postoperative iliohypogastric nerve deficits (F = 4.4, p = 0.037). Patients with anaesthaesia of a peripheral cutaneous nerve had a larger mean scar length (280 ± 30.0 mm) than subjects with hypaesthesia (245 ± 10.1 mm) or no complaints (216 ± 27.7 mm).

CONCLUSIONS

Despite sophisticated planning options in modern CAD/CAM surgery, comorbidity of the donor site following  iliac graft harvesting is still a problem. This study is the first to investigate comorbidity after DCIA graft raising in a patient group treated exclusively with CAD/CAM techniques. The results indicate that a minimal invasive approach in terms of small graft volumes and small skin incisions could help to reduce postoperative symptomatology. Trial registration Retrospectively registered at the German Clinical Trials Register (DRKS-ID: DRKS00029066); registration date: 23/05/2022.

Impact of Endothelial Progenitor Cells in the Vascularization of Osteogenic Scaffolds

The microvascular endothelial network plays an important role in osteogenesis, bone regeneration and bone tissue engineering. Endothelial progenitor cells (EPCs) display a high angiogenic and vasculogenic potential. The endothelialization of scaffolds with endothelial progenitor cells supports vascularization and tissue formation. In addition, EPCs enhance the osteogenic differentiation and bone formation of mesenchymal stem cells (MSCs). This study aimed to investigate the impact of EPCs on vascularization and bone formation of a hydroxyapatite (HA) and beta-tricalcium phosphate (ß-TCP)–fibrin scaffold. Three groups were designed: a scaffold-only group (A), a scaffold and EPC group (B), and a scaffold and EPC/MSC group (C). The HA/ß–TCP–fibrin scaffolds were placed in a porous titanium chamber permitting extrinsic vascularization from the surrounding tissue. Additionally, intrinsic vascularization was achieved by means of an arteriovenous loop (AV loop). After 12 weeks, the specimens were explanted and investigated by histology and CT. We were able to prove a strong scaffold vascularization in all groups. No differences regarding the vessel number and density were detected between the groups. Moreover, we were able to prove bone formation in the coimplantation group. Taken together, the AV loop is a powerful tool for vascularization which is independent from scaffold cellularization with endothelial progenitor cells’ prior implantation.