Partial and Total Flap Failure after Fibula Free Flap in Head and Neck Reconstructive Surgery: Retrospective Analysis of 180 Flaps over 19 Years

Risk Factors for Plate Infection, Exposure, and Removal in Mandibular Reconstruction

OBJECTIVE

Mandibular plate reconstruction (MPR) is often indicated after tumor ablation, osteoradionecrosis excision, and traumatic bone loss to restore oral functionality and facial cosmetics. There are limited analyses identifying risk factors that lead to plate infection (PIn), exposure, and removal ("plate complications").

STUDY DESIGN

Retrospective cohort study.

SETTING

Academic tertiary medical center.

METHODS

Patients who underwent MPR from 2013 to 2022 were identified. Risk factors for plate complications were analyzed based on demographic, clinical, intraoperative, and postoperative factors. Multivariable analysis was conducted with logistic regression. Survival analysis was conducted with a Cox model.

RESULTS

Of the 188 patients analyzed, 48 (25.5%) had a plate complication [infection: 22 (11.7%); exposure: 23 (12.2%); removal: 35 (18.6%)]. Multivariate analysis revealed predictive associations between at least 1 plate complication and the following variables: smoking status, soft tissue defect size, number of plates, average screw length, and various postoperative complications. Other associations approached the threshold for significance. Prior and adjuvant radiation therapy, type of free flap, stock versus custom plates, and perioperative antibiotic prophylaxis regimens were not associated with plate complications. No plate complication was independently associated with lower overall survival. PIn (hazard ratio, HR: 7.99, confidence interval, CI [4.11, 15.54]) and exposure (HR: 3.56, CI [1.79, 7.08]) were independently associated with higher rates of plate removal.

CONCLUSION

Plate complications are relatively common after MPR. Smoking history, specific disease characteristics, hardware used during surgery, and postoperative complications may help identify higher-risk patients, but additional larger-scale studies are needed to validate our findings and resolve discrepancies in the current literature.

The Tumor Risk Score (TRS) - next level risk prediction in head and neck tumor surgery

PURPOSE

Head and neck cancer surgery often requires postoperative monitoring in an intensive care unit (ICU) or intermediate care unit (IMC). With a variety of different risk scores, it is incumbent upon the investigator to plan a risk-adapted allocation of resources. Tumor surgery in the head and neck region itself offers a wide range of procedures in terms of resection extent and reconstruction methods, which can be stratified only vaguely by a cross-disciplinary score. Facing a variety of different risk scores we aimed to develop a new Tumor Risk Score (TRS) enabling anterograde preoperative risk evaluation, resource allocation and optimization of cost and outcome measurements in tumor surgery of the head and neck.

METHODS

A collective of 547 patients (2010-2021) with intraoral tumors was studied to develop the TRS by grading the preoperative tumor size and location as well as the invasiveness of the planned surgery by means of statistical modeling. Two postoperative complications were defined: (1) prolonged postoperative stay in IMC/ICU and (2) prolonged total length of stay (LOS). Each parameter was analyzed using TRS and all preoperative patient parameters (age, sex, preoperative hemoglobin, body-mass-index, preexisting medical conditions) using predictive modeling design. Established risk scores (Charlson Comorbidity Index (CCI), American Society of Anesthesiologists risk classification (ASA), Functional Comorbidity Index (FCI)) and Patient Clinical Complexity Level (PCCL) were used as benchmarks for model performance of the TRS.

RESULTS

The TRS is significantly correlated with surgery duration (p < 0.001) and LOS (p = 0.001). With every increase in TRS, LOS rises by 9.3% (95%CI 4.7-13.9; p < 0.001) or 1.9 days (95%CI 1.0-2.8; p < 0.001), respectively. For each increase in TRS, the LOS in IMC/ICU wards increases by 0.33 days (95%CI 0.12-0.54; p = 0.002), and the probability of an overall prolonged IMC/ICU stay increased by 32.3% per TRS class (p < 0.001). Exceeding the planned IMC/ICU LOS, overall LOS increased by 7.7 days (95%CI 5.35-10.08; p < 0.001) and increases the likelihood of also exceeding the upper limit LOS by 70.1% (95%CI 1.02-2.85; p = 0.041). In terms of predictive power of a prolonged IMC/ICU stay, the TRS performs better than previously established risk scores such as ASA or CCI (p = 0.031).

CONCLUSION

The lack of a standardized needs assessment can lead to both under- and overutilization of the IMC/ICU and therefore increased costs and losses in total revenue. Our index helps to stratify the risk of a prolonged IMC/ICU stay preoperatively and to adjust resource allocation in major head and neck tumor surgery.

Predictive Factors for Delayed Recovery From Anesthesia in Patients Receiving Free Vascularized Flap Reconstruction for Head and Neck Defects: A Retrospective Cohort Study

OBJECTIVE

Free flap reconstruction for head and neck defects is currently a common procedure. This study aimed to create and validate a predictive model for identifying patients at risk of delayed recovery from anesthesia after free flap reconstruction for head and neck defect.

METHODS

Electronic medical records from all patients were retrospectively collected. The primary outcome variable was delayed recovery from anesthesia. The least absolute shrinkage and selection operator regression model was employed to identify the most relevant features, followed by the construction of a nomogram model using multivariable logistic regression analysis. The discriminatory power, calibration, and clinical utility of the nomogram model were assessed using receiver operating characteristic curve analysis, calibration curve analysis, and decision curve analysis, respectively.

RESULTS

This novel nomogram model incorporated 4 predictors for delayed recovery from anesthesia: preoperative albumin, intraoperative fresh frozen plasma infusion, preoperative platelet-to-lymphocyte ratio, and duration of intraoperative hypotension. The area under the receiver operating characteristic curve (area under the curve) for the nomogram model was determined to be 0.821 (95% CI: 0.803-0.836). After internal validation, the corrected area under the curve was found to be 0.768 (95% CI: 0.639-0.812). In addition, the model exhibited well-fitted calibration curves and demonstrated favorable clinical usability as indicated by the calibration curve and decision curve analysis curve.

CONCLUSION

The authors created and validated a novel predictive model utilizing a limited number of 4 predictors, yet exhibiting commendable predictive performance. This innovative tool holds the potential to mitigate delayed recovery from anesthesia and enhance the efficient allocation of medical resources.

Platelet-Rich Fibrin Treatment Evaluation in Patients with Medication-Related Osteonecrosis of the Jaw and Osteoradionecrosis

Background. Medication-related osteonecrosis of the jaw (MRONJ) and osteoradionecrosis (ORN) are associated with severe disability and continuous pain, both of which are very difficult to control. This study aims to evaluate the outcome of platelet-rich fibrin (PRF) treatment compared to iodoform gauze packing and the primary suture of oral mucosa in patients with both MRONJ and ORN. Methods. Patients suffering from MRONJ and ORN who were treated in the Oral and Maxillofacial Surgery Clinic of Cluj-Napoca in the last 10 years were selected for this study from the hospital database. Results. PRF treatment proved to be a reliable method to help heal the necrotic bone sites. High-ASA risk patients and immunosuppressed patients are more prone to recurrence and persistent signs and symptoms. Intravenous bisphosphonates produce more intense symptomatology compared to oral administration. The posterior mandible is more difficult to treat compared to other sites. Conclusions. The quality of life of MRONJ and ORN patients may be improved by a protocol that reduces pain and hospitalization.

Early outcomes of osteofascial versus osteocutaneous fibula free flap mandibular reconstruction

BACKGROUND

This study compares early outcomes of osteofascial fibula free flap (OF-FFF) with donor-site primary closure and osteocutaneous (OC) FFF with donor-site skin grafting in segmental mandibular reconstruction.

METHODS

A retrospective chart review of FFF mandibular reconstruction patients (2006-2022) divided into OF-FFF and OC-FFF groups. Clinical data, operative parameters, and early postoperative outcomes (≤ 90 days) were analyzed.

RESULTS

The study included 67 patients (39 OF-FFF, 28 OC-FFF). OF-FFF had significantly lower donor-site complications (12.8% vs. 53.6%, p < 0.001) and revision surgeries (7.7% vs. 35.7%, p = 0.004) compared to OC-FFF. Recipient-site (28.2% vs. 25%, p = 0.77) and flap (15.4% vs. 17.9%, p > 0.99) complications were comparable.

CONCLUSIONS

OF-FFF mandibular reconstruction with donor-site primary closure is a safe and reliable technique associated with superior donor-site and comparable flap and recipient-site outcomes to OC-FFF, thus may be considered as a viable alternative to OC-FFF for selected patients.

Use of scapular tip flaps in the reconstruction of head and neck defects: a systematic review and meta-analysis

Scapular tip flaps (STF) may be used as an alternative to traditional methods of reconstruction of head and neck cancer (HNC) defects. This study aimed to establish the success and complication rates for STF in HNC reconstruction. A literature search was conducted on PubMed, BMJ Journals, DARE, EMBASE databases and Cochrane (CENTRAL) register. (Registry CRD42023428012). A total of 23 studies fulfilled the inclusion criteria with 474 patients who underwent reconstructive procedures using the STF. 100% of STF used were free flaps (STFFs). The most common reason for reconstruction was following malignancy (81.4%, n = 386). The pooled success rates in all studies using scapular tip flaps in head and neck reconstruction was 99% (95% CI, 97 to 100, p = 1.00; I2 = 0). Pooled total complication rates were 38% (95% CI, 25 to 51, p < 0.01; I2 = 90%). 19.6% required return to theatre with only 1.5% being for repeat flap coverage. The STF demonstrated an overall success rate of 99%. This is higher than other documented success rates with mainstay flaps for HNC defect reconstruction. Complication and re-operation rates were also like recorded rates. This review demonstrates the advantage of STF as a safe and versatile reconstructive option for HNC related defects. Evaluation of the literature is limited by poor-quality studies and comparability bias.

Advances in Regenerative Dentistry Approaches: An Update

Regenerative dentistry is a rapidly evolving field in dentistry, which has been driven by advancements in biomedical engineering research and the rising treatment expectations and demands that exceed the scope of conventional approaches. Tissue engineering, the foundation of regenerative dentistry, mainly focuses on 3 key components: stem cells, bioactive molecules, and scaffolds. Dental tissue-derived stem cells are especially significant in this regard due to their remarkable properties. Regenerative techniques have provided novel approaches to many conventional treatment strategies in various disciplines of dentistry. For instance, regenerative endodontic procedures such as pulp revascularisation have provided an alternative approach to conventional root canal treatment. In addition, conventional surgical and nonsurgical periodontal treatment is being taken over by modified approaches of guided tissue regeneration with the aid of 3-dimensional bioprinting and computer-aided design, which has revolutionised oral and maxillofacial tissue engineering. This review presents a concise overview of the latest treatment strategies that have emerged into clinical practice, potential future technologies, and the role of dental tissue-derived stem cells in regenerative dentistry.

Heparin regimes in head and neck cancer flap surgery: A retrospective cohort study of free flap complications graded by Clavien-Dindo

The purpose of the current study was to compare two different antithrombotic protocols for free flap reconstruction in head and neck squamous cell carcinoma (HNSCC) patients. Postoperative complications were graded using the Clavien-Dindo (CD) classification and compared between the two groups: the low-molecular-weight heparin (LMWH) group (n = 57) and the unfractionated heparin (UFH) group (n = 59). Patients with HNSCC from January 2010 to January 2022 were included. A total of 116 patients with a mean age of 60.46 years (range 43-83 years) were included in this study. In all, 81 were male (69.8%), and 35 were female (30.2%). Most patients (48.3%) had only grade 1 or 2 complications. CD grades (1-5) were similar between the two groups. Flap loss occurred in 2 patients (1.7%) in the LMWH group (p = 239). Prognostic factors of flap loss were high BMI, hypertension, high T stage, and high N stage. No differences were found between the groups in regard to age, sex, operating times, flap source, recipient vessels and overall complications. The results of this study demonstrate that UFH was as safe and effective as LMWH regarding postoperative complications. Free flap surgery is safe and effective for head and neck reconstruction.

The volume-outcome relationship in free-flap reconstruction: A nationwide study based on the Clinical Database

BACKGROUND

The association between successful reconstructive surgery with a free flap and hospital volume has not been well established. This study was designed to retrospectively analyze the outcome of free-flap surgery registered in a nationwide surgical registration system in Japan to clarify the relationship between free-flap survival and facilities' average annual number of free-flap surgeries.

METHODS

We analyzed data from 19,482 free flaps performed during 2017-2020 at 407 facilities throughout Japan. After adjusting for sex, age, and disease classification that differ between the groups, we examined the differences in the flap survival rates among the different facilities in terms of the average number of free-flap surgeries performed annually.

RESULTS

The total overall necrosis rate was 2.8%. Of all procedures, 14.9%, 12.9%, 33.4%, and 38.8% were performed at facilities with an average number of free-flap procedures <10, 10-19, 20-49, and ≥ 50 per year, respectively, and the respective rates of total necrosis were 6.0%, 3.8%, 2.1%, and 1.7%, respectively. The odds ratios and 95% confidence intervals of flap necrosis for facilities with ≥ 50 cases per year relative to those <10 were 2.70 (1.98-3.68) for nonbreast reconstruction cases and 5.72 (2.77-11.8) for breast reconstruction cases.

CONCLUSION

This analysis of a nationwide plastic surgery database showed that free-flap surgeries in institutions with a low average annual number of free-flap surgeries had a higher risk of total necrosis. Measures should be taken to either aggregate cases into high-volume centers or improve management at low-volume centers.

Nitroglycerin improves the visibility of fibula-free flap perforators on computed tomography angiography in patients with oral or maxillofacial lesion

PURPOSE

To investigate the improvement of image quality and visualization of fibula-free flap (FFF) perforators on computed tomography angiography (CTA) after administration of sublingual nitroglycerin (NTG) tablets.

METHODS

A total of 60 patients with oral or maxillofacial lesions before CTA of the lower extremity were randomly divided into two groups (NTG group and non-NTG group). The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR), overall image quality and grading of vessels were evaluated and compared. The lumen diameters of the major arteries and the proximal and distal peroneal perforators were measured. The number of visible perforators in muscular clearance and muscular layer was also counted and compared between the two groups.

RESULTS

The CNR of posterior tibial artery and overall image quality of CTA images in the NTG group was significantly higher than that in the non-NTG group (p < 0.05), although the SNR and CNR of other arteries did not show significant differences (p > 0.05). The lumen diameters of the peroneal artery and its perforators, anterior tibial artery, and posterior tibial artery were significantly larger in the NTG group (p < 0.001), while no significant difference prevailed in the diameter of the popliteal artery between the two groups (p = 0.298). Compared with the non-NTG group, a significant increase in the number of visible perforators was noted in the NTG group (p < 0.001).

CONCLUSIONS

The administration of sublingual NTG in CTA of the lower extremity can improve the image quality and visualization of perforators, which aids to surgeons select the optimum FFF.

Rates of osteoradionecrosis in resected oral cavity cancer reconstructed with free tissue transfer in the intensity-modulated radiotherapy era

BACKGROUND

Resected oral cavity carcinoma defects are often reconstructed with osteocutaneous or soft-tissue free flaps, but risk of osteoradionecrosis (ORN) is unknown.

METHODS

This retrospective study included oral cavity carcinoma treated with free-tissue reconstruction and postoperative IMRT between 2000 and 2019. Risk-regression assessed risk factors for grade ≥2 ORN.

RESULTS

One hundred fifty-five patients (51% male, 28% current smokers, mean age 62 ± 11 years) were included. Median follow-up was 32.6 months (range, 1.0-190.6). Thirty-eight (25%) patients had fibular free flap for mandibular reconstruction, whereas 117 (76%) had soft-tissue reconstruction. Grade ≥2 ORN occurred in 14 (9.0%) patients, at a median 9.8 months (range, 2.4-61.5) after IMRT. Post-radiation teeth extraction was significantly associated with ORN. One-year and 10-year ORN rates were 5.2% and 10%, respectively.

CONCLUSIONS

ORN risk was comparable between osteocutaneous and soft-tissue reconstruction for resected oral cavity carcinoma. Osteocutaneous flaps can be safely performed with no excess concern for mandibular ORN.

Uncovering the unique characteristics of the mandible to improve clinical approaches to mandibular regeneration

The mandible (lower jaw) bone is aesthetically responsible for shaping the lower face, physiologically in charge of the masticatory movements, and phonetically accountable for the articulation of different phonemes. Thus, pathologies that result in great damage to the mandible severely impact the lives of patients. Mandibular reconstruction techniques are mainly based on the use of flaps, most notably free vascularized fibula flaps. However, the mandible is a craniofacial bone with unique characteristics. Its morphogenesis, morphology, physiology, biomechanics, genetic profile, and osteoimmune environment are different from any other non-craniofacial bone. This fact is especially important to consider during mandibular reconstruction, as all these differences result in unique clinical traits of the mandible that can impact the results of jaw reconstructions. Furthermore, overall changes in the mandible and the flap post-reconstruction may be dissimilar, and the replacement process of the bone graft tissue during healing can take years, which in some cases can result in postsurgical complications. Therefore, the present review highlights the uniqueness of the jaw and how this factor can influence the outcome of its reconstruction while using an exemplary clinical case of pseudoarthrosis in a free vascularized fibula flap.

An Analysis of Volume, Length and Segmentation of Free Fibula Flap in Reconstruction of the Jaws: Investigation of Their Role on Flap Failure

Reconstruction of defects of the jaws is mainly performed via free fibula flap. An incidence of 2–21% of overall flap failure is still described. We investigated the roles of volume, length and number of fibula flap segments on flap survival using novel three-dimensional segmentation tools. We also analyzed the role of other possible risk factors. Seventy-one consecutive patients with a follow up of at least three months and who underwent free fibula flap reconstruction in a single center between 2002 and 2022 have been evaluated. A total of 166 fibula segments were analyzed. Malignancies were the main reason of resection (45.1%). In 69% of the cases a reconstruction of the mandible was performed. The flaps were mainly divided in two segments (39%) (range 1–4), with a mean length of 2.52 cm and a mean volume was 3.37 cm3. Total flap failure (TFF) occurred in 12 cases, (16.9%), while partial flap failure (PFF) appeared in 3 patients (4.2%). Volume, length and number of fibula flap segments did not seem to influence flap failure incidence in uni- and multivariate analysis. Reconstruction of the maxilla and use of a recipient vessel different from the facial artery seemed to significantly impact on flap failure. Smoking and previous surgeries showed a higher trend to flap failure, but they did not reach statistical significance. Prospective and multicentric analysis on a wider population should be assessed.

Osseous Union after Jaw Reconstruction with Fibula-Free Flap: Conventional vs. CAD/CAM Patient-Specific Implants

This is a monocentric, retrospective study of patients who underwent successful immediate or delayed maxilla or mandible reconstructions with FFF from January 2005 to December 2021. Panoramic radiograph, computed tomography scans, and cone-beam CTs were analyzed concerning the osseous union of the intersegmental junctions between maxillary or mandibular native jaw and fibular bone. The primary parameter was to estimate the status of osseous union according to osteosynthesis type. A total number of 133 patients (PSI: n = 64, non-PSI: n = 69) were included in the present study. The mean age was 56.7 ± 14.0 (Range: 14.7−82.7); the primary diagnosis was in 105 patients a malignant (78.9%) and in 20 patients a benign (15.0%) tumor. Mandible reconstruction was performed on 103 patients (77.4%), and on 30 patients (22.6%), maxilla reconstruction was performed. The radiographic images provided a rate of incomplete osseous union (IOU) of about 90% in both groups in the first 6 months. Imaging between 6 and 12 months reveals an IOU rate in the non-PSI group of 46.3% vs. 52.5% in the PSI group, between 12 and 24 months, an IOU rate of 19.6% vs. 26.1%, between 24 and 36 months 8.9% vs. 21.7%, and after 36 months the IOU rate decreases to 4.2% vs. 18.2%. Multivariate logistic regression shows that only osteosynthesis type (OR = 3.518 [95%-CI = 1.223−10.124], p = 0.02) and adjuvant radiotherapy (OR = 4.804 [95%-CI = 1.602−14.409], p = 0.005) are independent risk factors for incomplete osseous union. Cox regression revealed that the variables plate-system (Hazard ratio, HR = 5.014; 95 %-CI: 1.826−3.769; p = 0.002) and adjuvant radiotherapy (HR = 5.710; 95 %-CI: 2.066−15.787; p < 0.001) are predictors for incomplete osseous union. In our study, the rate of incomplete bony fusion was significantly higher in the PSI group. Jaw-to-fibula apposition zones were significantly more affected than intersegmental zones. In multivariate analysis, a combination of osteosynthesis with PSI and adjuvant radiotherapy could be identified as a risk constellation for incomplete ossification.

Infusion management associated with prolonged length of stay following free flap reconstruction of head and neck defects: A propensity score matching study

BACKGROUND

Surgical resection of the primary lesion and reconstruction of the defects with free flaps are common treatments for head and neck cancer (HNC). However, various variables can lead to prolonged length of stay (LOS). The aim of this study is to investigate risk factors correlated with prolonged LOS following free flap reconstruction of head and neck defects.

METHODS

A retrospective study of patients with all types of free flaps reconstruction of HNC between January 2011 and January 2019 at Sun Yat-sen Memorial Hospital was performed. We recorded predictive variables and divided them into: personal and clinical, hemodynamic, anesthetic and surgical. The primary endpoint was prolonged length of stay. Univariate and multivariate analyses were applied to identify risk factors that associated with prolonged LOS. Propensity score matching was performed with the identified risk variables and other perioperative factors that may impact transfusion decision to explore the independent influence of intraoperative blood transfusion on prolonged LOS.

RESULTS

A total of 1047 patients were included in this study. The median LOS was 13.00 (11.00, 16.00) days. Multivariate analysis suggested that blood transfusion, duration of surgery, postoperative complications and unplanned reoperation were associated with prolonged LOS. After propensity score matching, unnecessary blood transfusion and inadequate fluid rate over 24 h, postoperative complications and unplanned reoperation were identified risk factors that led to prolonged LOS.

CONCLUSION

Unnecessary blood transfusion and inadequate fluid infusion rate over 24 h were independent risk factors associated with prolonged LOS in HNC patients who underwent free flap reconstruction. Our results indicated consideration of restrictive blood transfusion and adequate fluid infusion over postoperative 24 h in these patients.

The state of virtual surgical planning in maxillary Reconstruction: A systematic review

Virtual surgical planning (VSP) and computer aided design utilization in head and neck reconstruction has become increasingly popular within the discipline. Advocates of the technology over traditional free hand surgery cite benefits including improved intraoperative efficiencies and postoperative outcomes that have been demonstrated during mandibular reconstruction. More recently, VSP for maxillary and mid facial reconstruction, generally considered more complex than their mandibular counterparts, have been applied with the hopes of similar benefits. However, our literature search revealed no large-scale randomized control trial substantiating these benefits. As such, the aim of this review was to synthesize the existing research on utilization of VSP in the context of maxillary reconstruction. Three databases were systematically searched for articles pertaining to maxillary reconstruction for oncologic, traumatic, or osteoradionecrosis indications. Four hundred and fourteen unique articles were reviewed by two independent reviewers ultimately revealing sixteen studies appropriate for qualitative synthesis including 142 patients. Results of our studies reveal the extreme heterogenicity of application of this technology under the label of virtual surgical planning. Outcome reporting methods were grossly inconsistent amongst all the articles resulting in inability to appropriately synthesize data quantitatively for a meta-analysis. Overall, there was no standard of reporting outcomes of maxillary reconstruction, and no randomized trials comparing virtual surgical planning versus freehand surgery and therefore there is insufficient data to objectively prove purported benefits. To facilitate future comparative studies, a minimal standard of reporting for maxillary VSP is presented and the need for a randomized control trial is highlighted.

Plasmid encoding miRNA-200c delivered by CaCO3-based nanoparticles enhances rat alveolar bone formation

Aim: miRNAs have been shown to improve the restoration of craniofacial bone defects. This work aimed to enhance transfection efficiency and miR-200c-induced bone formation in alveolar bone defects via plasmid DNA encoding miR-200c delivery from CaCO₃ nanoparticles. Materials & methods: The CaCO₃/miR-200c delivery system was evaluated in vitro (microscopy, transfection efficiency, biocompatibility) and miR-200c-induced in vivo alveolar bone formation was assessed via micro-computed tomography and histology. Results: CaCO₃ nanoparticles significantly enhanced the transfection of plasmid DNA encoding miR-200c without inflammatory effects and sustained miR-200c expression. CaCO₃/miR-200c treatment in vivo significantly increased bone formation in rat alveolar bone defects. Conclusion: CaCO₃ nanoparticles enhance miR-200c delivery to accelerate alveolar bone formation, thereby demonstrating the application of CaCO₃/miR-200c to craniofacial bone defects.

Osseous Union after Mandible Reconstruction with Fibula Free Flap Using Manually Bent Plates vs. Patient-Specific Implants: A Retrospective Analysis of 89 Patients

The aim of this monocentric, retrospective clinical study was to evaluate the status of osseous union in uni- and poly-segmental mandible reconstructions regarding conventional angle-stable manually bent osteosynthesis plates (Unilock 2.0 mm) versus titan laser-melted PSI patient-specific implant’s (PSI). The clinical impact of PSI’s high stiffness fixation methods on bone healing and regeneration is still not well addressed. The special interest was in evaluating the ossification of junctions between mandible and fibula and between osteotomized fibula free flap (FFF) segments. Panoramic radiograph (OPT), computed tomography (CT) scans, or cone-beam CTs (CBCT) of patients who underwent successful FFF for mandible reconstruction from January 2005 to December 2020 were analyzed. A total number of 89 cases (28 females (31.5%), 61 males (68.5%), mean age 58.2 ± 11.3 years, range: 22.8–82.7 years) fulfilled the chosen inclusion criteria for analysis (conventional: n = 44 vs. PSI: n = 45). The present study found an overall incomplete ossification (IOU) rate of 24.7% (conventional: 13.6% vs. PSI: 35.6%; p = 0.017) for mandible to fibula and intersegmental junctions. Between osteotomized FFF segments, an IOU rate of 16% was found in the PSI-group, while no IOU was recorded in the conventional group (p = 0.015). Significant differences were registered for IOU rates in poly-segmental (p = 0.041), and lateral (p = 0.016) mandibular reconstructions when PSI was used. Multivariate logistic regression analysis identified plate exposure and type of plate used as independent risk factors for IOU. Previous or adjuvant radiotherapy did not impact incomplete osseous union in the evaluated study sample. PSI is more rigid than bent mini-plates and shields functional mechanical stimuli, and is the main reason for increasing the rate of incomplete ossification. To enhance the functional stimulus for ossification it has to be discussed if patient-specific implants can be designed to be thinner, and should be divided into segmental plates. This directs chewing forces through the bone and improves physiological bone remodeling.

Near-Infrared Fluorescence with Indocyanine Green to Assess Bone Perfusion: A Systematic Review

Background: Adequate perfusion of a bone flap is essential for successful reconstruction of osseous defects. Unfortunately, complications related to inadequate bone perfusion are common. Near-infrared fluorescence (NIRF) imaging enables intraoperative visualization of perfusion. NIRF has been investigated in reconstructive surgery to aid the surgeon in clinical perioperative assessment of soft tissue perfusion. However, little is known on the beneficial use of NIRF to assess bone perfusion. Therefore, the aim of this review was to search for studies evaluating NIRF to assess bone perfusion. Methods: A systematic review, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline, was performed. Studies up to October 2021 were included. We extracted data regarding the study population, size and design, reported objective fluorescence parameters and the methodology used for fluorescence imaging and processing. Results: Ten articles were included. Studies reported unevenly on the protocol used for NIRF imaging. Five studies reported objective parameters. Absolute and relative perfusion parameters and parameters derived from maximum fluorescence were reported. The clinical significance of these parameters has not been evaluated in humans. Conclusion: The evidence on bone perfusion as measured with NIRF is limited. More clinical studies are required.

Impact of Periosteal Branches and Septo-Cutaneous Perforators on Free Fibula Flap Outcome: A Retrospective Analysis of Computed Tomography Angiography Scans in Virtual Surgical Planning

BACKGROUND

Virtual surgical planning (VSP) for jaw reconstruction with free fibula flap (FFF) became a routine procedure and requires computed tomography angiography (CTA) for preoperative evaluation of the lower limbs vascular system and the bone. The aim of the study was to assess whether the distribution and density of periosteal branches (PB) and septo-cutaneous perforators (SCP) of the fibular artery have an impact on flap success.

METHOD

This retrospective clinical study assessed preoperative CTA of the infra-popliteal vasculature and the small vessel system of 72 patients who underwent FFF surgery. Surgical outcome of flap transfer includes wound healing, subtotal, and total flap loss were matched with the segmental vascular supply.

RESULT

A total of 72 patients (28 females, 38.9 %; 44 males, 61.1 %) fulfilled the study inclusion criteria. The mean age was 58.5 (± 15.3 years). Stenoses of the lower limbs' vessel (n = 14) were mostly detected in the fibular artery (n = 11). Flap success was recorded in n = 59 (82.0%), partial flap failure in n = 4 (5.5%) and total flap loss in n = 9 (12.5%). The study found a mean number (± SD) of 2.53 ± 1.60 PBs and 1.39 ± 1.03 SCPs of the FA at the donor-site. The proximal FFF segment of poly-segmental jaw reconstruction showed a higher rate of PB per flap segment than in the distal segments. Based on the total number of prepared segments (n = 121), 46.7% (n = 7) of mono-, 40.4% (n = 21) of bi-, and 31.5 % (n = 17) of tri-segmental fibula flaps were at least supplied by one PB in the success group. Overall, this corresponds to 37.2% (45 out of 121) of all successful FFF. For total flap loss (n = 14), a relative number of 42.9% (n = 6) of distinct supplied segments was recorded. Wound healing disorder of the donor site was not statistically significant influenced by the detected rate of SCP.

CONCLUSION

In general, a correlation between higher rates of PB and SCP and the flap success could not be statistically proved by the study sample. We conclude, that preoperative PB and SCP mapping based on routine CTA imaging is not suitable for prediction of flap outcome.