Latissimus dorsi rotational flap combined with a custom-made scapular prosthesis after oncological surgical resection: a report of two patients

Guidance for Circumflex Scapular Artery Flap Utilization in Pediatric Reconstruction

BACKGROUND

The circumflex scapular artery (CSA) flap system, consisting of scapular, parascapular, and chimeric flaps, is useful for pediatric reconstruction in many anatomical locations. The objectives of this case series are to offer insights into our decision-making process for selecting the CSA flap in particular pediatric reconstructive cases and to establish a framework for choosing a scapular or parascapular skin paddle. We also aim to emphasize important technical considerations of CSA flap utilization in pediatric patients.

METHODS

Pediatric reconstruction with CSA flaps performed at our institution between 2006-2022 was retrospectively reviewed. Patient demographics, indications, flap characteristics, complications, and operative data were abstracted. Functional donor site morbidity was assessed through postoperative physical examinations. Unpaired t test analyzed scapular versus parascapular flap size.

RESULTS

Eleven CSA flaps were successfully performed in 10 patients (6 scapular and 5 parascapular flaps). Patient ages ranged from 2 to 17 years. Scapular fasciocutaneous free flaps (n = 4) were performed in patients' ages 2-5 years for hand and forearm scar contractures. Two pedicled scapular flaps were performed for a single patient for bilateral axillary hidradenitis suppurativa. The 5 parascapular flaps were performed in patients' ages 2-14 years for calcaneus and forearm avulsion wounds and reconstruction after resection of hidradenitis suppurativa, nevus sebaceous, and Ewing sarcoma. In the sarcoma resection case, a chimeric flap with latissimus dorsi was employed. Average flap size was 101.6 ± 87.3 cm 2 (range: 18-300 cm 2 ). Parascapular flaps were significantly larger than scapular flaps (156.60 ± 105.84 cm 2 vs 55.83 ± 26.97 cm 2 , P = 0.0495). Overall, 3 complications occurred (27.3% of cases) including venous congestion (n = 2) and wound dehiscence (n = 1). There were no reported cases of compromised shoulder function at 1.9 ± 2.5-year follow-up. The successful reconstruction rate for scapular, parascapular, and chimeric flaps was 100%.

CONCLUSIONS

The CSA flap treated a wide variety of indications demonstrating the flap's attributes: large vessel caliber, wide arc of rotation, reliable vascular anatomy, minimal donor site morbidity, and ability to incorporate bone and muscle. Our cases also highlight important pediatric considerations such as vascular mismatch and limited scapular bone stock. We recommend selection of the parascapular over the scapular flap with reconstruction of larger, complex defects given its ability to be harvested with a large skin paddle.

Is polypropylene mesh reconstruction functionally superior to non reconstructive group following total scapular resection? A retrospective analysis of 16 patients and a systematic review of the literature

Background

Various reconstruction methods have been described in medical literature on scapular tumor resection depending on the type of resection and other factors. However the ideal method of reconstructions has been still debatable. The purpose of the current study was to assess whether polypropylene mesh reconstruction is superior as compared to non reconstructive group following total scapular resection.We also evaluated how our method of reconstruction fare as compared to reported reconstruction methods in the published literature.

Methods

During 2014 to 2019; Total scapulectomy (Type III scapular resection) was performed in 16 patients for malignant tumor involving scapula bone. Reconstruction with polyprolene mesh(Group I) was performed in 56 % patient and non reconstruction technique (Group II) was observed in 44 % patient. The mean follow-up duration of current study was 28.3 months (range 13-67 months). The search method of PubMed and Cochrane databases provided 121 articles; of which 5 studies having 144 cases were utilised for final analysis. The reconstruction method used were dynamic humeral suspension (39.5%), non reconstruction method (35 %), scapular prosthesis (18 %) and static humeral suspension (5.5%).

Results

The mean Musculoskeletal tumor society score (MSTS) of the study cohort was 19.8(0-23); and that in polyprolene mesh or static suspension method (Group I) and non reconstructive technique (Group II) was 67 % and 61% respectively. The emotional acceptance score in group I was 4.5 and that in group II was 4.2 points. There was no difference in the shoulder movements in both the groups. The mean surgical durations in group I and group II was was 186 min and 140 min respectively. The systematic review showed the mean Musculoskeletal tumor society score (MSTS) of dynamic suspension and non reconstruction method were 63 % and 63.5% respectively. The mean Musculoskeletal tumor society score (MSTS) of scapula prosthesis tended to be higher than those with dynamic suspension (77 % vs 65 %).

Conclusions

The reconstruction with polypropylene mesh had better functional outcome and emotional acceptance as compared to non-reconstructive group in patients with total scapular resection surgery. The findings of systematic review suggest that; patients treated by reconstruction with polypropylene mesh and non-reconstructive group as compared to scapular prosthesis had limited shoulder movements with no difference in hand position, manual dexterity and lifting ability.

Development and validation of 3-dimensional simulators for penile prosthesis surgery

BACKGROUND

The acquisition of skills in penile prosthesis surgery has many limitations mainly due to the absence of simulators and models for training. Three-dimensional (3D) printed models can be utilized for surgical simulations, as they provide an opportunity to practice before entering the operating room and provide better understanding of the surgical approach.

AIM

This study aimed to evaluate and validate a 3D model of human male genitalia for penile prosthesis surgery.

METHODS

This study included 3 evaluation and validation stages. The first stage involved verification of the 3D prototype model for anatomic landmarks compared with a cadaveric pelvis. The second stage involved validation of the improved model for anatomic accuracy and teaching purposes with the Rochester evaluation score. The third stage comprised validation of the suitability of the 3D prototype model as a surgical simulator and for skill acquisition. The third stage was performed at 3 centers using a modified version of a pre-existing, validated questionnaire and correlated with the Rochester evaluation score.

OUTCOME

We sought to determine the suitability of 3D model for training in penile prosthesis surgery in comparison with the available cadaveric model.

RESULTS

The evaluation revealed a high Pearson correlation coefficient (0.86) between questions of the Rochester evaluation score and modified validated questionnaire. The 3D model scored 4.33 ± 0.57 (on a Likert scale from 1 to 5) regarding replication of the relevant human anatomy for the penile prosthesis surgery procedure. The 3D model scored 4.33 ± 0.57 (on a Likert scale from 1 to 5) regarding its ability to improve technical skills, teach and practice the procedure, and assess a surgeon's ability. Furthermore, the experts stated that compared with the cadaver, the 3D model presented greater ethical suitability, reduced costs, and easier accessibility.

CLINICAL IMPLICATIONS

A validated 3D model is a suitable alternative for penile prosthesis surgery training.

STRENGTHS AND LIMITATIONS

This is the first validated 3D hydrogel model for penile prosthesis surgery teaching and training that experts consider suitable for skill acquisition. Because specific validated guidelines and questionnaires for the validation and verifications of 3D simulators for penile surgery are not available, a modified questionnaire was used.

CONCLUSION

The current 3D model for penile prosthesis surgery shows promising results regarding anatomic properties and suitability to train surgeons to perform penile implant surgery. The possibility of having an ethical, easy-to-use model with lower costs and limited consequences for the environment is encouraging for further development of the models.

Surgical Outcomes and Complications of Custom-Made Prostheses in Upper Limb Oncological Reconstruction: A Systematic Review

Bone tumors of the upper limb are a common cause of bone pain and pathological fractures in both old and young populations. Surgical reconstruction and limb salvage have become valid options for these patients despite this kind of surgery being challenging due to the need for wide bone resection and the involvement of surrounding soft tissues. Computer-assisted technology helps the surgeon in pre-operative planning and in designing customized implants. The aim of this study was to investigate the surgical outcomes and complications of custom-made prostheses in oncologic reconstruction of the upper limb and if they are reliable options for patients suffering from aggressive tumors. An electronic search on PubMed, Google Scholar, and Web of Knowledge was conducted to identify all available articles on the use of custom-made prostheses in oncological resections of the upper limb. Twenty-one studies were included in the review, comprising a total of 145 patients with a mean age of 33.68 years. The bone involved was the humerus in 93 patients, and the radius was involved in 36 patients. There were only six cases involving proximal ulna, three cases involving the scapula, and seven cases involving the elbow as well as soft tissues around it. The most frequent primary tumor was the giant cell tumor, with 36 cases, followed by osteosarcoma with 25 cases, Ewing Sarcoma with 17 cases, and Chondrosarcoma with 7 total cases. Forty patients were affected by bone metastases (such as renal cell cancer, breast cancer, melanoma, and rectal cancer) or hematologic diseases involving bone (lymphoma, myeloma, or non-Hodgkin disease). Custom-made prostheses are a viable option for patients who suffer from malignant tumors in their upper limbs. They are a reliable aid for surgeons in cases of extensive resections.

Reverse Turnover Pedicled Latissimus Dorsi Muscle Flap for the Repair of Radiation Ulcer in the Back: A Case Report

Cases of radioactive back ulcers caused by radiation therapy have not been reported. This paper reports a matter of a 55-year-old male patient suffering from chronic back radiation ulcer after coronary stent implantation. Through the repeated and complete expansion of the rear radiation ulcer wound, the back radiation ulcer wound was successfully repaired with the reverse turnover pedicled latissimus dorsi muscle flap, and the clinical effect was satisfactory.

Biological Prosthesis (Hollow 3D-Printed Titanium Custom-Made Prosthesis and Bone Graft) for Humeral Reconstruction in Pediatric Oncologic Patients: Surgical Indications and Results

This study presents the mid-term outcomes of a novel "biological prosthesis" for pediatric humerus reconstruction after major bone tumor removal. This approach involves a hollow 3D-printed titanium custom-made prosthesis combined with bone grafting. The primary aim was to preserve and revitalize the unaffected autologous proximal or distal humeral stump. Between 2017 and 2021, we treated five pediatric patients (mean age 11.2 years; range 7-17) with humeral bone sarcomas. A one-stage surgical procedure involved tumor resection and implanting a hollow 3D-printed custom-made prosthesis. In two cases, we preserved the proximal humerus; in two, the distal part; and in one, both. Graft materials included homologous bone chips in three cases and free vascularized fibular grafts in two cases. All patients were clinically and radiographically assessed after a mean follow-up of 32.2 months (range of 14-68). No significant complications were observed, and no implant revisions were needed. Osseointegration was evident in all cases within eight months post-surgery; vascular support for the remaining autologous stump was demonstrated in all cases. Our hollow 3D-printed custom-made prosthesis and bone grafting offer the potential for partial or complete articular surface preservation. This approach encourages revascularization of the epiphysis, leading to satisfactory outcomes in humerus reconstruction within the pediatric population.

An overview of 3D printed metal implants in orthopedic applications: Present and future perspectives

With the ability to produce components with complex and precise structures, additive manufacturing or 3D printing techniques are now widely applied in both industry and consumer markets. The emergence of tissue engineering has facilitated the application of 3D printing in the field of biomedical implants. 3D printed implants with proper structural design can not only eliminate the stress shielding effect but also improve in vivo biocompatibility and functionality. By combining medical images derived from technologies such as X-ray scanning, CT, MRI, or ultrasonic scanning, 3D printing can be used to create patient-specific implants with almost the same anatomical structures as the injured tissues. Numerous clinical trials have already been conducted with customized implants. However, the limited availability of raw materials for printing and a lack of guidance from related regulations or laws may impede the development of 3D printing in medical implants. This review provides information on the current state of 3D printing techniques in orthopedic implant applications. The current challenges and future perspectives are also included.

Functional Muscle Transfer after Oncologic Extremity Resection

BACKGROUND

 Functional muscle transfer (FMT) can provide wound closure and restore adequate muscle function for patients with oncologic extremity defects. Herein we describe our institutional experience with FMT after oncological resection and provide a systematic review and meta-analysis of the available literature on this uncommon procedure.

METHODS

 A single-institution retrospective review was performed, including all patients who received FMT after oncological resection from 2005 to 2021. For the systematic review and meta-analysis, PubMed, Cochrane, Medline, and Embase libraries were queried according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines; results were pooled, weighted by study size, and analyzed.

RESULTS

 The meta-analysis consisted of seven studies with 70 patients overall, demonstrating a mean Medical Research Council (MRC) score of 3.78 (95% confidence interval: 2.97-4.56; p < 0.01). The systematic review included 28 studies with 103 patients. Receipt of adjuvant chemotherapy was associated with significantly lower mean MRC score (3.00 ± 1.35 vs. 3.90 ± 1.36; p = 0.019). Seventy-four percent of the patients underwent free FMT, with the most common donor muscle being the latissimus dorsi (55%). The flap loss rate was 0.8%. Neoadjuvant chemotherapy (p = 0.03), radiotherapy (p = 0.05), pedicled FMTs (p = 0.01), and a recipient femoral nerve (p = 0.02) were associated with significantly higher complication rates. The institutional retrospective review identified 13 patients who underwent FMT after oncological resection with a median follow-up time of 21 months (range: 6-74 months). The most common tumor necessitating FMT was undifferentiated pleomorphic sarcoma (77%), and the most common donor muscle was the latissimus dorsi (62%). A high body mass index was associated with prolonged neuromuscular recovery (R = 0.87, p = 0.002).

CONCLUSION

 FMT after oncological resection may contribute to improved extremity function. Careful consideration of risk factors and preoperative planning is imperative for successful FMT outcomes.

Management of Scapular Tumors

Scapular resections are large oncologic undertakings. Due to the soft tissue coverage of the scapula, tumors are often able to be resected with a negative margin. Involvement of the brachial plexus and axillary vessels is rare, allowing for a limb-salvage surgery in most cases. Functional outcomes are based on the magnitude of resection; patients undergoing a partial scapulectomy and those with glenoid preservation demonstrate improved outcomes compared to patients undergoing a total scapulectomy or glenoid resection. Although scapular endoprosthetics are available, there is limited data to support their routine use.

3D-Printed Patient-Specific Casts for the Distal Radius in Children: Outcome and Pre-Market Survey

Background: Orthopaedic and Trauma surgery is expected to undergo profound transformation as a result of the adoption of 3D technology. Among the various applications, patient specific manufacturing of splints and casts would appear to be, particularly in children, an interesting implementation. This study aims to assess the safety of patient specific 3D casts obtained with a newly developed 3D-scanning devise in a small case series. We therefore conducted a clinical outcome and pre-marketing study in 10 consecutive patients with distal radius fractures treated at an Academic Level I Pediatric Trauma Center. After the application of the 3D cast, patients underwent three consecutive evaluations in the following 21 days. The main outcome measurements were: pain, skin lesions and general comfort, and acceptance of the cast. The three domains were measured with the Visual Analogue Scale (VAS), the NPUAP/EPUAP classification and the Positive affect-Negative affect Scale for Children (PANAS-C), the Self-Assessment Manikin (SAM) clinical psychology tests and a Likert-type five item questionnaire, respectively. A final mechanical analysis of the cast was carried out to confirm product integrity. Results: The results obtained were consistently positive in the investigated domains of general comfort, efficacy of contention and mechanical integrity of the 3D-printed cast as well as in the practicability of the supply chain. Conclusions: This study provides Level IV evidence that patient specific 3D printed casts obtained with a specifically designed software were safe in the management of “buckle” fractures of the distal radius in children. These results encourage to extend the technology to the treatment of more demanding fractures.

Custom-made 3D-printed prosthesis and free vascularised fibula for humeral reconstruction after osteosarcoma resection in a 13-year-old patient

Surgical reconstruction after humeral resection represents a challenging issue in orthopaedic oncology. Particularly in paediatric patients, the main concerns are maintaining limb function and reconstruction longevity. We describe a novel strategy of humeral reconstruction based on the use of a three-dimensional-printed custom-made prosthesis in a 13-year-old patient diagnosed with osteosarcoma. The implant was specifically designed to sustain the native head, which was spared, as it was not involved by the neoplastic tissue. The mechanical support the prosthesis provided was associated with the biological stimulus of a free vascularised fibular graft to obtain an anatomic, functional and stable construct. This solution has had good longevity, and after 3 years of follow-up, the patient still shows excellent limb function and personal satisfaction.

Custom-Made 3D-Printed Implants as Novel Approach to Reconstructive Surgery after Oncologic Resection in Pediatric Patients

Recently, custom-made 3D-printed prostheses have been introduced for limb salvage surgery in adult patients, but their use has not been described in pediatric patients. A series of 11 pediatric patients (mean age 10.8 years; range 2-13) with skeletal tumors treated with custom-made implants for the reconstruction of bony defects is described. Patients were followed up every 3 months. Functional results were evaluated by the Musculoskeletal Tumor Society Score (MSTS) for upper and lower limbs. The mean follow-up was 25.7 months (range 14-44). Three patients died after a mean of 19.3 months postoperatively-two because of disease progression and the other from a previous malignancy. Three patients experienced complications related to soft tissues. One patient required device removal, debridement, and antibiotic pearls for postoperative infection. Partial osseointegration between grafts and host bone was observed within a mean of 4 months. At the final follow-up, mean MSTS score was 75%. 3D prostheses may yield biological advantages due to possible integration with the host bone and also through the use of vascularized flaps. Further research is warranted.

A hollow, custom-made prosthesis combined with a vascularized flap and bone graft for skeletal reconstruction after bone tumour resection

PURPOSE

While limb-sparing surgery is now possible for more than 80% of patients with bone tumours, wide resection is often required, necessitating bone reconstruction. This paper aims to present a surgical technique that combines the advantages of a hollow, titanium, custom-made prosthesis and the biological aspects of microsurgical flaps and bone graft.

PATIENTS AND METHODS

From June 2016 to September 2017 at our institution, six consecutive patients with skeletal tumours underwent one-stage reconstructive surgery with concomitant implantation of a 3D-printed prosthesis.

RESULTS

At an average follow-up of 30 months (range: 18-45), no early complications were observed, and no implant removals were needed. One patient experienced a delayed haematogenous deep infection, which healed after surgical debridement. Three patients died of their underlying disease 18, 22, and 23 months after surgery, respectively. All flaps and custom reconstructions were successful, with primary osseointegration at a mean of four months (range: 2-7). Patients' average Musculoskeletal Tumour Society score was 23.2 (range: 18-28).

CONCLUSION

A hollow, custom-made, titanium prosthesis filled with bone graft, used in conjunction with a microsurgical flap, may offer good osseointegration in different anatomic locations among a patient population with a high risk of infection, pseudarthrosis, and long-term mechanical complications. The surgical technique's advantages are preliminarily demonstrated. Further studies with longer follow-up periods and larger sample sizes are required to confirm our findings.

Tension Pneumothorax: Is it Sarcoma or Pazopanib?

Synovial sarcomas are rare malignant tumors that originate from primitive pluripotent mesenchymal stem cells that look similar to the developing synovium, but are histologically unrelated to it. Sarcomas commonly metastasize to the lungs and surrounding pleura, with a documented incidence as high as 85% for pleural-based metastases. The incidence of spontaneous pneumothorax in patients with sarcomas is only 1.9%, with synovial sarcoma being the third most common type of sarcoma associated with pneumothorax. While surgical resection is usually the treatment for localized primary synovial cell sarcoma, metastatic disease requires systemic therapy, mainly chemotherapy. Failure of chemotherapy calls for the use of targeted therapeutic agents such as pazopanib. Pazopanib has been linked to the incidence of spontaneous pneumothorax in previous case studies. However, primary research fails to establish a statistically significant causal association. Research shows that pneumothorax can result from lung metastases independent of therapeutic side effects. We report a case of synovial sarcoma of trapezius origin with secondary lung metastases, and development of pneumothorax after pazopanib treatment. We discuss the incidence of pneumothorax as a medication side effect versus independent effect of natural disease progression, and how this plays role in deciding when to continue using a medication in the face of complications.

An innovative occluder for cardiac defect: 3D printing and a biocompatibility research based on self-developed bioabsorbable material-LA-GA-TMC

This study adopted the latest self-developed bioabsorbable material lactide-glycolide-1,3-trimethylene carbonate (LA-GA-TMC) and applied the three-dimensional (3D) printing technique to manufacture the occluder for cardiac septal defects, so as to realize the individualized treatment of cardiac septal defects. At the same time, its biosafety was evaluated, with an aim to establish foundation for futural large-scale animal experiment and clinical trial. The traditional "one-pot synthesis" was modified, and the "two-step synthesis method" was utilized to synthesize the LA-GA-TMC terpolymer at the lactide: glycolide: trimethylene carbonate ratio of 6:1:1.7. Afterward, the synthesized terpolymer was used as the raw material to fabricate the occluder model via using 3D printing technique. Then, its biocompatibility was comprehensively evaluated through cytocompatibility, blood compatibility, and histocompatibility. The occluder made from LA-GA-TMC 3D printing had favorable ductility and recoverability; besides, it possessed the temperature-control feature, and the relative cell proliferation rates in extract liquids at various concentrations were all >70%, suggesting that it had favorable cytocompatibility. Moreover, hemolytic experiment revealed that its hemolytic rate was <5%, dynamic blood coagulation experiment demonstrated that the sample material moderately activated the blood coagulation, and the above findings suggested that it had good blood compatibility. In addition, implanting experiment in vivo revealed that its histocompatibility was superior to the traditional nitinol and the emerging poly-l-lactic acid. It is completely feasible to manufacture the cardiac septal defects occluder based on the novel absorbable material LA-GA-TMC, which has favorable biocompatibility, through 3D printing technique and it possesses broad prospects in large-scale animal experiment and clinical trial.

Application of a three-dimensional printed segmental scapula prosthesis in the treatment of scapula tumors

Chondrosarcoma is characterized by the presence of histologically aggressive behavior, and commonly involves the scapula. Currently, limb salvage surgery is the recommended surgical treatment. Owing to the irregularity of the tumor, the suitability of an implant after tumor resection is a challenge for surgeons. Three-dimensional (3D) printing technology has the potential to make personalized limb salvage surgery a reality. We report the case of a 53-year-old man who was diagnosed with chondrosarcoma of the scapula. Considering the low-grade malignancy and lack of invasion of the glenoid, we agreed upon segmental scapula replacement as the treatment protocol. Nevertheless, reconstruction of the irregular bony defect remaining after tumor resection can be complicated. Therefore, a personalized prosthesis and navigation template corresponding to tumor was designed with 3D printing technique, and tumor resection, prosthesis implantation, and rotator cuff reconstruction were completed. The affected shoulder achieved satisfactory function during a 32-month follow-up with no tumor recurrence. 3D printing technique can help implement the individualized design of the implant and accurate reconstruction after tumor resection, simplify complicated operations, improve operational efficiency, and allow early functional recovery.

Personalized 3D-printed endoprostheses for limb sparing in dogs: Modeling and in vitro testing

Osteosarcoma is the most common type of bone cancer in dogs, treatable by amputation or limb-sparing surgery. For the latter, commercially available plate - endoprosthesis assemblies require contouring, to be adapted to the patient's bone geometry, and lead to sub-optimal results. The use of additively-manufactured personalized endoprostheses and cutting guides for distal radius limb-sparing surgery in dogs presents a promising alternative. Specialized software is used for the bone structure reconstruction from the patient's CT scans and for the design of endoprostheses and cutting guides. The prostheses are manufactured from a titanium alloy using a laser powder bed fusion system, while the cutting guides are manufactured from an ABS plastic using a fused deposition modeling system. A finite element model of an instrumented limb was developed and validated using experimental testing of a cadaveric limb implanted with a personalized endoprosthesis. Personalized endoprostheses and cutting guides can reduce limb sparing surgery time by 25-50% and may reduce the risk of implant failure. The numerical model was validated using the kinematics and force-displacement diagrams of the implant-limb construct. The model indicated that a modulus of elasticity of an implant material ranging from 25 to 50 GPa would improve the stress distribution within the implant. The results of the current study will allow optimization of the design of the personal implants in both veterinary and human patients.

Methods for verification of 3D printed anatomic model accuracy using cardiac models as an example

Background

Medical 3D printing has brought the manufacturing world closer to the patient’s bedside than ever before. This requires hospitals and their personnel to update their quality assurance program to more appropriately accommodate the 3D printing fabrication process and the challenges that come along with it.

Results

In this paper, we explored different methods for verifying the accuracy of a 3D printed anatomical model. Methods included physical measurements, digital photographic measurements, surface scanning, photogrammetry, and computed tomography (CT) scans. The details of each verification method, as well as their benefits and challenges, are discussed.

Conclusion

There are multiple methods for model verification, each with benefits and drawbacks. The choice of which method to adopt into a quality assurance program is multifactorial and will depend on the type of 3D printed models being created, the training of personnel, and what resources are available within a 3D printed laboratory.