Vascularized Bone Graft Research Articles

Patient outcome scores between 1,2- and 2,3-intercompartmental supra-retinacular artery (ICSRA) pedicled vascularised bone grafts (PVBGs) in the treatment of proximal pole scaphoid fracture non-union – a questionnaire study

BackgroundNumerous studies have been published on the use of 1,2-intercompartmental supra-retinacular artery (ICSRA) as a pedicled vascularised bone graft (PVBG) in scaphoid fracture non-union, however, only very few studies have reported their results of 2,3-ICSRA. The aim of this study was to compare the patient-rated outcome scores between these two PVBGs in proximal pole scaphoid fracture non-union.MethodsNineteen patients who underwent surgery for scaphoid non-union between 2017 and 2021 at a single institution were recruited retrospectively in this study. All patients were operated by a one senior orthopaedic surgeon. A mailed questionnaire with the modified mayo wrist (MMW) and the patient rated wrist evaluation (PRWE) scores were sent to the patients.ResultsAll patients were males with a mean age of 22.5 years. There was no statistically significant difference in the PRWE score between the two PVBGs. However, a statistically significant difference was found in the MMW score, with the 1,2-ICSRA PVBG having better scores.ConclusionDespite the 2,3-ICSRA having a longer arc of rotation, longer nutrient arteries, and is technically easier to incorporate in a PVBG, when compared with the 1,2-ICSRA it did not result in better patient-rated outcome scores.

Spino-plastic surgery: A literature review of vascularized bone grafts and their uses in spine reconstruction

The role of plastic surgeons in the world of spine surgery is quickly evolving. The plastic surgeon now serves both a therapeutic and prophylactic role in addressing complications of complex and revision spine surgery. The field of Spino-plastic Surgery is characterized by the use of vascularized bone grafts (VBGs). VBGs are bone segments transferred on their corresponding muscular attachments without the inclusion of a named vessel. The bone graft is adequately vascularized through the connection of the tendon by Sharpey's fibers and their associated microvasculature. VBGs provide an autologous, pedicled tissue rearrangement option with osteoinductive properties and adequate structural support for complex spine reconstruction. VBGs are associated with a lower risk of adverse events and shorter times to fusion than allografts, and bypass the need for lengthy microsurgical anastomosis. Five types of VBGs for spine reconstruction are described in this article, including iliac crest, rib, occiput, scapula, and spinous process VBG. Virtually any vertebral level can be reached for arthrodesis using one or more of these VBGs.

Usefulness of the lateral arm free flap for hand defect reconstruction

Purpose: Although various surgical reconstruction methods are available for multidigit defects or soft tissue defects of the hand, they often require a thin flap due to the hand’s unique physical characteristics. We performed a total of 13 cases of lateral arm free flap surgery at our hospital. The purpose of this study was to report the usefulness of this technique. Methods: This study included the following cases: four cases of multiple digit amputations, seven cases of hand dorsum skin defects, one case of first web reconstruction due to web contracture, and one case of an index finger bone and soft tissue defect with only the ulnar-side neuro-vascular bundle remaining. After emergency simple debridement, subsequent reconstruction was performed using a lateral arm free flap. Results: All 13 cases healed without necrosis. Patients who underwent finger amputation were able to preserve the length of their fingers without any additional amputation. Patients who initially had hand dorsum defects were able to maintain grasping function after flap stabilization. The patient with web contracture was able to recover the lost pinching function, and the patient with a combined loss of osteoarticular and soft tissue of the index finger maintained the shape and length of the finger despite the absence of joint function. Conclusion: The lateral arm free flap is a useful reconstruction method that can be easily performed with a single session of regional anesthesia. Since the flap is thin, it is suitable for hand defect reconstruction. If necessary, vascularized bone grafting is possible.

The Reconstruction of Mandible Defects in War Injuries: Systematic Review and Meta-Analysis.

Systematic Review and Meta-Analysis. There has been an increasing trend in maxillofacial injuries associated with combat trauma. Within the maxillofacial complex, the mandible is the most likely structure to be damaged during combat. The structural deficits as a result can be reconstructed with many options. These include vascularised bone grafts (VBGs), non-vascularised bone grafts (NVBGs), alloplastic implants, reconstruction bars and distraction osteogenesis. This study aimed to determine the common modality and efficacy of mandibular reconstruction in combat trauma-related defects. A literature search was conducted on Pubmed, Prospero, Dynamed, DARE, EMBASE, COCHRANE and BMJ databases. A total of six articles met the inclusion criteria identifying 165 patients requiring mandibular reconstruction. Non-vascularised iliac bone graft (n = 137) was the most common method followed by ileac crest bone chips harvest using Dacron urethran osteomesh tray (n = 24) and frontoparietal grafts (n = 4). Meta-analysis of five out of six trials demonstrated an overall success rate of 85% (95% CI 79-90; I2 = 59%). A total of 13% (n = 22) of reconstructions failed either completely or partially and 21% (n = 34) of patients suffered postoperative complications. NVBGs are a practical, cost-effective and favourable method of war zone management of mandibular defects with success rates comparable to those reported in the civilian literature. However, general trauma principles take precedence to rule out life-threatening injuries. Due consideration of patient factors, surgical factors, and available resources are required in the first-line management of combat-related mandibular defects.

Vascularized Bone Grafting Versus the 2-Stage Masquelet Technique for Upper-Extremity Bone Reconstruction: A Meta-Analysis

Vascularized bone grafting (VBG) has been described as the technique of choice for larger bone defects in bone reconstruction, yielding excellent results at the traditional threshold of 6 cm as described in the literature. However, we hypothesize that the 2-stage Masquelet technique provides equivalent union rates for upper-extremity bone defects regardless of size, while having no increase in the rate of patient complications. A systematic literature review was conducted using PubMed and Scopus for outcomes after VBG and the Masquelet technique for upper-extremity bone defects of the humerus, radius, ulna, metacarpal, or phalanx (carpal defects were excluded). A meta-analysis was performed to compare outcomes following VBG and the Masquelet technique at varying defect sizes. There were 77 VBG (295 patients) and 25 Masquelet (119 patients) studies that met inclusion criteria. Patients undergoing the Masquelet technique had defect sizes ranging from 0-15 cm (average 4.5 cm), while patients undergoing VBG had defect sizes ranging from 0-24 cm (average 5.9 cm). The union rate for Masquelet patients was 94.1% with an average time to union of 5.8 months, compared to 94.9% and 4.4 months, respectively, for VBG patients. We did not identify a defect size threshold at which VBG demonstrated a significantly higher union rate. No statistically significant difference was found in union rates between techniques when using multivariable logistic regression analysis. There was no statistically significant difference in union rates between VBG and the Masquelet technique in upper-extremity bone defects regardless of defect size. Surgeons may consider the Masquelet technique as an alternative to VBG in large bone defects of the upper extremity. Therapeutic IV.

Functional Chimeric Double-barrel Fibula and Reinnervated Peroneus Brevis Osteomyocutaneous Flap for One-stage Forearm Reconstruction.

Reconstructing a mangled limb is complex and requires expertise in both bone and soft-tissue reconstruction, particularly when there is significant muscle loss. Typically, multistage surgery is necessary, starting with soft-tissue coverage, followed by bone grafting and tendon transfers. Sometimes, microsurgical techniques such as vascularized bone grafts and free functional muscle transfers are necessary, especially when there is a bone defect of over 6 cm; the soft-tissue environment is infected, scarred, or poorly vascularized; or there are extensive musculotendinous injuries. We treated a 34-year-old man who had a crushed left forearm resulting in an 18 × 8 cm open wound, 5-cm radius and 7-cm ulna bone defects, loss of the extensor pollicis longus and brevis muscles, and extensive injuries to the other musculotendinous structures of the forearm. To accomplish a one-stage reconstruction, we used a chimeric fibula osteomyocutaneous flap that included a 20 × 10 cm skin flap, peroneus brevis muscle with its motor nerve, and two segments of fibula. The proximal and distal fibula segments were used for ulnar and radial bone reconstruction, respectively, preserving forearm supination and pronation. The peroneus brevis tendon was sutured to the extensor pollicis longus tendon, and its motor nerve was coaptated with the posterior interosseous nerve to restore thumb extension. The skin flap provided complete coverage of all exposed bone and tendon structures. At the 12-month follow-up, the patient regained full extension of the thumb, and there were no difficulties with forearm supination and pronation or with foot eversion and plantar flexion at the donor leg.

Symptomatic Heterotopic Bone Formation after 1,2 ICSRA in Scaphoid Nonunions.

Background We observed several cases of heterotopic bone formation after a 1,2 intercompartmental supraretinacular artery (1,2 ICSRA) distal radius vascularized bone graft (VBG) for the treatment of scaphoid nonunion. This adverse event seems underreported. Knowledge about factors associated with the formation of heterotopic bone after VBGs might help reduce this adverse event. Purpose What factors are associated with resected heterotopic bone formation after 1,2 ICSRA distal radius graft for the treatment of scaphoid nonunion? Patients and Methods We retrospectively reviewed all patients with a scaphoid nonunion treated with a 1,2 ICSRA distal radius graft between 2008 and 2019 in an urban level 1 trauma center in the Netherlands. We included 42 scaphoid nonunions in 41 people treated with the 1,2 ICSRA graft. We assessed potential correlation with patient, fracture, and treatment demographics. Results Heterotopic bone developed in 23 VBGs (55% [23/42]), of which 5 (12% [5/42]) were resected. Heterotopic bone was located radially (at the pedicle side) in all participants. Except a longer follow-up time ( p = 0.028), we found no variables associated with the development of heterotopic bone formation. Conclusion The location of the heterotopic bone at the pedicle site in all cases suggests a potential association with the periosteal strip. Surgeons might consider not to oversize the periosteal strip as a potential method to prevent heterotopic ossification after VBG. Level of Evidence Level II, prognostic study.

A modified induced membrane 2-stage technique using a thoracodorsal artery perforator free flap followed by vascularized or non-vascularized free fibular transfer for the treatment of complex bone infection with concomitant severe soft tissue lesion–A case series of 9 cases

Treatment of post-traumatic complex bone infection is very challenging. The two principal bone reconstruction approaches are the single-stage vascularized bone graft technique and the two-stage induced membrane technique (IMT). Here we introduce a modified 2-stage induced membrane technique (MIMT) for complex long bone infection with a major bone defect and a concomitant severe soft tissue lesion. The 2-stage procedure consists of bone debridement, placement of a PMMA spacer and soft tissue reconstruction with a thoracodorsal artery perforator free flap (“Tdap”) at stage 1. At stage 2, the thoracodorsal artery perforator flap is elevated and a fibular strut graft (either vascularized of non-vascularized) is placed for bone reconstruction.We retrospectively analyzed the extents of lower extremity, long bone, post-traumatic bone infection treated via MIMT from 2008 to 2020. There were nine such cases (eight males) of mean age 59.8 (range 31 to 79) years. The osteomyelitis durations ranged from 3 to 360 months (mean 53 months). The cortical bone defect sizes was ranged from 9 to 14 cm (mean10.7 cm). All skin resurfacing employed Tdap. Vascularized fibular grafts were placed in six patients and non-vascularized grafts were placed in three. The fibular graft size ranged from 12.5 to 19 cm (mean 16.2 cm). Non-vascularized iliac bone grafts served as the fibula docking sites.Unfortunately, all patients suffered complications before bone union was achieved. One case of plate stress fracture and one case of screw fracture required plate and screw change. In three cases of cellulitis, one resolved by use of intravenous antibiotics, others required plate and screw removal. Wound disruption required re-suture and distal skin flap partial necrosis was covered by perforator-based island flap. One case of fibular stress fracture needed cast for 4 weeks. A peroneal nerve palsy patient recovered spontaneously. Bone union was achieved after 6 months in five patients and after 8 months in three (mean 6.9 months). All patients were able to walk unaided. The follow-up period ranged from 2 to 14 years (mean 6.2 years).MIMT saves the limbs in cases with difficult post-traumatic bone infection. It is valid treatment option for complex bone infections with severe soft tissue lesions. However, even with this technique potential complication must be considered.

Is liquid nitrogen recycled bone and vascular fibula combination the biological reconstruction of choice in lower extremity long bone tumor-related defects?

Combination techniques, which encompass the combined use of vascularized bone grafts with massive allografts or autografts (recycled bone grafts), are especially important in the biological reconstruction of tumor-related lower extremity long bone defects. Liquid nitrogen recycled bone (frozen autograft) and free vascular fibula graft (FVFG) combination, which was coined as the "frozen hotdog (FH)" method by the authors, has not been as widely used nor its outcomes reported for significantly sized patient groups. This study aims to provide an answer to whether FH is a safe and effective reconstructive tool for limb salvage in malignant tumors of the lower extremity regarding radiological, functional, and oncological outcomes. Sixty-six (male/female: 33/33) patients, who underwent FH reconstruction for tumor-related massive defects of lower extremity long bones between 2006 and 2020, were retrospectively analyzed. The mean age was 15.8 (3.8-46.7) years. The most common tumor localizations were distal femur (42.4%) and proximal tibia (21.2%) while classic osteosarcoma and Ewing's sarcoma were the most common pathologies (60.6% and 22.7%, respectively). Mean resection and FVFG lengths were 160 (90-320) mm and 192 (125-350) mm, respectively. The mean follow-up was 73.9 (24-192) months. The mean MSTS score was 25.4 (15-30) and the mean ISOLS radiographic score was 22.6 (13-24). Mean time to full weight bearing without any assistive devices was 15.4 (6-40) months and the median time was 12 months. MSTS score negatively correlated with resected segment length and vascular fibula length (p < 0.001; p = 0.006). Although full contact apposition of the FH segment correlated with earlier full weight bearing compared to partial apposition (mean 13.7 vs. 17.9 months) (p = 0.042), the quality of reduction did not affect the ISOLS radiographic score at LFU. Overall limb survival rate was 96.3% at 5 and 10 years while FH survival rate was 91.0% and 88.1% at 5 and 10 years. Local recurrence-free survival rates were 88.8% and 85.9%, and overall survival was 89.9% and 86.1% at 5 and 10 years, respectively. Limb length discrepancy was the most common complication with 34 (51.5%) patients while shell nonunion was seen in 21 (31.8%) patients and graft fracture in 6 (9.1%). The "FH" method is a safe, effective, and extremely cost-efficient reconstructive tool for tumor-related lower extremity long bone defects. Patient compliance to protracted weight-bearing, ensuring the vitality of the FVFG, and achieving an oncologically safe resection are key factors for a successful outcome.

Sexual Dimorphism of the Nutrient Foramen of the Fibula and Its Importance in Vascularised Bone Grafting: A Descriptive Cross-Sectional Study.

Vascularised fibular bone grafting is widely used in many reconstructive surgeries to repair bony defects. It is very essential for the nutrient blood supply to be conserved in the vascular bone graft. Understanding the sexual differences of the fibular nutrient foramen can help operating surgeons make appropriate changes in their clinical methodologies according to the sex. The present study was done to evaluate the sexual dimorphism of fibular nutrient foramen and its clinical importance in the adult central Indian population. This descriptive cross-sectional study was done on 136 dry adult central Indian human fibula bones of known sex (male: 68 and female: 68). The presence of nutrient foramen, their numbers, relation with fibular surfaces, and distance from the styloid process were assessed and were then clinically correlated. In males, single-nutrient foramen and double-nutrient foramina were seen in 92.65% and 7.35% of fibula, respectively. Whereas in females, single-nutrient foramen and double-nutrient foramina were seen in 95.59% and 4.41% of fibula, respectively. The position of the nutrient foramen and the fibular length showed significant sexual variation. This study concludes that among both sexes, the single fibular nutrient foramen in the middle third segment was the most prevalent. Compared to the female population, the male population demonstrated a broader location of the nutrient foramen.

Comparison of the treatment results of humerus diaphysis post-traumatic false joints using vascularized bone grafts with and without a monitor skin flap: Retrospective cohort study

BACKGROUND: The use of the microvascular flap in reconstructive surgery of complicated nonunions of the diaphysis of the humerus is highly valuable. Flaps with compromised blood supply are possible in up to 10% of cases and often lead to the failure of vascularized reconstruction. The combined skin + bone graft is a simple, useful, and reliable option for flap vitality control with a high success rate.&#x0D; OBJECTIVE: To compare microvascular grafting with versus without monitoring the skin flap.&#x0D; MATERIALS AND METHODS: Forty-one microvascular grafting was performed from 2010 to 2017 in patients with humeral non-union and bone defects in the Department of Microsurgery and Trauma of the Hand of Priorov National Medical Research Center of Traumatology and Orthopedics. A combined skin bone flap was used in 23 (56%) patients, and in 18 (44%) patients, grafting was performed without monitoring the skin flap Computed tomography and X-ray imaging were used to monitor non-union healing. The use of a signal skin flap is an effective way to control blood flow in the graft and improves treatment results.&#x0D; RESULTS: In the group without monitoring of the skin flap, non-union healing was documented in 14 (77%) cases. In the group with monitoring of the skin flap, nonunion healing occurred in 22 (96%) cases.&#x0D; CONCLUSION: Monitoring the skin flap is an effective option to ensure microvascular flap blood supply control and improves the outcomes in humeral nonunion healing.

Avascular necrosis of the femoral head: management remains controversial

Management of pre-collapse atraumatic avascular necrosis of the femoral head remains a controversial topic. We conduct this scoping literature review to discuss current perspectives on management. Avascular necrosis of the femoral head (AVNFH) is a progressive pathology of the hip. If left untreated, 80% of cases progress to collapse of the femoral head and require total hip arthroplasty (THA). It is the third commonest reason for THA in the UK (and this proportion is even higher in other parts of the world) and, compared to other indications for THA, affects a disproportionately young population. Successful management demands early diagnosis and interventions to prolong native hip-joint preservation and delay femoral head collapse. Pathophysiology is poorly understood and aetiologies are varied. The ultimate cause of the disease is loss of blood supply to the proximal femur. AVNFH can be traumatic (fracture or dislocation) or atraumatic (80% due to corticosteroid use or alcohol excess). Traumatic causes of AVNFH require accurate and expedient management to prevent AVNFH post-injury. Fixation of fractures requires anatomical reduction to reduce the risk of AVNFH. Dislocation of the proximal femur requires reduction within 12 hours. Hips reduced after this time are much more likely (5.627 odds ratio) to suffer AVNFH. Atraumatic AVNFH can be managed conservatively, pharmacologically or surgically. Surgical interventions such as core decompression or osteotomy have a large body of evidence demonstrating that they can improve symptoms, delay progression and reduce the need for conversion to THA. There are many emerging augmentation procedures, and variations to established procedures, that utilize non-vascularized bone grafts, vascularized bone grafts and bone morphogenetic protein. There is a growing body of evidence to suggest that these augmentations improve outcomes.

Humeral Head Avascular Necrosis

» Avascular necrosis (AVN) of the humeral head is the result of ischemic injury to the epiphyseal bone leading to humeral head collapse and arthritis.» Common causes include trauma, chronic corticosteroid use, or systemic disease processes, such as sickle cell disease, systemic lupus erythematosus, or alcohol abuse.» Nonoperative treatment consists of risk factor management, physical therapy, anti-inflammatory medications, and activity modification.» Surgical treatment options include arthroscopic debridement, core decompression, vascularized bone grafts, and shoulder arthroplasty.

Osteochondral Autograft Transplantation for Proximal Pole Scaphoid Nonunions

Osteochondral autograft transplantation (OAT) is a technique to reconstruct the proximal pole scaphoid nonunion associated with an intact dorsal and volar scapholunate ligament. This study aimed to report the clinical and radiographic outcomes in patients who underwent OAT for this indication. A retrospective review of patients who underwent proximal pole scaphoid nonunion reconstruction with a femoral trochlea OAT was undertaken between 2018 and 2022. Patient demographics, scaphoid nonunion characteristics, surgery details, and clinical and radiographic outcomes were obtained. Eight patients underwent the procedure at an average of 18.2 months from injury. Four patients failed prior attempts at scaphoid union surgery, one of whom failed two prior surgeries. Four had no prior surgery. The average follow-up was 11.8 months. The postoperative wrist flexion-extension arc of motion was 125° or 87% of the contralateral wrist. Grip strength averaged 30.0 kg or 86% of the contralateral side. Adjusted grip strength for hand dominance was 81% of the contralateral side. All OATs healed. Computed tomography scan confirmed the union in 6 patients between 6 and 10 weeks. Two patients whose radiographs demonstrated OAT incorporation at the time of follow-up did not undergo advanced imaging. Osteochondral autograft transplantation is an attractive surgical reconstructive procedure for patients with proximal pole scaphoid nonunions associated with an intact scapholunate ligament. Osteochondral autograft transplantation mitigates the need for vascularized bone grafting, has a rapid time to osseous incorporation, and has a simple postoperative course in which patients can expect early union, near-full range of motion, and grip strength. Therapeutic V.

Awareness and attitude of maxillofacial surgeons in India towards prosthetic rehabilitation after ablative jaw surgery

Purpose: The study investigated the awareness and attitude of maxillofacial surgeons towards prosthetic rehabilitation after ablative jaw surgery. Materials and Methods: A questionnaire-based survey using google forms was designed to assess the awareness and attitude of maxillofacial surgeons. The questionnaire comprising of 23 closed- ended and multiple-choice questions. A total of 150 forms were sent to maxillofacial surgeons through e-mail. Results: Upon analyzing 103 responses it was observed that in the case of maxillectomy defects, the size of the lesion was designated as the most common factor (87%) for deciding between surgical reconstruction or prosthetic rehabilitation. 89% of respondents agreed that presurgical consultation with a maxillofacial prosthodontist could improve the rehabilitation success rate. The most common modality used for the reconstruction of mandibulectomy defects is vascularized bone grafts (32 %), reconstruction plate (30 %), and locoregional flaps for reconstruction by 20% of surgeons. Speech (64.1%) and nasal regurgitation (62%) were the two most important functions that the patient demanded to be corrected after maxillectomy whereas after mandibulectomy masticatory difficulties faced by the patient were the primary reason for seeking the prosthesis as suggested by 84% of respondents. Conclusion: The findings of this study show lack of awareness among surgeons regarding prosthetic rehabilitation of the post jaw resection patients. Ablative tumors of jaws necessitate amultidisciplinary team approach due to their effects on the functional and esthetic aspects of the patients involved. The response also emphasizes the need for a maxillofacial prosthodontist in the complete rehabilitation of the patients. (Int J Maxillofac Prosthetics 2023;6:8-15)

Outcomes Of Reconstruction With Vascularized Vs Non Vascularized Bone Graft After Resection Of Bone Tumours- A Systematic Review And Meta-Analysis.

Vascularized (VBG) and non-vascularized (NVBG) bone grafting are two crucial biological reconstructive techniques in the management of bone tumours. The objective of this study is to compare the outcomes of reconstruction with vascularized and non-vascularized bone grafts after resection of bone tumours. A systematic evaluation of the literature from 2012-2021 was undertaken using the online databases PubMed/Medline, Google Scholar, and Cochrane Library considering only comparative articles with specific outcomes for the restoration of the defect with vascularized and non-vascularized bone graft following the resection of bone tumours. The quality of the research methodology was evaluated using Oxford Quality Scoring System and Newcastle Ottawa Scale for randomized trials and non-randomized comparison research respectively. The SPSS version 23 was used to examine the data that was collected. Musculoskeletal tumour society score (MSTS), bone union time, and complications were the outcomes of this review. Four clinical publications were considered, totalling 178 participants (92 men and 86 women) with 90 patients with VBG and 88 with NVBG. MSTS score and bone union time were the key outcomes that were measured. The overall MSTS (p>0.05) and rate of complications (p>0.05) results were comparable between the two groups, however, VBG had a better rate of bone union (p<0.001). As a result of the quicker bone union, our systematic evaluation demonstrated that VBG causes earlier recovery. Complication rates and functional results were the same in both groups. The link between the bone union time and functional score following VBG and NVBG must also be demonstrated.

Vascularized Bone Grafts from the Lateral Femoral Condyle for the Treatment of Avascular Lunate Necrosis (Kienböck's).

Avascular necrosis of the lunate (Kienböck's disease) is rare and one of the main causes of progressive painful arthritis, requiring surgical intervention. Various approaches have shown benefits in treating Kienbock's disease but with limitations. The article aims to analyze the functional outcome using lateral femoral condyle free vascularized bone grafts (VBGs) as the first choice of treatment for Kienböck`s. This was a retrospective analysis of 31 patients with Kienbock's who had microsurgical revascularization or reconstruction of the lunate between 2016 and 2021 using either corticocancellous or osteochondral VBGs from the lateral femoral condyle. The characteristics of lunate necrosis, choice of VBG and postoperative functional outcome were reviewed. Corticocancellous VBGs were used in 20 patients (64.5%), while osteochondral VBGs in 11 patients (35.4%). The lunate was reconstructed in 11 patients, revascularized in 19 patients, and one patient received augmentation of a luno-capitate arthrodesis with a corticocancellous graft. We noted postoperative irritation of the median nerve (n = 3) and screw loosening requiring removal (n = 1) as minor complications. All patients had complete graft healing at eight-month follow-up and acceptable functional outcomes. Free VBG from the lateral femoral condyle represent a reliable method of lunate revascularisation or reconstruction in advanced Kienböck's. Their main advantages are the constant vascular anatomy, straightforward graft harvesting technique and possibility to harvest several graft types according to the requirements at the donor site. Postoperatively, the patients become pain-free and have an acceptable functional outcome.

Fibula flap in upper extremity segmental/critical size bone defects fixed with locking plates. Single-institution observational cohort

IntroductionManagement of bone defects in the upper extremity can vary depending on the size and location of the defect. Large defects may require complex reconstruction techniques. Vascularized bone grafts, mainly free vascularized fibula flap (FVFF), have many advantages in the treatment of bone or osteocutaneous defects. However, complications such as graft fracture are the most common, with a free fibula flap for bone defects in the upper extremity. This study aimed to describe the results and complications associated with the treatment of posttraumatic bone defects in the upper extremity using FVFF. We hypothesized that performing osteosynthesis using locking plates would prevent or reduce the fracture of the fibula flap Materials and methodsThis was a retrospective single-centre cohort study. Patients with segmental bone defects caused by trauma who underwent reconstructive surgery with FVFF fixed with locking compression plates (LCP) between January 2014 and 2022 were included. Demographic variables and preoperative data, such as bone defect, location, and time until reconstruction, were collected. Bone defects were classified according to the Testworth classification. Intraoperative variables included the length of the FVFF, type of graft (osteocutaneous or not), type and technique of arterial and venous sutures, number of veins used as output flow, and the osteosynthesis technique used. ResultsTen patients were included (six humerus, three ulna, and one radius). All patients had critical-size bone defects, and nine patients had a history of infection. In 9 of 10 patients, bone fixation was performed with a bridge LCP and in one patient with two LCP plates. In eight cases, the FVFF was osteocutaneous. All the patients showed bone healing at the end of the follow-up period. There was one early complication, donor site wound dehiscence, and two long-term complications (proximal radioulnar synostosis and soft-tissue defect). ConclusionA high rate of bone union with a low rate of complications can be obtained with an FVFF in upper extremity segmental/critical-size bone defects. Rigid fixation with locking plates avoids stress fractures of the grafts, mainly in humeral reconstruction. However, in these cases, a bridge plate should be used.

Scaphoid Nonunions Treated with Nonvascularized Bone Grafting and Screw Fixation.

Background Vascularized bone grafting with screw fixation is currently considered the treatment of choice for scaphoid nonunions with avascular necrosis (AVN) of the proximal pole. A viable alternative to using vascularized bone grafts for scaphoid nonunions with AVN is nonvascularized bone grafting with screw fixation. Question What are the functional outcomes of patients with scaphoid nonunions and associated proximal pole AVN who are treated with nonvascularized distal radius bone grafting and screw fixation? Patients and Methods Eight scaphoid nonunions with AVN, which received nonvascularized distal radius bone graft and screw fixation, underwent a retrospective review. Range of motion, strength, and Disabilities of the Arm, Shoulder, and Hand (DASH) scores were obtained. Follow-up X-rays were compared with immediate postoperative X-rays. Results At a mean follow-up of 88.9 months, thumb palmar abduction and radial abduction were significantly higher on the operative side ( p = 0.28 and 0.49, respectively). Extension/flexion arc was significantly lower in the operative wrist ( p = 0.148). There was no significant difference between the operative and nonoperative sides with regard to strength. The median postoperative DASH score was 2.9 (interquartile range [IQR]: 8.3). There was no progression of osteoarthritis when immediate postoperative and follow-up X-rays were compared. Radiographic union was observed in six of the seven (85.7%) patients who were able to return to the office for follow-up radiographs. The mean scapholunate and radioscaphoid angles measured on X-rays were within normal anatomic range postoperatively. Conclusions Using nonvascularized distal radius bone graft and screw fixation in the treatment of scaphoid nonunions with associated AVN has favorable radiologic and functional outcomes and should be considered a viable treatment option for this difficult problem.

INCREASING LOCAL CELL DENSITY BY SOUND TO ENGINEER VASCULARIZED BONE CONSTRUCTS

Successful application of patient derived cells to engineer vascularized bone grafts is often hampered by low cell numbers and lengthy in vitro expansion. With sound induced morphogenesis (SIM), local cell density enhancement was shown to improve microvasculature formation at lower cell concentration than conventional methods [1]. SIM takes advantage of hydrodynamic forces that act on cells to arrange them within a hydrogel. Following, we are evaluating the potential of cell-hydrogel biografts with high local cell density to improve the therapeutic efficacy in clinical scenarios such as anastomosis or bone formation within non-union fractures.To assess anastomosis, human umbilical vein endothelial cells (HUVEC) and human mesenchymal stromal cells (MSC) were mixed at a 1:1 ratio in PEG-based or Dextran-based hydrogels at a final concentration of 2×106 cells×mL-1. For ectopic bone formation, MSC were resuspended in PEG-based hydrogels at 2×106 or 5×106 cells×mL-1, with or without BMP-2. Cells were assembled into distinct patterns at a frequency of 60 Hz. Four biografts of 4 × 9 mm2 were implanted at the back of nude mice (total of 7 animals) and harvested after 2 or 8 weeks. Explants were fixed and imaged as whole constructs or embedded in paraffin for histological analysis.Upon explantation, microscopic evaluation indicated that HUVEC were retained within the PEG-hydrogel after 2 weeks and formed a pre-vascular network. In the second study, ectopic bone formation was more pronounced in areas of higher local cell density based on visual inspection. Ongoing experiments are further characterizing bone formation by micro-CT and histological evaluation.Our results indicate that local cell density enhancement by sound requires a lower initial cell concentration than conventional, static seeding methods to achieve comparable microvasculature structures or local osteogenesis.