Anatomy of the Vascularized Lateral Femoral Condyle Flap:

The Chimeric LFC and DCIA Flap in Combined Mandibular and Condylar Head and Neck Reconstruction-A Case Series

Background: Defects of the ascending ramus of the mandible, including the condylar head and neck or the whole temporomandibular joint (TMJ), are difficult to reconstruct. Reconstruction is mainly based on the use of alloplastic joint prosthesis, costochondral grafting, distraction osteogenesis of the dorsal part of the mandibular ramus, or osseous microvascular flaps of various origin. With the objective of developing a method that overcomes the restrictions of these methods, we recently introduced a sequential chimeric flap consisting of a lateral femoral condyle flap (LFC) and deep circumflex iliac artery flap (DCIA) for reconstruction of up to half of the mandible and the condylar head and neck. Methods: The chimeric flap was used in four patients with the following diagnoses: therapy-refractory osteomyelitis, extended recurrent odontogenic keratozyst, Goldenhar syndrome, and adenocarcinoma of the parotid gland. After a diagnostic workup, LFC and DCIA flaps were harvested in all patients and used in a sequential chimeric design for the reconstruction of the mandibular body and condylar head and neck. Results: Follow-up from at least 24 months up to 70 month after surgery showed a successful reconstruction in all four patients. The LFC provided a cartilaginous joint surface, allowing for a satisfactory masticatory function with a stable occlusion and unrestricted mouth opening and preserved or regained lateral and medial excursions in all patients. The DCIA allowed for a bony reconstruction anatomically resembling a non-atrophied mandibular body. No flap-related complications were observed. Conclusions: The sequential chimeric LFC and DCIA flap is an appropriate method for reconstructing up to half of the mandible and the condylar head and neck. It is suitable in cases where alloplastic joint replacement cannot be used or where other methods have failed. Due to the necessity of harvesting two flaps, the burden of care is increased, and a careful indication is required. The technique is reserved for maxillofacial surgeons who have already gained significant experience in the field of microsurgery.

Lateral Femoral Trochlea Osteochondral Flap Reconstruction of Proximal Pole Scaphoid Nonunions

PURPOSE

The medial femoral trochlea flap has been described as a method of scaphoid proximal pole nonunion reconstruction when the proximal pole is deemed nonsalvageable. The lateral femoral trochlea (LFT) is an alternative donor site providing a comparable vascularized convex osteochondral flap. We describe the technique and outcomes of our first 17 cases of LFT flap reconstruction of the proximal scaphoid pole with a minimum follow-up of 14 months.

METHODS

Seventeen of the first 24 patients who underwent LFT scaphoid reconstruction at 3 institutions were able to be contacted for clinical follow-up and chart reviews. We recorded patient age and sex, duration of nonunion, number of previous surgical procedures, details of surgical technique, achievement of osseous union, complications, additional postoperative procedures, preoperative and postoperative pain, and range of motion. Preoperative and postoperative scapholunate and radiolunate angles were analyzed on x-rays and achievement of osseous union on computerized tomography scans.

RESULTS

The average age of patients included was 35 years (range, 16-55 years). Follow-up data were recorded at an average of 33 months (range, 14-62 months). Ten patients had previous procedures (average, 1; range, 0-2). Median duration from trauma to LFT was 3.4 years (range, 8 months-12 years) among patients who had a recognized date of injury. Osseous healing was achieved in 16 of 17 patients and confirmed by computerized tomograpy scan. Twelve patients reported complete pain relief, while 5 reported partial pain relief. Final postoperative range of motion was 59°extension (range, 30°-85°) and 50° flexion (range, 10°-80°), which was comparable to preoperative values. Preoperative (59°) and postoperative (55°) scapholunate angles were similar to normal wrists.

CONCLUSION

Vascularized LFT flaps provide an alternative donor site for vascularized osteochondral reconstruction of proximal pole scaphoid nonunion. Rate of union, range of motion, and pain relief are similar to reported results with medial femoral trochlea flap reconstruction.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Genicular Artery Embolization: A Review of Essential Anatomic Considerations

Genicular artery embolization is increasingly recognized as a safe and effective treatment option for symptomatic knee osteoarthritis and recurrent hemarthrosis after total knee arthroplasty. Genicular arteries are an essential contributor to vascular supply for the knee joint and demonstrate considerable variability. Familiarity with the anatomy and common variations is critical for preprocedural planning, accurate target selection, and minimizing adverse events in transarterial embolization procedures. This review aimed to provide a detailed discussion of the genicular artery anatomy that is relevant to interventional radiologists performing genicular artery embolization.

Metacarpophalangeal Joint Reconstruction of a Complex Hand Injury with a Vascularized Lateral Femoral Condyle Flap Using an Individualized 3D Printed Model-A Case Report

This case report describes the surgical management of a patient with a complex hand trauma. This injury included tendon, vascular, and nerve injuries, a partial amputation of the index finger, fractures of the third proximal phalanx, and destruction of the metacarpophalangeal joint of the fifth finger. Firstly, the acute treatment of a complex hand injury is described. Secondly, the planning and execution of a joint reconstruction using a vascularized lateral femoral condylar flap, assisted by an individual 3D model, is illustrated. Precise reconstruction of the affected structures resulted in good revascularization as well as an anatomical bone consolidation. Intensive physical therapy, including autonomous proprioceptive range-of-motion exercises by the patient, resulted in significant functional improvement of the hand in daily life. Overall, we report on the successful reconstruction of a metacarpophalangeal joint by using a vascularized flap from the lateral femoral condyle. Furthermore, this case report highlights the efficacy of integrating individualized 3D printing technology to plan complex reconstructions, opening up promising opportunities for personalized and optimized interventions.

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

Background

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.

Materials and methods

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.

Results

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.

Conclusions

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.

Genicular Artery Embolization Data Review

Osteoarthritis of the knee poses an ever-expanding healthcare challenge worldwide. Current treatments include conservative methods such as weight loss, pharmacological treatments including NSAIDs, and surgical techniques including total knee arthroplasty. Although frequently successful, contraindications and failure of pharmacological agents leave many, especially with mild-moderate disease, without effective treatment. Genicular artery embolization is an interventional radiology technique being developed to fill this treatment gap. For this procedure to become established, the literature must provide evidence of its underlying scientific principles, safety, efficacy and economic viability. Pathological investigation of osteoarthritis reveals that low-level inflammation plays a crucial role in disease development. Joint inflammation stimulates neoangiogenesis and accompanying neuronal growth, with the degree of microvascular invasion being correlated with more severe pain in animal models. These neovessels provide a target for embolization however, the microscopic effects of this intervention are yet to be elucidated. The side effects of GAE have been extensively investigated with no severe adverse events being recorded. Skin discoloration and puncture site hematoma are the most common, occurring in 10%-65% and 0%-17% of patients respectively. The literature also discusses ways to minimize these events. Phase one studies provide promising evidence of efficacy, demonstrating an 80% improvement in Visual Analogue Scale (VAS) and a mean difference of 36.8 in Western Ontario and McMaster Universities Arthritis Index (WOMAC) scores at 24-months. These positive signals are also supported by a single randomized control trial. A single study has been completed regarding the cost of GAE, however further work is needed. The GAE literature demonstrates a safe procedure with promising initial evidence of efficacy. Future work should further elucidate the pathology of osteoarthritis and ways in which embolization modifies this process, alongside providing further randomized control evidence that aligns with the recommendations from the National Institute for Health and Care Excellence. The future of GAE is exciting!

Vascularized Bone Graft Reconstruction for Upper Extremity Defects: A Review

Upper extremity reconstruction may pose clinical challenges for surgeons due to the often-critical, complex functional demands of the damaged and/or missing structures. The advent of vascularized bone grafts (VBGs) has aided in reconstruction of upper extremity (UE) defects due to their superior regenerative properties compared with nonvascularized bone grafts, ability to reconstruct large bony defects, and multiple donor site options. VBGs may be pedicled or free transfers and have the potential for composite tissue transfers when bone and soft tissue are needed. This article provides a comprehensive up-to-date review of VBGs, the commonly reported donor sites, and their indications for the treatment of specific UE defects.

Lateral Femoral Trochlea Flap Reconstruction of the Proximal Capitate: An Assessment of Congruity and Description of Technique

PURPOSE

We examined morphologic similarities of the medial lateral femoral trochlea (MFT) and lateral femoral trochlea (LFT) osteochondral flaps for reconstruction of the proximal capitate.

METHODS

Magnetic resonance imaging scans of the wrists and ipsilateral knees of 10 young healthy volunteers were obtained. Three morphologic parameters were investigated, comparing the MFT and LFT harvest sites to the capitate proximal pole. The correspondingly relevant surgical planes were compared. The coronal plane radius of curvature (ROC) of the capitate was compared with the sagittal planes of the MFT and LFT. The sagittal plane ROC of the capitate was compared to the axial planes of the MFT and LFT. The angular relationship between the dorsal cortical surface of the capitate and the proximal pole cartilage (proximal dorsal capitate pitch) was compared to the corresponding angles between the cortical bone and convex cartilage on the LFT and MFT.

RESULTS

The average ratios of ROC for the coronal planes of the capitate to the MFT (0.61) and LFT (0.58) were similar. The average ratios of ROC for the sagittal planes of the capitate to the MFT (0.57) and LFT (0.86) were also similar. The proximal dorsal capitate pitch demonstrated greater similarity to the corresponding shape of the LFT (angular ratio, 1.01) than to that of the MFT (angular ratio, 0.74).

CONCLUSIONS

The LFT and MFT demonstrate similar congruity to the proximal capitate in the sagittal and coronal planes of the wrist. The LFT dorsal pitch closely approximates the relationship of the proximal capitate pole to its dorsal cortical surface.

CLINICAL RELEVANCE

In capitate fracture, fracture nonunion, or avascular necrosis, both the MFT and LFT demonstrate similarity to the proximal convex capitate morphology. The relationship between the cortical and chondral surfaces of the LFT is morphologically very similar to that of the proximal capitate.

The condylar capping for microvascular temporomandibular joint reconstruction: A preliminary study

BACKGROUND

Defects of the temporomandibular joint (TMJ) are often difficult to be reconstructed in the correct dimensions and function. This preliminary study aims to describe a novel technique of condylar reconstruction with a microvascular flap in case of deforming arthrosis of the TMJ: condylar capping.

PATIENTS AND METHODS

Four patients between 22 and 62 years old-three females and one male-with severe unilateral arthrosis of the TMJ underwent condylar capping. All patients had already had a failed conservative treatment, followed by arthroscopy with lysis and lavage and later open surgery with total or subtotal diskectomy combined with a condylar arthroplasty. Nevertheless, their pain was still at level six or more on a visual analogue scale. Moreover, they could eat only soft food. At this stage, they underwent condylar capping using an osteochondral lateral femoral condyle (LFC) flap. The surgical technique and the postoperative management are described in detail. Crucially the attachment of the lateral pterygoid muscle to the condylar neck was preserved in all cases. The patients were followed up clinically and by CT scan preoperatively, 6, and 12 months postoperatively.

RESULTS

The mean height of the reconstructed neo-condyle was 6.0 mm, the mean width 16.2 mm, and the mean sagittal length 9.8 mm. The follow-up period ranged from 14 to 64 months. The procedures were uneventful for all patients, and the donor site morbidity was negligible. Twelve months later, the patients were all pain-free and able to have a regular diet. The TMJ and the knee had a normal range of movement and power. Postoperative imaging demonstrated bone healing and stable and anatomically correct condyle reconstruction.

CONCLUSIONS

Based on the author's experience, the condylar capping with the LFC appears promising for reconstructing the condylar head in cases of severe osteoarthritis. Preserving the attachment of the lateral pterygoid muscle allows a complete restoration of the physiologic range of movement, including protrusion and laterotrusion of the mandible.

Emerging Targets for the Treatment of Osteoarthritis: New Investigational Methods to Identify Neo-Vessels as Possible Targets for Embolization

Osteoarthritis (OA) is the major cause of disability, affecting over 30 million US adults. Continued research into the role of neovascularization and inflammation related to osteoarthritis in large-animal models and human clinical trials is paramount. Recent literature on the pathogenetic model of OA has refocused on low-level inflammation, resulting in joint remodeling. As a result, this has redirected osteoarthritis research toward limiting or treating joint changes associated with persistent synovitis. The overall goal of this review is to better understand the cellular and tissue-specific mechanisms of inflammation in relation to a novel OA treatment modality, Genicular Artery Embolization (GAE). This article also assesses the utility and mechanism of periarticular neovascular embolization for the treatment of OA with a particular emphasis on the balance between pro-angiogenic and anti-angiogenic cytokines, inflammatory biomarkers, and imaging changes.

The free vascularized lateral femoral trochlea osteochondral graft: a reliable alternative for Stage III Kienböck's disease

Lunate reconstruction using a lateral femoral trochlea osteochondral graft was carried out in 27 patients with Stage III Kienböck's disease from 2012 to 2019. Twenty-three of these patients could be followed-up in this retrospective study. Ten were women and 13 men. Nine were Lichtman Stage IIIA, seven Stage IIIB and seven Stage IIIC. The mean follow-up was 39 months (range 12-86). Bony consolidation was found in 18 of the 23 patients, with no graft loss. The mean Disabilities of the Arm, Shoulder and Hand score (DASH score) was 11 and the Modified Mayo Wrist Score was 83. There were only two radiological deteriorations, with the same or improved Lichtman classifications in the other patients and a significant reduction in pain. Postoperative extension of the wrist (52°) and flexion (48°) were comparable with preoperative values and, respectively, 81% and 72% of the contralateral side. Grip strength and pinch grip were 32 kg and 12 kg, 88% and 94% of the other hand, respectively, and an insignificant increase compared with the preoperative values. The vascularized lateral femoral trochlea osteochondral graft yields good short- and mid-term results in Grade III Kienböck's disease.Level of evidence: IV.

Cadaveric and Angiographic Anatomical Considerations in the Genicular Arterial System: Implications for Genicular Artery Embolisation in Patients with Knee Osteoarthritis

PURPOSE

Genicular artery embolisation (GAE) is a novel treatment for patients with knee osteoarthritis (OA). Cadaveric dissection was undertaken to provide a complete description of the relevant arterial anatomy in order to perform safe and effective GAE.

MATERIALS

Twenty human lower limb specimens were dissected. The morphology of the genicular arteries and presence of anastomotic connections was recorded and compared with angiographic images from patients having undergone GAE. Vessels were measured to investigate the risk of non-target embolisation (NTE), taking a diameter of 300 microns as the threshold for significance.

RESULTS

The descending genicular artery (DGA) is the dominant vessel in medial OA, with 95% of cases revealing vessel division into muscular, saphenous and osteoarticular branches from a single pedicle. The superior medial genicular artery (SMGA) had a shared origin with the middle genicular artery (MGA) in 25% of cases. NTE to the MGA may damage the cruciate ligaments. In 85% of cases, there was an anastomosis between the DGA and SMGA, often encountered at angiography. The mean diameter of the anastomoses was 850 micron, presenting a risk for NTE. An anastomosis between the Inferior Medial Genicular Artery (IMGA) and medial sural artery was found in 5% of cases; the medial sural artery supplies blood to the tibial nerve and should be avoided. The IMGA and inferior lateral genicular artery provided supply to the patellofemoral joint in 69% and 88% of cases, respectively.

CONCLUSION

An in-depth knowledge of genicular artery anatomy is required for interventional radiologists to perform safe and effective GAE in patients with knee osteoarthritis.

Donor site morbidity after the harvest of microvascular flaps from the medial and lateral femoral condyle region: Objective, radiologic, and patient-reported outcome of a multi-center trial

BACKGROUND

With the experience-based hypothesis of low donor site morbidity (DSM) for free flaps from the distal femur, this cohort study aimed to evaluate the DSM according to objective and reproducible criteria.

METHODS

One hundred and fifty-six patients who had a flap harvest from either the medial or lateral femoral condyle region between 2005 and 2017 were included. A retrospective chart review was performed for all patients. In total, 97 patients were available for a follow-up examination. Outcomes were assessed according to objective (Knee Society Score; Larson Knee Score; OAK Score; 0-100 points), patient-reported (IKDC Score; KOOS Score; 0-100 points), and radiologic criteria (Kellgren and Lawrence Score; MRI Osteoarthritis Knee Score).

RESULTS

The median follow-up time was 1,529 days (range: 248-4,810). The mean Knee Society Score (94.8 ± 10.1), Larson Knee Score (94.5 ± 10.1), and OAK Score (95.5 ± 6.6) showed nearly unimpaired knee function. The overall patient-reported DSM was low (IKDC Score: 86.7 ± 17.4; KOOS Score: 89.3 ± 17.1). Osteochondral (OC) flaps had a significantly higher DSM, regardless of the donor site. Bone flaps did not show any relevant radiologic morbidity in the Kellgren and Lawrence Score. Besides the procedure-associated cartilage lesions at the OC donor sites, MRI Osteoarthritis Knee Score did not show any significant presence of further knee pathologies in the bilateral MRI Scans. The obvious cartilage lesions did not have a relevant impact on the knee function of most patients.

CONCLUSION

The DSM for bone and soft-tissue flaps from the femoral condyle region is negligible. OC flaps are associated with a significantly higher DSM, although a clinically relevant impact on knee function was not evident in the majority of patients.

The fasciocutaneous iliotibial band perforator flap in soft tissue and tendon reconstruction of the foot: A case report

In cases of large defects of the limbs, post‐traumatic deformity and disability can have devastating effects on patients' quality of life. The purpose of this report is to describe the technique for raising a fasciocutaneous iliotibial perforator flap and present its application in the reconstruction of a complex soft tissue defect of the foot. The patient was a 13‐year‐old male who had suffered a crush injury to the foot in a motor vehicle accident 5 years earlier. Due to retraction of the skin, together with the extensor tendons of the digits, the patient could not flex the digits II, III, IV, and V. To reconstruct the defect, the authors harvested a fasciocutaneous flap based on a perforator branch of the superior lateral genicular artery and accompanying veins. The immediate postoperative course was uneventful, with progressive and complete recovery of power and range of motion in the foot and knee within 6 weeks. Despite the tendency to form hypertrophic scars again, the functionality of the operated foot was excellent 29 months after the reconstruction. According to the American Orthopedic Foot and Ankle Society scale, the patient scored 100 points on the midfoot section and 93 points on the section forefoot rays two to five. The iliotibial perforator flap could be a new tool for a state‐of‐the‐art functional reconstruction of soft tissues defects of the limbs and head and neck.

Vascular coverage of the anterior knee region - an anatomical study

Descriptions of vessel angiosomes or perforasomes throughout the human body are quite frequent, and led to the development of flaps nowadays commonly used to surgically cover skin and soft tissue defects. In these procedures, the surgeon requires a profound anatomical knowledge of the respective blood vessels and the extent of the perfused area to define the size of the graft. In the region of the knee joint, descriptions of flaps based on the superior lateral genicular artery and descending genicular artery are quite frequent. In contrast, information regarding other popliteal branches is scarce or non‐existent. The aim of this study was to provide a concise and complete overview on the extent and variability of the perforator angiosomes of the femoral and popliteal arteries in the anterior knee region. Twenty lower extremities were dissected, the respective perforators identified and perfused with dye. All resulting angiosomes were marked and documented. A total of 84 angiosomes were identified in all specimens, with an average of 4.2 (3–6) angiosomes per specimen. The average size of the angiosomes was 97.04 ± 72.30 cm² (8.61–360.41 cm²), their source vessels had an average diameter of 1.42 ± 0.54 mm (0.60–3.25 mm). The complex and highly variable distribution of perforator angiosomes of the anterior knee region and especially of its less frequently investigated distal part was demonstrated. Based on these results, the planning of existing perforator flaps in this region and the development of flaps including the inferior medial or inferior lateral genicular arteries may be facilitated.

Cutaneous angiosome of the chimeric SLGA perforator flap: Anatomical study and clinical considerations

BACKGROUND

The superior lateral genicular artery (SLGA) is the basis for a chimeric perforator flap in the lateral knee region, which may include bone, cartilage, fascia, and/or skin. To the best of our knowledge, a detailed description of the corresponding perforator-based skin area is missing in the literature. The aim of this study was to describe the extent and possible variations of the cutaneous angiosome of the SLGA.

METHODS

In an anatomical study on 21 fresh frozen lower limbs, the SLGA was injected with toluidine blue. The anatomy of the vessel and its perforators was explored, and the skin containing the cutaneous angiosome was harvested and photo-documented. Evaluation of the images was performed using ImageJ software. In addition, the versatility of the SLGA perforator flap is illustrated as both a pedicled local and a free tissue transfer.

RESULTS

For each vessel, there were 1.75 ± 0.9 (range 1-3) perforators at an average position of 47.3 ± 21.3 mm lateral to the superolateral patella and 42.5 ± 18.7 mm proximal to the knee joint. The angiosome area was 222.8 ± 57.6 cm² with a length of 20.9 ± 3.0 cm and a width of 15.4 ± 3.0 cm. At the longitudinal axis of the highest perforator density, the proximal end and the distal end of perfusion averaged 13.4 ± 4.1 cm proximal and 2.5 ± 2.0 cm distal to the knee joint, respectively.

CONCLUSION

Our results show that the SLGA supplies a constant angiosome over the anterolateral proximal knee joint. Its description and visualization will guide surgeons in preoperative planning and further extend the use of this versatile chimeric perforator flap.

How to determine the surgical approach in Hoffa fractures?

Surgical approach selection and fixation of Hoffa fractures is difficult and remains controversial. Evolving trends emphasize the importance of fracture morphology, fracture location, and comminution, all of which guide decisions regarding surgical approach and implant selection. This focused review highlights factors affecting Hoffa fracture available surgical approaches, treatment outcomes, and recommendations for selecting an optimal approach.