Graft Reconstruction Research Articles

Free temporalis muscle fascia graft in dural reconstruction following surgical resection of intermediate and malignant skull base tumors: A 10-year experience from a single center.

Data from patients with post-ablative dural defects reconstructed using a free temporalis muscle fascia graft (FTFG) after resection of anterior or central skull base tumors were retrospectively analyzed. The primary predictor and outcome variables were the reconstructive methods for dural repair and postoperative cerebrospinal fluid (CSF) leakage rate, respectively. Eighty patients were included, and 94 postoperative dural reconstructions were performed using FTFG. The postoperative CSF leakage rate was 3.19%. The postoperative CSF leakage rates did not significantly differ between open and endonasal endoscopic surgeries (1.92% vs. 4.88%; p > 0.05). In cases completed using the endonasal endoscopic approach, the postoperative CSF leakage rate was significantly associated with the intraoperative CSF leak flow (p < 0.05). Post-ablative dural defect reconstruction using FTFG resulted in low postoperative CSF leakage and complication rates comparable to those of free fascia lata graft from available literature.

Numerical Study of Mechanical Development of Patient-Specific Mandibular Reconstruction Implant

Patient-specific mandibular reconstruction implants are a new technique to deal with ameloblastoma tumors. Although they could solve the integration problem which is attributed to the graft reconstruction approach, they may increase the risk of infection due to poor blood supply around it. Using bone grafts besides customized plates with smaller geometries would be considered as an alternative. However, they would also have possible complications like poor graft integration and plate fracture. Considering weight reduction patterns on implants would efficiently help to solve the mentioned problems. In this study, two design concepts of mandibular reconstruction implants which were different in weight reduction pattern’s location were presented. Also, a finite element assessment was performed to evaluate the mechanical performance and functionality of the implants under chewing load. Results revealed that designing patterns all over the implant geometry would lead to minimum jaw deviation and maximum Von Mises stress values around 120 MPa which is much less than Ti6Al4V yield stress. Compared to the solid design, the patterns would enhance the implant function by decreasing the deviation which would result in a function similar to the intact side. Although results showed the proper functionality of the implant clinical trials with multiyear follow-ups are still needed to investigate the detailed clinical results of this concept.

Reconstruction of medial meniscus posterior portion deficiency in pigs with an autologous patellar tendon graft: an experimental study

ObjectiveThis study was performed to investigate the effectiveness of two surgical procedures, autologous patellar tendon graft reconstruction and trans-tibial plateau pull-out repair, using a pig model. The primary focus was to assess the repair capability of medial meniscus posterior portion (MMPP) deficiency, the overall structural integrity of the meniscus, and protection of the femoral and tibial cartilage between the two surgical groups. The overall aim was to provide experimental guidelines for clinical research using these findings.MethodsTwelve pigs were selected to establish a model of injury to the MMPP 10 mm from the insertion point of the tibial plateau. They were randomly divided into three groups of four animals each: reconstruction (autologous tendon graft reconstruction of the MMPP), pull-out repair (suture repair of the MMPP via a trans-tibial plateau bone tunnel), and control (use of a normal medial meniscus as the negative control). The animals were euthanized 12 weeks postoperatively for evaluation of the meniscus, assessment of tendon bone healing, and gross observation of knee joint cartilage. The tibial and femoral cartilage injuries were evaluated using the International Society for Cartilage Repair (ICRS) grade and Mankin score. Histological and immunohistochemical staining was conducted on the meniscus–tendon junction area, primary meniscus, and tendons. The Ishida score was used to evaluate the regenerated meniscus in the reconstruction group. Magnetic resonance imaging (MRI) was used to evaluate meniscal healing.ResultsAll 12 pigs recovered well after surgery; all incisions healed without infection, and no obvious complications occurred. Gross observation revealed superior results in the reconstruction and pull-out repair groups compared with the control group. In the tibial cartilage, the reconstruction group had ICRS grade I injury whereas the pull-out repair and control groups had ICRS grade II and III injury, respectively. The Mankin score was significantly different between the reconstruction and control groups; histological staining showed that the structure of the regenerated meniscus in the reconstruction group was similar to that of the original meniscus. Immunohistochemical staining showed that the degree of type I and II collagen staining was similar between the regenerated meniscus and the original meniscus in the reconstruction group. The Ishida score was not significantly different between the regenerated meniscus and the normal primary meniscus in the reconstruction group. MRI showed that the MMPP in the reconstruction and pull-out repair groups had fully healed, whereas that in the control group had not healed.ConclusionAutologous patellar tendon graft reconstruction of the MMPP can generate a fibrocartilage-like regenerative meniscus. Both reconstruction and pull-out repair can preserve the structural integrity of the meniscus, promote healing of the MMPP, delay meniscal degeneration, and protect the knee cartilage.

Novel Dual Bicolumnar Fibula Graft Reconstruction of Distal Humerus in Pediatric Patients After Massive Bone Resection: A Report of Two Cases.

We describe 2 case studies, involving a 10-year-old girl with an aneurysmal bone cyst and a 12-year-old adolescent boy with Ewing sarcoma. The patient with Ewing sarcoma was previously managed with wide surgical excision and fibular graft reconstruction and subsequently experienced significant graft resorption, hardware failure, and fracture 24 months after operation. A revision limb salvage attempt was undertaken. In both cases, fibular strut grafts were harvested and fixed with intramedullary k-wires to recreate the medial and lateral columns of the distal humeral triangle. The technique achieved complete osseous integration, structural support, and functional restoration of the elbow in both cases, with good functional outcomes.

The Heel Complex: Anatomy, Imaging, Pathologic Conditions, and Treatment.

The differential diagnosis for heel pain is broad but primarily involves abnormalities of the Achilles tendon, calcaneus, and plantar fascia. Achilles tendon disorders include tendinosis, tendinitis, and partial or complete tears. Tendinosis refers to tendon degeneration, while tendinitis is inflammation after acute overload. Untreated tendinosis can progress to partial or complete tears. Tendon disorders can be accompanied by paratenonitis or inflammation of the loose sheath enclosing the tendon. Initial management involves rehabilitation and image-guided procedures. Operative management is reserved for tendon tears and includes direct repair, tendon transfer, and graft reconstruction. The calcaneus is the most commonly fractured tarsal bone. The majority of fractures are intra-articular; extra-articular fractures, stress or insufficiency fractures, medial process avulsion, and neuropathic avulsion can also occur. Posterosuperior calcaneal exostosis or Haglund deformity, retrocalcaneal bursitis, and insertional Achilles tendinosis form the characteristic triad of Haglund syndrome. It is initially managed with orthotics and physiotherapy. Operative management aims to correct osseous or soft-tissue derangements. The plantar fascia is a strong fibrous tissue that invests the sole of the foot and contributes to midfoot stability. Inflammation or plantar fasciitis is the most common cause of heel pain and can be related to overuse or mechanical causes. Acute rupture is less common but can occur in preexisting plantar fasciitis. Conservative treatment includes footwear modification, calf stretches, and percutaneous procedures. The main operative treatment is plantar fasciotomy. Plantar fibromatosis is a benign fibroblastic proliferation within the fascia that can be locally aggressive and is prone to recurrence. ©RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material.

Biomechanical Stability of Third-Generation Adjustable Suture Loop Devices Versus Continuous Loop Button Device for Cortical Fixation of ACL Tendon Grafts.

Concerns regarding the primary stability of early adjustable loop button (ALB) devices for cortical fixation of tendon grafts in anterior cruciate ligament reconstruction (ACLR) have led to the development of new implant designs. To evaluate biomechanical stability of recent ALB implants in comparison with a continuous loop button (CLB) device. Controlled laboratory study. ACLR was performed in a porcine model (n = 40) using 2-strand porcine flexor tendons with a diameter of 8 mm. Three ALB devices (Infinity Button [ALB1 group]; Tightrope II RT [ALB2 group]; A-TACK [ALB3 group]) and 1 CLB device (FlippTack with polyethylene suture) were used for cortical tendon graft fixation. Cyclic loading (1000 cycles up to 250 N) with complete unloading were applied to the free end of the tendon graft using a uniaxial testing machine, followed by load to failure. Elongation, stiffness, yield load, and ultimate failure load were recorded and compared between the groups using a Kruskal-Wallis test with post hoc Dunn correction. Elongation after 1000 cycles at 250 N was similar between groups (ALB1, 4.5 ± 0.7 mm; ALB2, 4.8 ± 0.8 mm; ALB3, 4.5 ± 0.6 mm; CLB, 4.5 ± 0.8 mm), as was load to failure (ALB1, 838 ± 109 N; ALB2, 930 ± 89 N; ALB3, 809 ± 103 N; CLB, 842 ± 80 N). Stiffness was significantly higher in the ALB1 group compared with the CLB group (262.3 ± 21.6 vs 229.3 ± 15.1 N/mm; P < .05). No significant difference was found between the 4 groups regarding yield load. Constructs failed either by rupture of the loop, breakage of the button, or rupture of the tendon. The tested third-generation ALB devices for cortical fixation in ACLR withstood cyclic loading with complete unloading without significant differences to a CLB device. The third-generation ALB devices tested in the present study provided biomechanical stability comparable with that of a CLB device. Furthermore, ultimate failure loads of all tested implants exceeded the loads expected to occur in the postoperative period after ACLR.

Surgical Resection and Reconstruction of Ameloblastoma: A 13-Year Retrospective Review

Ameloblastoma is a locally aggressive, benign tumor presenting in the maxilla and mandible prone to recurrence. Resection greatly limits recurrence; however, reconstruction becomes critical to preserve patients' functionality and esthetics. The aim of this study was to describe surgical resection and reconstructive approaches in the treatment of ameloblastoma and compare clinical outcomes to conservative methods of treatment. A retrospective case series was completed through analysis of patient records. The study population was composed of patients treated for ameloblastoma at the Royal Brisbane Hospital (Queensland, Australia) in the Oral and Maxillofacial Surgery Unit from January 1, 2008, to December 31, 2020. Patients without histological confirmation of intraosseous ameloblastoma were excluded from the study sample. Not applicable. The primary outcome variable was time to recurrence. Secondary outcome variables included any surgical complications incurred. The covariate variables collected included age at diagnosis/treatment, gender, ethnicity, location of lesion and site(s) of involvement, tumor extent, alveolar expansion, histopathological growth pattern, and soft tissue involvement. Descriptive statistics were computed for each study variable. A total of 48 cases of histologically confirmed ameloblastoma were identified (41 mandibular, 7 maxillary) involving 50 excisional operations (44 resections, 6 enucleations). Of these cases, 44 were followed up>12months, with a mean length of follow-up time of 65.6months. No recurrence was detected for resected lesions. One enucleated lesion recurred at 25months. Thirty-seven reconstructive procedures were undertaken, including 32 immediate free flaps. All reconstructive flaps and grafts survived, and no major complications were recorded. Resection of ameloblastoma limits recurrence and should be considered curative. Immediate microvascular free flap reconstruction of maxillary and mandibular defects from resection of ameloblastoma is safe and predictable.

СПОСОБ ЛЕЧЕНИЯ ЛОЖНЫХ СУСТАВОВ ЛАДЬЕВИДНОЙ КОСТИ ПУТЕМ ПРИМЕНЕНИЯ НАДКОСТНИЧНЫХ ЛОСКУТОВ НА МЕТАКАРПАЛЬНЫХ АРТЕРИЯХ

The purpose of the study: to improve the method of surgical treatment of patients with scaphoid nonunion. Material and methods: the results of treatment of 30 patients operated on for scaphoid nonunion of the hand, which arose after conservative treatment (not treatment) of fractures, surgical treatment for 2018-2021 were analyzed. The patients were divided into two groups: 15 patients with scaphoid nonunion who underwent free bone autoplasty as a surgical aid, fixation of bone fragments with a headless screw – a control group; 15 patients with fscaphoid nonunion, who underwent free bone autoplasty as surgical treatment, supplemented with non-free plastic surgery with a periosteal flap on the metacarpal artery – the main (experimental) group of patients. The possibility of using periosteal flaps isolated from the first and second metacarpal bones was evaluated. To assess the results of treatment, X-ray monitoring of scaphoid nonunion consolidation was used at 8, 12 weeks and 6 months after surgery; computed tomography of wrist joints was performed at 4 months after surgery in order to assess the degree of bone graft reconstruction. Hand function was assessed before and after surgery using the DASH Upper Limb Disability Questionnaire and the Visual Analog Pain Scale (VAS). Results of the study: in the experimental group, scaphoid nonunion consolidation was achieved in 13 out of 15 patients (86.6%) compared with the control group (10 out of 15 patients – 66.7%). According to the severity of the pain syndrome and the final functional result, comparable indicators were obtained in both groups. Discussion: given the small sample of patients who participated in the work, the study has moderate reliability. However, the data obtained allow us to hope for the effectiveness of the proposed method of surgical treatment used in patients of the main study group.

Functional and aesthetic outcomes of dermofat graft reconstruction in limited parotidectomy defects: a cross-sectional study

Functional and aesthetic outcomes of dermofat graft reconstruction in limited parotidectomy defects: a cross-sectional study

Use of Fibular Strut Graft for Reconstruction of Bone Defects

Introduction • Bone recalcitrant nonunion and bone defects usually follow trauma, resection of a malignant tumor of the musculoskeletal system and osteomyelitis. • Instead of amputation, which was used in the past, limb salvage surgeries, including non-vascularized or vascularized autografts and allografts, bone transport and replacement with prostheses are performed. • Among the above methods, nonvascularized autogenous bone graft use is an important treatment strategy that has been performed for over a hundred years. • The fibula is a tubular bone that has a suitable length, geometrical shape and mechanical strength and is considered to be the best donor bone for large bone defects. • Free vascularized fibular grafts achieve higher union rate than non-vascularized fibular grafts in the reconstruction of long bone defects. • In this study, 6 patients with bone defects treated by non-vascularized fibular grafts .We intended to assess the clinical outcomes of graft union, functional outcome.

Bioengineering autologous cartilage grafts for functional posterior lamellar eyelid reconstruction: A preliminary study in rabbits

The reconstruction of posterior lamellar eyelid defects remains a significant challenge in clinical practice due to anatomical complexity, specialized function, and aesthetic concerns. The ideal substitute for the posterior lamellar should replicate the native tarsoconjunctival tissue, providing both mechanical support for the eyelids and a smooth surface for the globe after implantation. In this study, we present an innovative approach utilizing tissue-engineered cartilage (TEC) grafts generated from rabbit auricular chondrocytes and a commercialized type I collagen sponge to reconstruct critical-sized posterior lamellar defects in rabbits. The TEC grafts demonstrated remarkable mechanical strength and maintained a stable cartilaginous phenotype both in vitro and at 6 months post-implantation in immunodeficient mice. When employed as autografts to reconstruct tarsal plate defects in rabbits’ upper eyelids, these TEC grafts successfully restored normal eyelid morphology, facilitated smooth eyelid movement, and preserved the histological structure of the conjunctival epithelium. When applied in bilayered tarsoconjunctival defect reconstruction, these TEC grafts not only maintained the normal contour of the upper eyelid but also supported conjunctival epithelial cell migration and growth from the defect margin towards the centre. These findings highlight that auricular chondrocyte-based TEC grafts hold great promise as potential candidates for clinical posterior lamellar reconstruction. Statement of significanceThe complex structure and function of the posterior lamellar eyelid continue to be significant challenges for clinical reconstructive surgeries. In this study, we utilized autologous auricular chondrocyte-based TEC grafts for posterior lamellar eyelid reconstruction in a preclinical rabbit model. The TEC grafts exhibited native cartilaginous histomorphology and comparable mechanical strength to those of the native human tarsal plate. In rabbit models with either tarsal plate defects alone or bilayered tarsoconjunctival defects, TEC grafts successfully restored the normal eyelid contour and movement, as well as supported preservation and growth of conjunctival epithelium. This is the first study to demonstrate autologous TEC grafts can be employed for repairing tarsal plate defects, thereby offering an alternative therapeutic approach for treating posterior lamellar defects in clinic settings.

Combined Amniotic Membrane and Self-Powered Electrical Stimulator Bioelectronic Dress Promotes Wound Healing.

Human amniotic membranes (hAMs) are widely used as wound management biomaterials, especially as grafts for corneal reconstruction due to the structure of the extracellular matrix and excellent biological properties. However, their fragile nature and rapid degradation rate hinder widespread clinical use. In this work, we engineered a novel self-powered electronic dress (E-dress), combining the beneficial properties of an amniotic membrane and a flexible electrical electrode to enhance wound healing. The E-dress displayed a sustained discharge capacity, leading to increased epidermal growth factor (EGF) release from amniotic mesenchymal interstitial stem cells. Live/dead staining, CCK-8, and scratch-wound-closure assays were performed in vitro. Compared with amniotic membrane treatment alone, the E-dress promoted cell proliferation and migration of mouse fibroblast cells and lower cytotoxicity. In a mouse full-skin defect model, the E-dress achieved significantly accelerated wound closure. Histological analysis revealed that E-dress treatment promoted epithelialization and neovascularization in mouse skin. The E-dress exhibited a desirable flexibility that aligned with tissue organization and displayed maximum bioactivity within a short period to overcome rapid degradation, implying great potential for clinical applications.

Efficacy of bone ring grafts for the reconstruction of alveolar ridge deficiencies: a systematic review. Part II: animal trials.

Bone ring (BR) grafts have been introduced to reconstruct alveolar ridge defects with simultaneous implant placement, but their clinical effectiveness remains undetermined. The aim of the current systematic review was to critically appraise evidence from animal studies regarding the effectiveness of BR grafts in alveolar ridge reconstruction and their variations under different surgical protocols. Electronic retrieval of six databases (MEDLINE, Embase, Cochrane Library, ScienceDirect, Web of Science, and Scopus) and citation search until 11 October 2023, for animal studies on bone augmentation employing BR grafts. The outcome variables were total bone area (BA), bone volume (BV), bone-implant contact (BIC), and histology. The protocol was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and prospectively registered with PROSPERO (CRD42023453949). Ten studies were included in the qualitative analysis according to the screening criteria. Two studies demonstrated favorable bone remodeling and osseointegration of the BR with both the implant and pristine bone. A comparative study between autogenous BRs and allogenic BRs reported a higher percentage of BA and BIC at 4 months of healing, but conflicting data were observed at 8 months. Another study indicated a significant advantage of autogenous BRs over bovine and biphasic ceramic BRs in terms of BA and BIC after 5 weeks. Three studies found that using collagen membranes did not significantly affect BA, BV, or BIC when used simultaneously with autogenous BRs during implant placement. Two studies evaluated one-stage and two-stage implant placement in conjunction with BR grafts, revealing similar levels of BA, BV, and BIC except for differences in total treatment time. Furthermore, one study found that the use of mucogingival junction incision and split-thickness flap significantly reduced the incidence of wound dehiscence compared with conventional incision and flap. Vertical bone augmentation surgery utilizing BR grafts with one-stage implant placement yielded histological and histomorphometric outcomes comparable to those achieved with two-stage implant placement or the additional application of collagen membrane.

Efficacy of bone ring grafts for the reconstruction of alveolar ridge deficiencies: A systematic review. Part I: Clinical trials.

Bone ring (BR) grafts have been introduced to reconstruct alveolar ridge defects with simultaneous implant placement, but its clinical effectiveness remains undetermined. This systematic review aimed to comprehensively investigate BR grafts in diverse scenarios of ridge defect with simultaneous or staged implant placement. Electronic retrieval of MEDLINE, Embase, Cochrane Library(CENTRAL), Web of Science, Scopus, and citation search until August 3, 2023, was used to identify relevant clinical articles that utilized BR grafts for ridge defect reconstruction. The quality of evidence in the studies reviewed was assessed with the Joanna Briggs Institute Critical Appraisal tool. The protocol was registered in Prospective Register of Systematic Reviews (CRD42023453943). Fourteen studies with 251 BRs were identified, of which 8 studies were for alveolar ridge augmentation, 4 studies were for extraction socket augmentation, and 2 studies were for sinus floor elevation. Reported sources of BRs included autografts, allografts, and xenografts. The follow-up period ranged from 4 months to 4.7 years. Regarding the primary outcomes, the utilization of BR grafts demonstrated favorable bone gain along with acceptable graft absorption and marginal bone loss. Regarding the secondary outcomes, satisfactory bone mineral density and implant stability were confirmed, accompanied by a recorded incidence of postoperative complications (20 cases) and an implant failure rate of 5.58%. BR grafting with simultaneous or staged implant insertion is an effective approach for reconstructing alveolar ridge deficiencies. The BR grafts demonstrate favorable bone remodeling and osteointegration with the alveolar bone and implant; however, its success may be compromised by complications. Future studies should further investigate the clinical efficacy of BR grafting comparing to other bone augmentation techniques in diverse scenarios.

Efficacy of allogenic bone block graft in maxillary alveolar ridge reconstruction: A systematic review.

The purpose of this systematic review was to assess the efficiency of allogenic bone block grafts for maxillary alveolar ridge reconstruction. An electronic literature search was conducted using the PubMed, Cochrane Library, and Google Scholar databases. In addition, manual searching was done. Randomized controlled trials (RCTs) and prospective clinical trials (non-RCTs) up to December 2022, presenting the outcomes of allogenic bone blocks in maxillary alveolar ridge reconstruction, were identified. The rate of resorption, survival rate of implants, and formation of new bone following ridge augmentation were the outcome parameters. The quality assessment of the studies included was done using Joanna Briggs Institute Critical Appraisal Tool. A total of 13 studies that matched the inclusion criteria were included. The average rate of bone resorption ranged from 0.2 to 29.2 mm, with an implant survival rate of 96.87% across the included investigations. On an average, 25.83 mm (18.6-33/mm) of new mature compact osseous tissue was discovered, including viable osteocytes in close contact with the remnant cancellous bone. According to the results of the current systematic review, using allogenic bone block graft for reconstruction of atrophic maxillae appears to be an effective and reliable bone substitute for reconstruction of atrophic maxillae.

Technical considerations and long-term results of endovascular venous stenting to control venous hypertension from meningiomas invading intracranial venous sinuses.

Meningiomas invading the intracranial venous sinuses may cause intracranial venous hypertension, papilledema, and visual compromise. Sinus resection and graft reconstructions, however, add significant complexity to tumor surgery, with the potential for increased morbidity. In this study, the authors explored whether venous sinus stenting might provide an alternative means of controlling venous hypertension that would be sustainable over the long term. The authors performed a retrospective review of all 16 patients with intracranial meningiomas who underwent stenting at their institution for venous sinus compromise. At presentation, all had headache and 9 had papilledema. Thirteen patients had 1 meningioma and 3 had 2 or more. Three patients had had previous tumor resection and radiotherapy. One patient had been treated with a lumboperitoneal shunt and radiotherapy. The median length of clinical follow-up was 8 years (range 4 months-18 years). Venous sinus narrowing was often not confined to the site of meningioma, and bilateral transverse sinus narrowing, reminiscent of that seen in idiopathic intracranial hypertension, was present in 7 patients with sagittal sinus meningiomas. Eleven patients had stents placed solely across sinus narrowing caused by meningioma. Five patients had additional stents placed at other sites of venous narrowing at the same time: in one of these patients, a stent was placed across a defect in the sagittal sinus caused by previous surgery, and in the 4 other patients, stents were placed across nontumor narrowings of the transverse sinuses. In 1 patient, the jugular vein was also stented. Nine patients developed symptomatic in-stent restenosis at the meningioma site. Eight had further stenting procedures with variable success in restoring the in-stent lumen. The remaining patient, with a late partial relapse, is being reinvestigated. Papilledema resolved in all patients after stenting. Six patients experienced prolonged and very substantial relief of all symptoms. Five patients had persistent headache despite restoration of the sinus lumen. Five had persistent symptoms associated with resistant in-stent stenosis. There were no significant complications from any of the diagnostic or therapeutic procedures. In patients who are symptomatic with meningiomas obstructing the venous sinuses, successful stenting of the affected segment can give a good outcome, especially in terms of relieving papilledema. However, further procedures are often necessary to maintain stent patency, other areas of venous compromise frequently coexist, and some patients remain symptomatic despite apparently successful treatment of the index lesion. Long-term surveillance is a requirement.

Estimation of Diameter of Quadrupled Hamstring Graft for ACL Reconstruction using Pre-operative MRI Measurement as a Predictive Tool.

The diameter of the quadrupled Hamstring graft plays a significant role in the incidence of graft failures for ACL reconstruction. The ability to predict the graft size pre-operatively can prepare the surgeon for alternatives in the event of an inadequate graft diameter. We retrospectively measured the diameter of the Semitendinosus tendon (ST) on the MRI in all patients who underwent arthroscopic ACL reconstruction using quadrupled Semitendinosus as their graft. We also estimated any correlation between various anthropometric data with pre-operative MRI based Cross Sectional Area (CSA) of the Hamstring tendon and final graft diameter in the South Asian population. The patients were included from Jan 2018 - Dec 2020. The minimum CSA of ST to predict an eventual graft diameter of 7.5mm was 10.7mm2. The MRI based cross-sectional area measurement showed moderate correlation with the intra-operative graft diameter obtained. (r=0.62, p<0.001). The intra-class correlation coefficient between the radiologist and the surgeon was 0.82, 95% CI (0.57, 0.92) and a p-value <0.001. Pre-operative MRI can be a useful tool to predict the graft diameter. This coupled with the anthropometric data of the patient can be used as an adjunct to estimate the probable graft diameter. Thus, the surgeon can be better prepared for the surgery and can seek alternate graft options if the graft size is deemed inadequate pre-operatively.

Anatomic Popliteus Tendon and Tibiofibular Joint Reconstructions

Background: The popliteus tendon is a primary stabilizer of external knee rotation and has been described as the “fifth ligament of the knee.” Injuries involving the posterolateral corner of the knee commonly involve the popliteus tendon; isolated injury to the popliteus tendon is relatively rare and usually involves a rotatory injury mechanism and symptoms of instability and pain. In this patient, there was a concomitant injury to the proximal tibiofibular joint. Indications: Popliteus tendon reconstruction is indicated for patients with abnormal external rotation on examination and symptoms of pain and instability. Proximal tibiofibular joint reconstruction is indicated for patients with instability of the tibiofibular joint. Technique Description: Preoperative examination under anesthesia is essential to determine the extent of external rotation and assess for additional posterolateral pathology. The popliteus tendon procedure begins with a meticulous common peroneal nerve neurolysis to minimize nerve irritation and decrease the risk of a postoperative foot drop. Semitendinosus and gracilis graft harvest is performed with at least 16 cm of graft length followed by tunnel reaming of the popliteus tendon femoral attachment and tibia tunnel identification and reaming. The femoral attachment of the popliteus tendon is secured, and the semitendinosus graft is anatomically oriented along the native path and passed from posterior to anterior through the femoral tunnel. The gracilis graft for anatomic proximal tibiofibular joint reconstruction requires an anterior to posterior tunnel through the fibular head. Finally, both grafts are secured in the tibial tunnel with the application of an anterior traction force. Results: A cadaveric study by LaPrade et al reported that an anatomic popliteus tendon reconstruction with a semitendinosus autograft significantly reduced external rotation laxity compared with the sectioned state. In addition, popliteus tendon reconstruction resulted in significantly decreased varus laxity, anterior tibial translation, and internal rotation. Discussion: This is a technique that effectively restores external rotation knee stability utilizing an anatomically oriented reconstruction of the popliteus tendon and tibiofibular joint. The popliteus tendon serves as a primary stabilizer to external rotation and facilitates static function of the knee. The proximal tibiofibular joint reconstruction restores the function of the posterior proximal tibiofibular joint ligaments. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Effect of Posterior Tibial Slope on Outcomes After Posterior Cruciate Ligament Reconstruction.

Increased posterior tibial slope (PTS) leads to a relative anterior translation of the tibia on the femur. This is thought to decrease the stress on posterior cruciate ligament (PCL) reconstruction (PCLR) grafts. The purpose of this study was to analyze the effect of PTS on knee laxity, graft failure, and patient-reported outcome (PRO) scores after PCLR without concomitant anterior cruciate ligament reconstruction (ACLR). It was hypothesized that patients with higher PTS would have less knee laxity, fewer graft failures, and better PROs compared with patients with lower PTS. Case-control study; Level of evidence, 3. All patients who underwent PCLR between 2001 and 2020 at a single institution were identified. Patients were excluded if they underwent concomitant or prior ACLR or proximal tibial osteotomy, were younger than 18 years, had <2 years of in-person clinical follow-up, and did not have documented PRO scores (Lysholm score and International Knee Documentation Committee [IKDC] score). Data were collected retrospectively from a prospectively gathered database. PTS measurements were recorded from perioperative lateral knee radiographs. A linear regression model was created to analyze PTS in relation to PRO scores. Patients with a grade 1 (1-5 mm) or higher posterior drawer were compared with those who had a negative posterior drawer. A total of 37 knees met inclusion criterion; the mean age was 30.7 years at the time of surgery. The mean clinical follow-up was 5.8 years. No significant correlation was found between either the Lysholm score or the IKDC score and the PTS. Twelve knees (32.4%) had a positive posterior drawer at final follow-up. The mean PTS in knees with a positive posterior drawer was 6.2°, whereas that for knees with a negative posterior drawer was 8.3° (P = .08). No significant differences in PRO scores were identified for knees with versus knees without a positive posterior drawer. No documented graft failures or revisions were found. No significant differences were found in PROs or graft failure rates based on PTS at a mean of 5.8 years after PCLR. Increased tibial slope trended toward being protective against a positive posterior drawer, although this did not reach statistical significance.

Ex vivo evaluation of 3 different right ventricular outflow tract substitutes.

The Ross procedure represents an excellent treatment option in younger patients with aortic stenosis but is limited by poor availability of homografts. In this study, we investigated the hydrodynamic performance of 3 different types of right ventricular outflow tract replacement with pericardium or synthetic material. Three different types of valved conduits were constructed using pericardium and/or synthetic material (Group PEPE: pericardial cusps and pericardial conduit, Group PEPR: pericardial cusps and Dacron conduit, Group PRPR: expanded polytetrafluoroethylene cusps and Dacron conduit). The conduits were designed according to the Ozaki method. Their hydrodynamic performance (effective orifice area, mean pressure gradient and leakage volume) were evaluated in a mock circulation loop at different hydrodynamic conditions. Hydrodynamic assessment showed significantly larger effective orifice area of PEPE and PEPR compared to PRPR under all conditions and there were no significant differences between PEPE and PEPR [for condition 2: PEPE 2.43 (2.35-2.54) cm2, PEPR: 2.42 (2.4-2.5) cm2, PRPR: 2.08 (1.97-2.21) cm2, adjusted pairwise comparisons: PEPE versus PEPR: P = 0.80, PEPE versus PRPR: P < 0.001, PEPR versus PRPR: P < 0.001]. Mean pressure gradient was significantly lower for PEPE and PEPR compared with PRPR, whereas no significant differences were seen between PEPE and PEPR. Leakage volume was significantly lower for PEPE and PEPR compared with PRPR under all conditions while leakage was similar between PEPE and PEPR. Pulmonary graft reconstruction with pericardium cusps showed superior hydrodynamic performance compared with polytetrafluoroethylene cusps. Our results suggest that it could be considered as an alternative substitute for right ventricular outflow tract replacement during the Ross procedure.