Fluoroscopy guided teardrop technique for open trans-muscular iliac screw placement and open reduction maneuvers during modified triangular spinopelvic fixation for unstable U-shaped sacral and tile C pelvic traumas: technical note.

Unstable traumas of the spinopelvic junction, which include displaced U-shaped sacral fractures (Roy-Camille type 2 and type 3) and Tile C vertical shear pelvic ring disruptions, occur in severe traumas patients following high speed traffic accident or fall from a height. These unstable traumas of the spinopelvic junction jeopardize one's ability to stand and to walk by disrupting the biomechanical arches of the pelvis, and may also cause cauda equina syndrome. Historically, such patients were treated with bed rest and could suffer a life-long burden of orthopedic and neurological disability. Since Schildhauer pioneer work back in 2003, triangular spinopelvic fixation, whether it is performed in a percutaneous fashion or by open reduction and internal fixation, allows to realign bone fragments of the spinopelvic junction and to resume walking within three weeks. Nevertheless, such procedure remains highly technical and it not encountered very often, even for spine surgeons working in high-volume level 1 trauma centers. Hence, this visual technical note aims to provide a few tips to guide less experience surgeons to complete this procedure safely.

The fusion rates at different times of cortical iliac crest autograft or allograft compared with cages after anterior cervical discectomy and fusion: a meta-analysis.

OBJECTIVE: The cortical iliac crest autograft (CICA)/structural allograft (SA) has still been recognized as the gold standard for the ACDF technique for its high degree of histocompatibility and osteoinduction ability though the flourishing and evolving cage development. However, there was no further indication for using CICA/SA in ACDF based on basic information of inpatients. Our operative experience implied that applying CICA/SA has an advantage on faster fusion but not the long-term fusion rate. Therefore, our study aimed to compare the fusion rates between CICA and cage, between SA and cage, and between CICA/CA and cage. METHODS: Based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), a comprehensive literature search of electronic databases including PubMed, Embase, Cochrane Library and Web of Science was conducted to identify these clinical trials that investigated the postoperative 3, 6, 12 and 24 months fusion rates of CICA/structural SA versus cage. Assessment of risk of bias, data extraction and statistical analysis were then carried out by two independent authors with the resolve-by-consensus method. The primary outcome was fusion rate at 3, 6, 12 and 24 months postoperatively. The secondary outcomes were also meta-analyzed such as hardware complications, operative duration and hospitalization time. Our meta-analysis was registered with PROSPERO (Identifier: CRD42022345247). RESULT: A total of 3451 segments (2398 patients) derived from 34 studies were included after the screening of 3366 articles. The segmental fusion rates of CICA were higher than cages at 3 (P = 0.184, I2 = 40.9%) and 6 (P = 0.147, I2 = 38.8%) months postoperatively, but not 12 (P = 0.988, I2 = 0.0%) and 24 (P = 0.055, I2 = 65.6%) months postoperatively. And there was no significant difference in segmental fusion rates between SA and cage at none of 3 (P = 0.047, I2 = 62.2%), 6 (P = 0.179, I2 = 41.9%) and 12 (P = 0.049, I2 = 58.0%) months after operations. As for secondary outcomes, the CICA was inferior to cages in terms of hardware complications, operative time, blood loss, hospitalization time, interbody height, disk height and Odom rating. The hardware complication of using SA was significantly higher than the cage, but not the hospitalization time, disk height, NDI and Odom rating. CONCLUSION: Applying CICA has an advantage on faster fusion than using a cage but not the long-term fusion rate in ACDF. Future high-quality RCTs regarding the hardware complications between CICA and cage in younger patients are warranted for the deduced indication.

Iliac crest bone graft versus cell-based grafts to augment spinal fusion: a systematic review and meta-analysis.

INTRODUCTION: Despite successful fusion rates with iliac crest bone graft (ICBG), donor-site morbidity and increased operating time remain a considerable limitation and drive the search for alternatives. In this systematic review, grafts with additional cellular supplementation were compared with ICBG for spinal arthrodesis. We compared safety, efficacy and long-term outcomes, thus providing the current and relevant evidence for orthopaedic surgeons to make informed choices regarding this rapidly developing field. METHODS: An electronic literature search was conducted according to the PRISMA guidelines by two independent reviewers for articles published up to 1st March 2023 using PubMed, EMBASE and the Cochrane Central Register of Controlled Trial. Cellular allografts were not included. The following data were extracted: Number of patients, type of graft, fusion assessment method, follow-up duration, fusion rates, clinical outcomes and complications. The methodological quality of evidence (MQOE) was assessed using the Risk of Bias 2 (RoB-2) tool and Risk of Bias In Non-Randomised Studies (ROBINS) tool developed by Cochrane for evaluating bias in randomised and non-randomised studies. RESULTS: Ten studies fulfiled the inclusion criteria, including 465 patients. The mean number of patients per study was 43.8 (std dev. 28.81, range 12-100). Two studies demonstrated cell-based therapy to be significantly more successful in terms of fusion rates compared to ICBG. However, the remaining eight demonstrated equivocal results. No study found that cell-based therapy was inferior. No difference was seen between the two groups in three studies who focused on degenerative cohorts. No difference in functional outcome scores was seen between the groups. A number of different preparation techniques for cell-based grafts were used throughout the studies. CONCLUSION: Cell-based therapy offers a promising alternative to ICBG in spinal fusion surgery, which could help reduce the associated morbidity to patients. This review found that cell-based therapy is non-inferior to iliac crest bone graft and may offer patients an alternative treatment option with fewer complications and reduced post-operative pain. However, the literature to date is limited by heterogeneity of the cell preparation and grafting process. Future research with a unified approach to the cell preparation process is required to fully delineate the potential advantages of this technology.

Connecting the S2 alar-iliac screw head to the satellite rod for surgical correction of degenerative sagittal imbalance.

PURPOSE: The S2AI screw technique has several advantages over the conventional iliac screw fixation technique. However, connecting the S2AI screw head to the main rod is difficult due to its medial entry point. We introduce a new technique for connecting the S2AI screw head to a satellite rod and compare it with the conventional method of connecting the S2AI screw to the main rod. METHODS: Seventy-four patients who underwent S2AI fixation for degenerative sagittal imbalance and were followed up for ≥ 2 years were included. All the patients underwent long fusion from T9 or T10 to the pelvis. The S2AI screw head was connected to the satellite rod (SS group) in 43 patients and the main rod (SM group) in 31 patients. In the SS group, the satellite rod was placed medial to the main rod and connected by the S2AI screw and domino connectors. In the SM group, the main rod was connected directly to the S2AI screw head and supported by accessory rods. Radiographic and clinical outcomes were evaluated in both groups. RESULTS: There were no significant differences in postoperative complications, including proximal junctional failure, proximal junctional kyphosis, rod breakage, screw loosening, wound problems, and infection between the two groups. Furthermore, the correction power of sagittal deformity and clinical results in the SS group were comparable to those in the SM group. CONCLUSION: Connecting the S2AI screw to the satellite rod is a convenient method comparable to the conventional S2AI connection method in terms of radiological and clinical outcomes.

Preoperative supine pelvic incidence predicts standing pelvic incidence following S2AI fixation in patients with adult spinal deformity: a prospective study.

STUDY DESIGN: A prospective study. OBJECTIVE: The aim of this study was to investigate the PI change in different postures and before and after S2­alar­iliac (S2AI) screw fixation, and to investigate whether pre-op supine PI could predict post-op standing PI. Previous studies have reported PI may change with various positions. Some authors postulated that the unexpected PI change in ASD patients could be due to sacroiliac joint laxity, S2-alar-iliac (S2AI) screw placement, or aggressive sagittal cantilever technique. However, there was a lack of investigation on how to predict post-op standing PI when making surgical strategy. METHODS: A prospective case series of ASD patients undergoing surgical correction with S2AI screw placement was conducted. Full-spine X-ray films were obtained at pre-op standing, pre-op supine, pre-op prone, as well as post-op standing postures. Pelvic parameters were measured. Spearman correlation analysis was used to determine relationships between each parameter. RESULTS: A total of 83 patients (22 males, 61females) with a mean age of 58.4 ± 9.5 years were included in this study. Pre-op standing PI was significantly lower than post-op standing PI (p = 0.004). Pre-op prone PI was significantly lower than post-op standing PI (p = 0.001). By contrast, no significant difference was observed between pre-op supine and post-op standing PI (p = 0.359) with a mean absolute difference of 2.2° ± 1.9°. Correlation analysis showed supine PI was significantly correlated with post-op standing PI (r = 0.951, p < 0.001). CONCLUSION: This study revealed the PI changed after S2AI screw fixation. The pre-op supine PI can predict post-op standing PI precisely, which facilitates to provide correction surgery strategy with a good reference for ideal sagittal alignment postoperatively.

Impact of Osteoporosis on Autogenous Bone Graft Resorption.

BACKGROUND: Osteoporosis is a common disorder that is characterized by decreased bone density and increased bone resorption. This bone resorption may affect the grafted bone during the maxillofacial reconstruction. PURPOSE: This study aimed to measure the association between osteoporosis and resorption of anterior iliac crest bone grafts used to reconstruct the atrophic anterior maxillae. STUDY DESIGN, SETTING, SAMPLE: This prospective cohort study included female patients requiring bone augmentation of the anterior maxilla. Patients with a ridge width of <4 mm and ridge height of >7 mm were enrolled in the study. Exclusion criteria were chronic use of corticosteroids or intravenous bisphosphonates, history of maxillofacial radiation therapy, current smoking, and underlying conditions contributing to bone metabolism (eg, hyperparathyroidism, chronic renal failure, and hypophosphatemia). PREDICTOR/EXPOSURE/INDEPENDENT VARIABLE: Osteoporosis status was a predictor variable. Patients were allocated to the osteoporosis or control group based on T-scores obtained by dual-energy x-ray absorptiometry. Mean T-scores ≤ -2.5 were assigned to the osteoporosis group. MAIN OUTCOME VARIABLE(S): The outcome variable was graft resorption, defined as the difference in ridge width between measurements made immediately (T1) and 6 months postoperatively (T2) using cone-beam computed tomography. COVARIATES: Patient age, preoperative (T0) bone width, and the amount of bone augmentation, defined as the differences in ridge width between measurements made preoperatively (T0) and immediately after grafting (T1), were covariates of this study. ANALYSES: Descriptive, analytic, and general linear models were computed. Statistical significance was set a P < .05. RESULTS: Thirty-two patients were included in the study (15 in the osteoporosis group and 17 in the control group). The amount of graft resorption at 6 months after grafting was 2.57 ± 0.59 mm in the osteoporosis group and 0.97 ± 0.59 mm in the control group (P < .001). A significant correlation was found between the mean T-score and graft resorption 6 months after grafting (P < .001). CONCLUSION AND RELEVANCE: A significant correlation was observed between osteoporosis and graft resorption in the anterior maxilla after 6 months.

Free iliac crest grafting technology for the management of critical-sized tibial bone defect.

OBJECTIVE: To introduce the method and experience of treating critical-sized tibial bone defect by taking large iliac crest bone graft. METHODS: From January 2020 to January 2022, iliac crest bone grafting was performed in 20 patients (10 men and 10 women) with critical-sized tibial bone defect. The mean length of bone defect was 13.59 ± 3.41. Bilateral iliac crest grafts were harvested, including the inner and outer plates of the iliac crest and iliac spine. The cortical bone screw was used to integrate two iliac bone blocks into one complex. Locking plate was used to fix the graft-host complex, supplemented with reconstruction plate to increase stability when necessary. Bone healing was evaluated by cortical bone fusion on radiographs at follow-up, iliac pain was assessed by VAS score, and lower limb function was assessed by ODI score. Complications were also taken into consideration. RESULTS: The average follow-up time was 27.4 ± 5.6 (Range 24-33 months), the mean VAS score was 8.8 ± 1.9, the mean ODI score was 11.1 ± 1.8, and the number of cortical bone fusion in the bone graft area was 3.5 ± 0.5. Satisfactory fusion was obtained in all cases of iliac bone transplant-host site. No nonunion, shift or fracture was found in all cases. No infection and bone resorption were observed that need secondary surgery. One patient had dorsiflexion weakness of the great toe. Hypoesthesia of the dorsal foot was observed in 2 patients. Ankle stiffness and edema occurred in 3 patients. Complications were significantly improved by physical therapy and rehabilitation training. CONCLUSION: For the cases of critical-sized tibial bone defect, the treatment methods are various. In this paper, we have obtained satisfactory results by using large iliac bone graft to treat bone defect. This approach can not only restore the integrity of the tibia, but also obtain good stability with internal fixation, and operation skills are more acceptable for surgeons. Therefore, it provides an alternative surgical method for clinicians.

Comparison of corticocancellous bone graft from the anterolateral metaphysis of the distal radius versus iliac crest for the treatment of unstable scaphoid nonunion with humpback deformity.

BACKGROUND: Corticocancellous bone grafting from the iliac crest is acceptable treatment for unstable scaphoid nonunion with a viable proximal pole. However, harvesting graft from the iliac crest is associated with donor site morbidity and the requirement of general anesthesia. Thus, bone grafting from the anterolateral metaphysis of the distal radius (DR) can be a treatment option. However, no study has compared the clinical effect between the two grafting techniques. METHODS: From 2014 to 2019, patients with unstable scaphoid nonunion with humpback deformity underwent corticocancellous bone grafting from the anterolateral metaphysis of the DR (group DR) or iliac crest (group IC). Humpback deformity was determined by evaluating the scapholunate angle (SLA) ≥ 60°, intrascaphoid angle (ISA) ≥ 45°, and radiolunate angle (RLA) ≥ 15° from preoperative radiographs and computed tomography scans. The SLA, ISA, and RLA served to gauge carpal alignment. The operative time, grip strength, active range of motion (ROM), the Modified Mayo Wrist score (MMWS), and Disabilities of Arm, Shoulder, and Hand (DASH) score were assessed postoperatively. RESULTS: Thirty-eight patients qualified for the study (group DR, 15; group IC, 23). Union rates did not differ by patient subset (group DR, 100%; group IC, 95.7%; P = .827), and grip strength, ROM, MWS, and DASH score were similar between groups at the last follow-up. The operative time (minutes) was significantly shorter in group DR (median, 98; quartiles, 80, 114) than in group IC (median, 125; quartiles, 105, 150, P < .001). The ISA, RLA, and SLA improved postoperatively in both groups (P < 0.001). The degree of restoring carpal alignment, as evaluated by SLA, showed superior correction capability in group DR (median, 25.3% quartiles, 21.1, 35.3, P < 0.05). Donor site complications were not significantly different between the groups. CONCLUSIONS: Corticocancellous bone graft from the anterolateral metaphysis of the DR for unstable scaphoid nonunion is associated with a shorter operation time and comparable results with that from the iliac crest in regard to union, restoration of carpal alignment, and wrist function. LEVEL OF EVIDENCE: Level III.

All-Arthroscopic Glenoid Bone Augmentation Using Iliac Crest Autograft Procedure for Recurrent Anterior Shoulder Instability: Button Fixation Is a Feasible and Satisfactory Alternative to Screw Fixation.

PURPOSE: To investigate the efficacy of all-arthroscopic glenoid bone augmentation surgery using the iliac crest autograft procedure. Furthermore, we sought to compare the clinical and radiographic outcomes of using screw versus button fixation, in patients with recurrent anterior shoulder instability. METHODS: Between 2015 and 2019, 134 shoulders with persistent instability were surgically treated with an arthroscopically placed autologous iliac crest bone graft transfer procedure. Preoperative and postoperative clinical follow-up data were evaluated using the range of motion, and the Walch-Duplay, American Shoulder and Elbow Society, and Rowe scores. Radiologic assessment on 3-dimensional computed tomography scans was performed preoperatively, immediately after surgery, as well as postoperatively, at 3 months, 6 months, 1 year, and at the final follow-up stage. Graft positions, healing, and resorption were evaluated from postoperative images. RESULTS: This study included 102 patients who underwent arthroscopic iliac crest bone grafting procedure with 2 screws fixation (n = 37; group 1) and 2 button fixation (n = 65; group 2). The mean follow-up period was 37 months. There were no significant differences between groups in terms of clinical scores, shoulder motion range, graft healing, or graft positions on computed tomography scans (P>.05). In group 1, 1 patient showed mechanical irritation and persistent pain around the screw insertion site, being treated through the arthroscopic removal of the screws. The average postoperative bony resorption percentages were 20.3% and 11.2% at 6 months, and 32.4% and 19.3% at 12 months, in group 1 and group 2, respectively. A statistically significant difference was detected between the two groups (P<.05). CONCLUSIONS: In the arthroscopic iliac crest bone grafting procedure for the treatment of chronic osseous anterior shoulder instability, excellent functional results were obtained after both button fixation and screw fixation techniques. In addition, less graft resorption and no hardware-related complications were detected with suture button fixation technique. LEVEL OF EVIDENCE: Level III, retrospective comparative therapeutic trial.

Identifying iliotibial band graft length and incision site may minimise the potential risk of harming adjacent structures: A novel approach for surgeon guidance.

PURPOSE: The Iliotibial band (ITB) is a fibrous thickening of the fascia lata originating at the iliac crest and inserting at Gerdy's tubercle on the lateral tibia. The ITB significantly contributes to lateral knee stabilisation. Due to its size, tensile strength and easy access, it is widely used in orthopaedic surgery as an autograft during reconstruction procedures. Although ITB harvesting may result in complications, such as reduced knee extension or hip flexion, no safety margins or guidelines have been proposed for the procedure. Our aim was to determine the maximal safe length of an ITB graft, that is, that does not harm the lateral collateral ligament (LCL), tensor fasciae latae (TFL), gluteus maximus (GM) or adjacent structures, and reduce the complication rate. METHODS: The study included 50 lower limbs of 25 human cadavers, previously fixed in 10% formalin solution. The inclusion criterion was the lack of visible signs of surgical interventions in the study region. Forty lower limbs were included in the study: 16 female (mean age 83.1 ± 3.4 years) and 24 male (mean age 84.2 ± 6.8 years). Dissection was performed with a previously established protocol. Morphometric measurements were then obtained twice by two researchers. RESULTS: The mean femur length was 404.8 mm [female (F) = 397.3 mm, male (M) = 409.9 mm, standard deviation (SD): F = 23.8 mm, M = 24.1 mm]. The mean ITB length was 318.9 mm (F = 309.4 mm, M = 325.2 mm, SD: F = 25.7 mm, M = 33.7 mm). Longer femurs were associated with longer ITB (p < 0.05). The mean distance from the insertion of the GM to the myofascial junction of TFL and ITB was 34.6 mm (F = 34.5 mm, M = 34.6 mm, SD: F = 3.2 mm, M = 3.3 mm). The longer femurs or ITBs demonstrated a greater distance from GM insertion to the myofascial junction of the TFL and ITB (p < 0.05). CONCLUSION: ITB grafts longer than 21 cm may contribute to the greater risk of TFL rupture. Based on simple measurements of the femur length, the surgeon may assess approximate ITB length, and thus assess the length of the maximal graft length. Moreover, to avoid harming the LCL, the incision should be performed 5 cm proximal to the articular surface of the lateral femoral condyle or 13 mm proximal to the lateral femoral epicondyle. Such preparation and preoperative planning may greatly reduce the risk of complications during ITB harvesting, while performing, for instance, the over-the-top technique for anterior cruciate ligament reconstruction in skeletally immature patients. LEVEL OF THE STUDY: Basic I.

Soft tissue movements after mandibular reconstruction using the vascularized iliac flap: patterns and predictions.

OBJECTIVES: To investigate soft-to-hard tissue response following mandibular reconstruction and to develop a predictive model for projecting soft tissue movement. MATERIALS AND METHODS: In this retrospective study, 18 patients receiving mandibular reconstruction using a vascularized iliac flap were enrolled. Various indicators for characterizing the movement of tissues were considered to identify the effective predictors for projecting soft tissue movements. Face-region-specific linear regression models for prediction were constructed and evaluated. RESULTS: The arithmetic mean of hard tissue movement in an extended area had the strongest correlation with the movement of the focal soft tissue, while the arithmetic mean in a regional area (Ram) was a more effective predictor. The linear regression model using Ram, global extrema and distances between them as the predictors performed the best in the lower margin of the face, with an average error of 1.51 ± 1.38 mm. Soft tissue movement in the alveolar process was not correlated with the existence of dentition, only can be predicted by the soft tissue movement below it. The area of the masseter was strongly correlation with Ram, but no other factors. CONCLUSIONS: An accurate prediction of soft tissue movements in the lower margin and the alveolar process of the face can be achieved by considering hard tissue and adjacent soft tissue movements. No effective predictor in the masseter area was identified. CLINICAL RELEVANCE: We investigated the relationship between hard tissue movements and the soft tissue responses in the facial area. Through building predictive models for projecting postoperative soft tissue movements, we derive insights for the aesthetic outcome of face surgeries. CLINICAL TRIAL REGISTRATION: This study was registered on the Chinese Clinical Trial Registry (registration number: ChiCTR2100054103).

A study on the morphology of iliac crest based on the objectives of jaw bone defect reconstruction.

OBJECTIVES: to understand the morphological characteristics of iliac crest and provide advice and assistance for jaw bone reconstruction with iliac bone flap by evaluating the thickness and curvature of iliac crest. MATERIALS AND METHODS: 100 patients who had taken Spiral CT of the Abdominal region before surgeries between 2020 and 2022 were included in this study. 3D reconstruction images of the iliac bones were created. 5 vertical planes perpendicular to the iliac crest were made every 2 cm along the centerline of the iliac crest (VP2 ~ VP10). On these vertical planes, 4 perpendicular lines were made every 1 cm along the long axis of the iliac crest (D1 ~ D4). The thicknesses at these sites, horizontal angle (HA) of iliac crest and the distance between inflection point and the central point of anterior superior iliac spine (DIA) were measured. RESULTS: The thickness of iliac bone decreased significantly from D1 ~ D4 on VP6 ~ VP10 and from VP2 ~ VP10 on D3 and D4 level (P<0.05). HA of iliac crests was 149.13 ± 6.92°, and DIA was 7.36 ± 1.01 cm. Iliac bone thickness, HA and DIA had very weak or weak correlation with patient's age, height and weight. CONCLUSIONS: The average thicknesses of iliac crest were decreased approximately from front to back, from top to bottom. The thickness and curvature of the iliac crest were difficult to predict by age, height and weight. CLINICAL RELEVANCE: Virtual surgical planning is recommended before jaw bone reconstruction surgery with iliac bone flap, and iliac crest process towards alveolar process might be a better choice.

Improvements in Pediatric Bone Loss Reconstruction With the Induced Membrane Technique.

BACKGROUND: The induced membrane technique is now widely used for pediatric diaphyseal bone loss due to various etiologies. Although consolidation rates remain satisfactory, complications, and healing delays may occur requiring additional procedures. We studied a series of induced membrane bone reconstructions in which the second stage included an embedded endomembranous non vascularized fibular shaft, in addition to iliac bone grafts. The purpose of this study was to analyze the results in terms of bone consolidation and complications. METHODS: This is a retrospective comparative and multicentric study of 32 children with large bone loss treated with the induced membrane reconstruction technique. Patients were divided into 2 groups according to the graft used during the second stage. The first group (G1) of 16 patients had a nonvascularized fibula embedded inside the membrane in addition with the corticocancellous grafts from the iliac crest. The second group (G2) of 16 patients underwent reconstruction using the original technique, with iliac crest graft only. RESULTS: The 2 groups were similar in terms of etiologies of bone loss and follow-up (mean: 44 mo for G1 and 49 mo for G2). Mean bone losses were 15.4 cm (range: 2 to 25; SD: 5.6) for G1 and 10.6 cm (range: 3 to 19; SD: 5.2) for G2. In the first group, all patients healed primarily, with a mean time of 5.9 months (range: 4 to 8; SD: 1.6). In the second group, 2 of 16 patients did not healed; for the others 14, healing mean time was 6.9 months (range: 3 to 12; SD: 2.7). The short-term and long-term complications rates were 38% to 19% for G1 and 50% to 31% for G2, respectively. Regarding the donor site, the fibulas reconstructed spontaneously with a mean time of 4.8 months (range: 3 to 6; SD: 1.2). CONCLUSIONS: The integration of a nonvascularized fibula during the second stage of the induced membrane technique appears to improve the consolidation rate in the pediatric population. LEVEL OF EVIDENCE: Level III-Retrospective comparative study.

Equal rates of bone healing and reduced surgical time with iliac crest allograft compared to autograft in medial opening wedge high tibial osteotomy: a randomized controlled clinical trial.

INTRODUCTION: Iliac crest autograft is frequently used to fill in bone defects after osteotomies. Nonetheless, surgery for bone autograft procurement is associated with morbidity and pain at the donor site. Alternatives to it have been explored, but there is no consensus to guide their application as a routine practice in several orthopedic procedures. Thus, this study was designed to compare the efficacy and safety between iliac crest autograft and allograft in medial opening wedge high tibial osteotomy. MATERIALS AND METHODS: Forty-seven patients with a symptomatic unilateral genu varum and an indication for high tibial osteotomy were randomly assigned to receive either autograft or allograft to fill the osteotomy site. Operative time, bone healing, and complication rates (delayed union, nonunion, superficial and deep infection, loss of correction, and hardware failure) were recorded after a one-year follow-up. Data were expressed as Mean ± Standard Deviation and considered statistically significant when p < 0.05. RESULTS: The time to radiologic union was similar between both groups (Allograft: 2.38 ± 0.97 months vs. Autograft: 2.45 ± 0.91 months; p = 0.79). Complication rates were also similar in both groups, with one infection in the allograft group and two in the autograft group, two delayed unions in the allograft group, and three in the autograft group. The operative time differed by 11 min between the groups, being lower in the allograft group (Allograft: 65.4 ± 15.1 min vs. Autograft: 76.3 ± 15.2 min; p = 0.02). CONCLUSION: Iliac crest allografts can be safely and effectively used in medial opening wedge high tibial osteotomy as it promotes the same rates of bone union as those achieved by autologous grafts, with the benefits of a shorter operative time. TRIAL REGISTRATION NUMBER: U1111-1280-0637 1 December 2022, retrospectively registered.

Deep Circumflex Iliac Artery-vascularized Iliac Bone Graft for Femoral Head Osteonecrosis: Computed Tomography Anatomical Study.

BACKGROUND: Deep circumflex iliac artery (DCIA)-vascularized iliac graft transposition is a method for treating femoral head osteonecrosis but with inconsistent efficacy. We aim to improve the method of this surgery by recommending the optimal location of the iliac pedicle to satisfy the vascular length for transposition and the blood supply of the vascularized iliac graft. METHODS: The DCIA and its surrounding tissues were assessed on computed tomography angiography images for 100 sides (left and right) of 50 patients. The length of the vascular pedicle required for transposition and the length of the pedicle at different iliac spine positions were compared. The diameter and cross-sectional area of the DCIA and the distance between the DCIA and iliac spine were measured at different points to assess blood supply. We also compared differences in sex and left-right position. RESULTS: The diameter and cross-sectional area of the DCIA gradually decreased after crossing the anterior superior iliac spine (ASIS), and it approached the iliac bone. However, when the DCIA was 4 cm behind the ASIS (54 sides, 54%), it coursed posteriorly and superiorly away from the iliac spine. The vascular length of the pedicle was insufficient to transpose the vascularized iliac graft to the desired position when it was within 1 cm of the ASIS. The vascular length requirement was satisfied, and the blood supply was sufficient when the pedicle was positioned at 2 or 3 cm. CONCLUSION: To obtain a satisfactory pedicle length and sufficient blood supply, the DCIA pedicle of the vascularized iliac graft should be placed 2 to 3 cm behind the ASIS. The dissection of DCIA has slight differences in sex and left-right position due to anatomical differences.

Multi-factor early monitoring method based on D-dimer for iliac crest flap loss.

BACKGROUND: In recent years, the utilization of autogenous vascularized iliac crest flap for repairing jaw defects has seen a significant rise. However, the visual monitoring of iliac bone flaps present challenges, frequently leading to delayed detection of flap loss. Consequently, there's a urgent need to develop effective indicators for monitoring postoperative complications in iliac crest flaps. METHODS: A retrospective analysis was conducted on 160 patients who underwent vascularized iliac crest flap transplantation for jawbone reconstruction from January 2020 to December 2022. We investigated the changes in D-dimer levels among patients with or without postoperative complications. Additionally, multivariable logistic regression analysis was performed to explore potential individual risk factors, including surgical duration, age, pathology type, absolute and relative D-dimer levels, and gender, culminating in the development of a nomogram. RESULTS: On the first day following surgery, patients who experienced thrombosis exhibited a substantial increase in plasma D-dimer levels, reaching 3.75 mg/L, 13.84 times higher than the baseline. This difference was statistically significant (P < 0.05) compared to patients without postoperative complications. Furthermore, the nomogram we have developed and validated effectively predicts venous thrombosis, assigning individual risk scores to patients. This predictive tool was assessed in both training and validation cohorts, achieving areas under the curve (AUC) of 0.630 and 0.600, with the 95% confidence intervals of 0.452-0.807 and 0.243-0.957, respectively. CONCLUSIONS: Our study illustrates that postoperative plasma D-dimer levels can serve as a sensitive biomarker for monitoring thrombosis-induced flap loss. Moreover, we have developed a novel prediction model that integrates multiple factors, thereby enhancing the accuracy of early identification of patients at risk of thrombosis-associated flap loss. This advancement contributes to improving the overall management and outcomes of such procedures.

Quantitative Volumetric Measurements of Bone Grafting Sites Within the Lower Extremity on Computed Tomography Scans.

The anterior iliac crest is one of the most used options; however, pain and other complications have been reported. Other options for bone harvest in the lower extremity, such as the proximal tibia and calcaneus, can be useful sites for bone grafting. Computed tomography angiography images of the lower extremity were analyzed using 3-D Slicer™ medical imaging software, creating an advanced 3-dimensional model. Bone volume (cm3) and bone mineral density (Hounsfield units) were measured from the cancellous bone in the anterior iliac crest, posterior iliac crest, proximal tibia, and the calcaneus. Fifteen studies were included. The total volume measured it was of 61.88 ± 14.15 cm3, 19.35 ± 4.16 cm3, 32.48 ± 7.49 cm3, 26.40 ± 7.18 cm3, for the proximal tibia, anterior and posterior iliac crest, and calcaneus, respectively. Regarding Hounsfield units, the densities were 116 ± 58.77, 232.4 ± 68.65, 214.4 ± 74.45, 170.5 ± 52.32, for proximal tibia, anterior and posterior iliac crest, and calcaneus. The intraclass correlation coefficients were in average >0.94. In conclusion, the proximal tibia has more cancellous bone than the anterior and posterior iliac crest. The calcaneus has more cancellous bone than the anterior iliac crest. Bone mineral density was highest in the anterior iliac crest and in proximal tibia was the lowest value.

Computerized surgical navigation resection of pelvic region simulated bone tumors using skin fiducial marker registration: an in vitro cadaveric study.

INTRODUCTION: Computerized surgical navigation system guidance can improve bone tumor surgical resection accuracy. This study compared the 10-mm planned resection margin agreement between simulated pelvic-region bone tumors (SPBT) resected using either skin fiducial markers or Kirschner (K)-wires inserted directly into osseous landmarks with navigational system registration under direct observation. We hypothesized that skin fiducial markers would display similar resection margin accuracy. METHODS: Six cadaveric pelvises had one SPBT implanted into each supra-acetabular region. At the left hemi-pelvis, the skin fiducial marker group had guidance from markers placed over the pubic tubercle, the anterior superior iliac spine, the central and more posterior iliac crest, and the greater trochanter (5 markers). At the right hemi-pelvis, the K-wire group had guidance from 1.4-mm-diameter wires inserted into the pubic tubercle, and 3 inserted along the iliac crest (4 K-wires). The senior author, a fellowship-trained surgeon performed "en bloc" SPBT resections. The primary investigator, blinded to group assignment, measured actual resection margins. RESULTS: Twenty of 22 resection margins (91%) in the skin fiducial marker group were within the Bland-Altman plot 95% confidence interval for actual-planned margin mean difference (mean = -0.23 mm; 95% confidence intervals = 2.8 mm, - 3.3 mm). Twenty-one of 22 resection margins (95%) in the K-wire group were within the 95% confidence interval of actual-planned margin mean difference (mean = 0.26 mm; 95% confidence intervals = 1.7 mm, - 1.1 mm). CONCLUSION: Pelvic bone tumor resection with navigational guidance from skin fiducial markers placed over osseous landmarks provided similar accuracy to K-wires inserted into osseous landmarks. Further in vitro studies with different SPBT dimensions/locations and clinical studies will better delineate use efficacy.

Utilizing robotic-assisted navigation for pelvic instrumentation in pediatric patients with neuromuscular scoliosis: a technical note and case series.

Pelvic fixation is commonly used in correcting pelvic obliquity in pediatric patients with neuromuscular scoliosis and in preserving stability in adult patients with lumbosacral spondylolisthesis or instances of traumatic or osteoporotic fracture. S2-alar-iliac screws are commonly used in this role and have been proposed to reduce implant prominence when compared to traditional pelvic fusion utilizing iliac screws. The aim of this technical note is to describe a technique for robotically navigated placement of S2-alar-iliac screws in pediatric patients with neuromuscular scoliosis, which (a) minimizes the significant exposure needed to identify a bony start point, (b) aids in instrumenting the irregular anatomy often found in patients with neuromuscular scoliosis, and (c) allows for greater precision than traditional open or fluoroscopic techniques. We present five cases that underwent posterior spinal fusion to the pelvis with this technique that demonstrate the safety and efficacy of this procedure.

Effect of different lumbar-iliac fixation and sacral slope for Tile C1.3 pelvic fractures: a biomechanical study.

BACKGROUND: Lumbar-iliac fixation (LIF) is a common treatment for Tile C1.3 pelvic fractures, but different techniques, including L4-L5/L5 unilateral LIF (L4-L5/L5 ULIF), bilateral LIF (BLIF), and L4-L5/L5 triangular osteosynthesis (L4-L5/L5 TOS), still lack biomechanical evaluation. The sacral slope (SS) is key to the vertical shear of the sacrum but has not been investigated for its biomechanical role in lumbar-iliac fixation. The aim of this study is to evaluate the biomechanical effects of different LIF and SS on Tile C1.3 pelvic fracture under two-legged standing load in human cadavers. METHODS: Eight male fresh-frozen human lumbar-pelvic specimens were used in this study. Compressive force of 500 N was applied to the L4 vertebrae in the two-legged standing position of the pelvis. The Tile C1.3 pelvic fracture was prepared, and the posterior pelvic ring was fixed with L5 ULIF, L4-L5 ULIF, L5 TOS, L4-L5 TOS, and L4-L5 BLIF, respectively. Displacement and rotation of the anterior S1 foramen at 30° and 40° sacral slope (SS) were analyzed. RESULTS: The displacement of L4-L5/L5 TOS in the left-right and vertical direction, total displacement, and rotation in lateral bending decreased significantly, which is more pronounced at 40° SS. The difference in stability between L4-L5 and L5 ULIF was not significant. BLIF significantly limited left-right displacement. The ULIF vertical displacement at 40° SS was significantly higher than that at 30° SS. CONCLUSIONS: This study developed an in vitro two-legged standing pelvic model and demonstrated that TOS enhanced pelvic stability in the coronal plane and cephalad-caudal direction, and BLIF enhanced stability in the left-right direction. L4-L5 ULIF did not further improve the immediate stability, whereas TOS is required to increase the vertical stability at greater SS.