Pelvic Tumor Surgery Research Articles

Evaluation of the accuracy of 3D-printed patient-specific osteotomy templates in pelvic tumor resection and reconstruction

PurposeThe treatment of pelvic tumors has been widely recognized as challenging. Patient-specific osteotomy templates were designed and generated for precise surgery, based on tumor fusion images and 3D printing technology. This study aimed to investigate the accuracy of patient-specific osteotomy templates for the resection of pelvic tumors.MethodsFrom April 2014 to August 2023, 27 patients with pelvic tumors at our hospital were enrolled in this study. All patients underwent CT and enhanced MRI before surgery to develop a 3D preoperative imaging plan model for pelvic tumors based on tumor fusion images. For patients in the intraoperative use of osteotomy templates group, we designed and generated patient-specific osteotomy templates for intraoperative assisted tumor resection. For patients in the no use of osteotomy templates group, surgeons performed tumor resection according to conventional techniques. All patients were followed up to obtain postoperative CT images of the pelvis. Preoperative planning osteotomy surface and intraoperative actual osteotomy surface were obtained by means of the image registration technique. Then, the distance deviation and angle deviation between the two surfaces were compared to assess the accuracy of surgery.ResultsSurgery was successfully completed in 27 patients, and all specimens were obtained for tumor-free resection margins. The median of intraoperative bleeding was 2350(1425 ∼ 3000) ml in the intraoperative use of osteotomy templates group and 4500(3150 ∼ 5200)ml in the no use of osteotomy templates group. p-value was 0.016. The median angular deviation of the actual osteotomy surfaces from the planned osteotomy surfaces was 5.02 (2.84 ∼ 7.37)° in the intraoperative use of osteotomy templates group, and 7.17 (4.49 ∼ 11.96)° in the no use of osteotomy templates group. p-value was 0.044. The absolute mean distance deviation between the two surfaces was 4.90 ± 3.01 mm in the intraoperative use of osteotomy templates group, and 7.21 ± 3.89 mm in the no use of osteotomy templates group. p-value was 0.038.Conclusions3D-printed patient-specific osteotomy templates can be accurately customized based on preoperative tumor fusion image, which can help improve the precision of pelvic tumor surgery.

Staged operations of acquired lymphangiectasia of the vulva: 10 cases clinical analysis

Objective: To investigate the characteristics, diagnosis and therapeutic effect of acquired lymphangiectasia of the vulva (ALV). Methods: A retrospective analysis of clinicopathological and follow-up data was conducted on the patients treated in Capital Medical University Affiliated Beijing Shijitan Hospital due to female ALV from July 2009 to July 2023. The patients who completed the staged operations [partial labiectomy and reconstruction + thoracic ductplasty and (or) perineal lymphovenous anastomosis] were included in the study and followed up. The improvement of perineal swelling, blister range, fluid leakage volume and frequency were evaluated through outpatient visits by the symptom rating scale of ALV (hereinafter referred to as the symptom rating scale) before and after surgery. Results: A total of 48 patients were treated due to ALV from July 2009 to July 2023, of which 98% (47/48) were postoperative pelvic malignant tumors and 94% (45/48) had a history of radiotherapy. A total of 10 patients with ALV who completed the staged operations were included in this study. (1) Clinical characteristics and diagnosis: 10 patients had a median age of 60 years old (50, 63 years old ). The median duration from cervical cancer surgery and radiation therapy to vulvar swelling was 1.5 years (0.0, 2.0 years), and the median duration from vulvar swelling to blister formation and leakage was 0.0 years (0.0, 4.8 years). Seven patients (7/10) had a history of recurrent erysipelas; 7 patients (7/10) had the most severe symptom (widespread blisters, persistent fluid leakage, and large amount of fluid leakage); noncontrast magnetic resonance lymphography (NCMRL) showed edema signals in the perineal region of all the patients, and increase of agent in the perineal region was observed in lymphoscintigram (LS). (2) Surgical treatment and postoperative pathological examination: of the 10 ALV patients who completed staged surgical treatment, 6 cases (6/10) were diagnosed with thoracic duct outlet obstruction and underwent thoracic ductplasty and partial labiectomy and reconstruction. Perineal lymphovenous anastomosis and partial labiectomy and reconstruction were performed in 4 cases (4/10) without thoracic duct outlet obstruction. Postoperative routine pathological examination of 10 patients (10/10) showed dermal papilla lymphangiectasia. Immunohistochemical tests were performed on 5 patients, all of which were positive for D2-40 and negative for CD34. (3) Efficacy: 8 patients completed the postoperative follow-up, and the median follow-up time was 31.0 months (17.5, 78.3 months). The perineal swelling and the blister fluid leakage were all significantly improved after the staged operations. All indexes of the symptom rating scale, including the degree of perineal swelling, blister range, fluid leakage volume and frequency, were significantly improved in 8 follow-up patients, and 3 (3/8) of them were cured; the median symptom score decreased significantly from 11.0 before surgery to 3.0 after surgery (P<0.001). The incidence of erysipelas was significantly reduced from 7/10 before surgery to 2/8 after surgery (P=0.035). Conclusions: The main causes of female ALV are pelvic tumor surgery and radiotherapy. The clinical diagnosis is made from relevant medical history, clinical manifestations, LS and magnetic resonance imaging. The diagnosis is confirmed by histopathological findings. Pathological results show lymphangiectasia in the dermal papilla, and immunohistochemical staining show positive for D2-40 and negative for CD34. The effect of staged surgery on ALV is remarkable and even cured, and could effectively reduce the incidence of erysipelas.

How Might the Number of Lymph Nodes Removed during RARP Impact the Postoperative Outcomes?

Introduction: Symptomatic lymphocele remains a relevant complication after pelvic tumor surgery. This study aims to investigate how the number of lymph nodes removed may influence postoperative outcomes and if it increases the probability of detecting lymph node metastasis. Methods: The study included 500 patients who underwent RARP including lymphadenectomy performed by a single surgeon. Patients were divided into two groups: group 1 consisted of 308 patients with 20 or fewer lymph nodes removed (mean 15), while group 2 had 192 patients with over 20 nodes removed (mean 27). Perioperative data were analyzed, and postoperative outcomes were compared between groups. Results: Overall, lymph node metastasis was detected in 17.8% of men. In detail, out of 19.6 lymph nodes removed, an average of 3.14 lymph nodes per patient showed metastasis, with a slightly higher incidence of 19.7% in group 2 compared to 16.5% in group 1, though not statistically significant (p = 0.175). The number of lymph node metastases was significantly higher in group 2 patients (3.47) versus group 1 (2.37) (p = 0.048). All complications except symptomatic lymphoceles (p = 0.004) were not significantly different between groups. Univariate linear regression analysis revealed no correlation between the number of removed lymph nodes and symptomatic lymphocele. However, it did correlate with catheter days and readmissions. Conclusion: A correlation may exist between the number of lymph nodes removed during RARP and an increased incidence of complications, particularly symptomatic lymphocele. A more extensive PLND may result in prolonged catheter days and increased readmissions. With the increased extent of pelvic lymphadenectomy, the probability of detecting lymphogenic metastasis rises. The diagnostic value of PLND is well established. Further randomized trials are needed to weigh its necessity and extent.

Classification system of radical surgery for rectal cancer based on membrane anatomy

Because the classification system of radical surgery for rectal cancer has not been established, it is impossible to select the appropriate surgical method according to the clinical stage of the tumor. In this paper, we explained the theory of " four fasciae and three spaces " of pelvic membrane anatomy and then combined this theory with the membrane anatomical basis of Querleu-Morrow classification for radical cervical cancer resection. Based on this theory and the membrane anatomy of Querleu-Morrow classification of radical cervical cancer resection, we proposed a new classification system of radical rectal cancer surgery based on membrane anatomy according to the lateral lymph node dissection range of the rectum. This system classifies the surgery into four types (ABCD) and defines corresponding subtypes based on whether the autonomic nerve was preserved. Among them, type A surgery is total mesorectal excision (TME) with urogenital fascia preservation, type B surgery is classical TME, type C surgery is extended TME, and type D surgery is lateral extended resection. This classification system unifies the anatomical terminology of the pelvic membrane, validates the feasibility of using the " four fasciae and three fascial spaces " theory to classify rectal cancer surgery, and lays the theoretical foundation for the future development of a unified and standardized classification of radical pelvic tumor surgery.

Differences in hip musculoskeletal loads between limbs during daily activities in patients with 3D-printed hemipelvic reconstructions following tumor surgery

BackgroundAnatomical custom-made prostheses, thanks to computer-aided design and 3D-printing technology, help improve osseointegration and reduce mechanical complications in bone reconstructions following bone tumors. A recent quantitative analysis of long-term recovery in patients with 3D-printed reconstructions following pelvic tumor surgery showed asymmetries in ground reaction forces between limbs during different motor activities, while standing very good motor performance and quality of life. Research questionWe analyzed hip contact forces and muscle forces in that cohort of six patients with an innovative custom-made reconstruction of the hemipelvis, and we tested the hypothesis that asymmetries in ground reaction forces would result in more marked differences in musculoskeletal forces. MethodsState-of-the-art musculoskeletal modeling in an optimization-based inverse-dynamics workflow was used to calculate hip contact forces and muscle forces during five motor activities, and the differences between limbs were statistically evaluated across the motor activity cycles and on the force peaks. ResultsThe musculoskeletal loads were found to be not symmetric, as hip loads were generally higher in the contralateral limb. We found significant differences in considerable portions of the motor activities cycles except squat, load symmetry indices indicating a load increase (median up to 25%) on the contralateral limb, especially during stair descent and chair rise/sit, and significantly higher values in the contralateral limb at force peaks. SignificanceWe confirmed the hypothesis that residual asymmetries found in ground reaction forces were amplified when hip musculoskeletal loads were investigated, reflecting a shift of the loads toward the intact limb. Despite the general trend of higher loads found in the contralateral hip, this cannot be considered a risk of overloading, as both hips supported loads in a physiological range or lower, indicating a likely optimal recovery.

Trajectory of worst pain within the first two weeks following pelvic and sacral tumor surgery and long-term outcome: a pilot observational prospective cohort study

BackgroundPain management after pelvic and sacral tumor surgery is challenging and requires a multidisciplinary and multimodal approach. Few data on postoperative pain trajectories have been reported after pelvic and sacral tumor surgery. The aim of this pilot study was to determine pain trajectories within the first 2 weeks after surgery and explore the impact on long-term pain outcomes.MethodsPatients scheduled for pelvic and sacral tumor surgery were prospectively recruited. Worst/average pain scores were evaluated postoperatively using questions adapted from the Revised American Pain Society Patient Outcome Questionnaire (APS-POQ-R) until pain resolution was reached or up to 6 months after surgery. Pain trajectories over the first 2 weeks were compared using the k-means clustering algorithm. Whether pain trajectories were associated with long-term pain resolution and opioid cessation was assessed using Cox regression analysis.ResultsA total of 59 patients were included. Two distinct groups of trajectories for worst and average pain scores over the first 2 weeks were generated. The median pain duration in the high vs low pain group was 120.0 (95% CI [25.0, 215.0]) days vs 60.0 (95% CI [38.6, 81.4]) days (log rank p = 0.037). The median time to opioid cessation in the high vs low pain group was 60.0 (95% CI [30.0, 90.0]) days vs 7.0 (95% CI [4.7, 9.3]) days (log rank p < 0.001). After adjusting for patient and surgical factors, the high pain group was independently associated with prolonged opioid cessation (hazard ratio [HR] 2.423, 95% CI [1.254, 4.681], p = 0.008) but not pain resolution (HR 1.557, 95% CI [0.748, 3.243], p = 0.237).ConclusionsPostoperative pain is a significant problem among patients undergoing pelvic and sacral tumor surgery. High pain trajectories during the first 2 weeks after surgery were associated with delayed opioid cessation. Research is needed to explore interventions targeting pain trajectories and long-term pain outcomes.Trial registrationThe trial was registered at ClinicalTrials.gov (NCT03926858, 25/04/2019).

ASO Author Reflections: Long-Term Perspective in Choosing Between Carbon-Ion Radiotherapy and Surgery for Malignant Pelvic Bone Tumors.

ASO Author Reflections: Long-Term Perspective in Choosing Between Carbon-Ion Radiotherapy and Surgery for Malignant Pelvic Bone Tumors.

Pelvic sarcoma surgery (literature review)

for management and to achieve good functional results. About 10–15 % of all primary malignant tumors are localized inthe pelvic bones. Objective. To perform a literature review to identify key historical scientific and practical achievements thathave influenced the stages of the development of pelvic sarcoma surgery. Methods. To study the publications at Google searchengine, electronic databases PubMed, Google Scholar, archives of specialized journals and other sources of scientific and medical information. Results. The history of the development and improvement of the treatment pelvic bone tumor patients has more than 125 years. Important stages in the formation of this oncologic orthopedics area are improvement of anesthesia and resuscitation methods, study and understanding of mesenchymal tumors biology, modernization of neoplastic imaging methods, development of polychemotherapy (PCT) and radiotherapy protocols, the possibility of 3D-modeling of surgical interventions, creation of various artificial and biomaterials for bone defects replacement, critical view on oncological, functional outcomes and complications assessment. Today, the majority of patients with local pelvic bone sarcomas have the opportunity to perform limb salvage surgery. However, the issue of reconstruction of pelvic bone defects after massive resections remains incompletely understood. Reconstruction often provides a better functional result at a price of greater complications, and it influences the choice of the applied method. Conclusions. Despite of significant advances that was achieved since the first attempted of hemipelvectomy in 1891, a number of problematic issues in pelvic tumor surgery remains unresolved. Therefore, the search for a more adequate, less traumatic and functionally beneficial method of postresection pelvic bone defects reconstruction using biological materials and various types of custom-made/serial prosthetics keeps going, especially when the acetabulum is involved.

FEATURES OF REPLACEMENT OF EXTENSIVE POST-RESECTION BONE DEFECTS IN PELVIC AND SACRAL TUMORS

Purpose of the study . To represent the results of a two-stage surgical treatment in patients with extensive pelvic bone defects. Materials and methods . Data on 7 patients who underwent surgery for pelvic and sacrum tumors at the National Medical Research Centre for Oncology from 2016 up to 2020 are presented. The average age of the patients was 36 years. Patients with massive tumors that required a major resection of the posterior pelvis and the formation of an extensive bone defect requiring reconstruction with massive allografts and implants were selected for the study. 5 patients underwent different variations of sacrectomies with the resection of the iliac bones; 2 patients – interiliac-abdominal resections. For all these patients, surgical treatment was split into 2 stages. Results . At the first stage we performed: 5 surgical interventions (total or extended sacrectomy at L5–S1 with lumbar-iliac bilateral stabilization with an 8‑screw pedicle system) in patients with sacral tumors. In 2 cases, an interilio-abdominal resection with the defect replacement with cement articulating spacer. Intraoperative blood loss on average was 1.8L. We used autohemotransfusion to compensate the intraoperative blood loss. The 2nd (reconstructive) stage was completed on average after 3 months. The reconstructive stage was not accompanied by major trauma in all patients. The average blood loss was approximately 800 ml. There were no complications after the reconstructive surgical stage. Conclusion . The described two-stage technique allowed to avoid severe infectious complications requiring removal of implants and grafts in all patients. Adequate spinal pelvic stabilization and/or spacing of the defect contributed to early functional rehabilitation of patients and the continuation of adequate adjuvant therapy in the interstage period. The delaying of the reconstruction allowed to reduce the duration and invasiveness of the main intervention without affecting the final result of treatment.

Preoperative arterial embolization and wound complications after resection of malignant bone tumor in the pelvis: a nationwide database study.

Massive intraoperative blood loss is common in pelvic malignant bone tumor surgery, and preoperative arterial embolization may be used in selected cases. Preoperative arterial embolization reportedly increases wound complications in pelvic fracture surgery, but little evidence is available regarding pelvic bone tumor surgery. Using a Japanese nationwide database (Diagnosis Procedure Combination database), we searched for patients who underwent pelvic malignant bone tumor surgery between July 2010 and March 2018. The primary endpoint was wound complications, defined as any wound requiring re-operation, negative pressure wound therapy or both. Univariate analyses (the chi-squared test for categorical variables, the unpaired t-test for continuous variables) and multivariate logistic regression analyses were performed to examine the association between preoperative arterial embolization and wound complications. Among the 266 eligible patients, 43 (16%, 43/266) underwent embolization and 69 (26%, 69/266) developed wound complications. In the univariate analyses, preoperative arterial embolization (P<0.001), duration of anesthesia (P<0.001), the volume of blood transfusion (P<0.001) and duration of indwelling drain tube (P<0.001) were associated with wound complications. In the multivariate logistic regression analysis, preoperative arterial embolization was significantly associated with wound complications (odds ratio, 3.92; 95% confidence interval, 1.80-8.56; P=0.001). Preoperative arterial embolization may be associated with increased wound complications after pelvic malignant tumor surgery.

Custom-made 3D-Printed Prosthesis in Periacetabular Resections Through a Novel Ileo-adductor Approach.

Resection of sarcomas around the acetabulum presents major challenges. The resulting bone effect can be reconstructed with personalized custom-made prostheses. Patient-specific instruments (PSIs) have been demonstrated to be of added value for bone-cutting accuracy, and they may improve pelvic surgery. The authors describe a novel ileo-adductor approach for pelvic tumor surgery and report the preliminary results of 5 reconstructions using custom 3D-printed prostheses associated with PSI surgical guides. This combined technique allows an optimal restoration of the anatomy with reduced surgical time and reduced postoperative complications such as infections and wound healing problems. [Orthopedics. 2022;45(2):e110-e114.].

Computer-Assisted Surgical Navigation for Primary and Metastatic Bone Malignancy of the Pelvis: Current Evidence and Future Directions.

Computer-assisted navigation and robotic surgery have gained popularity in the treatment of pelvic bone malignancies, given the complexity of the bony pelvis, the proximity of numerous vital structures, and the historical challenges of pelvic bone tumor surgery. Initial interest was on enhancing the accuracy in sarcoma resection by improving the quality of surgical margins and decreasing the incidence of local recurrences. Several studies have shown an association between intraoperative navigation and increased incidence of negative margin bone resection, but long-term outcomes of navigation in pelvic bone tumor resection have yet to be established. Historically, mechanical stabilization of pelvic bone metastases has been limited to Harrington-type total hip arthroplasty for disabling periacetabular disease, but more recently, computer-assisted surgery has been employed for minimally invasive percutaneous fixation and stabilization; although still in its incipient stages, this procedure is potentially appealing for treating patients with bone metastases to the pelvis. The authors review the literature on navigation for the treatment of primary and metastatic tumors of the pelvic bone and discuss the best practices and limitations of these techniques.

Efficacy and safety of prophylactic intravenous administration of tranexamic acid in abdominal aorta balloon-assisted pelvic tumor surgery

Objective: To investigate the efficacy and safety of prophylactic intravenous (IV) administration of tranexamic acid (TXA) in abdominal aorta balloon-assisted pelvic tumor surgery. Methods: The data of patients who underwent abdominal aorta balloon-assisted pelvic tumor surgery in Peking University People's Hospital from January 1, 2015 to December 31, 2019 were retrospectively collected. According to whether receiving the prophylactic use of TXA, the patients were divided into two groups: TXA group and control group. After propensity score matching based on age, gender and surgeon, 51 patients in TXA group and 51 patients in control group were allocated. The baseline, intraoperative and postoperative clinical data of the two groups were compared to explore the efficacy and safety of TXA. Results: A total of 525 cases undergoing abdominal aorta balloon-assisted pelvic surgery were enrolled from 2015 to 2019, of which 51 cases received prophylactic use of TXA, with a utilization rate of 9.7%. There were no significant differences in age [(40.7±15.1) years vs (38.2±14.5) years, P=0.393], gender (male: 51.0% vs 49.0%, P=0.843), body weight, body mass index (BMI), complications, American Society of Anesthesiologists (ASA) classification, hemoglobin, hemocrit (Hct), platelet, coagulation function-related indexes and tumor pathological types between the two groups (all P>0.05). Likewise, there were no significant differences in operation time, anesthesia time, cumulative time of balloon occlusion, intraoperative blood loss, intravenous fluid volume and blood transfusion volume between the two groups (all P>0.05). Additionally, there were no significant differences in postoperative ICU admission rate and length of hospital stay between the two groups (all P>0.05), and no venous thromboembolism (VTE) or death was reported. Compared with the control group, the rate of blood transfusion at 24 hours after operation in the TXA group was lower (41.2% vs 70.6%, P=0.003). The level of fibrinogen degradation products was lower [10.4 (6.1, 22.6) mg/L vs 13.2 (7.0, 24.7) mg/L], but the difference was not statistically significant (P=0.326). Conclusions: Prophylactic IV use of TXA does not reduce intraoperative bleeding in abdominal aorta balloon-assisted pelvic tumor surgery, but can decrease the rate of postoperative blood transfusion. No increased risk of postoperative TXA-related VTE was observed.

Intraoperative balloon occlusion of the aorta for blood management in sacral and pelvic tumor resection: A systematic review and meta-analysis

BackgroundNeoplasms of the sacrum and pelvis are challenging to manage due to their complex vascularity and size and are at high risk of bleeding during resection. Intra-aortic balloon occlusion (IABO) has been used in trauma to control massive blood loss, but its efficacy and safety in oncologic sacral and pelvic surgery are unknown. The primary objective of this systematic review and meta-analysis was to assess the effectiveness of IABO in providing hemorrhage control during resection of sacral and pelvic tumors. MethodsThis PROSPERO pre-registered study meta-analyzed all studies reporting on the use of IABO in the setting of pelvic and sacral tumour resection, in accordance with the PRISMA guidelines. The primary outcome of the meta-analysis was intraoperative blood loss, with secondary outcomes consisting of transfusion volume, post-operative blood loss, operative time, complication rate, and mortality. ResultsAcross studies, IABO was associated with a large, significant reduction in intraoperative blood loss (SMD -0.81, 95% CI -1.01 to −0.60, P < 0.0001) and transfused red blood cell volume (SMD 0.92, 95% CI -1.30 to −0.53, P < 0.0001). Two studies reported that complication rates were comparable between patients receiving IABO and patient receiving conventional surgery (Odds ratio = 1.29, 95% CI: 0.59 to 2.83, P = 0.52). All studies descriptively reported improved visualization of the operative field with IABO. ConclusionsOur findings demonstrated that IABO is an effective technique to decrease blood loss and transfusion requirements during sacral and pelvic tumor surgery. Future clinical trials should be conducted to establish the safety of this method and explore potential contraindications.

Accumulative occlusion time correlates with postoperative pulmonary complications in patients undergoing pelvic and sacrum tumor resection assisted by abdominal aortic balloon occlusion: a retrospective cohort study

BackgroundPostoperative pulmonary complications (PPCs) seems to be high in patients undergoing pelvic and sacrum tumor resection assisted by abdominal aortic balloon occlusion. We hypothesized that the accumulative occlusion time (AOT) of the abdominal aortic balloon may be predictive of PPCs. The objective of the study was to identify the influence of AOT on PPCs.MethodsRetrospectively analyzed perioperative factors of 584 patients who underwent pelvic and sacrum tumor resection assisted by abdominal aortic balloon occlusion in our hospital from January 1, 2016 to December 31, 2018. PPCs including suspected pulmonary infection, atelectasis, pulmonary edema, pleural effusion, respiratory failure were clinically diagnosed. Perioperative parameters among patients with and without PPCs were compared. A receiver operating characteristic (ROC) analysis was conducted to evaluate the discriminative power of AOT with regard to PPCs. A multivariate logistic-regression model was finally established to identify independent risk factors for PPCs.ResultsThe incidence of PPCs was 15.6% (91 patients). The median AOT in PPCs group was significantly higher than that in non-PPCs group (P < 0.001). The hospital stay was significantly prolonged in PPCs group (P < 0.001). The ROC analysis showed an AOT of 119 min as the threshold value at which the joint sensitivity (88.60%) and specificity (31.87%) was maximal. Finally, AOT ≥ 119 min (P = 0.046; odds ratio (OR) = 2.074), age (P < 0.001; OR = 1.032), ASA grade III (P = 0.015; OR = 3.264), and estimated blood loss (P = 0.022; OR = 1.235) were independent risk factors of PPCs by multivariate logistic regression analysis.ConclusionThe incidence of PPCs in patients undergoing the pelvic and sacrum tumor surgery assisted by abdominal aortic balloon occlusion was 15.6%. AOT ≥ 119 min was an independent predictor for PPCs. Surgeons should strive to minimize the AOT within 2 h.

The application of 3D-printing technology in pelvic bone tumor surgery

BackgroundThree-dimensional (3D)-printing technology provides an advanced approach to pelvic bone tumor resection and reconstruction. However, only a few cases of pelvic bone tumor surgery using 3D-printing have been reported due to limited time since the introduction of the new implant. This study introduces pelvic bone tumor surgeries using 3D-printed bone-cutting guides and implants. MethodsThis single-center retrospective review included 12 patients who underwent malignant pelvic bone tumor surgeries using a 3D-printed bone-cutting guide and/or implant. Clinical information was collected regarding patient demographics, tumor characteristics, pathologic diagnosis, surgery details, and functional recovery. ResultsType I internal hemipelvectomy was performed using 3D-printed bone-cutting guides for 4 patients that underwent cavitary bone tumor resection of the ilium. For 3 of these 4 patients, cavitary bone defects were filled with structural allobone graft precisely trimmed by the 3D-printed allograft-shaping guide (n = 1) and 3D-printed mesh-style titanium spacer (n = 2). For type II and III areas, one and two patients, respectively, underwent 3D-printing-assisted surgery. Five patients underwent type I, II, and III pelvic resection using 3D-printed cutting guides and reconstruction with 3D-printed implants. In all patients, independent gait was recovered except for a patient who underwent hindquarter amputation 4 months postoperatively because of local recurrence. ConclusionsThis study provides preliminary, short-term data on the efficacy and safety of pelvic bone tumor surgery using 3D-printing.

The pararectus approach\u2014a versatile option in pelvic musculoskeletal tumor surgery

BackgroundPelvic tumors are usually resected through the utilitarian pelvic incision, an extended ilioinguinal/iliofemoral approach. The pararectus approach, an intrapelvic anatomical approach with extraperitoneal access to the pelvis, has been established previously for the treatment of pelvic and acetabular fractures. However, it has not been used to address pelvic tumors. The study aimed at investigating the feasibility of this approach for pelvic tumor surgery and the possibilities of combining this approach with standard approaches to the hip joint.MethodsThirteen patients that underwent pelvic tumor resections were retrospectively reviewed. Tumor resections were performed through the pararectus (n = 10) or extended pararectus approach (n = 3). In six of those cases, the pararectus approach was combined with extrapelvic approaches including the modified Gibson (n = 4), the Kocher-Langenbeck (n = 1), and the trochanteric flip approach (n = 1). The mean follow-up was 32.6 ± 9.1 months.ResultsIn all cases, the tumor resections were carried out according to the preoperative plan. In seven of 13 cases, wide resections were performed; six of 13 cases were planned close resections. Four cases of major complications were observed (vascular injury, deep infection, iliac vein thrombosis, total hip arthroplasty dislocation). Minor complications were observed in two cases. One tumor recurred locally. At the final follow-up, 10 patients were alive, eight of those without evidence of disease.ConclusionThe study demonstrated the suitability of the pararectus approach for pelvic tumor resections. The possibility to combine the approach with standard approaches to the hip joint allowed for single-stage reconstructions of the pelvis and the hip joint without sacrificing surgical margins and function. The pararectus approach is a versatile option adding to the established approaches for musculoskeletal tumor surgery of the pelvis.

Study on the application of fine anesthesia management in pelvic tumor surgery

Objective To study the clinical efficacy and safety of fine anesthetic management in general anesthesia for pelvic tumor patients who undergoing open surgery. Methods A total of 96 elective patients with pelvic tumors who need general anesthesia were selected. ASA Ⅰ-Ⅱ level was randomly divided into two groups: the experience group (group B, the control group) and the refined anesthesia management group (group B, the observation group), with 48 cases in each group. Patients in group B accept anesthesia management based on clinical experience of anesthesiologists, patients in group B accept anesthesia management based on index of instruments and equipment (including the guidance of anesthesia depth monitoring and closed-loop muscle relaxant injection system, heart function monitor). Time points setting as follows: 3 min after the Narcotrend (NT) numerical data in the room (T0), immediately after intubation (T1), into the abdomen (T2), resected immediately (T3), closing abdomen (T4), skin suture (T5), tracheal extubation (T6), consciousness recovery (T7), out of room (T8). MAP, HR and RR were recorded. Also, index as follows was recorded: SpO2, Narcotrend stage (NTS), Narcotrend index(NTI), myocutaneous count, train-of-four(TOF), stroke volume variation (SVV), anesthetic dosage, fluid volume, urine volume, intubation (according to the Copper score method), recovery time (stopping to call every time), extubation time (between withdrawal and extubation time), sedation score at leaving operation room, the adverse reactions, the time of stay in the ICU and the time from operation to discharge. Results Compared with group A, MAP and HR in group B were low at T1-T8 time (P<0.05). NTS was high in phase D1-E2 (P<0.05). In group B, the dosage of midazolam (P<0.05), propofol, sufentanil, remifentanil and atracurium sulfonate were small (P<0.05). Compared with group A, the total amount of group B was low (P<0.05). The time of awakening, the time of extubation was short. The Copper score was high. The Ramsay score was low (P<0.05). The adverse reactions and complications in group B were less than numbers in group A. The stay time in the guardianship and the time of discharge of patients in group B were shorter than the time in patients of group A (P<0.05). Conclusions The fine anesthesia management makes smooth induction and maintenance, timely and complete awakening, fewer adverse reactions and complications, better postoperative outcome. Thus, fine anesthesia is safe and feasible. Key words: Anesthesia; Pelvic neoplasms

Three-dimensional printing and computer navigation assisted hemipelvectomy for en bloc resection of osteochondroma

Rationale:Three-dimensional (3D) printed templates can be designed to match an individual's anatomy, allowing surgeons to refine preoperative planning. In addition, the use of computer navigation (NAV) is gaining popularity to improve surgical accuracy in the resection of pelvic tumors. However, its use in combination with 3D printing to assist complex pelvic tumor resection has not been reported.Patient concerns:A 36-year-old man presented with left-sided pelvic pain and a fast-growing mass. He also complained of a 3-month history of radiating pain and numbness in the lower left extremity.Diagnoses:A biopsy revealed an osteochondroma with malignant potential. This osteochondroma arises from the ilium and involves the sacrum and lower lumbar vertebrae.Interventions:Here, we describe a novel combined application of 3D printing and intraoperative NAV systems to guide hemipelvectomy for en-bloc resection of the osteochondroma. The 3D printed template is analyzed during surgical planning and guides the initial intraoperative bone work to improve surgical accuracy and efficiency, while a computer NAV system provides real-time imaging during the tumor removal to achieve adequate resection margins and minimize the likelihood of injury to adjacent critical structures.Outcomes:The tumor mass and the invaded spinal structures were removed en bloc.Lessons:The combined application of 3D printing and computer NAV may be useful for tumor targeting and safe osteotomies in pelvic tumor surgery.

Lateral lumbar vertebral body screw predisposes to neuralgia after limb-salvage surgery for pelvic tumors: a single-center, retrospective study of 349 cases.

To investigate the incidence and risk factors of neuralgia after limb-salvage surgery for pelvic tumors with focus on the reconstruction methods. We included 349 cases of pelvic tumors treated with internal hemipelvectomy and reconstruction in our center from January 2009 to May 2015. None of these cases had major lumbosacral nerves invaded by the tumors. Demographic and medical data were reviewed and documented for statistical analyses. The locations of lateral lumbar vertebral body screws (LLVBSs) were evaluated in 26 cases. The overall incidence of post-operative neuralgia was 8.3%. Pre-admission requirement of analgesics (OR 4.089; 95% CI 1.711-9.774) and application of LLVBS (OR 11.848; 95% CI 4.369-32.129) were independent risk factors of neuralgia. The horizontal location of LLVBS did not affect the incidence of neuralgia when it was placed near the midline of the vertebra. The incidence of post-operative neuralgia was 8.3% in this study cohort. The LLVBS technique could increase the risk of post-operative neuralgia.