Abstract Background Cerebral infarction (CI) is an unusual complication in patients with bleeding disorders. To our knowledge, this is the first case of postoperative internal border-zone infarction (I-BZI) from Hemophilia A. Case presentation We present a case of Hemophilia A developing I-BZI, after surgical treatment of giant hemophilic pseudotumor. A 36-year-old man was introduced from other hospital by Hemophilia with giant hemophilic pseudotumor in his left thigh. Patient and his relatives did not have a history of thrombophilia. After excluding the relevant surgical contraindications, we performed the operation of pseudotumor resection. Prior to surgery, blood tests revealed hemoglobin of 137 g/L. FVIII activity was 1.5%. Activated partial thromboplastin time (APTT) was 71.50 s and D-dimer was 3.33 mg/L FEU. Immediately before surgery, the patient received an intravenous infusion of FVIII products (Xyntha®) at a dose of 3500 IU for his body weight of 80 kg. Post-operative day two (POD2), patient developed vomiting, decreased response, and dysarthria. Hemoglobin was 54 g/L with blood pressure of 110/70 mmHg. Magnetic resonance imaging of the brain showed there were multiple acute cerebral infarctions in bilateral lateral ventricles (internal border zone) and multiple ischemic foci in the white matter areas and basal ganglia of the bilateral cerebral hemispheres. This case suggested that acute severe anemia can be one of the causes of I-BZI. Conclusions For the treatment of I-BZI caused by acute anemia from Hemophilia A, volume expansion, red blood cell supplement and continuous improvement of coagulation with suitable dose of factor VIII (FVIII) should be considered to improve prognosis.
Gangrenous cholecystitis is a potentially fatal complication of acute cholecystitis that presents with right upper quadrant pain and sepsis. Due to the overlap in clinical features with ascending cholangitis, gangrenous cholecystitis can be easily misdiagnosed, resulting in treatment delay. While the gold standard of diagnosis of gangrenous cholecystitis is direct visualization during surgery and tissue sampling to pathology, some imaging features can guide the diagnosis to appropriate early surgical treatment of gangrenous cholecystitis. A 78-year-old female presented to the emergency department with right upper quadrant pain, sepsis, and altered mental status. Imaging findings on ultrasound and CT were suggestive of gangrenous cholecystitis. However, clinically the patient presented with ascending cholangitis symptoms. Instead of an emergent cholecystectomy, percutaneous cholecystostomy (PTC) was performed. After the PTC, the patient worsened clinically and despite surgical intervention, the patient expired due to septic shock and multiple organ failure.
A mammary myofibroblastoma is a rare benign lesion found within the breast tissue of both males and females. Although it is a benign mass, it may mimic breast carcinoma on mammography and sonographic imaging. This is a case report of a 68-year-old male with a history of prostate cancer presenting with a tender and palpable mass of the left breast in the 11 o’clock position. Ultrasound-guided core biopsy was performed and pathology confirmed the diagnosis of myofibroblastoma of the breast. Mammary myofibroblastoma should be considered in a patient presenting with a breast mass, particularly older men and postmenopausal women. A core biopsy should be obtained to rule out a more serious diagnosis.
We present a case of a patient who presented to the emergency department with vague abdominal pain one month after undergoing a left atrial ablation procedure for atrial fibrillation. While in the emergency department, the patient started to have episodes of hematemesis. Esophagogastroduodenoscopy (EGD) was performed and the patient become hypotensive and unresponsive after. Imaging confirmed atrioesophageal fistula and widespread cerebral air emboli and diffuse ischemia. Air emboli were likely introduced through the fistula during the EGD.
Background: Anterior cervical trans-pedide screw fixation was introduced to overcome some of the disadvantages associated with anterior cervical corpectomy and fusion. In vitro biomechanical studies on the transpedicle screw fixation have shown excellent pull-out strength and favorable stability. Comprehensive biomechanical performance studies on the trans-pedicle screw fixation, however, are lacking. Methods: The control computed tomography images (C2-T2) were obtained from a 22-year-old male volunteer. A three dimensional computational model of lower cervical spine (C3-T1) was developed using computed tomography scans from a 22 year old human subject. The models of intact C3-T1 (intact group), anterior cervical trans-pedide screw fixation (trans-pedicle group), and anterior cervical corpectomy and fusion (traditional group) were analyzed with using a finite element software. A moment of 1 N.m and a compressive load of 73.6 N were loaded on the upper surface and upper facet joint surfaces of C3. Under six conditions, four parameters such as the range of motion, titanium mesh plant stress, end-plate stress, and bone -screw stress were measured and compared on two treatment groups. Findings: Compared with the intact model, the range of motions for treatment groups were decreased. Compared with cervical corpectomy and fusion, the titanium plant, C4 upper end-plate and C7 lower end-plate stresses in trans-pedicle group were reduced. No significant difference was discovered on bone-screw stress between the two groups for lateral flexion and rotation, but bone-screw stress is smaller in trans-pedicle group when compared with traditional group. With exception of individual difference, trans-pedide group had better biomechanical results than traditional group in range of motions, titanium mesh plant stress, end-plate stress and bone-screw stress. Interpretation: The trans-pedicle method has better biomechanical properties than the anterior cervical corpectomy and fusion making it a viable alternative for cervical fixations.
Background Injection of cement during vertebroplasty and kyphoplasty can leak into surrounding structures and could be symptomatic. Purpose To identify the sites and incidence of cement extravasation after kyphoplasty and vertebroplasty, and to evaluate their impacts on clinical outcomes. Material and Methods A retrospective review of 316 patients treated with kyphoplasty and vertebroplasty; 411 cases were included (223 kyphoplasty and 188 vertebroplasty). Cement extravasation was evaluated postoperatively by computed tomography (CT) scan of the spine. Clinical outcomes were assessed by visual analog scale (VAS) and Oswestry Disability Index (ODI). Results There was a statistically significant difference in the incidence rate of cement extravasation between vertebroplasty and kyphoplasty groups ( P < 0.04). The most common site of cement extravasation was in paravertebral soft tissues for vertebroplasty (n = 33, 40.7%) and for kyphoplasty (n = 30, 30%). In the subgroup where cement leaked into the intradiscal space, adjacent vertebral body fractures occurred in 3/26 vertebrae (11.5%) in the vertebroplasty group and in 2/18 vertebrae (11.1%) in the kyphoplasty group. Both groups showed a statistically significant decrease in both VAS ( P < 0.001) and ODI scores ( P < 0.001). There was no significantly difference in patient satisfaction between those who had cement extravasation and those who did not, in both groups. Conclusion Kyphoplasty has an advantage in terms of less risk of cement extravasation. However, this factor did not reflect on subsequent sequelae or final clinical outcomes. This study did not find a distinct correlation between intradiscal cement extravasation and increased risk of adjacent vertebral fractures.
Purpose The purpose of this study was to examine time to union of extra-articular distal tibia nonunions based on fracture type and fixation methods: intramedullary nail (IMN), plate osteosynthesis (PO), and external fixation (EF).Methods This retrospective chart review included all patients who presented at a Level I trauma center with AO/OTA 43A & distal third 42A-C fracture nonunions between 2008 and 2014. Fixation methods were recorded and patient course was followed until nonunion had healed clinically.Results Thirty-three distal tibia nonunions were included, and 29 reached eventual union (88%). Five AO/OTA fracture types were present. Mean times to union from nonunion diagnosis between original fracture types were compared (p = 0.203). Comminuted fracture types had longer times to union from nonunion diagnosis compared to simple fracture types (78 vs. 46 weeks, p = 0.051) and more revision fixations (1.5 vs. 0.5, p = 0.037). Mean time to union from nonunion diagnosis was shorter when no revision fixation was done compared to revisions (15 vs. 42 weeks, p = 0.102). Times to union from nonunion diagnosis without revision fixation were: IMN (12 weeks), PO (27 weeks), and EF (13 weeks) (p = 0.202). Times to union from definitive revision fixation were: IMN (17 weeks), PO (21 weeks), and EF (66 weeks) (p = 0.009), with EF taking significantly longer than both other methods. 21 patients (64%) underwent revision fixation. Revision fail rates were: IMN (0/6, 0%), PO (2/8, 25%), and EF (15/21, 71%). Time to union was longer in revisions that changed fixation method compared to revisions that used the same method (51 vs. 18 weeks, p = 0.030). Deep infections were also associated with longer union times (81 vs. 47 weeks, p = 0.040).Conclusions In this nonunion population, comminuted fracture types needed more time and revisions to reach union. Time to union was only clinically shorter when revision fixation was not performed, but IMN and PO were both successful fixation options with significantly shorter times to union than EF. Mean time to union increased even more when revision of fixation method was performed vs. exchange revision, as did nonunions with deep infections.
ObjectiveTo report and evaluate the outcomes of patients undergoing definitive treatment for distal femur nonunion after initial treatment with a locking plate.MethodsFourteen patients who had undergone definitive treatment at an academic Level 1 trauma center from May 2007 to December 2013 for distal femur nonunion were identified from a fracture database. Thirteen of them were female; the average age was 65 years (range, 50–84 years). Ten patients had sustained their injuries in falls at ground level, and four in motor vehicle accidents. Twelve patients were obese (body mass index ≥30), 10 had diabetes, none were current smokers, and one had an open fracture classified as type IIIa according to the Gustilo–Anderson classification system for open fractures. The fractures were classified according to the AO classification system for distal femur fractures; there were three type 33‐A1, six 33‐A2, two 33‐A3 and three 33‐C3 fractures. Methods of definitive treatment involved open reduction and internal fixation (ORIF) revision, medial plating, bone grafting and the use of other biologic materials.ResultsEight of the 14 patients (57%) achieved union during follow‐up. Definitive treatment for nonunion involved ORIF revision in 11 cases. Three patients who did not undergo ORIF revision were treated with iliac crest stem cell autografts, bone graft substitutes or recombinant human‐bone morphogenetic protein‐2 (rh‐BMP‐2). Other treatments included rh‐BMP‐2 (12 cases), iliac crest bone autograft (five), iliac crest stem cell autograft (two), crushed cancellous bone allograft (three), CaSO 4 and tricalcium phosphate bone graft substitute (two) and demineralized bone matrix (one). The average time from definitive treatment to union was 19 weeks (range, 12–51 weeks). Two of the 11 cases who underwent ORIF revision had medial plates added to improve biomechanical stability and prevent varus collapse. This was also performed in one patient with a grade III open type 33‐C3 fracture and one with a closed 33‐A2 fracture. Five study patients had comminuted fractures. Two had type 33‐A3 and three type 33‐C3 fractures. Both patients with 33‐A3 fractures and 2 two with 33‐C3 fractures had persistent nonunion at the end of follow‐up.ConclusionsDefinitive treatment of distal femur nonunion after initial treatment with a locking plate had a low rate of success in this study, suggesting that this procedure is ineffective as a definitive treatment for distal femur nonunion.
Spinal gout most commonly present as back or neck pain with majority of reported patients with elevated uric acid. The diagnosis of spinal gout is confirmed with the presence of negatively birefringent monosodium urate crystals in tissue. Treatment for spinal gout involves medication for the reduction of uric acid level and surgery if patient symptoms failed to respond to medical treatment.
This review summarizes the treatment and resulting outcomes for total talar dislocation. The PubMed database was searched for articles about humans with total talar dislocation published in the English language in the last twenty years. The following data were entered into a Microsoft Excel spreadsheet: type of dislocation, nature of associated fractures (if any), type of reduction/fixation utilized, immobilization, weight-bearing status, outcome, complications and average follow-up time. Thirty-nine articles reporting a total of 86 cases of total talar dislocation are included in this review. Seventy-three of these were open injuries and 13 closed. Forty-three cases had an associated foot or ankle fracture, 32 of those cases specifically having a fracture of the talus. The talus was preserved in the initial management of 74 cases, whereas the remaining 12 cases were managed by primary talectomy. The mean duration of follow-up was 32 months. Twenty-two cases required a secondary arthrodesis or another additional procedure. A good outcome was achieved in 35% of cases, a fair outcome in 37% and a poor outcome in 27%. The complication of avascular necrosis (AVN) occurred in 22 cases and 14 subjects developed clinically significant osteoarthritis. Generally, the outcome of current treatments associated with total talar dislocation is not ideal, only 1/3 of cases achieving good outcomes. So far, preservation of the talus is the best treatment option. AVN is still a relatively common complication even in the absence of fracture or postoperative infection.
Chordoma is a rare but invasive low-grade malignant tumor. Molecular targeted therapy (MTT)---especially against the angiogenesis of the tumor---may be a potentially effective option for its treatment. A number of studies have shown that survivin and vascular endothelial growth factor (VEGF) may play a significant role in tumor angiogenesis, but their significance in sacral chordoma has not been thoroughly investigated.
This study was designed to itemize and analyze the classification of fracture types and their corresponding outcomes in an attempt to provide a better understanding of the current treatment methods. Two PubMed searches were performed using the words “periprosthetic distal femur fracture” and “periprosthetic supracondylar femur fracture” in studies that were published in the previous 10 years (2004–2014). Data from 41 articlesthat met the general inclusion criteria, were collected and categorized into fracture type and treatment method groupings. Healing outcome and complications were the two parameters used to analyze the data. Treatment techniques were grouped in the following categories: locking plate, non‐locking plate, intramedullary nail/rod, screw, blade plate, cerclage wires, allograft, external fixation, revision arthroplasty, non‐operative, and other. Classification systems by Lewis and Rorabeck, the Association for Osteosynthesis/Orthopedic Trauma Association (AO/OTA), Su et al., Neer et al., Kim et al., Backstein et al., and the Société Française de Chirurgie Orthopédique et Traumatologique were reported. In total 448 fractures were identified, of which Rorabeck type II was the most common fracture studied. The two most successful treatment options for periprosthetic distal femur fractures were locking plate (87%) and intramedullary nail/rod (84%). The most frequent complications associated with periprosthetic distal femur fractures included non/mal/delayed union and the need for revision. Locking plates used to treat Rorabeck type II fractures had a complication rate of 35% and those treated with intramedullary nailing had a higher complication rate of 53%. In conclusion, the most frequent type of periprosthetic distal femur fracture after total knee arthroplasty was Rorabeck type II. The most common treatments for these types of fractures are locked plating and intramedullary nailing, with similar healing rates of 87% and 84%, respectively. However, the complication rate for locked plating was lower than for intramedullary nailing.
Pseudomeningoceles are rare but well-documented complications of spinal surgery. They are extradural collections of cerebrospinal fluid that usually result from incidental tears in the dura. Multiple cases of posterior bony erosion because of postsurgical pseudomeningoceles have been described previously. However, this is the first reported case of vertebral body erosion because of an anterior iatrogenic pseudomeningocele [1–3].
BACKGROUND CONTEXT: Previous studies have demonstrated the use of bone marrow mesenchymal stem cells (BMSCs) in tissue-engineering treatments to slow or reverse diseased intervertebral discs. Several approaches have successfully used the coculturing of stem cells with disc-native nucleus pulposus cells (NPCs) with the evidence of transformed BMSCs into NP-like cells, increased activity and matrix production by NPCs, or elements of both. The influence of the cytokine transforming growth factor-beta (TGF-beta) in the differentiation of BMSCs into NP-like cells and its upregulation in coculture to increase matrix production are well established. However, the role of the inflammatory signaling molecule nuclear factor kappa B (NF-kappa B) in intervertebral disc degeneration is far less clear, although there is some existing evidence suggesting its role in the pathogenesis and progression of disc disease. A limited number of studies in other pathologies have alluded to the antagonistic relationship between both proteins. To date, there is no such investigation of their dynamic role in coculture of BMSCs and NPCs.PURPOSE: The purpose of this study was to investigate the relationship of the regenerative effects of BMSCs cocultured with NPCs. The authors hypothesized that as levels of TGF-beta increase in the coculture, the levels of NF-kappa B will concomitantly decrease. This would in turn be reflected by an increase in the expression of messenger RNA markers of the nucleus pulposus matrix that includes aggrecan, Type II collagen (CII), and SOX-9 and an increase in the cellular proliferation.STUDY DESIGN/SETTING: This study is based on a coculture with the contact of rabbit NPCs and BMSCs.METHODS: Bone marrow mesenchymal stem cells were cocultured with NPCs at a ratio of 1: 1 and compared with BMSC and NPC controls cultured alone. Cell proliferation was evaluated by Cell Counting Kit-8 from 3 to 9 days. Gene expressions of aggrecan, CII, and SOX-9 was assayed by reverse transcription-polymerase chain reaction from 5 to 14 days. Detection of TGF-beta 1 and NF kappa B was determined by enzyme-linked immunosorbent assay, and immunohistochemical staining was carried out to evaluate CII synthesis.RESULTS: After 3 days, cellular proliferation of the cocultured group exceeded that of controls. After 11 days, the expression of SOX-9 in the cocultured group had also exceeded controls. Furthermore, after 14 days, expressions of aggrecan and CII significantly exceeded controls. Immunohistochemical stains of CII in the NPC control group were positive at each point in time and demonstrated strongest expression at 14 days. Coculturing BMSCs with NPCs, therefore, seems to have resulted in the promotion of aggrecan, CII, and SOX-9 gene expressions. Finally, after 11 days, TGF-beta 1 content of the cocultured group significantly exceeded control levels, whereas NF-kB content had significantly lowered.CONCLUSIONS: Coculture of BMSCs may be able to delay NPC matrix degeneration potentially through the concomitant upregulation of TGF-beta and the downregulation of NF-kappa B pathway. (C) 2015 Elsevier Inc. All rights reserved.
UNLABELLEDDespite recent developments reported in studies of (-)-epigallocatechin-3-gallate (EGCG), its early preventive effect of mitigating bone loss is not well understood. We investigated the effect of EGCG in preventing bone loss in ovariectomized (OVX) female rats, and explored the possible underlying mechanisms. Twelve-week-old female Sprague-Dawley rats, were divided into 3 groups: group A received intraperitoneal EGCG for 12 consecutive weeks, begun 3 days after ovariectomy; group B received ovariectomy alone; group C, received a sham operation. At the end of the experiment, tibias and femurs were harvested for: (1) micro-CT scanning and measurement of bone mineral density (BMD) and bone morphological parameters; (2) a 3-point bending test; (3) HE staining and an immunohistological study investigating Sema4D expression.RESULTSThe BMD and BV/TV of group A were significantly higher than for the OVX group. The trabecular separation (Tb.Sp) of group A was significantly lower than for group B. RESULTS from the 3-point bending test showed no statistical significance among all the groups. Bone histological studies indicated that trabecular bone was denser in group C, while group B had less dense trabecular bone, and the bone morphological status of group A was intermediate between groups A and C. The immunohistological study demonstrated that Sema4D was more highly expressed as a percentage of the brown-stained area in group B than in the other 2 groups.CONCLUSIONEGCG had a positive effect on mitigating bone loss in ovariectomized rats, and it inhibited Sema4D expression in bone tissue. Early stage supplementation of EGCG at a dose of 10 mg/kg/day after the onset of ovariectomy did not entirely eliminate bone loss.
Objective The number of patients requiring knee and hip arthroplasty has been steadily increasing, and periprosthetic fractures are on the rise. Locking plates are the most common treatment for periprosthetic fractures, but the use of cerclage wires with locking plate fixation has been controversial. Methods Forty‐seven patients with periprosthetic femur fractures were reviewed retrospectively. Twenty‐four patients received locking plate alone and twenty‐three patients were treated with locking plate and cerclage wires. Patients were evaluated for clinical and radiographic signs of union at two, six, twelve, twenty‐four, and forty‐eight weeks postoperatively. Results The average follow‐up time in the plate group was 9.4 ± 6.7 months, while it was 6.0 ± 4.2 months in the cerclage wire group. The time to union in the cerclage wire group (3.6 ± 1.0 months) was significantly less than the plate group (4.8 ± 2.6 months). The group with the cerclage wires had a significantly lower revision rate of 0% compared to 20.8%. There was no statistical significance of union rate and complication rate between the two groups. Conclusion Cerclage wires used with locking plate fixation successfully treats periprosthetic fractures of the femur with faster time to union, less complication, and fewer revisions.
BACKGROUND CONTEXT: Low back pain is a frequently occurring disease caused by intervertebral disc degeneration. Mesenchymal stem cells (MSCs) are a possible treatment modality. Studies have shown MSCs can be transformed into nucleus pulposus-like cells under normoxic conditions. However, this is not a true representation of the hypoxic environment nucleus pulposus cells experience during in vivo growth and differentiation.PURPOSE: To determine the effects of a hypoxic environment on the differentiation of human placenta-derived mesenchymal stem cells (PMSCs) to nucleus pulposus-like cells.STUDY DESIGN: An experimental study.METHODS: Placenta-derived mesenchymal stem cells were cultured and the mesenchymal lineage was confirmed by flow cytometry. Two groups of PMSCs were then cultured under different oxygen concentrations creating a hypoxic group and normoxic group. The proliferation of cells in each group was compared by cell counting kit-8 on Day 1, 3, 5, and 7. Real-time polymerase chain reaction on Days 3 and 7 compared the expressions of Sox-9, Type II collagen, aggrecan, and hypoxia inducible factor-1 alpha (HIF-1 alpha) between the two groups. Immunofluorescence was used to compare the expression of Type II collagen between the two groups after 14 days.RESULTS: Placenta-derived mesenchymal stem cells were successfully isolated and cultured. Mesenchymal markers were positive. On Days 3 and 5, the hypoxic group had a significantly higher proliferation rate than the normoxic group (p<.05). The expression of Sox-9 and HIF-1 alpha was significantly higher (p<.05) in the hypoxic group at Days 3 and 7. Type II collagen and aggrecan expressions were significantly higher (p<.05) in the hypoxic group at Day 7. The hypoxic group stained more positive for Type II collagen at Day 14.CONCLUSIONS: Hypoxic conditions lead to an increased differentiation and proliferation of nucleus pulposus-like cells. Placenta-derived mesenchymal stem cells cultured in nucleus pulposus inducing media and a hypoxic environment show enhanced expression of the nucleus pulposus-like cell markers, Sox-9, Type II collagen, aggrecan, and HIF-1 alpha. (C) 2014 Elsevier Inc. All rights reserved.
Indirect reduction and posterior pedicle screw fixation have been reported with variable outcomes. However, there is no study that reports on disc space height change following short segment pedicle screw instrumentation without fusion.
C2 laminar screws have become an increasingly used alternative method to C2 pedicle screw fixation. However, the outcome of this technique has not been thoroughly investigated. A total of 35 cases with upper cervical spinal instability undergoing C2 laminar screw fixation were reviewed. All cases had symptoms of atlantoaxial instability, such as craniocervical junction pain, and were fixed with the Vertex cervical internal fixation system. A total of 68 screws were placed and hybrid constructs (a C2 translaminar screw combined with a C2 pars screw) were incorporated in two patients. In this series, there were no intraoperative complications and no cases of neurological worsening or vascular injury from hardware placement. Computed tomographic scans demonstrated a partial dorsal laminar breach in ten patients. None of these resulted in neurological symptoms. None of the patients was found to have a breach of the ventral laminar cortex. All the C2 laminar screws fixations were performed successfully. There was no instability seen on the films with no evidence of hardware failure or screw loosening during the follow-up period in all patients. In conclusion, C2 laminar screw technique is straightforward and easily adopted; it can efficiently and reliably restore upper cervical stability. It is an alternative method to C2 pedicle screw fixation, especially in patients with unilateral occlusion of vertebral artery and pedicle deformity of C2.
Study Design: A retrospective study, analyzing midterm results of transcatheter arterial embolization (TAE) for removal of a sacral chordoma.Objective: To develop a suitable method to maximally remove the tumor.Summary of Background Data: Although previous reports have reported the use of TAE for removal of tumors, there is currently no data available on using this method to treat sacral chordomas.Methods: Thirty patients with sacral chordomas, who underwent surgical treatment from January 1994 to September 2005, were selected. All 30 patients underwent the posterior approach after TAE of the main arteries that supplied the sacral chordoma. The average follow-up was 44.6 months after the operation. The blood lost during the operation, blood transfusion, and the blood drained from the patient after the operation was reviewed. In addition, the sphincter muscle function of the bladder and bowel was observed.Results: The intraoperative blood loss averaged 1200 mL during the removal of the tumor. The average blood drained from the patient after the operation was 650 mL. The average blood transfusion postoperatively was 1080 mL. Of the 30 patients, 12 had recurrence and 2 died of tumor metastasis. In the 17 patients whose sacral nerve roots had been bilaterally reserved at and above the S3 level, the sphincter muscle function of the bladder and bowel was good, whereas the function of the sphincter muscles was impaired in 2 patients with nerve roots reserved only at and above the S1 level. In 1 case, colostomy and ureterocutaneosomy were used.Conclusions: In comparison with historical literature, preoperative TAE for excising the sacral tumor can significantly decrease intraoperative blood loss, make the surgical field clear, possibly eliminate the need for using an anterior approach, and facilitate the maximal removal of the sacral chordoma. It is an encouraging technique for excising the sacral chordomas.