CT Three-dimensional Reconstruction Research Articles

Image study of anteromedial cortical morphology of intertrochanteric fractures

To study the anteromedial cortical morphology of intertrochanteric fracture with CT three-dimensional reconstruction technique, and to provide a reference for further study of cortical buttress reduction theory. CT data of 75 patients with unstable intertrochanteric fracture with complete imaging data treated between January 2016 and January 2019 were retrospectively analyzed, including 32 males and 43 females, aged 65-98 years (mean, 79.8 years). According to AO/Orthopaedic Trauma Association typing of 2018 edition, there were 46 cases of 31-A2.2 type and 29 cases of 31-A2.3 type. The image processing techniques such as segmentation modeling and virtual reset were performed. The thickness of the cortex at the anteromedial corner, the angle between the anterior wall fracture line and the coronal horizontal line, the angle between the medial wall fracture line and the sagittal horizontal line, the width of the cortex supported by the medial wall were measured, and the morphology of the cortical bone at the anteromedial corner were observed. The angle between the anterior wall fracture line and the coronal horizontal line was 51.8-72.6°, with an average of 62.4°; the angle between the medial wall fracture line and the sagittal horizontal line ranged from 17.6° to -47.3°, with an average of -15.8°; the thickness of the cortex at the anteromedial angle was 3.6-6.1 mm, with an average of 4.4 mm; and the width of the cortex supported by the medial wall was 14.3-21.2 mm, with an average of 16.8 mm. The morphology of the cortical bone at the anteromedial corner had 3 forms: angle with femoral neck axis >90°, 57 cases (76.0%); perpendicular to femoral neck axis, 7 cases (9.3%); angle with femoral neck axis <90° (including reverse angle), 11 cases (14.7%). CT three-dimensional reconstruction can clearly show the cortical morphology and the direction of the fracture line of intertrochanteric fracture, which can indicate the stability of the intertrochanteric fracture after reduction, and has a good guiding on the form of cortical buttress reduction.

Preliminary application of endoscopic titanium clip localization combined with three-dimensional CT reconstruction in the determination of resection margin of gastric central cancer under laparoscopy

Objective: To evaluate the accuracy of endoscopic titanium clip localization combined with CT three-dimensional reconstruction for the control of incision margin in early gastric cancer under laparoscopy. Methods: A prospective analysis was made for gastric cancer whose lesions were located in the middle of the stomach and T stage was 1 to 2 from October 2017 to January 2019 at Department of Gastrointestinal and Pancreatic Surgery, Zhejiang Provincial People's Hospital. Totally 25 patients were eventually enrolled in the study. There were 17 males and 8 females aging of (63.6± 7.2) years (range: 48 to 77 years). All cases were treated with titanium clip localization under endoscope combined with CT three-dimensional (3D) reconstruction to construct a virtual panorama of gastric cavity and lesions, and to design surgical margins. Laparoscopic surgical resection was performed according to the surgical margins designed before operation. The distance from the gastric angle to the origin of the minor curvature of the incisional margin, the distance from the gastric angle to the the center of lesion and the distance of the upper incision margin were measured under three-dimensional CT reconstruction and under actual specimen. Paired t test was used to compare the three distances measured by two methods. Results: The measured distances from the gastric angle to the center of the lesion and the proximal incisional margin under 3D reconstruction CT were according to the measured values of actual specimens ((2.67±1.38) cm vs. (2.83±1.56) cm, t=1.51, P=0.14; (5.23±0.60) cm vs. 5 cm, t=1.93, P=0.07); the measured distances from the gastric angle to the origin of the minor curvature of the incisional margin under CT 3D reconstruction were different with the measured values of solid specimens ((5.94±0.94) cm vs. (6.37±0.90) cm, t=3.52, P=0.00). Conclusion: The method of titanium clip localization combined with CT 3D reconstruction can provide a feasible laparoscopic localization method and incision edge solution for T1 to 2 gastric central cancer.

Classification of Hypertrophic Gastrocnemius Muscle and Its Treatment with Botulinum Toxin A

Treatments including selective neurectomy, muscle resections and botulinum toxin A (BTX) injections have been used to improve the stocky appearance of calves. BTX injection has the advantages of high efficiency and is almost noninvasive. However, criterion standards of injection are still missing. We aimed to establish a method to classify the hypertrophic calf for a personalized treatment and set up an injection protocol based on the findings. Three-dimensional CT reconstruction was used to measure the thickness and cross-sectional area of the triceps surae. B-mode ultrasound and palpation were used to evaluate the muscle thickness and determine the dosage. Patients were followed 3 and 6months after the treatment. A total of 112 legs were classified into three degrees of thickness (< 15mm, 15-25mm and > 25mm). Twenty-seven subjects were treated with an individualized BTX (100-300U). Maximal circumference decreased 0.33 ± 0.00cm after 3month (p < 0.05) and 0.67 ± 0.11cm after 6months (p < 0.01). The angulated calf contour was improved. No severe side effects were reported. Localizing and dosage are the key points when applying BTX. Dosage should be decided by muscle thickness instead of circumference. BTX treatment improves the prominent contour of the calf rather than reducing the volume. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

Anterior Atlantooccipital Transarticular Screw Fixation: A Cadaveric Study and Description of a Novel Technique.

Retrospective analysis of collected data and operative experiment on human cadavers. To describe a novel technique of the anterior atlantooccipital (AC) transarticular screw fixation, and to analyze the pertinent anatomy with cadaveric and radiographic assessment of the feasibility, safety, and general applicability of this technique. In some situations, the posterior AC fixation techniques may not be possible, or may require supplemental fixation, which include the congenital hypoplasia, absence of the bony elements, and even revision surgery. However, an anterior screw fixation technique may add stability to further attempts at obtaining an arthrodesis. A detailed description of the surgical technique was presented. Three-dimensional (3D) CT reconstruction of the cranioverteral region of 30 patients were performed to determine screw entry points, target points, and proposed screw trajectories. Following screw insertion in eight fresh frozen human cadaver spine specimens, dissection verified screw location relative to structures at risk. The ideal entry point is located caudal to the C1 superior facet joint in line with the medial third of the C1 superior facet. The ideal screw is directed 41.7° posteriorly in the sagittal plane and 11.6° laterally in the coronal plane with a length around 30.4 mm. The feasibility of anterior AC screw fixation was 92% (35/38 cases). There is a risk of injury to the vertebral artery and the hypoglossal nerve. Anterior AC transarticular screw fixation is feasible and can be considered as a salvage technique or an alternative for the posterior AC fixation, as well as the supplement to the anterior occipitocervical fixation. 3.

Quantitative analysis of microscopic structure and gas seepage characteristics of low-rank coal based on CT three-dimensional reconstruction of CT images and fractal theory

The pores/fractures are places for gas migration and storage in coal. Their structure complexity will directly influence the pore structure parameters and gas seepage properties of coal. Therefore, we selected 6 low-rank coal samples and quantitatively studied these influences utilizing the high-resolution micro computed tomography (μCT) and fractal theory. The total pore structure and connected pore structure parameters of 6 samples were acquired from three-dimensional (3D) reconstruction of CT images. The fractal dimensions of total pore structures (Df), solid structures (Ds) and connected pore structures (Dc) were calculated using 3D box-counting method. The relationship between Df and porosity was analyzed through the 3D total pore model, and the relationships between Dc and connectivity as well as permeability were analyzed through the 3D connected pore model. The results show that Df, which is between 2.10 and 2.43, could accurately describe the fractal characteristics of coal and the solid structure of coal is not fractal. The porosities of the 6 samples are between 3.33% and 12.18% and their relationship with Df can be defined by a monotonically increasing power function. The larger the Df is, the larger the porosity of the tested coal sample. Dc is between 2.28 and 2.32, the connectivity is between 0.54 and 0.83, and the permeability is in the range of 1.76–11.63 × 10−8 m2 (except samples 1 and 6). Dc is negatively correlated with connectivity and permeability and its relationship with connectivity and permeability can be represented by the quadratic function and monotone decreasing power function, respectively.

In vivo measurement of three-dimensional motion of the upper cervical spine using CT three-dimensional reconstruction

Using the CT three-dimensional reconstruction to measure the activity degree of atlanto-occipital joint and the atlantoaxial joint in different directions and its coupling movement in healthy volunteers, and three dimensional motion range of the maximum rotation position of the upper cervical spine of cervical spondylosis patients, and to analyze the differences, verifing the reliability of the method at the meantime. From January 2014 to June 2015, 20 healthy adult subjects(healthy adult group), and 26 patients with cervieal spondylosis(cervical spondylosis group) were selected. In healthy adult group, there were 11 males and 9 females, aged from 22 to 26 years old with an average of (24.0±1.2) years, and in cervical spondylosis group, there were 24 males and 2 females, aged from 36 to 72 years old with an average of (52.8±8.6) years. Healthy adults underwent CT examination in neutral position, maximum right rotation, maximum right lateral bending, maximum flexion and extention, and cervical spondylosis patients underwent CT examination in neutral position, maximum right rotation. Then the software Mimics was used to reconstruct occiput (Oc), atlas(C1) and axial(C2) vertebral three-dimensional image. Three virtual non-collinear markers were positioned on prominent structures of foramen magnum, C1 and C2. The 3D spatial coordinates of these virtual anatomical markers entail the definition of an anatomical local coordinate system which represent the position and orientation of the bones. Segmental motions were calculated using Eulerian angle in three major planes, and the difference between cervical spondylosis group and healthy adult group were compared. Due to the inaccuracy in anatomical landmark idenrification, two groups were measured 3 times, and the reliability of the experimental metnod was verified by the intra-group correlation (intra-group ICC) and the inter-group correlation coefficient(inter-group ICC). Reliability verification results:the intra-group ICC and inter-group ICC results were all above 0.90, and the measurement method had high reliability. Three-dimensional activity of the upper cervical spine in healthy adults:the atlanto-occipital joint had(-6.8±1.5)° coupled left lateral bending and (8.9±2.0)° coupled extension in the maximum right rotation position, and the motion of atlanto-occipital joint had low activity[maximum was(5.3±2.6)°] in the remaining 3 positions; the rotation of atlanto-axial joint was(37.9±5.1)°, accounting for 52.34% of the total cervical spine activity[(72.4±5.0)°] in the maximum right rotation position, and rotational motion was still prominent in the remaining three positions. The relative translations of the upper cervical spine in all direction were small. The average axial rotation angle [(62.0±3.4)] ° of the total cervical spine in cervical spondylosis group was significantly lower than that in the healthy adult group, but the mean axial rotation angles of the atlanto-occipital and the atlantoaxial joint were not significantly different from those of the healthy adults(P>0.05). The three-dimensional CT reconstruction method has high reliability, which can be applied to measure the movement of spine. The upper cervical spine contributed the most to the direction of rotation, and the movement in all directions are accompanied by coupled motion in the other direction. There was no significant difference in the rotation of the upper cervical spine between cervical spondylosis patients and normal subjects.

Measurement of the Orbital Soft Tissue Volume in Chinese Adults Based on Three-Dimensional CT Reconstruction.

Quantitative measurement of the orbital soft tissue volume plays a very important role in the study of orbital diseases. The purpose of this study is to establish a computed tomography- (CT-) based three-dimensional (3D) reconstruction model and measure the orbital soft tissue volume in Chinese adults. We collected data from 103 Chinese adults (52 males and 51 females) who underwent orbital CT. The CT images of these adults were used to reconstruct a 3D model of the orbital bony cavity, orbital fat, extraocular muscle, and intraorbital optic nerve using Mimics software, and their respective volumes were measured. The mean (±SD) orbital bony cavity volume (OV), orbital fat volume (FV), extraocular muscle volume (MV), and intraorbital optic nerve volume (iONV) of the males were 22.2 ± 2.2 cm3, 8.9 ± 1.8 cm3, 1.9 ± 0.34 cm3, and 0.41 ± 0.08 cm3, respectively. The mean OV, FV, MV, and iONV of the females were 20.2 ± 1.5 cm3, 8.1 ± 1.7 cm3, 1.6 ± 0.3 cm3, and 0.36 ± 0.074 cm3, respectively, which were all significantly lower than those in males (all p < 0.05). FV (r = 0.370; p < 0.001) and MV (r = 0.283; p=0.007) were significantly correlated with body mass index (BMI), while iONV was not correlated with BMI (r = −0.070; p=0.480). This study shows that FV, MV, and iONV were higher in males than in females. With increasing BMI, FV and MV both increased, but iONV did not exhibit this trend.

Current concepts of diagnostic techniques and measurement methods for bone defect in patient with anterior shoulder instability

To summarize the diagnosis and measurement methods of bone defect in anterior shoulder instability (glenoid bone defect and Hill-Sachs lesion). The related literature on the diagnosis and measurement of the bone defect in anterior shoulder instability was reviewed and summarized. The commonly used techniques for the diagnosis of anterior glenoid bone defect and Hill-Sachs lesion of humeral head include X-ray, CT, MRI, arthroscopy, arthrography. The methods for measuring the degree of anterior glenoid bone defect include Griffith method, glenoid index method, Pico method, and best-fit circle method. The indexes for measuring the Hill-Sachs lesion include the length, width, depth, and volume. X-ray is mainly used for primary screening. Best-fit circle method on three-dimensional (3D) CT reconstruction is commonly used to measure the glenoid bone defect currently. Glenoid track theory on 3D CT reconstruction is popular in recent years. Reliability of measuring the glenoid bone defect and Hill-Sachs lesion with MRI and arthroscopy is still debatable. Arthrography is more and more used in the diagnosis of shoulder joint instability of bone defect and concomitant soft tissue injury. How to improve the accuracy of evaluating glenoid bone defect and Hill-Sachs lesion before surgery still need further study.

Nursing care of lower cervical spine fracture treated with 3D print microporous titanium artificial vertebral body

Objective To summarize the perioperative nursing measures and effects of 3D printed artificial cervical vertebrae for lower cervical spine fractures. Methods Treatment of 15 cases of lower cervical spine fracture with 3D printed artificial cervical vertebrae. Preoperative cervical spine fixation to prevent spinal cord injury, strict observation of clinical symptoms, assist the doctor to perform CT three-dimensional reconstruction of the cervical spine, and calculate the physiological height of the injured vertebrae; maintain the surgical position fixed during surgery, carefully prepare the supporting equipment, familiar with the surgical related steps, accurate delivery of all types of surgical instruments to assist with intraoperative fluoroscopy. Postoperative focus on the neck to see if there is swelling, effectively maintain the airway patency, observe changes in spinal nerve function, develop a personalized functional exercise program to promote rehabilitation, and actively prevent complications. Results The JOA score increased from (9.23±1.62) points before surgery to (14.09±1.35) points after surgery, and the improvement rate was 62.55%. There were no complications such as difficulty swallowing, hoarseness, and difficulty breathing. Conclusions Through targeted perioperative care, surgical complications can be reduced and the quality of life of patients improved. Key words: Sub axial; Fracture and dislocation; 3D print microporous titanium artificial vertebral body

Fragment volume and surgical methods in radial head fracture

Objective To investigate the relationship between volume of fracture fragment and surgical methods in patients with radial head fracture. Methods A retrospective study was conducted of the 60 patients with radial head fracture of Mason type Ⅲ who had been admitted to the Department of Hand Surgery, Wuhan Pu＇ai Hospital from January 2013 to December 2016. They were 28 males and 32 females, aged from 26 to 71 years (average, 54.5 years). Of them, 41 underwent open reduction and internal fixation (incision group) and 19 radial head replacement (replacement group). The volumes of radial head and fracture fragment were measured by CT scan and three-dimensional reconstruction of the elbow joint before operation. A volume-weighted ratio R corresponding to a specific radial head fragment was calculated. Correlation between the volume-weighted ratio R of the radial head fragment and the Broberg-Morrey elbow function score was calculated. At the last follow-up, the Broberg-Morrey elbow function score was used to assess the efficacy and complications were recorded in the 2 groups. Results All the 60 patients were followed up for 20 to 36 months (mean, 28.6 months). At the last follow-up, the Broberg-Morrey elbow function score was 86.5±1.3 points (from 72 to 91 points) for the incision group and 93.6±1.4 points (from 78 to 95 points) for the replacement group; the complication rate was 17.1% (7/41) for the former and 15.8% (3/19) for the latter. There was a linear relationship between the volume-weighted ratio R of the radial head fragment and the Broberg-Morrey elbow function score in the incision group. The linear regression equation between the two was: y=65.63+0.67x (R2=0.85, P=0.0006). There was no linear relationship between the volume-weighted ratio R of the radial head fragment and the Broberg-Morrey elbow function score in the replacement group (P=0.053). When the Broberg-Morrey elbow joint function score (93.6 points) for the replacement group was substituted into the linear regression equation y=65.63+0.67x (y=93.6), x=41.7. Conclusions In the patients with radial head fracture of Mason type Ⅲ, open reduction and internal fixation may lead to a better prognosis for those with a volume ratio ≥41.7 between the radial head and fracture fragment while radial head replacement may lead to a better prognosis for those with a volume ratio < 41.7 between the radial head and fracture fragment and for those elderly ones with osteoporosis. Key words: Elbow joint; Arthroplasty, replacement; Bone plates; Relationship; Radial head fracture

Ressarch of prior-localization femoral tunnel in medial patellofemoral ligament reconstruction

To introduce the method of prior-localization femoral tunnel by using a special positioning tool under the C-arm radiographic machine before surgery, and to study the effect on the knee function recovery after medial patellofemoral ligament (MPFL) reconstruction. Between January 2014 and January 2016, 32 patients with recurrent unilateral knee patellar dislocation were treated by arthroscopic patellofemoral lateral retinaculum release and MPFL reconstruction. The femoral tunnel position during MPFL reconstruction was prior-localizated under C-arm radiographic machine before operation. There were 8 males and 24 females, aged from 15 to 37 years, with an average of 23.8 years. The time from injury to admission ranged from 1 to 24 months, with an average of 9.7 months. Isometric point distance was measured on CT three-dimensional reconstruction image after operation to evaluate whether the position of femoral tunnel was isometric, and knee joint function was evaluated by Lysholm score. Spearman correlation analysis was performed between isometric point distance and Lysholm score. All the 32 patients were followed up 12-18 months (mean, 14.2 months). No symptoms of patellar subluxation or dislocation was found during follow-up. Patellar extrapolation test and patellar extrapolation fear test were negative. The isometric point distance was 1.5-5.9 mm (mean, 3.44 mm) at 3 days after operation. All femoral tunnels were located in equidistant tunnels. At last follow-up, the Lysholm score of the patients was 92.8±2.1, which was significantly improved when compared with preoperative score (54.4±2.8) ( t=61.911, P=0.000). Isometric point distance was negatively correlated with Lysholm score ( r=-0.454, P=0.009). C-arm radiographic machine can locate the femoral tunnel position of MPFL easily and accurately before operation. The short-term and medium-term effectiveness are satisfactory, and the ionizing radiation injury caused by multiple fluoroscopy during operation is avoided.

Three-dimensional reconstruction of cervical CT vs ultrasound for estimating residual thyroid volume

To compare the accuracy of three-dimensional reconstruction of cervical CT and ultrasound for estimating residual thyroid volume. We performed a retrospective analysis of 17 patients with 21 residual thyroid glands undergoing thyroidectomy surgery between February, 2017 and March, 2018 in our department. We compared the residual thyroid volume in preoperative ultrasound with the intraoperative measurement and the volume measured using threedimensional CT reconstruction before surgery. The maximum vertical and anterioposterior diameters of the residual thyroid measured by preoperative ultrasound differed significantly from the volume data measured intraoperatively (P &lt; 0.05), but the difference in the maximum left-right diameters was not statistically significant (P&gt;0.05). The maximum vertical, leftright, and anteroposterior diameters estimated by three-dimensional reconstruction of cervical CT was all similar with those measured intraoperatively (P&gt;0.05). Compared with ultrasound examination, three-dimensional reconstruction of neck CT is more accurate for estimating the residual thyroid volume and provides more reliable evidence for clinical calculation of postoperative I131 dose for thyroid cancer.

Hammering reverse guide wire technique for safe placement of anterior column retrograde in-tramedullary screw in pelvic and acetabular surgery

Objective To evaluate the efficacy and accuracy of hammering reverse guide wire technique for safe placement of anterior column retrograde intramedullary screw in pelvic and acetabular surgery. Methods From September 2015 to March 2018, 46 patients with pelvic or/and acetabular fracture involving the anterior column were treated with hammering reverse guide wire technique for safe placement of anterior column retrograde intramedullary screw at Department of Orthopaedics, Lishui Municipal Central Hospital. They were 28 men and 18 women, aged from 21 to 85 years (mean, 55.6 years). There were 34 pelvic ring fractures, 9 acetabular fractures and 3 combined pelvic ring and acetabular fractures. After the anterior lateral spine of pubic tuberosity was drilled by a guide pin and drill bit as the entry point, a reverse guide wire was knocked into the bone lightly by a hammer. For each retrograde intramedullary screwing into the acetabular anterior column, we recorded operation time, fluoroscopic frequency, and attempts to establish an acceptable screw pathway by the guide pin. The accuracy of screwing and the quality of fracture reduction were evaluated by imaging examination. For each patient, we recorded fracture union time and complications. Functional recovery of the pelvis and acetabulum was assessed by postoperative physical examination at the last follow-ups. Results The operation time of retrograde intramedullary screwing for the 46 patients averaged 28.9 minutes (from 16 to 55 minutes); the fluoroscopy frequency averaged 16.3 times (from 9 to 35 times); an acceptable screw pathway was established by the first attempt in 43 of the 46 patients (93.5%) and re-established after adjustment of the guide pin in the other 3. Forty patients were followed up for an average of 15.2 months(from 6 to 36 months). Postoperative CT scan and three-dimensional reconstruction showed that all the screws had been placed safely and accurately in the acetabular anterior column. Implant loosening and fracture displacement occurred in one case and lower limb thrombosis in another. No nail breakage, fracture nonunion, incision necrosis or infection, neurovascular injury or femoral head necrosis was observed. All fractures united after an average of 14.7 weeks (from 12 to 18 weeks). According to the Majeed scoring at the last follow-ups, the pelvic and acetabular function was evaluated as excellent in 29 cases, as good in 9, and as fair in 2, giving an excellent and good rate of 95.0%. Conclusion Hammering reverse guide wire technique is an effective method for safe placement of anterior column retrograde intramedullary screw in pelvic and acetabular surgery, because it can increase accuracy of screwing and reduce intraoperative radiation, operation time and incidence of complications though it is simple. Key words: Pelvis; Acetabulum; Fractures, bone; Surgical procedures, minimally invasive; Fracture fixation, internal

Directive function of intracavitary electrocardiogram bimodal P-wave in the position of PICC tip

Objective To determine the accuracy of intracavitary electrocardiogram bimodal P-wave and characteristic P-wave in the position of PICC tip. Methods In the process of ECG guided catheterization, the morphological changes of P-wave in the intracavitary electrocardiogram were observed, and the bimodal P-wave and characteristic P-wave were recorded. The corresponding catheter length of the bimodal P-wave and characteristic P-wave were recorded. CT three-dimensional reconstruction was performed on 416 patients who underwent CT examination before and after catheterization. The distance between carina of trachea to superior vena cava and the right atrium junction was measured as best position of PICC and the standard distance. After catheterization, the distance from the tip of catheter to the corresponding catheter length of the bimodal P-wave and characteristic P-wave was measured as actual distance, and compared with the standard distance. Results In 416 cases, 168 patients (40.38%) were bimodal P-wave, and the accurate rate of bimodal P-wave was 86.31%(145/416), and the accurate rate of the characteristic P-wave was 13.69% (23/416). The standard distance was (41.96±9.16) mm, the actual distance of corresponding characteristic P-wave was (48.00±15.18) mm and bimodal P-wave was (45.10±11.16) mm. The distance of bimodal P-wave to control was (1.31±0.33) mm and characteristic P-wave was (6.00±2.88) mm, which was significant statistical difference (t=5.197, P < 0.05), and the standard deviation of the distance of bimodal P-wave to control was smaller (0.33 < 2.88). Conclusions The intracavitary electrocardiogram bimodal P-wave is more accurate than characteristic P-wave in the position of PICC tip and it supplements and improves thePICC's tip position. Key words: Bimodal P-wave; Characteristic P-wave; Intracavitary electrocardiogram; PICC

Variation in pelvic shape and size in Eastern European males: a computed tomography comparative study.

BackgroundThe significantly accelerated development of human society in the last millennium has brought about changes in human behavior and body mass that may have influenced human bone morphology. Our objective was to analyze the variation in pelvic shape and size in males from modern and medieval populations.MethodsWe obtained 22 pelvic girdles of adult males from a medieval cemetery located in Cedynia, Poland. The control group comprised 31 contemporary male pelves from individuals inhabiting the same region. The analyzed parameters were: interspinous distance (ISD), intercristal distance (ICD), intertuberous distance (ITD), anatomic conjugate of the pelvis, height of the pelvis (HP), iliac opening angle (IOA), iliac tilt angle (ITA), and ISD/ITD/HP ratio. Geometric morphometrics was used to analyze differences in shape in the pelves. All analyses were carried out on three-dimensional CT reconstructions of pelves.ResultsISD, ICD, and IOA were significantly greater in modern pelves than in those from Cedynia, but no significant differences were seen between the two groups in ITD, anatomical conjugate, HP, or ITA. ISD/ITD/HP ratios were significantly lower in the Cedynia group. Geometric morphometrics revealed significant differences in pelvic shape between the analyzed groups.DiscussionThe pelves of modern males are larger, wider, and flatter than those of medieval males. Changes in the set of daily activities that produce mechanical loading and estimated body mass may constitute the main factors explaining pelvic variability. However, differences in ontogenesis should also be taken into consideration, especially since growth in past populations is often found to be reduced relative to modern populations.

The application of ultrasonic bone curette in laminoplasty of spinal canal after resection of intraspinal tumors

To explore the practicability and safety of ultrasonic bone curette in the laminoplasty of spinal canal after resection of intraspinal tumors. The clinical data of 17 patients with thoracolumbar intraspinal tumors treated with ultrasonic bone curette after resection of intraspinal tumors between December 2015 and April 2017 were retrospectively analyzed. All patients were male, aged 42-73 years with an average of 57.4 years. The disease duration was 2-47 months with an average of 21.1 months. Among them, there were 4 cases of thoracic intrathoracic tumors (T 10 in 1, T 12 in 3) and 13 cases of lumbar intrathoracic tumors (L 1 in 5, L 2 in 4, L 3 in 2, and L 4 in 2). Postoperative pathological diagnosis showed that 8 cases were schwannoma, 4 cases were meningioma, 2 cases were neurofibroma, 2 cases were dermoid cyst, and 1 case was ependymoma. Spinal nerve function was evaluated preoperatively according to Frankel classification criteria, with 2 cases of grade B, 7 cases of grade C, and 8 cases of grade D. During the operation, the time of single segmental vertebral canal posterior wall incision, the overall operation time, intraoperative blood loss, intraoperative dural injury, and cerebrospinal fluid leakage, spinal cord and nerve root injury were recorded. At 3-6 months after operation, the tumor and bone healing were observed according to MRI and CT three-dimensional reconstruction, and the spinal nerve function was evaluated by Frankel classification. The time of ultrasonic osteotomy for the posterior wall of a single segmental vertebral canal was 3.4-5.7 minutes, with an average of 4.1 minutes. The overall operation time was 135-182 minutes, with an average of 157.3 minutes. The intraoperative blood loss was 300-500 mL, with an average of 342.6 mL. There was no accidental dural injury, and cerebrospinal fluid leakage, nerve root injury, or spinal cord injury. The incision healed by first intention after operation. All the 17 patients were followed up 9-18 months, with an average of 12.7 months. MRI examination showed no tumor recurrence, and CT three-dimensional reconstruction showed good bone healing in all patients. During the follow-up, there was no loosening or rupture of the internal fixator and there was no re-compression of the spinal cord. At last follow-up, according to Frankel classification, there were 1 case as grade B, 5 cases as grade C, 7 cases as grade D, and 4 cases as grade E. The application of ultrasonic bone curette in laminoplasty of spinal canal after resection of intraspinal tumors can preserve the integrity of the bone ligament structure of posterior column, maintain the volume of vertebral canal, and has high safety, practicability, and good postoperative effectiveness.

Energy Evolution and Acoustic Emission Characteristics of Sandstone Specimens under Unloading Confining Pressure

The acoustic emission characteristics of rock specimens under different initial unloading confining pressures were tested to obtain the damage and rupture characteristics of the sandstone unloading confining pressure path. The CT scan and three‐dimensional reconstruction of the fractured rock specimens were carried out to study the differences of energy evolution and acoustic emission characteristics during the failure of sandstone under different initial unloading pressures. The results show that the unloading confining pressure has a significant influence on the deformation and failure of the rock. There is a significant yielding platform for the circumferential strain and the bulk strain at the peak of the unloading pressure. The larger the initial unloading pressure is, the greater the axial absorption strain energy, the dissipative energy, and the elastic strain energy are at the peak point. After the stress peak point, the elastic strain can be quickly converted into the dissipative energy for rock damage. The elastic energy released from the moment of rock failure under high confining pressure is more concentrated. The acoustic emission ringing and b value characteristic parameters of the rock have a good correlation with the internal energy evolution of the rock, which better reflects the progressive damage of the rock under low stress and the sudden failure of high‐stress unloading.

Anterior cervical ossified posterior longitudinal ligament en bloc resection for the treatment of cervical ossification of posterior longitudinal ligament

Objective To evaluate theclinical efficacy and safety of anterior cervical ossified posterior longitudinal liga-ment en bloc resection (ACOE), and analyze the advantages of ACOE compared to the traditionally anterior cervical surgery. Methods The clinical datawith more than one year follow-up of 96 patients suffered from cervical ossification of the posterior longitu-dinal ligament(OPLL) from April 2010 to March 2017 was retrospectively analyzed, including 57 males and 39 females, aged 32-69 years, average 54.6±8.7 years. There were 29 cases of nodular type (30.2%), 48 cases of segmental type (50.0%), 5 cases of con-tinuous type(5.2%), and 14 cases of mixed type (14.6%). The neurological function assessments before and after operation were performed using the Japanese Orthopaedic Association (JOA) scoring system and the visual analogue scale (VAS) scoring system.The effect of ossified mass resection was observed by three-dimensional reconstruction CT scan. The spinal cord decompression was evaluated by MRI. The cervical curvature was compared before and after surgery by cervical lateral radiograph. The operation time, intraoperative blood loss, recovery rates of the JOA scores and complication rates of this group were compared with the cases of anterior cervical ossified posterior longitudinal ligament piecemeal resection (ACOP) reported by the recent literature to analyze the clinical efficacy, safety and advantages of ACOE. Results All the surgeries of 96 cases were successfully performed, in-cluding 57 cases (59.4%) with subtotal resectionof single vertebra, 31 cases (32.3%) with subtotal resectionof doublevertebras, 1 case (1.0%) with expanded intervertebral decompression, 4 cases (4.2%) with + subtotal resection,1 case (1.0%) with semi-vertebra + vertebra + subtotal resection, 2 cases with double vertebras + semi-verte-bra subtotal resection (2.1%). Ninty-six cases were followed up for 12 to 78 months, with an average of 28.0±9.3 months. The preoperative JOA score with (11.38±2.80) scores was increased to 15.32±1.62 scores at the last follow-up, and the recovery rate of JOA score was 74.63%±13.18%. The preoperative VAS score with 6.00±1.41 scores was reduced to 2.35±1.11 scores at the last follow-up. The cervical curvature increased from 10.4°±9.0° before surgery to 15.8°±8.1° at the last follow-up. CT showed that the ossified masses of the surgical segments were completely excised without residue; MRI showed that the com-pressionsof spinal cords and dural sacs were completely relieved, with nice morphology recovery. There was no neurological de-terioration in this group. There were 6cases of cerebrospinal fluid leakage (CSFL), 3 cases of C5 nerve palsy, 1 case of Horner syndrome, 2 cases of dysphagia and hoarseness, 1 case of titanium mesh subsidence with screw loosing. At the final follow-ups, except one case of occasional throat foreign body sensation, the above complications were all remittedat different follow-up periods. Compared with the cases of ACOP reported by the recent meta-analysis, the operation time, the intraoperative blood loss, the complication rate of dysphagia with hoarseness and neurological deterioration were lower than those reported in the literature. The recovery rate of JOA scorewas higher than which reported in the literature. Conclusion ACOE is safe and effective for the treatment of cervical OPLL, which may be superior to traditional anterior cervical surgery in terms of surgical safe-ty, controllability of cerebrospinal fluid leakage and improvement of neurological function. Key words: Cervical vertebrae; Ossification of posterior longitudinal ligament; Decompression, surgical; Spinal fusion

Headless pressure screw with local complication of PRP for the treatment of intra-articular fracture of old metatarsal

To discuss clinical effects of headless pressure screw with local complication of PRP in treating old metatarsal intra-articular fracture. From January 2010 to June 2016, 7 patients with old metatarsal intra-articular fracture treated by open reduction headless compression screw internal fixation by local application PRP, including 5 males and 2 females, aged from 21 to 52 years old, 5 patients injured by falling down and 2 patients caused by crushing, the time from injury to operation ranged from 3 to 6 weeks. Preoperative anteroposterior, lateral and oblique X-ray film and three-dimensional CT reconstruction were examined, and the results showed 2 patients on the second metatarsal, 2 patients on the third metatarsal, 3 patients on the fourth metatarsal. Regular X-ray as postoperative examination was observed, and American Orthopaedic Foot and Ankle Society (AOFAS) ankle scoring system at the final follow-up was evaluated. Seven patients were followed up from 6 to 17 months. All incisions healed at stage I without joint stiffness, traumatic arthritis and related complications. Imaging examination showed fracture reached bone healing, healing time ranged from 3 to 6 months. No joint stiffness and traumatic arthritis occurred. One of seven patients occurred stiffness of metatarsophalangeal joints. AOFAS score increased from 40.5±4.2 before operation to 85.0±10.5 at 12 months after operation, and 4 patients got excellent results, 2 moderate and 1 poor. The active motion of metatarsophalangeal joint showed dorsal flexion ranged from 35° to 40°, plantar flexion ranged from 25° to 35°. Headless pressure screw with local complication of PRP in treating old metatarsal intra-articular fracture could recover articular surface of metatarsal head, improve metatarsophalangeal joints activity, which do not need the second operation, and could receive good clinical results with early exercise.

Application effects of CT angiography and three-dimensional reconstruction technique in repairing scar around the mouth and chin with expanded forehead axial flap

Objective: To explore application effects of CT angiography (CTA) and three-dimensional reconstruction technique in repairing scar around the mouth and chin with expanded forehead axial flap. Methods: From June 2013 to October 2017, 9 patients with hyperplastic scar around the mouth and chin after deep burns on face were admitted to our unit. The sizes of scars of patients ranged from 8 cm×7 cm to 13 cm×8 cm. One cylindrical skin soft-tissue dilator with nominal volume of 400 to 500 mL was implanted in forehead area of each patient. Five to six months after the dilator was implanted, scar around the mouth and chin was resected, and the dilator was removed. The secondary wound after scar resection was repaired by expanded forehead axial flap with bilateral superficial temporal vessel pedicles. Three of the nine patients received microstomia diorthosis at the same time. Before the operation, CTA and three-dimensional reconstruction were applied to obtain three-dimensional images of superficial temporal arteries and the branches in the donor site, which could identify the travel, adjacent location, and vascular anastomosis of the above-mentioned vessels to guide flap design. The sizes of flaps of patients ranged from 25 cm×9 cm to 30 cm×8 cm. Two to three weeks after the operation, flap pedicles were cut off, restored, and trimmed. The donor site was sutured directly. Ten to twelve days after the flap repair operation, the flap site received depilation treatment with semiconductor freezing point laser once a month for 4 to 6 times. Results: Flaps of all patients survived well, with no blood circulation disorder. The flaps of three patients were slightly bulky, while they were with natural appearance after flap thinning operation in 3 months post flap repair operation. During follow-up of 6 months to 2 years after the operation, color, texture, and thickness of the flaps were close to normal skin around scars. The appearance of perioral and mental region, and opening function of mouth improved significantly, with no recurrence of scar. Frontotemporal incision was hidden, hair on head grew normally, and reconstructed hairline was natural. Conclusions: Scar around the mouth and chin repaired with expanded forehead axial flap were with good appearance and function in operation area and good shape in donor site. CTA and three-dimensional reconstruction technique can provide clear three-dimensional images of superficial temporal arteries and the branches in expanded forehead axial flaps, which can provide reliable basis for preoperative designing of flap, reduce operative risk, and improve survival rate of flap, thus having clinical application value.