ABSTRACT
BACKGROUND: The treatment of upper cervical spine disorders through a posterior pedicle fixation approach have been carried out in some domestic large hospitals, but this surgery is still considered as a difficulty of cervical spine surgery. In order to minimize the risk of surgery, the authors designed a program of individual operations, and combined with self-developed pedicle locating and directing speculum to determine precise intraoperative position of pedicle screws, and no report is found by searching related database in China.OBJECTIVE: To improve the one-time success rate of internal fixation screws, to investigate the biomechanical effect of the implant, to formulate a simple, practical, individual protocol for atiantoaxial pedicle screw-plate system based on related data. METHODS: A total of 31 patients were recruited from Department of Orthopaedics in the 251 Hospital of Chinese PLA, between January 2002 and September 2006. Under the guidance of self-made atlantoaxial locating and directing speculum, the entrance point and angle for screw insertion, as well as screw diameter and length were determined according to the results of X-ray and CT measurement. Atlas pedicle screw was inserted at left (19.93±1.32) mm, and right (19.16±1.3) mm; Atlas pedicle screw insertion angle to inside was left (23.72±2.09)°, and right (23.35±1.91)°; Atlas pedicle screw insertion angle to side of head was (9.00±1.20)°. Axis pedicle screw was inserted at left (13.14±0.82) mm, and right (13.85±0.79) mm; Axis pedicle screw insertion angle to inside was left (24.52±1.26)°, and right (20.42±1.42)°; Axis pedicle screw insertion angle to side of head was (25.00±3.00)°.RESULTS AND CONCLUSION: ①Totally 124 pedicle screws were implanted into 31 patients, and 122 screws were of one-time success. The precision rate was 98.39%. Two screws were secondly inserted because of cutting lateral cortical bone of pedicle for deviation of inward angle. ②Occipital neuralgia was found in 2 cases postoperatively and cured after one month of treatment;screws penetrated atlas left vertebral lateral wall in 2 cases, no spinal or vertebral artery injury was found. ③Radiographs showed that atlas was completely reduced in all patients, and apposition of dentoid process of axis fracture was good. CT films showed the screws a good location to the vertebrarterial spinal cord. ④The follow-up visit was averaged of 10.5 months. Bony fusion was found in all patients. No screw-plate breakage was found. No inflammatory or rejection reactions occurred.⑤By JOA scale, there were 16 cases of excellent, 12 cases of good, 2 cases of fine, and 1 case of poor. The excellent and good rate was 90%. It is suggested that the success rate of atlantoaxial pedicle screw-plate mplantation can be improved through a biomechanical angle.
ABSTRACT
BACKGROUND:The anatomic structures and kinetic characteristics are the bases to establish hand model, and the kinetic characteristics of hand are determined by the anatomic structure. So, numerous scholars have paid close attention to virtual hand models based on the anatomic structures of hand.OBJECTIVE: To construct visible hand model based on anatomic structure.DESIGN: Single sample trial.SETTING: Center Laboratory, Third Military Medical University of Chinese PLA.MATERIALS: This trial was carried out in the Center Laboratory, Third Military Medical University of Chinese PLA in October 2003. Two fresh adult hands, which involved wrist joint, provided by the Department of Anatomy, Third Military Medical University of Chinese PLA, were employed. The two hands had no organic damage by naked observation.METHODS: The specimens were embedded and mill-cut (mill-cut layer thinness 0.2 mm). Cannon (ESO 1OD) digital camera (6.3 million pixel) was used for image collection. Each image was 31.5 MB, Data of 1 200 images were obtained.Adobe Photoshop 7.0 software was used for image treatment and then two-dimensional cross-section images were collected. The bone, flexor tendon and the outline of hand was three-dimensionally reconstructed by using the software,which was developed by the Department of Computer Science and Technology,Tsinghua University and Institute of Computer Medicine, Department of Anatomy, Third Military Medical University of Chinese PLA.MATN OUTCOME MEASURES: Three-dimensional reconstruction of the bone, flexor tendon and outline of hand.RESULTS: ①The outline of hand: After being reconstructed, the outline, which consisted of all fingers and nails, was well displayed, and observed from many directions.② Three-dimensional reconstruction of the bone of hand: The reconstructed bones of hands involved digital bones, metacarpal bones, carpal bones and all joints, and they could be displayed solely or in groups with other reconstructed structures.③ Three-dimensional reconstruction of the flexor tendons of hand:Four superficial flexor tendons, four deep flexor tendons and one flexor pollex Iongus muscle tendon could be seen from the reconstructed images. All the flexor tendons went out together from the carpal canal and went through the palm, then spread out in fan-shape along the direction of each finger. ④ Three-dimensional reconstruction of the metacarpal fascial spaces: It could be observed from the reconstructed three-dimensional models that the proximal end of the thenar space was close, its distal end was open to the 1st web space, and the proximal end of the midpalmar fascial space was open to the posterior space of antebrachial flexor by carpal canal. Its distal end had three little spaces, which were open to the 2nd, 3rd and 4th web space, respectively.CONCLUSION: The visible hand model, which is preliminarily established, can precisely show the main anatomic structure of palm.
ABSTRACT
BACKGROUND: The metacarpal fascial spaces of hand are the potential structure that is not virtual, so that difficulties are presented in diagnosis and treatment of diseases of the metacarpal fascial spaces of hand. In order to solve the difficulties,anatomical borderline and abut relationship of the metacarpal fascial spaces of hand have to be sufficiently understood. OBJECTIVE: The borderline and abut of the metacarpal fascial spaces of hand were detailedly observed and researched by fresh cadaveric dissection, thin sectional anatomy and computer image recognition technology, and the 3-D reconstruction technology was utilized to reconstructed the metacarpal fascial spaces in this paper, so the abut relationship of the metacarpal fascial spaces of hand could be displayed, and the detailed anatomical data of imaging diagnosis and surgical treatments of disease of the fascial spaces of hand could be provided. DESIGN: Repeated measuring design.SETTING: The 251 Hospital of Chinese PLA and Central Laboratory of the Third Military Medical University of Chinese PLA. MATERIALS: Twelve adult fresh cadaveric hands which involved six right hands and six left hands and wrist joint, had no organic damage by naked observation, provided by the Department of Anatomy, the Third Military Medical University of Chinese PLA, among one right hand and one left hand were waiting for being mill-cut and thin cross-section dissected and imaging reconstructed. Among ten hands were observed by fresh cadaveric anatomy. METHODS: The trial was carried out in the 251 Hospital of Chinese PLA and Central Laboratory and Department of Anatomy of the Third Military Medical University of Chinese PLA from May 2003 to February 2006. Based on the gross anatomy, thin cross-section anatomy, visible human and virtual human technology theory, the metacarpal fascial spaces of hand were three-D reconstructed in microcomputer.MAIN OUTCOME MEASURES: Anatomical borderline and about relation of the metacarpal fascial spaces of hand. RESULTS: Display of observation result of adjacent and dimension of the midpalmar space and the thenar space by fresh cadaveric anatomy combined with thin cross-section anatomy, computer image recognition technology, and the 3-D reconstruction technology: The anterior borderline of the MPS was the digital flexor tendons of middle finger, ring finger, little finger and the 2nd lumbrical muscle (LM), 3rd LM, 4th LM; the posterior borderline was the palmar interosseous fascia before 3rd palmar bone, 4th palmar bone, 5th palmar bone and corresponding interosseous muscles; the lateral borderline was the palmar intermediate septum; the medial borderline of the MPS was the medial intermuscular septum of palm. In addition, the distal section of the MPS which was separated into three little spaces by two septums of connective tissue, and 3rd 4th, 5th digital flexor tendon and 2nd, 3rd, 4th LM were respectively contained by the three little spaces. The proximal of this space opened to the posterior space of antebrachial flexor by the carpal canal; the distal of this space opened to 2nd, 3rd, 4th web space (WS) by 2nd, 3rd, compartment of 4th LM, and continuously the dorsal subcutaneous space and the subaponeurotic space. The anterior borderline of the TS was the 1st digital flexor tendon and the 1st LM; the posterior borderline was the fascia of abductor pollicis; the medial borderline was the palmar intermediate septum (PIMS); the lateral borderline was the tenden sheath of flexor pollicis longus and the lateral intermuscular septum of palm. The distal of this space opened to 1st WS by compartment of the 1st LM, and continuously to the dorsal subcutaneous space and the subaponeurotic space; the proximal of the TS was close.CONCLUSION: The proximal of the thenar space is close, the distal section of the metacarpal fascial spaces is separated into three little spaces, and the computerized three-D renconstruction of the fascial spaces of hand can provide some guidance for imaging diagnosis and surgical treatments.