Application of digital technology in the reconstruction of orbital fractures: research progress / 中华创伤杂志

Orbital fracture often leads to facial collapse, diplopia, enophthalmos, and even blindness. Traditional surgery relies on the experiences of physicians to achieve fracture reduction and orbital wall reconstruction, but the repair effect is not satisfactory. In recent years, with the development of digital technology, technologies such as computer-assisted surgery, 3D printing, surgical navigation systems, and intraoperative CT imaging have become increasingly widespread in the field of orbital reconstruction. Such techniques can avoid dependence on physicians′ experiences and make it easy for estimating and positioning the implantation sites, which subsequently contributes to better surgery efficiency and precise reconstruction of the orbit, improving aesthetics and visual function of patients. To this end, the authors reviewed the recent progress in application of digital technology for orbital fracture reconstruction, so as to provide reference and theoretical basis for clinical practice.

Application of computer navigation technique in the treatment of complex orbital fractures / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To evaluate the efficacy and utility of computer navigation technique in the treatment of complex orbital fracture.<p>METHODS: A retrospective review of 19 patients with complex orbital fractures were conducted. They underwent the reconstructive surgery assisted by image-data-based computer navigation. The pre- and postoperative data of enophthalmos, eyeball movement, diplopia, infraorbital numbness, and orbit CT image were recorded and analyzed. <p>RESULTS: The processes of pre-operation planning and intraoperative navigation were successful. During the 6 to 18mo postoperative follow-up, enophthalmos was completely corrected in 14 cases, while 5 patients had slight residual enophthalmos. Eyeball movement restriction was completely corrected in 7 cases, and was also improved in 3 cases. Diplopia was disappeared in 10 patients and improved in 2 patients, but still maintained in 1 patient postoperatively. Infraobital numbness was found in 4 cases, and dissappeared in 6mo postoperatively. No serious complications such as optic nerve lesion and vision loss were observed. Postoperative CT scans demonstrated that the fractures were corrected in all cases. The accuracies of the surgeries were satisfying. <p>CONCLUSION: Computer navigation system is a safe and effictive technique in assisting diorthosis in complex orbital fracture.

Computer navigation-assisted surgical treatment with osteotomy for upper thoracic kyphosis / 中国组织工程研究

BACKGROUND: The biomechanical characteristics of kyphosis of the upper thoracic vertebra are unique. Decompression and internal fixation are relatively difficult. Previous relevant studies and case reports are few, and there is a lack of research on correction of kyphosis of the upper thoracic section with the assistance of computer navigation. OBJECTIVE: To explore the clinical effect of computer navigation-assisted surgical treatment of upper thoracic kyphosis by screws and osteotomy. METHODS: Totally 18 patients with kyphotic deformity of the spine (T1-T4) were admitted in Beijing Jishuitan Hospital from June 2011 to June 2018, including 11 males and 7 females, aged 12 to 59 years. They were all treated with computer-assisted surgical treatment with PSO osteotomy. Local Cobb angle of the upper thoracic kyphosis was determined during final follow-up. Cervical visual analogue scale, Nurick grades, EMS scores and satisfaction of the surgery were evaluated. This study was approved by the Ethics Committee of Beijing Jishuitan Hospital (approval No. 201709-23). RESULTS AND CONCLUSION: (1) A total of 18 patients were followed up for 6-90 months at an average time of (33. 73±35. 33) months. (2) The local Cobb angle of 18 patients at the last follow-up was significantly improved [(47. 32±9. 92)°, (24. 01 ±7. 64)°, P < 0. 001]. Cervical visual analogue scale score at the last follow-up was significantly lower than that before surgery (3. 64±2. 16, 0. 73±1. 01, P< 0. 001). Nurick score at the last follow-up was significantly lower than that before surgery (2. 91 ±0. 94, 0. 82±1. 47, P < 0. 001). EMS score at the last follow-up was significantly higher than that before surgery (14. 45±0. 93), 17. 09±1. 45, P< 0. 001). (3) Surgical satisfaction was excellent (n=16) or good (n=2). (4) At the last follow-up, 18 patients had no adverse reactions related to implants, and the wound healed well without screw loosening. (5) The results showed that reasonable osteotomy correction with computer-assisted surgery and PSO osteotomy could effectively treat kyphosis of upper thoracic segment.

Navigated Pin-Point Approach to Osteoid Osteoma Adjacent to the Facet Joint of Spine

Osteoid osteoma (OO) is a benign osteoblastic tumor. Its curative treatment is complete removal of the nidus, where intraoperative localization of the nidus governs clinical results. However, treatment can be difficult since the lesion is often invisible over the bony surface. Accordingly, establishment of an ideal less invasive surgical strategy for spinal OO remains yet unsettled. We illustrate the efficacy of a computed tomography (CT)-based navigation system in excising OO located adjacent to the facet joint of spine. In our 2 cases, complete and pin-point removal of the nidus located close to the facet joint was successfully achieved, without excessive removal of the bone potentially leading to spinal instability and possible damage of nearby neurovascular structures. We advocate a less invasive approach to spinal OO, particularly in an environment with an available CT-based navigation system.

Intra-operative three-dimensional computer navigation system assisted free vascularized fibular grafting for the treatment of osteonecrosis of the femoral head / 中华显微外科杂志

Objective To evaluate the feasibility,technique and preliminary clinical results of the intraoperative three-dimensional (3-D) computer navigation system assisted free vascularized fibular grafting for the treatment of osteonecrosis of the femoral head.Methods From October 2010 to April 2013,14 patients (18 hips) with osteonecrosis of the femoral head were treated by free vascularized fibular graft transfer,assisted by intraoperative3-D computer navigation system.Of 18 hips,8 were classified as stage Ⅱ ;6 as stage Ⅲ,4 as stage Ⅳ according to Steinberg system.The entire procedures were visualized and guided by the 3-D navigation system,including location of optimal entry point,exploration of the field,excision of the necrotic bone tissues,and the fibular grafting transfer with vessel anastomosis.The follow-up records included the results of X-ray,the Harris score of the hip,and the complications.Results Operations of all 14 patients (18 hips) were smooth and successful with patent vessel and umcompromised grafts evidenced by ECT scan at day 7 postoperatively.Postoperative X-ray confirmed the complete eradication of necrotic focuses with surrounding calcified bone and the accurate positioning of fibular grafts.The mean follow-up period was 23.6 months (8-29 months).Harris scores significantly improved from 57.5 ± 14.5 before operations to 87.5 ±2.5 after,with 6 hips' scores classified as Excellent,and 11 as Good.X-ray obtained more than 1 year after operation suggested improvement was achieved in 15 hips.Conclusion Intraoperative 3-D computer navigation system has multiple merits in assisting free vascularized fibular grafting for the treatment of osteonecrosis of the femoral head,including clear anatomic structure,better accuracy,less damage,and reliable functional recovery,which imply it is a highly applicable approach.

Computer-assisted C1-C2 Transarticular Screw Fixation "Magerl Technique" for Atlantoaxial Instability

STUDY DESIGN: A retrospective study. PURPOSE: To evaluate the surgical results of computer-assisted C1-C2 transarticular screw fixation for atlantoaxial instability and the usefulness of the navigation system. OVERVIEW OF LITERATURE: We used a computed tomography (CT)-based computer navigation system in planning and screw insertion in Magerl's procedure, which provides the most rigid atlantoaxial fusion, to avoid risk of vertebral artery (VA) tear by avoiding high-riding VA during screw insertion. METHODS: Twenty patients who underwent atlantoaxial fusion under the CT-based navigation system were studied. The mean observation period was 33.5 months. The evaluated items included the existence of VA stenosis by preoperative magnetic resonance angiography, surgical time, blood loss volume, Japanese Orthopaedic Association (JOA) score and Ranawat's pain criteria before surgery and at final follow-up, postoperative screw position evaluated by CT, and bony fusion. RESULTS: The mean operation time was 205 minutes, with the mean blood loss volume of 242 ml. The mean JOA score was 11.6 points before surgery and 13.7 at final follow-up. Occipital and/or cervical pain presented before operation was remitted or resolved in all patients. Evaluation of screw insertion by CT revealed correct penetration to atlantoaxial joints, with a perforation rate of 2.6%. There was no complication, including VA tear, and all patients who were followed-up during one year or more after surgery achieved bony fusion. Some subjects who appeared inappropriate for surgery from CT images were assessed as eligible for surgery based on the evaluation results obtained using the navigation system. CONCLUSIONS: It was demonstrated that the CT-based navigation system is an effective support device for Magerl's procedure.

A Computer Navigation System Analysis of the Accuracy of the Extramedullary (Tibial) Alignment Technique in Total Knee Arthroplasty (TKA)

In total knee arthroplasty, mechanical alignment guides have improved the accuracy of implant alignment, but errors are not uncommon. In the present study, an image free computer assisted navigation system was used to analyse the accuracy of an extramedullary (tibial) alignment system, which is based on predetermined, fixed anatomical landmarks. Comparisons were made between two surgeons, with different levels of competency in order to determine if experience affected the accuracy of extramedullary tibial

An Analysis of the Relationship between the Morphometry of the Distal Femur, and Total Knee Arthroplasty Implant Design

Current available implants for total knee replacement are based on the mormphometry of the Caucasian knee. We believe there are significant morphometric differences in the Asian knee that will be relevant in future implant designs. Sixty nine consecutive patients (80 knees) underwent computer navigated primary total knee arthroplasty. The anterior posterior (AP) length, and the medial lateral (ML) width of the distal femur, were analyzed, with respect to the final sizing details of four implants (femoral component) commonly used locally. The mean AP length was 59.9 (SD 4.8) mm, and the mean ML width was 65.0 (SD 5.0) mm. The overall mean aspect ratio (ML/AP) was 1.09 (SD 0.07). The mean aspect ratio for females was 1.08 (SD 0.07). Both were smaller than the aspect ratio of the implants which ranged from 1.11 to 1.13. All four implants tend to overhang at the medial lateral width of the distal femur. This is more obvious in females. Future implant designs should provide more ML wdth sizes for a given AP length, in addition to gender differences, for ths population.

Computer-navigation assistance in arthroscopic reconstruction of anterior cruciate ligament / 中华创伤骨科杂志

Objective To compare traditional arthroscopic reconstruction of anterior cruciate ligament (ACL) and the arthroscopic ACL reconstruction assisted by fluoroscopy-based navigation system in accuracy and reproducibility of the tunnel placement. Methods Fluoroscopy-based navigation system was used in 40 cases of arthroscopic ACL reconstruction from December 2005 to March 2006. Another 40 cases of traditional arthroscopic ACL reconstruction performed between June 2005 and March 2006 were used as control. The positions of the femoral and tibial tunnels were measured on their radiograms and compared statistically. Results The femoral tunnel position measurements averaged 62. 3%?5. 6% (52% - 73% ) in navigation-assisted ACL reconstruction, and 56. 6%?7. 3% (46% - 77% ) in the traditional arthroscopic operation. The tibial tunnel position measurements averaged 45.4%?3. 8% (37%-53% ) in the navigation-assisted ACL reconstruction, and 41. 1%?6. 0% (25% - 54% ) in the traditional arthroscopic operation. The differences were statistically significant ( P

Fixation assisted by computer navigation for spinal fracture and instability / 中华创伤骨科杂志

Objective To discuss application of initiative infrared ray computer assisted 3D navigation system in spinal complex operation to improve surgical safety. Methods From December 2002 to July 2004, we performed 90 cases of spinal operation assisted by computer 3D navigation system. There were 38 cases of spinal fractures, and 236 cases of pedicle fixation. In lumbar spine surgery, fluoroscopy was commonly used, because the pedicle of lumbar spine was thick enough. 3D computer navigation was used in the other cases. Results 4 screws (1.7%) were not in good position, and the position error rate was 0.23 to 0.56 mm (automatically calculated by the computer). But we had once performed 272 cases of fixation with cervical pedicle screws just assisted by G arm or C arm fluoroscopy, 29 (10.7%) of which were not in good position. Conclusion In comparison, computer navigation assisted operation can make pedicle screw positioning more correct.