Complete Remission of Metastatic Duodenal Neuroendocrine Carcinoma Treated with Chemotherapy and Surgical Resection / 대한췌담도학회지

A 57-year-old male with periampullary duodenal mass was diagnosed as grade 3 duodenal neuroendocrine carcinoma with multiple liver metastasis. After nine cycles of cisplatin and etoposide, abdominal computed tomography (CT) findings showed complete regression of primary duodenal mass with marked size reduction of liver metastasis. Positron emission tomography findings showed metabolic complete response in both duodenal and liver mass. Pylorus-preserving pancreaticoduodenectomy was done and pathologic finding showed 5 mm sized remnant neuroendocrine tumor. The patient has remained alive with no evidence of disease for 43 months after initial diagnosis. This case suggests the possibility of heterogeneous nature of grade 3 neuroendocrine carcinoma and selected population may have extreme sensitivity to cisplatin and etoposide chemotherapy leading to complete response.

Indirect Decompression using Segmental Screw Fixation for Cervical Myelopathy Caused by C1-2 Subluxation: Technical Note / 대한정형외과학회잡지

The main aims of surgery for severe cord compression and myelopathy caused by atlantoaxial subluxation are decompression of the spinal cord and achievement of rigid fixation and fusion. Direct decompression by resecting the bony structures that compress the spinal cord includes transoral decompression and resection of the posterior arch of the atlas. The shortcomings of these procedures are a high complication rate and a relatively low rate of union. Indirect decompression can be performed by a reduction of the subluxation and fixation without bone resection. To the best of our knowledge, there are no domestic reports on the use of indirect decompression for severe cord compression and myelopathy for atlantoaxial subluxation. We report a case of a patient that had atlantoaxial subluxation and severe myelopathy; satisfactory reduction of the subluxation and decompression with an improvement in the myelopathy symptoms was achieved by indirect decompression using segmental screw fixation.

Atlantoaxial Fixation using C2 Subarticular Screws and C1 Lateral Mass Screws : A Technical Report / 대한정형외과학회잡지

Segmental screw fixation is a useful procedure for the surgical treatment of atlantoaxial subluxation. Currently, C1 lateral mass screws and C2 pedicle screws are the standard screws used in this procedure. However, the C2 pedicle screw can cause serious complications such as vertebral artery injury. Recently we suggested a new trajectory for the C2 screw, the subarticular screw, which has a lower probability of vertebral artery injury compared with the pedicle screw, based on a study using 1 mm-sliced CT scan images and simulation software. We report the first case of segmental screw fixation using C2 subarticular screws along with C1 lateral mass screws. The patient had atlantoaxial subluxation and myelopathy and showed satisfactory results after surgery.

The Subarticular Screw: a New Trajectory for the C2 Screw / 대한척추외과학회지

STUDY DESIGN: Surgical simulation using CT images and computer software. OBJECTIVES: We wanted to determine a new trajectory for the C2 screw, and then we wanted to evaluate its safety and accuracy. Summary of Literature REVIEW: There have been a few suggestions for trajectories of the C2 pedicle screws. However, their safety is somewhat unsatisfactory as all of them have some possibility of vertebral artery injury. MATERIALS AND METHODS: Using 1 mm-sliced CT scan images of 158 patients and an A-view spine surgery simulator 1.0, we determined a new trajectory for the C2 screw with which 4.0 mm screws can be inserted with a minimal number of breaches of the bone cortices. The percentage of cortical perforations by the suggested trajectory was compared with that by the pedicle screws by means of simulation. RESULTS: The medial angulation of the determined trajectory is the same as that of the pedicle on the axial CT images: it usually is between 30 and 40 degrees. The screw is angled toward the antero-superior end of the superior articular process of C2, as observed on lateral fluoroscopy. The entry point is 3 mm inferior to the posterior aspect of the superior articular surface, and this point should allows the screw (ED note: check this and it wasn't clear.)the screw to be inserted close to the superomedial border of the superior articular process. Using this trajectory, 2.5% (8/316) of the screws breached the vertebral grooves, while 6.0% (19/316) of the pedicle screws breached them (p=0.030, chi-square test). CONCLUSIONS: The subarticular screw has improved safety compared with the pedicle screws. However, there are still some casesin which screws can not be inserted without breaching the vertebral groove. Therefore, preoperative thin-slice CT scanning with three-dimensional reconstruction and/or three-dimensional CT-angiography is recommended.

Two Simple Tests for Adequate Needle Positioning in Vertebroplasty / 대한척추외과학회지

STUDY DESIGN: We analyzed the diagnostic values of two simple tests for adequate needle positioning in vertebroplasty. OBJECTIVES: We wanted to suggest performing the aspiration test and patency test, which can replace some of the roles of intraosseous venography (IOV) in vertebroplasty, and we also wanted to analyze the two tests' diagnostic values. SUMMARY OF LITERATURE REVIEW: Intra-osseous venography is an existing safety test for vertebroplasty, but it is less frequently performed nowadays because of its drawbacks. MATERIALS AND METHODS: The aspiration test is defined as positive if blood is easily aspirated through a vertebroplasty needle, and a positive aspiration test means that the needle tip is communicating with the venous system. This and IOV were carried out on a total of 114 sides of 61 vertebrae of 40 consecutive patients. Agreement between the two tests was evaluated with using Cohen's kappa coefficient, and the diagnostic values of the aspiration test, with using IOV as the gold standard, were also evaluated. The patency test is done in the intra-vertebral vacuum cleft cases. After bipedicular insertion of needles, saline is injected into one needle. If the saline gushes out of the other needle, the test is positive, and it means that both needles are inserted in the vacuum cleft. The patency test was performed in 25 vertebrae, and the positive rate and causes of the negative result were investigated. RESULTS: Cohen's kappa coefficient between the aspiration test and IOV was 0.88. The sensitivity of the aspiration test was 88%, the specificity was 99%, the positive predictive value was 97%, and the negative predictive value was 93%. The patency test was positive in 88% of the vacuum clefts. In all the positive cases, both needles were located within the vacuum cleft. In all the negative cases, one of the two needles was located outside the cleft. CONCLUSIONS: The aspiration test is a simple and reliable test that has high agreement with IOV. The patency test can be a better choice than IOV for the vacuum cleft cases because it does not leave contrast media in the clefts.

Efficacy of the Preventive Abduction Brace in Dementia Patients After Bipolar hemiarthroplasty of the Hip

Purpose: To evaluate the efficacy of the preventive abduction brace in dementia patients after bipolar hemiarthroplasty of the hip. Materials and Method: A review of 30 patients who had dementia prior to bipolar hemiarthroplasty of the hip. 20 females and 10 males were evaluated and their mean age was 80.4 years old (range, 68 to -92 years old). The average MMSE-K in dementia patients was 14.2 (range, 8 to 20). The reasons for the bipolar hemiarthroplasties were femoral neck fractures in all the cases. We analyzed the dislocation rates of those who had preventive abduction braces applied prospectively. Results: The average follow-up period after hemiarthroplasty was 2.2 years. All 30 patients had preventive abduction braces and no dislocations occurred after the bipolar hemiarthroplasties. Conclusion: Hip dislocations were not detected in those patients who preventive abduction braces applied. The present findings suggest that having a preventive abduction brace will definitely reduce the dislocation rate in dementia patients who have difficulties with rehabilitation after their operations.

C1-2 Fixation Using Polyaxial Screws and Rods Assisted by Computer Simulation for Revision of Failed Posterior Fusion: A Technical Report / 대한정형외과학회잡지

Segmental C1-2 screw fixation using C1 lateral mass screws and C2 pedicle screws is a technically demanding procedure which can cause injuries to the vertebral artery or neural structures as well as massive bleeding from the epidural venous plexus. In particular, this procedure is more difficult in revision cases because of the lack of normal anatomical landmarks, adhesion, and bleeding. The authors report a case of a patient in whom preoperative surgical simulation and planning using computer software was very helpful in the direct screwing of the atlas and axis for a revision of atlantoaxial fusion.

Diagnosis of Lumbar Lateral Disc Herniation: Value of Magnetic Resonance Imaging Revisited / 대한척추외과학회지

STUDY DESIGN: We retrospectively evaluated the value of magnetic resonance imaging (MRI) in the diagnosis of lumbar lateral disc herniations. SUMMARY OF LITERATURE REVIEW: MRI is known to be a reliable study for the diagnosis of a lumbar disc herniation. However, recent studies of its diagnostic value for lateral disc herniation have been rare. OBJECTIVES: We aimed to assess the diagnostic value of simple MRI, to determine the need for additional imaging studies and to investigate mimicking lesions. MATERIALS AND METHODS: In a lateral herniation group composed of 21 cases, including 10 foraminal and 11 extraforaminal herniations, the diagnostic value of simple MRI was evaluated, and the potential requirement for additional studies investigated. In a mimicking lesion group(5 cases), the entity of each lesion was identified. RESULTS: All 10 foraminal disc herniation cases were able to be confirmed with simple MRI, six of which were confirmed using sagittal images alone. In contrast, for the eleven extraforaminal disc herniations, sagittal MR images were not at all helpful in the diagnosis; however, six(55%) were confirmed from axial images, but the other five could not be confirmed until additional studies, such as enhanced MRI(4 cases), 1 mm-sliced CT (1) and CT-discography (3), were carried out. All 5 mimicking lesions were upper endplates of the lower vertebrae. CONCLUSIONS: Simple MRI is useful in the diagnosis of foraminal herniations, but not so helpful for extraforaminal herniations; particularly, sagittal images are of little use. Therefore, whenever a patient complaining of severe radiating pain presents with no causative finding on simple MRI, the extraforaminal regions on the axial images should be diligently scrutinized again, and additional studies considered when necessary. Conversely, mimicking lesions, such as an upper endplate, should be differentiated when a lateral disc herniation is suspected.

Development and Accuracy Test of a Robot-arm Type Image-guided Surgery System for Percutaneous Screw Fixation of the Sacro-iliac Joint

PURPOSE: To develop a robot-arm type image-guided surgery system for percuatneous screw fixation of the sacro-iliac joint and to evaluate its accuracy. MATERIALS AND METHODS: We have developed an image-guided surgery system using a three-dimensional digitizer (Microscribe 3-D G2, Immersion, USA) and a personal computer. The registration error and target localization error at fiducial registration were measured 30 times for each using a phantom made with plastic pelvic bone model (Sawbones, USA). Sixteen 6.5 mm cannulated screws were inserted into four plastic bone models, and the accuracy was evaluated. RESULTS: The target localization error was 1.46+/-0.47 mm while the registration error was 0.73+/-0.23 mm. All of the 16 screws were inserted well across the sacro-iliac joint, and there was neither cortical breach nor collision between screws or washers. CONCLUSION: The accuracy of the developed system was similar to that of optical tracker-based navigation systems, and its helpfulness and usefulness was proven with simulation surgery using plastic bone models.

The Prevalence of Shoulder Pain in Adults over 40 years old in Rural Area of Chonan City / 대한정형외과학회잡지

PURPOSE: To determine the prevalence of shoulder pain and pain degree in a population exceeding 40 years of age in a rural area of Chonan, Korea, and to correlate those data with other countries general population. MATERIALS AND METHODS: Two hundred and fifty three people (over 40 years old) who received a free medical examination. There were 93 men and 160 women with an average age of 65 years (range, 40 to 88 years). Patients were assessed in terms of pain degrees and shoulder function using the standard method of the Research Committee of American Shoulder and Elbow Surgeons (ASES). RESULTS: One hundred and ten (43%) people reported shoulder pain and 83 (33%) complained of night pain, Thirty-five percents (33/93) of men and 48% (77/160) of women had shoulder pain. Average pain degree was 2.1 (range: 0-10) in general, 1.6 (range: 0-10) in male and 2.5 (range: 0-10) in female for shoulder pain, respectively. CONCLUSION: Shoulder pain can occur in all age groups, however, more aggressive preventive and therapeutic programs should be considered in the elderly.