1.Computed Tomography-Based Occipital Condyle Morphometry in an Indian Population to Assess the Feasibility of Condylar Screws for Occipitocervical Fusion.
Abhishek SRIVASTAVA ; Geetanjali NANDA ; Rajat MAHAJAN ; Ankur NANDA ; Nirajana MISHRA ; Srinivasa KARMARAN ; Sahil BATRA ; Harvinder Singh CHHABRA
Asian Spine Journal 2017;11(6):847-853
STUDY DESIGN: A retrospective computed tomography (CT)-based morphometric study of 82 occipital condyles in the Indian population, focusing on critical morphometric dimensions with relation to placing condylar screws. PURPOSE: This study focused on determining the feasibility of placing occipital condylar screws in an Indian population using CT anatomical morphometric data. OVERVIEW OF LITERATURE: The occipital condylar screw is a novel technique being explored as one of the options in occipitocervical stabilization. Sex and ethnic variations in anatomical structures may restrict the feasibility of this technique in some populations. To the best of our knowledge, there are no CT-based data on an Indian population that assess the feasibility of occipital condylar screws. METHODS: We measured the dimensions of 82 occipital condyles in 41 adults on coronal, sagittal, and axial reconstructed CT images. The differences were noted between the right and left sides and also between males and females. Statistical analysis was performed using the t-test, with a p-value of < 0.05 considered significant. RESULTS: Mean sagittal length and height were 17.2±1.7 mm and 9.1±1.5 mm, respectively. Mean condylar angle/screw angle was 38.0°±5.5° from midline, with mean condylar length and width of 19.6±2.6 mm and 9.5±1.0 mm, respectively. Average coronal height on the anterior and posterior hypoglossal canal was 10.8±1.4 mm and 9.0±1.4 mm, respectively. The values in females were significantly lower than those in males, except for screw angle and condylar width. Based on Lin et al.'s proposed criteria, eight of 82 condyles were not suitable for condylar screws. CONCLUSIONS: Preliminary CT morphometry data of the occipital condyle shows that condylar screws are anatomically feasible in a large portion of the Indian population. However, because a small number of population may not be suitable for this technique, meticulous study of preoperative anatomy using detailed CT data is advised.
Adult
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Female
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Humans
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Male
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Retrospective Studies
2.Morphometric Study of C1 Pedicle and Feasibility Evaluation of C1 Pedicle Screw Placement with a Novel Clinically Relevant Radiological Classification in an Indian Population.
Abhishek SRIVASTAVA ; Rajat MAHAJAN ; Ankur NANDA ; Geetanjali NANDA ; Nirajana MISHRA ; Vijayant KANAGARAJU ; Sahil BATRA ; Harvinder Singh CHHABRA
Asian Spine Journal 2017;11(5):679-685
STUDY DESIGN: A retrospective computed tomography (CT)-based morphometric study of 84 C1pedicles in an Indian population focusing on critical morphometric dimensions vis-a-vis C1 pedicle screw placement. PURPOSE: To determine the feasibility of C1 pedicle screw placement in an Indian population and propose a novel classification system for the same. OVERVIEW OF LITERATURE: At present, C1 pedicle screws are rarely used, and very few studies have focused on the feasibility of pedicle screw placement in terms of racial, gender, and ethnic variations in anatomical structures. There are no CT-based data on C1 pedicles that assess the feasibility of pedicle screw placement in the Indian population. METHODS: We measured C1 pedicle diameter on CT coronal scan images of 42 adult patients. Extramedullary height (EMH) and intramedullary height (IMH) were measured. We examined the differences between the right and left atlas pedicles and compared measures between males and females. These data were analyzed using significance tests. Based on the results, we propose a novel classification system, which we believe will help in determining the feasibility of C1 pedicle screw placement. RESULTS: Forty-two adult patients (84 pedicles) were examined. Average EMH and IMH were 4.48±0.91 and 0.86±0.77, respectively. Approximately, 32% of the C1 pedicles had bone thicknesses of <4 mm, 49% had IMH of <1 mm, and 38% had no pedicles. The average thickness in women was 4.21±0.93 mm, which was significantly thinner than that in men (4.73±0.81 mm, p=0.004). Right and left pedicles were not significantly different. CONCLUSIONS: Our data indicate that approximately one-third of the Indian population may not be suitable candidates for C1 pedicle screw placement. Caution should be exercised while placing type 1B and type 2 pedicles based on our proposed classification system.
Adult
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Classification*
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Female
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Humans
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Male
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Pedicle Screws*
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Retrospective Studies
3.Comparison of Surgical Outcomes in Thoracolumbar Fractures Operated with Posterior Constructs Having Varying Fixation Length with Selective Anterior Fusion.
Hak Sun KIM ; Seung Yup LEE ; Ankur NANDA ; Ju Young KIM ; Jin Oh PARK ; Seong Hwan MOON ; Hwan Mo LEE ; Ho Joong KIM ; Huan WEI ; Eun Su MOON
Yonsei Medical Journal 2009;50(4):546-554
PURPOSE: Surgical treatment in the case of thoracolumbar burst fractures is very controversial. Posterior instrumentation is most frequently used, however, but the number of levels to be instrumented still remains a matter of debate. MATERIALS AND METHODS: A total of 94 patients who had a single burst fracture between T11 and L2 were selected and were managed using posterior instrumentation with anterior fusion when necessary. They were divided into three groups as follows; Group I (n = 28) included patients who were operated by intermediate segment fixation, Group II (n = 32) included patients operated by long segment fixation, and Group III (n = 34) included those operated by intermediate segment fixation with a pair of additional screws in the fractured vertebra. The mean follow-up period was twenty one months. The outcomes were analyzed in terms of kyphosis angle (KA), regional kyphosis angle (RA), sagittal index (SI), anterior height compression rate, Frankel classification, and Oswestry Disability Index questionnaire. RESULTS: In Groups II and III, the correction values of KA, RA, and SI were much better than in Group I. At the final follow up, the correction values of KA (6.3 and 12.1, respectively) and SI (6.2 and 12.0, respectively) were in Groups II and III found to be better in the latter. CONCLUSION: The intermediate segment fixation with an additional pair of screws at the fracture level vertebra gives results that are comparable or even better than long segment fixation and gives an advantage of preserving an extra mobile segment.
Adolescent
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Adult
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Child
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Female
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Humans
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Male
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Spinal Fractures/radiography/*surgery
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Thoracic Vertebrae/injuries/radiography/*surgery
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Treatment Outcome
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Young Adult
4.Video-Assisted Thoracoscopic Surgery Plus Lumbar Mini-Open Surgery for Adolescent Idiopathic Scoliosis.
Hyon Su CHONG ; Hak Sun KIM ; Nanda ANKUR ; Phillip Anthony KHO ; Sung Jun KIM ; Do Yeon KIM ; Jin Oh PARK ; Seong Hwan MOON ; Hwan Mo LEE ; Eun Su MOON
Yonsei Medical Journal 2011;52(1):130-136
PURPOSE: The objectives of this study are to describe the outcome of adolescent idiopathic scoliosis (AIS) patients treated with Video Assisted Thoracoscopic Surgery (VATS) plus supplementary minimal incision in the lumbar region for thoracic and lumbar deformity correction and fusion. MATERIALS AND METHODS: This is a case series of 13 patients treated with VATS plus lumbar mini-open surgery for AIS. A total of 13 patients requiring fusions of both the thoracic and lumbar regions were included in this study: 5 of these patients were classified as Lenke type 1A and 8 as Lenke type 5C. Fusion was performed using VATS up to T12 or L1 vertebral level. Lower levels were accessed via a small mini-incision in the lumbar area to gain access to the lumbar spine via the retroperitoneal space. All patients had a minimum follow-up of 1 year. RESULTS: The average number of fused vertebrae was 7.1 levels. A significant correction in the Cobb angle was obtained at the final follow-up (p = 0.001). The instrumented segmental angle in the sagittal plane was relatively well-maintained following surgery, albeit with a slight increase. Scoliosis Research Society-22 (SRS-22) scores were noted have significantly improved at the final follow-up (p < 0.05). CONCLUSION: Indications for the use of VATS may be extended from patients with localized thoracic scoliosis to those with thoracolumbar scoliosis. By utilizing a supplementary minimal incision in the lumbar region, a satisfactory deformity correction may be accomplished with minimal post-operative scarring.
Adolescent
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Child
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Female
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Humans
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Male
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Scoliosis/*surgery
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Thoracic Surgery, Video-Assisted/*methods
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Treatment Outcome
5.Video-Assisted Thoracoscopic Surgery for Correction of Adolescent Idiopatic Scoliosis: Comparison of 4.5 mm versus 5.5 mm Rod Constructs.
Hak Sun KIM ; Jin Oh PARK ; Ankur NANDA ; Phillip Anthony KHO ; Jin Young KIM ; Hwan Mo LEE ; Seong Hwan MOON ; Jung Won HA ; Eun Kyoung AHN ; Dong Eun SHIN ; Sung Jun KIM ; Eun Su MOON
Yonsei Medical Journal 2010;51(5):753-760
PURPOSE: The purpose of this study is to report the comparative results of thoracoscopic correction achieved via cantilever technique using a 4.5 mm thin rod and the poly-axial reduction screw technique using a 5.5 mm thick rod in Lenke type 1 adolescent idiopathic scoliosis (AIS). MATERIALS AND METHODS: Radiographic data, Scoliosis Research Society (SRS) patient-based outcome questionnaires, and operative records were reviewed for forty-nine patients undergoing surgical treatment of scoliosis. The study group was divided into a 4.5 mm thin rod group (n = 24) and a 5.5 mm thick rod group (n = 25). The radiographic parameters that were analyzed included coronal curve correction, the most caudal instrumented vertebra tilt angle correction, coronal balance, and thoracic kyphosis. RESULTS: The major curve was corrected from 49.8degrees and 47.2degrees pre-operatively to 24.5degrees and 18.8degrees at the final follow-up for the thin and thick rod groups, respectively (50.8% vs. 60.2% correction). There were no significant differences between the two groups in terms of kyphosis, coronal balance, or tilt angle at the time of the final follow-up. The mean number of levels fused was 6.2 in the thin rod group, compared with 5.9 levels in the thick rod group. There were no major intraoperative complications in either group. CONCLUSION: Significant correction loss was observed in the thin rod system at the final follow-up though both groups had comparable correction immediately post-operative. Therefore, the thick rod with poly axial screw system helps to maintain post-operative correction.
Adolescent
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Adult
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*Bone Screws
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Female
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Humans
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Male
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Retrospective Studies
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Scoliosis/radiography/*surgery
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Thoracic Surgery, Video-Assisted/*methods
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Treatment Outcome
6.Comparison between Operated Muscular Dystrophy and Spinal Muscular Atrophy Patients in terms of Radiological, Pulmonary and Functional Outcomes.
Hyon Su CHONG ; Eun Su MOON ; Hak Sun KIM ; Nanda ANKUR ; Jin Oh PARK ; Jin Young KIM ; Phillip Anthony KHO ; Seong Hwan MOON ; Hwan Mo LEE ; Nam Hun SEUL
Asian Spine Journal 2010;4(2):82-88
STUDY DESIGN: Retrospective comparative study. PURPOSE: To study and compare the surgical outcomes of muscular dystrophy (MD) and spinal muscle atrophy (SMA). OVERVIEW OF LITERATURE: There are few reports that have evaluated and compared the surgical outcomes of MD and SMA patients. METHODS: The patients (n = 35) were divided into two groups: a MD group with 24 patients and a SMA group with 11 patients. The average follow-up period was 21 months. All patients were operated for scoliosis correction using posterior instrumentation and fusion. In the immediate postoperative period, all efforts were made to reduce the pulmonary complications using non-invasive positive pressure ventilation and a coughing assist devices. The patients were evaluated by radiograph in terms of the Cobb's angle, pelvic obliquity, T1 translation, thoracic kyphosis and lumbar lordosis. The pulmonary function and self-image satisfaction were also assessed. RESULTS: There was a lower correction rate in the MD group (41.5%) than in the SMA group (48.3%), even though the curves were smaller in the MD group. The correction in the pelvic obliquity was significantly better in the SMA group (p = 0.03). The predicted vital capacity showed a 4% reduction in the MD group 1 year after surgery, while the SMA group showed a 10% reduction. The peak cough flow and end tidal PCO2 did not deteriorate and were well maintained. The average score for the improvement in self-image satisfaction postoperatively was 3.96 and 4.64 for the MD and SMA groups, respectively. The total complication rate was 45.7%; 14.3% of which were respiratory-related. CONCLUSIONS: Surgical intervention for MD and SMA may be performed safely in patients with a very low forced vital capacity (< 30%) through aggressive preoperative and postoperative rehabilitation efforts.
Animals
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Cough
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Follow-Up Studies
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Humans
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Kyphosis
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Lordosis
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Muscular Atrophy
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Muscular Atrophy, Spinal
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Muscular Dystrophies
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Positive-Pressure Respiration
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Postoperative Period
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Retrospective Studies
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Scoliosis
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Vital Capacity
7.Drug Eluting Stents in Infrapopliteal Arterial Disease: A Pilot Safety Study in an Asian Population.
Karthikeyan DAMODHARAN ; Ankur PATEL ; Farah Gillan IRANI ; Mark Christiaan BURGMANS ; Apoorva GOGNA ; Kiang Hiong TAY ; Richard Hg LO ; Chow Wei TOO ; Sum LEONG ; Nanda VENKATANARASIMHA ; Shaun CHAN ; Hlaing Hlaing WIN ; Chandramohan SIVANATHAN ; Bien Soo TAN
Annals of the Academy of Medicine, Singapore 2017;46(4):155-159