Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Kan Min is active.

Publication


Featured researches published by Kan Min.


Spine | 2006

Nonoperative treatment for adolescent idiopathic scoliosis : A 10- to 60-year follow-up with special reference to health-related quality of life

Mathias Haefeli; Achim Elfering; Reinhold Kilian; Kan Min; Norbert Boos

Study Design. Retrospective study on patients 10 to 60 years of age after nonoperative treatment for adolescent idiopathic scoliosis (AIS). Objectives. To investigate long-term outcome with regard to pain, disability, psychological disturbance, and health-related quality of life (HRQOL) in nonoperatively treated patients with AIS. Summary of Background Data. Only little is known on the long-term quality of life and disability in patients nonoperatively treated for AIS. A detailed knowledge of the nonoperative treatment results is important when advising patients for surgery. Methods. A total of 135 nonoperatively treated AIS patients with a minimum follow-up of 10 years were included in this investigation, 121 of whom responded to a questionnaire containing questions on pain, disability (Oswestry Disability Index [ODI], Hannover Functional Ability Questionnaire [HFAQ], psychological general well-being [PGWB], and health-related quality of life [WHOQOLBREF]). Eighty-one patients participated in a clinical/radiologic follow-up examination. Nonoperative treatment consisted of bracing (n = 60), physiotherapy (n = 59), and electrical stimulation (n = 2). The overall follow-up rate was 89.6%. The mean age at follow-up was 38.0 years (range, 20–73 years.). Results. In general, patients achieved a satisfactory outcome 10 to 60 years (mean, 23 years) after nonoperative treatment with regard to pain, disability, and HRQOL. The average curve at first diagnosis measured 29.5° (range, 15°–59°) for the thoracic spine, 21.3° (range, 15°–28°) for the thoracolumbar spine, and 26.8° (10°–44°) for the lumbar spine. Thirteen patients showed a substantial change in curve size (±10°) between first diagnosis and end of growth: 11 curves progressed more than 10° showing an average increase of 19.0° (range, 12°–30°) and 2 patients presented with less severe curves at follow-up (−10° and −13°). After end of growth, 7 patients showed a substantial average increase of 16.3° (range, 10°–31°). Five of eight patients with thoracic curves greater than 80° had restrictive pulmonary disease. Patients with curves greater than 45° reported significantly higher pain levels than those with smaller curves. Patients only showed a minimal absolute disability (Oswestry and HFAQ), and no significant correlation was found between curve size and curve type, respectively. Compared with a healthy control group that was matched for age and gender, no significant differences were found in terms of HRQOL as assessed by the WHOQOLBREF questionnaire. No significant differences in pain, disability, or HRQOL were found between patients with and without brace treatment. Conclusions. Although pain, disability, HRQOL, and psychological general well-being are quite satisfactory on an absolute level, curve size was found to be a significant predictor for pain in a long-term follow-up.


European Spine Journal | 2005

Primary thoracoplasty and pedicle screw instrumentation in thoracic idiopathic scoliosis

Kan Min; Beat Waelchli; Frederik Hahn

Thoracoplasty in combination with spine fusion is an established method to address the rib cage deformity in idiopathic scoliosis. Most reports about thoracoplasty and scoliosis correction focused on Harrington or CD instrumentation. We report a retrospective analysis of 21 consecutive patients, who were treated with pedicle screw instrumentation for idiopathic thoracic scoliosis and concomitant thoracoplasty. Minimal follow up was 24 (24–75) months. Indication for thoracoplasty was clinical rib prominence of more than 15°. In average there was a 44% correction of clinical rib hump, from 18 (15–25°) to 10° (0–18°) (p<0.0001) and a 40% correction of radiological rib hump, from 15 (5–20°) to 9°(2–15°) (p<0.0001). The preoperative pulmonary function, accessed by forced vital capacity (FVC) and one-second forced expiratory volume (FEV1), remained unchanged at the last follow up. The distal end of fusion was the end vertebra of the curve in 83.3% and the end vertebra plus one in 16.7% of the patients. There was a 68% correction of instrumented primary thoracic curves, from 60 (45–85°) to 19°(5–36°) (p<0.0001), and a 45% correction of non-instrumented secondary lumbar curves, from 40 (28–60°) to 22°(8–38°) (p<0.0001). Apical vertebral rotation (AVR) of the thoracic curves improved 54%, from 24 (10–35°) to 11° (5–20°) (p<0.0001). The tilt of lowest instrumented vertebra (LIV) improved 68%, from 28 (20–42°) to 9°(3–20°) (p<0.0001). There was no significant change in sagittal profile of the spine. Analysis with SRS-24 questionnaire showed that the majority of the patients were very satisfied with the outcome. A matched control group (n=21) operated by the same surgeon with the same operation technique but without concomitant thoracoplasty was chosen for comparison. The scoliosis correction in the two groups was comparable. The patients without thoracoplasty had 37% spontaneous improvement of the clinical rib hump.


BMC Musculoskeletal Disorders | 2010

LumbSten: The lumbar spinal stenosis outcome study

Johann Steurer; Alexander Nydegger; Ulrike Held; Florian Brunner; Jürg Hodler; François Porchet; Kan Min; Anne F. Mannion; Beat Michel

BackgroundLumbar spinal stenosis is the most frequent reason for spinal surgery in elderly people. For patients with moderate or severe symptoms different conservative and surgical treatment modalities are recommended, but knowledge about the effectiveness, in particular of the conservative treatments, is scarce. There is some evidence that surgery improves outcome in about two thirds of the patients. The aims of this study are to derive and validate a prognostic prediction aid to estimate the probability of clinically relevant improvement after surgery and to gain more knowledge about the future course of patients treated by conservative treatment modalities.Methods/DesignThis is a prospective, multi-centre cohort study within four hospitals of Zurich, Switzerland. We will enroll patients with neurogenic claudication and lumbar spinal stenosis verified by Computer Tomography or Magnetic Resonance Imaging. Participating in the study will have no influence on treatment modality. Clinical data, including relevant prognostic data, will be collected at baseline and the Swiss Spinal Stenosis Questionnaire will be used to quantify severity of symptoms, physical function characteristics, and patients satisfaction after treatment (primary outcome). Data on outcome will be collected 6 weeks, and 6, 12, 24 and 36 months after inclusion in the study. Applying multivariable statistical methods, a prediction rule to estimate the course after surgery will be derived.DiscussionThe ultimate goal of the study is to facilitate optimal, knowledge based and individualized treatment recommendations for patients with symptomatic lumbar spinal stenosis.


BJA: British Journal of Anaesthesia | 2015

Higher fibrinogen concentrations for reduction of transfusion requirements during major paediatric surgery: A prospective randomised controlled trial

Thorsten Haas; Nelly Spielmann; T. Restin; Burkhardt Seifert; G. Henze; J. Obwegeser; Kan Min; D. Jeszenszky; Markus Weiss; M. Schmugge

BACKGROUND Hypofibrinogenaemia is one of the main reasons for development of perioperative coagulopathy during major paediatric surgery. The aim of this study was to assess whether prophylactic maintenance of higher fibrinogen concentrations through administration of fibrinogen concentrate would decrease the volume of transfused red blood cell (RBCs). METHODS In this prospective, randomised, clinical trial, patients aged 6 months to 17 yr undergoing craniosynostosis and scoliosis surgery received fibrinogen concentrate (30 mg kg(-1)) at two predefined intraoperative fibrinogen concentrations [ROTEM(®) FIBTEM maximum clot firmness (MCF) of <8 mm (conventional) or <13 mm (early substitution)]. Total volume of transfused RBCs was recorded over 24 h after start of surgery. RESULTS Thirty children who underwent craniosynostosis surgery and 19 children who underwent scoliosis surgery were treated per protocol. During craniosynostosis surgery, children in the early substitution group received significantly less RBCs (median, 28 ml kg(-1); IQR, 21 to 50 ml kg(-1)) compared with the conventional fibrinogen trigger of <8 mm (median, 56 ml kg(-1); IQR, 28 to 62 ml kg(-1)) (P=0.03). Calculated blood loss as per cent of estimated total blood volume decreased from a median of 160% (IQR, 110-190%) to a median of 90% (IQR, 78-110%) (P=0.017). No significant changes were observed in the scoliosis surgery population. No bleeding events requiring surgical intervention, postoperative transfusions of RBCs, or treatment-related adverse events were observed. CONCLUSIONS Intraoperative administration of fibrinogen concentrate using a FIBTEM MCF trigger level of <13 mm can be successfully used to significantly decrease bleeding, and transfusion requirements in the setting of craniosynostosis surgery, but not scoliosis. CLINICAL TRIAL REGISTRY NUMBER ClinicalTrials.gov NCT01487837.


Journal of Pediatric Orthopaedics | 2011

Changes in health-related quality of life after spinal fusion and scoliosis correction in patients with cerebral palsy.

Christina Bohtz; Andreas Meyer-Heim; Kan Min

Background The literature is scarce on the impact of spinal fusion for scoliosis in patients with cerebral palsy (CP) regarding the health-related quality of life (HRQL). The purpose of this study was to evaluate the outcome of surgical scoliosis correction measured by the subjective change in the HRQL and the objective radiologic changes. Factors that could influence the subjective outcome were examined to investigate their correlation to the results of HRQL. Methods A retrospective review of 50 consecutive patients with CP, who had spinal fusion for scoliosis with minimal 2-year follow-up was carried out. Radiographic data were obtained from preoperative, postoperative, and last follow-up examinations. The assessment of the HRQL was done through a modified version of the “Caregiver Priorities and Child Health Index of Life with Disabilities” questionnaire, assessed by the caregivers of the patients. Results There was a significant improvement (P=0.001) of HRQL after the operation. The satisfaction rate of the patients with the outcome of the operation was 91.7%. There was an average of 64.3% scoliosis correction, 57.7% pelvic tilt correction, 53% improvement of apical vertebral rotation, and 67.2% improvement of apical vertebral translation. At the last follow-up, the average scoliosis angle was 32.0 degrees and pelvic tilt was 8.8 degrees. Weak but not significant correlation between the amount of scoliosis correction and the subjective change in the HRQL could be established (R2=0.321, P=0.078). No correlation between the occurrence of complications and changes in the HRQL (P=0.122) or the satisfaction rate with the outcome of the operation (P=0.764) was found. Extension of spinal fusion to sacropelvis had no influence on the occurrence of complications (P=0.42) or on the changes in HRQL (P=0.71). Conclusions Life quality improved after surgical scoliosis correction in patients with CP. There is a high satisfaction rate of patients and their caregivers. Subjective changes in HRQL after the operation do not correlate with objective radiographic changes brought about by the operation, which indicates that the present operation indications and achieved correction are adequate to achieve an improvement of the subjective HRQL in this patient group. Level of Evidence Therapeutic level IV, retrospective study.


Neurology | 2013

Improved diagnosis of spinal cord disorders with contact heat evoked potentials

Anett Ulrich; Jenny Haefeli; Julia Blum; Kan Min; Armin Curt

Objective: To evaluate the sensitivity of contact heat evoked potentials (CHEPs) compared with dermatomal somatosensory evoked potentials (dSSEPs) and clinical sensory testing in myelopathic spinal cord disorders (SCDs). Methods: In a prospective cohort study, light-touch (LT) and pinprick (PP) testing was complemented by dermatomal CHEPs and dSSEPs in patients with a confirmed SCD as defined by MRI. Patients with different etiologies (i.e., traumatic and nontraumatic) and varying degrees of spinal cord damage (i.e., completeness) were included. SCD was distinguished into 3 categories according to MRI pattern and neurologic examination: a) complete, b) incomplete-diffuse, and c) central or anterior cord damage. Results: Seventy-five patients were included (complete n = 7, incomplete-diffuse n = 33, central/anterior n = 35). In total, 319 dermatomes were tested with combined CHEPs and dSSEPs. CHEPs, dSSEPs, and clinical sensory testing were comparably sensitive to detect the myelopathy in complete (CHEPs 100%, dSSEPs 91%, PP and LT 82%) and incomplete-diffuse (CHEPs 92%, dSSEPs and PP 86%, LT 81%, p > 0.05 for all comparisons) cord damage. In central/anterior cord damage, CHEPs showed a significantly higher sensitivity than dSSEPs (89% compared with 24%, p < 0.001) and clinical sensory testing (PP 62%, LT 57%, p < 0.05). A subclinical sensory impairment was detected more frequently by CHEPs than dSSEPs (60% compared with 29%, p = 0.001). Conclusions: Assessment of spinothalamic pathways with CHEPs is reliable and revealed the highest sensitivity in all SCDs. Specifically in incomplete lesions that spare dorsal pathways, CHEPs are sensitive to complement the clinical diagnosis.


European Spine Journal | 2002

Vertebral body compression fracture after removal of pedicle screws: a report of two cases.

Beat Waelchli; Kan Min; Philippe Cathrein; Norbert Boos

Abstract. While the risks of pedicle screw insertion are well established, there is a paucity of reports on complications associated with implant removal. We report two cases of acute osteoporotic vertebral compression fractures of the instrumented vertebral body adjacent to the fractured vertebra due to removal of pedicle screws in two female patients previously treated for vertebral lumbar burst fractures. Both patients had experienced only mild occasional pain at the thoracolumbar junction prior to the removal of the implants. In the formerly almost asymptomatic individuals, the acute osteoporotic fractures led to persistent severe back pain despite prolonged intensive treatment. Patients must be thoroughly informed of the rare but potential risks of spinal implant removal, particularly in cases of osteoporosis. We therefore do not recommend removal of spinal implants unless there are clear clinical indications for implant removal.


European Spine Journal | 2012

Sacral dome resection and single-stage posterior reduction in the treatment of high-grade high dysplastic spondylolisthesis in adolescents and young adults

Kan Min; Thomas Liebscher; Dominique A. Rothenfluh

ObjectiveThe description of the operation technique and retrospective review of 15 consecutive patients who were treated by posterior sacral dome resection and single-stage reduction with pedicle screw fixation for high-grade, high-dysplastic spondylolisthesis.Materials and methodsAll the patients had high-grade, high-dysplatic spondylolisthesis L5 and were treated by posterior sacral dome resection and posterior single-stage reduction from L4–S1. The average age at the time of surgery was 17.3 (11–28) years. The average follow-up time is 5.5 (2–11.6) years. Clinical and radiologica data were retrospectively reviewed.ResultsSpondylolisthesis was reduced from average 99% preoperative to 29% at the last follow-up. L5 incidence improved from 74° to 56°, the lumbosacral angle improved from 15° kyphosis to 6° lordosis, lumbar lordosis decreased from 69° to 53° from preoperative to the last follow-up. While pelvic incidence of 77° remained unchanged, sacral slope decreased from 51° to 46° and pelvic tilt increased from 25° to 30°. Clinical outcome was subjectively rated to be much better than before surgery by 14 out of 15 patients. Four out of 15 patients had temporary sensory impairment of the L5 nerve root which resolved completely within 12 weeks. There were no permanent neurological complications or no pseudarthrosis.ConclusionThe sacral dome resection is a shortening osteotomy of the lumbosacral spine which allows a single-stage reduction of L5 without lengthening of lumbosacral region in high-grade spondylolisthesis, which helps to avoid neurological complications. This is a safe surgical technique resulting in a good multidimensional deformity correction and restoration of spino-pelvic alignment towards normal values with a satisfactory clinical outcome.


Journal of Spinal Disorders & Techniques | 2007

Lumbar Spinal Osteotomy for Kyphosis in Ankylosing Spondylitis: The Significance of the Whole Body Kyphosis Angle

Kan Min; Frederik Hahn; Massimo Leonardi

Retrospective analysis of 11 consecutive patients with ankylosing spondylitis who underwent lumbar spinal osteotomy for severe kyphosis, with a mean follow up of 4 (2 to 8.5) years. The chin brow vertical angle, thigh flexion angle, and the whole body kyphosis angle (WBKA) were measured on the clinical photographs of the patient in standing. The lumbar lordosis, thoracic kyphosis, total kyphosis, sacral slope, and sagittal balance were measured on the standing radiographs. A closing wedge osteotomy at L3 was done in all patients. Intraoperative neuromonitor with sensory evoked potentials and motor evoked potentials was used routinely. Stable fixation of spine allowed early walking. There were no permanent neurologic complications. The average preoperative WBKA was 41 degrees (20 to 70 degrees). The average correction of lumbar lordosis was 40 degrees, from 21.4 degrees (−10 to 65 degrees) to 61.4 degrees (35 to 85 degrees). The thigh flexion angle improved from 9.7 degrees (4 to 20 degrees) to 0.4 degrees (−4 to 5 degrees), the sacral slope from 11.8 degrees (−5 to 35 degrees) to 31.8 degrees (20 to 45 degrees), and the chin brow vertical angle from 28.2 degrees (10 to 45 degrees) to 2.4 degrees (−5 to 18 degrees). Loss of correction of 5 and 10 degrees was seen in 2 patients. The ability to stand upright and look straight was restored in all patients. The WBKA correlated closely with the amount of lordosis correction in lumbar spine. The intraobserver and interobserver reproducibility of the WBKA was verified by statistical analysis. In our opinion the measurement of the WBKA on the preoperative photograph is helpful in planning the lumbar osteotomy.


Clinical Neurophysiology | 2002

Transcranial electrical stimulation: significance of fast versus slow charge delivery for intra-operative monitoring

Oliver Hausmann; Kan Min; Norbert Boos; Yvan A Ruetsch; Thomas Erni; Armin Curt

OBJECTIVES Motor-evoked potentials (MEP) for intra-operative monitoring due to fast charge (fc: 1.0 Coulomb/s) and slow charge (sc: 0.1Coulomb/s) delivery for multipulse transcranial electrical stimulation (TES) were compared. METHODS MEPs due to fc (n=162) and sc stimulation (n=182) were performed in parallel in a prospective study. The fc stimulation technique is characterized by an increased steepness of charge delivery with consequent reduction of stimulus duration of 50 micros compared to 500 micros in sc stimulation. Stimulation charges (C=Coulomb) and MEP parameters during spine surgery were analyzed. RESULTS MEPs were successfully recorded in 15/18 patients under total intravenous anesthesia. The mean charge to induce intra-operative MEPs (stimulation threshold) was significantly less in fc (0.195 mC) as compared to sc stimulation (0.298 mC). With both stimulation techniques, in all patients without impairment of motor function, MEPs could be recorded and no technique was superior with respect to successful stimulation. The mean MEP latencies, amplitudes and the extent of intra-individual variation of MEP parameters during surgery (shift of latency less than 10%, variability of amplitude less than 50%) were not different with both stimulation techniques. CONCLUSIONS TES with either fc or sc stimulation can be used reliably for intraoperative monitoring. Fc and sc stimulation are comparable with respect to feasibility, intra-individual variability and mean parameters of MEP responses. However, fc stimulation provides a higher stimulation efficiency and requires about 35% less total charge for MEP monitoring.

Collaboration


Dive into the Kan Min's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge