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Featured researches published by Jan Siewe.


Minimally Invasive Neurosurgery | 2009

Effectiveness, security and height restoration on fresh compression fractures--a comparative prospective study of vertebroplasty and kyphoplasty.

Marc Röllinghoff; Jan Siewe; Kourosh Zarghooni; Rolf Sobottke; Y. Alparslan; P. Eysel; K.-S. Delank

INTRODUCTION Painful fractures of the spine pose a serious clinical problem which gains in importance with the increasing ageing of our population. When conservative treatment of these fractures fails, with vertebroplasty and kyphoplasty we have two percutaneous minimally invasive stabilising procedures at our disposal. PATIENTS AND METHODS We performed a prospective study of 90 patients with fresh osteoporotic vertebral fractures who had been treated with vertebroplasty or kyphoplasty in our clinic between January 1, 2005, and December 31, 2007. Clinical analysis included Oswestry score and VAS index; the vertebral body height restoration (mean vertebral body height, kyphosis angle, anterior/posterior edge) was evaluated radiologically; furthermore, all occurring complications were recorded. The follow-up time was 1 year, 80 patients could be examined at follow-up; 8 patients had died of a tumour disease, lost to follow-up were 2.2%. RESULTS Both procedures succeeded in significantly (p<0.001) increasing quality of life (Oswestry score) and reducing pain (VAS). Following vertebroplasty there were two cases of cement leakage into the spinal canal with consecutive paraparesis which disappeared completely after the cement had been surgically removed. Altogether, 11 adjacent level fractures were observed, 4 in the vertebroplasty and 7 in the kyphoplasty group. CONCLUSION This study compares vertebroplasty and kyphoplasty with regard to their effectiveness, safety, and restoration of vertebral body height, and complications. There were no differences between the groups with regard to quality of life and pain improvement, but the rate of serious complications was higher after vertebroplasty. Mean vertebral body height restoration at 1 year follow-up was significantly higher (p<0.05) in the kyphoplasty group. It remains to be seen in future long-term studies whether or not restoration of vertebral body height has an effect on the clinical result.


International Journal of Sports Medicine | 2011

Injuries and Overuse Syndromes in Powerlifting

Jan Siewe; Marc Röllinghoff; Ulf J. Schlegel; P. Eysel; Joern William-Patrick Michael

Powerlifting is a discipline of competitive weightlifting. To date, no investigations have focused on pain encountered during routine training. The aim of the study was to identify such pain, assign it to particular exercises and assess the data regarding injuries as well as the influence of intrinsic and extrinsic factors. Data of 245 competitive and elite powerlifters was collected by questionnaire. Information regarding current workout routines and retrospective injury data was collected. Study subjects were selected from 97 incorporated powerlifting clubs. A percentage of 43.3% of powerlifters complained of problems during routine workouts. Injury rate was calculated as 0.3 injuries per lifter per year (1 000 h of training=1 injury). There was no evidence that intrinsic or extrinsic factors affected this rate. Most commonly injured body regions were the shoulder, lower back and the knee. The use of weight belts increased the injury rate of the lumbar spine. Rate of injury to the upper extremities was significantly increased based on age >40 years (shoulder/p=0.003, elbow/p=0.003, hand+wrist/p=0.024) and female gender (hand+wrist/p=0.045). The daily workout of a large proportion of powerlifters is affected by disorders which do not require an interruption of training. The injury rate is low compared to other sports.


International Orthopaedics | 2011

Pulsed lavage improves fixation strength of cemented tibial components

Ulf J. Schlegel; Jan Siewe; K.-S. Delank; P. Eysel; Klaus Püschel; Michael M. Morlock; Anne Uhlenbrock

Pulsatile lavage is purported to improve radiographic survival in cemented total knee arthroplasty (TKA). Similarly, a potential improvement of fixation strength of the tibial tray has been assumed based on the increased cement penetration. In this study, the influence of pulsed lavage on fixation strength of the tibial component and bone cement penetration was evaluated in six pairs of cadaveric specimens. Following surgical preparation, the tibial surface was irrigated using pulsatile lavage on one side of a pair, while on the other side syringe lavage was applied. All tibial components were implanted using the same cementing technique. Cement penetration and bone mineral density was assessed based on computed tomography data. Fixation strength of the tibial trays was determined by a pull-out test with a material testing machine. Median pull-out forces and cement penetration were significantly (p = 0.031) improved in the pulsed lavage group as compared to the syringe lavage group. Enhanced fixation strength is suggested as being a key to improved survival of the implant. Consequently, pulsatile lavage should be considered as a mandatory preparation step when cementing tibial components in TKA.


Minimally Invasive Neurosurgery | 2010

Clinical Outcomes and Quality of Life 1 Year after Open Microsurgical Decompression or Implantation of an Interspinous Stand-Alone Spacer

Rolf Sobottke; Marc Röllinghoff; Jan Siewe; Ulf J. Schlegel; Yagdiran A; Spangenberg M; Lesch R; Peer Eysel; Timmo Koy

BACKGROUND Interspinous stand-alone implants are inserted without open decompression to treat symptomatic lumbar spinal stenosis (LSS). The insertion procedure is technically simple, low-risk, and quick. However, the question remains whether the resulting clinical outcomes compare with those of microsurgical decompression, the gold standard. MATERIAL AND METHODS This prospective, comparative study included all patients (n=36) with neurogenic intermittent claudication (NIC) secondary to LSS with symptoms improving in forward flexion treated operatively with either interspinous stand-alone spacer insertion (Aperius (®); Medtronic, Tolochenaz, Switzerland) (group 1) or microsurgical bilateral operative decompression (group 2) between February 2007 and November 2008. Data (patient data, operative data, COMI, SF-36 PCS and MCS, ODI, and walking tolerance) were collected preoperatively as well as at 6 weeks, at 3, 6, and 9 months, and at one year follow-up (FU). All patients had complete FU over 1 year. RESULTS Compared to preoperative measurements, surgery led to improvements of all parameters in the entire collective as well as both individual groups. There were no statistically relevant differences between the 2 groups over the entire course of FU. However, improvements in the ODI and SF-36 MCS were not significant in group 1, in contrast to those of group 2. Also, although in group 1 the improvements in leg pain (VAS leg) were still significant (p<0.05) at 6 months, this was no longer the case at 1 year FU. In group 1 at 1 year FU an increase in leg pain was observed, while in group 2,  minimal improvements continued. Walking tolerance was significantly improved at all FU times compared to preoperatively, regardless of group (p<0.01). At no time there was a significant difference between the groups. In group 1, admission and operative times were shorter and blood loss decreased. The complication rate was 0% in group 1 and 20% in group 2, however reoperation was required by 27.3% of group 1 patients and 0% of group 2. CONCLUSION Implantation of an interspinous stand-alone spacer yields clinical success comparable to open decompression, at least within the first year of FU. The 1-year conversion rate of 27.3% is, however, decidedly too high.


Zeitschrift Fur Orthopadie Und Unfallchirurgie | 2013

Ist eine Höhenrekonstruktion mit vergleichsweise wenig Zement für die Radiofrequenz-Kyphoplastie über einen monopedikulären Zugang möglich?

M. Röllinghoff; A. Hagel; Jan Siewe; N. Gutteck; K.-S. Delank; A. Steinmetz; Kourosh Zarghooni

BACKGROUND Percutaneous cement augmentation systems have been proven to be an effective treatment for vertebral compression fractures in the last 10 years. A special form available since 2009 is the radiofrequency kyphoplasty (RF) in which the applied energy raises the viscosity of the cement. The aim of this study is to find out if a smaller cement amount in radiofrequency kyphoplasty can also restore vertebral body height in osteoporotic vertebral compression fractures. METHODS The treatment was minimally invasive using the StabiliT® vertebral augmentation system by DFine. In a retrospective study from 2011 to January 2012, 35 patients underwent RF kyphoplasty for 49 fresh osteoporotic vertebral compression fractures. From the clinical side the parameters, demographics and pain relief using a visual analogue scale (VAS: 0 to 100 mm) were collected. For the radiological outcome the vertebral body height (anterior, mean and posterior vertebral body height with kyphosis angle) after surgery and after three months was measured and compared to the cement volume. RESULTS All patients still had permanent pain on the fractured level after conservative treatment. The time from initial painful fracture to treatment was 3.0 weeks ± 1.3. Average visual analogue scale results decreased significantly from 71 ± 9.2 preoperatively to 35 ± 6.2 postoperatively (p < 0.001) and to 30 ± 5.7 (p < 0.001) after three months. With a mean cement volume in the thoracic spine of 2.9 ± 0.7 ml (1.8-4.1) and lumbar spine of 3.0 ± 0.7 ml (2.0-5.0) we had a significant vertebral body height restoration. Anterior and mean vertebral body heights significantly increased by an average of 2.3 and 3.1 mm, kyphosis angle significantly decreased with an average of 2.1° at three-month follow-up (p < 0.05). In two vertebrae (4.1 %) a minimal asymptomatic cement leakage occurred into the upper disc. In two patients (5.7 %) we had new fractures in the directly adjacent segment that were also successfully treated with radiofrequency kyphoplasty. CONCLUSION With a mean cement volume of 3.0 ml radiofrequency kyphoplasty achieves rapid and short-term improvements of clinical symptoms with a significant restoration of vertebral body height. There was no correlation between restoration of vertebral body height and pain relief. With a cement leakage of 4.1 % RF kyphoplasty is a safe and effective minimally invasive percutaneous cement augmentation procedure. Our data confirm the higher safety described in literature for kyphoplasty in contrast to vertebroplasty.


Orthopaedics & Traumatology-surgery & Research | 2015

Ultrasound-guided diagnosis of fractures of the distal forearm in children

C. Herren; R. Sobottke; M.J. Ringe; D. Visel; M. Graf; D. Müller; Jan Siewe

PURPOSE Distal radius and forearm fractures are injuries that are frequently seen in trauma surgery outpatient clinics. Usually, the wrist is X-rayed in 2 planes as standard diagnostic procedure. In contrast, we evaluate in our study the accuracy of ultrasonography (US) in diagnosing these fractures. METHODS This prospective study includes the patients who presented at two trauma surgery clinics with a presumptive diagnosis of distal radius or forearm fracture between January and December 2012. After a clinical examination, US imaging of the distal forearm was first carried out on 6 standardized planes followed by radiographs of the wrist made in two planes. The age limit was set at the end of 11 years. RESULTS In total, 201 patients between 4 and 11 years of age were recruited with an average age of 9.5 years at the time of the trauma. There were 104 (51.7%) fractures distributed as follows: 89 (85.9%) injuries of the distal radius, 9 (8.7%) injuries of the distal ulna, and 6 (5.8%) combined injuries (radius and ulna). Sixty-five greenstick fractures were detected. Surgery was necessary in 34 cases. Specificity and sensitivity of ultrasound diagnosis were 99.5%. CONCLUSION Ultrasound imaging is suitable to demonstrate fractures of the distal forearm. It is a highly sensitive procedure in detecting distal forearm fractures. In our opinion, a negative result in ultrasound may reduce the need for further radiographs in children with distal forearm lesions. But in any doubtful situation the need for conventional radiographs remains.


Deutsches Arzteblatt International | 2013

The Orthotic Treatment of Acute and Chronic Disease of the Cervical and Lumbar Spine

Kourosh Zarghooni; Frank Beyer; Jan Siewe; P. Eysel

BACKGROUND Orthoses are external aids that are often used to treat pain and diseases affecting the spine, such as lumbago, whiplash, and disc herniation. In this review, we assess the effectiveness and complications of orthotic treatment for typical spinal conditions and after spinal surgery. The orthotic treatment of fractures and postural abnormalities are beyond the scope of this article. METHOD This review is based on a selective search in the Medline database with consideration of controlled trials, systematic reviews, and the recommendations of the relevant medical societies. RESULTS Three relevant systematic reviews and four controlled trials were found. Very few controlled trials to date have studied the efficacy of orthotic treatment compared to other conservative treatments and surgery. No definitive evidence was found to support the use of orthoses after surgery, in lumbar radiculopathy, or after whiplash injuries of the cervical spine. In a single trial, short-term immobilization was an effective treatment of cervical radiculopathy. Orthoses are not recommended for nonspecific low back pain. The potential complications of cervical orthoses include pressure-related skin injuries and dysphagia. CONCLUSION No definitive evidence as yet supports the use of orthoses after spinal interventions or in painful conditions of the cervical or lumbar spine. They should, therefore, be used only after individual consideration of the indications in each case.


International Journal of Sports Medicine | 2014

Injuries and Overuse Syndromes in Competitive and Elite Bodybuilding

Jan Siewe; G. Marx; P. Knöll; P. Eysel; Kourosh Zarghooni; M. Graf; C. Herren; R. Sobottke; J. Michael

Competitive bodybuilding is a weightlifting sport similar to powerlifting, strongman competition and Olympic weightlifting, which aims to increase muscle mass, symmetry, and body definition. Although data regarding rates of injury, overuse syndromes and pain during routine training is available for these other disciplines, it is rare for competitive bodybuilding. The aim of this study was to investigate rates of injury, pain during workouts and/or overuse syndromes, as well as the influence of particular intrinsic and external factors. Data was collected using questionnaires from 71 competitive and elite bodybuilders. The information included training routines and prior injuries. Participants were recruited from bodybuilding clubs in Germany. 45.1% of athletes reported symptoms while training. The overall injury rate was computed to be 0.12 injuries per bodybuilder per year (0.24 injuries per 1 000 h of bodybuilding). Athletes over 40 exhibited higher rates of injury (p=0.029). Other investigated parameters showed no effects. Most injuries occurred in the shoulder, elbow, lumbar spine and knee regions. A large proportion of bodybuilders complained of pain not resulting in interruptions of training/competition. The injury rate is low compared to other weightlifting disciplines such as powerlifting, Olympic weightlifting or strongman competition. In comparison to team or contact sports the injury rate is minimal.


International Journal of Sports Medicine | 2014

Injuries in Competitive Boxing. A Prospective Study

Jan Siewe; Kourosh Zarghooni; R. Sobottke; P. Eysel; C. Herren; P. Knöll; U. Illgner; Joern William-Patrick Michael

Boxing remains a subject of controversy and is often classified as dangerous. But the discussion is based mostly on retrospective studies. This survey was conducted as a prospective study. From October 2012 to September 2013, 44 competitive boxers were asked to report their injuries once a month. The questionnaire collected general information (training, competition) and recorded the number of bouts fought, injuries and resulting lost days. A total of 192 injuries were recorded, 133 of which resulted in interruption of training or competition. Each boxer sustained 3 injuries per year on average. The injury rate was 12.8 injuries per 1 000 h of training. Boxers fighting more than 3 bouts per year sustain more injuries (p=0.0075). The injury rate does is not a function of age (age≤19 vs. > 19a, p=0.53). Injuries to the head and the upper limbs occur most frequently. The most common injuries are soft tissue lacerations and contusions. Head injuries with neurological symptoms rarely occur (4.2%). Boxing has a high injury rate that is comparable with other contact sports, but most injuries are minor. Injury frequency is not a function of whether the boxer competes in the junior or adult category. Athletes fighting many bouts per year have a greater risk of injury.


Journal of Trauma-injury Infection and Critical Care | 2015

Spinal cord injury without radiologic abnormality in children: A systematic review and meta-analysis

Christoph Kolja Boese; Johannes Oppermann; Jan Siewe; P. Eysel; Max Joseph Scheyerer; Philipp Lechler

BACKGROUND Spinal cord injury in children is associated with severe morbidity and immense socioeconomic burden. In spinal cord injury without radiologic abnormalities (SCIWORA), magnetic resonance imaging (MRI) can detect intramedullary or extramedullary pathologies or show absence of neuroimaging abnormalities. However, the prognostic and therapeutic consequences of specific MRI patterns are unclear. A comprehensive systematic literature search was performed to examine patient characteristics and imaging patterns of pediatric SCIWORA and to evaluate the prognostic value of a MRI-based classification system. METHODS MEDLINE, Cochrane Central Register of Controlled Trials, and Google Scholar were searched for studies on SCIWORA in children. Inclusion criteria were (1) traumatic spinal cord injury with acute neurologic deficit, (2) absence of fractures and/or dislocations of the spine, and (3) an immature skeleton or age of less than 18 years. MRI patterns and clinical course were correlated. RESULTS Forty articles reporting 114 patients were identified. At admission, neurologic deficit assessed by the American Spinal Injury Association impairment scale was A in 28%, B in 17%, C in 31%, and D in 25%. At final follow-up, these were 19%, 6%, 10%, and 16%, respectively. In 43%, no MRI abnormalities (Type I) were detected, and 57% exhibited abnormal scan results (Type II): 6% revealed extraneural (Type IIa), 38% intraneural (Type IIb), and 13% combined abnormalities (Type IIc). At admission and follow-up, American Spinal Injury Association impairment scale differed significantly between the imaging types. CONCLUSION This systematic review emphasizes the prognostic value of spinal MRI for children with SCIWORA. It highlights the role of the MRI classification system in improving the comparability and interpretability. LEVEL OF EVIDENCE Systematic review, level IV.

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P. Eysel

University of Cologne

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