Lakemeier, Stefan

[["dc.bibliographiccitation.firstpage","473"],["dc.bibliographiccitation.issue","6"],["dc.bibliographiccitation.journal","Biomedical Engineering / Biomedizinische Technik"],["dc.bibliographiccitation.lastpage","480"],["dc.bibliographiccitation.volume","57"],["dc.contributor.author","Foelsch, Christian"],["dc.contributor.author","Goost, Hans"],["dc.contributor.author","Figiel, Jens"],["dc.contributor.author","Paletta, Juergen R. J."],["dc.contributor.author","Schultz, Wolfgang"],["dc.contributor.author","Lakemeier, Stefan"],["dc.date.accessioned","2018-11-07T09:02:38Z"],["dc.date.available","2018-11-07T09:02:38Z"],["dc.date.issued","2012"],["dc.description.abstract","Background: Cement augmentation of pedicle screws increases fixation strength in an osteoporotic spine. This study was designed to determine the cement distribution and the correlation between the pull-out strength of the augmented screw and the cement volume within polyurethane (PU) foam. Methods: Twenty-eight cannulated pedicle screws (6 x 45 mm) (Peter Brehm, Erlangen, Germany) with four holes at the distal end of the screw were augmented with the acrylic Stabilit ER Bone Cement Vertebral Augmentation System (DFine Inc., San Jose, CA, USA) and implanted into open-cell rigid PU foam (Pacific Research Laboratories, Vashon Island, WA, USA) with a density of 0.12 g/cm(3), resembling severe osteoporosis. Volumetric measurement of the cement with consideration of the distribution around the screws was done with multislice computed tomography scan (Somatom Definition, Siemens, Erlangen, Germany). Pull-out strength was tested with a servohydraulic system (MTS System Corporation, Eden Prairie, MN, USA), and nonaugmented screws served as control. Pearson ' s correlation coefficient with significance level a = 0.05 and one-way analysis of variance test were used. Results: We found a high (r = 0.88) and significant (p < 0.01) correlation between the cement volume and the pull-out strength, which increased by more than 5-fold with a volume of 3 ml. The correlation appeared linear at least up to 4 ml cement volume and failure always occurred at the cement-bone interface. The cement distribution was symmetric and circular around the most proximal hole, with a distance of 14 mm from the tip, and nearly 90% of the cement was found 6 mm distal and cranial to it. The 95% confidence interval for the relative amount of cement was 37% -41% within 2 mm of the most proximal hole. Conclusion: Compared with the control, a cement volume between 2.0 and 3.0 ml increased the pull-out strength significantly and is relevant for clinical purposes, whereas a volume of 0.5 ml did not. A cement volume beyond 3.0 ml should further increase the pull-out strength because the correlation was linear at least up to 4.0 ml, but the possibility of in vivo cement leakage with increasing volume has to be considered. Pressure-controlled cement application might be a tool to avoid this complication. The cement almost completely penetrated the most proximal perforation."],["dc.identifier.doi","10.1515/bmt-2012-0012"],["dc.identifier.isi","000312707900007"],["dc.identifier.pmid","23152399"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/10598"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/24730"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Walter De Gruyter & Co"],["dc.relation.issn","0013-5585"],["dc.rights","Goescholar"],["dc.rights.uri","https://goescholar.uni-goettingen.de/licenses"],["dc.title","Correlation of pull-out strength of cement-augmented pedicle screws with CT-volumetric measurement of cement"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","292"],["dc.bibliographiccitation.issue","1"],["dc.bibliographiccitation.journal","Journal of Medical Case Reports"],["dc.bibliographiccitation.volume","9"],["dc.contributor.author","Hammad, Ahmed"],["dc.contributor.author","Leute, Philip J F"],["dc.contributor.author","Hoffmann, Isabel"],["dc.contributor.author","Hoppe, Sebastian"],["dc.contributor.author","Lakemeier, Stefan"],["dc.contributor.author","Klinger, Hans-Michael"],["dc.date.accessioned","2019-07-09T11:42:01Z"],["dc.date.available","2019-07-09T11:42:01Z"],["dc.date.issued","2015"],["dc.description.abstract","Abstract Background Brodie’s abscess is an uncommon form of subacute osteomyelitis where the main presenting symptom is mild to moderate pain of insidious onset for several months’ duration. We report a case of a patient presenting with acute leg pain resembling that of a deep vein thrombosis, and a beginning leg compartment syndrome following a suspected ruptured Baker’s cyst. Our case is unusual because of the acute presentation of the Brodie’s abscess with acute leg pain and acute swelling without any preceding trauma; to the best of our knowledge, this presentation has not been reported before. Case presentation A 17-year-old white boy presented to our out-patient clinic with a 6-month history of pain in his left knee joint of insidious onset. There was no history of trauma to the extremity. After performing physical and radiological (X-ray) examinations, we initially diagnosed medial meniscus damage. One week later he presented to our emergency department with acute sudden increase in the pain and swelling of his left knee, and pain and swelling of his left leg, without any trauma. Deep vein thrombosis and beginning leg compartment syndrome from ruptured Baker’s cyst were initially diagnosed. Magnetic resonance imaging was performed and Brodie’s abscess was the most probable diagnosis. We performed open surgical debridement and curettage with drainage of the abscess and administered postoperative antibiotics. He presented to our out-patient clinic 3 months postoperatively, where he was pain-free with no residual local tenderness. Conclusions In cases of sudden acute increase in joint or extremity pain or swelling that has been insidiously present for months, Brodie’s abscess should be considered as one of the differential diagnoses, as it may present acutely in cases with accompanying fasciitis and myositis and be clinically mistaken for deep vein thrombosis or limb compartment. Magnetic resonance imaging remains the gold standard imaging study, and surgical treatment followed by postoperative antibiotics remains the standard treatment."],["dc.identifier.doi","10.1186/s13256-015-0770-x"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/12658"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/58565"],["dc.language.iso","en"],["dc.notes.intern","Merged from goescholar"],["dc.rights","Goescholar"],["dc.rights.uri","https://goescholar.uni-goettingen.de/licenses"],["dc.title","Acute leg pain with suspected beginning leg compartment syndrome and deep vein thrombosis as differential diagnoses in an unusual presentation of Brodie’s abscess: a case report"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","111"],["dc.bibliographiccitation.issue","2"],["dc.bibliographiccitation.journal","Journal of orthopaedics and traumatology : official journal of the Italian Society of Orthopaedics and Traumatology"],["dc.bibliographiccitation.lastpage","120"],["dc.bibliographiccitation.volume","18"],["dc.contributor.author","Leute, Philip J. F."],["dc.contributor.author","Hoffmann, Isabel"],["dc.contributor.author","Hammad, Ahmed"],["dc.contributor.author","Lakemeier, Stefan"],["dc.contributor.author","Klinger, Hans-Michael"],["dc.contributor.author","Baums, Mike H."],["dc.date.accessioned","2019-02-14T16:50:32Z"],["dc.date.available","2019-02-14T16:50:32Z"],["dc.date.issued","2017"],["dc.description.abstract","Aseptic loosening after total hip arthroplasty is likely related to nicotine ingestion. However, aseptic loosening as a direct consequence of smoking habits has not been described with regard to proximal mega-prosthetic femoral replacement. The aim of the present study was to evaluate the association between nicotine consumption and aseptic loosening rates after proximal mega-prosthetic femoral replacement."],["dc.identifier.doi","10.1007/s10195-016-0426-7"],["dc.identifier.pmid","27535061"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/14192"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/57566"],["dc.language.iso","en"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","final"],["dc.relation.eissn","1590-9999"],["dc.rights","CC BY 4.0"],["dc.rights.uri","https://creativecommons.org/licenses/by/4.0"],["dc.title","Nicotine consumption may lead to aseptic loosening in proximal mega-prosthetic femoral replacement"],["dc.type","journal_article"],["dc.type.internalPublication","unknown"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","359"],["dc.bibliographiccitation.issue","2"],["dc.bibliographiccitation.journal","Acta Neurochirurgica"],["dc.bibliographiccitation.lastpage","365"],["dc.bibliographiccitation.volume","154"],["dc.contributor.author","Lakemeier, Stefan"],["dc.contributor.author","Schmid, Raphael"],["dc.contributor.author","Foltz, Lisa"],["dc.contributor.author","Rohlfs, Jochen"],["dc.contributor.author","Fuchs-Winkelmann, Susanne"],["dc.contributor.author","Efe, Turgay"],["dc.contributor.author","Foelsch, Christian"],["dc.contributor.author","Paletta, Jürgen R. J."],["dc.date.accessioned","2019-07-09T11:54:37Z"],["dc.date.available","2019-07-09T11:54:37Z"],["dc.date.issued","2011"],["dc.description.abstract","Background The most common spinal disorder in the elderly is lumbar spinal stenosis (LSS), which results in part from ligamentum flavum (LF) hypertrophy. Although prior histologic and immunochemical studies have been performed in this area, the pathophysiology of loss of elasticity and hypertrophy is not completely understood. The purpose of this immunohistological study is to elucidate the role of CD44 and its splice variants CD44v5 and CD44v6 in the hypertrophied LF obtained from patients with lumbar spinal stenosis (LSS). Materials and methods LF samples of 38 patients with LSS were harvested during spinal decompression. Twelve LF samples obtained from patients with disc herniation and no visible degeneration on preoperative MRI were obtained as controls. Samples were dehydrated and embedded in paraffin. For immunohistochemical determination, slices were stained with antibodies against CD44, Cd44v4, and CD44v6 stained with DAB. LF hypertrophy and cross-sectional area (CSA) were measured with T1-weighted MRI. Results CD44 and CD44v5 expression were significantly increased in the hypertrophy group (p<0.05). CD44v6 expression was not significantly increased. The number of elastic fibers was significantly higher in the hypertrophy group. In the hypertrophy group, LF thickness was significantly increased while CSA was significantly decreased. There was a statistical correlation between LF thickness, CSA, CD44, and CD44v5 expression in the hypertrophy group (p<0.05). Conclusions LF hypertrophy is accompanied by increased CD44 and CD44v5 expression. CD44v6 expression is not enhanced in LF hypertrophy."],["dc.format.extent","7"],["dc.identifier.doi","10.1007/s00701-011-1206-z"],["dc.identifier.fs","593532"],["dc.identifier.pmid","22052472"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/9467"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/60696"],["dc.language.iso","en"],["dc.notes.intern","Merged from goescholar"],["dc.relation.issn","0942-0940"],["dc.rights","Goescholar"],["dc.rights.uri","https://goescholar.uni-goettingen.de/licenses"],["dc.title","Increased expression of CD44 in hypertrophied ligamentum flavum and relevance of splice variants CD44v5 and CD44v6"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","22"],["dc.bibliographiccitation.journal","Journal of medical case reports"],["dc.bibliographiccitation.volume","9"],["dc.contributor.author","Leute, Philip Johannes Felix"],["dc.contributor.author","Hammad, Ahmed"],["dc.contributor.author","Hoffmann, Isabel"],["dc.contributor.author","Hoppe, Sebastian"],["dc.contributor.author","Klinger, Hans-Michael"],["dc.contributor.author","Lakemeier, Stefan"],["dc.date.accessioned","2019-07-09T11:42:26Z"],["dc.date.available","2019-07-09T11:42:26Z"],["dc.date.issued","2015"],["dc.description.abstract","INTRODUCTION: Transforaminal lumbar interbody fusion is a popular procedure used to achieve spondylodesis in patients with degenerative lumbar spinal diseases. We present a rare case of a patient with a set screw fracture with cage dislocation after an open transforaminal lumbar interbody fusion procedure. To the best of our knowledge, this case is the first of its kind to be reported. CASE PRESENTATION: A 44-year-old Caucasian woman attended a follow-up appointment at our hospital 3 months after treatment for second-degree lumbar spondylolisthesis (L4/L5) and osteochondrosis (L5/S1) with transforaminal lumbar interbody fusion and dorsal spondylodesis. She complained of severe leg pain on the left side. Her physical examination revealed a normal neurological status, except for paresthesia of the entire left lower limb and at the ball of the left foot. Radiological imaging showed breaking of the set screws with cage dislocation. Surgical revision was then performed with exchange of the whole dorsal instrumentation and the dislocated cage. Six weeks post-operatively, the patient was seen again at our clinic without neurological complaints, except for decreased sensitivity on the dorsum of her left foot. The wound healing and radiological follow-up were uneventful. CONCLUSIONS: Hardware-related complications are rarely seen in patients with open transforaminal lumbar interbody fusion, but must be kept in mind and can potentially cause severe neurological deficits."],["dc.format.extent","6"],["dc.identifier.doi","10.1186/1752-1947-9-22"],["dc.identifier.pmid","25609204"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/13451"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/58669"],["dc.language.iso","en"],["dc.notes.intern","Merged from goescholar"],["dc.relation.issn","1752-1947"],["dc.rights","CC BY 4.0"],["dc.rights.uri","https://creativecommons.org/licenses/by/4.0"],["dc.subject.mesh","Adult"],["dc.subject.mesh","Bone Screws"],["dc.subject.mesh","Female"],["dc.subject.mesh","Foreign-Body Migration"],["dc.subject.mesh","Humans"],["dc.subject.mesh","Lumbar Vertebrae"],["dc.subject.mesh","Reoperation"],["dc.subject.mesh","Spinal Fusion"],["dc.subject.mesh","Spondylolisthesis"],["dc.subject.mesh","Treatment Outcome"],["dc.title","Set screw fracture with cage dislocation after two-level transforaminal lumbar interbody fusion (TLIF): a case report."],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]