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Dive into the research topics where Ralf Gahr is active.

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Featured researches published by Ralf Gahr.


Spine | 2007

The influence of fracture mechanism and morphology on the reliability and validity of two novel thoracolumbar injury classification systems.

Peter G. Whang; Alexander R. Vaccaro; Kornelius A. Poelstra; Alpesh A. Patel; D. Greg Anderson; Todd J. Albert; Alan S. Hilibrand; James S. Harrop; Ashwini Sharan; John K. Ratliff; R. John Hurlbert; Paul Anderson; Bizhan Aarabi; Lali Sekhon; Ralf Gahr; John A. Carrino

Study Design. The Thoracolumbar Injury Severity Score (TLISS) and the Thoracolumbar Injury Classification and Severity Score (TLICS) were prospectively evaluated. Objectives. To compare the reliability and validity of the TLISS and TLICS schemes to determine the importance of injury mechanism and morphology to the identification and treatment of thoracolumbar fractures. Summary of Background Data. Two novel algorithms have been developed for the categorization and management of thoracolumbar injuries: the TLISS system emphasizing injury mechanism and the TLICS scheme involving injury morphology. Methods. The clinical and radiographic findings of 25 patients with thoracolumbar fractures were prospectively presented to 5 groups of surgeons with disparate levels of training and experience with spinal trauma. These injuries were consecutively scored, first using the TLISS and then 3 months later with the TLICS. The recommended treatments proposed by the 2 schemes were compared with the actual management of each patient. Results. For both algorithms, the interrater kappa statistics of all subgroups (mechanism/morphology, status of the posterior ligaments, total score, predicted management) were within the range of moderate to substantial reproducibility (0.45–0.74), and there were no statistically significant differences noted between the respective kappa values. Interrater correlation was higher for the TLISS paradigm on mechanism/morphology, integrity of the posterior ligaments, and proposed management (P ≤ 0.01). The TLISS and TLICS schemes both exhibited excellent overall validity. Conclusions. Although both schemes were noted to have substantial reproducibility and validity, our results indicate the TLISS is more reliable than the TLICS, suggesting that the mechanism of trauma may be a more valuable parameter than fracture morphology for the classification and treatment thoracolumbar injuries. Since these injury characteristics are interrelated and are critical to the maintenance of spinal stability, we think that both concepts should be considered during the assessment and management of these patients.


World Journal of Emergency Surgery | 2009

ATLS® and damage control in spine trauma

Oliver I Schmidt; Ralf Gahr; Andreas Gosse; Christoph E. Heyde

Substantial inflammatory disturbances following major trauma have been found throughout the posttraumatic course of polytraumatized patients, which was confirmed in experimental models of trauma and in vitro settings. As a consequence, the principle of damage control surgery (DCS) has developed over the last two decades and has been successfully introduced in the treatment of severely injured patients. The aim of damage control surgery and orthopaedics (DCO) is to limit additional iatrogenic trauma in the vulnerable phase following major injury. Considering traumatic brain and acute lung injury, implants for quick stabilization like external fixators as well as decided surgical approaches with minimized potential for additional surgery-related impairment of the patients immunologic state have been developed and used widely. It is obvious, that a similar approach should be undertaken in the case of spinal trauma in the polytraumatized patient. Yet, few data on damage control spine surgery are published to so far, controlled trials are missing and spinal injury is addressed only secondarily in the broadly used ATLS® polytrauma algorithm. This article reviews the literature on spine trauma assessment and treatment in the polytrauma setting, gives hints on how to assess the spine trauma patient regarding to the ATLS® protocol and recommendations on therapeutic strategies in spinal injury in the polytraumatized patient.


Indian Journal of Orthopaedics | 2007

Role of early minimal-invasive spine fixation in acute thoracic and lumbar spine trauma

Oliver I. Schmidt; Sergej Strasser; Victoria Kaufmann; Ewald Strasser; Ralf Gahr

Polytraumatized patients following a severe trauma suffer from substantial disturbances of the immune system. Secondary organ dysfunction syndromes due to early hyperinflammation and late immunparalysis contribute to adverse outcome. Consequently the principle of damage control surgery / orthopedics developed in the last two decades to limit secondary iatrogenic insult in these patients. New percutaneous internal fixators provide implants for a damage control approach of spinal trauma in polytraumatized patients. The goal of this study is to evaluate the feasibility of minimal-invasive instrumentation in the setting of minor and major trauma and to discuss the potential benefits and drawbacks of this procedure. Materials and Methods: The present study is a prospective analysis of 76 consecutive patients (mean age 53.3 years) with thoracolumbar spine fractures following major or minor trauma from August 2003 to January 2007 who were subjected to minimal-invasive dorsal instrumentation using CD Horizon® Sextant™ Rod Insertion System and Longitude™ Rod Insertion System (Medtronic® Sofamor Danek). Perioperative and postoperative outcome measures including e.g. local and systemic complications were assessed and discussed. Results: Forty-nine patients (64.5%) suffered from minor trauma (Injury Severity Score <16). Polytraumatized patients (n=27; 35.5%) had associated chest (n=20) and traumatic brain injuries (n=22). For mono- and bisegmental dorsal instrumentation the Sextant™ was used in 60 patients, whereas in 16 longer ranging instrumentations the (prototype) Longitude™ system was implanted. Operation time was substantially lower than in conventional approach at minimum 22.5 min for Sextant and 36.2 min for Longitude™, respectively. Geriatric patients with high perioperative risk according to ASA classification benefited from the less invasive approach and lack of approach-related complications including no substantial blood loss. Conclusion: Low rate of approach-related complications in association with short operation time and virtually no blood loss is beneficial in the setting of polytraumatized patients regarding damage control orthopedics, as well as in geriatric patients with high perioperative risk. The minimal-invasive instrumentation of the spine is associated with beneficial outcome in a selected patient population.


World Journal of Emergency Surgery | 2007

Regional variability in use of a novel assessment of thoracolumbar spine fractures: United States versus international surgeons

John K. Ratliff; Neel Anand; Alexander R. Vaccaro; Moe R. Lim; Joon Y. Lee; Paul M. Arnold; James S. Harrop; Raja Rampersaud; Christopher M. Bono; Ralf Gahr

BackgroundConsiderable variability exists in clinical approaches to thoracolumbar fractures. Controversy in evaluation and nomenclature contribute to this confusion, with significant differences found between physicians, between different specialties, and in different geographic regions. A new classification system for thoracolumbar injuries, the Thoracolumbar Injury Severity Score (TLISS), was recently described by Vaccaro. No assessment of regional differences has been described. We report regional variability in use of the TLISS system between United States and non-US surgeons.MethodsTwenty-eight spine surgeons (8 neurosurgeons and 20 orthopedic surgeons) reviewed 56 clinical thoracolumbar injury case histories, which included pertinent imaging studies. Cases were classified and scored using the TLISS system. After a three month period, the case histories were re-ordered and the physicians repeated the exercise; 22 physicians completed both surveys and were used to assess intra-rater reliability. The reliability and treatment validity of the TLISS was assessed. Surgeons were grouped into US (n = 15) and non-US (n = 13) cohorts. Inter-rater (both within and between different geographic groups) and intra-rater reliability was assessed by percent agreement, Cohens kappa, kappa with linear weighting, and Spearmans rank-order correlation.ConclusionNon-US surgeons were found to have greater inter-rater reliability in injury mechanism, while agreement on neurological status and posterior ligamentous complex integrity tended to be higher among US surgeons. Inter-rater agreement on management was moderate, although it tended to be higher in US-surgeons. Inter-rater agreement between US and non-US surgeons was similar to within group inter-rater agreement for all categories. While intra-rater agreement for mechanism tended to be higher among US surgeons, intra-rater reliability for neurological status and PLC was slightly higher among non-US surgeons. Intra-rater reliability for management was substantial in both US and non-US surgeons. The TLISS incorporates generally accepted features of spinal injury assessment into a simple patient evaluation tool. The management recommendation of the treatment algorithm component of the TLISS shows good inter-rater and substantial intra-rater reliability in both non-US and US based spine surgeons. The TLISS may improve communication between health providers and may contribute to more efficient management of thoracolumbar injuries.


Topics in Spinal Cord Injury Rehabilitation | 2006

Percutaneous Internal Fixation of Thoracolumbar Spine Fractures

Ralf Gahr; Sergej Strasser; Ewald Strasser; Oliver I. Schmidt

Background: Prospective clinical outcome measures in a large cohort of patients with thoracolumbar spinal injuries have not been reported to date. Objective: To evaluate the outcomes of traumatic pathologic or nonpathologic thoracolumbar spine injuries treated with a percutaneous posterior internal fixation using the CD Horizon® Sextant™ Rod Insertion System (Medtronic® Sofamor Danek). Patients and Method: We performed a prospective clinical study evaluating a novel method of internal fixation of traumatic thoracolumbar spinal injuries. Over a 2-year period from August 2003 to July 2005, a total of 156 patients with thoracolumbar spinal injuries were treated with percutaneous posterior internal fixation using the CD Horizon® Sextant™ Rod Insertion System (Medtronic® Sofamor Danek). Indications for surgery included (1) AO Type A and Type B spinal fractures, (2) the presence of polytrauma, or (3) a pathologic traumatic fracture in the setting of osteoporosis or metastatic disease with or without prior anter...


GMS Interdisciplinary Plastic and Reconstructive Surgery DGPW | 2015

Perioperative management of patients with severe pulmonary hypertension in major orthopedic surgery: experience-based recommendations

Hans-Jürgen Seyfarth; Jochen Gille; Armin Sablotzki; Stefan Gerlach; Michael Malcharek; Andreas Gosse; Ralf Gahr; Elke G. Czeslick

Introduction: It is known that pulmonary hypertension is associated with worse outcome in both cardiac and non-cardiac surgery. The aims of our retrospective analysis were to evaluate the outcomes of our patients with pulmonary hypertension undergoing major orthopedic surgery and to give experience-based recommendations for the perioperative management. Material and methods: From 92 patients with pulmonary hypertension undergoing different kinds of surgical procedures from 2011–2014 in a tertiary academic hospital we evaluated 16 patients with major orthopedic surgery for perioperative morbidity and mortality. Results: Regarding the in-hospital morbidity and mortality, one patient died postoperatively due to pulmonary infection and right heart failure (6.25%) and 6 patients suffered significant postoperative complications (37.5%; bleeding = 1, infection = 1, wound healing deficits = 3; dysrhythmia = 1). Conclusion: Our data show that major orthopedic surgery is feasible with satisfactory outcome even in cases of severe pulmonary hypertension by an individualized, disease-adapted interdisciplinary treatment concept.


Archive | 2014

Trauma Surgery of the Extremities

Ralf Gahr; Matthias Spalteholz

Isolated injuries of the extremities are rarely life threatening. Under ATLS aspects in polytraumatized patient’s fractures of the extremities have to be approached differently from elective standards (e.g., external fixation). While axial stability, reconstruction of length, and weight bearing play an important part in the treatment of diaphyseal fractures of the long bones, articular injuries require most accurate and precise reconstruction of articular surfaces. Postoperative physiotherapy and rehabilitation are just as important for the final functional results as the operation itself.


Archive | 2014

Surgery of the Thoracolumbar Spine Trauma

Ralf Gahr; Matthias Spalteholz

Fifty percent of all relevant thoracic and lumbar spine injuries are located within the thoracolumbar junction T12–L2, due to the biomechanical transition from the stiff and rigid thoracic kyphosis to the highly mobile adjacent lordosis of the lumbar spine. In the mid-thoracic spine the spinal canal is very narrow in relation to the spinal cord. Already a compromise of the spinal canal of less than 20 % may lead to higher degrees of spinal cord injury. At the level of the thoracolumbar junction, the reserve space around the spinal cord is relatively wide so that even a spinal canal compromise of up to 40 % does not automatically lead to neurological deficits. The indication for surgery is dependent on neurological symptoms, mechanical instability, and deformity. According to the 3-column model of Denis, injuries of the anterior, middle, and posterior column are classified. The anterior column ensures load bearing while the posterior column acts as a dorsal tension band.


GMS Interdisciplinary Plastic and Reconstructive Surgery DGPW | 2014

Prone position in balloon kyphoplasty leads to no secondary vertebral compression fractures in osteoporotic spine - a MRI study.

Matthias Spalteholz; Evald Strasser; Torsten Hantel; Ralf Gahr

Purpose: Vertebral compression fractures are the most common fractures in the elderly. Long lasting pain and deformity is responsible for consecutive impairment with markedly reduced life quality, increased morbidity and mortality. The beneficial effects of balloon kyphoplasty are verified in many studies. Subsequent fracture risk is not finally clarified, cement related risks and deformity related risks are discussed. There is less knowledge about the risk of bone marrow edema and new fractures during balloon kyphoplasty procedure. The goal of this study is to examine, if prone position during kyphoplasty is an independent risk factor for new fractures in the osteoporotic spine. Methods: Consecutive MRI study of 20 patients with fresh, non-traumatic thoracolumbar vertebral compression fractures and balloon kyphoplasty treatment. MRI Scans of the thoracolumbar spine were obtained after surgery, before patients have been mobilized. Specific MRI changes like new bone marrow edema, signal intensity changes in adjacent and remote segments and new fractures were assessed by specialized neuro-radiologist. Results: 20 MR images were examined within 48 hours after balloon kyphoplasty procedure. 85% did not show bone marrow edema extent changes after kyphoplasty. We found minor increase of bone marrow edema within the augmented vertebral body in 3 cases. We did not find any new bone marrow edema and no new fractures in adjacent and remote segments after balloon kyphoplasty treatment. Conclusion: Prone position leads to no new bone marrow edema and no new fractures in the osteoporotic spine. Accordingly, prone position has no risk for adjacent level fractures in osteoporotic spines.


GMS Interdisciplinary Plastic and Reconstructive Surgery DGPW | 2013

External transpedicular spine fixation in severe spondylodiscitis - salvage procedure.

Matthias Spalteholz; Ralf Gahr

Specific and non-specific infections of the spine are rare. Due to their potential for severe instabilities, deformities and the impairment of neurological structures, the treatment is often prolonged and needs an interdisciplinary management. The clinical presentation is uncharacteristic, therefore diagnosis is often delayed. There are no prospective randomized studies for therapy recommendation. The surgical concept includes eradication of the infection and the reliable stabilization of involved segments. This concept is successful in most cases of endogenous vertebral osteomyelitis. The therapy of the exogenous spine infections after macro and micro surgery is more difficult, due to the critical wound situation and the involvement of the posterior parts of the spine. In these cases, infection-associated instability of the anterior part is complicated by critical posterior wound conditions. We present three cases of severe exogenous vertebral infections, where temporary external transpedicular spine fixation was used for salvage procedure, till soft tissue conditions have permitted a definitive internal stabilization.

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James S. Harrop

Thomas Jefferson University

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Christopher M. Bono

Brigham and Women's Hospital

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Neel Anand

Cedars-Sinai Medical Center

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Paul Anderson

Brigham and Women's Hospital

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