Patrick Gahr

Dr. Patrick Gahr

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Research Focus & Metrics

Academic Career Length

4Years (2023-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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23 March 2023 in Frontiers in Surgery
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Journal Article
Open access
PGPatrick Gahr
Patrick Gahr
SKSebastian Kopf
Sebastian Kopf
SPStephan Pauly
Stephan Pauly
The management of proximal tibial fractures has evolved significantly in recent years. While the main goals of treatment – stability, restoration of the mechanical axis, and smooth articular surfaces – remain the same, methods have advanced substantially. In diagnostics, technical progress in CT and MR imaging has led to a better three-dimensional understanding of the injury. Newly developed classification systems such as the three-column concept of Luo et al. and the 10-segment concept of Krause et al. take this into account. Accordingly, there is a trend towards tailored approaches for particular fracture localizations. Parallel to this development, there is increasing evidence of the advantages of arthroscopically assisted surgical procedures. This Current Concepts article reviews classifications, diagnostics, treatment options as well as complications in fractures of the proximal tibia.

17 November 2023 in European Journal of Trauma and Emergency Surgery
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Journal Article
Open access
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PGPatrick Gahr
Patrick Gahr
TMThomas Mittlmeier
Thomas Mittlmeier
AGAnja Grau
Anja Grau
PHPhilipp K. E. Herlyn
Philipp K. E. Herlyn
ARAnja Rahn
Anja Rahn
DFDagmar-Christiane Fischer
Dagmar-Christiane Fischer
Purpose: Patients with tibial plateau fractures (TPF) are at risk of long-term hampered bipedal locomotion. A retrospective single-center study using patient-related outcome measures and a sophisticated assessment of walking abilities was conducted. Methods: Adults receiving surgical treatment of an isolated TPF between January 2012 and December 2016 received the KOOS questionnaire together with the invitation for an extensive follow-up examination on the clinical outcome including standardized assessment of the walking abilities (loadsol® system). Outcome was assessed relative to the severity of the injury or time to follow-up. Fractures were classified according to AO/OTA and Luo, respectively. Results: 58 out of 132 eligible patients filled in the questionnaire and participated at a median follow-up of 3.05 years after injury. For the categories “pain”, “mobility”, and “daily life activities”, all patients were rather satisfied and this was virtually not related to the time between fracture and assessment. Relevant limitations were reported for “sports and recreational activities” and “quality of life”. Loading of the previously fractured leg was most evidently changed on stairs and outdoor walking. Outcome was not related to either fracture type severity or time from injury. Conclusion: Outcome after an isolated TPF is neither related to fracture type, severity of the fracture nor time from injury. Simple gait analysis techniques relying on different tasks appear to yield a more sophisticated image on functional deficits after TPF than classical exam of ground-level walking and correlate quite well with validated patient-related outcome measures as the KOOS.

26 February 2024 in Diagnostics
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Journal Article
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GSGuido Schröder
Guido Schröder
TMThomas Mittlmeier
Thomas Mittlmeier
PGPatrick Gahr
Patrick Gahr
SUSahra Ulusoy
Sahra Ulusoy
LHLaura Hiepe
Laura Hiepe
HSHans-Christof Schober
Hans-Christof Schober
Background: Trabeculae in vertebral bodies are unequally distributed within the cervical spine (CS), the thoracic spine (TS), and lumbar spine (LS). Such structures are also unequally distributed within the individual vertebrae. Exact knowledge of the microstructure of these entities could impact our understanding and treatment of fractures caused by osteoporosis and possibly improve surgical approaches. Appropriate investigations could help clarify the pathomechanisms of different forms of osteoporotic vertebral fractures, as well as different changes in morphological findings like the trabecular bone score (TBS). In the present study, we applied punctures to the craniocaudal and ventrocaudal directions and obtained cylinders of cancellous bone from the central portions and marginal regions of cervical vertebrae 5 and 6, thoracic vertebrae 8 and 12, and lumbar vertebrae 1 and 3. We systematically analyzed these samples to determine the bone volume fraction, trabecular thickness, separation, connectivity density, degree of anisotropy, and structure model index. Methods: Using an 8-gauge Jamshidi needle, we obtained samples from three quadrants (Q I: right margin; Q II: central; Q III: left margin) in the frontal and transverse plane and prepared these samples with a moist cloth in a 1.5 mL Eppendorf reaction vessel. The investigations were performed on a micro-CT device (SKYSCAN 1172, RJL Micro & Analytic Company, Karlsdorf-Neuthard, Germany). All collected data were analyzed using the statistical software package SPSS (version 24.0, IBM Corp., Armonk, NY, USA). Student’s t test, the Wilcoxon–Mann–Whitney test, the Chi-squared test, and univariate analysis were used for between-group comparisons. The selection of the test depended on the number of investigated groups and the result of the Shapiro–Wilk test of normal distribution. In the case of statistically significant results, a post hoc LSD test was performed. Results: In total, we obtained 360 bone samples from 20 body donors. The craniocaudal puncture yielded data of similar magnitudes for all investigated parameters in all three quadrants, with the highest values observed in the CS. Comparisons of the ventrodorsal and craniocaudal microstructure revealed a significantly lower trabecular density and a significantly higher degree of anisotropy in the craniocaudal direction. Conclusions: The results presented different distributions and behaviors of trabecular density, with lower density in the mid-vertebral region over the entire breadth of the vertebrae. Reduced trabecular density caused a higher degree of anisotropy and was, therefore, associated with a lower capacity to sustain biomechanical loads. Fractures in fish vertebrae were easily explained by this phenomenon. The different changes in these structures could be responsible, in part, for the changes in the TBS determined using dual-energy X-ray absorptiometry. These results confirm the clinical relevance of the TBS.

22 September 2025 in Neuroradiology
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Journal Article
Open access
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Thomas BeyerThomas Beyer
Thomas Beyer
EVErik Volmer
Erik Volmer
PGPatrick Gahr
Patrick Gahr
MWMarc André Weber
Marc André Weber
Background: Traumatic vertebral fractures present a significant diagnostic challenge in emergency settings. Magnetic resonance imaging (MRI) excels in detecting bone marrow edema but faces practical limitations in acute trauma care. This prospective study evaluates the diagnostic accuracy of Dual-Energy Computed Tomography (DECT) in detecting traumatic vertebral bone marrow edema within a Level I trauma center environment. Methods: Between May 2020 and July 2023, 291 DECT examinations were performed on adult patients presenting with suspected or confirmed spinal injury. From these, 233 (80.1%) met quality criteria for analysis. A subgroup of 47 patients underwent additional MRI as reference standard, with 44 (93.6%) providing diagnostically evaluable images. Two board-certified radiologists independently assessed vertebral bone marrow edema presence in blinded, randomized evaluations using both modalities. Diagnostic parameters, examination times, radiation exposure, and cost-efficiency were analyzed. Results: DECT demonstrated an overall sensitivity of 82.9% and specificity of 96.6% for detecting vertebral bone marrow edema compared to MRI. The thoracolumbar junction showed highest sensitivity (91.7% for L3). DECT examination time was 7.2 minutes (including post-processing) versus 12 minutes for MRI, meaning MRI required 66.7% more time than DECT. DECT radiation exposure showed a mean dose-length product increase of only 3% compared to conventional CT. Body mass index showed no significant influence on DECT interpretability (p=0.196) or diagnostic accuracy except in isolated segments (L3, T11). Cost-benefit analysis revealed potential savings of 49.1% (€104.40) per spinal segment with DECT-based diagnostic pathways. Conclusion: DECT offers high diagnostic accuracy for detecting traumatic vertebral bone marrow edema with substantial time and cost advantages compared to MRI. The technique demonstrates particular value in acute trauma settings, while acknowledging limitations from artifacts (19.9% of cases) primarily caused by medical devices. These findings support implementing DECT as an efficient alternative to MRI in spinal trauma diagnostics.

3 December 2024 in Patient Safety in Surgery
Verified
Journal Article
Open access
PDF file
PGPatrick Gahr
Patrick Gahr
MMManuel Matthis
Manuel Matthis
LSLennart Schleese
Lennart Schleese
DFDagmar-C. Fischer
Dagmar-C. Fischer
TMThomas Mittlmeier
Thomas Mittlmeier
Background: The clinical benefit of locking plates in distal fibula fractures has not yet been proven. In addition, the risk of wound complications appears to be higher than with conventional tubular plates. We hypothesize that the benefits of locking plates in terms of biomechanical properties are outweighed by a higher risk of wound complications. Methods: We conducted a retrospective review of fibula fractures treated by osteosynthesis with either a conventional one-third tubular plate or an anatomically shaped locking plate from January 1, 2015 to December 31, 2021. We recorded baseline data and relevant comorbidities and defined the need for revision surgery due to wound-related or mechanical complications as primary endpoints. Results: A total of 595 out of 727 patients were eligible for our study. Of these 595 fractures, 526 were fixed with a one-third tubular plate, 69 with a locking plate. Revision surgery was required in 54 patients, in 51 cases due to wound complications. Three patients required revision surgery for mechanical reasons and all of them were younger than 40 years of age, have not been diagnosed with osteoporosis, but experienced complex fracture types. As the third tubular plate and locking plate groups differed in terms of age and comorbidities, we performed a 2:1 matching based on age and gender, leaving data from 138 patients receiving a third tubular plate. While the two groups were comparable in many aspects, the rate of wound complications was significantly higher in the locking plate group. Although the locking plate group had a higher percentage of diabetes mellitus, there was no correlation between this comorbidity and the higher revision rate in this group. Conclusions: Our data do not support the general use of locking plates in the treatment of distal fibular fractures. The risk of mechanical complications in osteoporotic ankle fractures seems to be overrated, as there were no mechanical revisions in the osteoporotic subgroup. The rate of wound-related revision surgery was significantly higher after the use of locking plates. This might be attributed to the greater thickness of locking plates.

29 July 2024 in Operative Orthopädie und Traumatologie
Verified
Journal Article
Closed access
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PGPatrick Gahr
Patrick Gahr
LSLennart Schleese
Lennart Schleese
TMThomas Mittlmeier
Thomas Mittlmeier