25dkou108 10.3205/25dkou108 urn:nbn:de:0183-25dkou1085 Meeting Abstract Schaefer Schaefer Daniel Alexander Klaus DAK

BG Klinik Tübingen, Clinic for Trauma and Reconstructive Surgery, Eberhards Karls University Tübingen, Tübingen, Deutschland

author Stief Stief Maximilian M

Saarland University, Clinical-Experimental Surgery, Homburg, Germany, Homburg, Deutschland

author Menger Menger Michael M

Saarland University, Clinical-Experimental Surgery, Homburg, Germany, Homburg, Deutschland

author Laschke Laschke Matthias M

Saarland University, Clinical-Experimental Surgery, Homburg, Germany, Homburg, Deutschland

author Braun Braun Benedikt B

BG Klinik Tübingen, Clinic for Trauma and Reconstructive Surgery, Eberhards Karls University Tübingen, Tübingen, Deutschland

author Rollmann Rollmann Mika M

BG Klinik Tübingen, Clinic for Trauma and Reconstructive Surgery, Eberhards Karls University Tübingen, Homburg, Deutschland

author Herath Herath Steven S

BG Klinik Tübingen, Clinic for Trauma and Reconstructive Surgery, Eberhards Karls University Tübingen, Tübingen, Deutschland

author Histing Histing Tina T

BG Klinik Tübingen, Clinic for Trauma and Reconstructive Surgery, Eberhards Karls University Tübingen, Tübingen, Deutschland

author Menger Menger Maximilian M

BG Klinik Tübingen, Clinic for Trauma and Reconstructive Surgery, Eberhards Karls University Tübingen, Tübingen, Deutschland

author German Medical Science GMS Publishing House

Düsseldorf

610 20251031 engl This is an Open Access article distributed under the terms of the Creative Commons Attribution 4.0 License. Dieser Artikel ist ein Open-Access-Artikel und steht unter den Lizenzbedingungen der Creative Commons Attribution 4.0 License (Namensnennung). M0634 108 Deutsche Gesellschaft für Orthopädie und Unfallchirurgie Deutsche Gesellschaft für Orthopädie und Orthopädische Chirurgie Deutsche Gesellschaft für Unfallchirurgie Berufsverband für Orthopädie und Unfallchirurgie Deutscher Kongress für Orthopädie und Unfallchirurgie (DKOU 2025) Poster | Grundlagenforschung 2 Berlin 20251028 20251031 AB20-4413 TextObjectives and questions: For the management of post-injury pain in aged patients Diclofenac, a nonsteroidal anti-inflammatory drug (NSAID), accounts to the most prescribed analgesic medications. However, NSAIDs negatively affect fracture healing. Additionally, recent research highlights potential differences in drug effects between male and female patients. Hence, we examined the effects of diclofenac treatment on fracture healing in aged male and female mice using a closed femoral fracture model.Material and methods: In this study the influence of diclofenac on fracture healing was studied in aged CD-1 mice (16–18 months) using a femoral fracture model with intramedullary screw fixation. Treatment started the day of surgery. Mice received a daily dose of diclofenac (D) (intraperitoneal (i.p.) injection of 5 mg/kg body weight, male: n= 11, female n =14) or vehicle (C) (NaCl, male: n = 11; female n = 12) for durations of 2 and 5 weeks, respectively. Fracture healing was analyzed by X-ray imaging, biomechanics, micro-computed tomography (CT), histology and histomorphometry. Data are expressed as mean ± SEM. Statistical differences between the groups were assessed using Student’s t-test. Statistical significance was accepted for p<0.05.Results: Our results showed a significant decrease in bending stiffness at 5 weeks post-surgery in aged male mice (D: 16.9% ± 4.0 vs. C: 53.1% ± 14.1 (p≤0.037) to contralateral femur). This reduction was less pronounced in aged female mice (D: 34.1 ± 7.1 in % vs. C: 46.9 ± 10.7 (p<0.0001) contralateral femur). These differences were associated with a lower amount of bone tissue and significantly higher amounts of fibrous tissue in the callus of aged male CD-1 mice. Furthermore, the number of tartrate-resistant acid phosphatase (TRAP)-positive osteoclasts within the callus was significantly higher in diclofenac-treated aged male mice at 5 weeks after surgery compared to controls (D: 3.7 ± 0.3 vs. C: 2.6 ± 0.3 (p=0.0242) osteoclasts/high power field (HPF)). Interestingly, this increase in the number of osteoclasts was not observed in aged female mice (D: 2.3 ± 0.5 vs. C: 2.9 ± 0.3 (p≤0.405) osteoclasts/HPF).Discussion and conclusions: This study shows that male aged CD-1 mice suffer from a more pronounced impairment of fracture healing after diclofenac treatment when compared to female aged mice. This could be attributed to an excessive overshooting osteoclast response at the late stage of fracture healing in aged male mice. These findings indicate that diclofenac treatment in aged male patients should be avoided during fracture healing. 0 0 0 0