Objective: This study aimed to investigate and compare the effects of naproxen (a nonselective nonsteroidal anti-inflammatory drug [NSAID]), celecoxib (a cyclooxygenase (COX)-2 selective NSAID), and acetaminophen (an analgesic with minimal anti-inflammatory activity) on tendon and tendon–bone healing following surgically induced supraspinatus tendon repair in a rat model. Methods: In this experimental study, 56 adult male Wistar Albino rats (mean weight, 300 g) were randomized into 4 groups (n=14 per group): control (1% methylcellulose vehicle), naproxen, celecoxib, and acetaminophen. A standardized full-thickness tear of the supraspinatus tendon was surgically created, and repair was performed using transosseous suture fixation through a humeral bone tunnel. Postoperative treatments were administered via oral gavage for 14 days. Tendon healing was assessed at 28 days through histological evaluation using modified Bonar scoring (n=6 per group) and biomechanical testing via uniaxial tensile assays (n=8 per group). Primary outcome measures included Bonar scores, maximum tensile strength, displacement, and stiffness. Results: The acetaminophen and control groups demonstrated superior maximum strength and stiffness compared to the NSAID-treated groups; however, these differences did not achieve statistical significance (maximum strength: P=.28; stiffness: P=.40). Histological analyses revealed significantly enhanced tendon–bone healing in the acetaminophen and control groups relative to the celecoxib and naproxen groups (P=.01). Conclusion: The early postoperative administration of COX-2 selective and nonselective NSAIDs may compromise early tendon-bone healing compared to acetaminophen. Although biomechanical differences were not statistically significant at 28 days, histological findings underscore the potential impact of analgesic selection on early postoperative tendon healing. Level of Evidence: N/A.Cite this article as: Bektaş E, Çelebi ME,Kurtulmuş T, Yılmaz F. Comparative effects of COX-2 selective and nonselective NSAIDs and acetaminophen on rotator cuff tendon–bone healing in a rat model. Acta Orthop Traumatol Turc., 2025;59(5):245-252.

Objective: This study aimed to investigate the effect of the low-intensity pulsed ultrasound (LIPUS) on the healing of Achilles tendinopathy in a rat model induced by type 1 collagenase. Methods: The study was conducted on 144 Achilles tendons of 72 Wistar albino female rats with typical activity and weighing 300-350 g. The model of Achilles tendinopathy was created by injecting type 1 collagenase. According to the sampling time, 4 groups served as the control group, while 8 groups received treatment at varying periods. Low-intensity pulsed ultrasound therapy was initiated in 8 groups at 1, 7, and 15 days. Treatment was extended for 1 and 2 weeks. Achilles tendons were removed from the treatment and control groups on the 15th, 21st, 30th, and 45th days for biomechanical and pathologic examination. Results: Compared to the control groups, LIPUS treatment administered in the first days of the proliferation phase increased tensile strength by approximately 30%, modulus of elasticity by approximately 53%, fibrillar appearance by 53%, and inflammation by 53%-33% in a shorter time. It was also demonstrated that starting treatment in the first days of the proliferation phase resulted in comparable success even with 1-week treatment compared to 2-week treatment. Conclusion: Low-intensity pulsed ultrasound therapy can provide positive results in managing Achilles tendinopathy in the rat model. Its capacity to shorten recuperation time has piqued the interest of conservative treatment approaches. As a result, more clinical research is required. Cite this article as: Kurtulmuş T, Çelebi ME, Bektaş E, Arican ÇD, Kucukyildirim BO, Demirkol M. Effect of the low-intensity pulsed ultrasound therapy on healing of Achilles tendinopathy in a rat model. Acta Orthop Traumatol Turc., 2024;58(2):102-109.

Background and Objectives: Courier-operated motorcycles and mopeds have become increasingly visible in urban traffic, raising concerns about injuries among both couriers and pedestrians struck by courier-operated vehicles. The study period coincided with the COVID-19 pandemic; however, this study was not designed to evaluate the effect of the pandemic on courier-related injuries. This multicenter retrospective study aimed to describe hospital-based injury patterns, injury severity, treatment requirements, complications, and mortality among selected courier-related casualties, including motorcycle couriers and pedestrians struck by courier-operated motorcycles or mopeds. Materials and Methods: This retrospective multicenter observational study included courier-related traffic casualties identified between 1 March 2020, and 1 June 2022, through nine hospitals in İstanbul and Ankara and, for fatal courier cases, linked emergency medical service and hospital records. The primary clinical cohort consisted of injured couriers and pedestrians evaluated or treated at participating hospitals. Linked prehospital and early fatal courier cases were analyzed separately for mortality-related and mechanism-specific fatality analyses. Injury severity was assessed using the New Injury Severity Score. Treatment was classified as conservative or surgical, including both fracture fixation and soft-tissue procedures. Results: A total of 857 courier-related traffic casualties were identified, including 491 couriers and 366 pedestrians. Among couriers, 111 fatal cases were verified through linked records. Clinical treatment and follow-up analyses were restricted to 380 hospital-treated surviving couriers and 366 pedestrians with available clinical records. In this selected hospital-treated courier cohort, multiple fractures, open fractures, higher injury severity scores, surgical treatment, and complications were more frequent than among pedestrians. All hospital-treated surviving couriers included in the orthopedic trauma cohort underwent surgery, reflecting the orthopedic trauma-based case-identification process, whereas most pedestrians were treated conservatively. Conclusions: Among this selected hospital-based cohort, courier casualties identified through hospital, trauma referral, emergency, forensic, and linked fatal-event records showed a more severe clinical profile than pedestrians evaluated after being struck by courier-operated motorcycles or mopeds. These findings should be interpreted as hospital-based injury-severity patterns rather than population-level estimates of accident incidence, relative injury risk, or public health burden.