Effects of inhibition of bone resorption and cyclooxygenase on bone and tendon-to-bone healing: Experimental studies of fracture and tendon-to-bone healing in the rat

Treatment of fractures and ligament injuries often involves orthopedic surgery. In ligament reconstructions, firm tendon-to-bone healing is essential for stability. In fracture treatment, nonunion will significantly impair the outcome. Inhibitors of cyclooxygenase (COX) are effective against pain in orthopedic trauma but might impair bone healing. The aims of the thesis were to characterize tendon-bone healing and assess the effect of bone resorption inhibition by the bisphosphonate zoledronic acid (ZA). We also aimed to investigate the effect of short-time COX-inhibition by parecoxib on fracture healing. The studies conducted were all experimental animal studies in rats. The studies confirmed that tendon-to-bone tunnel healing is a slow process. A native layered tendon-bone interface did not recreate. Still, crossing collagen fibers were associated with an increase of biomechanical strength and bone mineral between 4 and 12 weeks of healing. The main effect of ZA was a reduction of tendon graft pull-out strength by 19% at early time points of healing. We found no negative impact of immediate or delayed three-days treatment with parecoxib on shaft fracture healing in rats

Helsesport og livskvalitet ved Beitostølen Helsesportsenter

Adapted physical activity and quality of life at Beitostølen Helsesportsenter Abstract Background: “Quality of Life” (QoL) is a difficult and therefore poorly defined term. There are different definitions used in questionnaires and by different actors in the field. The exercise at Beitostølen Helsesportsenter (BHSS) is not necessarily an optimization of function, as much as a thought of unity regarding the patient’s life, using adapted physical activity (APA) and sports as a tool. Material and method: 4 informants admitted to rehabilitation stays, were in depth interviewed at two different periods of times; during and 3 months after their stay. These data were analyzed using qualitative method. Results: In accordance with earlier studies at BHSS, we found that QoL can be affected in a positive way by rehabilitation at BHSS. In addition we learned about several factors of importance concerning QoL, especially that they differ a lot among patients. The different informants emphasize widely different subjects affecting their QoL. A quantitative research using questionnaires would not intercept these differences. Interpretation: Patients are unique, with different preferences and different needs. This requires an open, individual, qualitative approach to patients. They are entitled to an adjusted offer at those areas that will enhance their QoL. Our claim is that the use of qualitative method will find different and more correct answers to what QoL is to patients

Negative effect of zoledronic acid on tendon-to-bone healing: In vivo study of biomechanics and bone remodeling in a rat model

Background and purpose: Outcome after ligament reconstruction or tendon repair depends on secure tendon-to-bone healing. Increased osteoclastic activity resulting in local bone loss may contribute to delayed healing of the tendon–bone interface. The objective of this study was to evaluate the effect of the bisphosphonate zoledronic acid (ZA) on tendon-to-bone healing. Methods: Wistar rats (n = 92) had their right Achilles tendon cut proximally, pulled through a bone tunnel in the distal tibia and sutured anteriorly. After 1 week animals were randomized to receive a single dose of ZA (0.1 mg/kg IV) or control. Healing was evaluated at 3 and 6 weeks by mechanical testing, dual-energy X-ray absorptiometry and histology including immunohistochemical staining of osteoclasts. Results: ZA treatment resulted in 19% (95% CI 5–33%) lower pullout strength and 43% (95% CI 14–72%) lower stiffness of the tendon–bone interface, compared with control (2-way ANOVA; p = 0.009, p = 0.007). Administration of ZA did not affect bone mineral density (BMD) or bone mineral content (BMC). Histological analyses did not reveal differences in callus formation or osteoclasts between the study groups. Interpretation: ZA reduced pullout strength and stiffness of the tendon–bone interface. The study does not provide support for ZA as adjuvant treatment in tendon-to-bone healing