Fracture-related infection in osteoporotic bone causes more severe infection and further delays healing

Bone & Joint Research

article

Jie Li¹  Ronald Man Yeung Wong¹  Yik Lok Chung¹  Sharon Shui Yee Leung²  Simon Kwoon-Ho Chow¹  Margaret Ip³  Wing-Hoi Cheung¹ 

[1] Department of Orthopaedics & Traumatology, The Chinese University of Hong Kong;School of Pharmacy, The Chinese University of Hong Kong;Department of Microbiology, Prince of Wales Hospital, The Chinese University of Hong Kong

关键词: Fracture healing;    Osteoporosis;    Fracture related infection;    osteoporotic bone;    infection;    Fracture-related infection (FRI);    antibiotics;    Cortical bone;    staining;    systemic antibiotics;    rat model;    bone lysis;   

DOI  :  10.1302/2046-3758.112.BJR-2021-0299.R1

学科分类：骨科学

来源: British Editorial Society Of Bone And Joint Surgery

【 摘 要 】

AimsWith the ageing population, fragility fractures have become one of the most common conditions. The objective of this study was to investigate whether microbiological outcomes and fracture-healing in osteoporotic bone is worse than normal bone with fracture-related infection (FRI).MethodsA total of 120 six-month-old Sprague-Dawley (SD) rats were randomized to six groups: Sham, sham + infection (Sham-Inf), sham with infection + antibiotics (Sham-Inf-A), ovariectomized (OVX), OVX + infection (OVX-Inf), and OVX + infection + antibiotics (OVX-Inf-A). Open femoral diaphysis fractures with Kirschner wire fixation were performed. Staphylococcus aureus at 4 × 104 colony-forming units (CFU)/ml was inoculated. Rats were euthanized at four and eight weeks post-surgery. Radiography, micro-CT, haematoxylin-eosin, mechanical testing, immunohistochemistry (IHC), gram staining, agar plating, crystal violet staining, and scanning electron microscopy were performed.ResultsAgar plating analysis revealed a higher bacterial load in bone (p = 0.002), and gram staining showed higher cortical bone colonization (p = 0.039) in OVX-Inf compared to Sham-Inf. OVX-Inf showed significantly increased callus area (p = 0.013), but decreased high-density bone volume (p = 0.023) compared to Sham-Inf. IHC staining showed a significantly increased expression of TNF-α in OVX-Inf compared to OVX (p = 0.049). Significantly reduced bacterial load on bone (p = 0.001), enhanced ultimate load (p = 0.001), and energy to failure were observed in Sham-Inf-A compared to Sham-Inf (p = 0.028), but not in OVX-Inf-A compared to OVX-Inf.ConclusionIn osteoporotic bone with FRI, infection was more severe with more bone lysis and higher bacterial load, and fracture-healing was further delayed. Systemic antibiotics significantly reduced bacterial load and enhanced callus quality and strength in normal bone with FRI, but not in osteoporotic bone.

【 授权许可】

CC BY-NC