Cirrhosis is a risk factor for total hip arthroplasty for avascular necrosis: A Danish nationwide cohort study

Deleuran, Thomas; Overgaard, Søren; Vilstrup, Hendrik; Jepsen, Peter

Interpretation -Cirrhosis is a strong risk factor for avascular necrosis of the hip, but it is rare even in cirrhosis patients. â– Cirrhosis is the end-stage of all chronic liver diseases. It leads to a profound disturbance of the systemic circulation (Vallance and Moncada 1991) , of the immune response (Lin et al. 2007) , and of the coagulation system (Northup and Caldwell 2013) , but whether cirrhosis is a risk factor for joint disease has not been determined. Avascular necrosis (AVN) is bone necrosis caused by insuffi cient circulation, predominantly affecting bone parts with poor circulation: the femoral head and to a lesser extent the femoral condyles and carpal bones (Chang et al. 1993) . The pathogenesis of AVN remains poorly understood, but risk factors include tobacco smoking (Hirota et al. 1993 , Matsuo et al. 1988 ), corticosteroid treatment (Guo et al. 2014 ), alcoholism (Hirota et al. 1993 , Matsuo et al. 1988 ), fractures (Loizou and Parker 2009) , and certain other conditions (Mankin 1992) . Hung et al. (2011) reported that cirrhosis may also be a risk factor. Their study compared the risk of AVN in cirrhosis patients and that in an age-matched cohort of hospitalized patients with a high prevalence of conditions that predispose to AVN. They may therefore have underestimated the strength of the association. AVN is clinically signifi cant because many AVN patients require total hip arthroplasty (THA), and both AVN and cirrhosis are associated with an increased risk of complications after total hip arthroplasty (Bergh et al. 2014 , Jiang et al. 2014 , Deleuran et al. 2015 .