Serum uric acid level is associated with the incidence of heterotopic ossification following elbow trauma surgery

Background Heterotopic ossification (HO) is a common complication after surgery for elbow trauma. Uric acid is the end product of purine metabolism and has several physiological and pathogenic roles. However, the relationship between HO and uric acid has not been explored. This retrospective study aimed to assess the relationship between HO and serum uric acid (SUA). Material and Methods We retrospectively reviewed data from 155 patients undergoing elbow trauma surgery in our hospital between January 2013 and December 2018. One hundred patients were included according to the inclusion criteria. They were divided into 2 groups according to the presence or absence of HO, and the SUA level was compared between groups using the independent samples t test. The optimal prognostic cutoff value was obtained using the maximum value of the Youden index. Results The SUA level was significantly higher in the HO group than in the non-HO group (362.0 ± 87.4 μmol/L vs. 318.3 ± 87.0 μmol/L; P < .05). Using the maximum value of Youden index, 317.5 μmol/L was determined to be the optimal SUA cutoff value for the prediction of HO, with a sensitivity of 68.75% (95% confidence interval [CI], 54.67%-80.05%) and specificity of 55.77% (95% CI, 42.34%-68.40%). Conclusions Our study was the first to find that the high SUA level is a risk factor for HO of the elbow joint after trauma. Moreover, 317.5 μmol/L is the SUA threshold predicting the occurrence and development of HO of the elbow, with high sensitivity and specificity. Heterotopic ossification (HO) is a common complication after surgery for elbow trauma. Uric acid is the end product of purine metabolism and has several physiological and pathogenic roles. However, the relationship between HO and uric acid has not been explored. This retrospective study aimed to assess the relationship between HO and serum uric acid (SUA). We retrospectively reviewed data from 155 patients undergoing elbow trauma surgery in our hospital between January 2013 and December 2018. One hundred patients were included according to the inclusion criteria. They were divided into 2 groups according to the presence or absence of HO, and the SUA level was compared between groups using the independent samples t test. The optimal prognostic cutoff value was obtained using the maximum value of the Youden index. The SUA level was significantly higher in the HO group than in the non-HO group (362.0 ± 87.4 μmol/L vs. 318.3 ± 87.0 μmol/L; P < .05). Using the maximum value of Youden index, 317.5 μmol/L was determined to be the optimal SUA cutoff value for the prediction of HO, with a sensitivity of 68.75% (95% confidence interval [CI], 54.67%-80.05%) and specificity of 55.77% (95% CI, 42.34%-68.40%). Our study was the first to find that the high SUA level is a risk factor for HO of the elbow joint after trauma. Moreover, 317.5 μmol/L is the SUA threshold predicting the occurrence and development of HO of the elbow, with high sensitivity and specificity.