Preoperative serum calcium could be a prognostic factor for surgical treatment of recurrent patellar dislocation: a retrospective study

Abstract

Background Surgical treatment for recurrent patellar dislocation (RPD) could yield good outcomes. While, unsatisfactory recovery still exists in some cases. For all prognostic factors, serum biomarkers have rarely been investigated. This study aimed to evaluate the prognostic value of preoperative serum calcium level, a widely used serum biomarker, in surgical treatment for RPD. Study design Retrospective study. Methods Ninety-nine patients with RPD were enrolled in the study. Preoperative serum calcium was acquired from routinely tested blood 1 day prior to operation. Demographic data, characteristics of RPD, postoperative functional outcomes were obtained. The association between preoperative calcium and postoperative functional outcomes (Kujala, Lysholm, Tegner, IKDC and KOOS score) was determined by correlation analysis and multivariate linear regression analysis. Poor recovery was determined as Kujala score below 80. The receiver operating characteristic (ROC) curve was used to assess the prognostic value of preoperative calcium. Results Patients were followed up for a mean period of 2.45 ± 1.33 years. All clinical scores showed significant improvement at the latest follow-up. Correlation and multivariate linear analyses indicated that serum calcium level was an important factor related with the prognosis of surgical treatment for RPD. According to the ROC curve, the cut-off value for preoperative calcium was 2.225 mmol/L. The clinical outcomes of patients with a preoperative blood calcium < 2.225 mmol/L was significantly worse than that with a higher calcium level. The correspondent sensitivity was 0.812 with a specificity of 0.633. Conclusion Operative treatment for RPD achieved good results, while in some cases the functional scores remain inferior. As a serum biomarker, preoperative calcium could be prognostic for outcomes after surgical treatment for RPD.

Effect of Lower Extremity Torsion on Clinical Outcomes After Medial Patellofemoral Ligament Reconstruction and Tibial Tubercle Transfer for Recurrent Patellofemoral Instability

“…Because the medial patellofemoral ligament (MPFL) is the principal passive constraint preventing lateral patellar translation, MPFL reconstruction (MPFLR), alone or combined with tibial tubercle transfer, has been validated to be an effective procedure for treating recurrent patellofemoral instability. 8,29 Nonetheless, a few risk factors have been reported to negatively affect the postoperative results of MPFLR, 16,33,37 including patella alta, high tibial tubercle-trochlear groove (TT-TG) distance, trochlear dysplasia, joint hyperlaxity, and lower limb axis malalignment. Among these factors, growing evidence indicates that lower extremity rotation might play an essential role.…”

“…Nonetheless, a few risk factors have been reported to negatively affect the postoperative results of MPFLR, 16,33,37 including patella alta, high tibial tubercle–trochlear groove (TT-TG) distance, trochlear dysplasia, joint hyperlaxity, and lower limb axis malalignment. Among these factors, growing evidence indicates that lower extremity rotation might play an essential role.…”

A Diagnosis of Vitamin D Deficiency Is Associated With Increased Rates of Primary Patellar Instability and Need for Recurrent Surgical Stabilization

“…One area of growing interest is the prognostic effects of serum biomarkers. 40 Current evidence suggests that lower preoperative serum calcium levels are associated with adverse clinical outcomes after surgical stabilization for recurrent patellar dislocations. 40 As such, another potential area of focus is hypovitaminosis D, a prevalent deficiency in the general population affecting more than 1 billion people globally.…”

“…40 Current evidence suggests that lower preoperative serum calcium levels are associated with adverse clinical outcomes after surgical stabilization for recurrent patellar dislocations. 40 As such, another potential area of focus is hypovitaminosis D, a prevalent deficiency in the general population affecting more than 1 billion people globally. 20 Several studies have established the micronutrient’s impact on bone mineralization, knee pain, skeletal muscle development, and soft tissue health.…”