Specific dynamics in vascular endothelial growth factors (VEGF) in blood of patients with vitamin D-resistant rickets during correction of multiplanar deformities of lower limbs

Abstract

Background Vitamin D-resistant rickets is a systemic disease with impaired bone remodeling that interferes with orthopaedic treatment of musculoskeletal pathologies. There is a paucity of literature focusing on the content and dynamics in vascular endothelial growth factors (VEGF) that promote the transformation of cartilage to bone. Objective Explore blood serum concentration of VEGF and VEGF-А and their receptors VEGF-R2, VEGF-R3 at stages of combined osteosynthesis in patients with vitamin D-resistant rickets during correction of multiplanar deformities of lower limbs. Material and methods The study included 24 patients with multiplanar deformities of lower limbs secondary to vitamin D-resistant rickets. Patients were treated with combined Ilizarov external fixation and intramedullary nailing using hydroxyapatite-coated wires. Serum concentration of VEGF and VEGF-А and their receptors VEGF-R2, VEGF-R3 were measured during treatment. Values obtained in the patients were compared to reference levels measured in 180 somatically healthy individuals. The quantified results were presented in a percentage of the reference values. Results Preoperative serum VEGF and VEGF-R2 concentration was significantly higher in the patients than that in normal subjects: VEGF, by 1990 % (р = 0.0033); VEGF-A, by 450 % (р = 0.00042); VEGF-R2, by 392 % (р = 0.0052) while preoperative serum VEGF-R3 concentration was lower by 68 % (p < 0.05) in the patients than that in subjectively healthy individuals. Surgical treatment resulted in greater increase in VEGF, VEGF-A levels with maximal concentration observed at the distraction phase. The opposite dynamics was observed with VEGF-R2 receptor. Specific dynamics was noted with VEGF-R3 receptor during surgical correction. Nearly preoperative serum concentration of VEGF-R3 was seen at the first stage showing the lowest level (21% of the normal) during bone distraction with external fixator and regenerate formation. It was reduced by 25 % of the preoperative level at the end of treatment. Conclusion Patients with vitamin D-resistant rickets demonstrated strong imbalance in serum concentrations of VEGFs and their receptors. Phase opposition dynamics in serum concentrations of VEGFs and their receptors was detected during surgical correction of multiplanar deformities of lower limbs.

Keywords

• vitamin d-resistant rickets
• multiplanar deformities of lower limbs
• correction
• ilizarov external fixation
• blood serum
• vascular endothelial growth factors and their receptors