Despite continuous advances in the treatment of long bone fractures, disturbances of healing processes remain a difficult challenge. Currently, autologous cancellous bone and bone marrow grafting has become the standard treatment of delayed unions and non-unions. Platelet concentrates rich in growth factors – platelet-rich plasma (PRP) – represent a novel osteoinductive therapy that could be valuable for the treatment of disturbances of bone healing processes.

This article reports the efficiency of percutaneous autologous platelet-leukocyte rich gel (PLRG) injection as a minimally invasive method as alternative to open grafting techniques. Following the outpatient procedure, each of 32 participants was followed up on a regular basis with clinical examinations, roentgenograms, dual-energy x-ray absorptiometry (DEXA) examinations and functional evaluations. In the delayed-union group the average time to union after PLRG injection was 9,3 weeks and the union was achieved in all cases. In the nonunion group, the union was observed in 13 of 20 cases and the average time to union after PLRG injection was 10,3 weeks. Interestingly, in patients with non-union, who a union was not achieved, the ave time from the fracture and/or from the last operation was longer than 11 months. Probably the fibrous tissue in the gap interposing the bone ends becomes more ossified with time and the vascular vessels diminish, so the PLRG is no longer able to induce the bone healing processes in such cases.

This is our initial experience with the use of PLRG as biologic treatment for delayed union or nonunion. Our investigation showed that percutaneous PLRG injection in delayed union is a sufficient method to obtain union, which is less invasive procedure than bone marrow injection. Also percutaneous PLRG grafting can be an effective method for the treatment of selected cases of nonunion. One critical factor is the average time of PLRG injection to the index operation – the time less than 11 months after initial surgery seems to be critical to achieve good outcomes in percutaneous PLRG injections for nonunion.

Introduction: Platelets play a central role in hemostasis and healing processes. Upon their activation, platelet alfa-granules release over 30 cytokines including platelet-derived growth factor (PDGF), transforming growth factor-alfa (TGF-alfa), vascular endothelial growth factor (VEGF), insulin-like growth factor (IGF), epidermal growth factor (EGF) and also active substances like serotonin, catecholamines, von Willebrand factor, proaccelerin, osteonectin and antimicrobial proteins. By concentrating platelets, platelet-rich plasma (PRP) with higher levels of growth factors might be reached, which could stimulate the healing processes. The activator for PRP is a mixture of thrombin and calcium chloride. After connecting these substances platelet-rich gel (PRG) is formed.

Aims: In present study, we investigated in vitro antimicrobial activity of PRG after antibiotic administration.

Material and Methods: 30 minutes after iv Amoxillin/ clavulanic acid administration 54 ml of whole blood was collected from each of 10 donors. PRPs were prepared with using GPS system from Biomet. In vitro laboratory susceptibility to PRG was determined by the Kirby-Bauer disc diffusion method on Mueller-Hinton agar (Becton Dickinson). Baseline antimicrobial activity was assessed by measuring the zones of inhibition. Agar plates were coated with one of the following strain: Staphylococcus aureus ATCC 43300 (MRSA), Staphylococcus aureus ATCC 25923 (MSSA), Klebsiella pneumoniae ATCC 700603 (ESBL), Escherichia coli ATCC 35218 (ESBL), Escherichia coli ATCC 25922, Enterococcus faecalis ATCC 29212 and Pseudomonas aeruginosa ATCC 27853.

Results: We tested 10 samples of PRG. Zones of inhibition produced by PRG ranged between 6 – 23 mm in diameter. PRG inhibited the growth of Staphylococcus aureus. PG also was active against Escherichia coli, Enterococcus faecalis. No activity against Klebsiella pneumoniae and Pseudomonas aeruginosa was detected.

Conclusions: Our previous study showed PRG no activity against Enterococcus faecalis without antibiotic administration. In this investigation we observed PRG strong activity against this bacteria after iv Amoxicillin-clavulanic acid administration. In infections during antibiotic treatment, PRG antimicrobial properties are enhanced by antibiotics that are concentrated in plasma.