Experimental study of tendon healing early phase: is IGF-1 expression influenced by platelet rich plasma gel?

BACKGROUND: It is well established that growth factors play a critical role in the healing process of connective tissues. To our knowledge, there are no studies in literature concerning the influence of PRP on growth factors expression. HYPOTHESIS: The aim of this study was to assess the effect of a single application of platelet rich plasma (PRP) gel in a patellar tendon defect on the spatial and temporal expression of Insulin-like Growth Factor 1 (IGF-1) during tendon healing. MATERIALS AND METHODS: Twenty-four animals were randomized to receive PRP (PRPFast, Bioteck) in a gel form (PRP group) and 24 to serve as untreated controls (Control group). A defect of 3 mm x 10 mm was surgically created on the tendon under general anaesthetic and in the PRP group, PRP gel was applied to fill the tendon defect whereas no treatment was applied in the control group. Six animals (12 limbs) from each treatment-group were sacrificed after one, two, three and four weeks following treatment. Histological and immunohistochemical staining were performed. RESULTS: Histology revealed a faster healing process in the tendons of PRP group in comparison with the controls. In the first 2 weeks of healing, IGF-1 was found intracellularly in various type cells, whereas in the last 2 weeks of healing, IGF-1 was detected mainly in tenocytes. Both cytoplasmic and nuclear expressions were present, whereas the larger amounts of immunoexpression were localized in both epitenon and endotenon. A superior expression of IGF-1 was seen in PRP group compared with controls (p<0.0001) in both the epitenon and endotenon at each time point except at 4th week of healing where a superior expression of IGF-1 was shown in the endotenon of control group, compared to the PRP group (p<0.0001). CONCLUSION: PRP may improve tendon defect healing by overexpression of IGF-1. LEVEL OF EVIDENCE: Laboratory control animal study.

The use of autologous PRP gel as an aid in the management of acute trauma wounds.

Autologous platelet-rich plasma (PRP) gel is increasingly used in the treatment of a variety of soft and bony tissue defects, such as accelerating bone formation and in the management of chronic non-healing wounds. We performed this study to assess the benefits of using autologous PRP gel in the treatment of acute limb soft tissue wounds. 59 patients with acute wounds (open fractures, closed fractures with skin necrosis and friction burns) were randomised into two groups. Group A (32 patients) were treated with conventional dressings and Group B (27 patients) were managed with local application of PRP gel. Gustillo grade IIIb or IIIc open fractures were not included in this study, as these injuries required coverage with flap. The clinical endpoints were the healing rate and/or the time required to bring about adequate tissue regeneration in order to undergo reconstructive plastic surgery. The rate of wound healing rate was significantly faster in Group B at week 1, 2 and 3 (p=0.003, p<0.001 and p<0.001, respectively). The mean time to plastic reconstruction in Group B was 21.26 days, S.D.=1.35 vs 40.6 days in Group A, S.D.=5.27 (p<0.001). This study has shown that PRP gel treatment can be a valuable and effective aid in the management of acute trauma wounds.

Internal fixation of proximal humerus fractures using the Polarus intramedullary nail.

INTRODUCTION: It has been stated that proximal humeral fractures are the last unsolved fractures in orthopedics. In this study, we evaluate the results of the Polarus nail, in order to constitute to the controversial problem of the treatment of proximal humerus fractures. PATIENTS AND METHODS: Between 2003 and 2005, 27 patients with severely displaced proximal humeral fractures were treated with the Polarus intramedullary system. The fractures were classified according to the Neer classification system. There were 16 2-part fractures and 11 3-part fractures. At the 12-months follow up we graded the clinical outcome of the patients according to the Neer scoring system. RESULTS: The duration from time of injury to operation ranged from 1 to 6 days. The mean operative time was 55 min and no need of blood transfusion was recorded. Bony union was obtained in 27 patients. There were no cases of nonunion and the period from operation to the appearance of sufficient bridging callus on radiographs was 5-11 weeks (mean 6 weeks). In one patient, a backed-out proximal screw was recorded. Stiffness of the shoulder was seen in one patient and avascular necrosis of the head of humerus in another. Related to the clinical outcome, six patients had an excellent result, 15 patients had a satisfactory result, four patients had an unsatisfactory result, and two patients had a poor result. The 77.78% of the patients had an excellent or satisfactory clinical outcome. There was significant difference in the functional outcome between patients younger than 65 years (91.55) and those older than 65 years (80.22) (P < 0.05). No significant difference was recorded in the Neer score between the patients with a 2-part fracture and the patients with a 3-part fracture (80.18) (P > 0.05). CONCLUSION: The Polarus nail is designed to provide stable fixation with a straightforward insertion and targeting procedure. The fact that 77.78% of the patients had an excellent or satisfactory clinical outcome, suggest that Polarus humeral rod system can be a worthy alternative to traditional operative methods for displaced proximal fractures of the humerus.

Effect of an inactivated Parapoxvirus based immunomodulator (Baypamun) on post weaning diarrhoea syndrome and wasting pig syndrome of piglets.

Post weaning diarrhoea syndrome (PWDS) and wasting pig syndrome (WPS) are two entities of the pig industry induced by stress factors occurring at the early weaning and further complicated by opportunistic pathogens. In the present paper we examine--through one pilot and one final trial--whether prevention of these two syndromes can be achieved in the field by immunomodulation of the pig e.g., by improving its non-specific immunological response. In both trials two groups of early weaned piglets were submitted to the treatments. In the pilot trial the first group received no treatment and served as controls and the animals of the second group were injected twice with an inactivated Parapoxvirus based immunomodulator (Baypamun, Bayer, Germany). In the final trial the first group of piglets received no treatment and served as a control group. The animals of the second group were injected twice with a freeze-dried immunomodulator (Baypamun). Piglets were compared with regard to the severity of PWS, mortality, growth performance parameters, and for the presence of pathogens in their faeces. The results have shown that Baypamun treated piglets performed significantly better than negative control piglets in all the parameters examined. It was concluded that stimulation of the non-specific immunity of piglets may be helpful in preventing the appearance of PWDS and WPS in the field.