THE STRUCTURAL EFFECTS OF CONTINUOUS AND PULSED ELECTROMAGNETIC FIELD THERAPY ON HUMAN CARTILAGE EXPLANTS

osteoarthritis, fulfilling many of the characterist ics of a disease modifier in this disorder. The efficiency of the method is still under evaluat ion, aiming to find the optimal frequency, intensity and treatment duration. Fewer studies hav e followed the effects of PEMF on human articular explants, although the cartilage ma trix could play a role in the the biologic effects of these therapy by the means of type II co llagen piezoelectric properties. The present study aims to describe structural modificat ions induced by continuous and pulsed magnetic field on human articular explants resultin g from hip osteoarthritis patiens that benefitted from total hip arthroplasty. Ten osteoar tritis cartilages originating from the femural heads were obtained from patients who benefited from total hip arthroplasty. The joint cartilage from the non-portant region of the femoral head, with best microscopic aspect was detached by a cut tangential to the bone surface. The piece was then divided into 4 equal parts and transfered into 4 sterile contain ers filled with 10ml DMEM (Dulbecco’s Modified Eagle Medium) (Lonza), Penicillin 100UI/ml si Streptomycin 100 μg/ml (Lonza). Thus, four groups resulted. The fragments in the fi rst group (initial group) were histologically and histochemically analised by the safranin-orange coloration in less then 36 hours from the operation and quantified according t o osteoarthritis modified Mankin score. The fragments in the second group (control group) were incubated at 37 o C for 4 days, the fragments in the third group were incubated at 37 o C and treated with continuous magnetic field (CMF), with an intensity of 0,1mT, three hour s a day, for 4 days, and the fragments in fourth group were incubated in 37 o C and treated with PEMF with an intensity of 30mT, a frequency of 1.5Hz, three hours a day for 4 days. A t the end of the study, the fragments coming from the control, CMF, PEMF were also histologically and histochemically analised by the safranin orange coloration and quan tified according to osteoarthritis modified Mankin score.The modified Mankin score in the control group showed a worsening tendency versus the initial group (9.5 vs 8.95). In the CMF group the score had lower values compared to the control group (9.05 vs 9.5) and in the PEMF group, the score had even lower values than in the initial group (8. 7). Still, the differences between the groups were not statistically significant, the lowe st p was attained when comparing the PEMF group to the control group (p=0.27). The safranin orange coloration subscore in the control group had a worsening tendency when compared to the initial group (2.95 vs 2.5). In the CMF group the subscore had lower values than in the control group (2.65 vs 2.95) and in the PEMF group the subscore was lower even than in the initial group (2.45). The differences in the safranin orange coloration subsc ore were not statistically significant, the lowest p was found when comparing the control and the PEMF group (p=0.14) and when