OBJECTIVETo investigate on the expression of some cytokines and other immunity makers right after the operation, the effect of femoral nailing on systemic immunity and sought to differentiate any differences between reamed and unreamed IMN.

METHODSFifty-nine patients presenting with acute femoral fractured including 55 male and 4 female, 32.1 years old on average, are divided into 2 group depend on ISS. All patients were treated by close reduction and intramedullary nail for fixation. In group 1, 23 reamed and 23 unreamed; in group 2, 7 reamed and 6 unreamed. Venous blood samples were taken at 24 hr pre-operationally, and 1 hr, 24 hr, 48 hr post operationally. Serum TNF, IL-6, IL-8, IL-10 were measured by enzyme-linked immunosorbent assay. CRP was measured by protein assay apparatus. We also collected venous samples from 22 healthy uninjured volunteers, which formed control group.

RESULTSAll immune marks were elevated post operation, for IL-6, IL-8, IL-10, this elevation began at 1 hr after operation, reached to the peak at 24 hr, and then down but never to the normal at 48 hr. For TNF and CRP, the level were raised at 24 hr, and then fallen at 48 hr. All mediators were raised significantly above the control group (< 0.05). Between reamed and unreamed patients both in group 1 and group 2, Although there was a trend towards higher levels of TNF, IL-6, IL-8, IL-10 and CRP in RFN than in the URFN, no significant difference was found except that there was a greater release of serum IL-10 in RFN than in URFN at 24 hr post operation (P = 0.047). Two patients have become SIRS, but the markers have shown no significant difference with those that have no SIRS symptoms.

CONCLUSIONSTo the patient not injured severely, using IMN for treatment will make the inflammatory mediators re-released on higher level than normal, which will be balanced by immunity itself soon, so IMN won't make any damage severely. And no significant difference were found between reamed and unreamed nail. But the changing of IL-10 show us that after IMN, especially the reamed nailing, the level of anti-inflammatory mediators will show the difference more apparently between RFN and URFN while the patient got injured more severely. Under this condition, the RFN will aggravate the restrain of immunity.