[Pain therapy using stimulating catheters after total knee arthroplasty].

BACKGROUND: Epidural analgesia and continuous femoral nerve blocks are often used for pain therapy after total knee arthroplasty. The additional use of a continuous sciatic nerve block is controversially discussed. To avoid the problem of inaccurate placement a stimulating catheter may be useful. The aim of this study was to compare the effectiveness of a continuous femoral nerve block with an additional continuous sciatic nerve block for improved functional recovery and pain relief.

MATERIAL AND METHODS: An open randomized prospective controlled study was carried out with 54 patients to receive either a stimulating catheter placed in the femoral nerve sheath or two stimulating catheters placed in the femoral and in the sciatic nerve sheath or an epidural analgesia. Pain was recorded with the visual analogue scale at rest and with passive motion of the knee during the first 3 postoperative days. The angle of nearly pain-free bending of the knee, side effects and opioid consumption were recorded.

RESULTS: The reported pain scores and opioid consumption did not differ significantly between the groups. However, functional recovery up to the third postoperative day was significantly worse in the femoral catheter group.

CONCLUSION: Using stimulating catheters for pain therapy the three methods are largely comparable and other parameters should be used for individual selection.