gms | German Medical Science

Objectives: In this study, I investigated the efficiency of different local anesthetic application methods on the early first day period for pain control of total knee arthroplasty (TKA). Although opioids and continuous epidural analgesia are still the major treatments for post-op pain management of total knee arthroplasty, local anesthetics have the advantage of minimizing pain in the origin and they also have minimal side effects. One-shot femoral block for the treatment of post-op pain of TKA supplies enough pain relief of anterior side of knee but there is still severe pain in the posterior part of the knees. This was because the posterior part of knee is innervated by sciatic and obturator nerves and their branches. The osteotomy segments of knee are also innervated by the sciatic nerve from S1 root.I used 50 cc local anesthetics intraoperatively.

Methods: All the subjects in this study were operated by the seniour author for tka with lumbar spinal anethesia for the treatment of osteoarthritis and were randomly chosen for the four different post-op pain treatment groups. None of the demographic data (age,weight,gender distribution) differed significantly among these four groups. There were fifty patients in each group.The first group (group A) was followed up without any local anesthetic medication to examine the consistency of spinal anesthesia after the operation as a control group. The second group (group B) was treated by applying only one-shot femoral block after the operation in the operating room, The third group (group C) received only intraoperative local anesthetics to knee and group D received intraop local anesthetics in addition to the femoral block.I also used visual analog scale (VAS) to assess the intensity of pain, on which zero was equivalent to “no pain” and 100 mm was to the “worst pain”. I also asked each patient their pain levels by using VAS scala when the patient needed medication.

In this study I named a new data painless time (PT) to determine the efficiency of pain treatments and to compare the success rates in each group. To calculate the PT's we recorded the two time points. The first time point was when the patient left surgery room and the second was when the patient needed and wanted post-op pain medication. Then I got the substraction of these two time points and named the result time as Painless time (PT) in hours.

Results and Conclusion: The mean of PT was 10.5 hours in group D which was better than group A(3.2hours) ,B(6.2hours) and C(6.8 hours).It was statistically important. (p<0.001) .Group D had the least intensity of pain (VAS score), when the nurse was called for pain medication (p<0.001).Group D patients mostly expressed slight pain which can be treated by applying only 20 mg of tenoksicam which is a non steroid antienflamatuar drug.Only five patients needed opioids .

I conclude that intraop local anesthetic application in addition to one shot femoral block is en effective treatment of TKA pain.