Spinal intra-op. CFNB post-op. ~10-20% will have significant posterior knee pain and those get a single shot sciatic. Doing it this way means you avoid doing an extra procedure in 80-90% of your patients instead of giving a sciatic to everyone.
Epidurals just as good as CPNB but more side-effects and not great if you surgeons love the higher doses of LMWH.
With regards to DepoDur, take a look at the orginal articals for respiratory side-effects. Reasonably high rates of respiratory depression, hypoxia and opoid antagonist needs. I don't want a hypoxic or hypercapnic arrest because of something I did.
With regards to rehab, it is clear that pt's with continous nerve blocks have a better range of motion post rehab than PCA groups. The issue of how much "active movement" vs "passive movement" is required in the immediate post-op period for good long term results is yet to be determined. It is clear though that a patient in pain will do worse than a patient not in pain.
I personally think a femoral CPNB is standard of care for a TKA.
The artical that you may want to share with your surgeons is from way back in 1998:
http://www.anesthesia-analgesia.org/cgi/reprint/87/1/88
Anesth Analg. 1998 Jul;87(1):88-92.
Effects of intravenous patient-controlled analgesia with morphine, continuous epidural analgesia, and continuous three-in-one block on postoperative pain and knee rehabilitation after unilateral total knee arthroplasty.
Singelyn FJ, Deyaert M, Joris D, Pendeville E, Gouverneur JM.
Department of Anesthesiology, UCL School of Medicine, St. Luc Hospital, Brussels, Belgium.
In this study, we assessed the influence of three analgesic techniques on postoperative knee rehabilitation after total knee arthroplasty (TKA). Forty-five patients scheduled for elective TKA under general anesthesia were randomly divided into three groups. Postoperative analgesia was provided with i.v. patient-controlled analgesia (PCA) with morphine in Group A, continuous 3-in-1 block in Group B, and epidural analgesia in Group C. Immediately after surgery, the three groups started identical physical therapy regimens. Pain scores, supplemental analgesia, side effects, degree of maximal knee flexion, day of first walk, and duration of hospital stay were recorded. Patients in Groups B and C reported significantly lower pain scores than those in Group A. Supplemental analgesia was comparable in the three groups. Compared with Groups A and C, a significantly lower incidence of side effects was noted in Group B. Significantly better knee flexion (until 6 wk after surgery), faster ambulation, and shorter hospital stay were noted in Groups B and C. However, these benefits did not affect outcome at 3 mo. We conclude that, after TKA, continuous 3-in-1 block and epidural analgesia provide better pain relief and faster knee rehabilitation than i.v. PCA with morphine. Because it induces fewer side effects, continuous 3-in-1 block should be considered the technique of choice. Implications: In this study, we determined that, after total knee arthroplasty, loco-regional analgesic techniques (epidural analgesia or continuous 3-in-1 block) provide better pain relief and faster postoperative knee rehabilitation than i.v. patient-controlled analgesia with morphine. Because it causes fewer side effects than epidural analgesia, continuous 3-in-1 block is the technique of choice.
