Thankfully, the days of intramuscular injections (you know, the ones that hurt!) for post op pain relief are long gone. These days, in addition to epidural catheters and PCA pumps, there is another 'trick' that surgeons can use to improve patient's pain control.
The Q Ball system (also called other names by different manufacturers) is usually a clear, round rubber ball that has a catheter on one end (that goes into the operative site) and the ball on the other end. The device pumps local anesthetic medicine into the operative site for up to 5 days thus dramatically increasing the patient's comfort post op.
These devices are often used in orthopedic surgeries like total knee and hip replacements as well as spine surgeries.
If you're considering having surgery, ask your surgeon about the plan for post op pain control!