Postoperative pain control is essential to recovery from total knee arthroplasty (TKA) because patients must bear weight on the new joint within 12 to 24 hours after surgery and begin physical therapy. Patients who underwent bilateral TKA recovered quicker when they received periarticular injections of analgesic medication as compared to a femoral nerve block, revealed a new study published in The Journal of the American Osteopathic Association.
For the study, researchers compared outcomes from two types of postoperative pain control methods in a group of patients who had both of their knees replaced. They reviewed records of 16 patients who underwent bilateral TKA in which a femoral nerve block was administered at the first operation and a periarticular injection of extended-release bupivacaine liposome mixture was used after the second operation. The same surgeon performed both TKAs in all patients studied. An average of 2.3 years separated the two procedures.
‘As periarticular injections allow patients to maintain control of the quadriceps muscles, recovery is better in patients who received these injections than the femoral nerve blocks. It also helped reduce the hospital stay, physical therapy sessions and total cost of surgery.’
Orthopedic surgeon, Brandon Horn, DO, of the McLaren Greater Lansing Medical Center in Michigan, said, "Periarticular injections, unlike femoral nerve blocks, allow patients to maintain control of the quadriceps muscles. The tenants of osteopathic medicine tell us that function follows form, so enabling the quadriceps to fully engage helps patients to get up and begin walking independently faster. There's also a preventative component at work, since femoral nerve blocks are also associated with a high incidence of postoperative falls."
Patients receiving a periarticular injection averaged 2.3 inpatient physical therapy sessions, compared to 3.5 inpatient physical therapy sessions for those receiving the femoral nerve block. The investigators also reported a half-day decrease in hospital stay. Those factors resulted in notable cost savings.
Dr. Horn said, "To treat knee replacement patients with a nerve block, you're looking at about $400 in additional costs for the procedure alone compared to that of the analgesic injection. Adding in the cost of additional physical therapy needed and extended hospital stay, the injection can save around $1,615 per patient."