There is a paucity of large multi-institutional surveys to determine the prevalence of and risk factors for persistent pain after total hip (THR) and knee (TKR) replacements. We surveyed a variety of practices and patients and also correlated persistent pain with health-related quality-of-life outcomes. From October 10, 2007, to March 15, 2010, patients who had undergone primary THR or TKR with a minimum follow-up of 1 year were identified. A previously published questionnaire to identify persistent postsurgical pain that included a 36-item Short Form Health Survey was mailed to this group. Independent risk factors for persistent pain were identified with logistic regression. Responses from 1030 patients who underwent surgery at some point in time between June 13, 2006, and June 24, 2009, were analyzed (32% response rate). Forty-six percent of patients reported persistent pain (38% after THR and 53% after TKR) with a median average pain score of 3 of 10 and worst pain score of 5. Independent risk factors for persistent pain were female sex (odds ratio [OR], 1.23), younger age (OR, 0.97), prior surgery on hip or knee (OR, 1.39), knee versus hip replacement (OR, 1.65), lower-quality postsurgical pain control (OR, 0.9), and presence of pain in other areas of the body (OR, 2.09). All scores in the 36-item Short Form Health Survey were worse (8%-28% decrease) in patients with persistent postsurgical pain (P < 0.001). Persistent postsurgical pain is common after THR and TKR and is associated with reduced health-related quality of life, although our survey may be biased by the low response rate and retrospective recall bias. Nonmodifiable risk factors may lead to risk stratification. Severity of acute postoperative pain may be a modifiable risk factor.

BACKGROUND: Total knee arthroplasty is a painful surgery that requires early mobilization for successful joint function. Multimodal analgesia, including spinal analgesia, nerve blocks, periarticular infiltration (PI), opioids, and coanalgesics, has been shown to effectively manage postoperative pain. Both adductor canal (AC) and PI have been shown to manage pain without significantly impairing motor function. However, it is unclear which technique is most effective. This 3-arm trial examined the effect of AC block with PI (AC + PI) versus AC block only (AC) versus PI only (PI). The primary outcome was pain on walking at postoperative day (POD) 1. METHODS: One hundred fifty-one patients undergoing unilateral total knee arthroplasty were included. Patients received either AC block with 30 mL of 0.5% ropivacaine or sham block. PI was performed intraoperatively with a 110-mL normal saline solution containing 300 mg ropivacaine, 10 mg morphine, and 30 mg ketorolac. Those patients randomly assigned to AC only received normal saline knee infiltration. RESULTS: On POD 1, participants who received AC + PI reported significantly lower pain numeric rating scale scores on walking (3.3) compared with those who received AC (6.2) or PI (4.9) (P < 0.0001). Participants who received AC reported significantly higher pain scores at rest and knee bend compared with those who received AC + PI or PI (P < 0.0001). The difference in pain scores between participants who received AC + PI and those who received AC was 2.83 (95% confidence interval, 1.58–4.09) and the difference between those who received AC + PI and those who received PI was 1.61 (95% confidence interval, 0.37–2.86). On POD 2, participants who received AC + PI reported significantly less pain on walking (4.4) compared with those who received AC (5.6) or PI (5.6) (P = 0.006). On POD 2, there was no difference between the groups for pain at rest or knee bending. Participants who received AC used more IV patient-controlled analgesia on POD 0. There was no difference between the groups regarding distance walked. CONCLUSIONS: Participants who received AC + PI reported significantly less pain on walking on PODs 1 and 2 compared with those who received AC only or PI only.

Multimodal analgesia, including continuous femoral block, is often used to manage postoperative pain following total knee arthroplasty. To reduce the risk of deep vein thrombosis and pulmonary embolus formation, anticoagulation is also a part of the care for patients who undergo total knee arthroplasty. However, the concurrent use of continuous peripheral nerve block and anticoagulation can lead to hematoma formation. This prospective, single-center, observational study investigated the incidence of hematoma formation, causing neurovascular compromise, for patients with femoral catheters while taking the oral anticoagulant rivaroxaban. Five hundred four eligible patients consented to participate in this study. A femoral nerve block catheter was inserted before surgery, and a continuous infusion of local anesthetic was continued for 36 to 48 hours postoperatively. Rivaroxaban 10 mg was administered daily, and the femoral catheter was removed 20 hours after a dose of rivaroxaban. Participants were assessed daily to postoperative day 3 for the presence of a hematoma causing neurovascular compromise or ecchymosis formation at the femoral catheter site; sensory and motor functions of the femoral nerve were also assessed. No participant presented with a hematoma causing neurovascular compromise at the femoral catheter site or groin area (upper confidence limit, 3.7). The most common complication was an ecchymosis in the groin or upper thigh, with the highest incidence of ecchymosis formation occurring on postoperative day 3. In this prospective observational study, the concurrent administration of continuous femoral nerve block, the once-daily administration of the anticoagulant rivaroxaban, and the timed removal of the femoral catheter were not associated with hematoma formation resulting in neurovascular compromise at the femoral catheter insertion site or groin area.