Pain immediately following total knee arthroplasty (TKA) is often severe and can inhibit patients' rehabilitation. Recently, adductor canal blocks have been shown to provide adequate analgesia and spare quadriceps muscle strength in the early postoperative period. We devised a single injection motor sparing knee block (MSB) by targeting the adductor canal and lateral femoral cutaneous nerve with a posterior knee infiltration under ultrasound. Our primary objective was to evaluate the analgesia duration of the MSB in comparison to a standard periarticular infiltration (PAI) analgesia using patients' first rescue analgesia as the end point. Secondary outcomes measured were quadriceps muscle strength and length of stay. We randomised 82 patients scheduled for elective TKA to receive either the preoperative MSB (0.5% ropivacaine, 2.5ug/ml epinephrine, 10mg morphine, and 30mg ketorolac) or intraoperative periarticular infiltration (0.3% ropivacaine, 2.5ug/ml epinephrine, 10mg morphine, and 30mg ketorolac). Duration of analgesia, postoperative quadriceps power, and length of stay were evaluated postoperatively. Analgesic duration was found to be significantly different between groups. The MSB had a mean duration of 18.06 ± 1.68 hours while the PAI group had a mean duration of 9.25 ± 1.68 hours for a mean difference of 8.8 hours (95% CI 3.98 to 13.62), p<0.01. There were no significant differences between groups in quadriceps muscle strength power at 20 minutes (p=0.91) or 6 hours (p=0.66) after block administration. Length of stay was also not significantly different between the groups (p=0.29). Motor sparing blocks provide longer analgesia than patients receiving periarticular infiltration while not significantly reducing quadriceps muscle strength or increasing length of hospital stay

We recently performed a clinical trial comparing motor sparing blocks (MSB) to periarticular infiltration (PAI) following total knee arthroplasty (TKA). We found that MSBs provided longer analgesia (8.8 hours) than PAI with retention of quadriceps strength, and with similar function, satisfaction, and length of hospital stay. However, its potential increased cost could serve as a barrier to its adoption. Therefore, our aim was to compare the costs of MSBs to PAI following TKA. We conducted a retrospective review of data from our previous RCT. There were 82 patients included in the RCT (n=41 MSB group, n=41 PAI group). We compared the mean total costs associated with each group until hospital discharge including intervention costs, healthcare professional service fees, intraoperative medications, length of stay, and postoperative opioid use. Seventy patients were included (n=35 MSB group, n=35 PAI group). The mean total costs for the MSB group was significantly higher ($1959.46 ± 755.4) compared to the PAI group ($1616.25 ± 488.33), with a mean difference of $343.21 (95% CI = $73.28 to $664.11, p = 0.03). The total perioperative intervention costs for performing the MSB was also significantly higher however postoperative inpatient costs including length of stay and total opioid use did not differ significatnly. Motor sparing blocks had significantly higher mean total and perioperative costs compared to PAI with no significant difference in postoperative inpatient costs. However, its quadricep sparing nature and previously demonstrated prolonged postoperative analgesia can be used to facilitate an outpatient TKA pathway thereby offsetting its increased costs

Background. Post operative analgesia is an important part of Total Knee Arthroplasty (TKA) to facilitate early mobilisation and patient satisfaction. We investigated the effect of periarticular infiltration of the joint with chirocaine local anaesthetic (LA) on the requirement of analgesic in the first 24 hrs period post op. Methods. Retrospective analysis of case notes was carried out on 28 patients, who underwent TKA by two different surgeons. They were divided into two groups of 14 each; who did and did not receive the LA infiltration respectively. All patients were given spinal morphine (162 mcg r: 150-200). Analgesic requirement was assessed in terms of the amount of paracetamol, morphine, diclofenac, oxynorm and tramadol administered in 24hrs post op including the operating time. Results. Following results were obtained from patients receiving LA infiltration vs no infiltration: Morphine; 70 mg vs 200 mg, Paracetamol; 60 gm vs 58 gms, Diclofenac; 1650 mg vs 1050 mg, Oxynorm; 40 mg vs 80 mg, Tramadol; 200 mg vs 400 mg. Average length of stay (LOS) was 6 days (r: 3-8) in both groups. Conclusion. From this study it may be concluded that periarticular LA infiltration reduces the requirement of morphine in first 24 hrs by almost 1/3rd. The amount of tramadol and oxynorm was also halved in LA infiltrated group although the requirement of paracetamol remained the same. LA infiltrated group received almost 1.5 times more Diclofenac as compared to the non infiltrated group. The LOS was not affected by the administration of LA

Total hip arthroplasty (THA) is reliable and reproducible in relieving pain and improving function in patients with end-stage arthritis of the hip joint. With improvements in surgical technique and advances in implant and instrument design, there has been a shift in focus from the technical aspects of the surgical procedure to improving the overall patient experience. In addition, shifts in medico-economic trends placed a premium on early patient mobilization, early discharge, and maximizing patient satisfaction. Arguably, a single most important advance in arthroplasty over the past 2 decades has been the development of multimodal pain protocols that form the foundation of many of the rapid recovery protocols today. The principal concept of multimodal analgesia is pain reduction through the utilization of multiple agents that synergistically act at various nodes of the pain pathway, thus, minimizing patient exposure to each individual agent and opioids in order to prevent opioid related adverse events (ORAE). Regional anesthesia has been shown to reduce post-operative pain, morphine consumption, and nausea and vomiting compared to general anesthesia but not length of stay. Additionally, general anesthesia has been shown to be associated with increased rates of post-operative adverse events, The use of peripheral nerve blocks in the form of sciatic, femoral or fascia iliaca blocks have not been shown to significantly reduce post-operative pain compared to controls. Periarticular infiltration of local anesthetics has been shown in some settings to reduce pain during the immediate post-operative period (<24 h). However, no significant differences were noted in terms of early recovery or complications. The use of liposomal bupivacaine (LB) local infiltration decreased pain and shortened length of stay comparable to patients receiving a fascia iliaca compartment block, and has been shown in relatively few randomised trials to provide improved pain relief at 24 hours only compared to conventional bupivacaine. Continuous intra-articular infusion of bupivacaine after THA did not significantly further reduce post-operative pain compared to placebo. In summary, the use of regional anesthesia when appropriate along with local anesthetic infiltration in the setting of a robust multimodal pain protocol minimises pain and complications while maximizing patient satisfaction following THA

Dexmedetomidine, an alpha 2 agonist, has been approved for providing sedation in the intensive care unit. Along with sedative properties, it has analgesic activity through its highly selective action on alpha 2 receptors. Recent studies have examined the use of dexmedetomidine as an adjuvant to prolong the duration of peripheral nerve blocks. Studies showing effectiveness of dexmedetomidine for adductor canal block in knee surgery are small. Also, its effectiveness has not been compared to Epinephrine which is a strong alpha and beta receptor agonist. In a previous study, we showed that motor sparing knee blocks significantly increased the duration of analgesia compared with periarticular knee infiltration using local anesthetic mixture containing Epinephrine following total knee arthroplasty (TKA). In this study, we compared two local anesthetic mixtures: one containing Dexmedetomidine and the other Epinephrine for prolongation of motor sparing knee block in primary TKA patients. After local ethics board approval and gaining Notice of Compliance (NOC) from Health Canada for use of Dexmedetomidine perineurally, 70 patients between the ages 18 – 95 of ASA class I to III undergoing unilateral primary total knee arthroplasty were enrolled. Motor sparing knee block − 1) Adductor canal continuous catheter 2) Single shot Lateral Femoral Cutaneous Nerve block 3) Single shot posterior knee infiltration was performed in all patients using 60 ml mixture of 0.5% Ropivacaine, 10 mg Morphine, 30 mg Ketorolac. Patients randomized into the Dexmedetomidine group (D) received, in addition to the mixture, 1mcg/kg Dexmedetomidine and the Epinephrine (E) group received 200mcg in the mixture. The primary outcome was time to first rescue analgesia as a surrogate for duration of analgesia and secondary outcomes were NRS pain scores up to 24 hours and opioid consumption. The time to first rescue analgesia was not significantly different between Epinephrine and dexmedetomidine groups, Mean and SD 18.45 ± 12.98 hours vs 16.63 ± 11.80 hours with a mean difference of 1.82 hours (95% CI −4.54 to 8.18 hours) and p value of 0.57. Pain scores at 4, 6, 12, 18 and 24 hours were comparable between groups. Mean NRS pain scores Epinephrine vs Dexmedetomidine groups were 1.03 vs 0.80 at 4 hours, 1.48 vs 3.03 at 6 hours, 3.97 vs 4.93 at 12 hours, 5.31 vs 6.18 and 6.59 v 6.12 at 24 hours. Opioid consumption was also not statistically significant between both groups at 6, 12 18, 24 hours (p values 0.18, 0.88, 0.09, 0.64 respectively). Dexmedetomidine does not prolong the duration of knee motor sparing blocks when compared to Epinephrine for total knee arthroplasty. Pain scores and opioid consumption was also comparable in both groups. Further studies using higher dose of dexmedetomidine are warranted