Introduction. Knee osteoarthritis is a leading cause of disability around the world. Traditionally, total knee arthroplasty (TKA) is the gold standard treatment; however, unicompartmental knee arthroplasty (UKA) has emerged as a less-invasive alternative to TKA. Patients with UKAs participate earlier with physical therapy (PT), have decreased complications, and faster discharges (1, 2). As UKA has evolved, so has computer navigation and robotic technology. The Robotic Assisted UKA combines the less invasive approach of the UKA with accurate and reproducible alignment offered by a robotic interface (3)(Figure1). A key part of a patient's satisfaction is perioperative pain control. Femoral nerve blocks (FNB) are commonly performed to provide analgesia, though they cause quadriceps weakness which limits PT (4). An alternative is the adductor canal block (ACB) which provides analgesia while limiting quadriceps weakness (4). The adductor canal is an aponeurotic structure in the middle third of the thigh containing the femoral artery and vein, and several nerves innervating the knee joint including the saphenous nerve, nerve to the vastus medialis, medial femoral cutaneous nerve, posterior branch and occasionally the anterior branch of the obturator nerve (5). In a multi-modal approach with Orthopedic Surgery, Regional Anesthesia, and PT departments, an early goal directed plan of care was developed to study ACB in UKA with a focus on analgesia effectiveness and PT compliance rates. Methods. Following IRB approval, we performed a case series including 29 patients who received a single shot ACB. Primary outcomes were distance walked with PT on postoperative day (POD) 0 and 1 and discharge day. Our secondary outcomes included Visual Analog Scale (VAS) scores in the post-anesthesia care unit (PACU), 8 and 24 hours postoperatively and oral morphine equivalents required for breakthrough pain. Results. All patients received PT prior to discharge. With respect to distance walked, the median distance on POD 0 was 26 feet (IQR 9–66), and on POD 1 was 128 feet (IQR of 80–200), and the median day of discharge was POD 1 (IQR 0–2). In this study, the patients’ median age was 64 (IQR 59–69) and the median BMI was 31 kg/m2 (IQR 22–41). The median VAS score in the PACU was 1 (IQR 0–7). The VAS scores for 8 and 24 hours were 5 (IQR 2–7) and 5 (IQR 2.7–7). Median oral morphine equivalents required for breakthrough pain were 99.5 mg (IQR 67.5–150.5 mg) (Figure 3). Conclusion. This case series supports that a single shot ACB facilitates early PT and hospital discharge in patients post UKA

Background. Exparel (Pacira Pharmaceuticals, Parsippany, NJ, USA) is a long-acting liposomal Bupivacaine extended release compound that can be used as peri-articular injection (PAI) or regional nerve block. The purpose of this study was to compare the post-operative analgesic efficacy of Exparel as a single administration adductor canal block (ACB) varsus PAI. Methods. From May 2016 to June of 2017, 70 patients with primary knee osteoarthritis undergoing unilateral knee replacement were prospectively randomized into two cohorts: 1) PAI (Exparel 266 mg (20 ml vial) with 20 ml of 0.5% bupivacaine HCl, and normal saline to a total volume of 120 ml); 2) ACB (Subsartorial saphenous nerve using Exparel 266 mg in 20 ml vial). All patents underwent spinal anesthesia with comprehensive pre-emptive and postoperative multimodal pain protocol. All opioids given were converted to morphine equivalents. Pain was recorded at 4 – 12 hrs (day of surgery), post-operative day (POD) 1, 2, and 3 after surgery. Results. There was no statistical significance between the pain scores during the first 12 hrs (day 0) after surgery. We found a trend towards a significance on POD # 1, as PAI group had less pain (5.3 vs 4.2, p=0.09). The mean pain score in ACB group increased on POD # 3 while in PAI continued a decrease (4.8 vs 1.8, p=0.03). There was no statistical significance between the 2 groups regarding the accumulative daily converted Morphine equivalent consumption or total consumption. Conclusion. We found similar results between PAI and ACB using Exparel after TKA up to 48 hours

Introduction. The regionalisation of major trauma in the UK has significantly improved outcomes for patients with severe, lower limb injuries. Chronic pain after complex lower limb injuries is well documented, but seems to remain a problem despite better clinical and radiological outcomes. We hypothesised that pain was mediated through the saphenous nerve, especially as most tibial injuries affected the soft tissues medially. As a proof of concept, we undertook adductor canal blocks to understand pain aetiology. Materials & Methods. Patients with chronic pain following complex lower limb trauma or congenital deformity correction have been selected and underwent an adductor canal block by one of our trauma anaesthetist that specialises in this procedure. Their outcomes were recorded in their clinical records and patients were contacted by phone to document their experiences. Results. 14 patients with chronic, treatment refractory lower limb pain who were being managed in our orthoplastics clinic following complex, lower limb trauma were identified. Six of those patients had required plastic coverage. Of these 14 patients, all stated their pain completely resolved after the procedure and then returned between 24 hours and 4 weeks after the procedure. Two patients underwent a saphenous nerve diversion after conduction of the blocks, reporting subsequent resolution of their complaints. Conclusions. As a proof of concept, we report that the saphenous nerve underlies chronic pain in patients with complex lower limb injuries. An adductor canal block is an effective diagnostic tool for these patients. Saphenous diversion may offer a permanent solution in patients who respond well to saphenous nerve block. A prospective study is planned to objectively measure pain and quality of life scores after treatment of complex injuries and pre and post adductor canal block

Surgeon-performed periarticular injection and anesthesiologist-performed femoral nerve or adductor canal block with local anesthetic have been used in multimodal pain management for total knee arthroplasty (TKA) patients. Anesthesiologist-performed adductor canal blocks are costly, time consuming, and may be unreliable. We investigated the feasibility of a surgeon-performed saphenous nerve (“adductor-canal”) block from within the knee joint. A retrospective analysis of 94 thigh-knee MRI studies was performed to determine the relationship between the width of the distal femur at the epicondylar axis and the proximal location of the saphenous nerve after its exit from the adductor canal and separation from the superficial femoral artery. After obtaining these data, TKA resections and trial component implantation were performed, using a medial parapatellar approach, in 11 fresh cadaveric lower extremity specimens. Using a blunt tip 1.5cm needle, we injected 10 ml each of two different colored solutions at two different intra-articular medial injection locations, and after 30 minutes, dissected the femoral and saphenous nerve and femoral artery from the hip to the knee to determine the location of the injections. Based upon the MRI analysis, the saphenous nerve was located (and had exited the adductor canal) at a mean of 1.5 times the epicondylar width in females, and mean 1.3 times the epicondylar width in males, proximal to the medial epicondyle. After placement of TKA trial components and injection, the proximal injection site solution bathed the saphenous nerve in 8 of 11 specimens. The proximal blunt needle and solution was adjacent, but did not puncture, the femoral artery and vein in only one specimen. This study suggests that a surgeon-performed injection of the saphenous nerve from within the knee is a feasible procedure. This technique may be a useful alternative to ultrasound guided block. A trial comparing surgeon and anesthesiologist-performed nerve block should be considered to determine the clinical efficacy of this procedure. Our anecdotal use of this intra-articular injection over the past year has been favorable. Newer, extended release anesthetic agents should be investigated with this technique

Introduction. Fast track arthroplasty regimens require preservation of motor power to perform early rehabilitation and ensure early discharge (1). Commonly performed nerve blocks like femoral and Sciatic nerve blocks results in motor weakness thereby interfering with early rehabilitation and may also predispose to patient falls (2, 3). Hence, targeting the terminal branches of the femoral and sciatic nerves around the knee joint under ultrasound is an attractive strategy. The nerve supply of interest for knee analgesia are the terminal branches of the femoral nerve, the genicular branches of the lateral cutaneous nerve of thigh, obturator and sciatic nerves (4). Methods. We modified the performance of the adductor canal block and combined it with US guided posterior pericapsular injection and lateral femoral cutaneous nerve block to provide analgesia around the knee joint. The femoral artery is first traced under the sartorius muscle until the origin of descending geniculate artery and the block is performed proximal to its origin. A needle is inserted in-plane between the Sartorius and rectus femoris above the fascia lata and 5 ml of 0.5% ropivacaine (LA) is injected to block the intermediate cutaneous nerve of thigh. The needle is then redirected to enter the fascia of Sartorius to deliver an additional 5ml of LA to cover the medial cutaneous nerve of thigh following which it is further advanced till the needle tip is seen to lie adjacent to the femoral artery under the Sartorius to perform the adductor canal block with an additional 15–20 ml of LA to cover nerve to vastus medialis, saphenous nerve and posterior division of the obturator nerve (Fig 1). The lateral cutaneous nerve of thigh is optionally blocked with 10 ml of LA near the anterior superior iliac spine between the origin of Sartorius and tensor fascia lata (Fig 2). The terminal branches of sciatic nerve to the knee joint is blocked by depositing 25 ml of local anesthetic solution between the popliteal artery and femur bone at the level of femoral epicondyles (Fig 3). Results. The initial experience of the block performed on 10 patients reveal the median (IQR) block duration is noted to be around 20 (±6.5) hours. The median (IQR) pain scores in the first 24 postoperative hours ranged from 0 (±0.5) to 3 (±2.5) at rest and 1.5 (±3.5) to 5.5 (±1) on movement. All patients were successfully mobilized on the morning of the first postoperative day. Conclusion. Motor sparing from the blocks while providing adequate analgesia can be achieved by selectively targeting the sensory innervation of the knee joint. Future comparative studies are needed to evaluate the performance of the block against other modes of analgesia for knee arthroplasty

Introduction/Aim. The NAVIO robotic-assisted TKA (RA-TKA) application received FDA clearance in May 2017. This semi-active robotic technique aims to improve the accuracy and precision of total knee arthroplasty. The addition of robotic-assisted technology, however, also introduces another potential source of surgery-related complications. This study evaluates the safety profile of NAVIO RA-TKA. Materials and Methods. Beginning in May 2017, the first 250 patients undergoing NAVIO RA-TKA were included in this study. All intra-operative complications were recorded, including: bleeding; neuro-vascular injury; peri-articular soft tissue injury; extensor mechanism complications; and intra-operative fracture. During the first 90 days following surgery, patients were monitored for any post-operative complications, including: superficial and deep surgical site infection; pin-tract infection; pin site fractures; peri-prosthetic fractures; axial or sagittal joint instability; axial mal-alignment; patello-femoral instability; DVT/PE; re-operation or re-admission due to surgical-related complications. Surgical technique and multi-modality pain management protocol was consistent for all patients in the study. A combined anesthetic technique was employed for all cases, including: low-dose spinal, adductor canal block and general anesthetic. Patients were mobilized per our institution's rapid recovery protocol. Results. No patients were lost to follow-up. During the study period, no intra-operative complications were recorded. Specifically, no complications related to the introduction of the high-speed burr associated with the NAVIO RA-TKA were noted. Within the 90-day follow-up period, there was one case of deep infection. One patient sustained a fall resulting in a peri-prosthetic femoral fracture, that occurred remote from the femoral pin tracts. No cases of axial or sagittal joint instability, axial mal-alignment, patello-femoral instability, pin site infections or fractures; or DVT/PE were identified. Four patients underwent manipulation under anesthesia. No other patients required a re-operation or re-admission due to surgical-related complications. Discussion/Conclusions. The initial experience with the NAVIO robotic assisted total knee arthroplasty has demonstrated excellent safety profile. Relative to known risks associated with total knee arthroplasty, no increased risk of peri-operative complications, re-operation or re-admission for surgical related complications was identified with the introduction of the NAVIO RA-TKA

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

Introduction. Regional anesthesia is commonly utilized to minimize postoperative pain, improve function, and allow earlier rehabilitation following Total Knee Arthroplasty (TKA). The adductor canal block (ACB) provides effective analgesia of the anterior knee. However, patients will often experience posterior pain not covered by the ACB requiring supplemental opioid medications. A technique involving infiltration of local anesthetic between the popliteal artery and capsule of knee (IPACK) targets the terminal branches of the sciatic nerve, providing an alternative for controlling posterior knee pain following TKA. Materials and Methods. IRB approval was obtained, a power analysis was performed, and all patients gave informed consent. Eligible patients were those scheduled for an elective unilateral, primary TKA, who were ≥ 18 years old, English speaking, American Society of Anesthesiologists physical status (ASA PS) classification I-III. Exclusion criteria included contraindication to regional anesthesia or peripheral nerve blocks, allergy to local anesthetics, allergy to nonsteroidal anti-inflammatory drugs (NSAIDs), chronic renal insufficiency with GFR < 60, chronic pain not related to the operative joint, chronic (> 3 month) opioid use, pre-existing peripheral neuropathy involving the operative limb, and body mass index (BMI) ≥ 40 kg/m. 2. . Patients were randomized into one of two treatment arms: Continuous ACB with IPACK (IPACK Group) block or Continuous ACB with sham subcutaneous saline injection (No IPACK Group). IPACK Group received single injection of 20 mL 0.25% Ropivacaine. Postoperatively, all patients received a standardized multimodal analgesic regimen. The study followed a double-blinded format. Only the anesthesiologist performing the block was aware of randomization status. Following surgery, a blinded medical assessor recorded cumulative opioid consumption, average and worst pain scores, and gait distance. Results. 72 people were enrolled in the study and three withdrew. There were 35 people in the IPACK group and 34 in the NO IPACK group. There was no difference demographically between the groups. In the Post Anesthesia Care Unit (PACU), the average (P=0.0122) and worst (P=0.0168) pain scores at rest were statistically lower in the IPACK group. There was no difference in the pain scores during physical therapy. (P=0.2080) There was no difference in opioid consumption in the PACU (P=0.7928), at 8 hours (P=0.2867), 16 hours (P=0.2387), 24 hours (P=0.7456), or 30 hours (P=0.8029). There was no difference in pain scores on POD 1 in the AM (P=0.4597) or PM (P=0.6273), nor was there any difference in walking distance (P=0.5197). There was also no difference in length of stay in the PACU (P=0.9426) or hospital (P=0.2141) between the two groups. Discussion/Conclusion. Overall, pain was well controlled between the two groups. The IPACK group had lower pain scores at rest in the PACU, but this may not be clinically significant. The routine use of the IPACK is not supported by the results of this study. There may be use of the IPACK block as a rescue block or in patients whom have contraindications to our standard multimodal treatment regimen, or in patients with chronic pain or opioid dependence

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

Total joint arthroplasty (TJA) has historically been considered primarily an inpatient operation. However, the actual length of stay (LOS) has diminished over time. At our institution the LOS from 1987 to 1990 averaged five to seven days. This decreased to three days from 1993 to 2002 and down to one to two days from 2005 to 2011. With the adaptation of improved anesthesia and pain management protocols, minimally invasive surgery techniques, rapid recovery protocols, and proper patient selection, outpatient (OP) TJA appears to be the next step in maximizing peri-operative efficiency; especially as younger patients are undergoing TJA. Other potential benefits of OP TJR include improved patient care and control, better patient and surgeon satisfaction and a lower overall cost. Over a twenty-four month period (July 2012 to June 2014) we performed 250 primary TJAs (139 hips and 111 knees) and twelve revision TJAs (six hips and six knees). All patients received 400 mg of celecoxib pre-operation and 200 mg/day for ten days. In addition to general anesthesia, hips received a short-acting spinal and knees received an adductor canal block. Tranexamic acid (IV or topical) and a pericapsular injectable cocktail of liposomal bupivacaine was routinely used. There was one deep infection (0.4%) and one readmission for pain control (0.4%). Two cases of deep vein thrombosis were diagnosed (0.8%). Patient education, home health care utilization, and proper patient selection are key factors to keep hospitalization rates, emergency room visits, and re-admission rates to a minimum

Over the past fifteen years, the average length of stay for total knee arthroplasty (TKA) has gradually decreased from several days to overnight. The most logical and safest next step is outpatient arthroplasty. Through the era of so-called minimally invasive surgery, perhaps the most intriguing advancements are not related to the surgery itself, but instead the areas of rapid recovery techniques and perioperative protocols. Rapid recovery techniques and perioperative protocols have been refined to allow for same-day discharge with improved outcomes. As mentioned, the single most important outcome from the minimally invasive movement has been the multi-modal approach to pain management of patients undergoing arthroplasty. Along with blood loss management, using tranexamic acid and hypotensive anesthetic techniques, this multi-modal program is the most important variable in reducing or avoiding side-effects. In any arthroplasty procedure, side-effects that need to be addressed include the negative effects of narcotics and blood loss. Anesthetic techniques, utilizing local nerve blocks, such as the adductor canal block and sciatic blocks for knee arthroplasty augment intraoperative anesthesia and provide postoperative pain relief and quicker mobilization. Additionally, pericapsular injection with a cocktail of local anesthetic helps significantly with pain relief and recovery reducing the amount of oral narcotic utilised in the early postoperative period. Many have utilised liposomal bupivacaine in these cocktails to successfully increase the period of pain relief. The use of multi-modal perioperative protocols can help avoid narcotics and helps avoid the side-effects of nausea. We also utilise an aggressive prophylactic antiemetic program with dexamethasone, ondansetron and a scopolamine patch. Patients without any significant cardiovascular history are given celecoxib preoperatively, which is continued for approximately two weeks postoperatively. Immediately postoperative, acetaminophen and additional dexamethasone are administered intravenously. The multi-modal protocols to address fear, risk, and side-effects will increase the eligibility for outpatient surgery and decrease the need for overnight hospitalization. By focusing on the patient and avoiding over-treatment, outpatient arthroplasty is quickly becoming the standard of care for total hip replacement in the same way other procedures transitioned from hospital in-patient surgeries to ambulatory procedures