Objective To compare the analgesia effect and clinical rehabilitation between continuous adductor canal block (ACB) and single shot ACB in total knee arthroplasty (TKA)． Methods Between October 2016 and February 2017, 60 patients with severe knee osteoarthritis undergoing primary unilateral TKA were prospectively recruited in the study. All the patients were randomly allocated into 2 groups and received ultrasound-guided continuous ACB (group A, n=30) or single shot ACB (group B, n=30), respectively. There was no significant difference in gender, age, body mass index, nationality, American Society of Anesthesiology (ASA) grading, and preoperative knee range of motion and quadriceps strength between 2 groups (P>0.05). After operation, the tourniquet time, postoperative drainage volume, hospitalization time, and adverse events in 2 groups were recorded. Visual analogue scale (VAS) scores at rest and during activity, the quadriceps strength, the knee range of motion, and the time of 90° knee flexion in 2 groups were also recorded and compared. Results There was no significant difference in tourniquet time, postoperative drainage volume, and incidence of adverse events between 2 groups (P>0.05). But the hospitalization time was significant shorter in group A than in group B (P<0.05). VAS scores at rest and during activity were lower in group A than in group B, with significant differences in VAS score at rest after 12 hours and in VAS score during activity after 8 hours between 2 groups (P<0.05). The quadriceps strength was higher in group A than in group B, with significant difference at 24, 48, and 72 hours (P<0.05). The knee range of motion was significantly better in group A than in group B at 24, 48, 72 hours and on discharge (P<0.05). The time of 90° knee flexion was significantly shorter in group A than in group B (t=–2.951, P=0.016). There were 4 patients in group A and 7 patients in group B requiring meperidine hydrochloride (50 mg/time) within 24 hours, and 3 patients in group A and 7 patients in group B at 24 to 48 hours, and 1 patient in group A and 3 patients in group B at 48 to 72 hours. Effusion in the catheter site occurred in 2 cases of group A, but no catheter extrusion occurred. Conclusion Continuous ACB is superior in analgesia both at rest and during activity and opioid consumption compared with single shot ACB after TKA. And the quadriceps strength could be reserved better in continuous ACB group, which can perform benefits in early rehabilitation.
Objective To summarize the research progress of the analgesic effect of adductor canal block (ACB) applied to knee arthroplasty, in order to find the ACB mode that can obtain better effectiveness. MethodsThe research progress of the analgesic effect of ACB after knee arthroplasty was reviewed by widely consulting the related literature on ACB at home and abroad in recent years. Results In recent years, multimodal analgesia has become the mainstay of postoperative pain management after knee arthroplasty. Among these, ACB replaces the once “gold standard” femoral nerve block (FNB) by offering comparable and effective analgesia with better preservation of quadriceps function. It is generally safe and efficient to use 0.2% ropivacaine ACB with initial loading doses of 15-30 mL and continual loading doses of less than 8 mL/hour to give analgesia comparable to FNB with minimal impact on lower extremity muscular strength. However, the risk of patient falls must still be taken into consideration by medical staff. Adjuvants like dexmedetomidine and dexamethasone used in ACB can increase the analgesic duration and postoperative analgesic impact. As a perineural adjunct for ACB, 1 µg/kg dexmedetomidine may strike a balance between safety and analgesic efficacy. Conclusion ACB is a safe and effective analgesia method after knee arthroplasty. The adductor canal anatomy, the optimum blocking strategy and blocking site of ACB are all hotly debated and still require additional study due to the significant variety of the nerve structures in adductor canal.
Objective To compare the early analgesic effects and the impact on knee joint function recovery after unicompartmental knee arthroplasty (UKA) between single adductor canal block (SACB) and continuous adductor canal block (CACB) combined with local infiltration anesthesia (LIA) using a prospective study. Methods The patients with knee osteoarthritis admitted between April 2022 and December 2023 were enrolled as a subject. Among them, 60 patients met the selection criteria and were enrolled in the study. They were randomly assigned to the SACB group or CACB group in a ratio of 1:1 using a random number table method. There was no significant difference between the two groups (P>0.05) in terms of age, gender, height, body mass, body mass index, affected side, and preoperative resting visual analogue scale (VAS) score and active VAS score, Oxford knee score (OKS), and American Hospital of Special Surgery (HSS) score. All patients received multimodal analgesia management using LIA combined with SACB or CACB. The operation time, pain related indicators (resting and activity VAS scores, number and timing of breakthrough pain, opioid consumption), joint function related indicators (quadriceps muscle strength, knee range of motion, OKS score, and HSS score), as well as postoperative block complications and adverse events were recorded and compared between the two groups. Results There was no significant difference in the operation time between the two groups (P<0.05). All patients in the two groups were followed up with a follow-up time of (9.70±4.93) months in the SACB group and (12.23±5.05) months in the CACB group, and the difference was not significant (P>0.05). The CACB group had a significant lower resting VAS score at 24 hours after operation compared to the SACB group (P<0.05). There was no significant difference in resting and active VAS scores between the two groups at other time points (P>0.05). The CACB group had a significantly lower incidence of breakthrough pain compared to the SACB group [9 cases (30.00%) vs. 17 cases (56.67%); P<0.05). However, there was no significant difference in the timing of breakthrough pain occurrence and opioid consumption between the two groups (P>0.05). Four cases in the SACB group and 7 cases in the CACB group experienced adverse events, with no significant difference in the incidence of adverse events between the two groups (P>0.05). The CACB group had significantly better knee joint mobility than the SACB group at 1 and 2 days after operation (P<0.05). There was no significant difference between the two groups in knee joint mobility on 0 day after operation and quadriceps muscle strength and OKS and HSS scores at different time points (P>0.05). Conclusion In UKA, the analgesic effects and knee joint function recovery are similar when compared between LIA combined with SACB and LIA combined with CACB. However, SACB is simpler to perform and can avoid adverse events such as catheter displacement and dislocation. Therefore, SACB may be a better choice.
Objective To compare the effect of sciatic nerve block (SNB) combined with continuted femoral nerve block (FNB) or continuted adductor canal block (ACB) on pain and motor function after total knee arthroplasty (TKA). Methods A total of 60 patients with TKA-treated osteoarthritis of the knee who met the selection criteria were enrolled between November 2020 and February 2021 and randomised allocated into the study group (SNB combined with continuted ACB) and the control group (SNB combined with continuted FNB), with 30 cases in each group. There was no significant difference in gender, age, body mass, height, body mass index, preoperative Hospital for Special Surgery (HSS) score, femoral tibial angle, and medial proximal tibial angle between the two groups (P>0.05). The operation time, the initial time to the ground, the initial walking distance, and the postoperative hospital stay were recorded. At 2, 4, 6, 12, 24, and 48 hours after operation, the numerical rating scale (NRS) score was used to evaluate the rest pain around the knee joint, the quadriceps femoris muscle strength was evaluated by the freehand muscle strength method, and the knee flexion and extension angles were measured. Results There was no significant difference in the operation time and initial walking distance between the two groups (P>0.05); the initial time to the ground and postoperative hospital stay of the study group were significantly shorter than those of the control group (P<0.05). Except for the 48-hour postoperative NRS score of the study group, which was significantly lower than that of the control group (P<0.05), there was no significant difference in the NRS scores between the two groups at the remaining time points (P>0.05). The quadriceps femoris muscle strength from 4 to 24 hours postoperatively and the knee extension angle from 2 to 6 hours postoperatively of the study group were significantly better than those of the control group (P<0.05); the differences in the quadriceps femoris muscle strength and knee extension and flexion angles between the two groups at the remaining time points were not significant (P>0.05). Conclusion SNB combined with either continuted ACB or continuted FNB can effectively relieve pain in patients after TKA, and compared with combined continuted FNB, combined continuted ACB has less effect on quadriceps femoris muscle strength, and patients have better recovery of knee flexion and extension mobility.