Adductor canal block versus femoral nerve block for total knee arthroplasty: a prospective, randomized, controlled trial.

BACKGROUND: This prospective double-blinded, randomized controlled trial compared adductor canal block (ACB) with femoral nerve block (FNB) in patients undergoing total knee arthroplasty. The authors hypothesized that ACB, compared with FNB, would exhibit less quadriceps weakness and demonstrate noninferior pain score and opioid consumption at 6 to 8 h postanesthesia. METHODS: Patients received an ACB or FNB as a component of a multimodal analgesic. Quadriceps strength, pain score, and opioid consumption were assessed on both legs preoperatively and at 6 to 8, 24, and 48 h postanesthesia administration. In a joint hypothesis test, noninferiority was first evaluated on the primary outcomes of strength, pain score, and opioid consumption at 6 to 8 h; superiority on each outcome at 6 to 8 h was then assessed only if noninferiority was established. RESULTS: Forty-six patients received ACB; 47 patients received FNB. At 6 to 8 h postanesthesia, ACB patients had significantly higher median dynamometer readings versus FNB patients (median [interquartile range], 6.1 kgf [3.5, 10.9] (ACB) vs. 0 kgf [0.0, 3.9] (FNB); P < 0.0001), but was not inferior to FNB with regard to Numeric Rating Scale pain scores (1.0 [0.0, 3.5] ACB vs. 0.0 [0.0, 1.0] FNB; P = 0.019), or to opioid consumption (32.2 [22.4, 47.5] ACB vs. 26.6 [19.6, 49.0]; P = 0.0115). At 24 and 48 h postanesthesia, there was no significant statistical difference in dynamometer results, pain scores, or opioid use between the two groups. CONCLUSION: At 6 to 8 h postanesthesia, the ACB, compared with the FNB, exhibited early relative sparing of quadriceps strength and was not inferior in both providing analgesia or opioid intake.

Burden incurred by patients and their caregivers after outpatient surgery: a prospective observational study.

INTRODUCTION: The burden of patients and their caregivers after outpatient surgery has not been fully examined. The number of outpatient surgeries has dramatically increased in the last several years, particularly in the orthopaedic sector. Patients undergoing outpatient orthopaedic procedures may be expected to have more postdischarge pain than those undergoing nonorthopaedic outpatient procedures. In light of this, assessment of patient and caregiver expectations and actual burden after discharge is of importance. QUESTIONS/PURPOSES: We assessed the impact of outpatient surgery on recovery of patients and their caregivers in the postoperative period by determining (1) expected versus actual time to resume daily activities, including work; (2) expected versus actual recovery at 7 and 30 days postoperatively; and (3) the number of caregivers that felt emotional or physical disturbances from caring for outpatients. METHODS: Forty-four adult patients undergoing outpatient surgical procedures and their primary caregivers were enrolled in this prospective survey study, of which 30% were orthopaedic patients. Surveys assessing postoperative recovery were given to patients at six time points, on Postoperative Days 0 to 3, 7, and 30. Surveys assessing the burden of informal caregiving were given to each patient's primary caregiver at four time points, on Postoperative Days 1 to 3 and 7. The enrollment rate was 79% (44 enrolled of 56 approached) and the survey response rate was 100% for patients and 93% (41 of 44) for caregivers. RESULTS: We found that 16 of 44 patients (36%) needed more time than originally anticipated to resume their daily activities and three of 29 patients (10%) needed more time off from work than originally anticipated. Patients were approximately 66% and 88% fully recovered 7 and 30 days after surgery, respectively. The primary caregivers noted disturbances in emotional (nine of 43, 21%) and physical (17 of 43, 40%) aspects of their daily lives while providing care for patients. Our surveyed patients were from multiple surgical services; however, our results may be generalized to an orthopaedic population, although they may underestimate actual results for this population given their generally higher pain scores. CONCLUSIONS: Patients may take longer to recover from outpatient surgery than previously recognized. As increased pain and prolonged recovery may be associated with increased caregiver burden, these data are of particular significance to the outpatient orthopaedic surgical population. Informal caregiving after outpatient surgery may be an unrecognized physical and psychologic burden and may have a significant societal impact. LEVEL OF EVIDENCE: Level II, prognostic study. See Instructions for Authors for a complete description of levels of evidence.

Alpha 3 beta 1 integrin promotes keratinocyte cell survival through activation of a MEK/ERK signaling pathway.

Inadequate or inappropriate adhesion of epithelial cells to extracellular matrix leads to a form of apoptosis known as anoikis. During various tissue remodelling events, such as wound healing or carcinoma invasion, changes in the physical properties, and/or composition of the extracellular matrix, can lead to anoikis of epithelial cells that lack appropriate receptor-matrix interactions. Laminin-5 is the major ligand for keratinocyte adhesion in the epidermis, and it also promotes keratinocyte survival in vivo and in vitro. Integrins alpha 3 beta 1 and alpha 6 beta 4 are the major receptors for laminin-5; however, specific roles for these integrins in keratinocyte survival have not been determined. In the current study, we exploited keratinocyte cell lines derived from wild-type or alpha 3 integrin knockout mice to reveal a critical role for alpha 3 beta 1 in protecting keratinocytes from apoptosis upon serum withdrawal. We show that alpha 3 beta 1-mediated adhesion to laminin-5 extracellular matrix inhibits proteolytic activation of caspase-3 and TUNEL-staining, both hallmarks of apoptosis. We also show that alpha 3 beta1-mediated adhesion activates focal adhesion kinase (FAK) and extracellular signal-regulated kinase (ERK), and that inhibition of either FAK or ERK signaling leads to apoptosis of keratinocytes attached to laminin-5. alpha 6 beta 4-mediated adhesion to laminin-5 only partially protects cells from apoptosis in the absence of alpha 3 beta 1, and alpha 6 beta 4 is not necessary for cell survival in the presence of alpha 3 beta 1. These results suggest that alpha 3 beta 1 is necessary and sufficient for maximal keratinocyte survival on laminin-5. We propose a model to address the potential importance of alpha 3 beta 1-mediated survival for migrating keratinocytes at the leading edge of a cutaneous wound.