Perioperative nerve injury after total knee arthroplasty: regional anesthesia risk during a 20-year cohort study.
BACKGROUND
Perioperative nerve injury (PNI) is one of the most debilitating complications after total knee arthroplasty (TKA). Although regional anesthesia (RA) techniques reduce pain and improve functional outcomes after TKA, they may also contribute to PNI. The objective of this study was to test the hypothesis that PNI risk differs among patients according to RA use during TKA.


METHODS
All patients aged at least 18 yr who underwent elective TKA from January 1988 to July 2007 were retrospectively identified. The primary outcome variable was the presence of a new PNI documented within 3 months of the procedural date. Age, sex, body mass index, type of procedure, tourniquet time, type of anesthesia, and use of peripheral nerve blockade were evaluated as potential risk factors for PNI using multivariable logistic regression.


RESULTS
Ninety-seven cases of PNI were identified among 12,329 patients. Overall incidence of PNI was 0.79% (95% CI, 0.64-0.96%). PNI was not associated with peripheral nerve blockade (odds ratio [OR], 0.97) or type of anesthesia (OR, 1.10 [neuraxial vs. general]; OR, 1.82 [combined vs. general]). Risk for PNI decreased with age (OR, 0.68 [per decade]; P < 0.001) but increased with tourniquet time (OR, 1.28 [per 30-min increase]; P = 0.003) and bilateral procedures (OR, 2.51; P < 0.001). Patients with PNI who underwent peripheral nerve blockade were less likely to have complete neurologic recovery (OR, 0.37; P = 0.03).


CONCLUSIONS
Risk for PNI after TKA was unchanged by the use of RA techniques. This finding supports the notion that the known benefits of RA for patients undergoing TKA can be achieved without increasing risk of neurologic injury. However, in rare situations when PNI occurs, complete recovery may be less likely if it develops after peripheral nerve blockade.
Department of Anesthesiology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA.
Adam K
AK
Jacob
Carlos B
CB
Mantilla
Hans P
HP
Sviggum
Darrell R
DR
Schroeder
Mark W
MW
Pagnano
James R
JR
Hebl
D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D000765:Anesthesia, Conduction / Q000009:adverse effects* / Q000379:methods; D019645:Arthroplasty, Replacement, Knee; D015992:Body Mass Index; D015984:Causality; D015331:Cohort Studies; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008875:Middle Aged; D016017:Odds Ratio; D010523:Peripheral Nervous System Diseases / Q000453:epidemiology* / Q000209:etiology; D011183:Postoperative Complications / Q000453:epidemiology / Q000209:etiology; D012042:Registries; D012189:Retrospective Studies; D012307:Risk Factors; D017678:Sex Distribution; D013997:Time Factors; D014111:Tourniquets; D016896:Treatment Outcome; D055815:Young Adult