title: Does circumpatellar electrocautery improve the outcome after total knee replacement?: a prospective, randomised, blinded controlled trial.
abstract: The incidence of anterior knee pain following   total knee replacement (TKR) is reported to be as high as 49%. The source   of the pain is poorly understood but the soft tissues around the   patella have been implicated. In theory circumferential electrocautery denervates the patella   thereby reducing efferent pain signals. However, there is mixed   evidence that this practice translates into improved outcomes. We aimed to investigate the clinical effect of intra-operative   circumpatellar electrocautery in patients undergoing TKR using the   LCS mobile bearing or Kinemax fixed bearing TKR. A total of 200   patients were randomised to receive either circumpatellar electrocautery   (diathermy) or not (control). Patients were assessed by visual analogue   scale (VAS) for anterior knee pain and Oxford knee score (OKS) pre-operatively   and three months, six months and one year post-operatively. Patients   and assessors were blinded. There were 91 patients in the diathermy group and 94 in the control.   The mean VAS improvement at one year was 3.9 in both groups (control;   -10 to 6, diathermy; -9 to 8,    p < 0.001 in both cases, paired, two-tailed t-test). There was   no significant difference in VAS between the groups at any other   time. The mean OKS improvement was 17.7 points (0 to 34) in the   intervention group and 16.6 (0 to 42) points in the control (p =   0.36). There was no significant difference between the two groups   in OKS at any other time. We found no relevant effect of patellar electrocautery on either   VAS anterior knee pain or OKS for patients undergoing LCS and Kinemax   TKR.
authors.affiliation: Raigmore Hospital, Department of Orthopaedics, Inverness IV2 3UJ, UK. santoshbaliga@doctors.org.uk
authors.forename: S
authors.initials: S
authors.lastname: Baliga
authors.forename: C J
authors.initials: CJ
authors.lastname: McNair
authors.forename: K J
authors.initials: KJ
authors.lastname: Barnett
authors.forename: J
authors.initials: J
authors.lastname: MacLeod
authors.forename: R W
authors.initials: RW
authors.lastname: Humphry
authors.forename: D
authors.initials: D
authors.lastname: Finlayson
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects / Q000379:methods*; D004311:Double-Blind Method; D004564:Electrocoagulation / Q000379:methods*; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000601:surgery*; D010147:Pain Measurement; D010149:Postoperative Pain / Q000175:diagnosis / Q000209:etiology / Q000517:prevention & control*; D011446:Prospective Studies; D016896:Treatment Outcome