title: Is patellar denervation necessary in total knee arthroplasty without patellar resurfacing?
abstract: OBJECTIVE
  To conduct a meta-analysis with randomized controlled trials (RCTs) published in full text to determine the effectiveness of patellar denervation (PD) in primary total knee arthroplasty (TKA).
  
  
  METHODS
  Literature search was performed in PubMed, Embase, Web of Science and Cochrane Library for information from the earliest date of data collection to February 2015. RCTs comparing the benefits and risks of PD with those of no patellar denervation (NPD) in primary TKAs were included. Statistical heterogeneity was quantitatively evaluated by X(2) test with the significance set P < 0.10 or I (2) > 50 %.
  
  
  RESULTS
  Six RCTs consisting of 751 patients were included. The incidences of AKP in PD group and NPD group were 38.3 % (90/235) and 46.3 % (107/231), respectively. Meta-analysis showed significant prevention effect of PD on the incidence of AKP (OR 0.65; 95 % CI 0.42, 1.00; P = 0.05) without significant heterogeneity (I (2) = 44 %, P = 0.15). Our results also indicated that PD was significantly associated with better American Knee Society knee (WMD = 2.50; 95 % CI 0.34, 4.67; P = 0.02) and functional scores (WMD = 4.07; 95 % CI 1.34, 6.80; P = 0.0003) and range of motion (ROM) (WMD = 4.27; 95 % CI 1.95, 6.60; P = 0.0003) compared with NPD. However, there was no significant difference between the two groups no matter in Oxford knee score, patellar score or visual analogue scale at any other time. Complications and revisions did not differ significantly between the two groups.
  
  
  CONCLUSIONS
  This meta-analysis showed that PD in TKAs without patellar resurfacing, compared with NPD, could prevent the incidence of post-operative AKP and improve clinical outcome in KSS and post-operative ROM. Based on the above results, PD was a safe procedure with no significant complications and revision or re-operations.
  
  
  METHODS
  Therapeutic study, Level II.
authors.affiliation: Department of Orthopedic Center, Affiliated Hospital of Logistics University of the Chinese People's Armed Police Forces, Tianjin, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Zhang
authors.affiliation: Department of Orthopedic, The Chinese People's Armed Police Forces in Fujian Province, Longyan, China.
authors.forename: Hao
authors.initials: H
authors.lastname: Liu
authors.affiliation: Department of Orthopedic Center, Affiliated Hospital of Logistics University of the Chinese People's Armed Police Forces, Tianjin, China.
authors.forename: Wen-Shan
authors.initials: WS
authors.lastname: Yan
authors.affiliation: Department of Orthopedic Center, Affiliated Hospital of Logistics University of the Chinese People's Armed Police Forces, Tianjin, China. 15banzhangpeng@sina.com.
authors.forename: Wen-Liang
authors.initials: WL
authors.lastname: Wang
mesh_terms: D018771:Arthralgia / Q000453:epidemiology*; D019645:Arthroplasty, Replacement, Knee / Q000379:methods*; D003714:Denervation / Q000379:methods*; D006801:Humans; D015994:Incidence; D007719:Knee Joint / Q000601:surgery; D020370:Osteoarthritis, Knee / Q000601:surgery*; D010147:Pain Measurement; D010149:Postoperative Pain / Q000453:epidemiology*; D010329:Patella / Q000294:innervation* / Q000601:surgery; D016032:Randomized Controlled Trials as Topic; D016059:Range of Motion, Articular; D012086:Reoperation; D016896:Treatment Outcome; D064232:Visual Analog Scale
keywords: Anterior knee pain; Meta-analysis; Patellar denervation; Total knee arthroplasty