title: Does decreased meniscal thickness affect surgical outcomes after medial meniscectomy?
abstract: BACKGROUND
  There have been no clinical studies regarding the effect of decreased meniscal thickness on outcomes after meniscectomy.
  
  
  OBJECTIVE
  To examine the postoperative outcomes of partial meniscectomy with or without horizontal resection compared with the outcomes of subtotal meniscectomy and to evaluate the influence of decreased thickness of the medial meniscus on outcomes after partial meniscectomy.
  
  
  METHODS
  Cohort study; Level of evidence, 3.
  
  
  METHODS
  A total of 312 patients who underwent medial meniscectomy were retrospectively reviewed. Patients were divided into 3 groups: group A (n = 84) included patients with partial meniscectomy with vertical resection, group B (n = 140) consisted of those with partial meniscectomy with horizontal resection, and group C (n = 88) included those with subtotal meniscectomy. Clinical function was evaluated by use of the Lysholm knee scoring scale, International Knee Documentation Committee (IKDC) subjective knee evaluation form, and Tapper and Hoover grading system. Radiologic evaluation was performed with the IKDC radiographic assessment scale as well as with measurements of the medial compartment height at the tibiofemoral joint. Preoperative values and postoperative values measured 5 years after operation were assessed.
  
  
  RESULTS
  Functional outcomes in group C were inferior to those in groups A and B according to the Lysholm knee score (mean ± SD for group A = 96.1 ± 4.7, group B = 94.9 ± 5.2, group C = 84.8 ± 11.4; P < .001), IKDC subjective score (group A = 92.1 ± 6.5, group B = 91.3 ± 8.8, group C = 81 ± 11.4; P < .001), and Tapper and Hoover grading system (P = .003). There was no significant difference in scores between groups A and B. With regard to radiologic evaluation, the IKDC radiographic grade for group C was worse than the grades for groups A and B (P < .001); there was no significant difference between groups A and B. However, the postoperative joint space on the affected side was higher for group A (4.7 ± 0.6 mm) than for groups B (4.3 ± 0.5 mm; P < .001) and C (3.7 ± 0.8 mm; P < .001). The joint space was higher in group B than in group C (P < .001).
  
  
  CONCLUSIONS
  Despite joint space narrowing, decreases in meniscal thickness after partial meniscectomy for horizontal tear had no additional adverse effect on 5-year functional and radiographic outcomes compared with conventional partial meniscectomy preserving whole meniscal thickness. In treating horizontal tears of the meniscus, partial meniscectomy with complete resection of the unstable leaf was an effective method in a 5-year follow-up study.
authors.affiliation: Arthroscopy and Joint Research Institute, Department of Orthopaedic Surgery, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Sung-Jae
authors.initials: SJ
authors.lastname: Kim
authors.affiliation: Department of Orthopaedic Surgery, Gwangmyung Sungae Hospital, Gyeonggi, Korea.
authors.forename: Su-Keon
authors.initials: SK
authors.lastname: Lee
authors.affiliation: Arthroscopy and Joint Research Institute, Department of Orthopaedic Surgery, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Sung-Hwan
authors.initials: SH
authors.lastname: Kim
authors.affiliation: Department of Orthopaedic Surgery, Seoul Wooridul Hospital, Seoul, Korea.
authors.forename: Jae-Hoon
authors.initials: JH
authors.lastname: Jeong
authors.affiliation: Arthroscopy and Joint Research Institute, Department of Orthopaedic Surgery, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Hak-Soo
authors.initials: HS
authors.lastname: Kim
authors.affiliation: Arthroscopy and Joint Research Institute, Department of Orthopaedic Surgery, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Se-Won
authors.initials: SW
authors.lastname: Lee
authors.affiliation: Arthroscopy and Joint Research Institute, Department of Orthopaedic Surgery, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Jae-Hoo
authors.initials: JH
authors.lastname: Lee
authors.affiliation: Arthroscopy and Joint Research Institute, Department of Orthopaedic Surgery, Yonsei University College of Medicine, Seoul, Korea jmin1103@naver.com.
authors.forename: Min
authors.initials: M
authors.lastname: Jung
mesh_terms: D000293:Adolescent; D000328:Adult; D001182:Arthroscopy / Q000379:methods*; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007719:Knee Joint / Q000473:pathology / Q000601:surgery*; D008297:Male; D008592:Menisci, Tibial / Q000473:pathology / Q000601:surgery*; D008875:Middle Aged; D011184:Postoperative Period; D012189:Retrospective Studies; D012421:Rupture / Q000601:surgery; D000070600:Tibial Meniscus Injuries; D055815:Young Adult
keywords: arthroscopy; horizontal tear; meniscectomy; meniscus