title: Anterior cruciate ligament reconstruction reduces bone mineral areal mass.
abstract: OBJECTIVE
  The aim of this study was to prospectively follow bone mineral areal mass (BMA) changes in the calcaneii, hips, and lumbar spine after anterior cruciate ligament (ACL) reconstruction using hamstring tendon autografts.
  
  
  METHODS
  Patients with a unilateral ACL injury scheduled for reconstruction were included in the study. The BMA mass was measured in both calcaneii, the hips, and the lumbar spine using the dual-energy x-ray absorptiometry (DEXA) technique. Quality of life was estimated using the EQ-5D questionnaire, and activity was measured using the Tegner activity score. The patients were assessed before surgery and after 6, 18, 36, and 60 months.
  
  
  RESULTS
  Forty-eight patients (21 female and 27 male patients), median age 31 years (17 to 64 years), participated in the study for 5 years. After 5 years, the female patients had lost 9.5% (P < .001) and 10.1% (P < .001) of their BMA in the calcaneus on the operated and nonoperated sides, respectively. Correspondingly, the male patients had lost 6.5% (P = .004) and 8.5% (P < .001) on the operated and nonoperated sides, respectively. In the hips, the female patients had lost 4.0% (P < .001) and 2.7% (P < .001) on the operated and the nonoperated sides, respectively. Among the male patients, the BMA loss was 3.4% (P = .002) and 4.8% (P < .001) in the hips on the operated and the nonoperated sides, respectively. The EQ-5D index was a mean (standard deviation [SD]) of 0.72 (0.23) before surgery and 0.86 (0.17) (P < .001) after 5 years. The preinjury Tegner activity level was a median (range) 7.5 (1 to 10). The preoperative Tegner activity level was 2.5 (0 to 9) and increased to 4 (1 to 9) (P = .002) after 5 years.
  
  
  CONCLUSIONS
  Both female and male patients had a significant decrease in BMA in both calcaneii and both hips during the 5-year study period compared with a reference population of Swedish healthy women and men. The patients increased their Tegner activity level and improved their EQ-5D index during the 5-year follow-up period.
  
  
  METHODS
  Level II, prognostic prospective study.
authors.affiliation: Department of Orthopaedics, NU-Hospital Organization, Trollhättan/Uddevalla, and Sahlgrenska Academy, University of Gothenburg, Sweden. Electronic address: sven.stener@vgregion.se.
authors.forename: Sven
authors.initials: S
authors.lastname: Stener
authors.forename: Jüri
authors.initials: J
authors.lastname: Kartus
authors.forename: Lars
authors.initials: L
authors.lastname: Ejerhed
mesh_terms: D015502:Absorptiometry, Photon; D000293:Adolescent; D000328:Adult; D016118:Anterior Cruciate Ligament / Q000601:surgery*; D000070598:Anterior Cruciate Ligament Injuries; D059549:Anterior Cruciate Ligament Reconstruction / Q000009:adverse effects*; D015519:Bone Density; D002111:Calcaneus / Q000000981:diagnostic imaging; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006615:Hip / Q000000981:diagnostic imaging; D006801:Humans; D007718:Knee Injuries / Q000601:surgery; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D010024:Osteoporosis / Q000000981:diagnostic imaging* / Q000209:etiology*; D011446:Prospective Studies; D011788:Quality of Life; D019651:Plastic Surgery Procedures; D013710:Tendons / Q000637:transplantation; D055815:Young Adult