Table 3

Difference in 2-year postoperative KOOS in patients with below and above median preoperative scores after adjustment for preoperative KOOS

  Low preoperative scoreHigh preoperative score
All patientsNβ (95% CI)pValueNβ (95% CI)p Value
β (95% CI)p ValueNARNKLRNARNKLR
Pain2.9 (0.0 to 5.8)0.0531210593.4 (−5.9 to 12.6)0.4727212962.9 (0.4 to 5.3)0.023
Symptoms8.5 (4.9 to 12.2)<0.0013312706.2 (−0.1 to 12.5)0.0535111239.7 (5.4 to 13.9)<0.001
ADL2.3 (−0.1 to 4.8)0.0651612714.5 (−2.0 to 11.0)0.1736810851.5 (−0.7 to 3.7)0.191
Sports7.6 (2.4 to 12.7)0.00414125320.6 (7.0 to 34.1)0.0037010885.1 (0.2 to 10.0)0.042
QoL5.5 (0.8 to 10.2)0.02227147712.3 (3.6 to 21.0)0.006578942.1 (−2.9 to 7.2)0.409
  • β Represents the difference in KOOS associated with the NAR cohort versus the NKLR after adjustment for preoperative KOOS, sex, age, time from injury to surgery, meniscus injury at ACLR and cartilage injury at ACLR. Positive values indicate higher scores in the NAR cohort.

  • Low/high preoperative scores are defined as scores below/above the median preoperative scores (cut-off points: Pain: 77.78, Symptoms: 75, ADL: 91.18, Sports: 45, QoL: 37.5).

  • ACLR, anterior cruciate ligament reconstruction; ADL, activities of daily living; KOOS, Knee Injury and Osteoarthritis Outcome Score; NAR, Norwegian Research Center for Active Rehabilitation; NKLR, Norwegian National Knee Ligament Registry; QoL, quality of life.