Table 4.

Adjusted analysis for 2-year Knee Injury and Osteoarthritis Outcome Score between the isolated anterior cruciate ligament reconstruction and concomitant medial collateral ligament injury groups

Two-year KOOS domain	Isolated ACL# (n = 6420)	ACL + non-surgically treated MCL (n = 236)			ACL + MCL suture repair (n = 21)			ACL + MCL reconstruction (n = 30)
	Adjusted means* (95% CI)	Adjusted means* (95% CI)	Difference between groups adjusted means (95% CI)	Adjusted p value*	Adjusted means* (95% CI)	Difference between groups adjusted means (95% CI)	Adjusted p value*	Adjusted means* (95% CI)	Difference between groups adjusted means (95% CI)	Adjusted p value*
KOOS4	70.7 (70.2–71.2)	67.0 (64.4–69.5)	3.7 (1.2; 6.3)	0.005	60.9 (52.5–69.4)	9.8 (1.3; 18.2)	0.024	62.8 (55.7–69.8)	7.9 (0.8; 15.0)	0.028
Symptoms	76.6 (76.1–77.0)	73.5 (71.1–75.8)	3.1 (0.7; 5.5)	0.011	66.4 (58.5–74.3)	10.2 (2.3; 18.0)	0.012	68.6 (62.0–75.2)	8.0 (1.3; 14.6)	0.018
Pain	83.4 (83.0-83.8)	81.3 (79.1–83.4)	2.1 (− 0.1; 4.3)	n.s	78.2 (71.0–85.3)	5.2 (− 1.9; 12.4)	n.s	80.1 (74.2–86.1)	3.3 (− 2.7; 9.2)	n.s
ADL	90.3 (89.9–90.7)	89.6 (87.7–91.4)	0.7 (− 1.1; 2.6)	n.s	90.1 (83.9–96.2)	0.2 (− 5.9; 6.4)	n.s	88.4 (83.2–93.6)	1.9 (− 3.3; 7.1)	n.s
Sports and recreation	63.5 (62.9–64.2)	58.1 (54.6–61.6)	5.4 (1.8; 9.0)	0.003	50.4 (38.7–62.2)	13.1 (1.4; 24.9)	0.028	49.5 (39.7–59.3)	14.1 (4.3; 23.9)	0.005
QoL	59.3 (58.7–59.9)	55.0 (51.9–58.0)	4.3 (1.2; 7.4)	0.007	48.7 (38.5–59.0)	10.5 (0.2; 20.8)	0.045	52.9 (44.3–61.4)	6.4 (− 2.2; 15.0)	n.s

ACL anterior cruciate ligament, ADL activities of daily living, CI confidence interval, MCL medial collateral ligament, n number of patients, n.s non-significant, QoL quality of life

^#The isolated ACL group was used as a reference group for all comparisons between groups

*Adjusting for age at surgery, patient sex and cartilage injury using analysis of covariance (ANCOVA)