Table 1

Baseline characteristics prior to the index ACLR

VariableTotal
(n=22 928)
Only one ACLR (n=21 748)One revision ACLR
(n=1144)
Multiple revision ACLR
(n=36)
P valueTest between groups p value
Only one ACLR vs one revision ACLROnly one ACLR vs more than one revision ACLROne revision ACLR vs more than one revision ACLR
Age at the time of surgery (years)28.7±10.6
26 (16–74)
29.1±10.7
26 (16–74)
22.9±7.6
20 (16–56)
22.6±7.2
20.5 (16–44)
<0.00010.00200.00200.86
Sex (male)12 055 (52.6)11 429 (52.6)604 (52.8)22 (61.1)0.58
BMI (kg/m2)24.7±3.3
24.2 (15.1–49.8)
24.7±3.3
24.2 (15.1–49.8)
24.5±3.1
24.2 (17.6; 37.6)
24.7±3.2
23.5 (19.6–34)
0.42
Time from index ACLR to first revision (years)3.25±2.49
2.39 (0.02–14.44)
3.27±2.51
2.44 (0.02–14.44)
2.34±1.63
1.75 (0.77–6.54)
0.032
Time from index ACLR to last revision (years)3.35±2.57
2.53 (0–14.44)
3.26±2.51
2.43 (0–14.44)
6.07±2.99
5.75 (0.97–13.33)
<0.0001
Time from injury to index surgery (months)20.4±36.6
8.3 (0–551)
20.9±37.3
8.5 (0–551)
11.3±18.6
5.7 (0–242.7)
16.6±38.2
5 (1–167.3)
<0.00010.00200.630.14
ACL graft (yes)
 Patellar tendon autograft1276 (5.6)1214 (5.6)62 (5.5)0
 Semitendinosus autograft20 898 (92.2)19 821 (92.2)1041 (92.5)36 (100.0)
 Quadriceps tendon autograft354 (1.6)338 (1.6)16 (1.4)0
 Allograft82 (0.4)77 (0.4)5 (0.4)0
 Direct suture/synthetic/other44 (0.2)42 (0.2)2 (0.2)00.90
Meniscus injury (yes)
 Lateral meniscus5557 (24.2)5239 (24.1)313 (27.4)5 (13.9)0.0150.0140.210.097
 Medial meniscus6026 (26.3)5783 (26.6)236 (20.6)7 (19.4)<0.0001<0.00010.441.00
Cartilage injury (yes)
 Lateral femoral condyle1257 (5.5)1208 (5.6)48 (4.2)1 (2.8)0.110.0510.801.00
 Medial femoral condyle4216 (18.4)4050 (18.6)160 (14.0)6 (16.7)0.0004<0.00010.970.79
 Lateral patella687 (3.0)669 (3.1)18 (1.6)00.00840.00240.651.00
 Medial patella1190 (5.2)1149 (5.3)41 (3.6)00.0150.0100.280.55
 Lateral tibial plateau1461 (6.4)1412 (6.5)49 (4.3)00.00340.00220.180.42
 Medial tibial plateau1217 (5.3)1181 (5.4)34 (3.0)2 (5.6)0.00140.00011.000.60
 Trochlea721 (3.1)699 (3.2)22 (1.9)00.0280.0130.621.00
Collateral ligament injury (yes)
 MCL963 (4.2)913 (4.2)47 (4.1)3 (8.3)0.46
 LCL232 (1.0)225 (1.0)7 (0.6)00.32
 PLC injury (yes)51 (0.2)48 (0.2)3 (0.3)00.92
Activity at the time of injury (yes)
 Alpine/skiing3798 (16.6)3693 (17.0)103 (9.0)2 (5.6)
 Pivoting sport14 565 (63.6)13 638 (62.8)900 (78.7)27 (75.0)
 Non-pivoting sport991 (4.3)954 (4.4)36 (3.1)1 (2.8)
 Other physical activity986 (4.3)953 (4.4)33 (2.9)0
 Traffic-related409 (1.8)396 (1.8)11 (1.0)2 (5.6)
 Other2135 (9.3)2071 (9.5)60 (5.2)4 (11.1)<0.0001<0.00010.140.063
Tibial fixation (yes)
 Interference screw14 545 (63.4)13 802 (63.5)719 (62.8)24 (66.7)
 Intratunnel fixation473 (2.1)457 (2.1)16 (1.4)0
 Suture post5053 (22.0)4780 (22.0)265 (23.2)8 (22.2)
 Retroscrew280 (1.2)253 (1.2)25 (2.2)2 (5.6)
 Fixed suspensory fixation22 (0.1)21 (0.1)1 (0.1)0
 Adjustable suspensory fixation2555 (11.1)2435 (11.2)118 (10.3)2 (5.6)0.0220.0190.170.68
Femoral fixation (yes)
 Fixed suspensory fixation9644 (42.1)9099 (41.8)531 (46.4)14 (38.9)
 Intratunnel fixation3817 (16.6)3646 (16.8)164 (14.3)7 (19.4)
 Interference screw3219 (14.0)3014 (13.9)194 (17.0)11 (30.6)
 Adjustable suspensory fixation6248 (27.3)5989 (27.5)255 (22.3)4 (11.1)<0.0001<0.00010.0120.080
 Follow-up time after most recent surgery (years)9.19±4.07
9.2 (1.21–17.14)
9.32±4.06
9.34 (2.2–17.14)
6.73±3.51
6.44 (1.21–17.05)
5.62±2.69
4.99 (2.35–14.04)
<0.00010.00200.00200.066
  • Values are given as n (%) and mean±SD or median (minimum–maximum) for categorical and continuous as well as ordinal variables, respectively. The sums may vary because of missing values. The variables with missing values, n (%) of the total sample were BMI 7900 (34.2), time from injury to surgery 618 (2.7) and activity at the time of injury 44 (0.2).

  • Pivoting sport (American football/rugby, basketball, dancing, floorball, gymnastics, handball, ice hockey/bandy, martial arts, racket sports, soccer, volleyball, wrestling); non-pivoting sport (cross-country skiing, cycling, horseback riding, motocross/endure, skateboarding, snowboarding and surfing/wakeboarding); alpine/skiing; other physical activity (other recreational sport, exercise, trampoline); traffic related; and other (other outdoor activity and work). Tibial fixation devices were divided into six different subcategories: (1) interference screw (metal screw, metal screw with backup staple fixation, resorbable screw, resorbable screw with backup post fixation, metal screw with backup osteosuture, intrafix); (2) intratunnel fixation (rigidfix); (3) suture post (AO screw, suture washer); (4) retroscrew; (5) fixed suspensory fixation (retrobutton); (6) adjustable suspensory fixation (tightrope). Femoral fixation devices were also divided into four different subcategories: (1) fixed suspensory fixation (endobutton, retrobutton, ezloc); (2) intratunnel fixation (rigidfix, transfix); (3) interference screw (metal screw); (4) adjustable suspensory fixation (toggleloc, ultrabutton).

  • signficant p value are in bold.

  • ACL, anterior cruciate ligament; ACLR, anterior cruciate ligament reconstruction; BMI, body mass index; LCL, lateral collateral ligament; LM, lateral meniscus; MCL, medial collateral ligament; PLC, posterior lateral corner.