A comparison of knee joint motion patterns between men and women in selected athletic tasks
Introduction
Anterior cruciate ligament (ACL) disruption is a commonly seen knee injury. It was estimated that the incidence of ACL disruption was one in 3000 people in the general population [1] with over 70% of all ACL injuries occurred in sport activities [2], [3], [4]. Paulos [5] reported that nearly 50,000 primary ACL surgeries were performed in 1982 in the United States alone. The majority of ACL injuries are non-contact in nature, that is, there is no direct physical contact to the athlete when an injury occurs [6], [7], [8].
Women have a higher incidence than men for non-contact ACL injuries in sport activities. Recent injury reports from National Collegiate Athletic Association indicate that female collegiate soccer and basketball players were three and four times more likely to have non-contact ACL injuries than their male counterparts [9]. Other studies report the non-contact ACL injury rate for female athletes as high as eight times of that for male athletes [5], [10], [11], [12], [13], [14], [15], [16].
Several intrinsic and extrinsic factors have been proposed as contributors to the increased incidence of non-contact ACL ruptures among female athletes [9]. Among these intrinsic and extrinsic factors, altered neuromuscular control strategies and movement patterns are likely to contribute to the increased incidence of non-contact ACL injuries for female athletes. A recent study [8] showed non-contact ACL injuries frequently occurred with the knee at small flexion angle accompanied by a knee valgus motion during running, cutting, and jumping tasks in soccer and basketball. Studies have shown that the contraction of the quadriceps muscle group applies an anterior shear force on the tibia through the patella tendon [17], [18]. This shear force may lead to an ACL injury when the knee flexion angle is less than 30° and the hamstring muscle group does not apply sufficient posterior shear force [17], [18].
The purpose of this study was to compare three-dimensional (3-D) knee joint motions and electromyographic (EMG) activities of the quadriceps and hamstring muscle groups between male and female recreational athletes in running, cross-cutting, and side-cutting. We hypothesize:
- 1.
Female athletes tend to have smaller knee flexion angles than male athletes during the support phases in athletic tasks such as running, side-cutting, and cross-cutting;
- 2.
Female and male athletes tend to have different knee valgus–varus angles during the stance phase in these athletic tasks;
- 3.
Female athletes tend to have higher quadriceps muscle activation than male athletes during these athletic tasks; and
- 4.
Female athletes tend to have lower hamstring muscle activation than male athletes during these athletic tasks.
Section snippets
Subjects
Twenty healthy recreational athletes (11 males and 9 females), with no known history of any knee pathological conditions were randomly recruited from Duke University campus. A recreational athlete was defined as a person who plays basketball, soccer, or volleyball less than or equal to three times per week but does not follow a professionally designed training regimen. The mean age, height, and body mass were 24.5 (SD, 2.5) yr, 1.80 (SD, 0.05) m, and 78.1 (SD, 7.3) kg, respectively, for male
Results
The mean approach run speeds were 5.21 (SD, 0.45) m/s, 5.18 (SD, 0.38) m/s, and 5.15 (SD, 0.46) m/s for male subjects in running, side-cutting, and cross-cutting, respectively, and 5.11 (SD, 0.51) m/s, 5.01 (SD, 0.44) m/s, and 4.96 (SD, 0.41) m/s for female subjects. The mean takeoff speeds were 5.23 (SD, 0.41) m/s, 4.68 (SD, 0.42) m/s, and 4.41 (SD, 0.44) m/s for male subjects in running, side-cutting, and cross-cutting, respectively, and 5.17 (SD, 0.55) m/s, 4.46 (SD, 0.42) m/s, and 4.25 (SD,
Discussion
The results of this study support our hypotheses indicating that female and male athletes on average have different knee motion patterns in selected athletic tasks, specifically, female athletes have decreased knee flexion angle, increased knee valgus angle, increased quadriceps muscle activation, and decreased hamstring muscle activation. These differences in knee motion patterns between female and male subjects may be attributed to differences between female and male athletes in (a) motor
References (31)
- et al.
Arthroscopic strain gauge measurement of the normal anterior cruciate ligament
Arthroscopy
(1990) Justification of triaxial goniometer for the measurement of joint rotation
J. Biomech.
(1980)- et al.
Experimental determination of forces transmitted through the patello-femoral joint
J. Biomech.
(1988) - et al.
The orientation of the distal part of the quadriceps femoris muscle as a function of the knee flexion–extension angle
J. Biomech.
(1985) - et al.
The incidence of knee ligament injuries in the general population
Am. J. Knee Surg.
(1991) - Feagin JA. Isolated anterior cruciate injury. The crucial ligaments. New York: Churchill Livingstone, 1988. p....
- Johnson RJ. Prevention of cruiate ligament injuries. The crucial ligaments. New York: Churchill Livingstone, 1988. p....
- et al.
Biology and biomechanics of the anterior cruciate ligament
Clin. Sports Med.
(1993) - Paulos LE. Why failures occur symposium: Revision ACL surgery. American Orthopaedic Society for Sports Medicine...
- et al.
The symptomatic ACL-deficient knee
J. Bone Joint Surg.
(1983)