The Effect of Phases of the Menstrual Cycle on Frontal PlaneKnee Kinematics During Landing
Jacalyn J Robert-McComb1, C RogerJames2, Jennifer Merkle Ford1, Reid Norman2, Greg Dedrick2
1Texas Tech University,
Lubbock, Texas, USA
2Texas Tech University Health Science Center, Lubbock, Texas, USA
*Corresponding author: Jacalyn J Robert-McComb, Departmentof Health, Exercise, and Sport Sciences, Texas Tech University, Lubbock, TX 79409-3011, USA. Tel: +18068346306; +18067981073; +18067421688; Email: jacalyn.Mccomb@ttu.edu
Received Date: 19 August, 2017; Accepted Date: 07 September,
2017; Published Date: 14 September, 2017
Citation: Robert-McComb JJ, James CR, Ford JM, Norman R, Dedrick G (2017) The Effect of Phases of the Menstrual Cycle on Frontal Plane Knee Kinematics During Landing. Yoga Practice Phys Ther: YPPT-133. DOI: 10.29011/YPTR-133. 000033
1. Abstract
Knee valgus, a known Anterior Cruciate Ligament (ACL) injury risk factor, is subject to hormonal changes during the menstrual cycle. Therefore, the purposeof this study was to analyze 2D frontal plane knee kinematics during drop-jump landing across phases of the human menstrual cycle (days 1-3;11-13;21-23). Twenty-seven (18-25 years) females with normal menstrual cycles initially met inclusion criteria for study participation. Twenty two-females were used for data analysis.The protocol consisted of drop-jumps from a 50cm platform while the participant’s frontal plane movement was recorded using a single digital video camera (60 Hz). The initial time period for data collection was counterbalanced across days of the menstrual cycle and randomized. The procedures were identical for all repeated testing.Two separate one-way repeated measures ANOVAs were used to analyze landing patterns. Alpha was set at .05. There was a significant difference for valgus knee angle among days 1-3, 11-13, and 21-24 of the menstrual cycle, F(2, 42) = 3.92, p = .037. Post-hoc tests revealed a significant difference for valgus knee angle between days 1-3 and days 11-14, t(21) = 2.733, p = .012.No other significant differences were found. The largest magnitude of valgus knee angleoccurred during the late follicular phase (days 11-14) of the menstrual cycle, when there was a large spike in estradiol.
2. Keywords: ACL Injury; Human Menstrual Cycle; Landing Pattern; Valgus Knee Angle
Figure 1: Changes in Hormonal Levels during a Normal Menstrual
Cycle.
Figure 2: Retroreflective Markers on Participants.
Figure 3: Mean Knee Distance.
Figure 4: Mean Valgus Knee Angle.
Variable |
M ± SD |
Range |
Age |
20.18 ± 1.82 |
18-24 |
Height (cm) |
165.97± 5.42 |
158.8-180.3 |
Weight (kg) |
64.22 ± 14.79 |
49.9-120 |
Activity level scale |
5.23 ± 1.27 |
04-Aug |
Age Began Menses |
13.27 ± 1.08 |
Nov-15 |
Number of days of cycle |
5.23 ± 1.27 |
03-Aug |
Number of days between cycles |
28.27±1.45 |
26-31 |
Leg Length (cm) |
85.41±3.27 |
82-94 |
Tibial Length (cm) |
38.60±1.94 |
34.5-43 |
Craig’s test (degrees) |
10.19±0.89 |
9.25-13.50 |
Quadriceps angle (degrees) |
16.14±1.13 |
15-20 |
Hematocrit (%) |
41.59±2.52 |
39-50 |
Table 1: Descriptive Characteristics of Subjects (N=22).
|
Early Follicular |
Late Follicular |
Mid-Luteal |
Estradiol (pg/ml) |
61±22.15 |
159±27.95 |
132±19.30 |
(16.07-95.6) |
(39.21-563.49) |
(50.01-530.52) |
|
Progesterone (ng/ml) |
0.65±0.09 |
1.20±0.41 |
11.10±1.54 |
(0.16-1.93) |
(0.19-4.06) |
(1.07-24.51) |
|
Testosterone (ng/ml) |
0.26±0.02 |
0.34±0.03 |
0.36±0.04 |
(0.15-0.58) |
(0.18-0.84) |
(0.17-0.91) |
|
Note: Values are M ± SD with the range in parentheses |
Table 2: Hormone Levels by Cycle Phase (N=22).
|
Early Follicular |
Late Follicular |
Mid-Luteal |
Knee Distance (cm) |
32.92±4.55 |
32.32 ±4.37 |
33.03±4.61 |
(26.43-45.85) |
(24.77-45.60) |
(27.21-45.86) |
|
Knee Angle (degrees) |
−7.83±5.74 |
−9.70±7.26 |
−7.53±6.44 |
(−.47- −25.92) |
(−3.22- −31.91) |
(1.23- −31.07) |
|
Note: Values are M ± SD with the range in parentheses |
Table 3: Knee Distance and Knee Angle by Cycle Phase (N=22).