This prospective study was conducted at Rajaii educational exercise training university in Tehran from September 2006 to January 2007. Our population included 66 nonprofessional athletes (educational exercise students) who were enrolled in track- and- field as a main course. Twenty-one male and 45 female (age 20 ± 1.5 years, BMI 21 ± 2 Kg/m2 and height 1.68 ± .9 m) were studied. Subjects with a history of congenital deformity, surgery and traumatic injuries to either lower extremity in the previous 6 months were excluded. A session was held at university to distribute consent forms and give an overview of the research.
The measures were taken in the first 3 weeks of the semester. At the time of measurement, each subject signed consent form and the examiner completed a demographic data sheet that included name, sex, age, and number of competitive running years. The initial sample consisted of 68 runners, 21 men and 47 women, which provided 136 limbs. Two of runners were eliminated because of injury during the course. Data pertaining to past history of leg pain, injury or fracture, number of hours in physical activity per week, type of physical activity and associated diseases were collected in the questionnaire.
Static lower extremity measurements including intercondylar interval of femur, intermalleolar distance, Quadriceps angle, hip internal rotation angle, hip external rotation angle, tibiofemoral angle, tibial alignment, rear foot alignment or calcaneal (Achilles) angle, navicular drop test and length of lower limb were measured in every lower limb.
All angle measurements were taken using one goniometer and recorded. The measurements were taken 2 times and an average was calculated. On all subjects, the anatomical landmarks were drawn by a nontoxic ballpoint pen and erased after first set of measurements with an alcohol swab. Then several photos were taken from knee and ankle of limbs by a digital ixus 70 Canon camera (with 7.1 mega pixel resolutions). All photos were taken bare foot, in standing position, in specific distance and with constant angle in the same location [9, 10], then all photographs were analyzed in Photoshop software (version 7.0) for determination of angles in degrees.
All measurements and physical examinations had been performed by one physician (sport medicine specialist). All subjects were trained during educational track- and- field course and they were running, jumping, marching and circuit training 14 hours per week for 17 weeks. The location of training and surface of field was the same for all subjects and the shoes of all subjects were checked for appropriateness. All shoes were common runner type and no one used insole. After the training period (17 weeks), all subjects were examined for clinical sign and symptoms of MTSS. The diagnostic criteria of MTSS included:
Pain history: pain was induced by exercise and lasted for a few hours or days after exercise, located on the posteromedial border of the tibia, no history of paresthesia or other neurovascular symptoms indicative of other causes of leg pain
Location: Over an area minimum of 5 cm, along the posteromedial border of the tibia.
Palpation: Palpation of the posteromedial border of the tibia produced pain that was diffuse in nature and confined to the posteriomedial border of the tibia [2, 12].
Ethics
A session was held at university to inform the subjects. At the time of measurement, each subject signed a consent form. All photos were taken only from Lower extremity. All data and photos were confidential and the results were reported as general overview.
Measurement protocol
Lower extremity measures were chosen from common standard clinical measures of foot, knee and leg posture. Height was measured by stadiometer, to 0.5 cm, and weight by electronic scale, to 0.1 kg [4, 10, 13, 14].
Hip range of motion
The hip and knee were flexed a 90° in the sitting position; rotated internally and externally to a firm end feel and the angles relative to the initial position were measured in degrees.
Intercondylar and intermalleolar interval
With the subject standing upright; with closed feet held parallel to each other, the intervals were measured using a gauge (accuracy 0.1 mm) for estimation of Knee varus, valgus and ankle eversion and inversion.
Q angles
The Q angle was measured with the subject's knee and hip in extension, and the quadriceps muscle relaxed. First, the center axis of a long-arm goniometer over the center of the patella was placed. Then, the proximal tibia was palpated and the lower goniometer arm along the patellar tendon to the tibial tubercle aligned. The upper arm of the goniometer was pointed directly at the anterior superior iliac spine (ASIS). The angle measured by the goniometer was the Q angle. The angle was marked by a ballpoint pen, after that the photos were taken and in Photoshop software were analyzed and the angles were determined and compared [13, 15].
Tibiofemoral angle
With the subject standing upright; the center axis of a long-arm goniometer was placed over the center of the patella. The upper arm of the goniometer was pointed on the bisection of femur and lower arm along the bisection of tibia and measuring the degree, estimation of femoral and tibial alignment was possible. Then landmarks were drawn by marker, photos were taken and in Photoshop software were analyzed and the angles were determined and compared [16].
Rear foot alignment (Achilles or calcaneal angle)
With the subject lying prone, one leg extended and the other leg externally rotated and bent at the knee at approximately 90°, the calcaneus and one third of extended lower leg were marked for rearfoot measurements. A line was drawn bisecting the lower one third of the extended leg and another line was drawn bisecting the calcaneus. Inversion and eversion of the calcaneal position was determined in degrees with a goniometer [17, 18].
Tibial alignment
Each leg was measured in standing position. The medial and lateral aspects of the tibia were palpated, and then the medial-lateral bisection was determined. Tibial alignment was measured with a goniometer marked in degree [10, 16]. The photos were taken and in Photoshop software was used for the analysis and the angles were determined and compared. Tibial alignment and Q angle were evaluated according to results taken from Photoshop analysis. Other measures were taken from physical examination.
Navicular drop test
Navicular drop was measured in standing position based on the description by Sell et al [19] and Picciano et al [20]. The navicular tuberosity was palpated at its greatest prominence and marked with a nontoxic marker. In bilateral standing, the subject was placed in subtalar joint neutral. The distance between the floor and the navicular mark was measured in millimeters with goniometer. The subject then stood in unilateral stance, and the examiner again measured the distance (mm) between the floor and the navicular mark. The difference between the navicular height in bilateral and unilateral standing was recorded as the navicular drop [17].
Leg Length discrepancy
Each leg length was measured using a tape measure (nearest 0.5 cm), in the supine position, from the anterior superior iliac spine to the most prominent aspect of the medial malleolus [10, 21].
Intratest reliability
A pilot study was done to determine the intratester reliability of measurements (kappa = 0.75). Using the procedures described above, 20 limbs from 15 subjects were measured 3 times during 1 week. To eliminate subject identification, random assignment of subject order was performed by computer and measurers were blinded to the subjects.
Statistical analysis
Descriptive statistics including mean, st. error of mean, median and std. deviation were calculated for runners' characteristics.
Data were typed and analyzed in software of SPSS version 15. For comparing continuous normally distributed data, T-test was performed; and in the case of determining the association between two categorical data, Chi-square test was run.
The Odds ratio & 95% CI were conducted for precision, determination of the effect size and clinical degree of significance.