Kashmir is regarded as the state of farmers. Approximately 74% of the population is involved directly or indirectly with farming. Meniscus injuries are common worldwide and are on the rise due to the increased involvement of people in sports activities. While the incidence of meniscus injuries is well known in athletes, its incidence in the non-athletic female population is high in this part of world owing to cultural and traditional habits.
5.1. Mechanism of Injury
Menisci can be torn during innocuous activities, such as walking or squatting. The traumatic action is most often a twisting movement at the knee while the leg is bent. This is the typical posture our females adopt during rice winnowing in a squatting position. They squat (hyperflexion of knee), hold the winnower with both hands full of rice, and then throw the rice up into the air, allowing the air to separate the husk from the rice during its fall. In this process, the weight of the rice and the force used to throw it into the air generates lot of stress to the knees. While winnowing, these female workers often twist their knees. Patients first present with recurring pain, locking and effusions of the knee when they start seeking medical advice. The medial meniscus is torn more often than the lateral meniscus, since the medial meniscus is less mobile. Sometimes, when going from a squatting position to standing, the menisci gets caught between the femoral and tibial condyles, developing a tear in the medial meniscus.
In this study, the mean BMI of patients was higher in the meniscus injury group where squatting or no definite trauma was cited as the cause of injury. The right knee was involved more (n = 35) than the left knee (n = 15). We presume this is due to traditional habits. The age group of patients had little observable effect on the mechanism as most were in a single range; however, the mean age group among those with sprains was lower. The age group of the female population used for this study when compared to other studies is lower. We presume that most of our females are involved in traditional and cultural habits that predispose them to knee stress, whereas in other studies, either athletic, degenerative, or generalized trauma had all been studied. Also, women in this part of world are less exposed to athletic activities because of religious restrictions. The RTA is also less frequent and women are usually not using two-wheelers for transportation. A high percentage (42%) of people in our study experienced a meniscus injury due to winnowing, as women farmers suffer from multiple musculoskeletal problems that are caused by overuse or misuse of muscles that significantly impair their activities for daily living (
8). The knee injuries in non-athletic household females is primarily due to extreme postures such as kneeling and squatting for long hours at home and on the farm ( 4). Other postures, like bending and twisting while squatting also affect the knees. The adult meniscus is avascular in the inner two-thirds ( 9). Meniscal injury may be the most common knee problem that women farmers are bound to be exposed to as a result of extreme postures ( 10), lifting loads, and long hours of winnowing rice at fields or at home. According to the United States National Library of Medicine ( 11), isolated medial meniscus tears occur more frequently than any other tear. Traumatic lesions of the menisci are commonly produced via rotation while the flexed knee moves toward an extended position. The most common location for injury is the posterior horn of the meniscus, where longitudinal tears are the most common type of injury. A meniscus is usually torn due to a rotational force incurred while the joint is partially flexed, which is the posture these female farmers adapt while squatting and winnowing. During vigorous internal rotation of the femur on the tibia with the knee in a squatting posture while throwing rice up and down in the winnower, the femur tends to force the medial meniscus posteriorly and towards the center of the joint. If the peripheral attachment of the menisci are torn or stretched, the posterior part of the meniscus is forced toward the center of the joint and is caught between the femur and tibia. This results in a longitudinal tear when the knee is suddenly extended.
The prevalence of meniscus tears is the same in both knees. In a few different studies, the BMI of a person was shown to have a greater effect on the frequency of meniscus tears. This is because having a higher BMI results in more weight on the joints, which can cause misalignment of the knee that, in turn, causes more weight on the muscles and results in an easier tear. The same was observed in our study. In 2008, the U.S. Department of Health and Human Services reported a combined total of 2,295 discharges with a principal diagnosis being a tear in the lateral cartilage/meniscus (836.0), a tear in the medial cartilage/meniscus (836.1), and a tear in the cartilage/meniscus (836.2). Females comprised a total of 53.49% of discharges, while males made up 45.72%. Individuals between the ages of 45 - 68 comprised approximately 31.73% of discharges, followed by the 65 - 84 age group with 28.82% of discharges (
12). In 1948, Fairbank ( 13) described radiographic changes following total meniscectomies.
Suthar et al. (
8) noted that 56.67% of female farmers had pain in their thighs, and a large segment (63.33%) reported pain in their calf muscles due to various household and farm chores.
Preventing these injuries is a big challenge for policy makers, as it is difficult to convince uninformed individuals about preventative measures and teach them alternative ways to winnow. However, a mass campaign targeting farmers could be held to educate them. The proverb, "When a king sits on his throne to judge, he winnows out all evil with his eyes," rings true, but is practically impossible to follow. Winnowing rice with the wind’s help, or using winnowing fans on farms are both possible alternatives. At home, women should be advised to sit on a support placed under the buttocks and keep their knees extended while doing so. Also, they should be discouraged from keeping their right knee fully flexed and upright when holding the winnowing basket and while removing the husk. Thorough examination of the knee joint is of utmost importance and a high index of suspicion is required while dealing with the farmer population, as the actual prevalence of such a condition may be high.
It is an unfortunate reality that working rural women suffer from multiple musculoskeletal problems that significantly impair their daily life activities. In the home and farm, women perform tasks while sitting, standing, squatting, bending, twisting, and engaging in awkward postures during prolonged working hours and with inadequate rest. These facts are associated with the occurrence of serious musculoskeletal disorders. We have found that winnowing in a squatting position for repeated and extended periods has been a major cause of chronic knee pain in our female population. The symptom complex comprises a typical working non-athletic female with chronic, low-grade knee pain and a history of recurrent knee swellings and locking following an acute injury to the knee from winnowing rice in a squatting position. Further studies with proper randomization should be conducted in the countries where farming is prominent in order to draw definitive conclusions.