The effect of C1-C2 manipulation on hamstring flexibility

Although the muscle inhibition technique and myofascial relaxation technique applied to the suboccipital muscles have been shown to be effective in increasing hamstring flexibility, there are no studies on the effect of C1-C2 manipulation on hamstring muscle flexibility. It is thought that the same effect will occur with the manipulation technique applied to the C1-C2 vertebrae. The aim of this study is to investigate the acute effect of C1-C2 manipulation on hamstring muscle flexibility. Individuals that compliance with the inclusion criteria were divided to two groups: 25 individuals (X±SD; age= 27.48±3.56 years; BMI= 24.81±2.97 kg/m2) with hamstring muscle flexibility loss and C1-C2 dysfunction and 25 individuals (X±SD; age= 27.88±4.33 years; BMI= 24.47±2.58 kg/m2) with hamstring muscle flexibilty loss and no C1-C2 dysfunction. Active knee extension test, passive straight leg raise test and sit-reach test, which are used to evaluate the shortness of hamstring muscles, were evaluated in both groups before and after the intervention. The intervention was performed in the position where the individuals were lying on their back and their eyes were closed. Age, gender and body mass index distributions of the groups were homogeneous (p>0.05). When the changes before and after the intervention were compared within-group, a statistically significant difference was found (p<0.001), and when compared between groups, no statistically significant difference was found (p>0.05). In our study, the increase in hamstring muscle flexibility as a result of C1-C2 manipulation supports the idea that suboccipital muscles and hamstring muscles are connected with a single fascia and that spinal manipulation has mechanisms of action such as biomechanical, muscular reflexogenic and muscle tone. In conclusion, C1-C2 manipulation can be offered as a treatment option in individuals with hamstring muscle flexibility loss and can be used as a supportive approach to other physiotherapy-rehabilitation methods.