بررسی تغییرات فرایند طرح حرکتی به پاسخ های وضعیتی عضلات تنه در افراد سالم و بیماران با سابقه کمردرد

The changes that occur in all of the motor unit recruitment following the central and peripheral lesions of motor nerves can be effective on individual's disability. Following the low back pain (L.B.P) with any known cause, the effective role of muscles in providing postural or dynamic stability will be reduced. Today in rehabilitation of these patients, except of medical treatment for reduction of pain, a great attention is given to assess the motor control and its efficiency in order to prevent reappearance of the disease symptoms. The aim of this research is to determine the amount of changes in motor planning at motor control level in order to provide an appropriate setting for movement of lumbar spine following postural responses and peripheral stimulation.Materials and Methods: Ten healthy women (24.3+2.32 year) and five women with L.B.P (27.34+4.67 years) without any structural disorder of lumbar spine have participated in this study. The test stages included flexion and extension in sagital plan with/ without external hearing stimulation in the 30 degree of flexion and 10 degree of extension, with 5 repetition. By measuring the amount of individual's reactions and computation of range of motion (R.O.M), the velocity, torque and delay time for showing any reaction prior to reaching stimulation point and its post time as well as comparing them with each other in both groups and also comparing these two groups.Results: There are a significant differences between R.O.M changes, velocity and torque in similar times before and after hearing stimulation in both types of movement (P<0.05). In such a way the said values before hearing the external stimulation was much greater than after hearing the external stimulations and appearance of postural responses (P<0.05). Also in comparing with the conditions that external stimulation and postural response imposing was loosed, the time of appearance the postural response has shown a meaningful reduction (P<0.05). The group consisted of patients with L.B.P in compare with normal group, during the period that the movement were without any external stimulation , has shown no significant difference, while in stages with external stimulation and occurrence of postural responses, the R.O.M , time , velocity and torque have shown a significant difference (P<0.05). In healthy cases the percentage of functional performance reduction following external stimulation was more than the patients (P<0.05). This shows that the patients with history of L.B.P will have problems in setting up motor planning or in feedworward process.