Surface Mapping of Motor Points in Biceps Brachii Muscle

OBJECTIVE: To localize the site of motor points within human biceps brachii muscles through surface mapping using electrophysiological method. METHOD: We recorded the compound muscle action potentials of each lattice of the biceps brachii in 40 healthy subjects. Standardized reference lines were made as the following: 1) a horizontal reference line (elbow crease) and 2) a vertical reference line connecting coracoid process and mid-point of the horizontal reference line. The Compound muscle action potentials were mapped in reference to the standardized reference lines. The locations of motor points were mapped to the skin surface, in the ratio to the length of the vertical and the half of the horizontal reference lines. RESULTS: The motor point of the short head of biceps was located at 69.0+/-4.9% distal and 19.1+/-9.5% medial to the mid-point of horizontal reference line. The location of the motor point of the long head of the biceps was 67.3+/-4.3% distal and 21.4+/-8.7% lateral. The motor point of the short head of the biceps was located more medially and distally in the male subjects compared to that in the female (p<0.05). CONCLUSION: This study showed electrophysiological motor points of the biceps brachii muscles through surface mapping. This data might improve the clinical efficacy and the feasibility of motor point targeting, when injecting botulinum neurotoxin in biceps brachii.

Surface Mapping of Motor Points in Biceps Brachii Muscle

OBJECTIVE: To localize the site of motor points within human biceps brachii muscles through surface mapping using electrophysiological method. METHOD: We recorded the compound muscle action potentials of each lattice of the biceps brachii in 40 healthy subjects. Standardized reference lines were made as the following: 1) a horizontal reference line (elbow crease) and 2) a vertical reference line connecting coracoid process and mid-point of the horizontal reference line. The Compound muscle action potentials were mapped in reference to the standardized reference lines. The locations of motor points were mapped to the skin surface, in the ratio to the length of the vertical and the half of the horizontal reference lines. RESULTS: The motor point of the short head of biceps was located at 69.0+/-4.9% distal and 19.1+/-9.5% medial to the mid-point of horizontal reference line. The location of the motor point of the long head of the biceps was 67.3+/-4.3% distal and 21.4+/-8.7% lateral. The motor point of the short head of the biceps was located more medially and distally in the male subjects compared to that in the female (p<0.05). CONCLUSION: This study showed electrophysiological motor points of the biceps brachii muscles through surface mapping. This data might improve the clinical efficacy and the feasibility of motor point targeting, when injecting botulinum neurotoxin in biceps brachii.

The Effect of Motor Point Block with Alcohol on Hip Adductor Muscles in Spastic Cerebral Palsy

OBJECTIVE: To investigate the effectiveness of motor point blocking using 70% alcohol for the treatment of spasticity in patients with cerebral palsy. METHOD: 16 patients with spastic cerebral palsy were injected at both hip adductor muscles with 70% alcohol. The severity of spasticity was assessed with the modified Ashworth scale (MAS) of adductor muscles, and the passive range of motion (PROM) of hip abduction. MAS and PROM were measured before, immediately after, and 1 and 3 months after the motor point block. Satisfaction of caregivers was also checked 3 months after the procedure. RESULTS: The MAS prior to the motor point block and at 3 months after the procedure were 4.44+/-0.62 and 3.63+/-1.16. The PROM before motor point block and at 3 months after the procedure were 21.81+/-14.14d egrees and 32.81+/-12.37 egrees. 11 out of 16 (68.8%) caregivers reported high satisfaction. CONCLUSION: Motor point block with 70% alcohol to the hip adductor muscles could be a safe and cost-effective procedure for relieving the localized spasticity of hip adductor muscles in spastic cerebral palsy.

Treatment of Torsion Dystonia with Motor Point Block Using Phenol : A case report

Dystonia is an abnormal movement characterized by sustained muscle contractions, frequently causing twisting and repetitive movements or abnormal postures. Torsion dystonia is characterized by torsion spasms of muscle contraction, which distorts the limbs and trunk into dystonic postures. We present a case of a patient with torsion dystonia who was recalcitrant to oral medication or even surgical operations. This patient was treated with motor point block using 5% phenol solution. Using electromyographical guidance, phenol was injected into the paraspinal and upper extremity muscles, respectively. He showed reduction of dystonia and improvement of functional abilities. Motor point block using phenol can be considered as a tool of the management for patients with torsion dystonia. MDVAQ@yumc.yonsei.ac.kr

Anatomical Locations of the Motor Points of the Triceps Surae Muscles

OBJECTIVE: To identify the range of the precise locations of the motor points of triceps surae muscles in relation to bony landmarks. METHOD: Eight limbs of four male cadavers were dissected. The number and location of the motor points from the tibial nerve to each head of the triceps surae muscle were identified related to the bony landmarks. Bony landmarks were medial and lateral epicondyles of the femur, and medial and lateral malleolli of the tibia. The length of the lower leg was defined as the distance from the intercondylar line of the femur to the intermalleolar line of the tibia. The locations of the motor points were expressed as the vertical distance from the intercondylar line, which was normalized to the length of the lower leg. RESULTS: The most proximal motor points of the medial gastrocnemius, lateral gastrocnemius, and soleus were located in 9.6+/-3.5%, 12.0+/-3.4% and 20.5+/-3.9% of the lower leg below the intercondylar line of the femur. The most distal points were in 37.5+/-5.5%, 37.9+/-2.3% and 46.7+/-3.6%. CONCLUSION: The identification of the locations of motor points related to the bony landmarks would increase the ease and accuracy of the motor point blocks to the triceps surae muscles.

Follow-up Study of Motor Point Block by Phenol in Spastic Cerebral Palsy

OBJECTIVE: The purposes of this study are to find out the long-term effect of motor point block using phenol on spasticity and gait pattern of spastic cerebral palsy children and to examine contributing factors for success of phenol block in functional implication of cerebral palsy. METHOD: We injected 5% phenol into muscles of 35 cases with spastic cerebral palsy under the electromyographic monitoring. Pre, immediate post, and follow-up evaluations for type and severity, grade of spasticity, range of motion, and gait patterns by locomotion rating scale (LRS) were analyzed. RESULTS: The degree of spasticity was reduced dramatically by block, but this effect returned back to the level of pre-block state on follow-up evaluation. There was much improvement in pes equinus, genu recurvatum and scissoring tendency, while little change was observed in crouch gait and hind foot instability. These effects have been sustained on follow-up evaluation. The gait speed, deviation to normal gait, and instability in walking were significantly improved after block and on follow-up. Maintenance of adequate range of motion and good standing balance were the most important contributing factors determining the success in phenol block. Initial spasticity, initial and post LRS score were not significant. CONCLUSION: After phenol block, spasticity returned back to the level of pre-block state but improvement in locomotion activity was maintained over 8 months on follow-up evaluation. The maintenance of adequate range of motion and good standing balance were the most important contributing factors determining the success in motor point block for improving locomotion activity.

Effects of Intra-Articular Injection and Subscapularis Motor Point Block on Painful Hemiplegic Shoulder

OBJECTIVE: To evaluate the effects of intra-articular injection of shoulder and subscapularis motor point block on painful hemiplegic shoulder. METHOD: Thirty painful hemiplegic shoulder of recent onset stroke were divided randomly into three groups, i.e. group I: range of motion (ROM) exercise only, group II: intra-articular injection with ROM exercise, group III: subscapularis motor point block with ROM exercise. The intra-articular injection of shoulder was done with 20 ml of normal saline, 5 ml of 1% lidocaine, and 40 mg of triamcinolone. The subscapularis motor point block was done with 5 ml of 5% phenol under electromyographic guide. The ROM in external rotation and simple X-ray of shoulder in full abduction were checked in three groups at pre-treatment and post-treatment 3 week, and the glenohumeral abduction and scapulohumeral rhythm were obtained from the shoulder X-ray. RESULTS: There were significant (p<0.05) improvements of glenohumeral abduction, external rotation, and scapulohumeral rhythm of shoulder in group II and III, but improvement of only glenohumeral abduction was significant in group I. Angular increment of glenohumeral abduction and external rotation was most significant in group III compared with other two groups. CONCLUSION: These results suggest that the intra-articular injection of shoulder and subscapularis motor point block are potentially useful techniques in the prevention and management of the painful hemiplegic shoulder.

Motor Point Block By Phenol in Spastic Cerebral Palsy

Purpose: The purpose of this study is to find out the immediate effect of motor point block using phenol on the degree of spasticity and the gait patterns of children with spastic cerebral palsy and then to ascertain the cases to which these findings are most beneficial. Subjects & Methods: We injected 5% phenol into spastic muscles of 33 cases with spastic cerebral palsy under the electromyographic monitoring. The clinical evaluation for type and severity of cerebral palsy was performed before the block and then, observations on both the degree of spasticity using 'modified Ashworth scale' and the range of motion were made before and after the procedures. Finally, the gait patterns before and after block were analyzed by using locomotion rating scale for gait analysis. Results: The degree of spasticity, which was measured with modified Ashworth scale, was reduced dramatically through our phenol block -i. E. from 2.8 to 1.2-. The limited range of motion in some cases was not increased significantly after block. The constant pes equinus state resulted in the state that heel contact is occasionally possible. There was also much improvement in genu recurvatum and scissoring tendency, while little change was observed in crouch gait and hind foot instability. The speed of gait, deviation to normal gait and instability in walking were improved significantly after block, but their locomotion state was still moderately incomplete. When comparing the different outcomes of motor point block with one another according to the cases in moderately disabled state improved most dramatically. The group with both high degree of spasticity and the full range of motion in their joints improved by far the better after motor point block. Conclusion: The immediate effect of motor point block with phenol solution can be best described as a dramatic relief of spasticity and tip toeing, but other problems such as other abnormal gait patterns and locomotion activity or state improved little, if any. The moderately disabled children with both high degree of spasticity and the full range of motion in their joint could get the best of our findings.