Double-blind study of botulinum A toxin injections into the gastrocnemius muscle in patients with cerebral palsy.

The purpose of this study was to quantify the gait of subjects receiving two injections of either botulinum A toxin or saline vehicle into the gastrocnemius muscle(s). The study group consisted of cerebral palsy patients who walked with an equinus gait pattern. This study was a randomized, double-blinded, parallel clinical trial of 20 subjects. All were studied by gait analysis before and after the injections. There were no adverse effects. Peak ankle dorsiflexion in stance and swing significantly improved in subjects who received the drug and not in controls. Results of this double blind study give support to the short term efficacy of botulinum toxin A to improve gait in selected patients with cerebral palsy.

Femoral anteversion and neck-shaft angle in children with cerebral palsy.

A database of femoral anteversion and neck-shaft angle was compiled of measurements made by the trigonometric fluoroscopic method of 147 patients (267 hips) with cerebral palsy. The angles of femoral anteversion were similar at early ages between healthy children and children with cerebral palsy. However, as the age of the children increased, those with cerebral palsy showed little change in anteversion angle, whereas the healthy children had progressively decreasing angles of femoral anteversion as they approached adulthood. The neck-shaft angle was increased significantly in children with cerebral palsy compared with the angles of healthy children. Patients who were ambulatory were shown to have an increased angle of femoral anteversion and a decreased neck-shaft angle compared with nonambulatory patients. There was no significant difference in angles among the various distributions of involvement, including patients with diplegia, hemiplegia, and quadriplegia.

Kinematic and kinetic analysis of distal derotational osteotomy of the leg in children with cerebral palsy.

Patients with cerebral palsy often develop rotational deformities of the lower extremities. These deformities may be caused by abnormal muscle tone, soft-tissue contractures, or bony malalignment. When rotational deformity persists after correction of the soft-tissue components, bony-realignment procedures are warranted to improve gait in ambulatory patients. We performed a retrospective review of 10 ambulatory children with cerebral palsy and tibial torsion who underwent 13 distal tibial and fibular derotation osteotomies. Preoperative and postoperative three-dimensional gait analysis were used to determine the effect of distal tibial and fibular derotation osteotomy on tibial rotation, foot-progression angle, gait velocity, and moments about the ankle. Mean tibial rotation and foot-progression angle were significantly improved by the procedure. Gait velocity improved but not significantly. Moment data demonstrated a trend toward normal. This study demonstrates that the derotational distal tibial and fibular osteotomy stabilized with percutaneous crossed Kirschner wires is a safe, reliable, and effective procedure for correcting rotational deformities of the leg in patients with cerebral palsy.

Psoas release at the pelvic brim in ambulatory patients with cerebral palsy: operative technique and functional outcome.

Seventeen patients with cerebral palsy (29 hips) underwent psoas recession at the pelvic brim. The operative technique was a direct anterior approach, lateral to the femoral sheath. There were no infections or nerve or arterial injuries. After surgery, clinical examination revealed that fixed hip-flexion contractures decreased significantly in all patients. All of the subjects retained the ability to flex the hip against gravity and against manual resistance. All of the subjects underwent pre- and postoperative gait analysis. Stance-phase dynamic minimum hip flexion decreased significantly. Dynamic pelvic tilt improved to a statistically significant level for the younger children but did not for the group as a whole. There was less improvement with increasing age. Step length was significantly increased and cadence significantly decreased in all patients. We conclude that psoas recession at the pelvic brim, by using the anterior approach, lateral to the femoral sheath, is a safe, reliable, and effective procedure for children with cerebral palsy who have excessive anterior pelvic tilt and excessive dynamic hip flexion or hip-flexion contracture.

Gait laboratory analysis of a posterior cruciate-sparing total knee arthroplasty in stair ascent and descent.

Successful posterior cruciate ligament-sparing total knee arthroplasty functions in an equivalent fashion to a contralateral normal limb during the mechanical stresses of stair ascent and descent. Motion and force plate analysis reveal highly symmetric gait patterns. Sagittal angles are greater than previously reported for the total condylar prosthesis and are nearly equal to those recorded for the age-matched normal population.

The effect of surface and internal electrodes on the gait of children with cerebral palsy, spastic diplegic type.

The purpose of this study was to determine whether surface and internal fine-wire electromyography electrodes had an effect on gait. The subjects for the experiments were 38 children with the spastic diplegic type of cerebral palsy. The children were filmed using the high-speed cinematographic technique while they walked (a) with no electrodes (unencumbered), (b) with only surface electrodes, and (c) with internal electrodes. Single stance time, step length, cadence, and walking velocity were compared with analysis of variance and Bonferroni t tests. The results included a significant decrease in cadence (-6.3% of unencumbered walking; p less than 0.05) when comparing walking with surface electrodes with walking without any electrodes. The internal electrodes caused significant decreases from normal walking in the following parameters: step length for both the measured leg (-18.6%; p less than 0.005) and the nonmeasured leg (-18.0%; p less than 0.005), cadence (-7.9%; p less than 0.02), and walking velocity (-23.5%; p less than 0.005). Internal electrodes caused significant decreases as compared with surface electrodes in the step length for both the measured leg (15.7%; p less than 0.01) and the nonmeasured leg (15.6%; p less than 0.005) and walking velocity (19.7%; p less than 0.005). Single stance phase did not change significantly in any of the comparisons. It appears that the addition of the surface electrode apparatus does change the normal gait of a subject, causing a large decrease in cadence. The measurement of gait with internal electrodes causes further change in gait, resulting in large decreases in step length and walking velocity.(ABSTRACT TRUNCATED AT 250 WORDS)

Vibratory hypersensitivity in idiopathic scoliosis.

This study determined whether a significant difference in response to vibratory stimuli was consistently present in a large group of children with idiopathic scoliosis as compared with age-matched controls. Fifty-eight unselected adolescent females with documented progressive idiopathic scoliosis were studied along with age-matched controls. Threshold to detection of a vibratory stimulus was measured in both the right and left upper and lower extremities. Results indicated that highly significant differences existed between scoliotic children and controls at all sites tested (p less than 0.01), with scoliotic children being more sensitive than controls. The results support the presence of a central aberration in posterior column function that may be a primary etiology of idiopathic scoliosis.

Vibratory response in idiopathic scoliosis.

Recent clinical studies have suggested that a neurological lesion may be a cause of adolescent idiopathic scoliosis and animal experiments have implicated the posterior column pathway. We have tried to determine if differences in neurological response could be detected and measured clinically, and have compared the threshold of detection of vibratory sensation in 20 girls with adolescent idiopathic scoliosis with that in 20 clinically normal age-matched controls. A highly significant reduction of the threshold of detection of vibration was seen in the scoliotic group compared to the controls (p less than 0.001). Curve magnitude did not correlate with this threshold for either the upper (r = 0.172) or lower extremity (r = 0.126). Significant asymmetry between right- and left-sided thresholds to vibration was demonstrated in the scoliotic group. Our study supports the concept that an aberration in the function of the posterior column pathway of the cord may be of primary importance in the aetiology of idiopathic scoliosis. A clinically practical test to measure this function is presented.

Exercise-related knee joint laxity.

Knee injuries are the topic of increasingly sophisticated research because of the importance in professional athletics as well as increasing participation in recreational sports. The role of conditioning and fatigue in these injuries remains controversial. Ligaments have high collagen content, and a viscoelastic response to stress would be expected. Because of the postulated relationship between laxity and knee ligament injuries, an experiment was designed using highly motivated athletes to test the hypothesis that exercise to the point of muscular fatigue may cause laxity of the knee and thereby place athletes at risk for ligamentous injury to the knee when fatigued. An exercise protocol was designed to produce muscle fatigue in the hamstring and quadriceps muscle groups. Knee ligament laxity was tested prior to and subsequent to the exercise protocol. To document muscle fatigue, isokinetic testing of right knee flexion and extension power was used several times during the exercise protocol. A knee arthrometer (KT-1000) was used to quantitatively document ligamentous laxity before and after exercise. The results indicated a significant lengthening in knee joint laxity between preexercise and postexercise in the left knee as measured at 15 and 20 pounds of passive displacement force (P less than 0.05). Maximum manual displacement also demonstrated a significant increase in joint laxity (P = 0.02). The right knee, which had undergone isokinetic testing, demonstrated a similar tendency but without a statistically significant difference before and after exercise. There was no significant preexercise side to side difference, but postexercise measurements demonstrated a left-right difference at 15 pounds, 20 pounds, and maximum manual displacement of statistical significance (P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of fatigue on joint position sense of the knee.

This study was designed to test position sense of the knee joint before and after fatigue in order to determine whether muscle or capsular receptors are the primary sensors for joint position sense. Reproduction of passive positioning and detection of the onset of motion (kinesthesia) were employed to measure joint position sense. Eleven subjects underwent joint position sense measurement before and after a fatigue protocol. A significant worsening of reproduction of knee joint angle after fatigue was noted (p less than 0.05). Threshold (kinesthesia) showed no statistically significant change after fatigue. A significant correlation of reproduction measurements and threshold measurements prior to fatigue (p less than 0.01) demonstrated that the same neural mechanism is applicable in the rested state, but these variables did not correlate significantly after fatigue. There was a significant correlation between reproduction measurements before and after fatigue (p = 0.018), while no correlation was seen for the pre- and postfatigue threshold measurements, suggesting a change in the neural path after fatigue. Since both tests of joint position sense are affected by fatigue, we conclude that muscle receptors are a prominent, if not primary, determinant of joint position sense, and capsular receptors may have a secondary role. Reproduction ability is decreased, presumably through the loss of efficiency of muscle receptors. The threshold data suggest a change in the mechanism of appreciation after fatigue, possibly due to increased sensitivity of capsular receptors from muscle-fatigue-induced laxity.

Comparison of Quadriceps and Hamstring Torque Values during lsokinetic Exercise.

Maximal voluntary muscular torque output of the quadriceps and hamstrings during isokinetic exercise was studied. Both knees of 50 male and 50 female subjects between the ages of 25 and 34 were tested at 60, 180, and 300" per second on the Cybex II isokinetic dynamometer. The means, standard deviations, ranges, absolute value differences, and analysis of variance were calculated on the torque values. The findings were that 1) torque values decreased as speed of exercise increased; 2) quadriceps torque values were significantly greater than the hamstrings at each test speed; 3) the ratio of hamstring torque values to quadriceps torque values significantly increased as the test speed increased; 4) dominant and nondominant knee torque values differed significantly for the males but not for the females; 5) the ratio of nondominant to dominant knee torque values was equal to or greater than 97% in all tests; and 6) the absolute difference in torque values between each subject's knees was 12 foot-pounds or less. J Orthop Sports Phys Ther 1981;3(2):48-56.