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PubMed1994

The effects of muscle fatigue on bone strain.

There is anecdotal evidence that bone strains may increase to the point that bone becomes susceptible to rapid failure when muscles become fatigued. To determine whether neuromuscular response could be a factor in accelerating bone failure, we tested the hypothesis that muscle fatigue causes a significant increase in peak principal and shear strains in bone. Ten adult foxhounds were subjected to rigorous exercise that caused muscular fatigue while myoelectrical activity of the quadriceps and hamstrings and strain on the distal tibia were monitored simultaneously. Ground reaction forces on the dog hindlimbs were measured before and after strain gauges had been applied to the tibia. The data show a significant shift to lower median myoelectrical frequencies in the quadriceps, indicating muscular fatigue, following the 20 min exercise period. In conjunction with this shift, peak principal and shear strains increased on both compressive and tensile cortices of the tibia and shear strain on the tensile cortex increased significantly (P = 0.02). The largest changes were along the anterior and anterolateral surfaces of the tibia, where peak principal strain increased by an average of 26-35% following muscular fatigue. The cross-sectional strain distribution was calculated at the gauge site at peak strain at the beginning of the exercise period and at peak strain after 20 min of exercise. These data show a change in strain distribution when muscle becomes fatigued. Strains on the posterior cortex of the bone showed the greatest change. Correlation analysis demonstrated a significant inverse association between median myoelectrical frequency and bone strain after 20 min of exercise (Spearman r2 = 1.00; P = 0.05). These data show that muscle fatigue may be associated with increased bone strain.

Animals↗
PubMed1998

Comparison of muscle strength of posterior cruciate-retained versus cruciate-sacrificed total knee arthroplasty.

One of the most controversial issues in total knee arthroplasty is whether to retain or sacrifice the posterior cruciate ligament (PCL). Investigators have used various methods to evaluate the influence of the PCL after total knee arthroplasty, but muscle strength evaluation has not been reported. The purpose of this study is to compare the long-term effects of PCL retention or sacrifice on muscle strength. Isokinetic testings and isometric testings were studied in patients with three different types of prosthesis design: total condylar, low contact stress rotating platform (both sacrifice PCL), and low contact stress meniscal bearing (retains PCL). The results showed that in all testing conditions, the hamstring to quadriceps ratios did not significantly differ among the three prosthetic designs (P > .05) even after long-term (6-13 years) functional adaptation.

Aged↗
PubMedDate not supplied

Muscular coactivation. The role of the antagonist musculature in maintaining knee stability.

The objective of this study was to quantify the coactivation patterns of the knee flexor and extensor muscles as part of continued efforts to identify the role of the antagonist muscles in maintaining joint stability. The simultaneous EMG from the flexor and extensor muscles of the knee were recorded during maximal effort, slow isokinetic contractions (15 deg/sec) on the plane parallel to the ground to eliminate the effect of gravity. The processed EMG from the antagonist muscle was normalized with respect to its EMG as agonist at maximal effort for each joint angle. The plots of normalized antagonist EMG versus joint angle for each muscle group were shown to relate inversely to their moment arm variations over the joint range of motion. Additional calculations demonstrated that the antagonist exerts nearly constant opposing torque throughout joint range of motion. Comparison of data recorded from normal healthy subjects with that of high performance athletes with hypertrophied quadriceps demonstrated strong inhibitory effects on the hamstrings coactivations. Athletes who routinely exercise their hamstrings, however, had a coactivation response similar to that of normal subjects. We concluded that coactivation of the antagonist is necessary to aid the ligaments in maintaining joint stability, equalizing the articular surface pressure distribution, and regulating the joint's mechanical impedance. The reduced coactivation pattern of the unexercised antagonist to a hypertrophied muscle increases the risk of ligamentous damage, as well as demonstrates the adaptive properties of the antagonist muscle in response to exercise. It was also concluded that reduced risk of knee injuries in high performance athletes with muscular imbalance could result from complementary resistive exercise of the antagonist muscle.

Adolescent↗
PubMed2002

Understanding muscle coordination of the human leg with dynamical simulations.

Muscles coordinate multijoint motion by generating forces that cause reaction forces throughout the body. Thus, a muscle can redistribute existing segmental energy by accelerating some segments and decelerating others. In the process, a muscle may also produce or absorb energy, in which case its summed energetic effect on the segments is positive or negative, respectively. This Borelli Lecture shows how dynamical simulations derived from musculoskeletal models reveal muscle-induced segmental energy redistribution and muscle co-functions and synergies. Synergy occurs when co-excited muscles distribute segmental energy differently to execute the motor task. In maximum height jumping, high vertical velocity at lift-off occurs desirably at full body extension because biarticular leg muscles redistribute the energy produced by the uniarticular leg muscles. In pedaling, synergistic ankle plantarflexor force generation during leg extension allows the high energy produced by the uniarticular hip and knee extensors to be delivered to the crank. An analogous less-powerful flexor synergy exists during leg flexion. Hamstrings reduce crank deceleration during the leg extension-to-flexion transition by not only producing energy but delivering it to the crank through its contribution to the tangential (accelerating) crank force, though this hamstrings function occurs at the opposite (flexion-extension) transition when pedaling backwards. In walking, the eccentric quadriceps activity in early stance not only decelerates the leg but also accelerates the trunk. In mid-stance, the uni- and biarticular plantarflexors, by having opposite segmental energetic effects, act in synergy to support the whole body, so segmental potential and kinetic energy exchange can occur. To conclude, the extraction of unmeasurable variables from dynamical simulations emulating task kinematics, kinetics, and EMGs shows how the production of force and energy by individual muscles contribute to the energy flow among the individual segments during task execution.

Bicycling↗
PubMed1998

Anterior cruciate ligament strain in-vivo: a review of previous work.

Disruption of the anterior cruciate ligament (ACL), a primary stabilizer of the knee, can produce disability. The purpose of our work has been to study the normal ACL in humans, in the presence of normal muscle function and body weight, and develop clinical criteria for reconstruction, establish a basis for rehabilitation programs, and evaluate how knee braces protect this important ligament. The strain behavior of the ACL has been measured by arthroscopic implantation of the Differential Variable Reluctance Transducer while subjects are under local anesthesia. Movement of the knee from a flexed to an extended position, either passively or through contraction of the leg muscles, produces an increase in ACL strain values. Isolated contraction of the dominant quadriceps with the knee between 50 degrees and extension creates substantial increases in strain. In contrast, isolated contraction of the hamstrings at any knee position does not increase strain. With the knee un-weighted, the protective strain shielding effect of a functional knee brace decreases as the magnitude of anterior shear load applied to the tibia increases. A different behavior occurs during weight bearing, the strain shielding effect of the brace remains constant as the magnitude of anterior load increases. Our approach is novel in that it can be used to measure on important portion of the ACLs strain distribution while clinically relevant loads are applied to the knee, subjects perform rehabilitation exercises, or in the presence of different orthoses such as functional knee braces.

Anterior Cruciate Ligament↗
PubMed2006

Slip-related muscle activation patterns in the stance leg during walking.

Falls precipitated by slipping are a serious public health concern especially in the elderly. Muscular responses generated during slipping have not been investigated during gait on contaminated floors. This study compared slip-related muscular responses (reactive and proactive) in young and older adults and examined if characteristics of muscular activation patterns during normal gait impact slip severity on contaminated floors. Electromyographic recordings were made from the major shank and thigh muscles in the stance leg of 11 young and nine older adults. Three experimental conditions were included: (1) known dry floors (baseline), (2) unexpected contaminated floor, (3) alert dry (subjects uncertain of the floor's contaminant condition). Muscular responses to unexpected slips, similar in both age groups, included the activation of the Medial Hamstring (approximately 175 ms) followed by the onset of the Vastus Lateralis (approximately 240 ms). The power and duration of responses were scaled to slip severity. The Vastus Lateralis latency was delayed in severe slips. When experiencing a severe slip, young adults demonstrated a longer, more powerful response compared to older adults. Subjects who normally walk with greater ankle muscle co-contraction were predisposed to experience less severe slips when encountering an unexpected slippery floor. Finally, anticipation of a slippery surface resulted in more powerful muscular activity and muscle co-contraction at the ankle and knee compared to baseline gait, as well as earlier onsets and longer durations in the posterior muscles' activation. These findings may provide a greater understanding of the higher incidence of falls in the elderly.

Accidental Falls↗
PubMed2002

Effects of electrical muscle stimulation on body composition, muscle strength, and physical appearance.

Electrical muscle stimulation devices (EMS) have been advertised to increase muscle strength, to decrease body weight and body fat, and to improve muscle firmness and tone in healthy individuals. This study sought to test those claims. Twenty-seven college-aged volunteers were assigned to either an EMS (n = 16) or control group (n = 11). The EMS group underwent stimulation 3 times per week following the manufacturer's recommendations, whereas the control group underwent concurrent sham stimulation sessions. Bilaterally, the muscles stimulated included the biceps femoris, quadriceps, biceps, triceps, and abdominals (rectus abdominus and obliques). An identical pre- and posttesting battery included measurements of body weight, body fat (via skinfolds), girths, isometric and isokinetic strength (biceps, triceps, quadriceps, hamstrings), and appearance (via photographs from the front, side, and back). EMS had no significant effect on the any of the measured parameters. Thus, claims relative to the effectiveness of EMS for the apparently healthy individual are not supported by the findings of this study.

Adolescent↗
PubMed2003

Neuromuscular disorder in response to anterior cruciate ligament creep.

OBJECTIVE: To determine the effect of creep developed in the anterior cruciate ligament and other viscoelastic knee structures on the function of the flexor and extensor muscles of males and females. DESIGN: Static load applied to the proximal tibia of young healthy male and female subjects in a laboratory setting with maximal voluntary knee flexion and extension performed before and after the load application. BACKGROUND: Static loads applied to various joints during occupational and sports activities are epidemiologically linked to higher than normal rates of disability reports. The physiological and biomechanical processes active in the development of such a neuromuscular disorder are not known. We hypothesize that creep developed in the anterior cruciate ligament due to prolonged static load will have pronounced impact on the reflexive activation of the associated musculature in a manner that may increase the risk of injury. Females are expected to be exposed to higher risk than males. METHODS: Male and female groups performed maximal voluntary knee flexion and extension before and after applying 200 and 150 N, respectively, to the proximal tibia for a 10 min period. Flexion and extension forces as well as electromyograph from agonist and antagonist muscles were measured at 35 degrees and 90 degrees knee flexion. Data was analyzed through repeated measures of analysis of variance. RESULTS: It was found that in extension, quadriceps electromyographic activity increased significantly after anterior cruciate ligament creep while hamstrings co-activation did not change. There was also a trend towards increased extension force after creep was developed, with significant effect of gender (larger increase in females). Similarly, significant increase in hamstrings electromyographic activity and a trend towards increased force during knee flexion was observed but with no effect of gender. Electromyographic spasms from the flexors and extensors were recorded in 30% of the subjects during the 10 min static loading period at 90 degrees angle and from the flexors only at 35 degrees. Creep in the ligament was marginally greater in females than in males with a significant effect of angle, being greater at 35 degrees than in 90 degrees knee flexion. CONCLUSIONS: The results suggest that ligament creep may develop a neuromuscular disorder consisting of spasms, increased electromyography and force in the agonist muscles without compensation from the antagonist. Static loading of a joint, therefore, may develop a neuromuscular disorder compounded with laxity of the ligaments and subject the individual to increased risk of injury. RELEVANCE: The data provides evidence that prolonged static loads applied to the anterior cruciate ligament and associated viscoelastic structures results in unbalanced muscular activation which puts individuals at increased exposure to injury. Work and sports activities should be scheduled while minimizing periods of static joint loading and emphasizing sufficient rest periods to allow recovery of creep and return to balanced muscular activation and co-activation.

Adaptation, Physiological↗
PubMed2005

Risk factors for hamstring injuries in community level Australian football.

OBJECTIVES: To identify risk factors for hamstring injury at the community level of Australian football. METHODS: A total of 126 community level Australian football players participated in this prospective cohort study. To provide baseline measurements, they completed a questionnaire and had a musculoskeletal screen during the 2000 preseason. All were monitored over the season. Injury surveillance and exposure data were collected for the full season. Survival analysis was used to identify independent predictors of hamstring injury. RESULTS: A hamstring injury was the first injury of the season in 20 players (16%). After adjustment for exposure, increasing age and decreased quadriceps flexibility were identified as significant independent predictors of the time to sustaining a hamstring injury. Older age (> or =23 years) was associated with an increased risk of hamstring injury (RR 3.8; 95% confidence interval (CI) 1.1 to 14.0; p = 0.044). Players with increased quadriceps flexibility (as measured by the modified Thomas test) were less likely to sustain a hamstring injury (RR 0.3; 95% CI 0.1 to 0.8; p = 0.022). CONCLUSIONS: The findings of this study can be used in the development of hamstring injury prevention strategies and to identify Australian football players at increased risk of hamstring injury.

Adult↗
PubMed2005

Abdominal strengthening using the AbVice machine as measured by surface electromyographic activation levels.

Twenty-four college students served as subjects in a study that examined the effect of a prototypical abdominal muscle strengthening device (AbVice) compared with other devices currently on the market. The purpose of the present study was to investigate a prototypical device (AbVice) that incorporates contraction of the hamstring and gluteal musculature in conjunction with the abdominals, which may assist in decreasing activation of the hip flexors by allowing greater activity levels of the abdominal musculature via the theory of reflex inhibition, compared with other devices currently available on the market (AbRoller and AbRocker). The repeated-measures study included 17 women and 7 men who ranged in age from 20-23 years (mean +/- SD age, 21.3 +/- 1.5 years). Each subject underwent a single session of data collection during which they completed 10 repetitions of abdominal crunches per device. Subjects completed 4 different crunch sets (AbRocker, AbRoller, standard crunch, AbVice). Counterbalancing of the device was used to negate the effect of fatigue. Speed of repetitions was ensured via use of a metronome set at 40 b.min(-1) to permit similar contraction times and rest periods between repetitions. Rest between conditions was 3 minutes. Mean activation levels of surface electromyography (EMG) were recorded for each condition at the following locations on the right side of the body: rectus abdominis 2.5 cm superior to the umbilicus, rectus abdominis 2.5 cm inferior to the umbilicus, external oblique abdominis 1.0 cm medial to the anterior superior iliac spine, and external oblique abdominis less than 1.0 cm superior to the inguinal ligament. Mean (SD) activation was 1,165.21 mV (634.60 mV) with the AbVice, 242.92 mV (263.03 mV) with the AbRocker, 753.29 mV (514.80 mV) with the standard crunch, and 757.67 mV (542.85 mV) with the AbRoller. Broken down by sex, women had the following mean (SD) EMG values: 1,079.76 mV (705.02 mV) with the AbVice, 680.35 mV (535.35 mV) with the standard crunch, 262.70 mV (305.89 mV) with the AbRocker, and 636.88 mV (502.82 mV) with the AbRoller. Men demonstrated mean (SD) values of 1,372 mV (383.87 mV) with the AbVice, 1,051 mV (560.09 mV) with the AbRoller, 930.43 mV (447.17 mV) with the standard crunch, and 194.86 mV (109.05 mV) with the AbRocker. Two-way analysis of variance with factor 1 (person) and factor 2 (condition) had F values of 11.73 and 36.04, respectively. Post hoc analysis using the Tukey test indicated that all comparisons between conditions were significant at the p = 0.01 level except for the standard crunch vs. the AbRoller. The AbVice activated the selected abdominal musculature more effectively than the other conditions.

Abdominal Muscles↗
PubMed1992

Control of an external force in leg extensions in humans.

1. We investigated the hypothesis that mono- and bi-articular muscles perform different functions: the former are chiefly dependent on their mechanical advantage, while the latter are considered to be mainly concerned with controlling the direction of an external force. 2. Seven subjects were asked to exert a constant external force in various directions from three different positions. Feedback was given on the amplitude (300 and 600 N) and direction of the force vector. 3. During each trial the position of the subject was registered. Ground reaction force and muscle activity (EMG) from the main mono- and bi-articular upper leg muscles were recorded. Link segment modelling was used to obtain net moments about the knee and hip joints. For each muscle the mechanical advantage was calculated in each force direction. 4. The task of controlling the ground reaction force was performed with little interindividual variation as reflected by the variability of the different force and EMG variables. 5. A linear relationship between the difference in activity of rectus femoris and hamstrings and the difference in net moment around the knee and hip was found. This relationship showed very high correlation coefficients of 0.96 (300 N) and 0.97 (600 N) and was independent of position. Mean correlations between this activity difference and the angle of the force vector were also high: -0.95 (300 N) and -0.94 (600 N). 6. The mono- as well as the bi-articular muscles increased in activity when a larger mechanical advantage could be obtained from them, except for the biceps femoris (short head). 7. The results support the hypothesis that bi-articular muscles have a unique role in controlling the distribution of net moments about the joints, and as a consequence, in controlling the direction of the external force exerted on the environment.

Biomechanical Phenomena↗
PubMedDate not supplied

Effects of therapeutic passive exercise of hip and knee joints on the soleus H-reflex.

UNLABELLED: The effect of passive movement of a leg on alpha-motoneurons of the soleus was investigated while the ankle was immobilized. Electrophysiological parameters of the H-reflex were used. Nineteen fully informed volunteers with no history of neurological or internal disease participated in the study. The mean age across all the experiments was 20.9 years. Contributions to the modulation of the soleus H-reflex by hip and knee joint movements were analyzed in two tasks. These were the most general movement methods used in physical therapy. Soleus H-reflexes were measured six times per experiment. Stimulation intensity was set at the 1.1 x M-wave threshold. RESULTS: 1. In both exercises, H/M decreased as flexion progressed with fast or slow movement. The quadriceps femoris inhibited soleus muscle alpha-motoneurons in both experiments. 2. H/M increased on initiation of extension in the two-joint exercise. In the single-joint exercise, inhibition was retained through the extension phase during both fast and slow movements. Hamstring effects were strong during extension of the leg. 3. In both exercises, the H/M for fast movement was lower than for slow movement at all angles, indicative that H/M decreases with fast movement irrespective of the effects produced by the hip joint.

Adult↗
PubMed2005

Skeletal muscle fatigue, strength, and quality in the elderly: the Health ABC Study.

We examined the muscle fatigue characteristics in older men and women and determined whether these were related to the size, strength, or quality of muscle. A total of 1,512 men and women aged 70-79 yr from the Health, Aging, and Body Composition Study participated in this study. Muscle cross-sectional area and attenuation were determined with computed tomography. Skeletal muscle fatigue and strength (peak torque) of the knee extensors and flexors were measured using isokinetic dynamometry. Men were more fatigue resistant than women for both knee extension (fatigue index: 70.4 +/- 15.3 vs. 66.9 +/- 14.3%; P < 0.05) and knee flexion (67.9 +/- 16.4 vs. 64.9 +/- 17.6%; P < 0.05). Peak torque and muscle quality (specific torque) were higher in men than women for knee extension (99.6 +/- 28.2 vs. 63.0 +/- 16.8 N x m and 1.62 +/- 0.43 vs. 1.51 +/- 0.39 N x m/cm2; both P < 0.05) and for knee flexion (74.0 +/- 26.4 vs. 49.6 +/- 15.9 N x m and 2.47 +/- 1.29 vs. 2.22 +/- 0.78 N x m/cm2; both P < 0.05). Total work and power output was greater in men compared with women for both the quadriceps (1,353 +/- 451 vs. 832 +/- 264 J and 87.7 +/- 33.5 vs. 53.3 +/- 19.2 W; both P < 0.05) and the hamstrings (741 +/- 244 vs. 510 +/- 141 J and 35.4 +/- 16.0 vs. 23.7 +/- 10.2 W; both P < 0.05). In both genders, the quadriceps was able to perform more work with greater power compared with the hamstrings. Those who were stronger actually had greater fatigue after adjusting for age, race, physical activity, and total body fat. In conclusion, older men were more fatigue resistant than women, although in both men and women greater fatigue was not related to muscle weakness.

Aged↗
PubMed1999

Quadriceps strength in women with radiographically progressive osteoarthritis of the knee and those with stable radiographic changes.

OBJECTIVE: To explore the relationship between lower extremity weakness and the progression of established radiographic changes of knee osteoarthritis (OA). METHODS: The study cohort of 342 elderly subjects was recruited from central Indiana by random digit dialing. We analyzed 79 subjects who had definite radiographic changes of unilateral or bilateral knee OA at baseline and for whom baseline data for lower extremity muscle strength and lean tissue mass and baseline and followup assessments of knee pain were available. Radiographs were graded for severity of OA at baseline and again about 2.5 years later (mean 31.5 months). Knee pain was evaluated at the same examination. Strength of the knee flexors and extensors was assessed bilaterally at baseline by isokinetic dynamometry and lower extremity muscle mass by dual energy x-ray absorptiometry. RESULTS: Mean peak knee extensor strength of women with progressive OA, before and after adjustment for lower extremity muscle mass, was about 9% lower than that in those with stable radiographic changes, but this difference was not statistically significant. No difference was apparent between the 2 groups with respect to knee flexor (hamstring) strength. The decrease in quadriceps strength among women with progressive OA, relative to those with stable OA, did not appear to be attributable to knee pain, and knee extensor strength at baseline bore no apparent relationship to the development or progression of knee pain among those with OA. CONCLUSION: We have shown previously that quadriceps weakness may be of etiologic importance in development of knee OA. The absence of a significant difference in quadriceps strength between subjects with radiographically stable OA and those whose joint damage progressed suggests that factors other than quadriceps weakness are more important determinants of OA progression.

Aged↗
PubMed1996

Role of cocontraction in the O2 cost of walking in children with cerebral palsy.

UNLABELLED: A major movement related limitation for children with spastic cerebral palsy (CP) is the compromised gait pattern, which may explain their excessive energy cost of locomotion. The aims of this study were to determine differences in the O2 cost of locomotion between children with CP (7 males, 2 females; 12.7 +/- 2.8 yr) and able-bodied controls (7 male, 1 female; 13.6 +/- 2.1 yr) and to assess the contribution that cocontraction of agonist and antagonist muscles had upon the elevated O2 cost seen in children with CP versus able-bodied controls. The treadmill submaximal walking protocol consisted of 2 x 4 min intermittent stages at 3 km.h-1 and 90% of the predetermined fastest walking speed (FWS) at 0% grade. Electromyographic data were collected during the final minute of each bout from vastus lateralis and hamstrings (thigh) and tibialis anterior and soleus (lower leg). Significant (P < 0.05) differences were noted at 3 km.h-1 for mass-relative VO2. (CP: 16.6 +/- 6.5 vs control: 10.2 +/- 1.2 ml.kg-1.min-1), % VO2max (CP: 53.5 +/- 26.0 vs CONTROL: 22.5 +/- 4.93) and heart rate (CP: 143 +/- 41 vs CONTROL: 91 +/- 14 beats.min-1). Thigh and lower leg muscle cocontraction accounted for 51.4% and 42.8%, respectively, of the variability in VO2 for the subjects with CP at 3 km.h-1. These results suggest that cocontraction is a major factor responsible for the higher energy cost of walking seen in children with CP.

Adolescent↗
PubMed2001

The motor dysfunction of patients with knee osteoarthritis in a Chinese population.

OBJECTIVE: To determine the extent of motor dysfunction in people with knee osteoarthritis (OA), as compared with similarly aged subjects without knee OA, in a Chinese population. METHODS: Seventy-six subjects participated in this study. Isometric peak torque of the knee muscles, range of knee motion at rest and during walking, gait velocity, cadence, and stride length were compared. RESULTS: The isometric peak torque of both the quadriceps and the hamstrings of the affected leg of patients with knee OA were weaker than those of the controls (most P < 0.05). The gait velocity was 23.4% slower (P = 0.001), the cadence 33.3% less (P < 0.001), and the stride length 13.4% shorter (P = 0.010) in the patients with OA. The range of knee motion in the patients was reduced by 11.2% at rest (P = 0.003) and by 14.7% during walking (P = 0.001). CONCLUSION: Patients with knee OA exhibited statistically significant deficiencies in the physical performance tested, as compared with similarly aged subjects without knee OA (by 9.6% to 33.3%), in a Chinese population. The indication that this study group seems less severely limited than those reported in Western literature warrants further investigation.

Aged↗
PubMed2006

The use of botulinum toxin therapy for lower-extremity spasticity in children with cerebral palsy.

Hypertonicity is a leading cause of disability for children with cerebral palsy (CP). Botulinum toxin A (BTA) chemically denervates muscle tissue and is commonly used in the management of lower-extremity hypertonicity in children with CP because of its focal effects and wide safety margin. Randomized controlled trials have demonstrated that BTA injections in the ankle flexors, hamstrings, and adductors reduce spasticity and result in improved passive and active range of motion. In other studies, improvements in gait and measurements of functional outcome were found in appropriately selected children who had been injected with BTA. A multidisciplinary treatment approach that includes physical therapists, occupational therapists, orthotists, neurologists, physicians with expertise in performing botulinum toxin injections, orthopedic surgeons, and neurosurgeons is critical to optimize care in children with lower-extremity tone due to CP. In this paper, the authors propose treatment algorithms based on clinical presentation, detailed dosing, and technical information to optimize the treatment of these children. With a multidisciplinary approach, children with lower-extremity hypertonicity due to CP can experience improvements in muscle tone and function.

Algorithms↗