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PubMed2003

The effects of a neuromuscular electrical stimulation home program on impairments and functional skills of a child with spastic diplegic cerebral palsy: a case report.

PURPOSE: To examine the effects of neuromuscular electrical stimulation (NMES) on impairments and functional skills of a 13-year-old child with spastic diplegic cerebral palsy (CP). METHODS: NMES was administered to the right quadriceps muscles every other day for six weeks. Pre- and posttesting included assessment of strength using a hand-held dynamometer, spasticity using a KinCom isokinetic dynamometer, gait spatiotemporal parameters using GAITRite, and functional motor performance with the use of the Pediatric Evaluation of Disability Inventory (PEDI). RESULTS: After intervention, right quadriceps strength increased from 16.3 +/- 3.06 to 41.7 +/- 4.2 Newtons. Right hamstring spasticity decreased at three tested velocities. In the untreated left lower extremity, strength remained unchanged but spasticity increased. The PEDI showed development of new skills, including the ability to climb stairs with less assistance. CONCLUSION: These findings indicate that NMES was an effective therapeutic technique to improve strength and motor function of a child with spastic diplegic CP.

Journal Article↗

PubMed2005

Novel biomechanics demonstrate gait dysfunction due to hamstring tightness.

BACKGROUND: Children with cerebral palsy and hamstring tightness often demonstrate limited terminal swing knee extension. The conventional clinical measure of popliteal angle describes static hamstring tightness, but is not consistent with dynamic limitation. We hypothesize hamstring tightness, determined via modification of the conventional popliteal angle measure, is directly related to decreased terminal swing knee extension in children with cerebral palsy and normal magnitude knee flexion moments. METHODS: Six patients with cerebral palsy and six normal subjects were evaluated via physical examination and instrumented gait analysis. Physical examination included popliteal angle measures at first hamstring resistance to passive extension (R(1)), and end-range extension (R(2)) with the hip in varying degrees of flexion. Passive R(1) data were used to calculate regression equations to predict R(1) during gait, resulting in a novel measure of Available Knee Extension. Hamstring EMG was also compared. FINDINGS: R(1) during physical examination was significantly correlated with Available Knee Extension at terminal swing (Pearson r = -0.7251, P < 0.0001). Patients walked with significantly decreased velocity (0.959 vs. 1.27 m/s, P = 0.0002) and decreased knee extension at terminal swing (25.6 vs. 2.05 degrees, P < 0.0001), in the presence of normal knee flexion moments (-0.289 vs. -0.306 Nm/kg, P = 0.5009), and significantly decreased power absorption (-0.821 vs. -1.43 W/kg, P < 0.0001). Eleven of 12 patient knees demonstrated negative Available Knee Extension at terminal swing, with markedly limited knee extension. Five of 12 normal knees demonstrated negative Available Knee Extension, but this was near full extension. Hamstring EMG onset times were not significantly different. INTERPRETATION: We believe Available Knee Extension, defined on the basis of clinical measures of first resistance to hamstring stretch, provides a biomechanical link between physical examination findings and dynamic limitations in terminal swing knee extension.

Biomechanical Phenomena↗

PubMed1999

Isokinetic evaluation of anterior cruciate ligament reconstruction: hamstring versus patellar tendon.

The purpose of the study was to compare the hamstring and quadriceps isokinetic results 6 months postoperatively in patients having patellar tendon or hamstring anterior cruciate ligament (ACL) reconstruction. The study group was comprised of 106 randomly selected patients who had ACL reconstruction with either autogenous patellar tendon (PT), semitendinosus (ST), or semitendinosus and gracilis (ST/G). Hamstring and quadriceps isokinetic strength were assessed at 180 degrees/sec and 300 degrees/sec with the results of the operatively treated leg expressed as a percent compared with the nonoperative leg. The mean results for knee extension at 180 degrees/sec were 68.3%, 74.3%, and 78.1%; and at 300 degrees/sec were 70.7%, 76.7%, and 81.7% for PT, ST, and ST/G, respectively. The mean results for knee flexion at 180 degrees/sec were 86.1%, 80.6%, and 81.7%; and at 300 degrees/sec were 77.6%, 79.1%, and 75.6% for PT, ST, and ST/G, respectively. No statistically significant differences were found in regard to knee extension or flexion strength when evaluating the different tissue sources. The results show that selection of autogenous hamstring or PT used for ACL reconstruction should not be based solely on the assumption of the tissue source altering the recovery of quadriceps and/or hamstring strength. In addition, a majority of the patients had not achieved adequate strength to safely partake in unlimited activities at 6 months postoperatively.

Anterior Cruciate Ligament↗

PubMed2003

Impact of prior exercise on hamstring flexibility: a comparison of proprioceptive neuromuscular facilitation and static stretching.

Position stands from the American College of Sports Medicine and the Surgeon General site a need for strategies capable of enhancing the effectiveness of stretching on flexibility and joint range of motion. One strategy for enhancing flexibility that has received anecdotal support but lacks substantial experimental evidence is the impact of prior exercise. This study compared 5 minutes of static stretching and proprioceptive neuromuscular facilitation (PNF) on hamstring flexibility performed with and without exercise. Forty undergraduate student-athletes participated in a repeated measure, counterbalanced experimental design. Within-group comparisons indicated that PNF resulted in a significant (p < 0.05) increase in flexibility after 60 minutes of exercise when compared with baseline (9.6%) and without exercise (7.8%). No differences were observed with static stretching across time. In addition, no differences were observed between the groups at any time point. Results demonstrated that PNF performed after exercise enhanced acute hamstring flexibility, and implementing a PNF stretching routine following exercise may augment current stretching practices among athletes.

Adolescent↗

PubMed2006

Changes in selected biochemical, muscular strength, power, and endurance measures during deliberate overreaching and tapering in rugby league players.

The purpose of this study was to examine the influence of overreaching on muscle strength, power, endurance and selected biochemical responses in rugby league players. Seven semi-professional rugby league players (.VO(2max) = 56.1 +/- 1.7 mL . kg (-1) . min (-1); age = 25.7 +/- 2.6 yr; BMI = 27.6 +/- 2.0) completed 6 weeks of progressive overload training with limited recovery periods. A short 7-day stepwise reduction taper immediately followed the overload period. Measures of muscular strength, power and endurance and selected biochemical parameters were taken before and after overload training and taper. Multistage fitness test running performance was significantly reduced (12.3 %) following the overload period. Although most other performance measures tended to decrease following the overload period, only peak hamstring torque at 1.05 rad . s (-1) was significantly reduced (p < 0.05). Following the taper, a significant increase in peak hamstring torque and isokinetic work at both slow (1.05 rad . s (-1)) and fast (5.25 rad . s (-1)) movement velocities were observed. Minimum clinically important performance decreases were measured in a multistage fitness test, vertical jump, 3-RM squat and 3-RM bench press and chin-up (max) following the overload period. Following the taper, minimum clinically important increases in the multistage fitness test, vertical jump, 3-RM squat and 3-RM bench press and chin-up (max) and 10-m sprint performance were observed. Compared to resting measures, the plasma testosterone to cortisol ratio, plasma glutamate, plasma glutamine to glutamate ratio and plasma creatine kinase activity demonstrated significant changes at the end of the overload training period (p < 0.05). These results suggest that muscular strength, power and endurance were reduced following the overload training, indicating a state of overreaching. The most likely explanation for the decreased performance is increased muscle damage via a decrease in the anabolic-catabolic balance.

Adult↗

PubMed1999

Does laxity alter the relationship between strength and physical function in knee osteoarthritis?

OBJECTIVE: Since strengthening interventions have had a lower-than-expected impact on patient function in studies of knee osteoarthritis (OA) and it is known that laxity influences muscle activity, this study examined whether the relationship between strength and function is weaker in the presence of laxity. METHODS: One hundred sixty-four patients with knee OA were studied. Knee OA was defined by the presence of definite osteophytes, and patients had to have at least a little difficulty with knee-requiring activities. Tests were performed to determine quadriceps and hamstring strength, varus-valgus laxity, functional status (Western Ontario and McMaster Universities Osteoarthritis Index Physical Functioning subscale [WOMAC-PF] and chair-stand performance), body mass index, and pain. High and low laxity groups were defined as above and below the sample median, respectively. RESULTS: Strength and chair-stand rates correlated (r = 0.44 to 0.52), as did strength and the WOMAC-PF score (r = -0.21 to -0.36). In multivariate analyses, greater laxity was consistently associated with a weaker relationship between strength (quadriceps or hamstring) and physical functioning (chair-stand rate or WOMAC-PF score). CONCLUSION: Varus-valgus laxity is associated with a decrease in the magnitude of the relationship between strength and physical function in knee OA. In studies examining the functional and structural consequences of resistance exercise in knee OA, stratification of analyses by varus-valgus laxity should be considered. The effect of strengthening interventions in knee OA may be enhanced by consideration of the status of the passive restraint system.

Adult↗

PubMed2005

Intrinsic and imposed hamstring length influence posterior pelvic rotation during hip flexion.

BACKGROUND: The contribution of posterior tilt of the pelvis (pelvic rotation) to hip flexion has been described for individuals who are standing, supine, and suspended. The effects of intrinsic and imposed hamstring length on the motion have not been investigated in a controlled manner. This study investigated the influence of intrinsic and imposed hamstring length on pelvic rotation during bilateral active hip flexion. METHODS: Intrinsic hamstring length was characterized by the maximal active straight leg raise angle. Hamstring length was imposed by immobilizing the knees in 0 degrees, 45 degrees, and 90 degrees of flexion. Pelvic and thigh segments were marked with reflective spheres. Subjects' saggital plane motion was captured using computerized motion analysis during bilateral hip flexion while both knees were immobilized in three positions. Multifactorial analysis of variance was employed to show the effect of intrinsic and imposed hamstring length on pelvic rotation. FINDINGS: Pelvic rotation occurred throughout the hip flexion range of motion. Pelvic rotation was influenced significantly by hip flexion angle, knee position, the interaction between hip flexion angle and knee position, and the interaction between hip flexion angle, knee position, and active straight leg raise angle. INTERPRETATION: Both intrinsic and imposed hamstring length influence pelvic rotation during bilateral hip flexion. These influences should be considered by clinicians who have individuals engage in hip flexion maneuvers.

Adult↗

PubMed2000

The efficacy of femoral nerve block in pain reduction for outpatient hamstring anterior cruciate ligament reconstruction: a double-blind, prospective, randomized trial.

The purpose of this study was to assess the efficacy of intraoperative femoral nerve block (FNB) in the reduction of postoperative pain following anterior cruciate ligament (ACL) hamstring reconstruction. Patients undergoing primary ACL reconstruction with hamstring tendon graft under general anesthetic who had signed an informed consent were included in the study. Patients were stratified to 4 surgeons and randomized to FNB with 0.25% bupivacaine or placebo of normal saline injected into the femoral nerve sheath before reversal of the general anesthetic. All patients received an intra-articular injection of bupivacaine at the beginning of their operative procedure. A single technique that included the use of a peripheral nerve stimulator was used for all FNBs. All patients were discharged on the day of surgery and given prescriptions for Tylenol 3. The Short-Form McGill Pain Questionnaire (SF-MPQ), a visual analog scale (VAS) for pain, and a medication diary recording Tylenol 3 usage were completed by patients in the recovery room, on the night of surgery, and on postoperative days 1, 2, and 3. There were complete data for 61 patients (FNB, 29; placebo, 32). An analysis of variance (ANOVA) test of the data showed no significant difference between the FNB and placebo group for pain reduction over the combined study period for both the SF-MPQ and VAS. However, the ANOVA does suggest that, on the night of surgery, there was a significant reduction in pain as measured with the VAS in the FNB group. A Student t test performed on the night of surgery data (SF-MPQ, P = .131; VAS, P = .0114; Tylenol 3, P = .076) showed a statistically significant difference between the FNB (39.4+/-21.0 mm) and placebo (56.8+/-24.6 mm) measured by VAS. Because this represented a difference of only 1.74 cm on a 10-cm VAS, it is unlikely to be clinically relevant. No difference was found in the amount of analgesic required on any day postoperatively. In conclusion, FNB may reduce pain on the night of surgery. However, this may not be clinically significant. FNB is not recommended at this time for use in outpatient ACL reconstruction with hamstring graft.

Adolescent↗

PubMed2004

Knee muscular response strategies differ by developmental level but not gender during jump landing.

The purpose of this investigation was to determine differences between pre- and post-pubescent males and females in quadriceps (vastus medialis; VM) and hamstrings (medial hamstrings and biceps femoris; HAMS) muscular activation patterns via the root mean square of surface electromyography (SEMG) during self-initiated vertical jump landing. Fifty-eight subjects, divided into age and gender groupings, were compared on kinematic variables during pre-landing (100 msec preceeding initial ground contact), post-landing (100 msec following initial ground contact), and initial-contact-to-maximum-knee-flexion stages. Kinematic variables investigated were (1) SEMG values during each stage of the vertical-jump landing; (2) Co-contraction ratios (CCR), which represented the ratio of normalized hamstrings' activity to normalized quadriceps' activity; and, (3) knee angle at initial contact. Results indicated (1) no significant gender differences in variables measured; and, (2) significant developmental level differences. Post-pubescent subjects displayed greater HAMS acitivity and CCR values in the pre-landing stage relative to post-landing stages, indicating that post-pubescent subjects had a greater level of hamstrings co-contraction prior to landing than pre-pubescent subjects. Conversely, pre-pubescent subjects displayed greater post-landing and initial-contact-to-maximum-knee-flexion ratios, indicating a greater level of hamstrings' co-contraction during post-landing stages than post-pubescent subjects. There were no significant differences in knee angle at initial contact. The greater level of hamstrings' co-activation prior to landing by post-pubescent subjects indicated that they used a strategy of pre-tuning the hamstrings prior to landing (more CNS pre-activation) to control the ground reaction forces and anterior tibial displacement experienced by the knee during landing. On the other hand, pre-pubescent subjects controlled these forces by having a greater level of hamstrings' co-activation during landing, which represents more of a reflexive activation in response to ground impact.

Adult↗

PubMed2006

Reliability of measures of impairments associated with patellofemoral pain syndrome.

BACKGROUND: The reliability and measurement error of several impairment measures used during the clinical examination of patients with patellofemoral pain syndrome (PFPS) has not been established. The purpose was to determine the inter-tester reliability and measurement error of measures of impairments associated with PFPS in patients with PFPS. METHODS: A single group repeated measures design was used. Two pairs of physical therapists participated in data collection. Examiners were blinded to each others' measurements. RESULTS: Thirty patients (age 29 +/- 8; 17 female) with PFPS participated in this study. Inter-tester reliability coefficients were substantial for measures of hamstrings, quadriceps, plantarflexors, and ITB/TFL complex length, hip abductors strength, and foot pronation (ICCs from .85 to .97); moderate for measures of Q-angle, tibial torsion, hip external rotation strength, lateral retinacular tightness, and quality of movement during a step down task (ICCs from .67 to .79); and poor for femoral anteversion (ICC of .45). Standard error of measurement (SEM) for measures of muscle length ranged from 1.6 degrees to 4.3 degrees. SEM for Q-angle, tibial torsion, and femoral anteversion were 2.4 degrees, 2.9 degrees, and 4.5 degrees respectively. SEM for foot pronation was 1 mm. SEM for measures of muscle strength was 1.8 Kg for abduction and 2.4 Kg for external rotation. CONCLUSION: Several of the impairments associated with PFPS had sufficient reliability and low measurement error. Further investigation is needed to test if these impairment measurements are related to physical function and whether or not they are useful for decision-making.

Adolescent↗

PubMed1993

Football injuries in Australia at the élite level.

OBJECTIVE: To determine injury profiles for the élite level competitions of football played in Australia. DESIGN: Over the 1992 seasons, all injuries were prospectively recorded from 26 clubs in football competitions which included the Australian Football League (AFL), New South Wales Rugby League (NSWRL) and New South Wales Rugby Union (NSWRU). RESULTS: Some 2398 injuries were reported. In Australian Rules football, the most common injury was the hamstring tear (13%); this also accounted for the most time missed due to injury (16%). In rugby league and union, the most common injuries were head and facial lacerations (11% and 20%) followed by concussion (8% and 5%). The injuries accounting for most time missed were fractures and knee ligament injuries in the rugby codes. In Australian Rules football there were more lower limb muscle strain injuries, a high proportion of which were recurrences, with a significant incidence during training sessions. In the rugby codes, minor injuries to the head and neck were more common, particularly in forwards. While rugby league players suffered the most injuries, AFL injuries were on average more severe and consequently the total time missed through injury by players in these two codes was very similar. Rugby union had a significantly lower injury prevalence at the élite club competition level than rugby league or Australian Rules football. CONCLUSION: Injury rates in the élite football competitions are high, warranting ongoing analysis and further study in particular areas.

Anterior Cruciate Ligament Injuries↗

PubMed2004

Effect of dynamic stability on a step task in ACL deficient individuals.

Stair ascent and descent requires large knee motions and muscle forces that can be challenging for people with anterior cruciate ligament (ACL) deficiency. Movement and muscle activity patterns were compared in two groups of ACL deficient subjects and a group of uninjured subjects. The ACL deficient subjects were prospectively classified according to functional ability. "Copers" were defined as individuals with complete ACL rupture and no symptoms of knee instability and participated in high-level sports without difficulty. "Non-copers" were defined as ACL deficient individuals who had instability with low-level daily activities and were not able to participate in sports. Sagittal plane kinematic and kinetic data from the hip, knee and ankle and electromyographic data from the vastus lateralis, lateral hamstring, medial gastrocnemius, and soleus were collected as subjects stepped up and over a 26 cm high step. Both coper and non-coper subjects had altered movement patterns as they controlled the rapid movement from step ascent to descent with their involved limbs. Only non-copers used significantly different movement patterns on their involved limb compared to controls after they had descended from the step and their involved side accepted the weight of the body. Classifying subjects by functional ability resulted in more pronounced differences in movement patterns between non-copers and copers. Copers moved more like uninjured subjects.

Adult↗

PubMed2005

Posterior mini-incision technique for hamstring anterior cruciate ligament reconstruction graft harvest.

PURPOSE: This study presents a new approach to hamstring graft harvest. The hypothesis tested was that this approach, the posterior mini-incision technique, would result in (1) consistent semitendinosus (ST) and gracilis (Gr) tendon identification, (2) consistent identification and sectioning of the accessory semitendinosus tendon, (3) virtual elimination of the risk of cutting hamstring grafts short, (4) excellent safety, and (5) a small anterior incision with excellent cosmesis. TYPE OF STUDY: Surgical technique. METHODS: Two-hundred three consecutive primary hamstring anterior cruciate ligament reconstructions were performed in skeletally mature patients using this technique. Of these, 185 were located and 175 were clinically evaluated. Follow-up was 24 to 113 months. Ninety patients completed a brief cosmesis questionnaire. Seven fresh-frozen knees were dissected. The locations of the ST and Gr tendons were identified in the popliteal fossa along a medial-to-lateral axis for purposes of incision placement. The location of the accessory ST was documented and the distance from the posterior incision to the popliteal artery was measured. RESULTS: There were no complications referable to graft harvest. No tendon was cut short. The posterior graft harvest mini-incision and the anterior tibial fixation/tibial tunnel mini-incisions were each usually about 1 inch in length. Cosmesis evaluation showed that 80% of patients thought their incisions looked better than the incisions of others they had seen who had had anterior cruciate ligament reconstruction. None thought them worse. Cosmesis was important to a majority of patients. CONCLUSIONS: The posterior mini-incision technique facilitated safe, rapid hamstring graft harvest and virtually eliminated the risk of cutting tendons short. Cosmesis was excellent, and was important to patients. LEVEL OF EVIDENCE: Level V.

Anterior Cruciate Ligament↗

PubMedDate not supplied

Rectus femoris transfer for children with cerebral palsy: long-term outcome.

The purpose of this study was to evaluate the long-term results of rectus femoris transfer in cerebral palsy children with stiff-knee gait. Thirty-eight affected limbs in 24 children were evaluated preoperatively and 1 year postoperatively by gait analysis, with 26 limbs in 18 patients having final study, averaging 4.6 years postoperatively. Functional ambulatory status was evaluated based on Hoffer's criteria on ambulation. There were statistically significant improvements of 9.8 degrees in maximum swing-phase knee flexion and 7.0 degrees in total range of knee motion at 1 year, with a small loss of knee extension in stance. At final gait analysis, the improvement in the swing-phase knee flexion was maintained, but improvement in total range of knee motion was decreased. There were no significant changes in temporal parameters. Improvement in swing-phase knee flexion and foot clearance after rectus femoris transfer was associated with loss of knee extension at long-term follow-up. Hamstring lengthening in patients who develop excessive stance-phase knee flexion may be necessary.

Adolescent↗

PubMed2006

Influence of the psoas major and thigh muscularity on 100-m times in junior sprinters.

PURPOSE: This study aimed to investigate how the cross-sectional areas (CSA) of the quadriceps femoris (QF)3, hamstrings (Ham), and psoas major (PM) in junior sprinters are related to mean running velocity (MV100m) calculated from official records of 100-m races. METHODS: In 44 sprinters (22 boys and 22 girls) aged 14-17 yr, cross-sectional images were taken at the upper thigh and midthigh and midway between the fourth and fifth lumbar vertebrae using magnetic resonance imaging. CSA of the three muscles located in both sides were analyzed. For each muscle, the mean values of the CSA of the right and left sides were calculated and used for regression analyses of the relationships between CSA variables and MV100m. RESULTS: Stepwise multiple-regression analyses produced prediction equations of MV100m with independent variables of QF CSA at the midthigh and PM-to-QF CSA ratio at the upper thigh for boys (R = 0.38) and PM-to-QF CSA ratio at the midthigh for girls (R = 0.33). In the regression model for boys, QF CSA at the midthigh had a negative regression coefficient. CONCLUSION: For junior sprinters of both genders, the higher development of PM relative to QF, rather than absolute muscle size, is a factor in achieving a better performance in 100-m race performance.

Acceleration↗

PubMed2003

Magnetic resonance imaging findings after rectus femoris transfer surgery.

We describe the magnetic resonance (MR) imaging appearance of the knee flexor and extensor tendons after bilateral rectus femoris transfer and hamstring lengthening surgery in five patients (10 limbs) with cerebral palsy. Three-dimensional models of the path of the transferred tendon were constructed in all cases. MR images of the transferred and lengthened tendons were examined and compared with images from ten non-surgical subjects. The models showed that the path of the transferred rectus femoris tendon had a marked angular deviation near the transfer site in all cases. MR imaging demonstrated irregular areas of low signal intensity near the transferred rectus femoris and around the hamstrings in all subjects. Eight of the ten post-surgical limbs showed evidence of fluid near or around the transferred or lengthened tendons. This was not observed in the non-surgical subjects. Thus, MR imaging of patients with cerebral palsy after rectus femoris transfer and hamstring-lengthening surgery shows evidence of signal intensity and contour changes, even several years after surgery.

Adolescent↗

PubMed1996

The effect of tourniquet use on postoperative strength recovery after arthroscopic meniscectomy.

The purpose of this prospective study was to determine the effect of pneumatic tourniquet use during arthroscopic meniscectomy on postoperative recovery of quadriceps and hamstring strength. Thirty-four patients with no ligamentous instability underwent arthroscopic meniscectomy after random assignment to the tourniquet or no tourniquet group. Tourniquet pressure was determined with a nomogram that considered thigh circumference and systolic blood pressure at time of induction. Quadriceps and hamstring strengths were tested preoperatively and at 1 week and 4 weeks postoperatively on a Biodex isokinetic dynamometer and expressed as a percentage of the uninvolved side. No significant differences in quadriceps or hamstring strength were noted between groups at any time periods. The findings of this study indicate that recovery of quadriceps and hamstring strength after arthroscopic meniscectomy is not adversely affected by tourniquet use if tourniquet times and pressures are carefully controlled.

Adolescent↗

PubMedDate not supplied

A study of thyrotropin-releasing hormone for the treatment of spinal muscular atrophy: a preliminary report.

OBJECTIVE: To determine whether thyrotropin-releasing hormone (TRH) can increase muscle strength in children with spinal muscular atrophy types 2 and 3. DESIGN: A randomized, double-blinded, controlled, 5-wk drug trial of six subjects and three controls. Subjects and controls ranged from 4 to 8 yr of age and were randomly assigned to treatment and placebo groups in a ratio of 2:1. TRH (protirelin) or placebo was delivered intravenously through percutaneous intravenous catheters at a dose of 0.1 mg/kg (in 50 ml of normal saline) for a total of 29 days. Patients were evaluated using electromyography and handheld dynamometry of the deltoids, biceps, triceps, wrist extensors, hip flexors, quadriceps, hamstrings, and grip strength before and immediately after 5 wk of treatment. A unidirectional t test was used to compare mean values. RESULTS: Dynamometry improved significantly only for the six treated subjects (P < 0.02). Peroneal nerve conduction velocities were significantly faster in the treatment group (paired t test, P = 0.036). The parents of the treated children also provided anecdotal evidence of improvements in function. Improvements lasted 6-12 mo. CONCLUSIONS: TRH may be a useful treatment for spinal muscular atrophy. A larger, crossover design group comparison study is warranted.

Action Potentials↗