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Background: Tractography of skeletal muscle can clearly reveal the 3-dimensional course of muscle fibers, and the procedure has great potential and could open new fields for diagnostic imaging. Studying this technique for clinical application, we noticed differences in the number of visualized tracts among volunteers and among muscles in the same volunteer. To comprehend why the number of visualized tracts varied so that we could acquire consistently high quality tractography of muscle fiber, we started to examine whether differences in individual parameters affected tractography visualization. Purpose: To determine whether there are gender- and age-specific differences that differentiate the muscles by gender and age in MR tractography of skeletal muscle fiber. Materials and Methods: We divided 33 healthy volunteers by gender and age among 3 groups, A (13 younger men, aged 20 to 36 years), B (11 younger women, 25 to 39 years), and C (9 older men, 50 to 69), and we obtained from each volunteer tractographs of 8 fibers, including the bilateral gastrocnemius medialis (GCM), gastrocnemius lateralis (GCL), soleus (SOL), and anterior tibialis (AT) muscles. We classified the fibers into 5 grades depending on the extent of visualized tracts and used Mann-Whitney U-test to compare scores by gender (Group A versus B) and age (Group A versus C). Results: Muscle tracts were significantly better visualized in women than men (median total visual score, 34 versus 24, P

SUMMARY The gait of seven hypotonic schizophrenic children aged between five and eight years was compared with that of seven normal children aged between seven and eight years. Electromyographic studies revealed that in schizophrenic children the tibialis anterior was ‘on’ during a significantly smaller proportion of the stance phase than in the age-matched controls, and that the quadriceps muscle was ‘on’ during a significantly smaller proportion of the swing phase than in the controls. In addition, the gait of the schizophrenic children tended to be broad-based and slow, consisting of smaller steps in a longer pace period. In general, the gait of the schizophrenic children resembled that of younger, inexperienced walkers. RESUME La demarche des enfants schizophrenes hypotoniques La demarche de sept schizophrenes hypotoniques âges de cing a huit ans a ete comparee a celle de sept enfants normaux de sept-huit ans. Les etudes electromyographiques ont montre que chez les schizophrenes, le jambier antetieur etait “en activite” durant une part significativement plus courte du temps portant que chez les controles de meme âge et que le muscle quadriceps etait “en activite” durant une part significativement plus courte du temps de balancement que chez les controles. De plus, la demarche des schizophrenes reposait sur une base elargie, etait lente, fait de pas plus courts et d'une periode plus longue que chez les controles. En general, la demarche des enfants schizophrenes ressemble a celle de jeunes marcheurs inexperimentes. ZUSAMMENFASSUNG Der Gang hypotoner, schizophrener Kinder Man hat den Gang von sieben hypotonen, schizophrenen Kindern im Alter von funf bis acht Jahren mit dem von sieben gesunden Kindern im Alter von sieben bis acht Jahren verglichen. Elektromyographische Untersuchungen ergaben, das bei den schizophrenen Kindern der M. anterior tibialis in der Haltephase und der M. quadriceps in der Schwungphase signifikant weniger aktiv war als bei den altersentsprechenden Kontrollkindern. Der Gang der schizophrenen Kinder tendierte dazu, breitflachig und langsam zu sein, mit kleineren Schritten in groseren Zeitabstanden, als bei den Kontrollen. Im allgemeinen ahnelte der Gang schizophrener Kinder dem kleiner Kinder, die gerade laufen lernen. RESUMEN La marcha del nino hopotonico esquizofrenico Se comparo la marcha de siete ninos hipotonicos esquizofrenicos de cinco a ocho anos de edad con la de siete ninos normales de siete a ocho anos de edad. Los estudios electromiograficos mostraron que en los ninos esquizofrenicos el tibial anterior funcionaba durante una proporcion significativamente menor de la fase estatica que en el grupo correspondiente control y que el cuadriceps durante una proporcion menor de la fase de balanceo con respecto a los controles. Ademas la marcha de los ninos esquizofrenicos tendia a un aumento de la base de sustentacion y era lenta, y consistia en pasos mas pequenos con un periodo de paso mas largo que el de los grupos control. En general, la marcha de los ninos esquizofrenicos se parecia a la de los caminadores jovenes sin experiencia.

Fifty-one children with cerebral palsy who were candidates for surgery for equinovarus deformities of the foot had their gait evaluated by means of foot-switches and electromyography to determine the contribution of the anterior tibialis and posterior tibialis muscles to the deformity. Seven EMG patterns and five foot-switch patterns were identified, but there was no correlation between the EMG and foot-switch patterns. Foot-switch data alone could not identify the deforming muscles or their patterns, so are not adequate for planning surgical correction of varus feet of children with cerebral palsy.

The relationship between patterns of strength and mobility was studied in 291 children with myelomeningocele, graded as community ambulators, partial (household) ambulators and nonambulators. Iliopsoas strength was found to be the best predictor of ambulation, with the quadriceps, anterior tibialis and glutei also contributing significantly. Grade 0 to 3 iliopsoas strength was always associated with partial or complete reliance on a wheelchair. No patient with grade 4 to 5 iliopsoas and quadriceps function relied completely on wheelchairs and the majority were community ambulators. Grade 4 to 5 gluteal and anterior tibialis function was associated with community ambulation, without aids or braces. Deterioration in mobility was most common in those with strong iliopsoas/quadriceps and grade 0 to 3 gluteus medius, and was not age-related.

The purpose of this study was to examine the effects of customized foot orthotics on lower extremity muscle activity and fatigue during march in combat boots. Four volunteers with normal foot and five volunteers with excessive pronation foot among soldiers on service were fitted with foot orthotics. The electromyography signal from activity of low extremity muscles were collected with surface electromyography device during walking on the treadmill. The walk on the treadmill was performed with a speed of 4.5 km/h. The experiment design for reseach wes composed two experimentation. The first experiment was to examine the muscle activity of lower extremity between normal foot and excessive pronator foot during march. The second experiment was to examine the muscle activity of lower extremity between wearing orthotics and no wearing orthotics. These data were analyzed by the averaged integral EMG and the mean power frequency. The analyzed results were compared by independent T-test method and paired T-test method of SPSS(windows version 12.0). The result of the study were the muscle activity on pronator foot tend to increase during march but a statistically significant increase in muscle fatigue of vastus lateralis and fibularis longus. A statistically significant decrease in muscle activity of anterior tibialis and fibularis longus and fatigue occurred using the customized foot orthotics in volunteers with excessive pronation foot compared to volunteers with normal foot. Clinically, the application of orthotics for the soldiers with excessive pronation foot appears to delay muscle fatigue and prevent from variable foot injuries. This may contribute to enhancing fighting efficiency.

Purpose: We measured fractional anisotropy (FA) of calf muscles from diffusion tensor (DT) images from simultaneous scanning of bilateral calves and determined changes in values after unilateral exercise loading. Method: We obtained DT images of both calves of 10 healthy male volunteers and measured FA of the anterior tibialis, gastrocnemius, and soleus muscles. Two of the ten were subjected to loaded exercise in their right calves; we recorded FA values immediately after exercise and 24 hours, 72 hours, and 1 week later. Results: At rest, the mean FA values of the 20 calves were 0.63±0.02 in the anterior tibialis, 0.56±0.05 in the gastrocnemius, and 0.57±0.04 in the soleus muscles. The differences were statistically significant (P

Loss of muscle mass and strength is a common symptom in the elderly population. This is partly a result of the structural changes that occur during the aging process. We applied diffusion tensor magnetic resonance imaging (DTMRI) to determine if water diffusivity in skeletal muscle changes with age.Thirty-eight healthy men, ranging from 27 to 67 years of age, were recruited for this study. The total population was grouped by age (Youngmean age 46.4: n = 20; Oldor = mean age 46.4: n = 18) and body mass index (BMI; Normal25: n = 20; Overor =25: n = 18). The principal, second, and third eigenvalues (lambda(1)or = lambda(2)or = lambda(3)), and fractional anisotropy (FA), were calculated from the diffusion tensor of the soleus, lateral and medial gastrocnemius, and anterior tibialis (AT). Analyses included comparison of groups and linear regressions.The older adults showed a significant reduction in the eigenvalues of the plantar flexors ( approximately 7%, p.05) and FA of AT ( approximately 10%, p.05) from that of the younger adults. No age differences were observed in the FA of the plantar flexors or eigenvalues of AT. lambda(1) and lambda(2) had a linear dependence on age in the plantar flexors, whereas AT showed age dependence in lambda(3) and FA.We demonstrated that DTMRI is sensitive to age-related changes in muscle, and that the effects of aging differ between the plantar flexors and AT.

Background Pain is a disturbing non-motor feature of Parkinson's disease(PD), with a reported prevalence of 40–50%. We aimed to understand the differences in nociceptive flexion reflex (NFR) in PH patients with/without pain. Methods We included 22 PD patients (9 patients without pain, 13 patients with pain) and 28 age-and-gender matched controls (13 subjects reported no pain, 15 controls with pain). NFR was recorded while lying supine. Stimulation with 20ms train of four 0.5ms electrical pulses was given to sole of the foot, recordings were done over anterior tibialis (AT) and long head of biceps femoris (BFLH). Results The latency of NFR recorded over AT was similar between patients with PD and controls with pain, but BFLH latency was shorter in PD group (100.0 ± 42.2 ms vs 108.4 ± 32.8ms, p > 0,05). The NFR amplitude in PD patients with pain was higher compared to patients without pain and healthy subjects. Conclusion Our study showed that parameters of NFR differ between PD patients with and without pain and controls. The higher amplitudes and shorter latencies may suggest that pain may have a facilitatory role in the manifestation of NFR.

Knowledge of the various graft options available for reconstruction of the knee with multiple ligamentous injuriesis necessary for the surgeon and patient to make an informed decision. Allograft is frequently used for such reconstructions, because multiple grafts are often necessary. Allograft avoids the morbidity associated with autograft harvest, allows smaller incisions, and saves operative time. A concern with the use of allograft, however, is the small but serious risk of disease transmission, including viral and bacterial infections. Allograft is also expensive and its availability may be limited. Some patients may prefer reconstruction with autograft tissue. Bone-patellar tendon-bone autograft is strong, stiff, and allows bony fixation at both ends. Harvest complications, primarily anterior knee pain, are drawbacks to using this source. Hamstring tendon autograft harvest results in less donor-site morbidity and comparable strength to bone-patellar tendon-bone autograft when bundled. Quadriceps tendon autograft also has been used in knee reconstruction, offering a strong graft with less morbidity than bone-patellar tendon-bone autograft harvest. Quadriceps tendon harvest is technically challenging, however. Achilles tendon and anterior tibialis allografts, as well as both autograft/allograft patellar tendon, quadriceps tendon, and hamstring tendon can all be used to reconstruct the anterior cruciate ligament, posterior cruciate ligament, or collateral ligament complexes. Ultimately, the choice of graft is dependent on surgeon and patient preference, availability of graft sources, and the number of ligaments requiring reconstruction or augmentation.

Haemoglobin concentrations and tumour-pO(2) were evaluated pre-therapy in 30 patients with head and neck cancers. Anterior tibialis muscle-pO(2) was additionally measured in 16 of these patients. Tumour-pO(2) was lower in the most anaemic patients (P=0.032) and correlated with muscle-pO(2) (r=0.809, P0.001). These results suggest that haemoglobin concentration influences tumour-oxygenation.

Modification of abnormal gait was attempted in real-time using a surface electromyography-based protocol to teach recruitment of the anterior tibialis at the correct time in the gait cycle. Two children diagnosed with cerebral palsy were able to learn volitional control of the anterior tibialis as demonstrated by improved clearance of the toe on the swing phase of the gait and newly learned ability to recruit and relax the anterior tibialis. The children were able to walk with the new gait pattern and reproduce the old one at will. Implications for future research in this area are discussed.

Unexpected external perturbations of body equilibrium elicit compensatory postural reflexes. The reflex patterns change only minimally, even after repetitive perturbations. This study addressed the question of whether classical conditioning can alter the reflex patterns. In the first session 27 healthy subjects were tested when standing on an unexpectedly tilting platform. Electromyographic (EMG) activity from different leg muscles and the vertical ground forces, from which the centre of vertical pressure (CVP) was computed, were recorded. In a subsequent session subjects were tested using the classical conditioning paradigm with the tilting platform as the unconditioned stimulus (US) and a prior auditory signal as the conditioning stimulus (CS). The decay of the unconditioned response (UR) observed in the first session was similar and small in all subjects. During conditioning, 22% of the subjects established conditioned responses (CR) in all muscles recorded (strategy 1). UR amplitudes of the anterior tibialis (TA) decayed more than in the first session. The resulting CVP excursions were similar to those observed in US-alone trials. The remaining subjects exhibited CR only in the gastrocnemius muscle but developed a substantial decay of UR, resulting in very small CVP excursions (strategy 2). Our data suggest that processing of US-preceding conditioning stimulus leads to different strategies in the control of postural adjustment with assumed underlying associative and non-associative plastic processes.

The purpose of this research is to provide scientific training guides and the basis for preventing injuries in performing tango backward walk by comparing the effects the height and shape of a heel will have on leg muscles and determining the difference between skilled and unskilled dancers through EMG analysis according to different types of shoes Total eight female athletes were selected for this research. Four with six years of professional dancing experience and another four with one year of dance sports experience. Utilizing the EMG system, rectus femoris, biceps femoris, anterior tibialis, gastrocnemius were measured under different heights (0cm, 5cm, 7cm, 9cm) and shapes (flat, fine, wide) of a heel. Experiments were conducted calculating EMG peak value and muscle load ration under different types of shoes in order to analyze the EMG of leg muscles and Erector Spinae when performing tango backward walk. The result was as follows: 1. The EMG peak value of leg muscles showed significant difference under different heights of a heel in anterior tibialis(p

The objective of this study was to test myoelectrically controlled functional electrical stimulation of the same muscle (AutoMCS) on patients with either stroke or spinal cord injury. The paretic anterior tibialis (TA) muscle was stimulated with an amplitude controlled continuously by the volitional myoelectric signal from the same muscle. Surface electrodes were used and volitional myoelectric signals were extracted by analog/digital signal processing techniques. Isometric dorsiflexion torque of the foot was displayed on a screen and the subjects were asked to track a sinusoidal curve. Subjects with dropped foot, as a result of a stroke (CVA, n = 9) or spinal cord lesion (SCI, n = 4), performed tests without and then with AutoMCS applied to the muscle. Subjects were their own control and tracking tests without and with AutoMCS. Changes in torque range, tracking delay, and tracking control accuracy have been evaluated. A significant (p < 0.05) increase of dorsiflexion torque by AutoMCS was found. An immediate carryover effect was seen in one stroke subject. The analysis of the tracking control showed only little loss of controllability with the system. We conclude that for selected subjects this method can instantly increase the muscle force of the anterior tibialis without significantly compromising tracking control or tracking delay.

Objective:To identify integrated EMG (I-EMG) activity of 6 lower-extremity muscles during the 8 Star Excursion Balance Tests (SEBTs).Design and Setting:Repeated measures, laboratory setting.Subjects:10 healthy young adults.Interventions:The SEBTs require the subject to balance on the stance leg and maximally reach with the contralateral foot along each of 8 lines extending from a common axis at 45° intervals.Measures:I-EMG activity of the vastus medialis obliquus (VMO), vastus lateralis (VL), medial hamstring (MH), biceps femoris (BF), anterior tibialis (AT), and gas-trocnemius.Results:Significant differences were found in all muscles (P< .05) except the gastrocnemius (P= .08). VMO and VL activity tended to be greatest with anteriorly directed excursions, whereas the MH and BF activity were greatest with posteriorly directed excursions. AT activity was lowest with the lateral excursion.Conclusions:Performance of the different SEBTs results in different lower-extremity muscle-activation patterns.

PURPOSE The purpose of this work was to characterize magnetization transfer (MT) contrast of skeletal muscles in limb girdle muscular dystrophy (LGMD). METHOD The calf muscles of five LGMD patients and 10 normal volunteers were imaged with an off-resonance MT suppression pulse applied to T1-weighted images. MT suppression ratios were calculated for anterior tibialis, posterior tibialis, soleus, and gastrocnemius muscles in the LGMD and control groups. The relationship between MT of individual muscles and the duration of LGMD symptoms was determined. RESULTS Strong MT contrast was observed in normal calf muscles, with mean (+/-SD) suppression ratios ranging from 37.9% (+/-3.0) to 41.1% (+/-2.1). In diseased muscle, MT signal suppression ranged from 11 to 38%, demonstrating an inverse relationship between symptom duration and suppression ratios. MT contrast in the LGMD patients, as a reflection of muscle tissue integrity, was preserved in posterior or anterior tibialis, soleus, and gastrocnemius muscles, respectively. Suppression ratios were dramatically reduced in muscles with gross fatty infiltration but also were reduced in muscle tissues without visual evidence of fatty infiltration. CONCLUSION MT imaging provides a quantitative measure of pathologic changes occurring within the skeletal muscles of patients with LGMD relative to normal and may be useful in evaluating disease extent, progression, and response to new therapies as they become available.

OBJECTIVE: To compare the intramuscular pressure (IMP) of the tibialis anterior in healthy persons under several exercise conditions with the IMP diagnostic criteria in use for diagnosing chronic exertional compartment syndrome (CECS). DATA SOURCES: A search of MEDLINE for the period 1966 to March 2010 used the words "intramuscular," "intracompartment," "anterior compartment," and "anterior tibial compartment" linked with "pressure." Reference lists of relevant studies were searched for further articles. STUDY SELECTION: Articles published in English that tested IMP in the tibialis anterior in asymptomatic humans were included if they used no interventions before or during IMP testing. Studies were excluded if data were given as a percentage of IMP or if the data could not be extracted for the tibialis anterior compartment alone. From 515 articles identified, 38 studies met selection criteria DATA EXTRACTION: : Details of the studies included IMP measurement technique, timing of measurement (before, during, and/or after exercise), type and duration of exercise, the number of compartments measured, and participants' ages. Mean or median pressure was recorded in mm Hg. DIAGNOSTIC STANDARD: Criteria for the upper limit of normal pressure under different conditions were the Pedowitz criterion for preexercise IMP (15 mm Hg), the Puranen criterion for IMP during exercise (50 mm Hg), the Styf criterion for relaxation pressure (30-55 mm Hg), and the Pedowitz criteria for mean 1-minute postexercise and 5-minutes postexercise pressures (30 mm Hg and 50 mm Hg, respectively). MAIN RESULTS: Exercise was mostly treadmill walking/running (duration, 1.5-120 min) or ankle dorsiflexion (duration, 10 sec-20 min). Methods of measuring IMP varied from study to study. The lowest mean IMP was identified preexercise at rest (range, 0-20 mm Hg). Five of the 34 studies found a higher mean resting pressure than the criterion (15 mm Hg). Mean pressure during exercise (10 studies, 9 of running, with durations of 5-20 min) varied between 23 mm Hg and 66 mm Hg. Two of these studies found a higher mean peak pressure during exercise than the criterion (50 mm Hg). Mean relaxation IMP, measured in 9 studies, was approximately 25 mm Hg in the 1 treadmill study in which it was measured, whereas studies of dorsiflexion found a range of approximately 5 to 15 mm Hg. All the studies found lower mean relaxation IMP than the criterion (35-50 mm Hg). One of 11 studies and 1 of 10 studies found the mean postexercise IMP after 1 minute and 5 minutes to be above the criteria of 30 mm Hg and 20 mm Hg, respectively. CONCLUSIONS: The limits of anterior tibialis IMP before, during, and after exercise that are used as diagnostic criteria for CECS would include many asymptomatic persons. Intramuscular pressure values were not valid criteria for the presence of the syndrome.

The purpose of this study was to assess leg muscle quality and give a detailed description of leg muscle involvement in a series of Duchenne muscular dystrophy patients using quantitative MRI and strength measurements. Fatty infiltration, as well as total and contractile (not fatty infiltrated) cross sectional areas of various leg muscles were determined in 16 Duchenne patients and 11 controls (aged 8-15). To determine specific muscle strength, four leg muscle groups (quadriceps femoris, hamstrings, anterior tibialis and triceps surae) were measured and related to the amount of contractile tissue. In patients, the quadriceps femoris showed decreased total and contractile cross sectional area, attributable to muscle atrophy. The total, but not the contractile, cross sectional area of the triceps surae was increased in patients, corresponding to hypertrophy. Specific strength decreased in all four muscle groups of Duchenne patients, indicating reduced muscle quality. This suggests that muscle hypertrophy and fatty infiltration are two distinct pathological processes, differing between muscle groups. Additionally, the quality of remaining muscle fibers is severely reduced in the legs of Duchenne patients. The combination of quantitative MRI and quantitative muscle testing could be a valuable outcome parameter in longitudinal studies and in the follow-up of therapeutic effects.

Background The standard approach to lateral tibial plateau fractures involves elevation of the iliotibial band (IT) and anterior tibialis origin in continuity from Gerdy’s tubercle and metaphyseal flare. We describe an alternative approach to increase lateral plateau joint exposure and maintain iliotibial band insertion to Gerdy’s tubercle. Description of Technique The approach entails a partial tenotomy of the anterior half of the IT band leaving the posterior IT band insertion attached to Gerdy’s tubercle. Fracture lines around Gerdy’s tubercle are completed or the tubercle was osteotomized and externally rotated and the joint overdistracted, allowing direct visualization of the joint depression. Joint elevation, grafting, and internal fixation are performed through this window. Methods We retrospectively reviewed 76 patients (two groups), Schatzker Types I to II and IV to VI fractures (66 patients), between 1989 and 2005, and 10 patients, with 10 bicondylar posterior plateau fractures, from 2002 to 2010. All patients were followed a minimum of 12 months (average, 3.9 years; range, 12 months to 10 years). Ten patients, with posterior plateau fractures, received anterolateral plateau intraarticular osteotomy for exposure of centroposterior and posterolateral articular depression. Results Average knee ROM was 2° of flexion (range, −3° to 5°) to greater than 120° of flexion (range, 100°–145°). In 66 patients, average articular depression improved from 7.4 mm to 1 mm (range, 0–5 mm) and, in 10 posterior fractures, from 18 mm to 1 mm (range, 0–4.5 mm). Infection occurred in one of the 76 patients; acute débridement and intravenous antibiotics resulted in control of the infection. Conclusions This approach reliably increases direct visualization of the lateral plateau articular fractures and maintains IT band insertion. Articular osteotomy of the anterolateral plateau provides access to extensive posterior plateau fractures. Level of Evidence Level IV, retrospective study. See Guidelines for Authors for a complete description of levels of evidence.

Mitochondria are dynamic organelles capable of significant changes of their ultrastructural features according to the tissue-specific energy demands. In human biopsies of vastus lateralis and anterior tibialis muscles from young (25.0 ± 4.4 years), middle-aged (50.4 ± 7.5 years) and old (75.5±3.9 years) healthy volunteers, we carried out a morphometric study on subsarcolemmal and intermyofibrillar mitochondria to assess whether age-related alterations of the morphology of these organelles contribute to the muscle performance decay in aging. By computer-assisted methods, we measured: the average area (MAA), the longer diameter (Dmax) and the ratio perimeter to area (pleomorphic index: Plei) of mitochondria. No significant age-related ultrastructural differences were found either in subsarcolemmal or intermyofibrillar organelles. However, in middle-aged as well as in the old group of patients vs. the young one, MAA and Dmax showed a clear trend to decrease, while Plei showed a marked, age-related tendency to increase. Higher percentages of less pleomorphic organelles were found in the youngest group of patients and this was particularly evident in the subsarcolemmal mitochondrial population. In addition to reporting on discrete aspects of mitochondrial ultrastructure, MAA, Dmax and Plei are closely related to each other and provide a reliable index of the muscle mitochondria adaptive response to age. Thus, we interpret our results as indicating a substantial preservation of muscle mitochondrial ultrastructure during aging.

The patient was identified and the extremity marked in the preoperative holding area. He/she was brought into the operative suite and placed supine on the operating table. The patient was induced into general endotracheal anesthesia without difficulty. IV antibiotics were administered. All bony prominences of the patient were well padded and protected.

We used bovine tibiae and two-stranded human anterior tibialis tendon grafts to compare biomechanical properties of two tibial fixation devices, the Milagro Interference Screw (Milagro) and the Bio-Intrafix Soft Tissue Tibial Fixation System (Bio-Intrafix). A total of 24 constructs (12 with each type of fixation) underwent biomechanical testing with 12 matched constructs undergoing uniaxial loading to failure (rate of 1 mm/sec) and the other 12 matched constructs undergoing cyclic loading (10,000 cycles at 1 Hz with a loading range of 125 to 375 N). All constructs failed by slippage of one or both ends of the anterior tibialis graft past the fixation device. One of the six Bio-Intrafix specimens failed before 10,000 cycles; four of the six Milagro specimens failed before 10,000 cycles. Bio-Intrafix, which is designed for a four-stranded graft, provided superior fixation to a traditional bioabsorbable interference screw in a two-stranded soft tissue graft at one of the weakest links in anterior cruciate ligament reconstruction surgery.

Purpose: To compare the results and outcome of anterior cruciate ligament (ACL) reconstruction using autogenous hamstring tendon versus fresh-frozen allograft anterior tibialis tendon. Methods: A prospective randomized study was conducted from September 2002 to October 2006. We randomized 147 patients to undergo ACL reconstruction with either autogenous hamstring or fresh-frozen allograft anterior tibialis tendon. Of these patients, 102 (69%) completed a minimum of 2 years’ follow-up. There were 54 patients in the hamstring group (73% of those originally enrolled in the group) and 48 patients in the allograft group (66%). All patients underwent standardized subjective and objective evaluation with functional outcome assessments (International Knee Documentation Committee [IKDC]), and standardized radiographs were also obtained. Results: The mean age was 32.0 years for the autograft group and 33.3 years for the allograft group. There was no difference in stability between the 2 groups (P .05). The mean IKDC subjective score was 91.0 for the autograft group and 90.9 for the allograft group (P .05). The functional IKDC scores for the autograft group were normal in 46 patients (85%), nearly normal in 7 patients (13%), and severely abnormal in 1 patient. For the allograft group, the functional IKDC scores were normal in 43 patients (90%) and nearly normal in 5 (10%) (P .05). There were 4 reoperations in the allograft group and 3 reoperations in the autograft group. No patient underwent revision ACL surgery or planned to undergo revision surgery because of instability in either group during the study period despite the 1 patient in the autograft group with a pivot shift and a maximum manual KT measurement (MEDmetric, San Diego, CA) of 5 mm. Conclusions: The use of fresh-frozen anterior tibialis allograft (non-treated) for ACL reconstruction produced similar subjective and functional outcomes at 24 months’ minimal follow-up compared with patients undergoing ACL reconstruction with autograft hamstring tendon. Level of Evidence: Level II, prospective comparative study.

Double-bundle anterior cruciate ligament (ACL) reconstruction can be demanding and time consuming and requires twice as many implants, increasing both costs and possible complications. In this article, we present a new approach to double bundle ACL reconstruction: a biological fixation of the tibial side by means of a double tunnel and a U-shape passage of an anterior tibialis allograft, fixed into a double tunnel on the femoral condyle with 2 interference bioabsorbable screws. The technique is designed to combine 2 known procedures for the regular knee surgeon: the mono-tunnel technique and the medial-portal approach.

Anterior cruciate ligament (ACL) injury in the skeletally immature individual is being recognized with increasing frequency. Nonoperative treatment of ACL injuries in skeletally immature patients have not been favorable. Surgical treatment options for complete ACL tears include primary ligament repair, extraarticular tenodesis, transphyseal reconstruction, partial transphyseal reconstruction, and physeal-sparing reconstruction. The advantage of transphyseal reconstruction is placement of the graft tissue in an isometric position, which provides better results, according to the literature. The potential disadvantage is angular or limb-length discrepancy caused by physeal violation. Controversy exists in allograft selection about whether bone or soft tissue passes into physes. The use of standard tunnels provides reliable results, but carries the risk of iatrogenic growth disturbance from physeal injury. This article presents 4 cases of transphyseal ACL reconstruction using anterior tibialis allograft in skeletally immature patients that had satisfactory functional outcomes with no growth disturbances. This is the first report of transphyseal ACL reconstruction using anterior tibialis allograft in skeletally immature patients in the English-speaking literature. All patients underwent transphyseal ACL reconstruction using anterior tibialis tendon allograft. None of the patients had angular deformities. No early physeal arrest was measured between the preoperative and postoperative radiographs. At last follow-up, the results of the Lachman test were normal for 3 patients and nearly normal for 1 patient. All patients demonstrated full range of knee motion (comparing the reconstructed knee to the contralateral knee). The results of the pivot-shift test were normal for 3 patients and nearly normal for 1 patient. No patients reported giving way.

A cap-shaped coil is introduced as a superior design for inducing transcranial magnetic motor evoked potentials for spinal cord monitoring. Evaluation of the magnetic characteristics of the cap coil showed higher induced electrical fields at and below the depth of the cortical surface, compared to a 9-cm, butterfly-shaped coil. Twenty normal adults were stimulated with the cap coil and a 9-cm round coil in three positions. Compound muscle action potentials were recorded from the left and right abductor digiti minimi and anterior tibialis muscles. The cap coil induced potentials with higher intensities and lower variability between consecutive stimuli. The cap coil was also more able to simultaneously induce motor evoked potentials from the four muscles studied. This coil design should provide superior means of inducing transcranial magnetic motor evoked potentials in multiple muscles.

Purpose:The aim of this study was to investigate the effects of a maximal repeated-jumps task on force production, muscle activation and kinematics, and to determine if changes in performance were dependent on gender.Methods:Eleven male and nine female athletes performed continuous countermovement jumps for 60 s on a force platform while muscle activation was assessed using surface electromyography. Performances were videotaped and digitized (60 Hz). Data were averaged across three jumps in 10-s intervals from the initial jump to the final 10 s of the test.Results:No interaction between time and gender was evident for any variable; therefore, all results represent data collapsed across gender. Preactivation magnitude decreased across time periods for anterior tibialis (AT, P < .001), gastrocnemius (GAS, P < .001) and biceps femoris (BF, P = .03), but not for vastus lateralis (VL, P = .16). Muscle activation during ground contact did not change across time for BF; however, VL, G, and AT showed significant reductions (all P < .001). Peak force was reduced at 40 s compared with the initial jumps, and continued to be reduced at 50 and 60 s (all P < .05). The time from peak force to takeoff was greater at 50 and 60 s compared with the initial jumps (P < .05). Both knee fexion and ankle dorsifexion were reduced across time (both P < .001), whereas no change in relative hip angle was evident (P = .10). Absolute angle of the trunk increased with time (P < .001), whereas the absolute angle of the shank decreased (P < .001).Conclusions:In response to the fatiguing task, subjects reduced muscle activation and force production and altered jumping technique; however, these changes were not dependent on gender.

Assessing muscular activity during gait in CP persons could provide valuable information in prescribing appropriate treatment to reduce the consequences of cerebral palsy as well as limiting further complication in cerebral palsy children. The main goal of this study was explored working regularities of muscle pairs in children population to show dependencies and variation on gait parameters. Functional evaluation was carried out on 20 cerebral palsy patients. The research have been done by using the system EMG. A surface electrode picked up on the main groups of muscles of lower limbs: the Rectus Femoris, the Vastus Lateralis, the Medial Hamstrings, the Lateral Gastrocnemius, and the Anterior Tibialis. There were several phases to the signal approach such as: data acquisition, data pre-processing, data modeling, data analysis and interpretation. From the results seen that for each task subjects have different strategies for keeping balance during walk depending on the basic level of muscle contraction or antagonistic and synergistic contraction required for that activity.

Jump height is increased when performers are given external focus instructions, relative to an internal focus or no focus instructions (Wulf & Dufek, 2009; Wulf, Zachry, Granados, & Dufek, 2007). The purpose of present study was to examine possible underlying neurophysiological mechanisms of this effect by using electromyography (EMG). Participants performed a vertical jump-and-reach task under two conditions in a counterbalanced order: external focus (i.e., focus on the rungs of the measurement device) and internal focus (i.e., focus on the fingers with which the rungs were to be touched). EMG activity of various muscles (anterior tibialis, biceps femoris, vastus lateralis, rectus femoris, gastrocnemius) was measured during jumps. Jump height was greater with an external compared to an internal focus. While there were no differences in muscle onset times between attentional focus conditions, EMG activity was generally lower with an external focus. These results suggest that neuromuscular coordination is enhanced by an external focus of attention. The present findings add to the evidence that an external focus facilitates the production of effective and efficient movement patterns.

Andrews et. al. developed an indoor rowing system for paraplegia using functional electrical stimulation (FES), and presented that the system was safe and healthy for paraplegia. However, the system would be better if the following three terms are improved: Firstly, only quadriceps and hamstrings in both thighs are activated by FES. Secondly, in order to switch FES, it is required to push periodically manual on-off FES switches set on a handle bar at effective timing in every rowing cycle. That might lead to fail to operate switches. Thirdly, constant FES intensity is used, which causes early muscles fatigues and strong pains. This paper describes the following improvements for the system: Firstly, by using gastrocnemius in calf and anterior tibialis in shank in addition, rowing speed is raised. Secondly, switching FES on and off is automated, which avoid failure to operate switches. Thirdly, the intensity for FES is adjusted automatically, which lead to relieve early fatigues and pains.

Single fibres from the anterior tibialis muscles of frogs were used in paired difference experiments to investigate the long-term effect (up to 3.8 s) of tetanic stimulation on fibre stiffness during relaxation. The fibres were stretched from sarcomere lengths of 2.5 microns to 3.0 microns at constant velocities for periods ranging from 0.5 to 1.75 s. The first stretch of each pair took place when the fibres had not experienced a tetanus for at least 5 min. The second stretch took place 20-30 s after the first, but it was preceded by a tetanus (100 Hz stimulation applied for 190 ms; temperature, 23 degrees C). The force produced by the first stretch was subtracted from the force produced by the second to produce a paired difference. The fibres were held at the sarcomere length of 3.0 microns except for a brief period of time immediately prior to the stretches (1200 or 1450 ms). During those periods the fibres were shortened to 2.5 microns (250 ms) and then held at 2.5 microns, regardless of whether a tetanus was elicited, for either 950 or 1200 ms. The second stretch of each pair began either at the end of, or 250 ms after, the last stimulating pulse of the tetanus. At every velocity of stretch, the force produced by the fibres during the stretches was greater when the stretches were preceded by a tetanus than when they were not, and the additional force peaked at the conclusion of the stretches. The additional force, which was produced during the stretches following the tetani, declined for the remainder of the data acquisition period (up to 3 s) following the completion of stretches; it extrapolated to zero at 7-8 s after the completion of the stretches. The magnitude of the additional force was a non-linear direct function of the rate of stretch. Thixotropy or an increased stiffness to stretch was observed in all of the fibres following periods of quiescence.

Cross-sections (thickness 10 microns) of whole autopsied left and right anterior tibialis muscles of seven young previously healthy right-handed men (mean age 23 years, range 18-32 years) were prepared for light-microscope enzyme histochemistry. Muscle cross-sectional area and total number of fibres, mean fibre size (indirectly determined) and proportion of the different fibre types (type 1 and type 2 on basis of myofibrillar adenosine triphosphatase characteristics), in each muscle cross-section were determined. The analysis showed that the cross-sectional area of the left muscle was significantly larger (P less than 0.05), and the total number of fibres was significantly higher (P less than 0.05), than for the corresponding right muscle. There was no significant difference for the mean fibre size or the proportion of the two fibre types. The results imply that long-term asymmetrical low-level daily demands on muscles of the left and the right lower leg in right-handed individuals provide enough stimuli to induce an enlargement of the muscles on the left side, and that this enlargement is due to an increase in the number of muscle fibres (fibre hyperplasia). Calculations based on the data also explain why the underlying process of hyperplasia is difficult, or even impossible, to detect in standard muscle biopsies.

The Bridle procedure is a tritendon anastomosis between the posterior tibialis, anterior tibialis, and peroneus longus, combined with an Achilles tendon lengthening for treating equinus and equinovarus deformities. The technique avoids problems of tendon attachment to bone and tendon placement for balance. One hundred seven procedures were performed on patients with cerebral palsy with 74% excellent and good results overall. The average follow-up was 5 years 9 months. The procedure was also performed with mixed results, on smaller groups of patients with other neuromuscular diseases.

This unit details some of the key methods for setting up and testing DNA vaccines in animal models. The basic procedures are discussed, as well as alternative methods that have been developed over the past several years. The Basic Protocol gives step-by-step instructions for administering the DNA vaccine via intramuscular injection of the quadriceps muscle, while an alternate procedure details injection of the anterior tibialis.

Incomplete spinal cord injury (ISCI) frequently disrupts afferent and efferent neural pathways underlying co-requisite voluntary and involuntary muscle activation required for functional standing and walking. To understand involuntary postural control mechanisms necessary for standing, we compared eight individuals with ISCI to eight controls with no impairment. The aim of this study was to investigate anticipatory and reactive balance responses in individuals with ISCI. The ability to adapt to changes in balance conditions was assessed by monitoring automatic postural responses (APRs) during a series of expected and unexpected changes in perturbation direction (backward translation versus toes-up rotation). Both groups were able to modulate appropriately within one or two trials following an unexpected change in condition. Onset times of anterior tibialis and medial gastrocnemius (MG) were significantly slower in the ISCI group during expected and unexpected conditions. These findings demonstrate that persons with mild to moderate lower extremity sensorimotor deficits are able to generate and adapt APRs to a rapid and unexpected contextual change during a simple standing balance task.

A new high-resolution MRSI technique was used to measure extracellular lipids (EMCL), intracellular lipids (IMCL), and total muscle lipids (TML). The purpose of this study was to assess the feasibility and reproducibility of this new technique. This study also compared results obtained from small regions of interest (ROIs) vs. a summation of a large ROI of voxels representing the total soleus or anterior tibialis (TA) muscles. Eight volunteers were studied with the use of a conventional single-slice MR spectroscopic imaging (MRSI) sequence run with the following parameters: TR = 145.9 ms, FOV = 16 cm, slice thickness = 1 cm, and 64 × 64 phase encodes. EMCL, IMCL, and TML values from the small ROIs proved to be reproducible (coefficient of variation (CV) = 7.8–13.8% for soleus, and 8.2–18% for TA). EMCL, IMCL, and TML values from the larger soleus ROI proved to be reproducible (CV = 7.3–16.1%), whereas the larger TA ROIs were less reproducible. The small and larger soleus ROIs produced statistically equivalent measures of EMCL and TML per unit area. However, the small soleus and TA ROIs showed a trend toward yielding different IMCL contents as compared to the larger ROIs. This study demonstrates that high-resolution 1H MRSI of the calf muscle is feasible and can reproducibly measure EMCL, IMCL, and TML. Magn Reson Med 57:848–858, 2007. © 2007 Wiley-Liss, Inc.

A strange thing happened on the way to understanding periodic leg movements in sleep (PLMS). The striking PLMS patterns of repetitive, short activations of anterior tibialis on an electromyography often accompanied by brief electroencephalogram (EEG) arousal certainly seemed to be a potent source of sleep disruption. A periodic limb movement disorder characterized by PLMS and sleep-wake complaints is defined to recognize the presumed sleep-disrupting effects of PLMS and is reported to be a common cause of insomnia and daytime sleepiness. Thus, PLMS are more important as markers of disease and its severity than as disrupters of sleep. Periodic limb movement disorder is rare if it exists. Despite the multiple causes for the pathology producing PLMS, these movements remain an important, easily measured marker of the functioning of subcortical dopamine systems. As a motor sign, they provide both an objective basis for confirming suspected diagnoses and an objective marker of the degree of the dysfunction. This is particularly useful for restless legs syndrome.

We present a case of a patient with hernia of anterior tibialis who was treated operatively. Muscle herniation through a fascial defect is rare, which requires repair of fascial defects. We performed a simple closure of fascial defect. A fasciotomy was proceeded to complication of acute compartment syndrome developed after the operation. The sequelae as weakness of dorsiflexion of ankle and big toe were present.

Purpose: The purpose of this study was to evaluate the outcome of anterior cruciate ligament (ACL) reconstruction via anterior tibialis tendon allograft. Methods: We performed a retrospective review of 125 consecutive patients who underwent ACL reconstruction via an anterior tibialis tendon allograft. Of these patients, 69 were available for follow-up at a mean of 55 months (range, 42 to 74 months); their mean age was 31.7 years (range, 19 to 69 years). Clinical evaluation consisted of the Lysholm knee score, activity level assessment, and International Knee Documentation Committee assessment. Results: Of the 69 patients, 16 (23.1%) required revision ACL reconstruction for graft failure. In addition, 26 patients (37.7%) required repeat surgery, including 16 revision ACL reconstructions, 9 arthroscopic meniscal surgeries, and 1 total knee arthroplasty. The mean age of those patients in whom failure occurred was 22.8 years compared with 34 years in those in whom failure did not occur ( P = .0039). The failure/reoperation rate of those aged 25 years or under was 55% (17/31), as compared with 24% (9/38) in those aged over 25 years. The mean Lysholm knee score was 85.6 (range, 15 to 100), and the mean activity score was 4.36 (range, 0 to 9). Of the 52 patients who did not require revision ACL surgery, 86.2% rated their knee as normal or nearly normal. Conclusions: A reoperation rate of 38% after primary ACL surgery is high. We do not recommend the use of anterior tibialis allograft in young patients (aged ≤25 years) or those who participate frequently in level I ACL-dependent sports. Level of Evidence: Level IV, therapeutic case series.

An adaptive logic network (ALN) has been used for nonparametric identification of the system consisting of two peripheral nerves and two muscles in the freely moving cat. The aim of this identification was to design a rule-based control for a functional electrical stimulation (FES) of the cat's hind limb. We recorded from peripheral nerves and muscles while a chronic cat walked an a powered treadmill. We noticed a very reproducible firing in tibial and superficial peroneal nerves related to patterns of EMG activity in medial gastrocnemius (MC) and anterior tibialis (AT) muscles in the cat's hind limb with respect to a phase of the gait cycle (e.g. beginning stance, beginning swing). We succeeded to restore and predict EMG activity of MG and AT muscles from neural recordings after applying Adaptive Logic Networks (ALNs). ALN is a type of artificial neural network having a tree configuration and using a Boolean operations in its nodes. We supplied a training set consisting of coded recordings from nerves and muscles (20 cat's steps were sampled at 50 Hz) for supervised training. Applied encoding and training parameters resulted in a reasonably short training time and high correlation between an originai and predicted EMG signals. The variance accounted for (VAF) by the ALN prediction of the test data was 80% qualify- ing this technique as a good candidate for implementation in real-time FES control systems.

Background and purpose To determine the accuracy of a new actigraphy system for the measurement of periodic leg movements (PLMs). Continuous measurements of leg movements, made overnight, are essential to diagnose and monitor treatment for PLMs. We have developed the Actiwatch with Cambridge Neuro-Technology Ltd (Cambridge, UK) to detect leg movements consistent with PLMs, to record these movements from both feet over three consecutive nights and to report standard indices of PLMs. We describe three studies designed to validate this device. Patients and methods The Actiwatch was assessed on a bench model across a range of movement amplitudes. The level of agreement on individual movements between the Actiwatch and bilateral anterior tibialis electromyography (BATEMG) measures was assessed in 199 epochs from five patients with known PLMs. The ability of the Actiwatch to correctly identify patients with PLMs was assessed in a comparison with polysomnography (PSG) in 50 consecutive patients investigated in the sleep laboratory. Results The Actiwatch detected all mechanically generated movements (100% sensitivity and 100% specificity) on the bench test. On individual movements BATEMG measurement and the Actiwatch agreed on 94% of epochs. The sensitivity and specificity of the Actiwatch to detect leg movements in severe PLMs as defined by BATEMG (PLMI≥25) are high (100% sensitive and 97% specific). Our bilateral system gave better agreement with BATEMG than previous systems but the two measures are still not interchangeable. Conclusions EMG is only a surrogate measure of limb movement and indices measured in this way correlate poorly with symptoms. We have demonstrated that the Actiwatch faithfully records movement, which offers the potential to reassess the relationships between limb movement indices and symptoms. This which offers a convenient and economical alternative to PSG in the study of large populations to increase our understanding of the epidemiology and clinical significance of PLMs.

This study compared magnetic resonance imaging (MRI) and surface electromyography (EMG) to evaluate the effect of knee angle upon plantar flexion activity in the triceps surae muscles [medial & lateral gastrocnemius (MG, LG) and the soleus (SOL)]. Two weight & height matched groups performed identical protocols, twelve (6M, 6F) in the MRI group, twelve (8M, 4F) in the EMG group. Subjects plantar flexed dynamically for 2 min at 25% of 1-repetition maximum voluntary contraction (1-RM). Exercise was performed with the knee extended (0 degrees flexion), flexed (90 degrees ), and partially flexed (45 degrees ). In the MRI group spin-echo images were acquired before and immediately following each exercise session. T(2) times, calculated at rest and after exercise by fitting the echoes to a monoexponential decay pattern with a least-squares algorithm, were compared with EMG data. In the EMG group a bipolar electrode was used to collect samples were from the MG, LG, SOL, and anterior tibialis (TA) during exercise at each knee angle, MRI also examined the peroneus (PER). At 0 degrees flexion MRI demonstrated a significant post-exercise T(2) increase in the MG (p < or = 0.001), LG (p < or = 0.001), and PER (p < or = 0.01), with no T(2) change in the SOL or TA. At 90 degrees flexion there was a significant T(2) increase in the SOL (p < or = 0.001) with no significant T(2) change in the MG, LG, PER, or TA. At 45 degrees T(2) increased significantly in the SOL (p < or = 0.001) and LG (p < or = 0.05), but not the MG, PER, or TA. EMG produced similar results with the exception that there was significant activity in the TA during the relaxation cycle of the 90 degrees protocol. We conclude that: 1) Soleus activity is measurable by MRI; and 2) MRI and EMG produce similar results from different physiological sources, and are therefore complementary tools for evaluating muscle activity.

This work investigates the kinematic and electromyography (EMG) strategy used by the central nervous system (CNS) to keep equilibrium during anterior–posterior balance on seesaws with different degrees of instability. The movement of hip, knee, and ankle were reconstructed using a 3D motion-analysis system and the EMG activities of selected ankle, knee, and hip muscles were recorded. Balance was kept mainly at the ankle joint. The EMG patterns of the gastrocnemius and anterior tibialis alternated between agonist and antagonist bursts. The agonist burst started before the end of the lengthening phase and was prolonged until the end of the shortening phase. The EMG activities of the muscles crossing the knee and hip joints were characterized by a pattern of generalized co-activation. The movements at these two joints were very small, suggesting a neural or biomechanical constraint underlying the operations of the equilibrium control. Our results also indicate that the strategy to keep balance on the seesaw is qualitatively the same for the different levels of mechanical demands in terms of the seesaw's instability.

Purpose: To determine if passive positioning of the ankle influences the MR imaging appearance of ankle tendons and ligaments. Methods: A positioning device was used during imaging of 10 volunteers. Axial and coronal T1-weighted images were acquired in six positions of the ankle, and the appearance of the tendons and lateral ligaments was subjectively evaluated. Results: The peroneus longus (PL), peroneus brevis (PB), anterior tibialis (AT), extensor digitorum longus (EDL), and extensor hallucis longus (EHL) tendons were best visualized in 20° of plantarflexion and 20° of inversion (pConclusion: When there is clinical concern regarding pathology of a specific structure about the ankle, passive positioning may allow optimal evaluation.

Spin-lock imaging is a new magnetic resonance imaging (MRI) technique used to reflect the microstructural integrity of muscle. The purpose of this study was to characterize spin-lock contrast (SLC) of calf muscles in limb girdle muscular dystrophy (LGMD). The calf muscles of 5 patients with LGMD and 10 healthy volunteers were imaged with an off-resonance magnetic resonance (MR) spin-lock suppression pulse. Spin-lock suppression ratios were calculated for anterior tibialis, posterior tibialis, soleus, and gastrocnemius muscles. Clinical assessments of muscle strength were compared to the spin-lock suppression ratios in the LGMD group. Strong SLC was observed in healthy muscles, with mean (+/- SD) suppression ratios ranging from 51.2% (+/- 3.6%) to 56.3% (+/- 1.3%). In diseased muscle, spin-lock signal suppression was reduced by 8%-70%, demonstrating an inverse correlation between symptom duration and suppression ratios. Spin-lock contrast in the patients with LGMD, as a reflection of tissue integrity, was best preserved in posterior tibialis, anterior tibialis, soleus, and gastrocnemius muscles in descending order. Clinical assessments did a poorer job of differentiating than SLC did and were in poor agreement with spin-lock suppression ratios. Spin-lock MRI can quantify microstructural changes in LGMD and appears to provide information not obtainable from clinical evaluations. This suggests that this noninvasive technique may be useful in evaluating the extent, progression, and response to therapy of LGMD.

transmit-receive extremity RF coil; previous medical history and investigation indicated compartment syndrome was suspected in the anterior tibialis region. High resolution T1-weighted SPGR images were acquired prior to functional imaging. Mid-calf axial BOLD images were acquired using a Gradient Echo sequence with an EPI readout (∝=70o, TE/TR=35/250ms, FOV 24cm, 64x64 matrix). 3072 contiguous images were acquired over 12.8 minutes at a rate of 4 per second (4Hz). Data acquisition was performed prior to and immediately following 30 minutes of intense exercise. BOLD data obtained from muscle regions of interest (ROIs; soleus, gastrocnemius, anterior tibialis) were spatially aligned with anatomical slices and Fourier transformed into frequency spectra using in-house programs written in Matlab (The Mathworks, Natick MA).

Study Objectives: To evaluate unattended full polysomnography (PSG) recorded in the home by the DigiTrace Home Sleep System (DHSS) and to assess the ability to acquire, store and analyze polysomnographic data using the DHSS compared to standard paper PSG. Design: Part 1 used a prospective, cross-over design. Part 2 consisted of a prospective concurrent collection of polysomnographic data. Setting: Sleep Disorders Center in a university medical center. Participants: All adult patients who required standard clinical PSG as part of their clinical evaluation, regardless of suspected diagnosis, except patients requiring video recording for abnormal behaviors. Measurements and Results: The DHSS is a digital recording system with miniature preamplifiers and the capacity to record 18 channels of polysomnographic data, including 4 channels of EEG (C 3 -A 2 , C 4 -A 1 , C 3 -O 1 and C 4 -O 2 ), right and left EOG, two channels of chin EMG, ECG naso-oral airflow, respiratory effort (piezo crystal thoracic and abdominal belts and bilateral intercostal EMG), snore microphone, bilateral anterior tibialis EMG, and body-position sensor. In part 1, 77 DHSS home recordings were evaluated. No recordings were lost due to equipment failure and each parameter was scorable in greater than 95% of all epochs. Most of the subjective assessments by questionnaire following each study revealed no difference between the two testing situations. However, patients reported more sleep time and a better overall test experience in the lab. Assessments of sleep quality and morning alertness compared to usual were rated higher in the lab. After completing both studies, more patients preferred the lab study (p