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1.
We investigated the effects of different rates and extents of lengthening on the affected nerves and muscles in callus distraction, in a rabbit tibial model. Electrophysiologic evaluations measuring the motor nerve conduction velocity of the peroneal and tibial nerves, and compound muscle action potentials of the anterior tibialis and gastrocnemius muscle were performed sequentially on rabbits whose left legs were lengthened at different rates and to different extents over a 5-month period after surgery. We found that neuropathies of the peroneal nerves developed earlier and were more severe than those of tibial nerves, especially when the rate of lengthening was over 2 mm per day, or when the extent of lengthening was over 20% of the leg length at a lengthening rate of 1 mm per day. When the nerve damage was mild, there was a slow recovery of nerve function with time. The anterior tibialis muscle exhibited earlier and more severe damage than the gastrocnemius muscle during lengthening, especially when the rate of lengthening was over 2 mm per day, or when the extent of lengthening was over 20% of leg length. Elevated serum creatine kinase levels also indicated muscle damage after lengthening, especially in cases of high lengthening rates and long extent of lengthening. We conclude that nerves and muscles may have the same optimal rate of lengthening as bones, (1 mm per day). However, the extent of lengthening still has a limit of 20% or less of the total leg length. Electrophysiologic evaluation measuring the motor nerve conduction velocity and compound muscle action potential can serve as a tool for early detection and for long-term monitoring of neurologic dysfunction.  相似文献   

2.
The functions of ipsilateral cutaneous reflexes were studied with short trains of stimuli presented pseudorandomly to the superficial peroneal (SP) and tibial nerves during human gait. Electromyograms (EMGs) of tibialis anterior (TA), soleus, lateral and medial gastrocnemius, vastus lateralis (VL), and biceps femoris (BF) muscle were recorded, together with ankle and knee joint angles. Net reflex EMG responses were quantified in each of the 16 parts of the step cycle according to a recently developed technique. After SP nerve stimulation, TA muscle showed a significant suppression during swing phase that was highly correlated to ankle plantarflexion. BF and VL muscles were both excited throughout swing and significantly correlated to knee flexion during early swing. Tibial nerve stimulation caused dorsiflexion during late stance, but plantarflexion during late swing. We argue that SP nerve reflexes are indicative of a stumbling corrective response to nonnoxious electrical stimulation in humans. The correlated kinematic responses after tibial nerve stimulation may allow smooth movement of the swing leg so as to prevent tripping during swing and to assist placing and weight acceptance at the beginning of stance.  相似文献   

3.
Terminolateral neurorrhaphies were used up to the beginning of this century. After that, they were no longer reported. We tested the efficacy of a new type of end-to-side neurorrhaphy. A group of 20 rats had the peroneal nerve sectioned, and the distal ending was sutured to the lateral face of the tibial nerve after removing a small epineural window. All experiments were made on the right side, the left one remaining untouched in half the animals of each group. The other half was denervated by sectioning and inverting the endings of the peroneal nerves. In this way, tibial cranial muscles were either normal or denervated on the left side and reinnervated through end-to-side neurorrhaphies on the right side. After 7.8 months, the animals were subjected to electrophysiologic tests, sacrificed, and the nerves and muscles were taken for histologic examination. A response of the tibial cranial muscle was obtained in 90 percent of the animals. The distal ending of the peroneal nerve showed an average of 861 nerve fibers. The average areas of the reinnervated tibial cranial muscles were (microns 2) 1617.81 for M2n (when the contralateral side was normal) and 1579.19 for M2d (when the contralateral was denervated). We conclude that the terminolateral neurorrhaphy is functional, conducting electrical stimuli and allowing the passage of axons from the lateral surface of a healthy nerve, to reconstitute the distal segment of a sectioned nerve. The absence of an incision on the axons of the donor nerve was no impediment to axonal regeneration or to the passage of electrical stimuli. The results demonstrate the possibility of using end-to-side and terminolateral neurorrhaphies for reconstituting neural lesions when only a distal end is available; the reinnervation can be obtained from the lateral face of a healthy nerve.  相似文献   

4.
We describe a medial midline portal between the tendons of extensor hallucis longus and tibialis anterior for arthroscopy of the ankle. We dissected 20 cadaver specimens to compare the risk of neurovascular injury using this approach with that of using standard arthroscopic portals. Compared with the anterocentral portal, the medial midline was a mean of 11.2 mm further from the nearest branch of the superficial peroneal nerve and 10.3 mm further from the dorsalis pedis artery. This portal allows good access to the joint surface and intra-articular structures and has a lower risk of injury to the dorsalis pedis artery, deep peroneal nerve or the medial branch of the superficial peroneal nerve.  相似文献   

5.
YD Gu  XM Cheng  DS Chen  GM Zhang  JG Xu  L Chen  LY Zhang  PQ Cai 《Canadian Metallurgical Quarterly》1998,102(6):1973-8; discussion 1979-80
Femoral nerve transfer to the muscular branches of the thenar and hypothenar muscles was performed to determine its protective effect on the hand intrinsic muscles. Seven cases of brachial plexus root avulsion treated from May of 1989 to October of 1991 were involved. The femoral nerve transfer to the muscular branches of the thenar and hypothenar muscles was done at the same stage of multiple neurotization. The muscular branches derived from the femoral nerve were isolated and coapted with the thenar muscle branch of the median nerve and the deep branch of the ulnar nerve. A groin flap was harvested simultaneously to form a skin-tube pedicle that covered the nerve bridge. At the second stage, when regeneration of the median and ulnar nerves was found to reach as far as the level of the wrist, the femoral nerve was divided and the muscular branches of the thenar and hypothenar muscles were anastomosed with the regenerated median and ulnar nerves. All the cases were followed up for more than 6 years. Six months after femoral nerve transfer, muscle power of the interosseous muscles and adductor pollicis recovered to MRC3, whereas that of the abductor pollicis brevis recovered to MRC1 to 2. Five cases underwent second-stage transfer. Four to five years of follow-up revealed that the muscle power of the interosseous muscles and adductor pollicis was MRC2 in one case, MRC1 in three cases, and MRC0 in one case. As for the donor area, muscle power of the quadriceps femoris reduced to M3 to 4 within 1 month after femoral nerve transfer and recovered to normal at 3 months. In conclusion, femoral nerve transfer to the muscular branches of the thenar and hypothenar muscles has some protective effect on the hand intrinsic muscles. The outcome of the second stage, however, is not satisfactory.  相似文献   

6.
In some patients, oversized calves lead to mental distress and avoidance of certain social activities. They hide their legs in pants and seek medical advice. If the thickness of the subcutaneous fat is normal and cannot be diminished by liposuction, the oversized calves are caused by pure muscle hypertrophy. Using the gastrocnemius for muscle flaps in covering knee defects does not impair the function of the patient's leg; therefore, resection of the total gastrocnemius muscle for aesthetic calf reduction was performed in 15 consecutive patients without any lasting impairment with stability or sports activities. The patient was placed in a prone position, and the muscles were bluntly freed and pulled through two incisions of 5-cm length in the hollow of the knee and above the Achilles tendon. The resected muscles weighed between 410 and 810 g each. In two patients, the sural nerve was stretched or cut during the operation. The consequent numbness of the lateral ankle and sole persisted for 9 and 13 months, respectively. All 15 patients were satisfied with the results; none complained of lack of stability or insecurity in walking; and all became active in sports or changed their dress habits.  相似文献   

7.
Examined, in 4 experiments using 59 cats, the effects of a differential conditioning paradigm on the deep peroneal motor nerve response. Results show that flexor nerve response increases were produced when the conditioned stimulus/stimuli (CS) was delivered to the whole tibial nerve or to the medial plantar branch. The responses to CS/unconditioned stimuli presentations on the superficial peroneal nerve increased, whereas responses to CS presentations on the tibial nerve remained unchanged. However, lack of extinction effects in the superficial peroneal data suggests that stimulation of the tibial nerve potentiated superficial peroneal evoked responses. Furthermore, responses evoked by stimulation of either nerve increased when paired trials were given on the tibial nerve. These data demonstrate that stimulation of the tibial nerve potentiates responses to superficial peroneal nerve stimulation but that superficial peroneal nerve stimulation has no effect on responses to CS presentations to the tibial nerve. (7 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

8.
A combination of fluorescent retrograde tracers and horseradish peroxidase (HRP) was used to compare the spinal distributions of motoneurons supplying shoulder muscles with attachments to the skull and cervical spinal cord that suggest a significant role in head movement. Two muscles, the rhomboideus and the levator scapulae, were innervated by multiple segmental nerve bundles that entered the muscles at different rostrocaudal locations. Motoneurons that were labelled retrogradely from rhomboideus nerve bundles formed a single, long column in the ventral horn from C4 to C6, lateral to previously studied motor nuclei supplying deep neck muscles. When different tracers were used to differentiate motoneurons supplying specific nerve bundles, discrete subnuclei could be identified that were organized in a rostrocaudal sequence corresponding to the rostrocaudal order of the nerve bundles. Levator scapulae motoneurons formed a second elongate column immediately lateral to the rhomboidues motor nucleus. Three other muscles, that trapezius, sternomastoideus, and cleidomastoideus, were supplied by cranial nerve XI. Labelled motoneurons from these muscles formed a single column from the spinomedullary junction to middle C6. Within this column, the three motor nuclei supplying the sternomastoideus, cleidomastoideus, and trapezius were laminated mediolaterally. Sternomastoideus and cleidomastoideus motoneurons were confined to upper cervical segments, whereas trapezius motoneurons were found from C1 to C6. In C1 and C6, the motoneuron column was located centrally in the gray matter, but, between C2 and C5, the column lay on the lateral wall of the ventral horn in a position dorsolateral to motor nuclei supplying the rhomboideus and the deeper neck muscles. The findings in this study suggest that descending and propriospinal systems responsible for coordinating head movement may have to descend as far caudally as C6 if they are to project onto muscles controlling the mobility of the lower neck.  相似文献   

9.
A study of the relationships of the temporomandibular joint disc and the lateral pterygoid, temporalis, and masseter muscles during the human fetal period and in the adult was conducted. The superior head of the lateral pterygoid muscle was seen to insert into the anteromedial two thirds of the temporomandibular joint disc. The fibers of the posterior one third of the temporalis muscle and fibers of the deep bundle of the masseter muscle were attached on the anterolateral one third of the disc. The attachment of these muscles to the disc was through the anterior extension of the disc, also known as the premeniscal or prediscal lamina. The possible functional role of these muscle attachments is discussed.  相似文献   

10.
The effects of denervated muscle and Schwann cells on collateral sprouting from peripheral nerve were studied in the peroneal and tibial nerves of 48 Sprague-Dawley rats. Three groups were prepared. In group MSW (muscle-Schwann cell-window), the peroneal nerves were transected 3 mm below the sciatic bifurcation. The proximal stumps were sealed in a blocked tube to prevent regeneration and the distal stumps were implanted into denervated muscle cells that were wrapped around the ipsilateral tibial nerve, which had a window of perineurium resected. Schwann cells from the ipsilateral sural nerve were implanted into the muscle. Group MS (muscle-Schwann cell) was similar to group MSW, except that the tibial nerve perineurium was kept intact. In group MW (muscle-window), the muscle was prepared without Schwann cells and the tibial nerve perineurium was windowed. S-100 immunostain was used to identify the Schwann cells surviving 1 week after transplantation. After 16 weeks of regeneration, horseradish peroxidase tracer was used to label motor neurons and sensory neurons reinnervating the peroneal nerve. Myelinated axons of the reinnervated peroneal nerves were quantified with the Bioquant OS/2 computer system (R&M Biometrics, Nashville, TN). A mean of 169 motor neurons in group MSW, 64 in group MW, and 26 in group MS reinnervated the peroneal nerve. In the dorsal root ganglion, the mean number of labeled sensory neurons was 1,283 in group MSW, 947 in group MS, and 615 in group MW. The mean number of myelinated axons in the reinnervated peroneal nerve was 1,659 in group MSW, 359 in group MS, and 348 in group MW. Reinnervated anterolateral compartment muscles in group MSW were significantly heavier than those in group MS or MW. This study demonstrates that the transplantation of denervated muscle and Schwann cells promotes motor and sensory nerve collateral sprouting through a perineurial window.  相似文献   

11.
Motoneurons innervating peroneal muscles in the cat leg (PB, PT and PL, respectively, for peroneus brevis, tertius and longus) were examined for their connections with afferents from these and other leg muscles and with cutaneous afferents. The aim was to investigate (1) whether inputs from nearby muscles and cutaneous areas are likely to assist or oppose the excitation elicited in peroneal motoneurons by PB contractions, and (2) whether reflex connectivity might allow distinction of alpha (i.e. motoneurons innervating skeletal muscle fibres) and beta (i.e. motoneurons innervating both skeletal and intrafusal muscle fibres) subgroups among PB and PT motoneurons. In the three peroneal pools, every motoneuron had excitatory monosynaptic connections with Ia afferents from each of the three peroneal muscles, and nearly every motoneuron received di- or trisynaptic excitation from low-threshold cutaneous afferents in sural or superficial peroneal nerves. Inputs from these sources might facilitate the contraction-induced positive feedback. In contrast, the patterns of short-latency synaptic connections with group I afferents from pretibial flexor and post-tibial extensor muscles were heterogeneous among peroneal motoneurons but did not point to any specific beta pattern.  相似文献   

12.
The authors describe a supernumerary muscle in each orbit of an elderly male subject. There appear to be no previous reports of this muscle; most reports of anomalies of extraocular muscles describe hypoplasia or aplasia. Thirty-five formalin-fixed cadavers assigned to medical students for dissection were studied. The orbits were dissected by a superior approach which involved removal of the orbital plate of the frontal bone and the superior orbital margin. A supernumerary extraocular muscle was seen in each orbit of one cadaver, located between the superior oblique and levator palpebrae superioris muscles. It originated on the inferior surface of the lesser wing of sphenoid bone and was inserted into the skin of the medial one-third of the upper eyelid. It was innervated by a branch from the superior division of the oculomotor nerve. The insertion of the muscle into the upper eyelid produced a crease running obliquely upwards and medially, from the junction of the medial one-third and lateral two-thirds of the lid margin, towards the medial part of the superior orbital fold. The authors suggest the name levator palpebrae superioris accessorius for this muscle in view of its topography and action as tested in the cadaver. The significance of the findings is discussed and the literature on the development of the muscles supplied by the oculomotor nerve is reviewed.  相似文献   

13.
The proprioceptive feedback associated with the performance of even quite simple movements is always generated by the whole set of muscles subjected to mechanical deformation (lengthening, shortening, contraction, etc.) during that particular movement. The question was addressed here as to how muscle spindle feedbacks arising from agonist and antagonist muscles may contribute to the coding of movement parameters such as the direction and velocity. For this purpose, the activity of single muscle spindle afferents located in the lateral peroneal nerve was analysed using the microneurographic technique, in human subjects performing repetitive voluntary movements, i.e., plantar/dorsal flexions of the ankle, at three different velocities (3, 4.5 and 6 degrees/s). The data obtained suggest that in humans, the direction of a slow movement may be specified on the basis of the spindle discharge rate, which is greater in the stretched than in the shortened muscle, and that the velocity of this movement might be correlated with the difference between the spindle activity occurring in the agonist and antagonist muscles. These neurophysiological data are in agreement with the results of previous psychophysical studies showing for example that a sensation of illusory movement can be elicited only when there exists an imbalance between the agonist versus antagonist vibration-induced Ia inputs. In addition, the greater the difference between the vibration frequencies applied to the two antagonist muscles, the higher the perceived movement velocity was found to be. All in all, joint movement perception seems to result from the co-processing by the central nervous system of the multiple spindle feedbacks originating from the whole set of muscles involved in the performance of a movement.  相似文献   

14.
Motor nerves have been claimed to contain and release immunoreactive insulin. We studied whether release of insulin or other non-acetylcholine substances is important for (1) the increase in glucose transport normally seen during motor nerve activated contraction, and (2) the increase in insulin sensitivity induced by contractions. Ad 1:Rat hindquarters were perfused and one sciatic nerve was stimulated during motor nerve end plate blockade (Pancuronium bromide, 33 micrograms ml-1). Muscle glucose transport (3-O-[14C]-methylglucose (3-O-MG) uptake, 3 mM) was identical (P > 0.05) in stimulated compared with nonstimulated white gastrocnemius, red gastrocnemius and soleus muscle. This was also true when, prior to end plate blockade, muscles had been stimulated to contract to increase insulin sensitivity. No immunoreactive insulin was found in venous perfusate. Ad 2: Rats had both sciatic nerves cut. One week later hindquarters were perfused and calf muscles of one leg were directly stimulated to contract. Subsequently, 3-O-MG uptake in muscle was determined with and without submaximal insulin (100 microU ml-1). In contrast to previous findings in innervated muscle, responses to insulin were identical (P > 0.05) with and without prior contractions. Conclusions: The increase in muscle glucose transport normally seen in response to motor nerve stimulation is related to the contraction process and not even partly mediated by release of insulin-like substances from the nerve. In contrast, release of a non-acetylcholine substance from the motor nerve may be involved in the exercise induced increase in insulin sensitivity.  相似文献   

15.
OBJECTIVE: To clarify, through electrophysiologic mapping and cadaveric dissection of the lateral foot, the previously published "proximal" and "distal" recording sites for tibial motor nerve conduction studies. DESIGN: Observational. SETTING: Electromyography laboratory; anatomy laboratory. PATIENTS OR OTHER PARTICIPANTS: Ten asymptomatic feet; eight cadaveric feet. MAIN OUTCOME MEASURES: (1) Amplitudes and onset latencies of compound muscle action potentials (CMAPs) recorded over a grid on the lateral foot that included the "proximal" and "distal" recording sites; (2) nerve supply and anatomic boundaries of the abductor digiti minimi pedis (ADMP) and nearby muscles, particularly as they relate to the above recording sites. RESULTS: (1) Relatively large CMAPs were recorded at and around the "proximal" and "distal" sites, with significantly shorter "proximal" latencies. (2) In all cadaveric feet, ADMP was innervated by only the inferior calcaneal nerve (ICN) and was located deep to the "proximal" site, with virtually no muscle fibers deep to the "distal" site. The flexor digiti minimi brevis (FDMB) was conspicuously located immediately deep to the "distal" site and was innervated by only the lateral plantar nerve (LPN). CONCLUSIONS: This study strongly suggests that the "proximal" site records predominantly from the ICN-innervated ADMP, whereas the "distal" site predominantly records from the LPN-innervated FDMB.  相似文献   

16.
1. The technique of glycogen depletion was used to determine whether regenerating motor axons reestablish the normal regionalization of motor units (MUs) in the cat medial gastrocnemius (MG) muscle, 2) whether the extent of clumping between MU fibers and/or type grouping of muscle fibers progressively increases with a decrease in reinnervated MU numbers, and 3) whether the pattern of innervation can explain why MUs fail to increase significantly in size when the cut nerve is sutured directly to the muscle, even when few axons make functional connections. 2. Distributions of MU fibers were analyzed in 5 normal and 14 reinnervated cat MG muscles 4.5-16 mo after sectioning of its nerve and suturing of the proximal end to the distal nerve sheaths (N-N suture) or directly to the muscle fascia (N-M suture). Muscle unit distributions were quantified according to location, territory size, density, and extent of clumping between fibers from the same MU. 3. Normal MU fibers were regionalized within five regions along the muscle's longitudinal and transverse axes. Reinnervated MUs were located within similar regions, indicating that regenerating axons follow the major proximal nerve branches to restore normal compartmentalization. 4. Muscle unit fibers were diffusely scattered within discrete MU territories in normal muscles. Territory size tended to increase with MU size, whereas density of muscle unit fibers within the territory decreased. 5. Territories increased with MU size after N-N suture but were smaller and showed little size variation after N-M suture. The extent of muscle unit fiber clumping was inversely related to the number of reinnervated MUs. On average, the extent of clumping was substantially higher in muscles reinnervated after N-M suture. These results indicate that distal nerve sheaths facilitate proximal axon branching, which establishes MU territory size. Once the territory is established, motor axons branch distally to increase MU size, which in turn compensates for reduced MU numbers. 6. Muscles reinnervated by < 80% of the MUs exhibited fiber type grouping of type I fibers, and on average the extent of clumping was substantially higher in muscles reinnervated after N-M suture. With less innervation, type grouping increased inversely with the number of reinnervated MUs. However, for a similar number of MUs, type I fiber type grouping was substantially higher in muscle reinnervated after N-M suture. Type grouping therefore reflects muscle unit fiber clumping under conditions where MU size increased (N-N suture) or MU territory size decreased (N-M suture).  相似文献   

17.
Muscular force in running turkeys: the economy of minimizing work   总被引:1,自引:0,他引:1  
During running, muscles and tendons must absorb and release mechanical work to maintain the cyclic movements of the body and limbs, while also providing enough force to support the weight of the body. Direct measurements of force and fiber length in the lateral gastrocnemius muscle of running turkeys revealed that the stretch and recoil of tendon and muscle springs supply mechanical work while active muscle fibers produce high forces. During level running, the active muscle shortens little and performs little work but provides the force necessary to support body weight economically. Running economy is improved by muscles that act as active struts rather than working machines.  相似文献   

18.
This study set out to examine in detail the distribution of axons of sympathetic non-noradrenergic neurons innervating the arterial bed in skeletal muscles of the forelimb and hindlimb of guinea-pigs. The distribution of non-noradrenergic axons with immunoreactivity to vasoactive intestinal peptide (VIP) was examined in limb muscles of different histochemical character. The immunohistochemical demonstration of myosin heavy chain from fast-twitch muscle, and the histochemical demonstration of adenosine triphosphatase and succinic dehydrogenase, were used to determine the muscle fibre profile of 6 different limb muscles. Muscles included the oxidative type I muscle fibre-rich accessory semimembranosus muscle, the predominantly glycolytic type II muscle fibre-rich cranial gracilis and biceps brachii muscles and the plantaris, gastrocnemius medial head and triceps brachii long head of mixed muscle fibre composition. The frequency with which the VIP-immunoreactive (VIP-IR) axons innervated intramuscular arterial vessels was compared between categories of muscles defined by their muscle fibre profile. This study demonstrated that the projection of non-noradrenergic sympathetic neurons to skeletal muscle vasculature was widespread in guinea-pig limb muscles, but that it was not uniform. VIP-IR axons were more likely to innervate the arterial vasculature of muscles with a high proportion of type I and/or oxidative muscle fibres than of muscles with a large proportion of type IIb muscle fibres. This relationship between the distribution of sympathetic non-noradrenergic axons and the metabolic characteristics of muscle suggests that these presumed vasodilator neurons have an important role in matching blood flow to the particular metabolic demands of different limb muscles.  相似文献   

19.
The purpose of this study was to investigate the functional interrelationship between synergistic muscle activities during low-level fatiguing contractions. Six human subjects performed static and dynamic contractions at an ankle joint angle of 110 degrees plantar flexion and within the range of 90-110 degrees (anatomic position = 90 degrees) under constant load (10% maximal voluntary contraction) for 210 min. Surface electromyogram records from lateral gastrocnemius (LG), medial gastrocnemius (MG), and soleus (Sol) muscles showed high and silent activities alternately in the three muscles and a complementary and alternate activity between muscles in the time course. In the second half of all exercise times, the number of changes in activity increased significantly (P < 0.05) in each muscle. The ratios of active to silent periods of electromyogram activity were significantly higher (P < 0.05) in MG (4.5 +/- 2.2) and Sol (4.3 +/- 2.8) than in the LG (0.4 +/- 0.1), but no significant differences were observed between MG and Sol. These results suggest that the relative activation of synergistic motor pools are not constant during a low-level fatiguing task.  相似文献   

20.
Three cases of total knee arthroplasty (TKA) covered with pedicle peroneal flaps are reported. One peroneal flap was performed after TKA to correct post-TKA skin necrosis. Two peroneal flaps were performed before TKA to replace previous traumatic scar formed around the knee. All three TKAs were successful after the procedure. The thickness, elasticity, appearance, and durability of the peroneal flaps were more suitable for the skin around the knee than the gastrocnemius muscle flap or the local fasciocutaneous flap. As the peroneal flap was elevated as a pedicle flap, freedom of transfer was good, microanastomosis was not necessary, and no donor sites were needed from the contralateral limb. Scar tissue around the knee can be effectively replaced by the pedicle peroneal flap before TKA.  相似文献   

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