OBJECTIVETo explore an early stage repair method for soft tissue defect of limbs of modern firearm wound, and to improve treating result.

METHODSDefects of the hind limbs of dogs were repaired with skin, muscle and myocutaneous flaps.

RESULTSWounds healed within 2 weeks in the experimental group except one that healed in 3 weeks because of infection. Limb function was close to normal. The treatment result was better in the experimental group than the control.

CONCLUSIONSSkin, muscle and myocutaneous flaps can cover soft tissue defect at an early stage, prevent and reduce infection, promote the healing and recovery of combined injury, reduce the time of treatment and disability rate.

Animals ; Debridement ; Dogs ; Hindlimb ; injuries ; Microsurgery ; Soft Tissue Injuries ; surgery ; Wound Healing ; Wounds, Gunshot ; surgery

Using computerized motion analysis techniques, kinematics of foot trajectories were quantitatively analyzed in twelve rats before and after dorsal spinal cord hemisection at the T6 level. Although overground locomotion in these animals returned to normal within four weeks, some kinematic variables during treadmill locomotion did not recover to pre-lesion level. Immediately following dorsal hemisection, amplitudes of both hindfeet horizontal and vertical movements were dramatically reduces. However, in three weeks, the amplitudes of horizontal movement(stride length) became significantly larger than of pre-lesion strides. On the other hand, amplitude of hindlimb vertical movement showed very little recovery. Forelimb-hindmill coordination was also disrupted initially but returned to normal within three weeks. The duration of hindlimb swing phase became significantly longer after sectioning and gradually recovered, but never to pre-lesion levels. Interestingly, amplitudes of forelimb vertical movement. which was depressed initially, became significantly largery three weeks after lesioning. A dramatic increase in the statistical variation of limb kinematics, which persisted even after motor recovery, is an important parameter for the evaluation of neural deficits in spinal cord injuries. Kinematic analysis is a sensitive technique for the detection of minor motor deficits following nerve injuries.
Animals ; Biomechanical Phenomena ; Extremities ; Foot ; Forelimb ; Hand ; Hindlimb ; Locomotion* ; Rats* ; Spinal Cord Injuries ; Spinal Cord*

PURPOSE: The purpose of this study was to determine the effect of preserving muscle length or excursion on the progression of myostatic contracture after tendon injury in a rabbit soleus tenotomy model. MATERIALS AND METHODS: Forty rabbits underwent tenotomy of the soleus muscles bilaterally and the tendons were managed according to the five experimental groups (N=40). Group A was a tendon-lengthening group maintaining a half of the excursion. In group B, maximal muscle length was maintained and in group C, resting muscle length was maintained. In group D, the tendon was allowed to undergo myostatic contracture and in group E, the tendon was partially transected and repaired. Four and eight weeks postoperatively, soleus muscles were harvested from each hindlimb and histomorphometric evaluations were performed to measure the connective tissue and fiber cross-sectional areas. Electrophysiologic studies were carried out to measure the compound muscle action potential to assess the number of functioning muscle fibers. RESULTS: The results showed that maximal muscle length preservation (Group B) was the most protective in preventing muscle contracture within 4 weeks of tenotomy, but this protective effect was gradually offset by prolonged immobilization, and 8 weeks after tenotomy, maintenance of excursion (Group A) was the most protective. CONCLUSION: These observations can be useful in the intraoperative evaluation of myostatic contracture in neglected tendon ruptures, and be applied to the management of acute tendon injuries to prevent myostatic contracture when immediate anatomical reconstruction cannot be performed.
Action Potentials ; Animals ; Connective Tissue ; Contracture* ; Hindlimb ; Immobilization ; Muscles* ; Rabbits ; Rupture ; Tendon Injuries ; Tendons ; Tenotomy

OBJECTIVETo explore the protective effects of two types of ischemic postconditioning (IP) on intestinal mucosa barrier in rabbits with crush injury of the hind limb.

METHODSThis study was conducted between August and December 2008 in the Department of Trauma Surgery, Daping Hospital, Third Military Medical University, Chongqing, China. The model of crush injury to the hind limb of rabbits was firstly developed by a 25 kg object with the right hind limbs fixed by wooden splints, and then two types of IP were established, including occluding/opening the common iliac artery and vein alternatively (traditional IP, IP A) and binding/loosening the proximum of the injured hind limb alternatively (modified IP, IP B). Thirty-six male New Zealand white rabbits were randomly divided into three groups: IP A group, IP B group and control group, with 12 rabbits in each group. The serum levels of diamine oxidase (DAO) and intestinal fatty acid-binding protein (I-FABP) were detected at 2, 6, 12 and 24 hours after injury. Pathological changes of ileum were examined at 24 hours after injury.

RESULTSThe serum levels of I-FABP at 2, 6, 12 and 24 hours after injury in both IP A and IP B groups had a significant decrease, compared with control group. DAO levels also showed the same change trend at 2 and 6 hours after injury, but showed no significant difference between two IP groups. No difference in pathological changes of ileum was found among the three groups.

CONCLUSIONSIP can protect intestinal mucosa barrier function on the model of hind limb crush injury in rabbits. Meanwhile the modified IP B shows the same protection as the traditional IP A, and is worth applying in clinic.

Amine Oxidase (Copper-Containing) ; metabolism ; Animals ; Hindlimb ; injuries ; Intestinal Mucosa ; metabolism ; Ischemic Postconditioning ; Male ; Rabbits

OBJECTIVETo study the relationship between muscle motor evoked potentials (MEP) and hindlimbs motor function in rabbits with spinal cord injury.

METHODSForty-five rabbits were randomly divided into 9 groups, including one control group and 8 injured groups (receiving Allen's injury of 0, 50, 75, 100, 125, 150, 175, 200, or 250 gcf). Hindlimb strength and muscle MEP were recorded at the 1st day and 4th week postoperatively. At 4 weeks after spinal section, the spinal cord tissue was sampled for histological examination with HE staining and immunohistochemistry with anti-NF antibody of the corticospinal tract fibers.

RESULTSDuring the operation, MEP showed an all-or-none pattern with significant correlations to postoperative optical density of NF and postoperative hindlimb motor function. The latency prolongation of the muscle MEP at the 4th week showed a linear correlation to the hindlimb Tarlov's score, whereas the MEP amplitude was not correlated to postoperative hindlimb motor function.

CONCLUSIONSThe all-or-none pattern of muscle MEP can be used to evaluate the severity of spinal cord injury.

Animals ; Evoked Potentials, Motor ; Hindlimb ; physiopathology ; Pyramidal Tracts ; physiopathology ; Rabbits ; Spinal Cord Injuries ; physiopathology

Amnion ; cytology ; Animals ; Brain Injuries ; therapy ; Cell Transplantation ; Cells, Cultured ; Female ; Hindlimb ; physiology ; Humans ; Rats ; Rats, Sprague-Dawley ; Transplantation, Heterologous

Skeletal muscle possesses plasticity and adaptability to external and internal physiological changes. Due to these characteristics, skeletal muscle shows dramatic changes depending on its response to stimuli such as physical activity, nutritional changes, disease status, and environmental changes. Modulation of the rate of protein synthesis/degradation plays an important role in atrophic responses. The purpose of this review is to describe different features of skeletal muscle adaptation with various models of deceased use. In this review, four models were addressed: immobilization, spinal cord transection, hindlimb unloading, and aging. Immobilization is a form of decreased use in which skeletal muscle shows electrical activity, tension development, and motion. These results differ by muscle group. Spinal cord transection was selected to simulate spinal cord injury. Similar to the immobilization model, dramatic atrophy occurs in addition to fiber type conversion in this model. Despite the fact that electromyography shows unremarkable changes in muscle after hindlimb unloading, decreased muscle mass and contractile force are observed. Lastly, aging significantly decreases the numbers of muscle fibers and motor units. Skeletal muscle responses to decreased use include decreased strength, decreased fiber numbers, and fiber type transformation. These four models demonstrated different changes in the skeletal muscle. This review elucidates the different skeletal muscle adaptations in these four decreased use animal models and encourages further studies.
Aging ; Atrophy ; Electromyography ; Hindlimb Suspension ; Immobilization ; Models, Animal ; Motor Activity ; Muscle, Skeletal* ; Plastics ; Rodentia* ; Spinal Cord Injuries

The neurotoxic effects of excitatory amino acids(EAAs) in the brain are well documented, but their toxicity in the spinal cord has not been thoroughly studied. Intraspinal microinjections of quisqualic acid(QA) were done to evaluate its neurotoxic effects on neurons in the adult rat spinal cord. Animals were divided into four groups based on times of post-QA injections, ranging from 7-49 days. Total volume injected in each group ranged from 0.3 to 2.0microL of QA and normal saline(vehicle) were injected in lower thoracic and upper lumbar spinal cord. Kinematic analysis of recovery process was performed using a computerized motion analysis system after intraspinal injection of QA and saline. Our results showed that unilateral injections of QA produced either unilateral or bilateral neuronal degenerations during the survival period. This was accompanied by an inflammatory reaction and initiation of pathological process leading to spinal cavitation in 23 of 25 animals. Segments affected by QA injections showed darkly stained, hypertrophied neuronal profiles, and an increased expression of glial fibrillary acidic protein(GFAP). Immunostaining for GFAP was especially intense in the areas of neuronal degeneration and around the border of spinal cavities. The kinematic analysis of locomotion in the right hindlimb showed a decrease in gait height(pre-injection level: 2.07+/-0.12cm) at post QA injection 1 week(1.53+/-0.09cm), but returned to pre-injection level at 5 weeks(1.83+/-0.15cm). There was no statistical difference in the gait distance before and after QA injections. Results of this study have shown that the intraspinal injection of QA may be a suitable model to study cellular events of EAA-induced neurotoxicity on spinal neurons and the pathological process of spinal cavitation following neuronal degeneration. Computerized motion analysis system was useful for detection of the neurological deficits from minor spinal cord injury.
Adult ; Animals ; Brain ; Gait ; Hindlimb ; Humans ; Injections, Spinal ; Locomotion* ; Microinjections ; Neurons ; Rats* ; Spinal Cord Injuries ; Spinal Cord* ; Syringomyelia*

OBJECTIVE: To observe the effect of curing-injury cataplasma on the expression of aquaporin protein 3 (AQP-3) in skeletal muscle of rat model with acute injury in soft tissues. METHODS: A total of 54 SD rats were randomly divided into 3 groups, and by using 10% sodium sulfide the depilating treatment was made in the thigh lateral of each left hind leg 1 day before modeling. The depilatory area in the control group was merely marked with striking range, not attacked for modeling. In the depilatory area of the modeling group, the blowing apparatus was used to attack the marked range to establish the model of soft tissue swelling with acute injury, to which none medication was given. In the drug treatment group, immediately after establishing the model of soft tissue swelling with acute injury, curing-injury cataplasma was scattered on the stricken area, and fixed with bandage. After the modeling, the rats were killed at 1 h, 6 h, 1 d, 3 d, 5 d, and 7 d, 3 rats in each group at each time point. In the marked area some tissue was taken, and the dry/wet proportion method was used to detect the water content in the skeletal muscle. Western blot and qPCR method were used for the AQP-3 protein and the level of gene expression. RESULTS: At the six time points, for the modeling and drug treatment groups, the water content of skeletal muscle was higher than that of the control group (P<0.05). At 3 d, 5 d and 7 d, the water content in the drug treatment group was lower than that of the modeling group (P<0.01); for the modeling and drug treatment groups, AQP-3 protein and the level of gene expression were higher than those of the control group. There was significant difference between the drug treatment group and the modeling group (P<0.01). CONCLUSION Curing-injury cataplasma can relieve soft tissue swelling with acute injury, and accelerate the repair process after the injury.
Animals ; Aquaporin 3 ; metabolism ; Drugs, Chinese Herbal ; therapeutic use ; Hindlimb ; injuries ; Male ; Muscle, Skeletal ; metabolism ; Rats ; Rats, Sprague-Dawley ; Soft Tissue Injuries ; drug therapy ; metabolism

OBJECTIVE: To investigate the change of nitric oxide (NO) level in local muscles induced by crushing hind-limbs in rats. METHODS: The rat experimental model of hind-limb crushing injury was established by crushing the hind limbs of rats with standard weight for 5 hours, thereafter releving the standard weight for another 5 hours. The rats were randomly divided into sham group, crushing group, crushing and injecting aminoguanidine (AG) group, crushing and injecting L-arginine (L-Arg) group. The NOS activity and NO level in local muscles and serum were spectrophotometrically measured, and iNOS and eNOS protein expressions in local muscles were examined by immunohistochemistry. The weight ratio of wet to dry (W/D) of local muscles was measured and the pathologic changes were observed. RESULTS: The crushing hind-limbs induced serious primary and secondary injuries of local muscles such as rupture and rhadomyolysis of skeletal muscular fibers, interstitial vascular congestion and edema, and marked increase in W/D. The expressions of eNOS and iNOS were upregulated in local muscle in crush group compared with sham group. The NOS activity and NO level in local muscles and serum significantly increased. There was positive relationship between NO level and W/D in local muscles. With the usage of AG and L-arg, the hind-limb injuries seemed alleviated and aggravated, respectively. CONCLUSION The crushing hind-limbs of rats elicited the upregulation of eNOS and iNOS protein expression, the enhancement of NOS activity and the excess production of NO, the latter of which was involved in the mediation of secondary pathological changes in local muscles.
Animals ; Disease Models, Animal ; Female ; Hindlimb/injuries* ; Immunohistochemistry ; Male ; Muscle, Skeletal/pathology* ; Nitric Oxide/blood* ; Nitric Oxide Synthase/metabolism* ; Rats ; Rats, Wistar ; Soft Tissue Injuries/pathology*