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[Surgical treatment of severe postburn flexion contractures of the hand].

The authors discuss the surgical tactics in multiple burn contractures of the palmar surface of the hand from experience in the treatment of 45 patients. The operation is conducted in one stage, with the manipulations performed in a definite order, which makes it much easier. The operation consists in correction of adduction of the thumb and the region of flexion contractures of the metacarpophalangeal articulations, palmar syndactyly, flexion contractures of the fingers, and contractions of the palm. Plastics with trapeziform grafts in combination of the palm. Plastics with trapeziform grafts in combination with free skin grafting makes it possible to correct all contractures in one stage and restore the function of the hand.

Burns↗

[Contractures and growth disturbances in the hip and pelvis as the cause of "idiopathic scoliosis". Biomechanical considerations].

Author's own observations on etiology of "idiopathic scoliosis" in children and adolescents are presented. Abduction or flexion-abduction contracture of the hip, mainly right one, is the chief cause of "idiopathic scoliosis". Scoliosis is the final deformity in the chain of malformations commencing in newborns and infants, known as "contracture syndrome". This condition is described by many authors, Mau and Green-Griffin were the first ones. Adduction contracture of the left hip leads to secondary dysplasia of this joint. Coexisting abduction contracture of the right hip is usually neglected. Insufficient adduction in the right hip in extension causes functional elongation of the right extremity and oblique positioning of the pelvis, thus initiating left hand side lumbar, thoraco-lumbar or lumbo-sacral scoliosis. As the next step thoracic scoliosis develops. Early and late clinical and radiographic symptoms are presented, prophylactics and treatment is discussed.

Adolescent↗

Limb contractures in progressive neuromuscular disease and the role of stretching, orthotics, and surgery.

Contractures are exceedingly common impairments in selected progressive NMD conditions, particularly those with excessive fibrosis and fatty infiltration into muscle (i.e., dystrophic myopathies) and more severe NMD conditions, resulting in significant weakness and wheel-chair reliance, such as SMA. Less than antigravity strength produces an inability to achieve full active range of motion. Static positioning of limbs (generally in flexion) and lack of weight bearing results in fixed contractures. This article has reviewed the prevalence and distribution of contractures in specific NMD conditions. Aggressive rehabilitation strategies, including stretching, positioning, splinting, upright weight bearing, and orthopaedic surgical management may help minimize the degree of disability in NMD patients with contractures.

Activities of Daily Living↗

Congenital cutaneous defects as complications in surviving co-twins. Aplasia cutis congenita and neonatal volkmann ischemic contracture of the forearm.

BACKGROUND: During twin pregnancies, several complications may result in the death of a co-twin depending on the date of death. We describe herein 2 infant survivors of monozygotic twin pairs with 2 distinct possible complications: a aplasia cutis congenita and Volkmann ischemic contracture. OBSERVATIONS: One infant had extensive aplasia cutis congenita with an associated monozygotic co-twin who died at 3 months of gestation, and the other child had a localized arm defect due to Volkmann ischemic contracture and brain damage, with a co-twin who died at approximately 6 weeks of gestation. CONCLUSIONS: Congenital cutaneous defects may result in the death of a co-twin. The most common of these defects is aplasia cutis congenita associated with a fetus papyraceus or a dead fetus related to ischemic/thrombotic events in the placenta and fetus. Volkmann ischemic contracture is rare in the newborn but can cause neonatal cutaneous defects. The cause of Volkmann ischemic contracture in newborns is unknown; however, our second observation suggests the possible role of a dead fetus.

Compartment Syndromes↗

van den Ende-Gupta syndrome of blepharophimosis, arachnodactyly, and congenital contractures: clinical delineation and recurrence in brothers.

We describe two Hispanic brothers born to unrelated parents with van den Ende-Gupta syndrome (VDEGS), a distinctive combination of characteristic dysmorphic features, skeletal abnormalities, and cerebellar hyperplasia. This syndrome was previously delineated by van den Ende et al. [1992: Am J Med Genet 42:467-469] and Gupta et al. [1995: J Med Genet 32:809-812], with additional reports by Phadke et al. [1998: Am J Med Genet 77:16-18] and Bistritzer et al. [1993: Clin Genet 44:15-19]. This is the fifth report of VDEGS, which is characterized by blepharophimosis, narrow nose with hypoplastic alae nasi, hypoplastic maxilla, everted lower lip, slender and elongated hands and feet, arachnodactyly, self-limiting joint contractures, and distinctive skeletal findings. This report of affected siblings, and a previous report of double second cousins born to consanguineous parents [Bistritzer et al. [1993: Clin Genet 44:15-19]], suggests autosomal recessive inheritance. This brings to eight, the total number of reported cases, derived from six families, three of which are consanguineous. It is important to distinguish VDEGS from Marden-Walker syndrome (MWS) since both syndromes include blepharophimosis, arachnodactyly, and congenital contractures. Both syndromes are inherited in an autosomal recessive fashion, but VDEGS lacks severe mental retardation, serious brain malformations, microcephaly, failure to thrive, and severe joint limitation, which are consistently present in MWS. Of particular importance, MWS may be associated with cerebellar malformations such as Dandy-Walker malformation, while the brothers reported herein with VDEGS both demonstrated distinctive cerebellar enlargement, a new finding for this disorder. While, congenital contractures with arachnodactyly are features commonly seen in several other delineated syndromes, such as congenital contractural arachnodactyly (CCA) syndrome, characteristic facial features (blepharophimosis, narrow nose with ocular hypertelorism, prominent ears, and everted lower lip), distinguish VDEGS from other syndromes associated with CCA, including CCA.

Blepharophimosis↗

Silicone breast implants: the role of immune system on capsular contracture formation.

We evaluated the role of the immune system in the pathogenesis of the periprosthetic capsular contracture, the most frequently occurring complication following the implant of silicone prostheses. Peripheral blood samples from 22 patients with silicone-gel-filled implants were examined. In all cases a capsule was felt by palpation, and it was classified according to the Baker scale. Ten patients (group 1) had a Baker 2 contracture, and 12 (group 2) had severe contracture rated 3 and 4. The cells positive to antigens CD3, CD4, CD8, HLA-DR, CD19, CD25, CD57, CD16, and CD14, and the cytotoxic activity of the lymphocytes on target cells K562 were assessed by cytofluorimetric analysis. At time 0 there were no statistically significant differences between patients and normal subjects, nor between the two groups. At 48 h, the group 2 patients had a number/mm3 of cells CD57 + significantly higher than both group 1 and control group (P < .05). In group 1 patients, the cytotoxic activity was similar to that of normal subjects, whereas in group 2 it was significantly increased, in respect to both the controls (P < .05) and group 1 (P < .001). In all groups, the contact of the lymphocytes with the silicone extract did not modify either the antigen expression or the lymphocyte functional activity. On the basis of these results we hypothesize the involvement of the immune system in the formation of the capsular contracture around the prosthesis.

Adult↗

Paradoxical effect of ischemic preconditioning on ischemic contracture? NMR studies of energy metabolism and intracellular pH in the rat heart.

Using the blood-perfused rat heart, we have previously shown that although ischemic preconditioning (PC) and cardioplegia (CP) afforded similar protection against post-ischemic contractile dysfunction this effect was not additive even though PC accelerated whereas CP delayed ischemic contracture. Using NMR we examined the effects of these interventions on pHi and ATP metabolism during global ischemia. Isolated rat hearts (n = 6/group) with an intraventricular balloon were aerobically perfused with buffer, subjected to zero flow ischemia (37 degrees C) for 35 min and reperfused for 40 min. The groups were: (1) controls without protection, (2) PC (2 cycles), and (3) St Thomas' cardioplegia, prior to test ischemia. PC accelerated whereas CP delayed ischemic contracture (P < 0.05 v controls). Yet, after 40 min reperfusion, both interventions produced substantial improvements in the recovery of LVDP (P < 0.05 v controls). During 35 min ischemia, the decline of ATP was delayed by CP but accelerated by PC (P < 0.05 v controls). The pHi fell steeply in controls to a plateau of 5.9 after 14 min ischemia. PC had no effect on the rate of fall of pHi but reduced its extent (P < 0.05). CP delayed the onset of the decline in pHi (P < 0.05) but, once initiated, there was no effect on the rate of decline to a plateau. Thus, despite protecting post-ischemic contractile function, PC accelerated ischemic contracture and the depletion of ATP, but substantially reduced intracellular acidosis. In contrast, CP slowed ischemic contracture and the depletion of ATP; it also delayed the onset of acidosis.

Animals↗

Calcium induced contracture stimulates Na,K-pump rate in isolated sheep cardiac Purkinje fibers.

By keeping intracellular Na+ (aiNa) low, the Na,K-pump can prevent Ca2+ overload of cardiomyocytes. We therefore examined whether Ca2+ stimulates Na,K-pump activity in sheep cardiac Purkinje fibers. By removing Ca2+, Mg2+ and K+, the fibers depolarized and aiNa rose to 70 mM. After addition of 6 mM Mg2+ and lowering extracellular Na2+ to 29 mM, 30mM Rb+ was added, and over 10-15 min aiNa recovered to 3-7 mM. Two load-recovery cycles were conducted in 10 fibers. During one of the cycles Ca2+ (0.1-1.0 mM) was added before Rb+, causing a contracture. During recovery aiNa fell faster during Ca2+ contracture than in control cycles. Between 30 and 20 mM the rates were -10.0+/-1.6 and -5.4+/-0.6 mM/min, respectively (P<0.05). In Ca2+-exposed fibers tension fell almost parallel with aiNa. Na, K-pump reactivation caused membrane potential (Vm) to hyperpolarize transiently to -70 mV. Ca2+ did not affect membrane conductance. For a given aiNa during reactivation, Vm was more negative during Ca2+ contracture and depolarized faster (P<0.05). Intracellular pH (pHi) fell from 7.11+/-0.05 to 6.92+/-0.08 (n.s.) during control load-recovery cycles and was 6.83+/-0.14 at the end of the Ca2+ cycles. ATP content of the fibers did not change significantly through two complete load-recovery cycles, but creatine phosphate (CrP) fell by about 40%. By fitting the data to a model incorporating the Hill equation we show that during Ca2+-induced contracture maximum Na,K-pump rate (Vmax) was increased by about 40% and aiNa that causes 50% pump activation (k0.5) was lowered from 21. 2+/-1.6 to 15.5+/-1.4 mM.

Adenosine Triphosphate↗

Do independent processes control the activation and inactivation of potassium contracture tension in rat skeletal muscle?

Potassium (K+) contracture tension, measured in small bundles of rat soleus muscle fibers during maintained depolarization, increases to a peak value and then decays either to the baseline or to a pedestal level. We have tested the hypothesis that the rise and fall of tension are determined by independent activation and inactivation processes. If the "Independence" hypothesis is correct, tension during the decay of K+ contractures should equal tension predicted from the product of the activation and inactivation parameters determined from the same K+ contractures. Both the measured and predicted tensions decayed to a pedestal level that was increased in amplitude in the presence of perchlorate ions. However, the measured tensions in normal solutions and in the presence of perchlorate were three to five times smaller than the predicted tensions. This result indicates that the activation and inactivation of processes controlling the rise and decay of K+ contracture tension are not independent.

Animals↗

Caffeine contractures in denervated frog muscle.

Caffeine contracture tension, effect of caffeine on the resting membrane potential, and caffeine influx in normal and denervated frog sartorius muscle have been investigated. Peak caffeine contracture tension is increased after denervation at all caffeine concentrations. The percentage increases in tension are highest for lower caffeine concentrations. The caffeine concentration required for half maximum tension is decreased from about 3.6 mM in control muscles to 2.6 mM in denervated muscles. Caffeine at 3.5 mM produces a depolarization of about 6 mV in control muscles and 16mV in denervated muscles. The large contracture tensions observed in denervated muscles are not due to the greater depolarization produced by the drug in denervated muscles since innervated muscles depolarized to the same level by external K+ do not enhance caffeine contracture tension. Both control and denervated muscles are highly permeable to caffeine. The increases in sarcoplasmic reticulum development ( Moscatello et al. 1965) and calcium content ( Picken and Kirby 1976) promoted by denervation may explain the larger tension elicited by caffeine in denervated muscles.

Animals↗

Effects of cAMP and forskolin on caffeine-induced contractures and myofilament Ca-sensitivity in saponin-treated rat ventricular trabeculae.

Trabeculae from the right ventricle of rat were chemically 'skinned' with saponin (50 micrograms ml-1 for 30 min). Caffeine (10 mM) induced a transient contracture as a consequence of Ca(2+)-release from the sarcoplasmic reticulum and subsequent activation of the myofilaments. The amplitude of the caffeine contracture was used as an index of the Ca(2+)-content of the sarcoplasmic reticulum. cAMP (0.1-10 microM) markedly potentiated the caffeine-induced response under standardized conditions. This was interpreted as a cAMP-induced increase in Ca2+ accumulation by the sarcoplasmic reticulum during the Ca2+ loading period before the application of caffeine. After removal of cAMP, the amplitude of the regularly evoked contractures slowly declined towards standard levels. The characteristic effects of cAMP on the caffeine contracture were mimicked by addition of forskolin (10(-6) M), a substance known to stimulate cAMP production by adenylate cyclase. The results suggest that a significant quantity of functional adenylate cyclase persists after saponin treatment. In these preparations cAMP had no effect on the apparent Ca(2+)-sensitivity of the myofilaments. If the preparations were exposed briefly to saponin, cAMP caused a decrease in the apparent Ca2+ sensitivity of the contractile proteins. However, further exposure to saponin, or to Triton X-100, caused a marked increase in maximum Ca(2+)-activated force (Cmax). It was concluded that 'briefly' saponin-treated preparations, exhibiting a reduction in Ca2+ sensitivity in response to cAMP, are not uniformly permeable to the bathing solution.

Actin Cytoskeleton↗

Comparison of effects of several inhalation anaesthetics on caffeine-induced contractures of normal and malignant hyperthermic skeletal muscle.

We have compared the combined effects of halothane, enflurane, isoflurane and methoxyflurane on caffeine-induced contractures of normal and malignant hyperthermia susceptible (MHS) skeletal muscle fascicles. We have found that caffeine contractures without and with the addition of any of these four anaesthetics are higher in MHS than in normal muscle. The differences between the normal and MHS muscle are about the same for all drug combinations. For all four anaesthetics the degree of increase of the contracture is about the same in the normal as in the MHS muscle. For both the MHS and the normal muscle the caffeine contractures are from greatest to least: halothane greater than isoflurane greater than enflurane greater than methoxyflurane. Examination of the relationships among the caffeine specific concentrations in the presence of the various anaesthetics shows significant differences for the comparisons of halothane with the other three anaesthetics but, for the most part, the comparisons among methoxyflurane, enflurane and isoflurane are not meaningful statistically.

Anesthesia, Inhalation↗

Does the surface structure of implants have an impact on the formation of a capsular contracture?

BACKGROUND: The formation of a fibrous capsule around a silicone breast implant is part of a physiologic foreign body reaction after breast augmentation. In contrast, the formation of a capsular contracture is a local complication of unknown cause. This study aimed to discover whether the surface structure of the implant (textured vs smooth) has any impact on the formation of a capsular contracture. METHODS: This prospective study included 48 female patients with unilateral capsular fibrosis grades 1 to 4 in Baker's clinical scaling system. Of these patients, 14 received implants with a textured surface (Mentor), and 34 received implants with a smooth surface (Mentor). The implants all were placed in a submuscular position by the same experienced plastic surgeon. The clinical data were assessed using standardized patient questionnaires. For histologic diagnosis, operatively excised capsular tissue was examined. Preoperatively, venous blood samples for determining serum hyaluronan concentrations were taken from the patients. The control group consisted of 20 patients without capsular fibrosis. RESULTS: The separate analysis of clinical data for the patients with textured and those with smooth-surfaced breast implants showed a slightly reduced degree of symptoms for the patients with textured silicone breast implants, as compared with those who had smooth-surfaced implants. The histologic assessment of the fibrosis showed a symmetric distribution for Wilflingseder scores 1 to 3 (29% each), whereas 13% of the capsular tissues could be assigned to Wilflingseder score 4. In contrast, the histologic assessment of the patients with smooth-surfaced implants predominantly showed a Wilflingseder score of 3 (65%). The serologic investigations via enzyme-linked immunoassay (ELISA) showed serum hyaluronan concentrations of 10 to 57 ng/ml (25.0 +/- 11.7 ng/ml). Therefore, no statistically significant differences in terms of serum hyaluronan levels could be determined between the two groups of patients. In comparison with the control group, the patients with implants showed elevated serum hyaluronan levels (p < 0.05). CONCLUSIONS: The histologic examination and serum hyaluronan concentration analysis showed no statistically significant difference between smooth-surfaced and textured implants (Mentor) with respect to the development of capsular contracture. On the other hand, the severity of capsular contracture showed a positive linear correlation with the degree of local inflammatory reactions, which were independent of the implant surface.

Adult↗

Na(+)-Ca2+ exchange induces low Na+ contracture in frog skeletal muscle fibers after partial inhibition of sarcoplasmic reticulum Ca(2+)-ATPase.

Contractile responses due to reduction in external sodium concentration ([Na+]o) were investigated in twitch skeletal muscle fibers of frog semitendinosus. Experiments were conducted after partial inhibition of sarcoplasmic reticulum Ca(2+)-ATPase by cyclopiazonic acid (CPA). In the absence of CPA, Na+ withdrawal failed to produce any change in resting tension. In the presence of CPA (2-10 microM), [Na+]o reduction induced a transient contracture without a significant change in the resting membrane potential. The amplitude of the contracture displayed a step dependence on [Na+]o, was increased by K(+)-free medium and was prevented in Ca(2+)-free medium. This contracture was inhibited by various blockers of the Na(+)-Ca2+ exchange but was little affected by inhibitors of sarcolemmal Ca(2+)-ATPase or mitochondria. When sarcoplasmic reticulum function was impaired, low-Na+ solutions caused no contracture. These results provide evidence that skeletal muscle fibers possess a functional Na(+)-Ca2+ exchange which can mediate sufficient Ca2+ entry to activate contraction by triggering Ca2+ release from sarcoplasmic reticulum when the sodium electrochemical gradient is reduced, and sarcoplasmic reticulum Ca(2+)-ATPase is partially inhibited. This indicates that when the sarcoplasmic reticulum Ca(2+)-ATPase is working (no CPA), Ca2+ fluxes produced by the exchanger are buffered by the sarcoplasmic reticulum. Thus the Na(+)-Ca2+ exchange may be one of the factors determining sarcoplasmic reticulum Ca2+ content and thence the magnitude of the release of Ca2+ from the sarcoplasmic reticulum.

Animals↗

The effect of myometrial contractures on uterine blood flow in the pregnant sheep at 114 to 140 days' gestation measured by the 4-aminoantipyrine equilibrium diffusion technique.

Uterine blood flow, between 114 and 140 days' gestation, measured by the 4-aminoantipyrine equilibrium diffusion technique, was significantly decreased from 1359.1 +/- 84.4 ml X min-1 (mean +/- SE) in the absence of contractures to 1147.4 +/- 71.8 ml X min-1 (mean +/- SE) during a contracture (p less than 0.01). Contractures reduced total uterine blood flow regardless of whether the ewe was standing or lying. These observations are in keeping with the suggestion that changes in total uterine blood flow may be an important mechanism responsible for the previously described temporal relationship between contractures and fetal neurophysiologic function.

Ampyrone↗

Effects of low extracellular calcium on cytosolic calcium and ischemic contracture.

We have shown that myocardial cytosolic calcium [Cai] rises during ischemia. Simultaneously membrane bound stores are depleted. The [Cai] rise precedes the onset of irreversible ischemic contracture. We found that a low extracellular calcium [Cao] (100 microM) perfusate decreased peak contracture pressure and delayed the time to onset and to peak of ischemic contracture in the isolated retroperfused rabbit heart subjected to 37 degrees C ischemia. [Cai] was measured with the intracellular [Cai] fluorescent indicator Fura-2 AM (10 microM) in a separate group. In the group exposed to 2.45 mM Ca2+ there was a significant rise (P less than 0.05) in [Cai] to above 50% of preischemic value after 30 min of ischemia. The [Cai] in the low [Cao] perfused group at 30 min of ischemia was 30% below the preischemic value. The peak of the [Cai] rise in the low [Cao] perfusate group was markedly attenuated and delayed to 40 min. Taken together it appears that low calcium perfusate (100 microM) prior to ischemia attenuates the ischemia-induced [Cai] rise, delays the onset, and decreases the force of contracture with irreversible ischemic injury.

Adenosine Triphosphate↗

Sodium-free contractures in frog myocardium damaged by catecholamines.

1. Sodium-free contractures were studied in myocardial strips from R. pipiens with extracellular sodium (Na+o) replaced by choline chloride and extracellular calcium (Ca2+o) varied with EGTA-buffer. Normal myocardium was compared with that damaged by adrenaline (ADR) or isoproterenol (ISO). 2. Frog myocardium, damaged by in vivo injections of catecholamines, remained relaxed when exposed to Na+/Ca2+-free solutions. Only in 2 out of 18 experiments were small contractures observed after several hours. 3. Addition of KCN to the Na+/Ca2+-free solution caused small contractures after several hours in 7 out of 10 experiments. 4. The time to maximum Na+-free contractures was correlated to Ca2+o in a dose-dependent manner, but not influenced by catecholamine-induced myocardial damage. 5. Cell injury in the frog heart after in vivo injections of catecholamines does not affect the sarcolemmal Na+/Ca2+-exchange and is not associated with passive leakage of Ca2+ from the extracellular to the intracellular space.

Animals↗

Biomechanical characterization and clinical implications of artificially induced crouch walking: Differences between pure iliopsoas, pure hamstrings and combination of iliopsoas and hamstrings contractures.

The purpose of this study was to characterize biomechanically three different crouch walking patterns, artificially induced in eight neurologically intact subjects and to compare them to selected cases of pathological crouch walking. The subjects were equipped with a lightweight mechanical exoskeleton with artificial muscles that acted in parallel with hamstrings and iliopsoas muscles. They walked at a speed of approximately 1m/s along the walkway under four experimental conditions: normal walking (NW), hamstrings contracture emulation (HAM), iliopsoas contracture emulation (IPS) and emulation of both hamstrings and iliopsoas contractures (IPSHAM). Reflective markers and force platform data were collected and ankle, knee and hip-joint angles, moments and powers were calculated. HAM and IPSHAM shifted ankle-angle rotation profiles into dorsiflexion during midstance compared to IPS and NW where ankle-angle trajectories were similar. HAM, IPS and IPSHAM shifted the knee angle of rotation profiles into flexion during stance, compared to NW. IPS and IPSHAM shifted hip angle of rotation profiles toward pronounced flexion while HAM shifted hip angle of rotation profile toward extension, compared to NW. HAM and IPSHAM significantly increased ankle moment during midstance, compared to IPS and NW where ankle moment profiles were similar. All experimental conditions exhibited similar behavior in the knee-moment profiles during midstance while IPS and IPSHAM knee-moment profiles exhibited significantly higher knee-extension moment during terminal stance and pre-swing. In the hip joint all experimental conditions exhibited similar shape of hip moment profiles throughout the gait cycle. HAM and IPS kinematic and kinetic patterns were qualitatively compared to two selected clinical cases, showing considerable similarity. This implies that distinct differences in kinematics and kinetics between HAM, IPS and IPSHAM may be clinically relevant in helping determine the relative contribution of hamstrings and iliopsoas muscles contractures to particular crouch walking.

Adult↗