The quality of Achilles tendon repair five to eight years after percutaneous tenotomy in the treatment of clubfoot: clinical and ultrasonographic findings.

AIMS: Our aim was to describe the mid-term appearances of the repair process of the Achilles tendon after tenotomy in children with a clubfoot treated using the Ponseti method. PATIENTS AND METHODS: A total of 15 children (ten boys, five girls) with idiopathic clubfoot were evaluated at a mean of 6.8 years (5.4 to 8.1) after complete percutaneous division of the Achilles tendon. The contour and subjective thickness of the tendon were recorded, and superficial defects and its strength were assessed clinically. The echogenicity, texture, thickness, peritendinous irregularities and potential for deformation of the tendon were evaluated by ultrasonography. RESULTS: The appearance of the Achilles tendon was slightly abnormal, with more thickening and less conspicuous contours than a normal tendon. Its strength was grossly normal, with no insufficiency of the triceps surae. Ultrasonographic findings revealed a mild fusiform thickening in 12 children (80%). The tissue at the site of the repair had a slightly hypoechoic, fibrillar quality with hyperechoic striation and the anterior contour was irregular and blurred. There was a focal narrowing within the healing tissue in two children. CONCLUSION: This mid-term evaluation of the ability of the Achilles tendon to repair after division suggests a combination of intrinsic and extrinsic mechanisms. There were minor abnormalities which did not appear to affect function. Cite this article: Bone Joint J 2017;99-B:139-44.

High-impact exercise in rats prior to and during suspension can prevent bone loss

High-impact exercise has been considered an important method for treating bone loss in osteopenic experimental models. In this study, we investigated the effects of osteopenia caused by inactivity in femora and tibiae of rats subjected to jump training using the rat tail suspension model. Eight-week-old female Wistar rats were divided into five groups (n=10 each group): jump training for 2 weeks before suspension and training during 3 weeks of suspension; jump training for 2 weeks before suspension; jump training only during suspension; suspension without any training; and a control group. The exercise protocol consisted of 20 jumps/day, 5 days/week, with a jump height of 40 cm. The bone mineral density of the femora and tibiae was measured by double energy X-ray absorptiometry and the same bones were evaluated by mechanical tests. Bone microarchitecture was evaluated by scanning electron microscopy. One-way ANOVA was used to compare groups. Significance was determined as P<0.05. Regarding bone mineral density, mechanical properties and bone microarchitecture, the beneficial effects were greater in the bones of animals subjected to pre-suspension training and subsequently to training during suspension, compared with the bones of animals subjected to pre-suspension training or to training during suspension. Our results indicate that a period of high impact exercise prior to tail suspension in rats can prevent the installation of osteopenia if there is also training during the tail suspension.

High-impact exercise in rats prior to and during suspension can prevent bone loss.

High-impact exercise has been considered an important method for treating bone loss in osteopenic experimental models. In this study, we investigated the effects of osteopenia caused by inactivity in femora and tibiae of rats subjected to jump training using the rat tail suspension model. Eight-week-old female Wistar rats were divided into five groups (n=10 each group): jump training for 2 weeks before suspension and training during 3 weeks of suspension; jump training for 2 weeks before suspension; jump training only during suspension; suspension without any training; and a control group. The exercise protocol consisted of 20 jumps/day, 5 days/week, with a jump height of 40 cm. The bone mineral density of the femora and tibiae was measured by double energy X-ray absorptiometry and the same bones were evaluated by mechanical tests. Bone microarchitecture was evaluated by scanning electron microscopy. One-way ANOVA was used to compare groups. Significance was determined as P<0.05. Regarding bone mineral density, mechanical properties and bone microarchitecture, the beneficial effects were greater in the bones of animals subjected to pre-suspension training and subsequently to training during suspension, compared with the bones of animals subjected to pre-suspension training or to training during suspension. Our results indicate that a period of high impact exercise prior to tail suspension in rats can prevent the installation of osteopenia if there is also training during the tail suspension.

The osteogenic effects of swimming, jumping, and vibration on the protection of bone quality from disuse bone loss.

We assessed and compared the effects of swimming, jumping, and vibration therapies on the prevention of bone loss because of unloading. Eighty Wistar rats were randomly divided into eight groups: S, permanent hind limb-suspended rats; CON, control rats; S + Swim, unloading interrupted by swimming exercise; S + C(Swim), suspension interrupted by regular weight-bearing with the same duration as in the S + Swim protocol; S + Jump, unloading interrupted by jumping exercise; S + C(Jump), suspension interrupted for regular weight-bearing as in the S + Jump group; S + Vibr, unloading interrupted by vibration; and S + C(Vibr), suspension with interruptions for regular weight-bearing with the same protocol as that used for the S + Vibr rats. At the end of the experiment, the bone mineral density, bone strength, histomorphometric parameters, and serum levels of the bone markers were analyzed. The hind limb-suspended rats exhibited bone quality loss. In contrast, the trained rats showed a significant increase in bone mass, bone strength, bone formation, and serum levels of bone markers compared with the respective controls. Although we did not find a significant difference among the three physical exercises, the osteogenic effect of vibration was slightly lower than that of swimming and jumping. Thus, all physical exercises were efficient in preventing bone loss because of unloading and preserving bone quality.

Pamidronate for the treatment of osteoporosis secondary to chronic cholestatic liver disease in Wistar rats

Osteoporosis is a major complication of chronic cholestatic liver disease (CCLD). We evaluated the efficacy of using disodium pamidronate (1.0 mg/kg body weight) for the prevention (Pr) or treatment (Tr) of cholestasis-induced osteoporosis in male Wistar rats: sham-operated (Sham = 12); bile duct-ligated (Bi = 15); bile duct-ligated animals previously treated with pamidronate before and 1 month after surgery (Pr = 9); bile duct-ligated animals treated with pamidronate 1 month after surgery (Tr = 9). Rats were sacrificed 8 weeks after surgery. Immunohistochemical expression of IGF-I and GH receptor was determined in the proximal growth plate cartilage of the left tibia. Histomorphometric analysis was performed in the right tibia and the right femur was used for biomechanical analysis. Bone material volume over tissue volume (BV/TV) was significantly affected by CCLD (Sham = 18.1 ± 3.2 vs Bi = 10.6 ± 2.2%) and pamidronate successfully increased bone volume. However, pamidronate administered in a preventive regimen presented no additional benefit on bone volume compared to secondary treatment (BV/TV: Pr = 39.4 ± 12.0; Tr = 41.2 ± 12.7%). Moreover, the force on the momentum of fracture was significantly reduced in Pr rats (Sham = 116.6 ± 23.0; Bi = 94.6 ± 33.8; Pr = 82.9 ± 22.8; Tr = 92.5 ± 29.5 N; P < 0.05, Sham vs Pr). Thus, CCLD had a significant impact on bone histomorphometric parameters and pamidronate was highly effective in increasing bone mass in CCLD; however, preventive therapy with pamidronate has no advantage regarding bone fragility.

Pamidronate for the treatment of osteoporosis secondary to chronic cholestatic liver disease in Wistar rats.

Osteoporosis is a major complication of chronic cholestatic liver disease (CCLD). We evaluated the efficacy of using disodium pamidronate (1.0 mg/kg body weight) for the prevention (Pr) or treatment (Tr) of cholestasis-induced osteoporosis in male Wistar rats: sham-operated (Sham = 12); bile duct-ligated (Bi = 15); bile duct-ligated animals previously treated with pamidronate before and 1 month after surgery (Pr = 9); bile duct-ligated animals treated with pamidronate 1 month after surgery (Tr = 9). Rats were sacrificed 8 weeks after surgery. Immunohistochemical expression of IGF-I and GH receptor was determined in the proximal growth plate cartilage of the left tibia. Histomorphometric analysis was performed in the right tibia and the right femur was used for biomechanical analysis. Bone material volume over tissue volume (BV/TV) was significantly affected by CCLD (Sham = 18.1 ± 3.2 vs Bi = 10.6 ± 2.2%) and pamidronate successfully increased bone volume. However, pamidronate administered in a preventive regimen presented no additional benefit on bone volume compared to secondary treatment (BV/TV: Pr = 39.4 ± 12.0; Tr = 41.2 ± 12.7%). Moreover, the force on the momentum of fracture was significantly reduced in Pr rats (Sham = 116.6 ± 23.0; Bi = 94.6 ± 33.8; Pr = 82.9 ± 22.8; Tr = 92.5 ± 29.5 N; P < 0.05, Sham vs Pr). Thus, CCLD had a significant impact on bone histomorphometric parameters and pamidronate was highly effective in increasing bone mass in CCLD; however, preventive therapy with pamidronate has no advantage regarding bone fragility.

Biomechanics and structural adaptations of the rat femur after hindlimb suspension and treadmill running

We microscopically and mechanically evaluated the femurs of rats subjected to hindlimb unloading (tail suspension) followed by treadmill training. Female Wistar rats were randomly divided into five groups containing 12-14 rats: control I (118 days old), control II (139 days old), suspended (tail suspension for 28 days), suspended-released (released for 21 days after 28 days of suspension), and suspended-trained (trained for 21 days after 28 days of suspension). We measured bone resistance by bending-compression mechanical tests of the entire proximal half of the femur and three-point bending tests of diaphyseal cortical bone. We determined bone microstructure by tetracycline labeling of trabecular and cortical bone. We found that tail suspension weakened bone (ultimate load = 86.3 ± 13.5 N, tenacity modulus = 0.027 ± 0.011 MPa·m vs ultimate load = 101.5 ± 10.5 N, tenacity modulus = 0.019 ± 0.006 MPa·m in control I animals). The tenacity modulus for suspended and released animals was 0.023 ± 0.010 MPa·m vs 0.046 ± 0.018 MPa·m for trained animals and 0.035 ± 0.010 MPa·m for control animals. These data indicate that normal activity and training resulted in recovered bone resistance, but suspended-released rats presented femoral head flattening and earlier closure of the growth plate. Microscopically, we found that suspension inhibited new bone subperiosteal and endosteal formation. The bone disuse atrophy secondary to hypoactivity in rats can be reversed by an early regime of exercising, which is more advantageous than ordinary cage activities alone.

Biomechanics and structural adaptations of the rat femur after hindlimb suspension and treadmill running.

We microscopically and mechanically evaluated the femurs of rats subjected to hindlimb unloading (tail suspension) followed by treadmill training. Female Wistar rats were randomly divided into five groups containing 12-14 rats: control I (118 days old), control II (139 days old), suspended (tail suspension for 28 days), suspended-released (released for 21 days after 28 days of suspension), and suspended-trained (trained for 21 days after 28 days of suspension). We measured bone resistance by bending-compression mechanical tests of the entire proximal half of the femur and three-point bending tests of diaphyseal cortical bone. We determined bone microstructure by tetracycline labeling of trabecular and cortical bone. We found that tail suspension weakened bone (ultimate load = 86.3 +/- 13.5 N, tenacity modulus = 0.027 +/- 0.011 MPa.m vs ultimate load = 101.5 +/- 10.5 N, tenacity modulus = 0.019 +/- 0.006 MPa.m in control I animals). The tenacity modulus for suspended and released animals was 0.023 +/- 0.010 MPa.m vs 0.046 +/- 0.018 MPa.m for trained animals and 0.035 +/- 0.010 MPa.m for control animals. These data indicate that normal activity and training resulted in recovered bone resistance, but suspended-released rats presented femoral head flattening and earlier closure of the growth plate. Microscopically, we found that suspension inhibited new bone subperiosteal and endosteal formation. The bone disuse atrophy secondary to hypoactivity in rats can be reversed by an early regime of exercising, which is more advantageous than ordinary cage activities alone.

Bovine bone screws: metrology and effects of chemical processing and ethylene oxide sterilization on bone surface and mechanical properties.

We assess the effects of chemical processing, ethylene oxide sterilization, and threading on bone surface and mechanical properties of bovine undecalcified bone screws. In addition, we evaluate the possibility of manufacturing bone screws with predefined dimensions. Scanning electronic microscopic images show that chemical processing and ethylene oxide treatment causes collagen fiber amalgamation on the bone surface. Processed screws hold higher ultimate loads under bending and torsion than the in natura bone group, with no change in pull-out strength between groups. Threading significantly reduces deformation and bone strength under torsion. Metrological data demonstrate the possibility of manufacturing bone screws with standardized dimensions.

Effect of treadmill exercise on lumbar vertebrae in ovariectomized rats: anthropometrical and mechanical analyses.

The purpose of this study was to examine the preventive effect of exercise on lumbar vertebrae in ovariectomized rats. Three-month-old female Wistar rats were divided into 3 groups: control group (A, n = 10); non-exercised ovariectomized group (B, n = 7) and exercised ovariectomized group (C, n = 7). The rats from group C were subjected to treadmill exercise (15 m/minute in the initial six weeks and 19 m/minute in the next six weeks, 1 hour/day, 4 days/week) for 12 weeks. At death, the fourth lumbar vertebrae were removed and an anthropometrical analysis by a paquimeter and a mechanical compression test by a universal test machine were performed. After 12 weeks, the ovariectomy decreased the superior-inferior vertebral height and the maximal braking load in group B compared to group A, while the exercise increased the vertebral mass in group C compared to both groups A and B (rho< 0.01) and the stiffness compared to group B. We concluded the physical activity has an important role to prevent the osteopenia in lumbar vertebrae.

Efeitos do ultra-som terapêutico nas propriedades mecânicas do músculo esquelético após contusão / Effects of therapeutic ultrasound on the mechanical properties of skeletal muscles after contusion

CONTEXTUALIZAÇÃO: O ultra-som terapêutico (UST) é um recurso comumente aplicado na aceleração do reparo tecidual de lesões musculares. A absorção das ondas ultra-sônicas é determinada pela freqüência e pela intensidade, sendo que, em uma mesma intensidade, a profundidade atingida por 1MHz é maior quando comparada a 3MHz. OBJETIVO: Analisar o comportamento das propriedades mecânicas de músculos submetidos à lesão aguda por impacto e tratados com UST, utilizando as freqüências de 1 e 3MHz. MATERIAIS E MÉTODOS: Foram utilizadas 40 ratas Wistar (200,1±17,8g), divididas em quatro grupos: (1) controle; (2) lesão muscular sem tratamento; (3) lesão muscular tratada com UST de freqüência 1MHz (0,5W/cm²) e (4) lesão muscular tratada com UST de freqüência 3MHz (0,5W/cm²). A lesão foi provocada no músculo gastrocnêmio por mecanismo de impacto. O tratamento foi de cinco minutos diários durante seis dias consecutivos. Os músculos foram submetidos a ensaios mecânicos de tração em uma máquina universal de ensaios. RESULTADOS: As médias e desvios-padrão das propriedades mecânicas dos grupos lesionados e tratados com UST foram significativamente maiores quando comparadas ao grupo lesionado sem tratamento (p<0,05). Em destaque, a propriedade de rigidez que, com a aplicação do UST, teve acréscimo de aproximadamente 38 por cento. CONCLUSÕES: A intervenção, por meio do UST, promoveu aumento das propriedades mecânicas nos músculos lesionados aproximando-as do grupo controle. Entretanto, não foi observada diferença significativa entre as propriedades mecânicas dos grupos tratados com ultra-som de freqüências 1MHz e 3MHz.

BACKGROUND: Therapeutic ultrasound is a resource commonly applied to speed up tissue repair in muscle injuries. The absorption of the ultrasound waves is determined by their frequency and intensity. For a given intensity, the depth reached by 1MHz is greater than the depth reached by 3MHz. OBJECTIVE: To analyze the mechanical properties of muscles subjected to acute impact injury treated with therapeutic ultrasound at the frequencies of 1 and 3MHz. METHODS: Forty female Wistar rats (200.1±17.8g) were used, divided into four groups: (1) control; (2) muscle injury without treatment; (3) muscle injury treated with therapeutic ultrasound at the frequency of 1MHz (0.5W/cm²); and (4) muscle injury treated with therapeutic ultrasound at the frequency of 3MHz (0.5W/cm²). The injury was produced in the gastrocnemius muscle by means of an impact mechanism. The treatment consisted of a single five-minute session per day, for six consecutive days. The muscles were subjected to mechanical traction tests in a universal test machine. RESULTS: Means and standard deviations for the mechanical properties of the injured groups that received therapeutic ultrasound were significantly greater than those of the injured group without treatment (p<0.05). The property of stiffness should be highlighted: the application of therapeutic ultrasound increased muscle stiffness by approximately 38 percent. CONCLUSIONS: Therapeutic ultrasound increased the mechanical properties of the injured muscles, and brought them to a level close to the control group. However, no significant difference in mechanical properties was observed between the groups treated with ultrasound at the frequencies of 1MHz and 3MHz.

Morphological comparison of different protocols of skeletal muscle remobilization in rats after hindlimb suspension.

The aim of this study was to evaluate and compare the efficacy of different remobilization protocols in different skeletal muscles considering the changes induced by hindlimb suspension of the tail. Thirty-six female Wistar rats were divided into six groups: control I, control II, suspended, suspended free, suspended trained on a declined treadmill and suspended trained on a flat treadmill. Fragments of soleus and tibialis anterior (TA) muscle were frozen and processed by different histochemical methods. The suspended soleus showed a significant increase in the proportional number of intermediate/hybrid fibers and a decrease in the number of type I fibers. Some of these changes proved to be reversible after remobilization. The three remobilization programs led to the recovery of both the proportional number of fibers and their size. The TA muscle presented a significant increase in the number and size of type I fibers and a cell size reduction of type IIB fibers, which were recovered after training on a declined treadmill and free movement. Especially regarding the soleus, the present findings indicate that, among the protocols, training on a declined treadmill was found to induce changes of a more regenerative nature, seemingly indicating a better tissue restructuring after the suspension procedure.

Influência da imobilização gessada nas propriedades biomecânicas do músculo gastrocnêmio / Influence of immobilization on the biomechanical properties of the gastrocnemius muscle

The study of the effects of the immobilization on the muscular tissue is a very important issue and the measurement of the biomechanics properties provides relevant knowledgement about adaptations occurred from functional demands...

Análise biomecânica do músculo gastrocnêmio de ratas submetidas à natação e ao sedentarismo / Biomechanical analysis of gastrocnemius muscle of rats submitted to swimming and sedentary lifestyle

The purpose of this study was to investigate the influence of physical training and sedentarism on the mechanical properties of striated muscle...

Fuhrmann syndrome: two Brazilian cases.

We describe two unrelated boys with bilateral fibula aplasia, poly- and oligodactyly, and bowed tibiae in two non-consanguineous Brazilian families. These cases are similar to those reported by Fuhrman et al. [(1980). Skeletal Dysplasias. New York: Alan R. Liss Inc. pp. 519-524].

Osteoid osteomas with chromosome alterations involving 22q.

Cytogenetic analysis was performed in two osteoid osteomas. In both, the modal chromosome number was 46. One of the cases presented a del(22)(q13.1) as the sole clonal chromosome alteration. The other had clonal monosomies of chromosomes 3, 6, 9, 17, 19, and 21, as well as a +del(22)(q13.1) was detected as a non-clonal chromosome alteration. There is only one osteoid osteoma reported so far showing clonal karyotypic alterations. The cytogenetic behavior of osteoid osteomas described here was different from that of the osteoid osteoma of the literature. Numerical alterations of chromosomes 3, 6, 9, 17, 19, 21 and 22 have been described in several neoplasias including bone tumors. The breakpoint of chromosome 22 involves a region where important genes for the regulation of the cell cycle have been mapped.

Açäo do ultra-son terapêutico sobre a vascularizaçäo pós-lesäo muscular experimental em coelhos / Action of therapeutic ultrasound on the experimental muscular post-injury vascularization in rabbits

Foi analisado o efeito da aplicaçäo do ultra-som terapêutico na vascularizaçäo do músculo após ser provocada uma lesäo experimental. Foram utilizados 10 coelhas da raça Nova Zelândia, com peso médio de 2,5 kg. Os animais foram submetidos à lesäo por esmagamento do músculo reto femoral em ambas as coxas de acordo com o medelo cirúrgico de Allbrook (1962), e após 24 horas, um dos lados foi tratado com ultra-som terapêutico e, outro, serviu como controle. A frequência utilizada foi de 1 MHz e intensidade de 0, 5 W/cm2 por minutos, durante 10m dias consecutivos. Após 48 horas do término do período de tratamento, os animais foram sacrificados. Realizou-se a lavagem do sistema vascular com soluçäo fisiológicae depois fez-se a injeçäo de uma soluçäo de sulfato de bário e tinta da China por meio de um cateter introduzido na aorta abdominal. Os musculos do fêmur foram ressecados e submetidos ao processo de diafanizaçäo, de acordo com a técnica de Spalteholz. Depois que as peças foram fatiadas e tornaram-se transparentes, foram examinadas por microscópio cirúrgico. Os resultados näo mostraram diferenças no padräo da vascularizaçäo (artérias e arteríolas) entre os lados tratados e näo-tratados, sugerindo que o ultra-som terapêutico näo provocou mudanças no padräo vascular após aplicaçäo precoce em lesäo muscular.

Aplicaçäo de ultra-som terapêutico em lesäo muscular experimental aguda / Application of therapeutic ultrasound in acute experimental muscular injury

Foi analisando o efeito da aplicaçäo do ultra-som terapêutico em lesäo muscular aguda. Foi realizada uma lesäo por esmagamento no músculo reto da coxa direita e esquerda em 26 coelhos (52 músculos) da raça Nova Zelândia, com peso médio de 2,2 kg. Após 3dias da lesäo, os animais foram tratados em um lado com ultra-som terapêutico com tipo de onda pulsada, razäo 1:5, frequência de 1 MHz e intensidade de 0,5 W/cm2 por 5 minutos, durante 10 dias consecutivos. O músculo contralateral serviu como controle e sofreu apenas esmagamento. Após 3 dias do término da aplicaçäo, os animais foram sacrificados e os músculos submetidos a ensaios de traçäo na máquina universal de ensaio, com célula de carga de 2000 kgf e velocidade de 4,5 mm/minuto. Foram analisados os resultados dos ensaios de 36 músculos (18 animais), mostrando que os músculos tratados pelo ultra-som apresentaram diferença significativa na deformaçäo máxima, carga e deformaçäo no limite de proporcionalidade, e na energia na fase de deformaçäo elástica. Estes resultados sugerem que a aplicaçäo do ultra-som terapêutico possa melhorar a qualidade da reparaçäo da lesäo muscular aguda.

Inherited risk factors for thrombophilia among children with Legg-Calvé-Perthes disease.

An inherited tendency to hypercoagulability has been suggested as a cause of vascular thrombosis resulting in Legg-Calvé-Perthes disease (LCPD). Here we carried out an investigation of the most common inherited risk factors for hypercoagulability including the mutation in the factor V gene (factor V Leiden), the transition 20.210G-->A in the prothrombin gene, and also the homozygosity for the 677C-->T transition in the methylenetetrahydrofolate reductase gene (MTHFR). The investigation was carried out among 61 Brazilian children with LCPD, who were compared with 296 individuals from the general population. The prevalence of the factor V Leiden mutation was higher in LCPD patients than in the controls (4.9 vs. 0.7%; p = 0.03). However, no patient had the prothrombin gene variant, and no difference was found between patients and controls when homozygosity for MTHFR-T (3.2 vs. 2.6%: p = 0.64) was determined. These data suggest that in our population, the heterozygosity for factor V Leiden was the only inherited risk factor associated with the development of LCPD.

Ensaios de tração nos ligamentos coracoacromiais e coracoclaviculares de cadáveres humanos / Traction tests in the coracoacromial and coracoclavicular ligaments in human cadavers

Foram utilizados 52 ligamentos (26 coracoacromiais e 26 coracoclaviculares) obtidos de 26 cadáveres humanos do sexo masculino do Serviço de Verificação de àbitos da Faculdade de Medicina da Universidade Federal de Pernambuco. Os ligamentos foram retirados aleatoriamente, durante as aut¢psias, de um dos ombros, direito ou esquerdo, por uma via de acesso ântero-superior. Foram realizados testes de tração nesses ligamentos em uma máquina universal de ensaios com o objetivo de comparar suas propriedades mecânicas, bem como para verificar os locais de ruptura. Ap¢s a análise dos resultados, concluem os autores que, do ponto de vista do comportamento mecânico, os ligamentos coracoacromiais revelaram-se menos resistentes à carga máxima aplicada em relação aos coracoclaviculares. Porém, quando foram consideradas as energias absorvidas na fase elástica e os limites de proporcionalidade, os ligamentos coracoacromiais apresentaram valores médios superiores em relação aos coracoclaviculares. Em todos os ligamentos ensaiados (CA e CC) os locais de ruptura foram nas origens ou nas inserçães ¢sseas e não no corpo ligamentar. Tendo em vista as propriedades mecânicas acima analisadas, os autores sugerem que o ligamento coracoacromial é um bom substituto nos casos de ruptura dos ligamentos coracoclaviculares.