Case presentation: Concomitant avulsion fracture of the posterior calcaneal tubercle and rupture of the Achilles tendon. / Presentación de caso: fractura avulsión del tubérculo posterior de calcáneo con rotura de tendón de Aquiles en un tiempo.

The Achilles tendon acts by transmitting the force created by the contraction of the sural triceps to the calcaneus. This allows the elevation during the gait cycle. A sudden contraction in elderly patients may generate avulsion fracture of the posterior tubercle of the calcaneus due to poor bone quality or rupture of the tendon, with one of these two structures yielding in most cases. We report the case of a 72-year-old woman who suffered a low energy right heel trauma while stepping off the bus. She was diagnosed an avulsion fracture of the posterior tubercle of the calcaneus. When performing ORIF procedure of the fracture, an associated rupture of the Achilles tendon is diagnosed. Both pathologies are treated in the same surgical act. We recommend using a second imaging study along with the x-ray in order to anticipate associated injuries and adequate surgical planning in elderly patients.

Refinement of the dopaminergic system of anuran amphibians based on connectivity with habenula, basal ganglia, limbic system, pallium, and spinal cord.

Whereas our understanding of the dopaminergic system in mammals allows for a distinction between ventral tegmental area (VTA) and substantia nigra pars compacta (SNc), no clear evidence for separate structures in anamniotes has been presented to date. To broaden the insight into the organization and regulation of neuromodulatory systems in anuran amphibians, tracing and immunohistochemical investigations were performed in the Oriental fire-bellied toad, Bombina orientalis. Topographically organized catecholaminergic "nigrostriatal," "mesolimbic," "mesocortical," and spinal cord projections arising from the posterior tubercle and mesencephalic tegmentum were identified. We compared these results with published data from lampreys, chondrichthyes, teleosts, amphibians, reptiles, birds, and mammals. Based on the pattern of organization, as well as the differential innervation by the habenular nuclei, domains gradually comparable to the mammalian paranigral VTA, ventral tier of the SNc, interfascicular nucleus of the VTA, and supramamillary/retromamillary area were identified. Additionally, we could demonstrate topographic separate populations of habenula neurons projecting via a direct excitatory or indirect GABAergic pathway onto the catecholaminergic VTA/SNc homologs and serotonergic raphe nuclei. The indirect GABAergic habenula pathway derives from neurons in the superficial mamillary area, which in terms of its connectivity and chemoarchitecture resembles the mammalian rostromedial tegmental nucleus. These results demonstrate a much more elaborate interconnection principle of the anuran dopaminergic system than previously assumed. Based on the data presented it seems that most features of the dopaminergic system of amniotes had already evolved when the amphibian line of evolution diverged from that leading up to mammals, reptiles, and birds.

Organization of the catecholaminergic systems in two basal actinopterygian fishes, Polypterus senegalus and Erpetoichthys calabaricus (Actinopterygii: Cladistia).

Cladistians are a group of basal nonteleost actinopterygian fishes that represent an interesting group for the study of primitive brain features, most likely present in the ancestral Osteichthyes. We have investigated the catecholaminergic (CA) systems in the brain of two representative cladistian species, the bichir Polypterus senegalus and the reedfish Erpetoichthys calabaricus, by means of antibodies against tyrosine hydroxylase (TH; the first enzyme in the synthesis of catecholamines) and dopamine (DA). Double immunohistofluorescence was performed for simultaneous detection of TH with nitric oxide synthase, choline acetyltransferase, calbindin, calretinin, and serotonin, aiming to accurately establish the localization of the CA neurons and to assess possible interactions between these neuroactive substances. All forebrain CA groups of cladistians are dopaminergic, whereas noradrenergic cells are located within the rhombencephalon. Distinct groups of DA immunoreactive (DA-ir) cells were observed in the olfactory bulb, subpallium, and preoptic area of the telencephalon. Hypothalamic groups were detected in the suprachiasmatic nucleus, retrotuberal and retromamillary areas and, in particular, the paraventricular organ showed immunoreactivity to dopamine but not to TH. Diencephalic DA-ir groups were detected in the prethalamus, posterior tubercle, and pretectum. A small DA-ir cell population was observed in the midbrain tegmentum only in Polypterus. CA cell groups were also located in the locus coeruleus, solitary tract nucleus, and area postrema within the rhombencephalon, the spinal cord, and the retina. The comparison of these results with other vertebrates, using a neuromeric analysis, shows highly conserved traits in all vertebrates studied but also evidences particular characteristics of actinopterygian fishes.

"Suspended Posterior Tubercle of Atlas" with Atlantoaxial Dislocation.

INTRODUCTION: Congenital anomaly of the C1 posterior arch is a well-known entity and is often associated with atlantoaxial dislocation. However, a well-formed C1 posterior tubercle with absence of the remaining posterior arch is rare. Such unusual anomalies pose a surgical challenge as trying to delineate the arch early in the course of surgery could be potentially dangerous. We discuss here a similar case of C1 posterior arch defect with atlantoaxial dislocation and its management. CASE REPORT: A 17-year-old female presented with progressive spastic quadriparesis and neck pain. Evaluation revealed atlantoaxial dislocation with the presence of a well-formed posterior C1 tubercle in the absence of the rest of the posterior arch. C1-C2 joints were opened, and lateral masses were fused in reduced position. Intraoperatively, a posterior C1 tubercle was found suspended from the lateral masses by fibrous bands. The surgical nuances have been discussed. CONCLUSION: Presence of posterior tubercle alone with aplasia of the posterior arch results from a persistent posterior ossification center with nonextension of lateral ossification centers. In the presence of the C1 posterior fibrous arch, the joint spaces must be exposed first before attempting to delineate the posterior arch. This will prevent inadvertent injury to the vertebral artery and dura.

Control Study of Cervical Spondylotic Radiculopathy Treated by Loosening Posterior Tubercle of Cervical Transverse Process with CT-guided Insertion of Small Needle Knife and Blind Insertion of Small Needle Knife / 广州中医药大学学报

Objective To investigate the successful rate and the therapeutic effect of loosening posterior tubercle of cervical transverse process with CT-guided insertion or blind insertion of small needle knife for cervical spondylotic radiculopathy. Methods Ninety patients with cervical spondylotic radiculopathy were divided into CT-guided insertion group and blind insertion group in the admission order using the random number table method, 45 cases in each group. CT-guided insertion group adopted the insertion of small needle knife following by the guide of CT, and the blind insertion group adopted the insertion of small needle knife following by cervical bony landmarks and muscles. After insertion, the position of the small needle knife in patients of the two groups was located by CT scan. If the needle knife did not arrive to the foci, it will be inserted again following by the guide of CT till successful insertion and location. The successful rate for the two times of insertion was calculated, and the pain scores were evaluated by visual analogue scale(VAS). Results(1) The successful rate for the first insertion of CT-guided insertion group was 73.3％, and that of the blind insertion group was 47.8％, the difference being significant(P < 0.01). The successful rate for the second insertion of CT-guided insertion group was 92.2％, and that of the blind insertion group was 80.0％, the difference being significant (P<0.01). (2) After treatment for one week, pain VAS scores of the two group were decreased (P < 0.01 compared with those before treatment) , and the decrease in the CT-guided insertion group was more obvious than the blind insertion group (P < 0.05). Conclusion CT-guided insertion makes the small needle knife therapy be more accurate and safer, ensures much better therapeutic effect, and brings less pain in the patients.

Percutaneous Posterior Calcaneal Osteotomy.

Different types of posterior calcaneal osteotomy are used for calcaneal realignment in the management of hindfoot deformity. We describe a percutaneous technique of posterior calcaneal osteotomy that can be either a Dwyer-type closing wedge osteotomy or displacement osteotomy.

Congenital Absence of the Posterior Arch of the Atlas A Strange but Benign Anomaly

Congenital partial aplasia of the atlas with a posterior arch remnant is rare. It may be found as an incidental radiological finding or patients can present with neurological signs and symptoms after head or neck trauma. A 36 year old female presented with a 3 day history of right sided neck pain radiating down the right arm. Radiographs of the cervical spine showed a radiolucent area in the region of the posterior arch of the atlas. Computed tomography subsequently revealed partial absence of the posterio