Nerve entrapment complicating neurogenic thoracic outlet syndrome surgery: A 10-year retrospective study.

Neurogenic thoracic outlet syndrome results from compression of the brachial plexus. The symptoms are mainly pain, upper-limb weakness and paresthesia. Management always starts with a rehabilitation program, but failure of rehabilitation may necessitate surgery. In practice, we observed that several patients developed secondary distal nerve entrapment in the months following surgery, with no preoperative compression. We aimed to assess the occurrence of distal nerve entrapment after surgery for neurogenic thoracic outlet syndrome in a retrospective cohort study. Seventy-four patients were included; 82% females; mean age, 39.4 ± 9.4 years. There were 36.5% with high intensity and 63.5% with low to moderate intensity work. Eighteen (24.3%) developed secondary upper-limb entrapment at 10.6 ± 5.8 months after surgery. Sixteen had a single entrapment and 2 had two different entrapments. In 10 cases (50%) the ulnar nerve was involved at the elbow, in 7 (35.0%) the radial nerve at the radial tunnel, and in 3 (15.0%) the median nerve. No differences were found between patients with and without secondary nerve entrapment in gender (p = 0.51), mean age (p = 0.44), symptom duration (p = 0.92) or work intensity (p = 0.26). Further studies are needed to confirm these results and to shed light on the underlying mechanisms.

Joint capsule innervation does not explain the difference in symptoms between scaphotrapezial and trapeziometacarpal osteoarthritis.

OBJECTIVES: Peritrapezial osteoarthritis (OA) includes scaphotrapezial and trapeziometacarpal OA. In clinical practice, scaphotrapezial OA seems better tolerated than trapeziometacarpal OA, with fewer complaints and better tolerance. The difference in pain could be linked to a difference in joint capsule innervation, perhaps with fewer nerve fibers in the scaphotrapezial than the trapeziometacarpal joint. MATERIALS AND METHODS: We performed a histologic evaluation of these two joints to compare their respective innervation in 17 cadaveric specimens with peritrapezial OA. Radiographic scoring confirmed the presence of peritrapezial OA. Mean Kellgren-Lawrence score was 2.2 ± 1.1 in the trapeziometacarpal joint and 1.5 ± 0.7 in the scaphotrapezial joint (p = 0.08). RESULTS: There was no difference between scaphotrapezial and trapeziometacarpal joints in number of neurofilaments: 5.2 ± 3.9 and 4.4 ± 4.5, respectively (p = 0.20). A significant difference was found in S100 staining (myelinated structures), with a higher rate in the scaphotrapezial joint: 11.8 ± 7.5 vs 6.6 ± 5.2 (p = 0.005). CONCLUSION: The present study suggests that lower tolerance of trapeziometacarpal OA is not due to a difference in joint capsule innervation. On the contrary, we found a higher rate of myelinated tissues in the scaphotrapezial joint. These results suggested other pain pathways to explain clinical observations.

Morphological and molecular characterization of Bertiella sp. (Cestoda, Anoplocephalidae) infection in a human and howler monkeys in Argentina.

Bertiella sp. is a typical parasite in non-human primates and only a few cases of bertiellosis have been reported in humans. We present a new case study of bertiellosis in a 42-year-old woman caretaker of howler monkeys in a wild rehabilitation center in Argentina. Bertiella sp. infection was also diagnosed in the monkeys. Proglottids and feces were collected from the caretaker and monkeys; the samples were submitted for parasitological examination by morphological characterization and molecular identification using both nuclear (18S and ITS1-5.8-ITS2 rDNA) and mitochondrial (cox1) markers. Morphological and molecular data were consistent and allowed the classification of the specimen to the genus level. The analyses also showed the presence of cysts of Giardia lamblia and oocysts of Cryptosporidium spp. in howler monkeys, and cysts of Blastocystis sp. in both the caretaker and monkeys. This study recorded the fourth case of bertiellosis in a human host from Argentina and the eighth case in South America. Moreover, this is the first study that compares the morphological and molecular features of Bertiella sp. found in both a human and monkeys from the same geographical region. These results suggest that the cohabitation between humans and monkeys increases the opportunities of infection by Bertiella sp. and other potential zoonotic parasites.

Different surgical approaches to treat chronic tophaceous gout in the hand: our experience.

Chronic tophaceous gout is a disabling erosive arthritis characterized by an elevated serum urate concentration, recurrent attacks of arthritis, and deposits of monosodium urate crystals in synovial fluids. Tophi, ulcerations of the overlying skin, and fissures of the interarticular cartilage may occur in advanced stages, combined with deformities of the joints and decreased active joint flexion and extension. Although the timely use of allopurinol is associated with a decrease in the frequency of deposits of the tophaceous substance, however, surgical management is necessary to restore and improve the cosmesis and joint function, to alleviate symptomatic discomfort, and to reduce the risk of infection when the overlying skin becomes ulcerated. The authors present their experience in the surgical management of the chronic tophaceous gout in the hand.

The RON1/FRY1/SAL1 gene is required for leaf morphogenesis and venation patterning in Arabidopsis.

To identify genes involved in vascular patterning in Arabidopsis (Arabidopsis thaliana), we screened for abnormal venation patterns in a large collection of leaf shape mutants isolated in our laboratory. The rotunda1-1 (ron1-1) mutant, initially isolated because of its rounded leaves, exhibited an open venation pattern, which resulted from an increased number of free-ending veins. We positionally cloned the RON1 gene and found it to be identical to FRY1/SAL1, which encodes an enzyme with inositol polyphosphate 1-phosphatase and 3' (2'),5'-bisphosphate nucleotidase activities and has not, to our knowledge, previously been related to venation patterning. The ron1-1 mutant and mutants affected in auxin homeostasis share perturbations in venation patterning, lateral root formation, root hair length, shoot branching, and apical dominance. These similarities prompted us to monitor the auxin response using a DR5-GUS auxin-responsive reporter transgene, the expression levels of which were increased in roots and reduced in leaves in the ron1-1 background. To gain insight into the function of RON1/FRY1/SAL1 during vascular development, we generated double mutants for genes involved in vein patterning and found that ron1 synergistically interacts with auxin resistant1 and hemivenata-1 but not with cotyledon vascular pattern1 (cvp1) and cvp2. These results suggest a role for inositol metabolism in the regulation of auxin responses. Microarray analysis of gene expression revealed that several hundred genes are misexpressed in ron1-1, which may explain the pleiotropic phenotype of this mutant. Metabolomic profiling of the ron1-1 mutant revealed changes in the levels of 38 metabolites, including myoinositol and indole-3-acetonitrile, a precursor of auxin.