Clinical management of carpal tunnel syndrome: a 12-year review of outcomes

Carpal tunnel syndrome (CTS) is a disorder frequently encountered by occupational health care specialists. The health care management of this disorder has involved a diverse set of clinical procedures. The present article is a review of the literature related to CTS with an emphasis on occupational-related CTS. MEDLINE, Cumulative Index to Nursing and Allied Health Literature, PsycLIT, and NIOSHTIC databases from 1985-1997 were searched for treatment outcome studies related to CTS. Treatments of interest included surgery, physical therapy, drug therapy, chiropractic treatment, biobehavioral interventions, and occupational rehabilitation. A systematic review of the effects of these interventions on symptoms, medical status, function, return to work, psychological well-being, and patient satisfaction was completed. Compared to other treatments, the majority of studies assessed the effects of surgical interventions. Endoscopic release was associated with higher levels of physical functioning and fewer days to return to work when compared to open release. Limited evidence indicated: 1) steroid injections and oral use of B6 were associated with pain reduction; 2) in comparison to splinting, range of motion exercises appeared to be associated with less pain and fewer days to return to work; 3) cognitive behavior therapy yielded reductions in pain, anxiety, and depression; and, 4) multidisciplinary occupational rehabilitation was associated with a higher percentage of chronic cases returning to work than usual care. Workers' compensation status was associated with increased time to return to work following surgery. Conclusions are preliminary due to the small number of well-controlled studies, variability in duration of symptoms and disability, and the broad range of reported outcome measures. While there are several opinions regarding effective treatment, there is very little scientific support for the range of options currently used in practice. Despite the emerging evidence of the multivariate nature of CTS, the majority of outcome studies have focused on single interventions directed at individual etiological factors or symptoms and functional limitations secondary to CTS.     

Concerns of the dry-cleaning industry: a qualitative investigation of labor and management

BACKGROUND: Occupational scientists agree there are hazards associated with dry-cleaning, but do dry-cleaning owners and workers concur? Knowledge of owners' and workers' perceptions can help guide intervention efforts to reduce worker exposure. To better understand these issues, a qualitative study was conducted using focus group methodology and constant comparative analysis. METHODS: Two owner and four worker focus groups were held. RESULTS: Findings suggest that overall, health and safety issues were not of great concern. Owners were primarily concerned with the economic impact of regulations. Workers did express some anxiety about solvent exposure and burns, but most felt that these hazards were "just part of the job." Also, other than the installation of air-conditioning in the shops and the provision of health benefits, workers could not think of ways health and safety on the job could be improved. CONCLUSIONS: These findings will be used to develop comprehensive safety and health interventions (e.g., engineering plus education and training) in dry-cleaning shops.     

Coexpression of leptin receptor and preproneuropeptide Y mRNA in arcuate nucleus of mouse hypothalamus

Leptin, the protein product of the adipose tissue-specific ob (obese) gene (1), reduces the body weight, adiposity and food intake of obese ob/ob mice on peripheral or central injection (2, 3, 4). [125I]leptin binding has been detected in mouse choroid plexus (5), from which a leptin receptor gene was expression cloned (5). The gene has at least 6 splice variants (6, 7). Leptin receptor mRNA was localized in the hypothalamus by in situ hybridization being particularly abundantly expressed in the arcuate nucleus (8). There is evidence linking the physiological effects of injected leptin with hypothalamic neuropeptide Y (9, 10) (NPY), which has potent central effects on food intake and energy balance (11), and is also expressed in the arcuate nucleus. Here we report dual in situ hybridization studies for leptin receptor and NPY gene expression in the mouse arcuate nucleus, where the majority of cells examined expressed both genes. This provides the first direct evidence that leptin acts on cells that express NPY mRNA.     

Uterine activity patterns in uterine rupture: a case-control study

The effects of methylprednisolone therapy on the susceptibility of dystrophin-deficient myofibers to contraction-induced injury were evaluated in the mdx mouse diaphragm model of Duchenne dystrophy. Mdx myofibers were abnormally vulnerable to injury induced by high-stress eccentric contractions. However, methylprednisolone therapy did not significantly alter the degree of contraction-induced injury. These data suggest that beneficial effects of corticosteroid therapy in Duchenne dystrophy are unlikely to be related to a change in the threshold for contraction-induced myofiber damage.     

A randomized phase-II study of BB-10010 (macrophage inflammatory protein- 1alpha) in patients with advanced breast cancer receiving 5-fluorouracil, adriamycin, and cyclophosphamide chemotherapy

BB-10010 is a variant of the human form of macrophage inflammatory protein-1alpha (MIP-1alpha), which has been shown in mice to block the entry of hematopoietic stem cells into S-phase and to increase their self-renewal capacity during recovery from cytotoxic damage. Its use may constitute a novel approach for protecting the quality of the stem cell population and its capacity to regenerate after periods of cytotoxic treatment. Thirty patients with locally advanced or metastatic breast cancer were entered into the first randomized, parallel group controlled phase II study. This was designed to evaluate the potential myeloprotective effects of a 7-day regimen of BB-10010 administered to patients receiving six cycles of 5-fluorouracil (5-FU), adriamycin, and cyclophosphamide (FAC) chemotherapy. Patients were randomized, 10 receiving 100 microgram/kg BB-10010, 11 receiving 30 microgram/kg BB-10010, and nine control patients receiving no BB-10010. BB-10010 was well-tolerated in all patients with no severe adverse events related to the drug. Episodes of febrile neutropenia complicated only 4% of the treatment cycles and there was no difference in incidence between the treated and nontreated groups. Studies to assess the generation of progenitor cells in long-term bone marrow cultures were performed immediately preceding chemotherapy and at the end of six dosing cycles in 18 patients. Circulating neutrophils, platelets, CD 34(+) cells, and granulocyte/macrophage colony-forming cell (GM-CFC) levels were determined at serial time points in cycles 1, 3, and 6. The results showed similar hemoglobin and platelet kinetics in all three groups. On completion of the six treatment cycles, the average pretreatment neutrophil levels were reduced from 5.3 to 1.7 x 10(9)/L in the control patients and from 4.3 to 1.9 and 4.5 to 2.5 x 10(9)/L in the 30/100 microgram/kg BB-10010 groups, respectively. Relative to their pretreatment values, 50% of the patients receiving BB-10010 completed the treatment with neutrophil values significantly higher than any of the controls (P = .02). Mobilization of GM-CFC was enhanced by BB-10010 with an additional fivefold increase over that generated by chemotherapy alone, giving a maximal 25-fold increase over pretreatment values. Bone marrow progenitor assays before and after this standard regimen of chemotherapy indicated little long-term cumulative impairment to recovery from chemotherapy. Despite the limited cumulative damage to the bone marrow, which may have minimized the protective value of BB-10010 during this regimen of chemotherapy, better recovery of neutrophils in the later treatment cycles with BB-10010 was indicated in a number of patients.     

Changes in fetal plasma corticotropin-releasing hormone during androstenedione-induced labor in the rhesus monkey: lack of an effect on the fetal hypothalamo-pituitary-adrenal axis

Androstenedione infusion to pregnant monkeys leads to premature labor and live delivery. Androstenedione-induced labor also increased placental CRH messenger RNA and peptide to concentrations observed at term in pregnant monkeys. Placental CRH may modulate fetal pituitary-adrenal function during pregnancy in primates. This study tested the hypothesis that androstenedione-induced premature delivery in pregnant monkeys results from androstenedione-induced increases in placental CRH, which stimulate premature activation of the fetal pituitary-adrenal axis. The hypothesis was tested by comparing fetal umbilical vein (FUV) plasma CRH, ACTH, dehydroepiandrosterone sulfate, and cortisol concentrations at cesarean section in fetuses from mothers undergoing spontaneous, term labor (group I), with those in fetuses from mothers undergoing androstenedione-induced, premature labor (group II) and with those from mothers not in labor (group III). In addition, gestation-related changes in maternal plasma CRH concentrations were investigated, and CRH immunoactivity was characterized by Sephadex G50 chromatography in pooled maternal plasma extracts. FUV CRH concentrations were similarly elevated in group I and group II fetuses, compared with group III fetuses. Despite similar FUV blood gases in all fetuses, FUV ACTH and dehydroepiandrosterone sulfate concentrations were higher in group I fetuses than in group II or group III fetuses. The majority of CRH immunoactivity coeluted with synthetic human CRH. Maternal plasma CRH concentrations showed a modest increase with gestation in the rhesus monkey. These data: 1) demonstrate that androstenedione treatment of pregnant monkeys at 0.8 of gestation elevates fetal plasma CRH to similar concentrations measured at term; 2) do not support the hypothesis that androstenedione-induced delivery in the monkey results from premature activation of the fetal pituitary-adrenal axis by placental CRH; but 3) do support a role for activation of the fetal hypothalamo-pituitary-adrenal axis in association with spontaneous term labor in the monkey; and 4) demonstrate important interprimate species differences in maternal CRH physiology.