A pilot study of metabolic fitness effects of weight-supported walking in women with obesity.

BACKGROUND: This is an exploratory pilot study of novel technology enabling people with mobility disability to walk with minimal effort, in the "sedentary range". The study's premise is that impairment of the leading physical activity of daily living, walking, is a major contributor to a dysmetabolic state driving many prevalent "civilization diseases" associated with insulin resistance. METHODS: We explore within-subject changes in standard oral glucose tolerance (OGT) tests including metabotropic molecules after 22 twice-weekly, 30-minute bouts of weight-supported light-moderate physical activity in 16 non-diabetic obese, otherwise healthy, reproductive-age, volunteer women walking on an "anti-gravity" lower-body positive pressure (LBPP) treadmill. RESULTS: Subjects had reference base-line fasting plasma glucose and triglycerides (TG) but 2-hr OGT insulin levels of 467 ± 276 pmol • liter-1 (mean± S.D.) indicating nascent insulin resistance, compared to post-study 308 ± 179 (p = 0.002). Fasting TG decreased from 0.80 ± 0.30 mmol • liter-1 to 0.71 ± 0.25 (p = 0.03). Concomitantly plasma total ghrelin decreased from 69.6 ± 41.6 pmol • liter-1 to 56.0 ± 41.3 (p = 0.008). There were no statistically significant changes in body weight or any correlations between weight change and cardiometabolic markers. However, there were robust positive correlations between changes among different classes of peptides including C-reactive protein-Interleukin 6, leptin-adiponectin, ß-endorphin-oxytocin and orexin A (r 2 = 0.48-0.88). CONCLUSION: We conclude that brief, low-dose physical activity, walking on an anti-gravity LBPP treadmill may improve cardiometabolic risk, exhibiting favorable changes in neuro-regulatory peptides without weight loss in people with problems walking.

Ghrelin, Amylin, Gastric Inhibitory Peptide and Cognition in Middle-Aged HIV-Infected and Uninfected Women: The Women's Interagency HIV Study.

OBJECTIVE: To explore the gut-brain axis by examining gut hormone levels and cognitive test scores in women with (HIV+) and without (HIV-) HIV infection. DESIGN/METHODS: Participants included 356 women (248 HIV+, 108 at risk HIV-) in the Brooklyn Women's Interagency HIV Study (WIHS) with measured levels of ghrelin, amylin and gastric inhibitory peptide (GIP), also known as glucose-dependent insulinotropic polypeptide. Cross-sectional analyses using linear regression models estimated the relationship between gut hormones and Trails A, Trails B, Stroop interference time, Stroop word recall, Stroop color naming and reading, and Symbol Digit Modalities Test (SDMT) with consideration for age, HIV infection status, Wide Range Achievement Test score (WRAT), CD4 count, insulin resistance, drug use, and race/ethnicity. RESULTS: Among women at mid-life with chronic (at least 10 years) HIV infection or among those at risk, ghrelin, amylin and GIP were differentially related to cognitive test performance by cognitive domain. Better performance on cognitive tests was generally associated with higher ghrelin, amylin and GIP levels. However, the strength of association varied, as did significance level by HIV status. CONCLUSION: Previous analyses in WIHS participants have suggested that higher BMI, waist, and WHR are associated with better cognitive function among women at mid-life with HIV infection. This study indicates that higher gut hormone levels are also associated with better cognition. Gut hormones may provide additional mechanistic insights regarding the association between obesity and Type 2 diabetes and cognition in middle-aged HIV+ and at risk HIV- women. In addition, measuring these hormones longitudinally would add to the understanding of mechanisms of actions of these hormones and their use as potential clinical tools for early identification and intervention on cognitive decline in this vulnerable population.

An innovative approach to concave-convex allograft junctions: a biomechanical study.

Allograft bone is often used in oncologic and trauma limb salvage procedures. In this study, we hypothesize that a concave-convex allograft junction with plate fixation would improve multiple aspects of the reconstruction process, allowing for a larger contact surface area between the allograft junction and increased uniformity in pressure distribution at the junction. Thirty large femoral artificial polyresin femurs were randomly separated into 2 groups: allograft junctions fixed with flat locking plates and allograft junctions fixed with prebent locking plates. Each group was then randomly subdivided into 3 sets: concave-convex allograft junctions, matched transverse-cut allograft junction, and non-matched transverse-cut allograft junctions. All but 1 reconstructions of concave-convex allograft junctions, compared with non-matched or matched transverse-cut allograft junctions fixed with flat or pre-bent locking plates showed statistically significantly greater mean contact surface area and greater mean percent contact surface area (P<.05). Concave-convex allograft junctions demonstrated increased mean contact surface area, mean percent contact surface area, and a more uniform pressure distribution. We believe our approach to allograft junctions using concave-convex reamers may improve multiple aspects of the reconstruction process, allowing for increased contact surface area between the allograft junction, increased uniformity in pressure distributions at the allograft junction, and decreased length of time taken for intraoperative preparation.

Comparison of phenol and argon beam coagulation as adjuvant therapies in the treatment of stage 2 and 3 benign-aggressive bone tumors.

Argon beam photocoagulation has gained popularity as an adjuvant therapy for the treatment of giant cell tumors of bone and other stage 2 or 3 benign-aggressive bone tumors. Although argon beam photocoagulation has been considered a safe and reasonable adjuvant treatment with acceptable recurrence rates, it has never been directly compared with the commonly described phenol as adjuvant. The purpose of this study was to determine whether argon beam photocoagulation is as effective as phenol in preventing recurrence without affecting functional outcome as an adjuvant to surgical curettage. We retrospectively reviewed 93 consecutive patients with a minimum 10-month follow-up between 1992 and 2007 who were treated with curettage and either phenol or argon beam photocoagulation. Functional outcomes and complications were recorded. Overall, 16 (17.2%) of 93 patients who were initially treated with 1 of the adjuvants had pathologically confirmed recurrences. No additional recurrences were noted after retreatment, leading to an overall recurrence rate of 17.1% with phenol and 14.8% with argon beam photocoagulation (P=.726). While avoiding the toxic effects of phenol, argon beam photocoagulation provides for statistically equivalent recurrence rates, functional outcomes, and complication rates in the treatment of benign-aggressive bone tumors.

An evaluation of brachytherapy and external beam radiation used with wide-margin surgical resection in the treatment of extra-abdominal desmoid tumors.

Surgical resection has had control rates of 53% to 77% in the treatment of extra-abdominal desmoid tumors. Surgical excision combined with external beam radiation therapy (EBRT) has had local control rates of up to 83% in some series. The purpose of this study was to evaluate the effectiveness of resection combined with radiotherapy (brachytherapy, EBRT, or both) in the treatment of extra-abdominal desmoid tumors. We retrospectively reviewed the charts of 24 consecutive patients (27 histologically confirmed extra-abdominal desmoid tumors). Patients were included in the study if they had a lesion that was potentially resectable with a wide margin, allowing for limb salvage, and if they did not have a contraindication to radiotherapy. Limb functioning was assessed with the Musculoskeletal Tumor Society (MSTS) scoring system. Seventeen patients (7 men, 10 women) with 19 tumors met the inclusion criteria. Mean age at diagnosis was 23.4 years. Follow-up (mean, 4.28 years) involved serial clinical examinations and magnetic resonance imaging of tumor sites. After surgery, the tumors were treated with brachytherapy (n = 6), EBRT (n = 10), or both (n = 3). Two of the 17 tumors in patients with negative margins of resection recurred locally (local control rate, 88.2%). Mean MSTS score was 29/30 (96.7%). The role of surgery, radiotherapy, chemotherapy, hormone therapy, and other treatments for extra-abdominal desmoid tumors is not well defined. When wide-margin resection and radiotherapy can be performed with limb preservation surgery, local control and complication rates compare favorably with those of other reported methods of treatment. Given the results and limitations of our study, we cannot make a definitive recommendation as to which modality--brachytherapy or EBRT--should be used in the treatment of extra-abdominal desmoid tumors.

Evaluation of a noninvasive expandable prosthesis in musculoskeletal oncology patients for the upper and lower limb.

The noninvasive expandable prosthesis is used for limb-salvage surgery following tumor resection in skeletally immature patients. The purpose of this retrospective study is to report our experience with the Repiphysis (Wright Medical Technology, Inc; Arlington, Tennessee) noninvasive expandable prosthesis for both the lower extremity and compassionate use in the upper extremity in 12 patients between 2003 and 2008. Twelve prostheses were implanted in 12 patients with an average follow-up of 38 months (range, 12-78 months). Nine patients underwent a total of 38 expansion procedures. Mean total expansion was 4.5 cm (range, 0.8-9.9 cm). No complications of lengthening occurred. Seven nononcologic complications were noted. One infection was reported in 12 patients. The mean MSTS score after rehabilitation was 24.5 (range, 13-30). The Repiphysis noninvasive prosthesis provides acceptable functional outcomes for both upper and lower extremity implantation and appears to have an advantage as compared to conventional expandable prosthetics, which require open procedures that can potentially increase the risk of infection from repeated hardware exposure.

Recurrent knee pain in an athletic adult: multiple schwannomas secondary to schwannomatosis: a case report.

Schwannomatosis has been used to describe patients with multiple nonvestibular schwannomas with no associated features of neurofibromatosis type 2. In our case, a 28-year-old athletic man underwent a right knee excisional biopsy for multifocal, benign schwannomatosis. After being asymptomatic for 4 years postresection, he returned to our musculoskeletal oncology service. Imaging studies revealed local recurrence identical to his initial presentation. Excisional biopsy of discrete masses was performed and histologic examination revealed recurrent benign schwannomatosis. To our knowledge, this is the second reported case of recurrent benign schwannomatosis. We review schwannomatosis, including its etiology, radiographic features, and relationship to neurofibromatosis.

Distal femur defects reconstructed with polymethylmethacrylate and internal fixation devices: a biomechanical study.

Benign aggressive distal femur tumors are treated with curettage, adjuvant phenol or argon, and polymethylmethacrylate (PMMA) packing. For large defects, an internal fixation device is added to reduce the fracture risk. The purpose of this study is to compare the strength of locking plates to other fixation devices for stabilization of these defects. Lateral condyle defects in young, fresh frozen femurs were packed with PMMA and augmented by internal fixation. Three groups of 4 matched pairs of femurs were organized for the following comparisons: (1) stacked Steinmann pins vs crossed screws; (2) stacked pins vs locking plates; and (3) crossed screws vs locking plates. Specimens were subjected to axial load-to-failure testing on an MTS machine. There was no difference in load-to-failure strength (P=.177) using Steinmann pins or crossed screws. Locking plate constructs were stronger (P=.028) than Steinmann pin constructs. Locking plate constructs were also stronger (P<.001) than crossed-screw constructs. Steinmann pin constructs failed with severe intra-articular fractures; crossed screw constructs failed with bulging of the defects, articular impaction, and minimal fracture propagation. Locking plate constructs failed with extra-articular spiral shaft fractures.

A rare case of intraosseous benign notochordal cell tumor of the coccyx.

This article presents a case of a 53-year-old woman who presented with intermittent, dull, poorly localized lower back and buttock pain. The pain worsened in a seated position or after long periods of standing. A T1-weighted magnetic resonance image (MRI) of the sacrum and coccyx revealed a well-demarcated intraosseous lesion with homogeneous low signal intensity, while T2-weighted MRIs demonstrated homogeneous high signal intensity. An excisional biopsy revealed benign notochord cell tumor. The biopsy proved to be effective, as it relieved the patient's coccydynia. Due to the rarity of intraosseous benign notochordal cell tumors, it is essential to document and review this type of tumor. Only 2 benign notochordal cell tumors involving the coccyx have been previously reported, both of which presented with the same clinical symptoms of chronic coccydynia as our patient, likely due to the location of the involved lesion. The other leading diagnosis in our patient was chordoma, a malignant and locally aggressive neoplasm that is important to consider and exclude. Although chordomas have been well characterized in the surgery, pathology, and radiology literature, the benign notochordal cell tumor is a relative newcomer.