CONTEXT Risedronate, a potent bisphosphonate, has been shown to be effective
in the treatment of Paget disease of bone and other metabolic bone diseases
but, to our knowledge, it has not been ...evaluated in the treatment of established
postmenopausal osteoporosis. OBJECTIVE To test the efficacy and safety of daily treatment with risedronate
to reduce the risk of vertebral and other fractures in postmenopausal women
with established osteoporosis. DESIGN, SETTING, AND PARTICIPANTS Randomized, double-blind, placebo-controlled trial of 2458 ambulatory
postmenopausal women younger than 85 years with at least 1 vertebral fracture
at baseline who were enrolled at 1 of 110 centers in North America conducted
between December 1993 and January 1998. INTERVENTIONS Subjects were randomly assigned to receive oral treatment for 3 years
with risedronate (2.5 or 5 mg/d) or placebo. All subjects received calcium,
1000 mg/d. Vitamin D (cholecalciferol, up to 500 IU/d) was provided if baseline
levels of 25-hydroxyvitamin D were low. MAIN OUTCOME MEASURES Incidence of new vertebral fractures as detected by quantitative and
semiquantitative assessments of radiographs; incidence of radiographically
confirmed nonvertebral fractures and change from baseline in bone mineral
density as determined by dual x-ray absorptiometry. RESULTS The 2.5 mg/d of risedronate arm was discontinued after 1 year; in the
placebo and 5 mg/d of risedronate arms, 450 and 489 subjects, respectively,
completed all 3 years of the trial. Treatment with 5 mg/d of risedronate,
compared with placebo, decreased the cumulative incidence of new vertebral
fractures by 41% (95% confidence interval CI, 18%-58%) over 3 years (11.3%
vs 16.3%;P=.003). A fracture reduction of 65% (95%
CI, 38%-81%) was observed after the first year (2.4% vs 6.4%; P<.001). The cumulative incidence of nonvertebral fractures over
3 years was reduced by 39% (95% CI, 6%-61%) (5.2% vs 8.4%; P=.02). Bone mineral density increased significantly compared with
placebo at the lumbar spine (5.4% vs 1.1%), femoral neck (1.6% vs −1.2%),
femoral trochanter (3.3% vs −0.7%), and midshaft of the radius (0.2%
vs −1.4%). Bone formed during risedronate treatment was histologically
normal. The overall safety profile of risedronate, including gastrointestinal
safety, was similar to that of placebo. CONCLUSIONS These data suggest that risedronate therapy is effective and well tolerated
in the treatment of women with established postmenopausal osteoporosis.
Proximal row carpectomy (PRC) and scaphoid excision with four-corner fusion (4CF) are common motion-preserving, salvage procedures for the treatment of wrists with scaphoid nonunion (SNAC) or ...scapholunate advanced collapse (SLAC). A systematic review was undertaken to clarify controversies regarding which of these procedures has the better outcome. We collated 52 articles that examine outcomes for SNAC or SLAC patients undergoing PRC or 4CF. Although the lack of unbiased trials must be acknowledged, this systematic review confirms that both procedures give improvements in pain and subjective outcome measures for patients with symptomatic and appropriately staged SLAC or SNAC wrists. PRC may provide better postoperative range of movement and lacks the potential complications specific to 4CF (nonunion, hardware issues and dorsal impingement). However, the risk of subsequent osteoarthritis is significantly higher in PRC patients despite the majority being asymptomatic at the time of review. Grip strength, pain relief and subjective outcomes are similar in both treatment groups.
Using 7 yr of MACHO survey data, we present a new determination of the optical depth to microlensing toward the Galactic bulge. We select the sample of 62 microlensing events (60 unique) on clump ...giant sources and perform a detailed efficiency analysis. We use only the clump giant sources because these are bright bulge stars and are not as strongly affected by blending as other events. Using a subsample of 42 clump events concentrated in an area of 4.5 deg super(2) with 739,000 clump giant stars, we find t = 2.17 super(+) sub(-) super(0) sub(0) super(.) sub(.) super(4) sub(3) super(7) sub(8) x 10 super(-6) at (l,b) = (1.50, - 2.68), somewhat smaller than found in most previous MACHO studies but in excellent agreement with recent theoretical predictions. We also present the optical depth in each of the 19 fields in which we detected events and find limits on optical depth for fields with no events. The errors in optical depth in individual fields are dominated by Poisson noise. We measure optical depth gradients of (1.06 c 0.71) x 10 super(-6) deg super(-1) and (0.29 c 0.43) x 10 super(-6) deg super(-1) in the Galactic latitude b and longitude l directions, respectively. Finally, we discuss the possibility of anomalous duration distribution of events in the field 104 centered on (l,b) = (3.11, - 3.01), as well as investigate spatial clustering of events in all fields.
Two patients are reported who had tendon rupture and plate breakage following internal fixation with the newly designed AO/ASIF titanium distal radius plate system (π plate). The incidence of ...complications with this system warrants further evaluation.
A study conducted a microlensing experiment to determine whether the dark matter halo in the Milky Way is made up of massive compact halo objects (MACHOs). Evidence from one microlensing event is ...offered.
The nature of dark matter remains mysterious, with luminous material accounting for at most ∼25 per cent of the baryons in the Universe. We accordingly undertook a survey looking for the microlensing ...of stars in the Large Magellanic Cloud (LMC) to determine the fraction of Galactic dark matter contained in massive compact halo objects (MACHOs). The presence of the dark matter would be revealed by gravitational lensing of the light from an LMC star as the foreground dark matter moves across the line of sight. The duration of the lensing event is the key observable parameter, but gives non-unique solutions when attempting to estimate the mass, distance and transverse velocity of the lens. The survey results to date indicate that between 8 and 50 per cent of the baryonic mass of the Galactic halo is in the form of MACHOs (ref. 3), but removing the degeneracy by identifying a lensing object would tighten the constraints on the mass in MACHOs. Here we report a direct image of a microlens, revealing it to be a nearby low-mass star in the disk of the Milky Way. This is consistent with the expected frequency of nearby stars acting as lenses, and demonstrates a direct determination of a lens mass from a microlensing event. Complete solutions such as this for halo microlensing events will probe directly the nature of the MACHOs.
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