Dorsal dislocation of the ulnar styloid and extensor carpi ulnaris tendon into the distal radioulnar joint: the empty sulcus sign

Two cases of distal radioulnar joint (DRUJ) disruption and diastasis secondary to distal radial fractures were associated with displacement of the ulnar styloid and extensor carpi ulnaris (ECU) into the DRUJ. Both cases had a palpable empty ECU tendon sulcus. In one case surgical exploration revealed that the ulnar styloid, triangular fibrocartilage, and extensor carpi ulnaris tendon had dislocated into the DRUJ as a unit. The end result was good. In the second case lack of recognition and reduction of the ECU tendon and ulnar styloid led to persistent subluxation and diastasis. The end result was poor. Early recognition of the dislocation of the ulnar and ECU into the DRUJ and their significance may avoid poor results.     

Localized cerebral proton MR spectroscopy in HIV infection and AIDS.

PURPOSETo document differences in the cerebral proton MR spectra of patients with early and late stages of human immunodeficiency virus (HIV) infection.METHODWe studied the relative N-acetyl-aspartate (NAA) levels by localized proton spectroscopy of the parietooccipital region of the brain in 43 HIV-seropositive patients, including 26 with an acquired immunodeficiency syndrome (AIDS)-defining diagnosis, and in eight control subjects.RESULTSReduced relative NAA levels were shown in those HIV-1-seropositive patients: 1) with AIDS against HIV-1-seropositive patients without AIDS (P < .04); 2) with HIV-1-associated cognitive/motor complex against neurologically healthy patients (P < .007); 3) with encephalopathic changes on MR against those with normal imaging (P < .001); and 4) on follow-up against their results on initial study (P < .03).CONCLUSIONSBy clinical (Centers for Disease Control classification) and radiologic (MR evidence of white-matter disease) criteria indicating late-stage HIV infection, reduced relative levels of NAA have been demonstrated. Spectroscopic abnormalities can be quantitatively tracked with time. This paper demonstrates the clinical use of detecting NAA as a putative in vivo measure of the neuronal loss that has been demonstrated in postmortem studies of patients with AIDS. This neuronal loss, which is believed to underlie the HIV-1-associated cognitive/motor complex, is thought to be attributable directly or indirectly to the presence of HIV in the brain. Proton spectroscopy may serve as a quantitative noninvasive indicator of this aspect of cerebral involvement in HIV disease.     

Percutaneous bone marrow grafting of fractures and bony defects. An experimental study in rabbits

Since bone marrow has been shown to contain osteoprogenitor cells, an experiment was devised to test its effects when injected percutaneously into osteotomies and 2-cm bony defects produced in rabbit radii. The parameters tested included callus volume, breaking load, tensile strength, and cross-sectional area of callus at the fracture or bony defect site. At two weeks postgrafting callus volume was significantly higher (p less than 0.01) in the grafted radii than in the contralateral saline controls. By four weeks all four parameters were significantly greater in the bone marrow grafted radii than in the contralateral saline controls. Serial radiographs and histology confirm this advanced fracture healing in the grafted bones. The earlier and more abundant callus, at the bone marrow grafted sites, was felt to provide earlier and greater stability, resulting in decreased early healing time when contrasted with the saline controls. Similarly, the bony defects that were grafted with bone marrow united by a bony bridge, whereas the saline controls did not. Percutaneous bone marrow grafting is a simple semi-invasive technique that may have potential clinical applications.     

Systemic necrotizing vasculitis associated with childhood sarcoidosis

Childhood sarcoidosis is a rare disorder with protean manifestations. The case of a child with prolonged fever, hepatosplenomegaly, pancytopenia, and systemic necrotizing vasculitis manifesting as fever, rash and skin infarctions, digital pregangrene, and foot drop is reported. This is the first case of systemic necrotizing vasculitis reported in sarcoidosis. The fulminant course of the disease required treatment with intravenous pulsed cyclophosphamide and high doses of corticosteroids. The spectrum of vasculitis in childhood and adult sarcoidosis is reviewed.     

A model for susceptibility artefacts from respiration in functional echo-planar magnetic resonance imaging

Respiration causes variations in the signals acquired during magnetic resonance imaging (MRI) and therefore is a significant source of noise in functional brain imaging. A primary component of respiratory noise may arise from variations of bulk susceptibility or air volume in the chest. Here we investigate the nature of the image artefacts that can be caused by such changes. We develop a simple model which attempts to mimic the effects of variations in susceptibility and volume during respiration. Theoretical calculations, computer simulations and imaging experiments with this model show that small variations in susceptibility within the thorax from alterations in the paramagnetism of cavity gas may lead to a shift of the image on the order of 0.1 pixels as well as a shading of the intensity by +/-1%. These effects are observed to be predominant in the phase-encoding direction. They may lead to the production of spurious activations in functional MRI and are likely to be of more importance at higher field strengths.     

Improvement in gait parameters after lengthening for the treatment of limb-length discrepancy

BACKGROUND: Patients who have limb-length discrepancy demonstrate an altered gait pattern or a limp. The purpose of this prospective study was to compare the objective gait parameters for the shorter lower limb with those for the longer lower limb before and after lengthening and to compare these data with those for a group of twenty subjects who had no limb-length discrepancy. METHODS: Eighteen patients had equalization of limb length to within one centimeter. We analyzed the stance time, the second peak of the vertical ground-reaction-force vector, and the rate of loading with use of two force-plates arranged in a series. RESULTS: The difference in the mean stance times between the shorter and longer limbs before lengthening was 12 percent, whereas that after lengthening was 2.4 percent; the difference between the values before and after lengthening was significant (p<0.001). The difference in the stance times between the limbs of the patients who did not have limb-length discrepancy was 2 percent. Preoperatively, the mean second peak was 104 percent of body weight for the shorter limb compared with 116 percent for the longer limb; this difference was significant (p<0.001). After lengthening, the mean second peak for the shorter limb increased to 113 percent of body weight. The difference in the means for the second peak before and after lengthening was significant (p<0.001). With the numbers available, no significant difference was detected in the means for the second peak between the shorter and longer limbs after lengthening (p = 0.12). CONCLUSIONS: This study shows that lengthening of the shorter limb of patients who have limb-length discrepancy can normalize symmetry of quantifiable stance parameters and eliminate a limp.     

The adaptation of perimuscular connective tissue during distraction osteogenesis

It is not known whether the decreased range of motion observed during distraction osteogenesis results from the lack of adaptation of muscle or from fibrosis in the perimysium. The adaptation of the perimysium in the tibialis anterior muscle in skeletally immature rabbits using two distraction regimens (0.7 and 1.4 mm/day with 15% lengthening) was characterized. The resulting data indicate that during distraction osteogenesis, the muscle adapts by reorganization of its connective tissue. At a lengthening rate of 1.4 mm/day, there is perimysial fibrosis without major cellular pathologic abnormalities in the muscle fibers. The increase in perimysial thickness is characterized by an increase of collagen Type I. In addition, collagen Type I is deposited around the endomysium. The increase in total collagen and its cross-linking are dependent on the lengthening rate. The faster lengthening rate also leads to a significant decreased passive plantar flexion. Supplemental growth of the tibia was not observed, and a lack of adaptation in the muscle (based on resting length) was not seen. Together, the data suggest that decreased range of motion during distraction osteogenesis may be a function of the adaptation of the perimysium rather than of the muscle fibers.     

Behavioral Regulation as a Predictor of Response to Children's Friendship Training in Children with Fetal Alcohol Spectrum Disorders

Children with fetal alcohol spectrum disorders (FASDs) evidence an array of structural brain abnormalities and neurocognitive deficits. Furthermore, previous research suggests that deficits in executive functioning (EF) may be associated with significant difficulties in the formation of positive peer relationships in this population. The purpose of the current study was to examine the role of EF as a predictor of treatment response to a controlled social skills intervention for children with FASDs. A total of 100 children between the ages of 6 and 12 received Children's Friendship Training (CFT). Prior to treatment, parents completed the Behavior Rating Inventory of Executive Functioning (BRIEF). Treatment outcome was measured using parent report on the Social Skills Rating System (SSRS). The results demonstrated that behavioral regulation as measured on the BRIEF predicted the effectiveness of CFT for children with FASDs, regardless of general intellectual functioning. Specifically, the ability to control impulses, solve problems flexibly, and monitor emotional responses significantly predicted improvement in social skills and reduction in problem behaviors following CFT.     

The therapist's voice

Hope has long been recognized as a vital element of the therapeutic process. We know that a fair percentage of clients do not recover, yet, to do our work effectively, we must balance acceptance of a person "as is" with the hope for change. Learning to bear the unfinished chapters is perhaps one of our most difficult lessons, as is indicated in the following vignette.     

Mapping and molecular characterization of novel monoclonal antibodies to conformational epitopes on NH2 and COOH termini of mammalian tryptophanyl-tRNA synthetase reveal link of the epitopes to aggregation and Alzheimer's disease

Tryptophanyl-tRNA synthetase (TrpRS) is an interferon-induced phosphoprotein with autoantigenic and cytokine activities detected in addition to its canonical function in tRNA aminoacylation. The availability of monoclonal antibodies (mAbs) specific for TrpRS is important for development of tools for TrpRS monitoring. A molecular characterization of two mAbs raised in mice, using purified, enzymatically active bovine TrpRS as the inoculating antigen, is presented in this report. These IgG1 antibodies are specific for bovine, human and rabbit but not E. coli TrpRS. Immunoreactivity and specificity of mAbs were verified with purified recombinant hTrpRS expressed in E. coli and TrpRS-derived synthetic peptides. One of the mAbs, 9D7 is able to disaggregate fibrils formed by Ser32-Tyr50 TrpRS-peptide. Epitope mapping revealed that disaggregation ability correlates with binding of 9D7 to this peptide in ELISA and immunocytochemistry. This epitope covers a significant part of N-terminal extension that suggested to be proteolytically deleted in vivo from the full-length TrpRS whereas remaining COOH-fragment possesses a cytokine activity. For epitope mapping of mAb 6C10, the affinity selected phage-displayed peptides were used as a database for prediction of conformational discontinuous epitopes within hTrpRS crystal structure. Using computer algorithm, this epitope is attributed to COOH-terminal residues Asp409-Met425. In immunoblotting, the 6C10 mAb reacts preferably with (i) oligomer than monomer, and (ii) bound than free TrpRS forms. The hTrpRS expression was shown to correlate with growth rates of neuroblastoma and pancreatic cancer cells. Immunohistochemically both mAbs revealed extracellular plaque-like aggregates in hippocampus of Alzheimer's disease brain.