An ex vivo investigation of the effect of the TATE canine elbow arthroplasty system on kinematics of the elbow.

OBJECTIVE: To devise a kinematic technique to objectively ascertain the location and orientation of the centre of rotation of the canine elbow and to compare this axis following arthroplasty with the first generation TATE™ prosthesis in an ex vivo model. METHODS: Five pairs of cadaveric forelimbs were obtained and proximal limb soft tissues removed. Pin-mounted reflective markers were applied to the humerus and ulna. Limbs were mounted on a frame and six trials of the elbow manually cycled through its sagittal range of motion captured using 4 Qualisys cameras at 120 Hz. Radiography was performed to identify marker position. TATE™ cartridges were implanted and kinematic analysis repeated. Kinematic data were imported into custom software and the three-dimensional joint centre of rotation defined using a closed-form solution for absolute orientation. Paired t tests were performed to determine if the centre of rotation of the elbow differed significantly (P<0·05) pre- and postoperatively and between left and right limbs. RESULTS: There was no significant difference in three-dimensional orientation of the elbow axis between pre and postoperative measurements or between left and right limbs. CLINICAL SIGNIFICANCE: A critical factor in obtaining a successful functional outcome following elbow arthroplasty in humans is accurate reconstruction of the anatomic centre of rotation. The first generation TATE canine elbow arthroplasty cartridge and its instrumentation accurately reconstructed the anatomic centre of rotation in 8 of the 10 elbows assessed in this ex vivo model.

Complications of circular plate fixation for four-corner arthrodesis.

Four corner arthrodesis is an accepted salvage operation for scapholunate advanced collapse and scaphoid non-union advanced collapse. Circular plates were introduced in 1999 and promoted as a rapid and more stable method for this procedure. A retrospective chart review was performed on all patients who were treated with the Spider Limited Wrist Fusion Plate (Kinetikos Medical Inc., San Diego, CA). Sixteen patients were identified and followed clinically and with X-rays for an average of 16 (range 5-38) months. Nine out of the 16 patients (56%) had complications, including non-union (25%), delayed union (6%), dorsal impingement (25%), radial styloid impingement (6%) and broken screws (13%). The purpose of this study was to compare our complication rate using circular plates with published outcomes using traditional methods of fixation: this study identified a significantly higher complication rate and lower union rate using circular plate fixation for four-corner arthrodesis compared with previously published techniques.

A review of neurological disorders presenting at a paediatric neurology clinic and response to anticonvulsant therapy in Gambian children.

A clinical review of 128 children presenting at the paediatric neurology clinic of the Royal Victoria Hospital, The Gambia was conducted between July 2001 and January 2002. The aim was to assess the spectrum and burden of neurological disease presenting at this tertiary-level clinic and to evaluate the effectiveness of anticonvulsant therapy. The principal clinical diagnoses most frequently made were seizures (57%), neuromotor problems (15%) and developmental delay (11%). Many children also had associated developmental delay or learning difficulties (55%), speech and language problems (42%) and physical disability (36%). Although 65% were considered to need assistance in the community, only 11% were receiving such help. There were 73 children with seizures, 80% of whom had a greater than 50% reduction in seizure frequency following the start of simple anticonvulsant medication. Of the children who had experienced more than 100 convulsions during the previous year, only 50% responded similarly to treatment. This review emphasises the need for improved community services and accessible medical care for children with neurological problems in West Africa.

Type A allatostatins from Drosophila melanogaster and Diplotera puncata activate two Drosophila allatostatin receptors, DAR-1 and DAR-2, expressed in CHO cells.

The type-A allatostatins A (AST-A) are a group of insect peptides with a common C-terminal motif Y/FXFGL-NH(2). The existence of at least four putative type A Drosophila melanogaster ASTs (called type A drostatins or DST-As) has been predicted from the sequence of a recently cloned DST-A preprohormone [C. Lenz et al. (2000) Biochem. Biophys. Res. Commun. 273, 126-1131]. SRPYSFGL-NH(2), (DST-3A), the only DST isolated from Drosophila so far, activated the first cloned DST-A GPCR (DAR-1) [N. Birgül et al. (1999) EMBO J. 18, 5892-5900]. A newly cloned orphan Dm GPCR, which shares 47% overall and 60% transmembrane region sequence identity with DAR-1, was classified as a second putative Dm DST-A receptor (DAR-2) [C. Lenz et al. (2000) Biochem. Biophys. Res. Commun. 273, 571-577]. Although activation of DAR-2 by DSTs has been postulated, no experimental evidence for that has been presented to date. In this study, we expressed both DAR-1 and DAR-2 in CHO cells and used a GTPgammaS and a Ca(2+) mobilization assay for pharmacological evaluation of the receptors. Synthetically prepared DST-As, as well as selected Diplotera punctata (cockroach) ASTs, activated DAR-1 and DAR-2 in both functional assays indicating ligand redundancy and cross species activity. Cell pretreatment with pertussis toxin led to some differences in the nature and magnitude of signaling pathways at the DAR-1 and DAR-2 receptors, suggesting possible differential coupling to cellular effector system(s) and distinct biological functions of each receptor in vivo.

Life expectancy in the Marfan syndrome.

Data reported in 1972 indicated that lifespan in patients with the Marfan syndrome is markedly shortened, and that most deaths are cardiovascular. This study was performed to determine whether survival in the Marfan syndrome has changed since 1972, and to discern whether treatment (medical or surgical) has altered prognosis. Survival curves were generated on 417 patients from 4 referral centers, with a definite diagnosis of the Marfan syndrome. Birth date, age at death, cardiovascular surgery, or treatment with beta blockers, or any combination of these, were included in the analysis. Forty-seven of 417 patients died. Mean age at death (41 +/- 18 years) was significantly increased compared with age in 1972 (32 +/- 16 years, p = 0.0023). Median (50%) cumulative probability of survival in 1993 was 72 years compared with 48 years in 1972. Of 112 surgically treated patients, 10-year probability of survival was 70%. Patients undergoing surgery after 1980 enjoyed significantly increased survival than patients who had undergone operation before 1980 (p = 0.008). In conclusion, life expectancy for patients with the Marfan syndrome has increased > 25% since 1972. Reasons for this dramatic increase may include (1) an overall improvement in population life expectancy, (2) benefits arising from cardiovascular surgery, and (3) greater proportion of milder cases due to increased frequency of diagnosis. Medical therapy (including beta blockers) was also associated with an increase in probable survival.