The Impact of Dividing the Flexor Tendon Pulleys on Tendon Excursion and Work of Flexion in a Cadaveric Model.

PURPOSE: The A2 and A4 pulleys of the flexor tendon system have traditionally been considered critical components of efficient digital flexion. This dogma has recently been challenged. Using fresh human cadaveric hands and a model to measure force and excursion, we sought to clarify the clinical importance of releasing different pulleys. METHODS: Combinations of A1, A2, and A4 pulleys were released on the index, middle, ring, and little fingers of fresh, cadaveric hands. The excursion was measured as the distance the tendon was pulled by the motor to achieve palm touchdown. The force applied by the motor was constant (25 N); work was derived from the product of force and excursion (distance). The change in excursion and work needed to achieve palm touchdown before and after pulley release was measured. Excursion varies among digits and specimens at baseline; therefore, the percentage change from the intact state was used to compare groups. We compared A2 versus A1, A4 versus A1, A4 versus A2, A1 + A2 versus A2, and A1 + A4 versus A4. RESULTS: Isolated A2 or A4 release had the greatest individual impact on the excursion (4.77% ± 1.52% and 3.88% ± 1.93%, respectively). When A1 was released with A2 (9.90% ± 2.52%), the additional impact on the excursion was significant; however, when A1 was released with A4 (2.63% ± 2.81%), the impact was marginal. No clinically or statistically significant change in the work of flexion was detected. CONCLUSIONS: A1 release was clinically significant when added to A2 release but not when added to A4 release. Sacrifice of the A2 and A4 pulleys resulted in a statistically significant, but clinically negligible, difference in flexor tendon excursion. These data suggest that the A1 pulley should be preserved when other proximal pulley components are likely to be compromised. These data also add further support to the concept that the A2 pulley or the A4 pulley can be released as needed for optimal tenorrhaphy. CLINICAL RELEVANCE: During flexor tendon repair, the length of contiguous pulley release may have more impact on final tendon excursion than which specific pulleys are released.

Treatment of Refractory Radial Sensory Neuroma With Function-Sparing Targeted Muscle Reinnervation to the Extensor Carpi Radialis Brevis.

The radial sensory nerve can be injured during many common procedures, including intravenous cannulation, first extensor compartment release, and radial-sided wrist surgery. Injury to the nerve may result in neuroma formation that can lead to chronic and debilitating pain. Nonsurgical treatments and surgical interventions, including excision of the neuroma and burying the nerve into local muscle, are frequently ineffective. Here, we present a technique for treating recalcitrant neuromas of the radial sensory nerve with targeted muscle reinnervation to a redundant motor nerve branch of the extensor carpi radialis brevis.

Impairment of endothelium-dependent dilation is an early event in children with familial hypercholesterolemia and is related to the lipoprotein(a) level.

Familial hypercholesterolemia is associated with premature atherosclerosis. Since endothelial dysfunction is an early event in atherogenesis, we used a noninvasive method to assess endothelial function in the systemic arteries of 30 children aged 7-17 yr (median 11) with familial hypercholesterolemia (2 homozygotes, 28 heterozygotes, total cholesterol 240-696 mg/dl) and 30 healthy age- and sex-matched controls. Using high resolution ultrasound, the diameter of the superficial femoral artery was measured at rest, in response to reactive hyperemia (with increased flow causing endothelium-dependent dilation), and after sublingual glyceryltrinitrate (causing endothelium-independent vasodilation). Flow-mediated dilation was present in the controls (7.5 +/- 0.7%) but was impaired or absent in the hypercholesterolemic children (1.2 +/- 0.4%, P < 0.0001). Total cholesterol was inversely correlated with flow-mediated dilation (r = -0.61, P < 0.0001). In the hypercholesterolemic children, flow-mediated dilation was inversely related to the lipoprotein(a) level (r = -0.61, P = 0.027) but not to other lipid fractions. Glyceryltrinitrate-induced dilation was present in all subjects but was lower in the hypercholesterolemia group (10.0 +/- 0.6% vs 12.4 +/- 0.8%, P = 0.023). Thus, impaired endothelium-dependent dilation is present in children with familial hypercholesterolemia as young as 7 yr of age and the degree of impairment is related to the lipoprotein(a) level.

The entry of sodium into human red blood cells in vivo.

The kinetics of sodium, movement into human red blood cells has been studied in vivo with (24)Na. When human serum albumin(-131)I is used to measure the percentage of plasma trapped in the packed red blood cells after centrifugation, approximately 30 % of red blood cell sodium is found to equilibrate immediately with plasma. It is concluded that this immediately exchangeable compartment of red blood cell sodium is an experimental artefact, associated with the use of labeled albumin for measuring plasma trapping. This immediately exchangeable fraction disappears when sucrose-(14)C is used to measure plasma trapping. The experimental results were examined by compartmental analysis, using an analogue computer. The results obtained, when plasma trapping was measured with sucrose-(14)C could be simulated by the use of models containing two compartments, arranged in series or in parallel. The errors of the techniques used and the possible physical basis for the results are discussed.

Augmentation of macrophage phagocytic activity by cell-free extracts of selected lactic acid-producing bacteria.

Oral and intraperitoneal administration of lactic acid-producing bacteria can significantly augment the immune response in murine models; however, the immunopotentiating effects in these studies differ significantly. Murine macrophagelike cell line J774 was cultured in the presence of cell-free extracts of Lactobacillus acidophilus and Bifidobacterium longum, and the effect on macrophage function was evaluated by measurement of synthesis of selected enzymes and their ability to take up either acrylamide particles or live Salmonella typhimurium. Lysozyme activity of J774 cells was significantly decreased by cell-free extracts of B. longum, but not of L. acidophilus, whereas extracts of both strains induced morphological changes and significantly enhanced phagocytosis of inert particles or viable Salmonella. Whole cell extracts of lactic acid-producing bacteria are therefore capable of altering macrophage function in a strain-dependent manner.

Treatment of hypernatraemic dehydration in infancy.

Thirty-eight infants with severe hyperosmolar dehydration and hypernatraemia were treated, using three regimens of intravenous fluids: A. 1/2 normal saline, given fast; B.1/2 normal saline given slowly; C. 1/5 normal saline. 28 of the infants were studied in a treatment trial, and it is concluded tha 0-18% saline in 4-3% dextrose, with the early addition of potassium given at a rate of 100 ml/kg estimated rehydrated weight per 24 hours gives satisfactory rehydration within 48 hours, with little risk of convulsions.

Effect of a single oral dose of prednisolone in acute childhood asthma.

140 children of 184 with acute asthma entered a randomised double-blind trial of oral prednisolone (n = 67) compared with placebo (n = 73) administered soon after admission. The dose of prednisolone was 30 mg in children under 5, otherwise 60 mg. All children also received salbutamol. All had moderate or severe dyspnoea. Initial evaluation was similar for both groups. On reassessment after a few hours 20 children in the prednisolone group were fit for discharge compared with only 2 in the placebo group. There were no early reattendances. Children remaining in hospital had a shorter median duration of stay and were less likely to require further steroid therapy if they had initially received prednisolone. In acute asthma the prompt use of a single dose of oral prednisolone can reduce morbidity and the need for hospital care.

Intravenous feeding of young infants with persistent diarrhoea.

42 infants with persistent diarrhoea were fed intravenously using a simplified regime based on Intralipid and an aminoacid, Fructose and ethanol solution. Peripheral veins were used for up to 56 days, and with scalp veins complications were few and minor. The use of arm and leg veins caused more frequent local problems and is not advised. Central venous lines became necessary in 5 infants, and 3 developed septicaemia. The regime was well tolerated with adequate weight gain when intake was adjusted to the infants' needs. Rates of infusion of 1 g Intralipid/kg hourly over 2 hours and up to 1 g fructose/kg hourly over 14 hours did not cause persistent lipaemia (except transiently in 2 infants) nor metabolic acidosis. Infants must be fully rehydrated with correction of acidosis and electrolyte imbalance before starting intravenous feeding, or acidosis and dehydration from osmotic diuresis may occur. Intravenous feeding should be started gradually and cautiously in severely malnourished infants, and should not be used where liver function is abnormal.

An approach to patient care classification.

Employing the principles of progressive patient care and using data obtained from charts, nurses and resident physicians, 265 patients on the wards of a teaching hospital were classified into one of six optimal levels of care by the resident physicians and also by an outside observer. It was assumed that facilities for the three alternatives to general hospital care, i.e. long-term hospital care, nursing care and sheltered care, were available in the community. It was also assumed that socio-economic factors presented no barrier to hospital discharge.The outside observer allocated 96 patients, approximately one-third, to the alternative facilities outside the general hospital. Those factors found to have statistically significant effects on assigned levels of care were the diagnoses, length of stay, region of residence, bed status, extent of nursing care, hospital service and discharge status. The residents allocated 60 patients, approximately one-fifth, to alternative facilities.The extent of agreement between the residents and the outside observer reached 81% for those to alternate versus general hospital care.This method could be used by nurses and residents to screen out those most suitable for care in alternate facilities.