Sport injuries aligned to peak height velocity in talented pubertal soccer players.

In young athletes, demands of sports are superimposed on normal growth and maturation. It has been suggested that this causes a temporarily increased vulnerability for injuries. We followed 26 talented soccer players (mean age 11.9±0.84 years) longitudinally for 3 years around their adolescent growth spurt, called Peak Height Velocity, to identify differences in number of traumatic and overuse injuries and days missed due to injuries. Peak Height Velocity was calculated according to the Maturity Offset Protocol. The number of injuries was calculated for each player per year. A repeated measurement analysis showed that athletes had significantly more traumatic injuries in the year of Peak Height Velocity (1.41) than in the year before Peak Height Velocity (0.81). A moderate effect size of 0.42 was found for the difference in number of overuse injuries per player per year before (0.81) and after Peak Height Velocity (1.41), respectively. Finally, a moderate effect size of 0.55 was found for difference between days missed due to injuries before (7.27 days per player per year) and during Peak Height Velocity (15.69 days per player per year). Adolescent growth spurt seems to result in increased vulnerability for traumatic injuries. Afterwards athletes seem to be susceptible to overuse injuries.

Burst fractures of the thoracolumbar spine: changes of the spinal canal during operative treatment and follow-up.

Although multiple studies have concluded operative decompression of a traumatically narrowed spinal canal is not indicated because of spontaneous remodeling, instrumental decompression is frequently used as part of the operative treatment of spinal fractures. To investigate the process of remodeling, we studied the diameter of the spinal canal in 95 patients with burst fractures at the thoracolumbar junction (T9-L2). To measure and compare the spinal canal's diameter we used either computed tomography (CT) scans or radiographs, made preoperatively, postoperatively, after 9 months and after 24 months. In lateral plain radiographs we found that the initial percentage of cases with bony canal narrowing preoperatively of 76.5 was reduced to 18.4% postoperatively, to 8.2% at 9 months, and to 2.4% at 24 months. In CT scans in a selection of patients, the mean residual diameter of the spinal canal was 53% preoperatively and 78% at 24 months. The posterior segmental height increases during operation and decreases in the respective periods after operation. So ligamentotaxis can only play a role in the perioperative period. We conclude that a significant spontaneous remodeling of the spinal canal follows the initial surgical reduction. Two years after operation, bony narrowing of the spinal canal is only recognizable in 2.4% of the patients on plain lateral radiographs. The remodeling of the spinal canal can be seen on plain radiographs, although not as accurately as on CT scans.

Thoracolumbar spinal fractures: segmental range of motion after dorsal spondylodesis in 82 patients: a prospective study.

In order to study the effect of dorsal spondylodesis on intervertebral movement in patients treated for thoracolumbar fractures, we measured the sagittal range of motion (ROM) in the segments above and below the fractured vertebral body 2 years after operation. Between 1991 and 1996, 82 consecutive patients with a fracture of the thoracolumbar spine (T12, L1, L2 and L3) were treated operatively with open reduction and stabilisation using an internal fixator, combined with transpedicular cancellous bone graft and dorsal spondylodesis. Eighteen T12, 42 L1, 17 L2 and 5 L3 fractures were included. The range of motion of two segments above and two segments below fracture level was measured. This was done on plain flexion and extension radiographs. The data were compared to normal values and to the zero distribution with the Kolmogorov-Smimov test. At all fracture levels the ROM of the segment adjacent to the disturbed endplate of the fractured body was zero (K-S test). All other evaluated segments showed significant loss of ROM (P<0.05) compared to normal values, except segment L1-L2 in L3 fractures (P=0.058). Dorsal spondylodesis at the level of the disturbed endplate in thoracolumbar spinal fractures leads to immobility in this segment, measured on flexion-extension radiographs 2 years after primary operative treatment. More than 50% loss of motion in the two adjacent levels is equivalent to complete loss of ROM in a second segment.

Chemical analysis and consistency of faeces produced by captive monkeys (François langurs, Trachypithecus francoisi) fed supplemental fibre.

The effect of additional dietary fibre on the consistency of faeces was studied in a group of four François langurs (Trachypithecus francoisi) kept in Rotterdam Zoo. To increase fibre intake, a diet pellet rich in fibre was offered instead of the usual, commercial primate pellet. This dietary change raised the amounts of hemicellulose and cellulose that were consumed at the expense of non-structural carbohydrates. The experiment had an A1-B-A2 design. Stool quality improved when the high-fibre pellet was fed. The monkeys produced somewhat more faecal dry matter and the faeces contained markedly more non-structural carbohydrates and less crude fibre when the high-fibre pellet was fed. The percentage of water in the faeces was slightly lower when the high-fibre diet was offered. We speculate that the extra fibre was partly fermented and that the breakdown products were recovered in the carbohydrate fraction of faeces. These breakdown products might have a superior water-binding capacity, leading to well-shaped faeces. This study showed that François langurs have the capacity to digest dietary fibre, as has been demonstrated earlier for other species of leaf-eating monkeys.

Residential mental health assessment within Dutch criminal cases: a discussion.

In Dutch criminal cases in which doubts arise about the defendant's mental health, a forensic assessment will be requested. This is provided either by the multidisciplinary staff of residential clinics who conduct forensic evaluations for the court, or by mental health professionals contracted on a part-time basis by district courts. This article discusses the procedures applied in such cases as well as the relevant legal provisions. It focuses particularly on the clinical observation, evaluation, and reporting that is carried out over a number of weeks in the residential setting of the Pieter Baan Centrum. Specific attention is paid to procedures applied in this clinic. It is suggested that Dutch procedures for the use of mental health expertise can best be characterized by three aspects: multidisciplinary observation and reporting, the use of a sliding scale for indicating degree of responsibility, and, finally, the involvement and payment of experts by the state as such, rather than by the prosecution and/or the defense.

The difference in blood pressure between upper arm and finger during physical exercise.

A new apparatus which measures the blood pressure in the finger continuously and yet not invasively was tested for its usefulness during exercise. It was compared with upper arm measurements in 23 volunteers during prolonged bicycle ergometry. Simultaneously, a pulse plethysmogram was recorded from another finger of the same arm, whereas in six additional volunteers Doppler measurements were carried out on the radial artery. The results show that finger systolic pressure ceased to rise at about 40% of maximal exercise; the difference with the continuously rising systolic pressure in the upper arm becoming significant at 140 W. At the same time the amplitude of the finger plethysmogram became significantly higher than its initial value, indicating distinct cutaneous vasodilation, whereas the volunteers also became hot and started to perspire. However, the radial artery 'flow', deduced from the Doppler measurements, did not change significantly during exercise. It increased sharply and markedly in the cooling down period. Simultaneously with this increase in flow, HR and both systolic blood pressures fell drastically whereas the plethysmographic amplitude remained about stable at its raised level. The results fit in with the idea that a compromise is achieved between the need for muscle activity and the need for temperature regulation. It is concluded that the Finapres functions well during exercise, but that the systolic pressure in the finger is not representative for its more central counterpart during cutaneous vasodilation. It is argued that opening up of AVAs may contribute to this pressure effect.

The effect of ketamine on the peripheral circulation: a possible sympathetic ganglion blocking effect.

The effects of induction of anaesthesia, endotracheal intubation and surgical stimuli on the systemic and peripheral circulations were studied in three groups of patients. In group KA (n = 8) anaesthesia was induced with ketamine (2 mg kg-1) and alcuronium, supplemented by N2O-O2 alone; in group KAH (n = 9) 0.5% halothane was added to the N2O-O2; and in the control group TAH (n = 8) anaesthesia was induced with a sleep dose of thiopentone and alcuronium, supplemented by N2O-O2 and halothane. The circulation in the finger was monitored by photo-electric plethysmography. Induction produced a significant pressor response in both ketamine groups, but not in the TAH group, while the finger plethysmogram demonstrated peripheral vasodilatation in all three groups. Intubation, on the other hand, elicited a significant pressor response in the TAH and in the KAH group but not in the KA group. The finger plethysmogram, however, always showed peripheral vasoconstriction during intubation in the thiopentone group (TAH) but never in either of the ketamine groups. The results suggest that ketamine exerts a peripheral ganglion blocking effect.

[The treatment of gastroesophageal reflux using the Kaunitz technic]. / De behandeling van gastro-oesofagiale reflux bij middel van de Kaunitz techniek.

The Kaunitz' procedure in the surgical treatment of gastroesophageal reflux associated with a hiatal hernia. In patients with pathological gastroesophageal reflux associated with a hiatal hernia, simple repositioning of the lower esophageal sphincter (L.E.S.) without fundoplication can restore the competence of the L.E.S., provided there is adequate mobilisation of the esophagus and fixation to strong tissues. The procedure proposed by Kaunitz consists of a left thoracotomy, with fixation of the gastroesophageal junction to the diaphragm. In the period May 74-May 83 we performed the procedure on 85 patients. There was no operative mortality and a low early complication rate. All but one patient showed a good repositioning on the postoperative barium swallow and improved dramatically, with complete cessation of reflux symptoms. Seventy-eight patients (92,8%) are followed up regularly by means of a standard questionnaire, barium swallow and esophagoscopy. At this stage of the study, with follow-up periods ranging from 6 months to 9 years, 65 patients (83,3%) show an excellent result, six (7,7%) are greatly improved, with disappearance of the preoperatively existing esophagitis, but keep some mild residual reflux symptoms. In one patient repositioning was impossible. Six recurrences were noted, four of them in patients operated during the early period of our experience with the Kaunitz technique. This simple and effective procedure is a valuable alternative in the surgical treatment of pathological gastroesophageal reflux.

Photo-electric plethysmography as a monitoring device in anaesthesia. Application and interpretation.

The optical principle of photo-electric plethysmography is described and the clinical significance of changes in the amplitude of the plethysmogram discussed. Physiologically, changes in blood volume pulsations depend on the distensibility of the vessel wall as well as on the intravascular pulse pressure. The importance of both factors in the interpretation of changes in the arterial pulse amplitude is illustrated by examples from 500 continuous recordings. In addition, it is shown that changes in the height of ventilatory waves may be of diagnostic significance.

Comparison of plethysmograms taken from finger and pinna during anaesthesia.

Pulse plethysmograms from finger and pinna were recorded simultaneously during anaesthesia, and marked differences in their response to various stimuli recorded. The differences have been illustrated by a number of examples.

Effects of peripheral vasoconstriction on the blood pressure in the finger, measured continuously by a new noninvasive method (the Finapres).

The authors determined whether vasoconstriction alters the ability of a noninvasive method (Finapres) of continuously measuring arterial blood pressure in the finger to function accurately. They compared the response of the Finapres to blood pressures determined simultaneously by an oscillometric technique (Dinamap) in six anesthetized patients. Vasoconstriction was detected from a photoelectric plethysmogram, which was recorded continuously from an adjacent finger. Vasoconstriction was defined as a decrease in amplitude to less than half of its highest value in one and the same patient. From the 378 paired blood pressure readings obtained in this study, 51% took place in such a vasoconstricted state. The authors found that diastolic and mean blood pressures in the finger were, on the average, 9 mmHg below those in the upper arm and that the systolic pressure was 7 mmHg above that in the upper arm. The authors concluded that the Finapres keeps functioning well during peripheral vasoconstriction and is a recommendable method to monitor arterial blood pressure in the finger.

Effects of peripheral vasoconstriction on the measurement of blood pressure in a finger.

Using noninvasive techniques only, the fall in mean pressure and the pulse amplification between brachial and finger arterial pressure were measured in six anaesthetised female subjects during surgery. Brachial pressure was measured every 2 min with an oscillometric technique. Finger pressure was measured continuously using an arterial volume clamp method. In addition changes in the degree of peripheral vasoconstriction were established on an adjacent finger with a photo reflection plethysmograph. On the average finger mean pressure is 10 mmHg below brachial pressure. The difference tends to decrease with increasing constriction. The change in the difference between full constriction and maximal dilatation is 8 mmHg. The average finger to brachial pulse amplitude ratio changes from 110% at maximal dilatation to 170% at full constriction. Finger systolic pressure overshoot is responsible for the pulse wave amplification. On the average it is + 7 mmHg and ranges between maximal dilatation and full constriction over 26 mmHg. The standard error deviation on the volume clamp method could be established at 5% for mean pressure, about equal to that of the oscillometric technique in the literature.

The origin of inverted waveforms in the reflection plethysmogram.

In reflection plethysmography at the finger inverted pulsewaves are sometimes observed, especially when, during anaesthesia, arterial pressure is measured in the same arm with an inflatable cuff. The origin of this inversion is investigated to two series experiments with volunteers. In the first series of experiments the influence of the pressure in the upper arm cuff was investigated and in the second series the influence of the application pressure of the transducer on the finger. It is concluded that inversion of the pulse waves of the plethysmogram is local phenomenon restricted to the reflection method. It is caused by a relative increase in the optical density of the surrounding tissue in relation to the arterial vessels. In the finger it is brought about by venous engorgement and it is dependent on the applied pressure.

Photoelectric plethysmography--some fundamental aspects of the reflection and transmission method.

In photoelectric plethysmography a distinction is made between the reflection methods. Uncertainties still exist, especially regarding the origin of the reflected signal: some investigators attach quantitative value to the amplitude of the plethysmogram. The various findings are reconsidered. Various fluids are pulsatingly pumped through an in vitro circuit. Flow, pressure and volume pulsations are measured, as is the total light intensity detected by a photoelectric plethysmograph with the small variations caused in it by the pulsations in flow. Both phase and amplitude of the resulting plethysmogram are studied and the results compared with those found in vivo at the fingers and auricles. In vitro, the variations in light reflection are in phase with the volume pulsations: this can only be ascribed to reflection by orienting erythrocytes. In vivo, however, the light reflection, like the light transmission, is in anti-phase with the volume excursions, thus eliminating the determinative effect of light reflection by orienting erythrocytes--the strong reflection from surrounding tissues completely dominates reflection from erythrocytes. Since erythrocytes also have absorptive properties, and the light reflection is in anti-phase with the volume excursions, it is concluded that this absorptivity can manifest itself over the strong reflection from surrounding tissue. In vivo, therefore, the reflection plethysmogram is, in principle, an absorption measurement. The relationship between intensity of detected light and resultant voltage may not be linear: this nonlinearity may not be neglected when amplitude changes are compared. Amplitude changes of different plethysmograms may only be compared quantitatively if there is no difference in their light-voltage relationship.