Monitoring distances travelled by horses using GPS tracking collars.

OBJECTIVE: The aims of this work were to (1) develop a low-cost equine movement tracking collar based on readily available components, (2) conduct preliminary studies assessing the effects of both paddock size and internal fence design on the movements of domestic horses, with and without foals at foot, and (3) describe distances moved by mares and their foals. Additional monitoring of free-ranging feral horses was conducted to allow preliminary comparisons with the movement of confined domestic horses. PROCEDURES: A lightweight global positioning system (GPS) data logger modified from a personal/vehicle tracker and mounted on a collar was used to monitor the movement of domestic horses in a range of paddock sizes and internal fence designs for 6.5-day periods. RESULTS: In the paddocks used (0.8-16 ha), groups of domestic horses exhibited a logarithmic response in mean daily distance travelled as a function of increasing paddock size, tending asymptotically towards approximately 7.5 km/day. The distance moved by newborn foals was similar to their dams, with total distance travelled also dependent on paddock size. Without altering available paddock area, paddock design, with the exception of a spiral design, did not significantly affect mean daily distance travelled. Feral horses (17.9 km/day) travelled substantially greater mean daily distances than domestic horses (7.2 km/day in 16-ha paddock), even when allowing for larger paddock size. CONCLUSIONS: Horses kept in stables or small yards and paddocks are quite sedentary in comparison with their feral relatives. For a given paddock area, most designs did not significantly affect mean daily distance travelled.

Characterization and use of an optical fiber interferometer for measurement of the electric wind.

An optical fiber interferometer of the Mach-Zehnder type has proved to be a convenient and accurate method for measuring the electric wind in the active region of a corona discharge. The technique relies on the cooling effect of the wind on a small heated region of one arm of the interferometer, which has been remotely heated with an infrared CO(2) laser beam. Wind speeds of up to 5.5 m s(-1) have been measured near the generation region, and by the use of a mesh electrode, the wind has been detected on the axis up to 0.5 m away from the gap. A number of characterization experiments that show the interferometer to be a useful diagnostic tool in the quantitative analysis of the CO(2) laser beam have also been carried out, and good agreement between experimental results and theoretical calculations based on a simple heat-power balance equation for the fiber exists.

The treatment of longitudinal radial deficiency.

Absence of the radius is the commonest of the longitudinal deficiencies but is itself quite an unusual congenital anomaly. No one surgeon is likely to encounter the condition more than once or twice in a career and there is a strong case for congenital upper limb conditions to be collected into special clinics. The pathology and methods of surgical treatment are reviewed. It is a difficult condition to treat but there is no doubt that function and appearance can be improved (Pulvertaft, 1973). Pollicisation of the index finger should be considered and can often greatly improve the function.

A new prosthesis for the upper limb.

We describe the development of a body-powered upper limb prosthesis fitted with a cosmetic functioning hand. The features and advantages of the new design--the PMR (Princess Margaret Rose) prosthesis--are discussed and the clinical results in 15 patients fitted with the prosthesis after above-elbow amputation are described.

Ulnar instability of the metacarpophalangeal joint of thumb.

A method of reconstruction of the long standing rupture of ulnar collateral ligament of the thumb is described. Its advantage is the tightness with which the tendon used for repair can be sutured to achieve maximum stability. This has been used in eight patients in the past four years and provided a stable and painless thumb.

A wrist-powered hand prosthesis.

This paper describes a prosthesis for patients who have had a partial amputation of the hand, or who have congenital absence of all or part of the hand. The prosthesis incorporates a new concept whereby the grip is operated by flexion and extension of the wrist. A covering for the prosthesis has been developed using a silicone polymer which produces a lifelike flexible glove. Thirteen patients have so far been fitted with this type of prosthesis, which can give good function and cosmesis.

A study of liver microsomal enzymes in rats following propoxur (Baygon) administration.

Groups of rats were given either propoxur, were left as untreated controls, or were given phenobarbital, DDT, chlordane or toxaphene which are known to induce liver microsomal detoxification enzymes. Microsomal enzyme activity was measured by testing the ability of liver homogenates to degrade EPN (O-ethyl O-(4-nitrophenyl) phenylphosphonothioate) to p-nitrophenol. The activity of aminopyrine-N-demethylase, cytochrome P-450 and p-nitroanisole-O-demethylase in liver homogenates of rats receiving propoxur was measured. Liver microsomal detoxification enzymes were not induced by propoxur exposure.

Dislocations of the lunate with and without fracture of the scaphoid.

A review of 61 patients with dislocation of the lunate (some with and some without fracture of the scaphoid) showed that the majority had satisfactory results at an average follow-up of three and a half years. Most patients with a simple dislocation had a good or satisfactory result; radiological instability was noted in a quarter of the wrists but was not often associated with symptoms. Two-thirds of the patients with an associated fracture of the scaphoid had a good or satisfactory result. Immediate percutaneous wire fixation of the reduced scaphoid, whether it is fractured or not, is the best way of maintaining normal anatomical relationship while the ligaments and fracture heal; this may further improve the prognosis. In most cases extreme dorsiflexion of the wrist appeared to be the mechanism of injury.

"Rugby finger"--avulsion of profundus of ring finger.

The results of tendon grafting following avulsion of the profundus tendon to the ring finger ("Rugby finger") are described. Function in the hand was improved in all cases and this is a method of treatment which should be considered by the surgeon experienced in tendon grafting in those patients who are young and well motivated. The exact reason for the common involvement of the ring finger is not clear but the unique lumbrical origin from that profundus may be an important factor tethering the tendon in the palm, and this is suggested as the possible cause of this injury.

Some thoughts on the current state of treatment of the upper limb in traumatic tetraplegia.

Traumatic tetraplegia often affects healthy young men. The medullary lesion is located at C6 in 75% of cases. The author on the basis of 20 years of experience believes it possible to improve independence and life quality by surgical procedures such as tendon transfers, which are the most often used, for restoring two important functions: active elbow extension and active hand grip. The restoration of elbow extension is accomplished by Moberg's procedure of transferring the posterior tendon of the deltoid onto the triceps. The results are very satisfactory. To restore hand grip the author makes use of the first radial tendon transferred onto the deep common flexor, and for the thumb, the long supinator onte the long flexor of the thumb. Definite functional improvement was found in 33 of 45 cases.

Triphalangeal thumb and five-fingered hand.

A plea is made for greater recognition of the differences between triphalangeal thumb and five-fingered hand. Both conditions can benefit from surgical management but the methods required are entirely different.