Statistical Observation and Surgical Method for the Improvement of Claw Hand in Leprosy

Out of 964 patients housed in the Oku Komyoen (a leper house) the author selected 500 patients at random for the statistical observation. They were consisted of 312 males (62.4%) and 188 females (37.6%), whose age ranged from 19 years to 78 years old and most of them were in the ago range between 31 to 50 years old, occupying about 50 per cent of the total. The type of disease can be classified somewhat similar to the classification reported by Ikeda. Those who had claw hand at the onset of leprosy occupy 9.6 per cent, and the claw hand can be seen in 90 per cent of patients 30 years after the onset of the disease. In 37 per cent no claw hand occurred, while in 63 per cent claw hand appeared: and most of them were bilateral. Sensory disturbance can be found in 82 per cent, and the majority of them show peripheral disturbance but some have disturbance in the trunk. Those with the disturbance in ulnar nerve occupy the greatest population, reaching as much as 78.3 per cent. When the grade of claw hand is classified into three degrees, the degree I occupies 13 per cent: the degree II 20 per cent: the degree III 29 per cent: and the rest with normal hand or with fingor defect occupies 38 per cent. The disturbance of opposition of the thumb can be observed in 50 per cent, and 45 per cent of them can not make the thumb-to-finger movement. Those with normal opposition amount to 48 per cent while finger defect can be found in 2 per cent. Disturbance in the finger-to-finger movement can be observed in 52 per cent, surpassing the number of those with claw hand, and those with complete inability to make finger-to-finger movement reach as high as 57 per cent. Those with normal reflex amount to 41 per cent. For the determination of the degree of amyosthenia different muscles were classified according to different bands and Daniels' test for muscle force was conducted. The one that is attacked severest is the interosseal muscle of the small finger eminence of the hand, followed by intorosseal muscle of thumb eminence, lumorical muscle, and flexor carpi ulnaris in the order mentioned. The paralysis of flexor digitorum profundus as well as of m. flexor digitorum sublimis of the small and middle fingers can be observed in many. These points must be borne in mind when the operation is performed for the improvement of claw hand. As for the skeeze dynamometer test the author employed sponge method. It seems that the sponge method is excellent to test the patient's grasping power, as it represents actual skeezing force of the patient.The operation for the improvement of amyosthenia was performed on 39 patients to the total of 168 fingers, and excellent results were obtained practically in all of them. As for the operation of thumb to finger movement Bunnell's method is modified in such a way that a hole is drilled through bone and interruted suture is made so that the proxi mal phalanx of thumb is fixed more firmly and also the tension of tendon is improved. As for the distal phalangeal flection of the thumb during this fixation the tension of extensor longus digitorum muscle of the thumb is increased and its flection is modified by hooking one end of the tendon to the tendon of extensor longus digitorum muscle. In this manner six out of 11 cases showed good results. However, this fixation method occasionally brings about over extension or the disturbance in flection of phalangeal joints of the middle finger so that it must be compared with the method of using the short abductor muscle of thumb as recently reported by Flynn and must be modified appropriately. In case the tendon is passed under flexor carpi ulnaris, although it is not absolutely necessary, there is apt to occur the paralysis of this muscle as high as in 36 per cent. Therefore, it will be advisable to make pulley here. The operation for claw hand was performed on 132 fingers, and all yielded satisfactory results. In contrast to Bunnell's method, m. flexor digitorum is sutured only to lig. collaterale radiale of each finger, and no impairment by this method can be encountered after the opera tion. For the small finger the suture to lig. collaterale ulnaris was attempted, but as all the three case developed abduction in small finger after the operation. We make it a rule now to suture to the radial side. Because of the peculiar nature of leprosy it is necessary to perform the operation atrau matically, and the movement training befor and after the operation as well as rehabilitation must be conducted appropriately without any undue haste and for a considerable length of time.