Upper limb reduction deficiencies in Swedish children : classification, prevalence and function with myoelectric prostheses

Abstract: Upper limb reduction deficiency (ULRD) is a rare condition that has been known ever since the 6th century B.C. This is a lifelong deficiency which in an afflicted child can lead to practical limitations, social restrictions and physical problems. The overall aim of this research was to increase the knowledge about children with upper limb reduction deficiencies from three perspectives: the deficiencies themselves, the use of prostheses and the well being of the affected children. To validate information regarding ULRD in the Swedish Register for Congenital Malformations (SRCM), all infants reported to this register during 1973-1987 were re-classified according to a more detailed classification. The result was compared with a clinic-based register at the Limb Deficiency and Arm Prostheses Centre in Örebro, Sweden. The findings indicate that SRCM, with its calculated underestimation of 6%, can be used for studying the prevalence of ULRD in Sweden. However, as SRCM is a surveillance register, the quality of some information seems to be low, making detailed description of cases difficult. Use of the population register data for clinical purposes could therefore result in lower validity. Additional information and follow-up of specific cases are therefore recommended.The presence of scoliosis and trunk asymmetry was studied in 60 persons with transverse ULRD. Nineteen persons (31%) had a scoliosis of between 10 and 19º and 30 persons had minor curves of between 5 and 10º. There was a significant correlation between leg length inequality and side of the convexity, with the convexity directed towards the side of the shorter leg in 21 of 28 persons. This indicates that children with transverse ULRD may have a transient scoliosis of postural origin of no clinical significance.A new observation-based test, the Assessment of Capacity for Myoelectric Control (ACMC), which measures a person’s capacity to control a myoelectric prosthetic hand during the performance of ordinary daily tasks, was developed. Occupational therapists completed 210 assessments of 75 persons. Rasch rating scale analysis was used for validation and reliability estimations. The results demonstrate internal scale and person response validity.The external reliability of ACMC was established by scorings from three raters with different degrees of experience on 27 videotapes of client performance. The major finding in this study was that in order to obtain reliable measures from the ACMC the raters have to have some experience of this group of clients. Until the ACMC can adjust for rater severity, the same rater should perform the ACMC when it is used for follow-up or clinical trials.In a study of 62 children we found that, overall, children with ULRD who have been fitted with a myoelectric prosthetic hand are just as well adjusted psychosocially as their able-bodied peers. There are indications, however, of social stigmata related to the deficiency which have to be considered differently in boys and girls. Most children who have been provided with a myoelectric prosthesis at an early age continue to use the prosthesis.