Prosthetics and Orthotics International

Benchmark data for lower limb amputees is often limited to young subjects who have had their amputations as the result of trauma. The majority of trans-tibial amputees rehabilitated are, however, elderly vascular amputees who may have different gait characteristics than their younger counterparts. Without biomechanical analyses to provide such benchmark data for this group it is not possible to compare the effects of different rehabilitation programmes, gait training regimens, or prosthetic devices.

Twenty elderly vascular trans-tibial amputees rehabilitated at The Queen Elizabeth Centre, Ballarat, Australia and at least six months post-amputation were measured in respect of kinetic and kinematic parameters, and relationships between gait speed, consistency, and function were demonstrated. Further, an unexplained vertical ground reaction force pattern was demonstrated in faster, more functional amputees.

Standing balance measured as sway and standing time both on one and two legs, was studied by use of a stable force platform (Kistler) in 36 patients aged 48–87 years with trans-tibial amputation and 27 healthy subjects matched for age. The aim of the study was to compare postural function in standing in two groups with unilateral trans-tibial amputations, separating vascular disease from trauma. Results revealed that the vascular group had a significantly increased sway in the lateral direction compared with the healthy group, when standing on both feet close together for 30 seconds, looking straight ahead or blindfolded (p values ranging from 0.003 to 0.02). In the sagittal direction the trauma amputees had a significantly decreased sway when looking straight ahead, compared to the vascular and healthy groups (p values = 0.03). No significant differences in the lateral or sagittal direction were seen among the three groups when comparing standing on one leg. There was a significant difference, however, in the standing time in the one-leg standing test of the vascular group when compared with the trauma and healthy groups (p values ranging from 0.0009 to 0.02). In contrast to the vascular group, all subjects in the trauma and healthy groups from 48 to 59 years could stand on the healthy leg for 30 seconds when looking straight ahead, and from 60 to 79 years they could stand for 5 seconds. None in the vascular or trauma group older than 80 years could stand on the healthy leg for 5 seconds. The standing balance of the vascular amputees was found to be inferior to that of the trauma amputees. In conclusion, vascular and trauma trans-tibial amputees should not be considered as an entity in test situations or rehabilitation programmes.

An analysis of 200 patients with congenital limb deficiency who attended the Artificial Limb Centre, Pune from January 1984 to April 1990 is presented. This group is representative of the congenital limb deficient population of the country. The commonest deficiencies were transverse phalangeal total/partial deficiency and transverse forearm partial deficiency (below elbow) in upper limbs, whereas transverse metatarsal total/partial deficiency and transverse leg partial deficiency (below knee) were commonest in lower limbs. Transverse forearm partial deficiency was more common in female, while transverse leg partial deficiency was more common in male children, 16 patients did not require any treatment, 6 needed only surgical correction. Some 30 patients needed surgery before prosthetic fitting, while 148 patients required only prostheses. Some 68% of patients achieved satisfactory to excellent results; 18% showed poor rehabilitation. No definitive cause for the deformities could be isolated; however, many parents believed that possible exposure to the eclipse during pregnancy was the cause of the deficiency. The eldest child was most affected.

The purpose of this pilot investigation was to develop a method to test the influence of specific prosthetic features in preventing trans-tibial amputees from walking like able-bodied subjects. An able-bodied subject was fitted with a patellar-tendon-bearing orthosis incorporating several features of an amputee's prosthesis. Kinetic, kinematic and metabolic data were collected as features were systematically removed from the orthosis. While wearing the orthosis the gait of the able-bodied subject closely simulated trans-tibial amputee gait kinematically, kinetically and metabolically. Although it was obvious that the various prosthetic features influenced the kinetics and kinematics of gait, they were difficult to quantify with only a single subject. However, the two features which appeared to have the largest influence in preventing trans-tibial amputees from walking like able-bodied subjects were patellar tendon loading and a solid ankle.