Abstract

Purpose: Detailed analysis of the gaits of diabetic patients may have the potential of identifying risk predictors with diagnostic utility in high-risk patients, and therefore, lead to interventions that could effectively prevent lower extremity amputation arising from diabetic foot ulcer and gangrene.

Relevance: Identification of high-risk patients prone to foot ulceration, and targeting intervention to arrest the pathophysiological processes could lower the morbidity and mortality rate in this populace.  

Participants/Subjects: Eighty (20 normal, 20 diabetic, 20 diabetics with peripheral neuropathy and 20 diabetics with foot ulcer) subjects were recruited from the University of Nigeria Teaching hospital and other peripheral hospitals, using convenience sampling technique. Their mean age was given as 42.09 ± 10.22 years, 51-88 ± 11.50 years, 43.83 ± 9.26 years and 44.00 ± 8.25 years respectively

Method: - This study utilized a case-control research design. Gait analysis and evaluation was done with subjects ambulating on a plain walkway, 10 metres long, in a remote hospital building, at five self-selected speeds varying from very slow to very fast walking speeds. The mean of two trials was recorded. The mean quantitative gait values of step length and time were obtained and used to calculate the velocity (V), stride length (L), stride frequency (F), stance (ST), swing (SW) and double-support (DS) phases of stride. These were adapted to form the modified velocity field diagram (MVFD). From the MVFD, the load coefficient was determined as the slope of the loading zone and used to calculate the load (weight of the body) transferred to the forefoot (F) and rearfoot (R) during walking, and subsequently, the forefoot-rearfoot (F/R) load ratio. ANOVA test was used to analyze parametrically distributed data. All tests will two one tailed, with alpha set at 0.05.

Results: - F/R  load distribution ratio of 1, 2 and 3, was obtained in the loading zone of the MVFD, for normal subjects/subjects with diabetes, diabetic patients with peripheral neuropathy, and subjects with diabetic foot ulcers, respectively. These load ratios were obtained at a gait efficiency region (GER) of 1.89 velots, 2.25 velots, 2.5 velots and 3.32 velots, respectively.

Conclusions: These results indicate the possibility that a load imbalance between the forefoot and rearfoot was responsible for the diabetic foot ulcer in the affected subjects, hence a F/R ratio of 3. In contrast, a balance in the load distribution was obvious in normal and diabetic subjects, hence a F/R ratio of 1. Thus, for a F/R load ratio of 2 to be recorded in subjects with peripheral neuropathy suggests a forefoot/rearfoot load imbalance whose magnitude is not enough to precipitate foot ulcer. Therefore, it is predicted that foot ulcers in diabetic patients will be precipitated at a F/R load ratio > 2 and a GER > 2.5 velots

Implications: Early detection of diabetic patients at the risk of ulceration before it occurs can help target intervention to prevent its occurrence since it is also amenable to Physiotherapy intervention through load redistribution. Invariably, it emphasizes the relevance/indispensible role of Physiotherapy in providing care for diabetic patients

Keywords: forefoot-rearfoot load imbalance, diabetic foot ulcer, modified velocity field diagram