Progression and distribution of plantar pressure in Type 2 diabetic patients.

The aim of this prospective 4-yr study was to analyse changes in mean plantar pressure (PP) over time and local shifts of maximal PP in Type 2 diabetic patients. One-hundred fifty-five Type 2 diabetic patients (age 58.9 +/- 7.5 yr, diabetes duration 11.0 +/- 7.6 yr, baseline HbA1c 9.6 +/- 1.6%) were examined with regard to foot abnormalities, neuropathy and measurement of PP during walking (pedobarography). They were assigned to two subgroups, namely normal PP (n=94) and elevated PP (n=57). Patients with an abnormal mean PP did not significantly differ from subjects with a normal PP with regard to sex, age, duration of diabetes and HbA1c. With the exception of the hallux, the mean PP was significantly increased in both groups at all other plantar sites. Maximum PP was located below the metatarsal heads (MTH) 2-5 and significantly increased from baseline (median, lower/upper quartile: 475, 355/715 kPa) to the end of the study (540, 435/749; p<0.0001). On the other hand, PP was normalized in 17 subjects (29.8%) who had an elevated PP at baseline. Furthermore, we observed a local shift in maximal PP towards the MTH 2-5 region. The percentage of patients who had their highest PP under MTH 2-5 was increased from 54.0% at baseline to 61.1% at the end of the study. In general, we registered an elevation of PP over time and a centralization towards sites which are generally prone to ulceration.

The value of the Rydel-Seiffer tuning fork as a predictor of diabetic polyneuropathy compared with a neurothesiometer.

AIMS: The aim of the study was to investigate the predictive value of the Rydel-Seiffer tuning fork for detecting diabetic neuropathy and to compare it with an electronic neurothesiometer. METHODS: In 2022 consecutive diabetic subjects, peripheral polyneuropathy was diagnosed by vibration perception threshold (VPT) at the tip of both great toes using a 128-Hz tuning fork and a neurothesiometer, by simple bedside tests and by the presence of neuropathic symptoms. These evaluations were further combined to diagnose peripheral nerve dysfunction (abnormal bedside tests) and symptomatic neuropathy. VPT was also measured in 175 non-diabetic control subjects to define normal values. RESULTS: VPT was normal in 1917 subjects and abnormal in 105 (5.2%) patients when measured by the tuning fork. Patients with an abnormal vibration test were significantly (P < 0.0001) older than subjects with a normal vibration sense, while diabetes duration and HbA(1c) of the former were also significantly elevated. The same was true for the percentages of an abnormal 10-g monofilament test (66.7% vs. 7.2%, P < 0.0001) and a missing Achilles' tendon reflex (68.6% vs. 24.8%, P < 0.0001). Finally, the VPT measured by the neurothesiometer was 2.5 times higher in patients with an abnormal tuning fork test (32.0 +/- 9.8 vs. 12.5 +/- 6.4 V, P < 0.0001). The plot of the difference of both methods against their mean yielded a good agreement of the two VPT measurements, and the tuning fork had a high sensitivity and positive predictive value for the diagnosis of abnormal bedside tests and for symptomatic neuropathy. CONCLUSION: The tuning fork reliably detected peripheral neuropathy in comparison with the neurothesiometer. A tuning fork is a useful screening test for diabetic neuropathy.

Limited joint mobility in selected hand and foot joints in patients with type 1 diabetes mellitus: a methodology comparison.

OBJECTIVES: First to determine the range of motion (ROM) of selected foot and hand joints with a goniometer, 2.) to determine joint limitation by prayer sign and 3.) to compare both methods used. METHODS: Maximal active ROM was measured by goniometry (Method 1) in 50 patients with Type 1 diabetes and in 44 healthy controls, respectively. The lower limits for normal ranges were defined as mean minus 2 SD. To elicit the prayer sign (Method 2) subjects were asked to put their hands together in a praying position with the fingers fanned. The number of missing joint contacts between the fingers was counted and correlated to ROM. RESULTS: The ROM of all joints measured, except that of the thumb, was significantly smaller in diabetic patients than in control subjects. The degree of the prayer sign was well correlated to the ROM of most hand joints, but was solely correlated in feet to ankle ROM. In diabetic patients the prevalence of limited joint mobility (LJM) measured by goniometry ranged from 2 to 20% in hand joints and from 10 to 14% in foot joints. By the prayer sign 33% of the diabetic patients had LJM. CONCLUSION: With both methods, diabetic patients had more limitations in joint motion than control subjects, as was their prevalence of LJM higher. Since the prayer sign was correlated to exactly measured ROMs, we would suggest using the prayer sign as a simple clinical indicator for LJM in diabetic subjects.

A prospective study of predictors for foot ulceration in type 2 diabetes.

One hundred eighty-seven type 2 diabetic patients without a history of foot ulceration were followed for a mean period of 3.6 years to investigate the incidence of foot ulceration in a diabetes cohort and to analyze risk factors for foot ulceration by multivariate means. During the study, 10 subjects developed 18 forefoot ulcerations. In multivariate logistic regression, significant predictors for foot ulceration were an elevated vibration perception threshold (VPT) (relative risk [RR] = 25.4), an increased plantar pressure (RR = 6.3), and daily alcohol intake (RR = 5.1). This is the first prospective study to demonstrate plantar pressure and daily alcohol intake as predictors of foot ulceration among patients without previous ulceration. Further, VPT could be confirmed as the strongest predictor for foot ulceration, and it was clearly demonstrated that the more pronounced severity of complications occurred among subjects with elevated VPT.

Estimation of risk for plantar foot ulceration in diabetic patients with neuropathy.

The main risk factors for plantar forefoot ulcers are loss of protective sensation due to sensory neuropathy and increased mechanical stress on the sole of the foot. The aim of this study was to find a better parameter than the plantar pressure to explain the occurrence of plantar ulcers under the metatarsalheads (MTHs). Twenty diabetic patients (3 Type 1 and 17 Type 2) each with 1 plantar ulcer and 23 Type 2 diabetic patients without plantar ulceration (controls), were investigated. The parameters of plantar pressure, length of contact time and pressure-time integral (PTI) were determined by pedography at defined foot regions. PTI represents the duration of mechanical stress on the foot. Based on the distribution of ulcers, the ratio of stress on the MTHs to that on the big toe was calculated. In diabetic patients with ulcers the difference of PTI between MTHs and hallux was higher at 153% and hence 3.2 times greater than the difference in plantar pressure between MTHs and hallux of 47.3%. In the control group the ratio of difference had a factor of 2 only because the corresponding difference in PTI was 85.1% and the difference in plantar pressure was 43.1%. These results may indicate that increased stress at the MTHs is responsible for the occurrence of planar ulcers compared with other regions of the sole. Diabetic patients with elevated PTI ratio are at risk of developing foot ulcers and therefore have to be provided with orthopaedic shoes to prevent foot ulceration.

[Risk factors for increased plantar pressure in type 2 diabetes]. / Risikofaktoren für einen erhöhten plantaren Druck bei Typ 2 Diabetes.

Diabetic foot ulcers develop at high pressure sites, whereby causal factors for increased plantar pressure are insufficiently investigated. We clinically inspected the feet of 186 Type 2-diabetic patients and measured peripheral neuropathy and plantar pressure during walking. Subjects were assigned into a group with normal (n = 113) and elevated (n = 73) plantar pressure. In patients with elevated plantar pressure body weight was significantly increased (85.4 +/- 12.3 kg vs. 80.7 +/- 13.8), as was plantar pressure increased at the hallux (519 +/- 322 kPa vs. 346 +/- 154), at the metatarsal head I (MTH) I (442 +/- 270 vs. 235 +/- 95) and at the MTH II-V (788 +/- 277 vs. 446 +/- 145). The vibration perception threshold was significantly higher among these patients (21.8 +/- 11.0 Volt vs. 16.7 +/- 9.0), as was the prevalence of hyperkeratosis (69.9% vs. 43.4) and clawed toes (28.8% vs. 15.9). In a multiple regression analysis, hyperkeratosis (Beta = 0.25, p < 0.001) and body weight (Beta = 0.27, p < 0.001) were significant risk factors, but did not describe the whole variation of plantar pressure in the multivariate model. Limited joint mobility (LJM), which was not measured but estimated in the present study, was slightly more prevalent among patients with elevated plantar pressures (46.6 vs. 33.6%). It could be assumed, that LJM, if exactly measured, is a significant risk factor in a multivariate analysis, too.

[Effect of limited joint mobility on plantar pressure in patients with type 1 diabetes mellitus]. / Der Einfluss der Limited joint mobility auf den plantaren Druck bei Patienten mit Diabetes mellitus Typ 1.

Limited joint mobility (LJM) in the foot as well as the relationship of LJM and plantar pressure have not been well examined in patients with Type 1 diabetes mellitus. Pronation of the foot during stance phase is helping to absorb the shock of impact. Pronation of the foot is inevitably connected with abduction and dorsiflexion of the foot. We investigated the relationship of LJM and plantar pressure in 50 patients with Type 1 diabetes mellitus (age 40 +/- 11 years, duration of diabetes 23 +/- 10 years, HbA1c 8.2 +/- 1.1%) and the differences in joint mobility between these patients and 44 nondiabetic controls (age 35 +/- 10 years). Joint mobility was measured with a pocket-goniometer; plantar pressure was measured with a pedography platform during walking about barefoot. Statistical analysis showed a significant correlation between range of motion at the talocrural joint and the plantar pressure under the metatarsalheads 2-5, and at the right metatarsophalangeal joint 1 and the plantar pressure under the MTHs 4-5 respectively in diabetic patients. That means, the smaller the range of motion, the higher the plantar pressure. The range of motion in diabetic patients was smaller at the talocrural and metatarsophalangealjoint 1 than in controls. Increase of plantar pressure can be caused by LJM because it impares the shock absorbing capability of the forefoot.