Limited joint mobility in the hand is a common manifestation of diabetes with the reported prevalence in insulin-dependent diabetes varying between 8 and 43%. Sixty-two subjects were studied in three groups (controls, diabetic patients without foot problems, and diabetic patients with neuropathic ulceration) to determine whether similar changes occur in the joints of the foot and to examine any possible relationship with neuropathic ulceration. There was a significant impairment of mobility in the range of motion of the sub-talar joint in diabetic patients with ulcers when compared with controls (p = 0.0001) or with the other diabetic patients (p = 0.004). There was a significant correlation between sub-talar range of motion and mobility in other joints of the foot such as at the hallux (r = 0.59, p less than 0.001), or with mobility of the 5th finger (r = 0.41, p less than 0.01). There was also a significant association between the clinical presence of limited joint mobility in the hand, Dupuytren's contracture, and mobility of the sub-talar joint (p less than 0.05). Furthermore, impairment of mobility of the sub-talar joint was greatest on the affected side in those diabetic patients with neuropathic ulceration (p = 0.029). We conclude that the syndrome of limited joint mobility also affects the joints of the feet of diabetic patients and may predispose to ulceration in susceptible neuropathic feet.

Somatogenic (i.e. GH) receptors have been studied on liver microsomal membranes from male and female rats. Tracer bovine GH was displaced from its binding sites by GHs of various species, but was displaced only weakly by PRLs. Specific bovine GH binding was 3.5-fold higher to female rat liver membranes than to membranes from males. Streptozotocin-induced diabetes significantly reduced binding, by 80% in females and 50% in males, while insulin therapy to normalize weight gain reversed the decrease in binding. Competitive binding curves were consistent with two independent classes of binding site: low affinity sites with K equal to 0.5 nm-1 in both sexes, and high affinity sites with K equal to 12.1 nm-1 in males and 21.4 nm-1 in females (P less than 0.001). The addition of excess ovine PRL caused a substantial loss of high affinity binding with little loss in the low affinity region, suggesting a weak somatogenic role for ovine PRL. In diabetic animals, low affinity sites were unchanged from normal, while high affinity sites were decreased in number, with no change in affinity, and restored on insulin therapy. Serum immunoreactive rat GH levels were the same in normal and diabetic, male and female animals. These studies suggest that the apparent hepatic resistance to GH seen in diabetes when liver somatomedin release is low despite normal serum GH might be explained by the loss of GH receptors in this condition.

The Diabetes Knowledge Assessment (DKN) scales were developed to meet a specific need for rapid and reliable knowledge assessment in diabetic patients. Item format and item selection from an initial pool of 89 items were determined by pilot-testing over 300 diabetic subjects. Reliability analysis of the resulting 40 multiple-choice items, with a further sample of 56 subjects, gave a Cronbach's alpha coefficient of 0.92. Parallel forms DKNA, DKNB, and DKNC, each of 15 items selected from the parent set, had alpha coefficients above 0.82 and correlated 0.90 with each other. A full clinical trial, using DKNA, DKNB, and DKNC in randomized order of presentation, was conducted with 219 subjects attending a 2-day diabetes education program. Overall DKN scores improved from 7.6 (51%) to 11.3 (75%). Analysis of variance confirmed that DKNA, DKNB, and DKNC were equivalent forms at pretest. Mean posttest scores on DKNB were lower than the other scales (P less than 0.001), but variances were equivalent for all three. A specific local change in the education program format was found to account for this discrepancy in the DKNB posttest mean. In situations where comprehensive assessment of diabetes knowledge would be time-consuming and unnecessary, these results indicate that rapid and reliable assessment is possible with a scale of only 15 validated items. The development of parallel forms of the scale extends the range of retesting possibilities for diagnosis and research.