The diabetic neuropathic foot: a triple crush syndrome--measurement of compartmental pressures of normal and diabetic feet.

The role of chronic swelling in the feet of diabetic patients with severe neuropathy is unclear. It was hypothesized that swelling might raise the compartment pressures of the foot high enough above normal to produce nerve and soft tissue injury, ie, the triple crush syndrome. Four compartment measurements were recorded in 30 feet of 15 normal patients and in 34 feet of 20 patients with severe diabetic neuropathy and normal large vessel arterial blood flow. The lateral compartments produced unreliable results and were discarded from statistical evaluation. The mean medial compartment pressure was 7.8 mm Hg (SD 2.55) in the normal feet and 9.4 mm Hg (SD 4.08) in the diabetic feet. This was not a statistically significant difference. Highly significant differences were recorded in the interosseous and central compartments where the mean pressures were 6.4 mm Hg (SD 2.72) and 5.7 mm Hg (SD 2.89), respectively, in the normal feet and 9.3 mm Hg (SD 4.75) and 8.9 mm Hg (SD 5.0) in the diabetic feet (P < .05 for each group). Furthermore, within the diabetic group, 9 of 9 patients (100%) with clinically swollen feet had at least one compartment pressure measure two standard deviations (12 mm Hg) or greater compared with 5 of 11 (45%) in those without clinical swelling. This difference is significant (P < .01). We could not correlate elevated compartment pressures directly with soft tissue pathology.(ABSTRACT TRUNCATED AT 250 WORDS)