Screening techniques to identify people at high risk for diabetic foot ulceration: a prospective multicenter trial.

OBJECTIVE: Diabetic foot ulceration is a preventable long-term complication of diabetes. A multicenter prospective follow-up study was conducted to determine which risk factors in foot screening have a high association with the development of foot ulceration. RESEARCH DESIGN AND METHODS: A total of 248 patients from 3 large diabetic foot centers were enrolled in a prospective study. Neuropathy symptom score, neuropathy disability score (NDS), vibration perception threshold (VPT), Semmes-Weinstein monofilaments (SWFs), joint mobility, peak plantar foot pressures, and vascular status were evaluated in all patients at the beginning of the study. Patients were followed-up every 6 months for a mean period of 30 months (range 6-40), and all new foot ulcers were recorded. The sensitivity, specificity, and positive predictive value of each risk factor were evaluated. RESULTS: Foot ulcers developed in 95 feet (19%) or 73 patients (29%) during the study. Patients who developed foot ulcers were more frequently men, had diabetes for a longer duration, had nonpalpable pedal pulses, had reduced joint mobility, had a high NDS, had a high VPT, and had an inability to feel a 5.07 SWE NDS alone had the best sensitivity, whereas the combination of the NDS and the inability to feel a 5.07 SWF reached a sensitivity of 99%. On the other hand, the best specificity for a single factor was offered by foot pressures, and the best combination was that of NDS and foot pressures. Univariate logistical regression analysis yielded a statistically significant odds ratio (OR) for sex, race, duration of diabetes, palpable pulses, history of foot ulceration, high NDSs, high VPTs, high SWFs, and high foot pressures. In addition, 94 (99%) of the 95 ulcerated feet had a high NDS and/or SWF which resulted in the highest OR of 26.2 (95% CI 3.6-190). Furthermore, in multivariate logistical regression analysis, the only significant factors were high NDSs, VPTs, SWFs, and foot pressures. CONCLUSIONS: Clinical examination and a 5.07 SWF test are the two most sensitive tests in identifying patients at risk for foot ulceration, especially when the tests are used in conjunction with each other. VPT measurements are also helpful and can be used as an alternative. Finally, foot pressure measurements offer a substantially higher specificity and can be used as a postscreening test in conjunction with providing appropriate footwear.

Evaluation of a collagen-alginate wound dressing in the management of diabetic foot ulcers.

Efficacy and safety of a collagen-alginate topical wound dressing (FIBRACOL Collagen-Alginate Wound Dressing) in the treatment of diabetic foot ulcers was compared with that of regular gauze moistened with normal saline. Seventy-five patients with foot ulcers were assigned randomly in a 2:1 ratio to the collagen-alginate test dressing or the gauze dressing. At the end of the study, the mean percent reduction of the wound area was 80.6% +/- 6% in the collagen-alginate dressing group and 61.1% +/- 26% in the gauze dressing group (p = .4692). Thirty-nine (78%) patients treated with the collagen-alginate dressing achieved > or = 75% wound area reduction, compared with 15 (60%) of gauze-treated patients. Complete healing was achieved in 24 (48%) of the collagen-alginate dressing group and 9 (36%) of the gauze dressing group. Wound size, when averaged over the 8-week period and with the duration of the ulcer taken into account, was reduced significantly in the collagen-alginate dressing group, as compared with the gauze dressing group (df = 1, p = .0049). It is concluded that the collagen-alginate test dressing is as or more effective and safe as the currently used treatment.

Neuropathic ulcerations plantar to the lateral column in patients with Charcot foot deformity: a flexible approach to limb salvage.

Neuroarthropathy of the midfoot may lead to a structural deformity that predisposes the diabetic patient to skin breakdown and ulceration. In some cases, conservative management is not adequate, making surgical intervention necessary. The authors performed a retrospective study to look at those patients who required surgical intervention for a specific pattern of neuroarthropathy. Over a 2 1/2-year period, 32 feet (31 patients) underwent surgical procedures for treatment of nonhealing neuropathic ulcerations beneath the lateral column of Charcot feet. All feet underwent exostectomy with 17 undergoing excision of the ulcer with primary closure, 8 closure via rotational fasciocutaneous flap with transpositional intrinsic muscle flap, and 6 through an incision placed adjacent to the ulcer. One patient whose ulcer was healed at the time of surgery had the incision placed directly over the prominence. Overall, 29 of 32 feet maintained functional limb salvage. This included eight patients who required revisional surgery, either by resection of more bone or creation of a local flap for coverage. Life-table analysis resulted in an 89% overall success rate. The results show that a flexible approach to skin and soft tissue coverage is necessary to heal these patients, provided attention is directed to the underlying bony prominence.

Aerobic exercise capacity remains normal despite impaired endothelial function in the micro- and macrocirculation of physically active IDDM patients.

The aim of the present study was to examine if diabetes in the absence of neuropathy affects the exercising capacity of IDDM patients, and whether regular, intense training has a beneficial effect on endothelial function. Five groups of subjects were studied: 23 healthy control subjects who exercised regularly (age 33 +/- 6 years), 23 nonneuropathic type 1 diabetic patients who exercised regularly (age 33 +/- 6 years, IDDM duration 11 +/- 8 years), 7 neuropathic type 1 diabetic patients who exercised regularly (age 36 +/- 7 years, IDDM duration 22 +/- 8 years), 18 healthy subjects who did not exercise regularly (age 34 +/- 7 years), and 5 nonneuropathic type 1 diabetic patients who did not exercise regularly (age 31 +/- 4 years, IDDM duration 20 +/- 3 years). All groups were matched for age, sex, and body weight. No differences existed in the energy expenditure per week in physical activity among the three exercising groups or between the two nonexercising groups. The maximal oxygen uptake was similar between control and diabetic nonneuropathic exercisers, and among diabetic neuropathic exercisers, control nonexercisers, and diabetic nonexercisers; however, a significant difference existed between the first two and the last three groups (P < 0.0001). A stepwise increase was found in the resting heart rate among the groups, ranging from the lowest in control exercisers to the highest in diabetic nonexercisers, but the maximal heart rate was lower only in diabetic neuropathic exercisers compared with all other groups (P < 0.05). Assessments of endothelial function in both macro- and microcirculation were performed in 12 control exercisers, 10 diabetic nonneuropathic exercisers, 5 diabetic neuropathic exercisers, 17 control nonexercisers, and 4 diabetic nonexercisers. When all diabetic patients were considered as one group and all control subjects as another, the microcirculation endothelial function in the diabetic group was reduced compared with the control subjects (91 +/- 49 vs. 122 +/- 41% flux increase over baseline; P < 0.05). In contrast, no differences existed among the three diabetic groups or between the two control groups. Similarly, in macrocirculation, a reduced response during reactive hyperemia was observed in the diabetic patients compared with control subjects (7.0 +/- 4.5 vs. 11.2 +/- 6.6% diameter increase; P < 0.05), whereas again no difference existed among the three diabetic groups or between the two control groups. These data suggest that diabetes per se does not affect aerobic exercise capacity (VO2max) in physically active individuals, but is reduced in the presence of neuropathy. In addition, regular exercise training involving the lower extremities does not improve the endothelial function in the micro- and macrocirculation of the nonexercised upper extremity in type 1 diabetic patients.

Longitudinal in-shoe foot pressure relief achieved by specially designed footwear in high risk diabetic patients.

Specially designed Thor-Lo footwear has been shown to reduce the in-shoe foot pressures in diabetic patients at risk of foot ulceration when compared to their own footwear. Fifty at high risk patients 32 (64%) males, 17 (34%) type 1 diabetes) have been provided with this foot wear and have been followed up for 6 months. Mean age was 57.6 (range, 34-78) years, duration of diabetes 22.4 (range, 4-50) years, Neuropathy Symptom Score 3.36 +/- 2.96 (mean +/- S.D.), Neuropathy Disability Score 16.8 +/- 6.83, VPT 43.4 +/- 11.8 Volts while 43 (86%) could not feel a 5.07 or smaller Semmes-Weinstein monofilament. Forty-two (84%) patients were re-examined at an interim visit 3 months after baseline, while 37 (74%) completed the study. In-shoe peak forces and pressures were measured using the F-Scan system. No difference was found among the peak force among baseline (95.5 +/- 26 kg), interim (96.5 +/- 33) and final visit (97.7 +/- 25.2, P + NS). There was no difference in peak pressures at the baseline (3.98 +/- 1.42 kg.cm-2), second visit (4.13 +/- 2.30) and the final visit (4.25 +/- 1.51). Nine (18%) patients developed foot problems and one died during the study. We conclude that no changes in foot pressures were found over a period of 6 months of continuous usage of the specially designed footwear in a group of diabetic patients at risk of foot ulceration. Further prospective studies are required to evaluate the impact of specially designed footwear in reducing the rate of foot ulceration.

The impact of reversal of hypoxia by revascularization on the peripheral nerve function of diabetic patients.

Hypoxia is considered to be one of the main aetiopathogenic factors of diabetic neuropathy. We have examined the effects of the reversal of hypoxia, achieved by revascularization, on peripheral nerve function in diabetic patients with or without clinical neuropathy. Fifty-six patients [mean age 62 (range 30-74) years, 44 (79%) males, 15 (27%) with insulin-dependent diabetes of 20 years (range 1-57) duration, and creatinine level 92.8 +/- 30.9 mumol/l (mean +/- SD)] were tested pre-operatively while 30 (54%) were reexamined at least 6 weeks post-operatively. At baseline the leg scheduled for operation showed worse measurements compared to the control leg when tested for Semmes-Weinstein monofilaments, peroneal motor conduction velocity (PMCV) (33.7 +/- 7.18 vs 35.7 +/- 6.09 m.s-1, p < 0.05) and transcutaneous oxygen tension (37.4 +/- 24.6 vs 52.0 +/- 21.5 mm Hg, p < 0.0001) while no differences were found in the vibration perception threshold and leg temperature. When baseline and post-operative measurements were later compared in the operated leg, no differences were noticed in the vibration perception threshold, PMCV and Semmes-Weinstein monofilaments but the transcutaneous oxygen tension increased significantly (32.7 +/- 27.1 vs 64.6 +/- 14.5 mm Hg, p < 0.001). No differences were noticed in any of the above parameters in the contralateral leg. No correlations were found between changes in transcutaneous oxygen tension and PMCV values measured at baseline and at the follow-up visit in either leg. Similar results were found when patients were stratified according to severity of neuropathy, ischaemia and the level of the bypass. We conclude that although there is greater impairment of nerve function in the more ischaemic leg, reversal of hypoxia does not result in any significant improvement of the nerve function measurements.

Differences in joint mobility and foot pressures between black and white diabetic patients.

Limited joint mobility is common in diabetes and is related to high foot pressures and foot ulceration. We have examined the differences in joint mobility and foot pressures in four groups matched for age, sex, and duration of diabetes: 31 white diabetic, 33 white non-diabetic, 24 black diabetic, and 22 non-diabetic black subjects. Joint mobility was assessed using a goniometer at the fifth metacarpal, first metatarsal, and subtalar joints. In-shoe and without shoes foot pressures were measured using an F-Scan system. Neuropathy was evaluated using clinical symptoms (Neuropathy Symptom Score), signs (Neuropathy Disability Score), and Vibration Perception Threshold. There was no difference between white and black diabetic patients in Neuropathy Symptom Score, Neuropathy Disability Score, and Vibration Perception Threshold. Subtalar joint mobility was significantly reduced in white diabetic patients (22 +/- 7 degrees) compared to white controls (26 +/- 4 degrees, black diabetic patients (25 +/- 5 degrees), and black controls (29 +/- 7 degrees), and increased in black controls compared to white controls and black diabetic patients (level of statistical significance p < 0.05). Without shoes foot pressures were higher in white diabetic patients (8.31 +/- 400 kg cm-2) compared to white controls (6.81 +/- 2.31 kg cma2), black diabetic patients (6.2 +/- 2.53 kg cm-2) and black controls (5.00 +/- 1.24 kg cm-2) and lower in black controls compared to white and black diabetic patients (p < 0.05 in all cases). We conclude that racial differences exist in joint mobility and foot pressures between black and white subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

Variability in function measurements of three sensory foot nerves in neuropathic diabetic patients.

We have examined the variability in function measurements of three sensory foot nerves in neuropathic diabetic patients and have compared them to measurements from healthy non-diabetic subjects. Sixty-six healthy, non-diabetic subjects (30 (45%) males, mean age 56 years (range, 21-84 years)) and 61 age and sex matched diabetic patients (33 (54%) males, mean age 55 years (range, 34-78 years) Type 1 diabetes mellitus (DM), mean duration of DM 24 years (range, 2-48 years)) were tested. Current perception threshold (CPT) at 250 Hz was employed to test the sensory function of three nerves: superficial peroneal, sural and posterior tibial. The vibration perception threshold, (VPT) and the cutaneous perception threshold (CCPT) were also assessed at the great toe. According to the results of the neuropathy disability score (NDS), mild neuropathy was present in 8 (13%) patients, moderate in 33 (54%) and severe in 20 (33%). In both groups the CPT of the posterior tibial nerve was higher than the other two nerves (P < 0.0001) while no difference was found between the superficial peroneal and sural nerves (P = NS). CPT was different between the two feet at the superficial peroneal nerve in 39 (64%) diabetic patients and 34 (52%) controls (P = NS), at the sural nerve in 40 (65%) and 45 (68%) (P = NS), and at the posterior tibial in 36 (59%) and 33 (50%), respectively (P = NS). VPT was different by more than 10% at the great toes in 26 (43%) diabetic subjects and CCPT in 21 (34%). We conclude that although there is variation in sensory nerve function tests in diabetic patients this is similar to that noticed in healthy subjects. The great variability of all quantitative sensory testing indicates that more than one site should be tested.

The role of foot surgery in patients with diabetes.

In conclusion, surgery on the diabetic foot should be looked upon as a required addition to quality conservative care. The success that can be gained from proper performance of these procedures can be rewarding and often improves the ability to salvage limbs that may have otherwise been lost because of ulceration, infection, instability, or pain.

Preventing loss of the great toe with the hallux interphalangeal joint arthroplasty.

Chronic ulcerations of the hallux may result in amputation if infection becomes uncontrolled. Salvage of the hallux often requires surgical intervention when conservative measures fail. Many authors have described various procedures to prevent recurrent ulceration and the potential for loss of the great toe. The authors have reviewed their experience with the hallux interphalangeal joint arthroplasty for chronic neuropathic ulcers of the great toe. Between August 1988 and July 1991, the authors performed 46 hallux interphalangeal joint arthroplasties on 40 patients (22 males, 18 females). Of the 40 original patients, one patient was lost to follow-up in the immediate postoperative period, leaving 45 procedures on 39 patients. Thirty-six feet were noted to heal both the procedure and ulceration uneventfully (80%). There were five minor complications (11%). Four cases were deemed failures (9%). Overall, 41 feet (91%) healed and had no evidence of recurrence in the follow-up period. Follow-up was an average of 23.6 months (range 4-44 months). The hallux interphalangeal joint arthroplasty has been a valuable procedure for chronic ulcerations of the hallux. By allowing these ulcers to heal, loss of the great toe has been avoided. Function and structure of the foot has been maintained.

In-shoe foot pressure measurements in diabetic patients with at-risk feet and in healthy subjects.

OBJECTIVE: To measure in-shoe foot pressures in diabetic patients and healthy subjects and compare them with the foot pressures when they walked without their shoes. RESEARCH DESIGN AND METHODS: Forty-four diabetic patients at risk of foot ulceration and 65 healthy subjects were matched for age, sex, race, and weight. Neuropathy was evaluated clinically, and the F-Scan program was used to measure the foot pressures. Foot pressures were measured with the sensors placed in the shoes (S measurements), between the foot and the sock with shoes (H measurements) or with their socks alone (B measurements). RESULTS: In the control group, significant differences were found between S (4.77 +/- 1.87 kg/cm2) and H measurements (5.12 +/- 1.87 kg/cm2, P < 0.001), between S and B (7.23 +/- 2.95 kg/cm2, P < 0.0001), and between H and B (P < 0.0001). In the diabetic group, no difference was found between S and H measurements (5.28 +/- 2.22 vs. 5.27 +/- 2.39 kg/cm2, NS). In contrast, the B pressure was significantly higher when compared with both (8.77 +/- 4.67 kg/cm2, P < 0.02). When compared with the control group, the S and H pressures did not differ significantly, but the B pressure in the diabetic group was significantly higher (P < 0.02). The peak S pressure was above the normal limit in 24 (27%) diabetic and 21 (16%) control feet (P < 0.05), the H pressure in 17 (19%) diabetic feet and 22 (17%) control feet (NS), and the B pressure in 24 (27%) diabetic and 21 (16%) control feet (P < 0.05). CONCLUSIONS: In-shoe foot pressure measurements are significantly lower than the ones measured when walking with the socks only in both diabetic patients and healthy subjects. The shoes of diabetic patients provided a higher pressure reduction than did those of the control group, but the number of feet with abnormally high pressures did not change. The F-Scan system may be particularly helpful in designing footwear suitable for diabetic patients with at-risk feet.

Maximizing foot salvage by a combined approach to foot ischemia and neuropathic ulceration in patients with diabetes. A 5-year experience.

OBJECTIVE: The combination of peripheral neuropathy and arterial insufficiency in patients with diabetes frequently results in chronic non-healing foot ulcers. These patients often have a protracted course that commonly ends in limb amputation. RESEARCH DESIGN AND METHODS: Since 1987, 39 diabetic patients presented with 42 neuropathic ulcerations beneath the lesser metatarsal heads, complicated by severe arterial insufficiency. A variety of vascular reconstructions were performed to improve circulation to the foot. After successful vascular reconstruction, 14 patients with deep ulcers underwent resection of the involved bone or joint through a plantar elliptical incision with excision of the ulcer and primary closure (33%). Five patients required a simultaneous panmetatarsal head resection (12%). For fifteen superficial ulcers, metatarsal osteotomy through a dorsal approach was performed (36%). Eight patients underwent a fifth metatarsal head resection through a dorsal approach (19%). RESULTS: In follow-up of 2-64 months (mean 21.2 months), 35 extremities with patent bypass grafts achieved and maintained primary healing of their local foot procedure (83%). Two feet required subsequent revision but ultimately healed (5%). Three feet (7%) developed a new plantar ulceration adjacent to the original one. In two extremities, the foot remained healed in spite of thrombosis of their grafts (5%). One patient with a thrombosed graft required a below-knee amputation. One patient died before the foot healed with a patent bypass graft. Overall, 40 of 42 extremities (95%) ultimately healed over the course of the follow-up period. CONCLUSIONS: We conclude that complex neuropathic ulcers in diabetic patients can be successfully treated by an aggressive surgical approach that removes infected bone and ulcers and corrects underlying structural abnormalities provided arterial insufficiency is corrected first.

Applications and use of in-shoe orthoses in the conservative management of Charcot foot deformity.

Charcot joint arthropathy is one of the more challenging entities encountered by the podiatric physician. The primary goal of treatment is to preserve skin integrity. A secondary goal is to provide a stable extremity for ambulation. The ultimate goal is to improve the quality of life for these individuals. The ability to accomplish these goals by conservative means requires a knowledge of biomechanics as well as orthoses and shoe gear. Perseverance, compassion, and a little creativity often are helpful as well.

Panmetatarsal head resection. A viable alternative to the transmetatarsal amputation.

While the transmetatarsal amputation has resulted in the salvage of numerous diabetic limbs, it remains an ablative procedure with both short- and long-term complications. The authors reviewed their experience with the panmetatarsal head resection as an alternative to the transmetatarsal amputation. A retrospective review was performed of all patients having undergone this procedure between May 1986 and November 1991. Thirty-seven procedures were performed; of these, 34 were evaluated. The average follow-up period was 20.9 months. Thirty-two feet showed primary healing while one showed delayed healing. One patient had local recurrence of the original ulceration. Primary healing was 94% while overall success was 97%. No patient required amputation of any kind. The authors conclude that the panmetatarsal head resection is a viable alternative to the transmetatarsal amputation in properly selected patients because it avoids many of the structural and biomechanical pitfalls of the transmetatarsal amputation.

A biomechanical model for the transmetatarsal amputation.

The transmetatarsal amputation has been performed for over 40 years as a limb salvage procedure, in diabetic patients with nonhealing ulcerations or nonreconstructible ischemia. It is generally believed that the transmetatarsal amputation provides a better walking extremity than a more proximal amputation and is more energy efficient. A review of the literature reveals little regarding the biomechanics of the "short foot." The authors will review the functions of the myofascial structures in both the normal foot and the transmetatarsal amputation and discuss the influence of mechanics on transmetatarsal amputation lesions.

Tendo Achillis procedures for chronic ulcerations in diabetic patients with transmetatarsal amputations.

Recurrent ulceration following transmetatarsal amputation commonly results from hypertrophic bone formation or equinus deformity. In the current study, 31 diabetic patients underwent 33 Achilles tendon procedures for recurrent ulcerations at the distal stump of their transmetatarsal amputation. Primary healing was achieved in 21 procedures (64%) and secondary healing in 9 procedures (27%) for an overall healing rate of 91%. Two procedures failed to resolve the original ulceration (6%). The average follow-up examination was 27 months. The authors conclude that Achilles tendon procedures are an effective means of managing ulcerations in transmetatarsal amputation feet exhibiting an equinus deformity.

Sesamoidectomy for the treatment of chronic neuropathic ulcerations.

Neuropathic ulcerations in diabetic patients are frequent causes of hospitalizations and morbidity. The plantar aspect of the first metatarsophalangeal joint is a common location for these ulcerations, because of the significant weightbearing forces generated through this joint and the presence of sensory and motor neuropathy. The authors describe 24 cases in which excision of the tibial sesamoid, fibular sesamoid, or both, was performed to resolve these lesions.

Charcot's disease in diabetic patients. Correct diagnosis can prevent progressive deformity.

Although Charcot's disease and its association with diabetes have been described many times in the literature, it is still often misdiagnosed and incorrectly treated as osteomyelitis, arthritis, or gout. The best safeguard is a high index of suspicion. A warm, swollen foot in a diabetic patient with long-standing neuropathy without local or systemic signs of infection must be considered Charcot's disease until proven otherwise. The principal treatment is total abstinence from putting weight on the foot until warmth, swelling, and redness subside. Protective weight-bearing methods may then be slowly instituted.

Review of metatarsal osteotomies for the treatment of neuropathic ulcerations.

The records of 52 patients who underwent metatarsal osteotomies for the treatment of chronic neuropathic ulcerations between the years 1983 and 1985 were analyzed in a retrospective study. Long-term follow-up information was available for all but three patients. All patients were conservatively managed preoperatively and postoperatively with shoes, accommodative orthoses, and local care. A limb salvage rate of 94%, 46 of 49 patients, was achieved in this study. Although 13 patients developed transfer ulcerations, all but one were managed either with conservative care or a lesser podiatric procedure, and all remain healed to date.