Diet and exercise interventions reduce intrahepatic fat content and improve insulin sensitivity in obese older adults

Both obesity and aging increase intrahepatic fat (IHF) content, which leads to nonalcoholic fatty liver disease (NAFLD) and metabolic abnormalities such as insulin resistance. We evaluated the effects of diet and diet in conjunction with exercise on IHF content and associated metabolic abnormalities in obese older adults. Eighteen obese (BMI >or=30 kg/m(2)) older (>or=65 years old) adults completed a 6-month clinical trial. Participants were randomized to diet (D group; n = 9) or diet + exercise (D+E group; n = 9). Primary outcome was IHF quantified by magnetic resonance spectroscopy (MRS). Secondary outcomes included insulin sensitivity (assessed by oral glucose tolerance), body composition (assessed by dual-energy X-ray absorptiometry), physical function (VO(2 peak) and strength), glucose, lipids, and blood pressure (BP). Body weight (D: -9 +/- 1%, D+E: -10 +/- 2%, both P < 0.05) and fat mass (D: -13 +/- 3%, D+E -16 +/- 3%, both P < 0.05) decreased in both groups but there was no difference between groups. IHF decreased to a similar extent in both groups (D: -46 +/- 11%, D+E: -45 +/- 8%, both P < 0.05), which was accompanied by comparable improvements in insulin sensitivity (D: 66 +/- 25%, D+E: 68 +/- 28%, both P < 0.05). The relative decreases in IHF correlated directly with relative increases in insulin sensitivity index (ISI) (r = -0.52; P < 0.05). Improvements in VO(2 peak), strength, plasma triglyceride (TG), and low-density lipoprotein-cholesterol concentration, and diastolic BP occurred in the D+E group (all P < 0.05) but not in the D group. Diet with or without exercise results in significant decreases in IHF content accompanied by considerable improvements in insulin sensitivity in obese older adults. The addition of exercise to diet therapy improves physical function and other obesity- and aging-related metabolic abnormalities.

Effect of weight loss and exercise therapy on bone metabolism and mass in obese older adults: a one-year randomized controlled trial

BACKGROUND

Although weight loss and exercise ameliorates frailty and improves cardiac risk factors in obese older adults, the long-term effect of lifestyle intervention on bone metabolism and mass is unknown.

OBJECTIVE

The objective was to evaluate the effects of diet-induced weight loss in conjunction with exercise on bone metabolism and mass in obese older adults.

DESIGN AND SETTING

We conducted a one-year randomized, controlled clinical trial in a university-based research center.

PARTICIPANTS

Twenty-seven frail, obese (body mass index = 39 +/- 5 kg/m(2)), older (age 70 +/- 5 yr) adults participated in the study.

INTERVENTION

Participants were randomly assigned to diet and exercise (treatment group; n = 17) or no therapy (control group; n = 10).

OUTCOME MEASURES

Body weight decreased in the treatment group but not in the control group (-10 +/- 2 vs. +1 +/- 1%, P < 0.001). Compared with the control group, the treatment group had greater changes in bone mass, bone markers, and hormones, including 1) bone mineral density (BMD) in total hip (0.1 +/- 2.1 vs. -2.4 +/- 2.5%), trochanter (0.2 +/- 3.3 vs. -3.3 +/- 3.1%), and intertrochanter (0.3 +/- 2.7 vs. -2.7 +/- .3.0%); 2) C-terminal telopeptide (12 +/- 35 vs. 101 +/- 79%) and osteocalcin (-5 +/- 15 vs. 66 +/- 61%); and 3) leptin (2 +/- 12 vs. -30 +/- 25%) and estradiol (0.1 +/- 14% vs. -14 +/- 21%) (all P < 0.05). Changes in weight (r = 0.55), bone markers (r = -0.54), and leptin (r = 0.61) correlated with changes in hip BMD (all P < 0.05).

CONCLUSION

Weight loss, even when combined with exercise, decreases hip BMD in obese older adults. It is not known whether the beneficial effects of weight loss and exercise on physical function lower the overall risk of falls and fractures, despite the decline in hip BMD.

Mid foot kinetics characterize structural polymorphism in diabetic foot disease

BACKGROUND

Diabetic foot disease is characterized by progressive foot deformities that lead to amputation and disabling morbidity. The purpose is to investigate the classification of two distinct phenotypes of mid foot structural polymorphism in individuals using plantar kinetic and pressure distribution and tarsal bone density assessments.

METHODS

Twenty-two individuals (26 ft) with diabetes mellitus, peripheral neuropathy and at least one mid foot deformity were compared to 29 age-, gender- and race-matched healthy controls (58 ft). Eleven subjects with diabetes mellitus and peripheral neuropathy (11 ft) had lateral deformity; 11 subjects (15 ft) had medial deformity. Each subject had calcaneal bone mineral density and plantar force and pressure assessments walking barefoot over an EMED-ST P-2 platform.

FINDINGS

Control subjects had lower mid foot vertical forces and pressures despite significantly higher preferred walking speed. In subjects with diabetes and neuropathy, maximum vertical force was 6-fold greater, force-time integral 9.5-fold greater, peak pressure 6.7-fold higher, pressure-time integral was 9.7-fold greater, contact area 2-fold greater and contact time 1.9-fold higher than controls. Pressure values were larger in involved vs uninvolved (P0.05). During stance in the mid foot, subjects with medial column phenotype showed greater pressure in the medial mask; subjects with lateral column phenotype had greater pressures in the lateral mask (P<0.05). Calcaneal bone density was lower for the deformity foot vs the non-deformity foot; bone mineral density was lower in medial column phenotype vs lateral column phenotype (P=0.02).

INTERPRETATION

Diabetic foot disease can be classified as stereotypical, structurally-distinct phenotypes of deformities of the medial and lateral columns of the mid foot. Assessments of pedal bone density and plantar mid foot force and pressure during barefoot walking can characterize the structural polymorphic phenotypes and may assist the foot care specialist in clinical decision making.

Training-induced strength and functional adaptations after hip fracture

BACKGROUND AND PURPOSE

At 3 months after hip fracture, most people are discharged from physical therapy despite residual muscle weakness and overall decreased functional capabilities. The purposes of this study were: (1) to determine, in frail elderly adults after hip fracture and repair, whether a supervised 6-month exercise program would result in strength gains in the fractured limb equivalent to the level of strength in the nonfractured limb; (2) to determine whether the principle of specificity of training would apply to this population of adults; and (3) to determine the relationship between progressive resistance exercise training (PRT) intensity and changes in measures of strength and physical function.

SUBJECTS

The study participants were 31 older adults (9 men and 22 women; age [X+/-SD], 79+/-6 years) who had surgical repair of a hip fracture that was completed less than 16 weeks before study enrollment and who completed at least 30 sessions of a supervised exercise intervention.

METHODS

Participants completed 3 months of light resistance and flexibility exercises followed by 3 months of PRT. Tests of strength and function were completed at baseline, before PRT, and after PRT.

RESULTS

After PRT, the subjects increased knee extension and leg press 1-repetition maximum by 72%+/-56% and 37%+/-30%, respectively. After 3 and 6 months of training, lower-extremity peak torques all increased. Specificity of training appeared to apply only to the nonfractured limb after PRT. Strong correlations were observed between training intensity and lower-extremity strength gains as well as improvements in measures of physical function.

DISCUSSION AND CONCLUSION

Frail elderly adults after hip fracture can benefit by extending their rehabilitation in a supervised exercise setting, working at high intensities in order to optimize gains in strength and physical function.

Effect of lifestyle intervention on metabolic coronary heart disease risk factors in obese older adults

BACKGROUND

Coronary heart disease (CHD) risk factors increase with age and body mass index (BMI; in kg/m2). However, whether lifestyle intervention ameliorates metabolic CHD risk factors in obese older adults is unknown.

OBJECTIVE

The objective was to determine whether lifestyle intervention improves metabolic CHD risk factors in obese older adults.

DESIGN

A 6-mo outpatient randomized controlled trial was conducted in obese (BMI >or= 30) older (>or=65 y) adults randomly assigned to diet and exercise therapy (treatment group; n = 17) or no therapy (control group; n = 10). The main outcomes were CHD risk factors.

RESULTS

Body weight decreased by 8.4% (8.2 kg) in the treatment group; weight did not change significantly (0.7 kg) in the control group (P < 0.001 between groups). Changes between the control and treatment groups, respectively, in waist circumference (1 and -10 cm), plasma glucose (4 and -4 mg/dL), serum triacylglycerols (0 and -45 mg/dL), and systolic (-2 and -10 mm Hg) and diastolic (0 and -8 mm Hg) blood pressure were different (P < 0.05 for all). The number of subjects with the metabolic syndrome decreased by 59% in the treatment group but did not change significantly in the control group (P < 0.05). Serum free fatty acids increased by 10 micromol/L in the control group and decreased by 99 micromol/L in the treatment group (P < 0.05). Changes between the control and treatment groups, respectively, in C-reactive protein (0.8 and -2.5 mg/L) and interleukin 6 (1.6 and -2.4 pg/mL) were different (P < 0.05 for both).

CONCLUSIONS

Lifestyle intervention decreases multiple metabolic CHD risk factors simultaneously in obese older adults.

Effect of weight loss and exercise on frailty in obese older adults

BACKGROUND

Obesity exacerbates the age-related decline in physical function and causes frailty in older persons. However, appropriate treatment for obese older persons is unknown. We evaluated the effects of weight loss and exercise therapy on physical function and body composition in obese older persons.

METHODS

We screened 40 obese older volunteers and eventually randomized 27 frail obese older volunteers to treatment or control groups. Treatment consisted of 6 months of weekly behavioral therapy for weight loss in conjunction with exercise training 3 times per week. Physical function was evaluated with measurements of frailty (Physical Performance Test, peak oxygen consumption, and Functional Status Questionnaire); strength, gait, and balance tests; body composition with dual-energy x-ray absorptiometry; and quality of life using the Medical Outcomes Survey 36-Item Short-Form Health Survey. Results are reported as mean +/- SD.

RESULTS

Two subjects in the treatment group did not comply with the intervention, and 1 subject in the control group withdrew. Analyses included all 27 subjects originally randomized to the treatment and control groups. The treatment group lost 8.4% +/- 5.6% of body weight, whereas weight did not change in the control group (+0.5% +/- 2.8%; P<.001). Compared with the control group, fat mass decreased (-6.6 +/- 3.4 vs +1.7 +/- 4.1 kg; P<.001), without a change in fat-free mass (-1.2 +/- 2.1 vs -1.0 +/- 3.5 kg; P = .75) in the treatment group. The Physical Performance Test score (2.6 +/- 2.5 vs 0.1 +/- 1.0; P = .001), peak oxygen consumption (1.7 +/- 1.6 vs 0.3 +/- 1.1 mL/min per kilogram; P = .02), and Functional Status Questionnaire score (2.9 +/- 3.7 vs -0.2 +/- 3.9; P = .02) improved in treated subjects compared with control subjects. Treatment also improved strength, walking speed, obstacle course, 1-leg limb stance time, and health survey physical subscale scores (all P<.05).

CONCLUSION

These findings suggest that weight loss and exercise can ameliorate frailty in obese older adults. Trial Registration clinicaltrials.gov Identifier: NCT00146133.

Effects of progressive resistance training on body composition in frail older adults: results of a randomized, controlled trial

BACKGROUND

Progressive resistance exercise training (PRT) has been shown to increase muscle strength and fat-free mass (FFM) in elderly persons. Limited information is available regarding the effects of PRT on lean and fat mass in frail elderly persons.

METHODS

Ninety-one community-dwelling sedentary men and women, 78 years and older with physical frailty (defined using standardized objective criteria) were enrolled in a 9-month trial of exercise training (ET). Physical frailty was defined as having 2 of the 3 following criteria: modified Physical Performance Test score between 18 and 32, peak aerobic power between 10 and 18 ml/kg/min, or self-report of difficulty or assistance with two instrumental activities of daily living or one basic activity of daily living. Participants were randomly assigned to either a control (CTL) group that performed a low intensity home exercise program or a supervised ET group that performed 3 months of low intensity exercise and 3 months of PRT.

RESULTS

After completion of PRT, ET participants had greater improvements than did CTL participants in maximal voluntary force production for knee extension (mean Delta +5.3 +/- 13 ft/lb vs +1.1 +/- 11 ft/lb, p =.05), measured using isokinetic dynamometry. Total body FFM (measured using dual energy x-ray absorptiometry) increased in the ET group, but not in the CTL group (mean Delta +0.84 +/- 1.4 kg vs +0.01 +/- 1.5 kg, p =.005). Total, trunk, intra-abdominal, and subcutaneous fat mass (measured using dual energy x-ray absorptiometry and (1)H-magnetic resonance imaging) did not change in response to PRT.

CONCLUSIONS

Three months of supervised PRT induced improvements in maximal voluntary thigh muscle strength and whole body FFM in frail, community-dwelling elderly women and men. This supervised exercise program may not be sufficient to reduce whole-body or intra-abdominal fat area in this population.

Relationship between changes in activity and plantar ulcer recurrence in a patient with diabetes mellitus

BACKGROUND AND PURPOSE

Although pressure-reducing interventions have been effective in the healing of neuropathic foot ulcers, these ulcers frequently recur in people with diabetes mellitus (DM). This case report illustrates how sudden changes in weight-bearing activity may have affected ulcer recurrence in a patient with DM and how the physical stress theory (PST) relates to ulcer recurrence for this patient.

CASE DESCRIPTION

The patient was a 66-year-old man with a history of DM, peripheral neuropathy, and recurrent plantar ulcers. His plantar ulcer healed after total contact casting.

OUTCOME

Despite relatively low peak plantar pressure (9.3 N/cm(2)), the patient's ulcer recurred within 4 weeks of healing. Plantar pressure assessment and activity monitoring suggested that a rapid and sudden increase in weight-bearing activity (steps per day) contributed to cumulative plantar tissue stress that was 3.3 times higher on the day of ulcer recurrence than his average value. Although his cumulative plantar stress was high compared with his usual value, the cumulative value was similar to the amount of daily stress of individuals without a history of recurrent ulcers.

DISCUSSION

Within the context of the PST, rapid change in activity level may have an effect on cumulative stress and the risk of ulcer recurrence.

Bone mineral density during total contact cast immobilization for a patient with neuropathic (Charcot) arthropathy

BACKGROUND AND PURPOSE

Diabetes mellitus (DM)-related neuropathic arthropathy of the foot is a destructive bone and joint process. The effect of cast immobilization and non-weight bearing on bone loss has not been well studied. The purpose of this case report is to describe the changes in bone mineral density (BMD) of the calcaneus in the feet of a patient with acute neuropathic arthropathy during total contact cast immobilization.

CASE DESCRIPTION

The patient was a 34-year-old woman with type 1 DM, renal failure requiring dialysis, and a 7-week duration of neuropathic arthropathy of the midfoot. Intervention included total contact casting and minimal to no weight bearing for 10 weeks, with transition to therapeutic footwear. Ultrasound-derived estimates of BMD were taken of both involved and uninvolved calcanei.

OUTCOME

Bone mineral density decreased for the involved foot (from 0.25 g/cm(2) to 0.20 g/cm(2)) and increased for the uninvolved foot (from 0.27 g/cm(2) to 0.31 g/cm(2)) during casting.

DISCUSSION

The low initial BMD and further loss during casting suggest the need for transitional bracing and a well-monitored return to full activity to minimize the risk of recurrence and progression of foot deformity.

Persistent pain in frail older adults after hip fracture repair

OBJECTIVES

To identify factors associated with persistent hip pain in elderly hip fracture patients with physical frailty.

DESIGN

Cohort study.

SETTING

Community-based study conducted at academic medical center.

PARTICIPANTS

Eighty-eight men and women (mean age+/-standard deviation 80+/-7 years) with a recent hip fracture (mean 14.5+/-4.8 weeks after hip fracture repair) and physical frailty, defined as a modified Physical Performance Test Score between 12 and 28, enrolled in an exercise intervention trial.

MEASUREMENTS

Dependent variable was self-report of moderate to severe regional hip pain in the week preceding the baseline interview. Independent variables were self-reported demographic information, health characteristics, and activity of daily living (ADL) function; Yesavage Mood Score (YMS); 36-item Short Form percentile scores; and objective measurements of lower extremity strength, range of motion, balance, and gait.

RESULTS

Forty-two percent of the sample reported moderate or severe hip pain at the baseline assessment. Moderate/severe pain was related to difficulty with ADL performance and multiple measures of quality of life. Variables independently associated with moderate/severe hip pain were frequency of pain medication use (adjusted odds ratio (AOR)=5.75, 95% confidence interval (CI)=2.23-14.82, P=.003), YMS score (AOR=2.69, 95% CI=1.18-6.12, P=.02), and knee extension at 60 degrees /s in the fractured limb (AOR=0.96, 95% CI=0.92-1.0, P=.05, model coefficient of determination=0.34).

CONCLUSION

Persistent hip pain is a frequent symptom in frail elderly community-dwelling hip fracture patients. Pain medication use, symptoms of depression, and skeletal muscle weakness of the fractured leg are independent correlates of moderate to severe hip pain in this patient population. Clinicians should assess for, and address, persistent pain in this patient population.

Effect of Achilles tendon lengthening on ankle muscle performance in people with diabetes mellitus and a neuropathic plantar ulcer

BACKGROUND AND PURPOSE

The effect of a tendo-Achilles lengthening (TAL) procedure on ankle muscle performance has not been clearly established. The purpose of this study was to compare the effects of TAL and total-contact casting (TCC) with TCC alone on ankle muscle performance in subjects with diabetes mellitus (DM) and a neuropathic plantar ulcer.

SUBJECTS

Subjects were randomly assigned to either a TAL group (3 female and 12 male subjects) or a TCC group (4 female and 10 male subjects).

METHODS

Muscle performance measurements were obtained using an isokinetic dynamometer.

RESULTS

Concentric plantar-flexor peak torque decreased 31% after TAL but returned to the baseline level after 8 months. Dorsiflexor peak torque did not change in either group. Plantar-flexor passive torque at 0 degrees of dorsiflexion decreased after TAL but increased to 60% of the baseline level after 8 months. Maximal dorsiflexion angle increased 11 degrees after TAL and remained increased at 8 months.

DISCUSSION AND CONCLUSION

The TAL resulted in an increase in ankle dorsiflexion range of motion and a temporary reduction in concentric plantar-flexor peak torque and passive torque at 0 degrees of dorsiflexion. If TAL is being considered for people with DM and a neuropathic forefoot ulcer, the initial compromise in plantar-flexor muscle performance should be addressed.

Physical frailty and body composition in obese elderly men and women

OBJECTIVE

To evaluate the prevalence of frailty and interrelationships among body composition, physical function, and quality of life in community-dwelling obese elderly (OE) persons.

RESEARCH METHODS AND PROCEDURES

Fifty-two OE, 52 nonobese frail, and 52 nonobese nonfrail subjects, matched for age and sex, were studied. Subjective and objective measures of functional status were evaluated by using the physical performance test, exercise stress test, lower extremity (LE) strength, gait speed, static and dynamic balance, functional status questionnaires, and health-related quality-of-life questionnaire (Medical Outcomes Short Form). Body composition was evaluated by using DXA, and muscle quality was evaluated by determining the ratio of LE strength to LE lean mass.

RESULTS

Among OE subjects, 96% met our standard criteria for mild to moderate frailty. Compared with the nonobese nonfrail group, the OE and nonobese frail groups had lower and similar scores in physical performance test, peak aerobic power, and functional status questionnaire, and exhibited similar impairments in strength, walking speed, balance, and health-related quality of life. Although absolute fat-free mass (FFM) was greater, the percentage body weight as FFM and muscle quality was lower in the OE group than in the other two groups.

DISCUSSION

Physical frailty, which predisposes to loss of independence, is common in community-living OE men and women. Physical frailty in OE subjects was associated with low percentage FFM, poor muscle quality, and decreased quality of life. These findings suggest that weight loss therapy may be particularly important in OE persons to improve physical function, in addition to improving the medical complications associated with obesity.

Effects of extended outpatient rehabilitation after hip fracture: a randomized controlled trial

CONTEXT

Hip fractures are common in the elderly, and despite standard rehabilitation, many patients fail to regain their prefracture ambulatory or functional status.

OBJECTIVE

To determine whether extended outpatient rehabilitation that includes progressive resistance training improves physical function and reduces disability compared with low-intensity home exercise among physically frail elderly patients with hip fracture.

DESIGN, SETTING, AND PATIENTS

Randomized controlled trial conducted between August 1998 and May 2003 among 90 community-dwelling women and men aged 65 years or older who had had surgical repair of a proximal femur fracture no more than 16 weeks prior and had completed standard physical therapy.

INTERVENTION

Participants were randomly assigned to 6 months of either supervised physical therapy and exercise training (n = 46) or home exercise (control condition; n = 44).

MAIN OUTCOME MEASURES

Primary outcome measures were total scores on a modified Physical Performance Test (PPT), the Functional Status Questionnaire physical function subscale (FSQ), and activities of daily living scales. Secondary outcome measures were standardized measures of skeletal muscle strength, gait, balance, quality of life, and body composition. Participants were evaluated at baseline, 3 months, and 6 months.

RESULTS

Changes over time in the PPT and FSQ scores favored the physical therapy group (P =.003 and P =.01, respectively). Mean change (SD) in PPT score for physical therapy was +6.5 (5.5) points (95% confidence interval [CI], 4.6-8.3), and for the control condition was +2.5 (3.7) points (95% CI, 1.4-3.6 points). Mean change (SD) in FSQ score for physical therapy was +5.2 (5.4) points (95% CI, 3.5-6.9) and for the control condition was +2.9 (3.8) points (95% CI, 1.7-4.0). Physical therapy also had significantly greater improvements than the control condition in measures of muscle strength, walking speed, balance, and perceived health but not bone mineral density or fat-free mass.

CONCLUSION

In community-dwelling frail elderly patients with hip fracture, 6 months of extended outpatient rehabilitation that includes progressive resistance training can improve physical function and quality of life and reduce disability compared with low-intensity home exercise.

Impact of achilles tendon lengthening on functional limitations and perceived disability in people with a neuropathic plantar ulcer

OBJECTIVE

An Achilles tendon-lengthening (ATL) procedure is effective at reducing ulcer recurrence in patients with diabetes, peripheral neuropathy, and a plantar ulcer, but its effects on functional limitations and perceived disability are unknown. The purpose of this study is to report the effects of an ATL and total contact casting (TCC) on the functional limitations and perceived disability of patients with neuropathic plantar ulcers.

RESEARCH DESIGN AND METHODS

Twenty-eight subjects with a mean age of 55 +/- 10 years and a BMI of 33 +/- 6 kg/m(2) participated. All subjects had a history of diabetes, loss of protective sensation, limited ankle motion, and a recurrent forefoot ulcer. Subjects were randomized into two groups: an ATL group (n = 14), who received treatment of ATL, and TCC and a TCC group (n = 14), who received TCC only. Subjects completed a modified physical performance test (PPT) and the SF-36 Health Survey before treatment, after primary treatment and healing of the plantar forefoot ulcer, and 8 months after initial ulcer healing.

RESULTS

There were no significant changes in functional limitations as measured by the PPT between groups or over time. The physical summary score of the SF-36 decreased slightly from before treatment to 8 months after initial ulcer healing in the ATL group (35 +/- 7 to 31 +/- 6), whereas the TCC group score increased during this time (34 +/- 8 to 39 +/- 11; P < 0.05).

CONCLUSIONS

The ATL resulted in no measurable change in functional limitations, but patients receiving an ATL and TCC reported lower physical functioning at 8 months after initial ulcer healing than subjects receiving TCC alone and may require additional physical therapy to address this perceived disability.

Effect of Achilles tendon lengthening on neuropathic plantar ulcers. A randomized clinical trial

BACKGROUND

Limited ankle dorsiflexion has been implicated as a contributing factor to plantar ulceration of the forefoot in diabetes mellitus. The purpose of this study was to compare outcomes for patients with diabetes mellitus and a neuropathic plantar ulcer treated with a total-contact cast with and without an Achilles tendon lengthening. Our primary hypothesis was that the Achilles tendon lengthening would lead to a lower rate of ulcer recurrence.

METHODS

Sixty-four subjects were randomized into two treatment groups, immobilization in a total-contact cast alone or combined with percutaneous Achilles tendon lengthening, with measurements made before and after treatment, at the seven-month follow-up examination, and at the final follow-up evaluation (a mean [and standard deviation] of 2.1 +/- 0.7 years after initial healing). There were thirty-three subjects in the total-contact cast group and thirty-one subjects in the Achilles tendon lengthening group. There were no significant differences in age, body-mass index, or duration of diabetes between the groups. Outcome measures were time to healing of the ulcer, ulcer recurrence rate, range of dorsiflexion of the ankle, peak torque (strength) of the plantar flexor muscles, and peak plantar pressures on the forefoot.

RESULTS

Twenty-nine (88%) of thirty-three ulcers in the total-contact cast group and all thirty ulcers (100%) in the Achilles tendon lengthening group healed after a mean duration (and standard deviation) of 41 +/- 28 days and 58 +/- 47 days, respectively (p > 0.05). (One patient in the Achilles tendon lengthening group died before treatment was completed.) In the first seven months of follow-up, sixteen (59%) of the twenty-seven patients in the total-contact cast group who were available for follow-up and four (15%) of the twenty-seven patients in the Achilles tendon lengthening group who were available for follow-up had an ulcer recurrence (p = 0.001). At the time of the two-year follow-up, twenty-one (81%) of the twenty-six patients in the total-contact cast group and ten (38%) of the twenty-six patients in the Achilles tendon lengthening group had ulcer recurrence (p = 0.002). Compared with the group treated with the total-contact cast, the group treated with Achilles tendon lengthening had increased dorsiflexion and it remained increased at seven months (p < 0.001). Plantar flexor peak torque also decreased after Achilles tendon lengthening (p < 0.004), but it returned to baseline after seven months. Peak plantar pressures on the forefoot during barefoot walking were reduced (p < 0.0002) following Achilles tendon lengthening yet returned to baseline values within seven months after treatment.

CONCLUSIONS

All ulcers healed in the Achilles tendon lengthening group, and the risk for ulcer recurrence was 75% less at seven months and 52% less at two years than that in the total-contact cast group. Achilles tendon lengthening should be considered an effective strategy to reduce recurrence of neuropathic ulceration of the plantar aspect of the forefoot in patients with diabetes mellitus and limited ankle dorsiflexion (</=5 degrees ).

Effects of exercise training added to ongoing hormone replacement therapy on bone mineral density in frail elderly women

OBJECTIVES

To determine whether exercise training added to ongoing hormone replacement therapy (HRT) increases bone mineral density (BMD) in physically frail elderly women.

DESIGN

Prospective controlled trial.

SETTING

University-based research center.

PARTICIPANTS

Twenty-eight women on HRT, aged 75 and older with physical frailty.

INTERVENTIONS

Participants were assigned to 9 months of supervised (EXER) or home (HOME) exercise. The EXER program started with physical therapy and gradually incorporated resistance and endurance training. The HOME program consisted of flexibility exercises.

MEASUREMENTS

Changes in BMD and body composition.

RESULTS

There were larger increases in lumbar spine BMD in response to EXER than with HOME (3.5% vs 1.5%, P =.048), with a trend for larger increases in total body BMD (1.5% vs 0.2%, P =.058). There were no significant between-group differences in hip BMD. The EXER group had decreases in weight (-2.2 +/- 0.3 kg, P =.010) and fat mass (-2.7 +/- 0.4 kg, P =.018) and increases in muscle strength (9-30%, P <.05).

CONCLUSION

In physically frail elderly women on HRT, relatively vigorous exercise training significantly increased lumbar spine BMD. The improved BMD and strength in response to exercise could reduce fracture risk in frail women already on HRT.

Effects of exercise training on frailty in community-dwelling older adults: results of a randomized, controlled trial

OBJECTIVES

Although deficits in skeletal muscle strength, gait, balance, and oxygen uptake are potentially reversible causes of frailty, the efficacy of exercise in reversing frailty in community-dwelling older adults has not been proven. The aim of this study was to determine the effects of intensive exercise training (ET) on measures of physical frailty in older community-dwelling men and women.

DESIGN

Randomized controlled trial.

SETTING

Medical school research center.

PARTICIPANTS

One hundred fifteen sedentary men and women (mean age +/- standard deviation = 83 +/- 4) with mild to moderate physical frailty, as defined by two of the following three criteria: Modified Physical Performance Test (modified PPT) score between 18 and 32, peak oxygen uptake (VO2 peak) between 10 and 18 mL/kg/min, and self-report of difficulty or assistance with one basic activity of daily living (ADL), or two instrumental ADLs.

INTERVENTION

Participants were randomly assigned to a control group that performed a 9-month low-intensity home exercise program (control) or an exercise-training program (ET). The control intervention primarily consisted of flexibility exercises. ET began with 3 months of flexibility, light-resistance, and balance training. During the next 3 months, resistance training was added, and, during the next 3 months, endurance training was added.

MEASUREMENTS

Modified PPT score, VO2 peak, performance of ADLs as measured by the Older Americans Resources and Services instrument, and the Functional Status Questionnaire (FSQ).

RESULTS

ET resulted in significantly greater improvements than home exercise in three of the four primary outcome measures. Adjusted 95% confidence bounds on the magnitude of improvement in the ET group compared with the control group were 1.0 to 5.2 points for the modified PPT score, 0.9 to 3.6 mL/kg/min for VO2 peak, and 1.6 to 4.9 points for the FSQ score.

CONCLUSIONS

Our results show that intensive ET can improve measures of physical function and preclinical disability in older adults who have impairments in physical performance and oxygen uptake and are not taking hormone replacement therapy better than a low-intensity home exercise program.

Low-intensity exercise as a modifier of physical frailty in older adults

OBJECTIVE

To examine the effects of a 3-month low-intensity exercise program on physical frailty.

DESIGN

Randomized clinical trial.

SETTING

Regional tertiary-care hospital and academic medical center with an outpatient rehabilitation fitness center.

PARTICIPANTS

Eighty-four physically frail older adults (mean age, 83 +/- 4 yrs).

INTERVENTION

Three-month low-intensity supervised exercise (n = 48) versus unsupervised home-based flexibility activities (n = 36).

MAIN OUTCOME MEASURES

Physical performance test, measures of balance, strength, flexibility, coordination, speed of reaction, peripheral sensation.

RESULTS

Significant improvement was made by the exercise group on our primary indicator of frailty, a physical performance test (PPT) (29 +/- 4 vs 31 +/- 4 out of a possible 36 points), as well as many of the risk factors previously identified as contributors to frailty; eg, reductions in flexibility, strength, gait speed, and poor balance. Although the home exercise control group showed increases in range of motion, the improvements in flexibility did not translate into improvements in physical performance capacity as assessed by the PPT.

CONCLUSIONS

Our results suggest that physical frailty is modifiable with a program of modest activities that can be performed by virtually all older adults. They also indicate that exercise programs consisting primarily of flexibility activities are not likely to reverse or attenuate physical frailty. Although results suggest that frailty is modifiable, it is not likely to be eliminated with exercise, and efforts should be directed toward preventing the condition.

Physical and performance measures for the identification of mild to moderate frailty

BACKGROUND

The relative importance and association of factors contributing to physical frailty in elderly persons are unclear.

METHODS

Physical measures of upper and lower extremity strength, range of motion, balance, coordination, sensation, and gait were evaluated in relation to scores obtained on a 36-point physical performance test (PPT) in 107 elderly subjects.

RESULTS

Scores on the PPT were significantly associated with the measures of strength and balance, gait, several range of motion values, and sensation. Subjects were also grouped according to score on the PPT as not frail (32-36 points), mildly frail (25-31 points), or moderately frail (17-24 points). ANOVA followed by Bonferroni post hoc analyses were used to examine the relationships of physical measures to this index of frailty. Balance measures, an obstacle course, the Berg scale, the full tandem portion of the Romberg test, and fast gait speed were significantly different among the three groups. Multiple stepwise regression analyses indicated that the strongest combination of variables, explaining 73% of all the variance in the PPT, included obstacle course performance, hip abduction strength, the semitandem portion of the Romberg test, and coordination (pegboard).

CONCLUSIONS

Results provide further insight into the relative importance of factors that contribute to frailty and factors that should be considered in treatment planning for the remediation of physical frailty in old adults.

Effects of a tendo-Achilles lengthening procedure on muscle function and gait characteristics in a patient with diabetes mellitus

STUDY DESIGN

Case report with repeated measures.

OBJECTIVES

To describe the effects of a tendo-Achilles lengthening (TAL) and total contact casting (TCC) on wound healing, motion, plantar pressure, and function in a patient with diabetes mellitus, peripheral neuropathy, neuropathic ulcer, and limited dorsiflexion range of motion (DFROM).

BACKGROUND

Limited DFROM has been associated with increased forefoot pressures and skin breakdown. A TAL was expected to increase DFROM and reduce forefoot pressures during walking, but the influence on muscle performance and function was unknown.

METHODS AND MEASURES

The patient was a 42-year-old man with a 20-year history of type 1 diabetes (NIDDM) and a recurrent neuropathic plantar ulcer. Outcome measures were DFROM, isokinetic plantar flexor muscle peak torque, in-shoe and barefoot peak plantar pressure, physical performance test (PPT) score, and peak ankle and hip moments during walking obtained from an automated gait analysis. All tests were completed pre-TAL, 8 weeks post-TAL (after immobilization in a TCC), and 7 months post-TAL.

RESULTS

The wound healed in 40 days. The TAL resulted in a sustained increase in DFROM (0 to 18 degrees). Plantar flexor peak torque was reduced by 21% 8 weeks after the TAL compared with the torque before surgery but recovered fully at 7 months. Seven months following TAL, in-shoe forefoot peak plantar pressure was reduced by 55%, barefoot pressure decreased by 14%, PPT score increased by 24%, peak ankle plantar flexor moment remained decreased by 30%, and the peak hip flexor moment increased by 41% during walking.

CONCLUSION

For this patient, a TAL resulted in short-term deficits in peak plantar flexor torque, but a 7-month follow-up showed improvements in ankle DFROM, walking ability, and a decrease in forefoot in-shoe peak plantar pressure.

Timing of peak plantar pressure during the stance phase of walking. A study of patients with diabetes mellitus and transmetatarsal amputation

High plantar pressures contribute to skin breakdown in patients with diabetes mellitus and peripheral neuropathy. The primary purpose of this study was to determine the point during the stance phase of walking that corresponds with forefoot peak plantar pressures. Results indicate that peak plantar pressures occurred at 80% +/- 5% of the stance phase of gait in subjects with diabetes and transmetatarsal amputation, as well as in control subjects. Improved methods of footwear design or walking strategies proposed to patients should focus on the demands of the foot during the late stance phase of walking in order to increase available weightbearing area or to decrease forces, which will minimize plantar pressures and reduce trauma to the neuropathic foot.

Recognition and management of acute neuropathic (Charcot) arthropathies of the foot and ankle

STUDY DESIGN

Review of selected literature describing the outcomes related to the management of acute Charcot foot arthropathies in patients with diabetes mellitus.

OBJECTIVE

To familiarize the rehabilitation specialist with the general principles of nonsurgical management for patients with acute neuropathic arthropathies of the foot and ankle.

BACKGROUND

Neuropathic (Charcot) arthropathy of the foot or ankle is the most destructive and disabling chronic complication of all diabetic foot disease.

METHODS AND MEASURES

We discuss the clinical presentation and the role that orthopaedic and sports physical therapists may have in identifying and preventing complications and the long-term disability associated with these arthropathies. We summarize the outcomes of 15 published reports from 1985-1999 located using the MEDLINE database from 1966-present. Studies were selected and included if the authors reported on (1) 2 or more patients with diabetes mellitus and acute Charcot arthropathies; (2) the short-term or long-term outcomes, including the length of follow-up; and (3) the pattern or location of the arthropathy. The short-term outcomes (percentage of patients healed, average time to healing) and long-term outcomes (percentage in whom treatment failed, amputation, disability) after treatment by immobilization alone or immobilization after surgery were reviewed and summarized.

RESULTS

The prognosis for an individual with severe neuropathic skeletal foot deformities is poor. Eleven deaths (3.65%) in 301 patients were reported within the average follow-up period of 2.5 years after treatment for Charcot arthropathy. Partial or complete foot amputation occurred in 20 (6.6%) of 301, whereas 83 (28%) of 301 patients reviewed had mobility limitations or required ankle-foot orthoses or permanent bracing or assistive devices for ambulation at the time of follow-up.

CONCLUSION

Rehabilitation specialists can improve the short-term outcomes and limit the long-term disabilities in patients with diabetes mellitus and peripheral neuropathy. Early recognition and prompt immobilization are the basic principles of nonsurgical management that influence therapeutic outcome.

Healing times of pedal ulcers in diabetic immunosuppressed patients after transplantation

OBJECTIVE

To compare the healing time of neuropathic plantar ulcers treated by total-contact casting (TCC) in diabetic, immunosuppressed patients after organ transplantation with the healing time of plantar ulcers in control nonimmunosuppressed patients.

DESIGN

A case-control design with the control group matched for age, race, sex, body dimensions (height, weight, and body mass index), presence of sensory neuropathy, foot deformity presence and location, and pedal ulcer area and depth.

SETTING

An outpatient physical therapy clinic in a regional tertiary-care hospital and academic medical center.

PARTICIPANTS

Nine patients with chronic diabetes mellitus and a previous organ transplantation who were currently receiving lifelong immunosuppressive drug therapy were treated for a neuropathic plantar ulcer by means of TCC. Fourteen group-matched control subjects with diabetes mellitus and a plantar ulcer but who had never had an organ transplantation and were not taking immunosuppressive agents were also studied.

INTERVENTIONS

TCC with partial weight-bearing using an assistive device until ulcers healed.

MAIN OUTCOME MEASURE

Healing time was defined as the number of days in the total-contact cast until the skin completely closed.

RESULTS

All diabetic foot ulcers healed with casting. Immunosuppressed/transplanted patients healed in a mean time of 111 +/- 25 days; ulcers of control subjects healed in 47 +/- 18 days (p < .05). All patients returned to ambulation using prescribed therapeutic footwear. None of the patients required a lower extremity amputation throughout the follow-up period.

CONCLUSIONS

TCC is a highly effective and rapid method of healing neuropathic pedal ulcers in diabetic immunosuppressed/transplantation patients, although it may take several weeks longer than it would for patients who were not immunocompromised.

Resistance exercise training increases mixed muscle protein synthesis rate in frail women and men >/=76 yr old

Muscle atrophy (sarcopenia) in the elderly is associated with a reduced rate of muscle protein synthesis. The purpose of this study was to determine if weight-lifting exercise increases the rate of muscle protein synthesis in physically frail 76- to 92-yr-old women and men. Eight women and 4 men with mild to moderate physical frailty were enrolled in a 3-mo physical therapy program that was followed by 3 mo of supervised weight-lifting exercise. Supervised weight-lifting exercise was performed 3 days/wk at 65-100% of initial 1-repetition maximum on five upper and three lower body exercises. Compared with before resistance training, the in vivo incorporation rate of [(13)C]leucine into vastus lateralis muscle protein was increased after resistance training in women and men (P < 0.01), although it was unchanged in five 82 +/- 2-yr-old control subjects studied two times in 3 mo. Maximum voluntary knee extensor muscle torque production increased in the supervised resistance exercise group. These findings suggest that muscle contractile protein synthetic pathways in physically frail 76- to 92-yr-old women and men respond and adapt to the increased contractile activity associated with progressive resistance exercise training.

Peak aerobic power is an important component of physical performance in older women

BACKGROUND

The purpose of this study was to determine the relationship between peak aerobic power (VO2peak) and performance on a modified Physical Performance Test (modified PPT) in older women.

METHODS

One hundred one women aged 75 years and older seeking enrollment in randomized, controlled trials of exercise and/or hormone replacement therapy were recruited from the community-at-large and from congregate living sites. Measures obtained included VO2peak, a modified PPT, and self-reports about performance of activities of daily living.

RESULTS

Simple regression analysis demonstrated that VO2peak was associated with total PPT score (r =.53, p <.001), gait speed (r =.44, p <.001), time to arise from a chair five times (r =.43, p = <.001), and time to climb one flight of stairs (r =.36, p =.007). Multiple regression analysis revealed that the relationships between VO2peak and total modified PPT score, gait speed, chair rise time, and time to climb one flight of stairs were independent of age.

CONCLUSIONS

Peak aerobic power is a significant independent predictor of performance on a standardized test of physical function in older women and is an important component of physical frailty in this population.

Healing times of diabetic ulcers in the presence of fixed deformities of the foot using total contact casting

In a diabetic foot, ulcers can lead directly to the loss of a limb, and they may be life threatening if the patient is not provided effective intervention directed at healing. This study reports on the healing times of diabetic neuropathic plantar ulcers in the presence of fixed deformities of the foot using the ambulatory method of total contact casting (TCC). In this study, 21 subjects with chronic diabetes mellitus, plantar ulcers, and fixed deformities of the foot were put in casts, and their progress was followed until the ulcers were completely healed. Results indicated that all of the ulcers healed. The average time to healing was 67 +/- 29 days. Ulcers located in the forefoot, midfoot, and rearfoot healed in an average of 35 +/- 12 days, 73 +/- 28 days, and 90 +/- 12 days, respectively. The location of the ulcer and the presence and location of a fixed deformity of the foot strongly correlated with and was predictive of healing time using TCC. The location of the ulcers and the location of the fixed deformities of the foot should always be considered by providers of rehabilitation who treat diabetic neuropathic foot ulcers using TCC.

Acute Charcot arthropathy in patients with diabetes mellitus: healing times by foot location

Foot deformity and lower extremity dysfunction are debilitating complications of diabetes mellitus which often lead to significant permanent disability. Acute diabetic neuroarthropathy (Charcot arthropathy) directly leads to foot deformity, subsequent lower-extremity complications and may lead to lower-extremity amputation, if not identified and managed appropriately. The purpose of this study is to report the healing times of acute-onset neuropathic arthropathies (fractures, joint subluxations or dislocations) in individuals with diabetes mellitus by foot location using the ambulatory method of total-contact casting (TCC). In addition, the identification of critical subject characteristic which influence healing outcomes were determined. The results indicate all (100%) of the acute (Charcot) fractures, subluxations, or dislocations healed in an average of 86+/-45 days. Acute Charcot arthropathies of the ankle, hindfoot, or midfoot take longer to heal by TCC than arthropathies localized to the forefoot. Adherence to partial weight bearing with assistive devices during casting and early institution of cast immobilization are critical factors associated with shorter healing times using TCC. Physicians, rehabilitation specialists and third-party payers should be aware of the length of time required to heal acute Charcot foot arthropathies at all locations of the foot using TCC.

Unilateral hip rotation range of motion asymmetry in patients with sacroiliac joint regional pain

STUDY DESIGN

A cross-sectional study was used to determine whether limited range of motion in the hip was present in 100 patients--one group with unspecified low back pain and another group with signs suggesting sacroiliac joint dysfunction.

OBJECTIVES

To determine whether a characteristic pattern of range of motion in the hip is related to low back pain in patients and to determine whether such a pattern is associated with and without signs of sacroiliac joint dysfunction.

SUMMARY OF BACKGROUND DATA

The sacroiliac joint is often considered a potential site of low back pain. Problems with the sacroiliac joint, as well as with the low back, have often been related to reduced or asymmetric range of motion in the hip. The correlation between sacroiliac joint dysfunction and hip range of motion, however, has not been thoroughly evaluated with reliable tests in a population of patients with low back pain.

METHODS

Passive hip internal and external rotation goniometric measurements were taken by a blinded examiner, while a separate examiner evaluated the patient for signs of sacroiliac joint dysfunction. Patients with sacroiliac joint dysfunction were further classified as having a left or a right posteriorly tilted innominate.

RESULTS

The patients with low back pain but without evidence of sacroiliac joint dysfunction had significantly greater external hip rotation than internal rotation bilaterally, whereas those with evidence of sacroiliac joint dysfunction had significantly more external hip rotation than internal rotation unilaterally, specifically on the side of the posterior innominate.

CONCLUSIONS

Clinicians should consider evaluating for unilateral asymmetry in range of motion in the hip in patients with low back pain. The presence of such asymmetry in patients with low back pain may help identify those with sacroiliac joint dysfunction.

Total contact casting for diabetic neuropathic ulcers

Despite its limited therapeutic use, several research reports indicate that TCC is currently the most rapid and effective technique for healing diabetic neuropathic ulcers. Skilled application and careful follow-up of the wound are necessary to avoid complications and minimize the risks for reulceration. As more clinicians adopt this form of therapy, the successful treatment of neuropathic ulcers using TCC should result in a lower incidence of infection, hospitalization and lost income in patients with chronic sensory neuropathies.

High-voltage galvanic stimulation on wound healing in guinea pigs: longer-term effects

The purpose of this investigation was to determine the effects of high-voltage stimulation (HVS) on wound tensile strength properties and wound closure (histology). Eighteen mature guinea pigs with full-thickness incisions were treated with HVS for 45 minutes daily for 2 weeks; 9 animals were studied after the 14 days of treatment and the remaining 9 were studied 2 weeks later. Five animals (10 wounds) served as controls at each time period. After 2 or 4 weeks, treated and untreated skin was harvested, tested to failure, and prepared for histological examination. Two-week-treated and control wounds had comparable values for peak force to failure, elongation, and energy absorbed to failure. Epithelialization was more advanced in treated animals at 14 days (p < .05). There was a trend (p = .068) toward stronger wounds in 4-week-treated animals (maximum load to failure), but not differences were observed between controls and treated groups for elongation or energy absorbed to failure. Dermal healing appeared to be more advanced in treated animals at 30 days. Although peak force to failure was almost 500g higher for treated guinea pigs after 2 weeks of treatment and more than 700g higher than controls after 4 weeks, mean data were highly variable, so the hypothesis that HVS augments wound strength could not be accepted. It is difficult, however, not to assign clinical significance to the findings.

The relationship of strength to function in the older adult

Reduced lower extremity strength has been associated with reduction in gait speed, balance, stair-climbing ability, and getting up from a seated position. The relationship of lower extremity strength and the ability to accomplish selected functional activities was examined in 16 healthy but frail older adults ranging in age from 75 to 88 years (mean = 80.9 years). The following measures were obtained for each subject: preferred gait speed under laboratory and free walking conditions, 5 timed chair stand-ups, and time to complete an obstacle course. Strength measures of the hip extensors, hip abductors, knee extensors, planter flexors, and dorsiflexor muscle groups were obtained using a hand-held dynamometer. The relationship between the time to complete the functional activities and each of the strength variables was determined using Pearson product moment correlations. In addition, performance was examined in relation to various combinations of strength measures (e.g., hip and knee extension). Weak, nonsignificant hip, knee and ankle strength/functional activity relationships were found for all of the variables examined. When hip extension, knee extension, and ankle plantar flexion strength values were combined and normalized to body weight, a significant strength-to-functional activity relationship was found for 14" chair stand-ups (r = .636, p < .01). When values for quadriceps strength and gait speed for 35 adults ranging in age from 60-72 years were compared to those for 75-88 year olds, marked differences emerged. A more significant relationship between knee extension force and gait speed was observed for the younger adults (r = .528 vs r = .353).(ABSTRACT TRUNCATED AT 250 WORDS)

Incidence of skin breakdown and higher amputation after transmetatarsal amputation: implications for rehabilitation

The purpose of this study of patients with transmetatarsal amputation (TMA) is to describe multiple patient characteristics, including the incidence of subsequent skin breakdown and higher amputation, that may influence rehabilitation treatment and outcomes. Data were gathered on all patients having a TMA at this facility between April 1989 and September 1993. One hundred twenty TMAs were performed on 107 patients with a mean age of 62.4 +/- 13.8 years. There were 55 men and 52 women. Thirteen patients (12%) had a bilateral TMA. Twenty-nine patients (27%) developed skin breakdown. Of these, 48% occurred within the first 3 months after surgery. Thirty patients (28%) required a higher amputation. Of these, 60% occurred in the first month after TMA. In addition, this group of patients had a high incidence of diabetes mellitus (77%), hypertension (54%), electrocardiogram (EKG) abnormalities (60%), congestive heart failure (22%), and prior ipsilateral vascular surgery (51%). These results indicate that patients with TMA often present with a complicated medical condition and that they are at high risk of skin breakdown or higher amputation, especially in the first 3 months after surgery. The investigators conclude that patients with TMA may benefit from a rehabilitation program emphasizing protection of the residuum during their return to functional activities. Additional research is needed to determine optimal acute and long-term rehabilitation of patients with TMA.

Rehabilitation factors following transmetatarsal amputation

Despite the occurrence of approximately 10,000 transmetatarsal amputations (TMAs) a year in the United States, there are few reports describing rehabilitation for this patient group. The purposes of this clinical perspective are (1) to identify common problems encountered during rehabilitation of patients with TMA, (2) to identify factors that may contribute to these problems, and (3) to propose methods to manage these problems. A review of the literature and biomechanical models of the residuum, footwear, and orthotic devices are provided to help accomplish these purposes. Common problems encountered during rehabilitation of patients with TMA are skin breakdown and instability during functional activities. Decreased foot length and peripheral neuropathies appear to contribute to these problems. Solutions focus on attempting to provide a substitute for the plantar-flexor lever arm and protection of the insensitive residual foot. Suggestions for additional research are presented.

Hip and ankle walking strategies: effect on peak plantar pressures and implications for neuropathic ulceration

Treatment of neuropathic plantar ulcers often is directed at reducing excessive, repeated peak plantar pressures (PPP). The purposes of this study were to determine whether instructing a subject to walk using a hip strategy would reduce forefoot PPP and change the kinematics of walking during a single session of testing. Thirteen subjects, 7 with peripheral neuropathy and a history of a recent plantar ulcer, and 6 controls participated. PPPs were measured with an in-shoe pressure monitoring system. Kinematics were measured with a computer-assisted motion analysis system. After data were collected as subjects walked using their normal walking pattern, subjects were instructed to walk using the hip strategy by decreasing their push-off, pulling their leg forward from their hips, decreasing step length, and maintaining their normal walking velocity. Compared with using the normal (ankle) strategy, using the hip strategy showed a significant 27% decrease in forefoot PPP and a 24% increase in heel PPP. Kinematic changes were decreased plantar flexion angular velocity, hip extension range-of motion (ROM), and step length, increased dorsiflexion ROM, and hip flexion ROM, but no change in walking velocity. These findings indicate that a change in walking pattern can result in lower forefoot PPP during a single session. Assuming patients can maintain the alterations in their walking pattern, these adaptations may help to heal plantar ulcers in some patients with peripheral neuropathy.

Quadriceps femoris muscle resistance to fatigue using an electrically elicited fatigue test following intense endurance exercise training

BACKGROUND AND PURPOSE

Electrical stimulation has been used to assess skeletal muscle resistance to fatigue. The purpose of this study was to test the hypothesis that 12 weeks of intense endurance exercise training on a bicycle ergometer would reduce the percentage of decline in quadriceps femoris muscle torque during an electrically elicited fatigue test.

SUBJECTS AND METHODS

Eleven nondisabled subjects performed 12 weeks of high-intensity endurance exercise training, and 6 subjects served as controls and did not exercise. Two electrically elicited fatigue tests, one with and one without prior voluntary fatiguing exercise, were administered to each subject before and after the 12-week training period.

RESULTS

The percentage of decline in peak torque of the quadriceps femoris muscle over 50 electrically elicited muscle contractions did not change as a result of endurance exercise training, despite significant improvements in maximal oxygen consumption and quadriceps femoris muscle endurance. The recovery of maximal isometric torque immediately after exhausting voluntary exercise followed by electrical stimulation was significantly greater after 12 weeks of intense exercise training.

CONCLUSION AND DISCUSSION

The percentage of decline in peak torque during an electrically elicited fatigue test does not detect improvements in quadriceps femoris muscle endurance induced by endurance exercise training. The percentage of initial torque recovered immediately after fatiguing exercise, however, is improved by endurance training. [Sinacore Dr, Jacobson RB, Delitto A. Quadriceps femoris muscle resistance to fatigue using an electrically elicited fatigue test following intense endurance exercise training.

Shin splints and forefoot contact running: a case report

Many athletes develop shin splints after athletic activity. The purpose of this case report is to describe the treatment of a patient with posteromedial tibial pain (shin splints) who habitually ran with a forefoot contact running style. The 20-year-old male patient, who played volleyball and basketball about 7 hours a week, complained of pain in the middle one-third of the posteromedial tibia after an acute but prolonged episode of running. Routine observational analysis and in-shoe pressure analysis of the patient's running style showed that he habitually ran on his toes with an absence of heelstrike (forefoot contact running). After instructing the patient on heel-toe running, he no longer complained of posteromedial tibial bone pain. Several possible reasons are proposed for the reduction of leg pain following cessation of forefoot contact running. This case report proposes forefoot contact running as a possible contributor to posteromedial shin splints and that a change in running style may be the optimal treatment for some patients.

Recovery from a 1-minute bout of fatiguing exercise: characteristics, reliability, and responsiveness

BACKGROUND AND PURPOSE

The purposes of this study were (1) to describe the characteristics of recovery of peak torque after a 1-minute bout of isokinetic exercise of the quadriceps femoris muscle, (2) to determine the short-term reliability of the recovery of peak torque, and (3) to determine whether the recovery of peak torque more closely associates with maximal endurance exercise capacity than does the decline in peak torque at the end of the fatigue test.

SUBJECTS

Thirty-three nondisabled subjects, ranging in age from 23 to 34 years (X = 27, SD = 3.4), participated in the reliability portion (phase 1) of the study. A different group of 21 nondisabled subjects, ranging in age from 21 to 47 years (X = 27.5, SD = 5.2), participated in the correlational portion (phase 2) of the study.

METHODS

The short-term reliability of percentage of decline in peak torque and recovery of peak torque was assessed in phase 1. Each subject performed two quadriceps femoris muscle fatigue tests (test-retest) on an isokinetic dynamometer. In phase 2, each subject performed a single fatigue test and a test of maximal oxygen uptake (VO2max) to examine the relationships between VO2max and percentage of decline in peak torque at the end of the fatigue test and recovery of peak torque.

RESULTS

Intraclass correlation coefficient values at every 30-second interval during recovery were acceptable (ICC = .67-.87), indicating recovery of peak torque is a consistent measure of quadriceps femoris muscle performance. A high negative correlation (r = -.84) was found between the percentage of decline at 30 seconds of recovery and VO2max, but a lower negative correlation (r = -.48) was found between the percentage of decline in torque at the end of the fatigue test and VO2max.

CONCLUSION AND DISCUSSION

These results suggest recovery of peak torque is a reliable measure of muscle performance and closely associates with maximal aerobic exercise capacity.

The role of skeletal muscle in glucose transport, glucose homeostasis, and insulin resistance: implications for physical therapy

Skeletal muscle has a fundamentally important role in the maintenance of normal glucose homeostasis and in regulating whole-body carbohydrate metabolism. In this review, we discuss the regulation of skeletal muscle glucose transport by muscular activity and inactivity. A large number of patients routinely seen by physical therapists exhibit some form of skeletal muscle insulin resistance. Therefore, we discuss how skeletal muscle insulin resistance can be localized to a relatively small muscle mass, or in other circumstances can affect a large proportion of the muscle mass leading to disturbances in whole-body glucose homeostasis. We review the mechanisms and regulation of skeletal muscle glucose transport as background for understanding how defects in this process may contribute to the underlying pathogenesis of insulin resistance. Research into the events regulating glucose entry into skeletal muscles has considerable impact on how physical therapy exercise prescriptions may benefit patients with disturbances in carbohydrate metabolism. With an understanding of the principles of proper exercise prescription, physical therapists can use exercise training as a primary therapeutic intervention to improve local muscle and whole-body glucose utilization, and thereby minimize insulin resistance.

Histochemical and physiological correlates of training- and detraining-induced changes in the recovery from a fatigue test

BACKGROUND AND PURPOSE

The primary purpose of this study was to evaluate the effects of endurance training and detraining on the development of and recovery from fatigue induced by isokinetic exercise. It was our hypothesis that the rate of recovery from fatigue would correlate with maximal oxygen uptake (VO2max). A secondary purpose was to determine whether changes in the development of fatigue and in the time course of recovery that occur with alterations in training status correlate with shifts in the proportions of type IIa and type IIb muscle fibers.

SUBJECTS AND METHODS

Four subjects with no regular endurance exercise training participated in a 12-week program of intense endurance exercise training, and 6 endurance-trained subjects stopped all exercise training for 12 weeks. In addition, 11 subjects performed a single isokinetic fatigue test with recovery and a graded treadmill or bicycle ergometer test to determine VO2max.

RESULTS

Maximal oxygen uptake increased 24% (SD = 10%) in response to the exercise training program and decreased 17% (SD = 6%) with detraining. The percentage of type IIa and type IIb muscle fibers changed with endurance training and detraining. The percentage of decline in torque during a 60-second isokinetic exercise test was unaffected by endurance training or detraining; however, there was a significant change in recovery of torque.

CONCLUSION AND DISCUSSION

The results demonstrate a positive correlation (r = .75) between the percentage of reduction in torque at 30 seconds of recovery and the change in the proportion of type IIb fibers with both training and detraining. The results also demonstrate a high, negative correlation (r = -.84) between the percentage of reduction in torque at 30 seconds of recovery and VO2max. These results suggest the recovery of muscle torque reflects both the training- and detraining-induced changes in the proportion of type IIa and type IIb muscle fibers and maximal aerobic exercise capacity.

Type II fiber activation with electrical stimulation: a preliminary report

Electrical stimulation to augment or maintain muscle performance has been well documented. The purpose of this preliminary report is to present the results of a single-case study conducted to determine the order of activation of skeletal muscle fibers as a result of electrical stimulation. The subject's quadriceps femoris muscles were electrically stimulated at 80% of maximal isometric torque. Pre-stimulation and immediate post-stimulation muscle biopsy samples were obtained, and a modification of the glucogen-depletion method was used to determine activation of muscle fibers. The pre-stimulation muscle biopsy sample demonstrated uniform periodic acid-Schiff (PAS)-positive staining in all fiber types, whereas the post-stimulation muscle biopsy sample showed glycogen depletion of type II muscle fibers. The most PAS-negative muscle fibers were type IIa skeletal muscle fibers. The results of this single-case study provide evidence that electrical stimulation, as described, selectively activates type II skeletal muscle fibers. The implication of this finding is that, in many chronic diseases, type II fibers are selectively and preferentially affected. Electrical stimulation may be a clinically viable technique to use in patients with type II fiber involvement.

Reliability of a diabetic foot evaluation

The purpose of this study was to establish the interrater and intrarater reliability of various ankle and foot measures common to a diabetic evaluation. Bilateral biomechanical, sensory, and wound-size measurements were obtained in 31 subjects with diabetes mellitus. Twenty-five subjects were retested by the initial examiner to determine intratester reliability, and all subjects were retested by another examiner to determine intertester reliability. Both examiners participated in an extensive training period prior to the initiation of this study to minimize variability between and within measurers. Intraclass correlation coefficients for interrater and intrarater measurements ranged from .58 to .89 and from .74 to .99, respectively. The results of this study indicate that ankle and foot measurements common to a diabetic evaluation can be taken reliably between testers. We believe extensive examiner training in these clinically relevant measures can improve reliability between testers.

Total contact casting in treatment of diabetic plantar ulcers. Controlled clinical trial

This study compared the treatment of total contact casting (TCC) with traditional dressing treatment (TDT) in the management of diabetic plantar ulcers. Forty patients with diabetes mellitus and a plantar ulcer but with no gross infection, osteomyelitis, or gangrene were randomly assigned to the TCC group (n = 21) or TDT group (n = 19). Age, sex, ratio of insulin-dependent diabetes mellitus to non-insulin-dependent diabetes mellitus, duration of diabetes mellitus, vascular status, size and duration of ulcer, and sensation were not significantly different between groups (P greater than .05). In the experimental group, TCC was applied on the initial visit, and subjects were instructed to limit ambulation to approximately 33% of their usual activity. Subjects in the control group were prescribed dressing changes and accommodative footwear and were instructed to avoid bearing weight on the involved extremity. Ulcers were considered healed if they showed complete skin closure with no drainage. Ulcers were considered not healed if they showed no decrease in size by 6 wk or if infection developed that required hospitalization. In the TCC group, 19 of 21 ulcers healed in 42 +/- 29 days; in the TDT group, 6 of 19 ulcers healed in 65 +/- 29 days. Significantly more ulcers healed (chi 2 = 12.4, P less than .05) and fewer infections developed (chi 2 = 4.1, P less than .05) in the TCC group. We conclude TCC is a successful method of treating diabetic plantar ulcers but requires careful application, close follow-up, and patient compliance with scheduled appointments to minimize complications.

Insensitivity, limited joint mobility, and plantar ulcers in patients with diabetes mellitus

The purpose of this study was to determine whether differences in sensation, ankle dorsiflexion (DF), and subtalar joint (STJ) motion exist between 1) diabetic patients with a history of plantar ulcer (DMW Group), 2) diabetic patients without a history of plantar ulcer (DMWO Group), and 3) a nondiabetic control group (NDC Group). There were 23, 23, and 24 subjects in the respective groups. The mean age for each group was 58, 63, and 60 years, respectively. The mean DF for each group was 2, 5, and 7 degrees, respectively, and the mean STJ motion was 26, 31, and 35 degrees, respectively. Mode values for sensation with Semmes-Weinstein monofilaments were 6.10, 5.07, and 4.17. The results indicate the DMW Group had significantly less sensation, DF, and STJ motion than the NDC Group (p less than .05). In the DWM Group, the ulceration was seen more often on the side with least motion. Limited DF and STJ motion may restrict the foot's ability to absorb shock and transverse rotation, contributing to the pathogenesis of plantar ulceration in the insensitive foot. Although these results demonstrate an association, not a causative relationship, we believe diabetic patients should be screened routinely for insensitivity and limited joint mobility at the feet and appropriate preventive measures should be taken.

Diabetic plantar ulcers treated by total contact casting. A clinical report

The purpose of this clinical report is to describe the healing times of plantar ulcers treated by total contact casting (TCC) in nondiabetic and diabetic patients with and without evidence of severe peripheral vascular disease. Thirty patients with 33 chronic plantar ulcers were treated by applying total contact walking casts. Results demonstrate that 27 of 33 ulcers (81.8%) healed in an average time of 43.6 days. Healing times of patients with severe peripheral vascular disease secondary to diabetes mellitus are similar to those of patients without evidence of vascular disease. These results indicate that TCC is an effective and rapid treatment for chronic plantar ulcers in patients with or without vascular compromise secondary to diabetes mellitus. In addition, the results suggest that pressure reduction on the insensitive foot should be considered in treatment.

Molded double-rocker plaster shoe for healing a diabetic plantar ulcer. A case report

The purpose of this case report is to document the successful healing of a chronic neuropathic plantar ulcer with the molded double-rocker plaster shoe (MDRPS) in a lower extremity that also had stasis changes and poor blood flow. The patient was a 67-year-old woman with insulin-dependent diabetes mellitus, insensitive feet, a right ankle-arm index of 0.48, and an ulcer beneath the right cuneonavicular joint measuring 0.94 cm2 in area and 2 mm deep. Reported onset of the ulcer was 10 months before referral for physical therapy. The MDRPS was chosen as an alternative treatment to conventional below-knee total contact casting (TCC) because of the stasis changes and fragile skin in the patient's lower extremities. The ulcer healed in 39 days after initiating treatment with the MDRPS. We consider the MDRPS the preferred treatment with those patients with neuropathic plantar ulcers who cannot tolerate the below-knee TCC.