Biomedical subjects

K S Maluf

Publications and source records attributed to K S Maluf.

5 recordsLinked to original sources

PubMed2004

Tendon Achilles lengthening for the treatment of neuropathic ulcers causes a temporary reduction in forefoot pressure associated with changes in plantar flexor power rather than ankle motion during gait.

The purposes of this study were to determine the effects of tendon Achilles lengthening (TAL) on ambulatory plantar pressures and ankle range of motion, moment, and power, and to determine whether changes in forefoot pressure after treatment of a neuropathic ulcer are related to changes in ankle dorsiflexion range of motion (DFROM) or plantar flexor (PF) power during gait. Pressure and gait tests were performed before treatment, and at 3 weeks and 8 months after treatment in two randomly assigned groups of subjects with diabetes, equinus deformity, and a neuropathic forefoot ulcer treated with TAL and total contact casting (TAL group, n=14), or total contact casting alone (TCC group, n=14). The TAL group had an initial decrease in forefoot peak pressure (PP) (27%), forefoot pressure-time integral (PTI) (42%), PF moment (53%), and PF power (65%), along with an initial increase in rear foot PP (34%), rear foot PTI (48%), and DFROM (74%). Post-surgical changes in rear foot pressure and DFROM were maintained up to 8 months after treatment with TAL, whereas forefoot pressure and PF moment and power increased significantly. Changes in forefoot pressure after treatment in either group were correlated with changes in PF power (r=0.45-0.60), but not with changes in DFROM during gait (r=-0.02-0.08). Results suggest TAL causes a temporary reduction in forefoot pressure primarily by reducing PF power during gait. The initial decrease in forefoot pressure, followed by progressive reloading of forefoot tissues as PF muscles regain strength after TAL, may help reduce the risk of ulcer recurrence in patients with diabetes.

Achilles Tendon↗

PubMed2003

Novel Award 2002. Comparison of physical activity and cumulative plantar tissue stress among subjects with and without diabetes mellitus and a history of recurrent plantar ulcers.

OBJECTIVES: To compare the amount of weight-bearing activity and estimates of cumulative plantar tissue stress between subjects with and without diabetes mellitus and a history of recurrent plantar ulcers. DESIGN: Cross-sectional study with matched groups. BACKGROUND: Weight-bearing activity among individuals with diabetes is likely to influence the amount of mechanical trauma accumulated by plantar tissues, yet activity levels have not been accounted for in previous measurements of plantar tissue stress or predictions of plantar tissue injury. METHODS: Study groups included subjects with diabetes mellitus and peripheral neuropathy, either with or without a history of recurrent plantar ulcers, and non-diabetic control subjects (n=10 per group). Pressure on the plantar foot was assessed as subjects walked at their preferred speed in the shoes they reported wearing most often each day. Physical activity was monitored over seven consecutive days using an accelerometer. The product of mean daily strides and forefoot pressure-time integral was used to estimate daily cumulative stress on the plantar forefoot. RESULTS: Subjects with diabetes and a history of recurrent plantar ulcers were 46% less active than subjects without diabetes (mean (SD)=2727 (1345) versus 5037 (2624) strides/day, P=0.04), and accumulated 41% less daily stress on the forefoot than non-diabetic and diabetic control subjects without a history of plantar ulcers (mean (SD)= 210 (134) versus 354 (118) and 354 (148) MPas/day respectively, P=0.03). CONCLUSIONS: Subjects with diabetes and a history a previous ulcers may be susceptible to plantar tissue injury even at relatively low levels of cumulative tissue stress. RELEVANCE: Changes in weight-bearing activity following plantar tissue injury in patients with diabetes may influence plantar tissue adaptation and the risk of ulcer recurrence.

Adaptation, Physiological↗

PubMed2001

Monitoring in-shoe plantar pressures, temperature, and humidity: reliability and validity of measures from a portable device.

OBJECTIVE: To investigate the reliability and validity of measures obtained from a portable electronic device used to monitor changes in plantar pressure, temperature, and humidity that occur within the shoe during prolonged activity. DESIGN: Descriptive study comparing electronic sensor output with criterion values. SETTINGS: Indoor level walkway for pressure data; uncontrolled, outdoor environment for step count data; enclosed environmental control chamber for humidity and temperature data. PARTICIPANTS: Convenience sample of 4 healthy, sensate subjects. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Correlations between sensor output and criterion measures were determined for pressure and temperature data. The absolute differences between sensor output and criterion values of temperature, humidity, and step count were also determined. RESULTS: Pressure measurements from electronic sensors correlated highly with criterion values (r > or =.82), both before and after prolonged use. Relative humidity sensor output were within 5% of hygrometer values. In-shoe temperature data correlated highly with criterion values (r > or =.99), and differed from known temperatures by.50 degrees +/-.84 degrees C and.96 degrees +/- 1.56 degrees C at the forefoot and heel, respectively. Electronic step counts recorded at the central forefoot were within 1 step of visual step counts. Pressure tracings obtained from the device during different weight-bearing activities revealed qualitatively distinct pressure patterns. CONCLUSION: The device provides valid and reliable measures of in-shoe plantar pressures, temperature, and humidity during prolonged activity.

Diabetic Foot↗

PubMed2001

In-shoe multisensory data acquisition system.

Patients with diabetes and peripheral neuropathy are susceptible to unnoticed trauma on the foot that can cause skin breakdown. We have designed an electronic system in a shoe that monitors temperature, pressure, and humidity, storing the data in a battery-powered device for later uploading to a host computer for data analysis. The pressure sensors are located at the heel, and under three metatarsal heads. Temperature sensors are located under the medial metatarsal head and under the heel. The humidity sensor is located in the toe of the shoe. Correlations of data from pressure sensors with known values were high (r > 0.85), even after extended use. Although data currently are being collected for descriptive purposes, the design potentially can be used to provide feedback to patients.

Data Display↗

PubMed2000

Use of a classification system to guide nonsurgical management of a patient with chronic low back pain.

BACKGROUND AND PURPOSE: This case report describes the use of a classification system in the evaluation of a patient with chronic low back pain (LBP) and illustrates how this system was used to develop a management program in which the patient was instructed in symptom-reducing strategies for positioning and functional movement. CASE DESCRIPTION: The patient was a 55-year-old woman with a medical diagnosis of lumbar degenerative disk and degenerative joint disease from L2 to S1. Rotation with extension of the lumbar spine was found to be consistently associated with an increase in symptoms during the examination. Instruction was provided to restrict lumbar rotation and extension during performance of daily activities. OUTCOMES: The patient completed 8 physical therapy sessions over a 3-month period. Pretreatment, posttreatment, and 3-month follow-up modified Oswestry Disability Questionnaire scores were 43%, 16%, and 12%, respectively. DISCUSSION: Daily repetition of similar movements and postures may result in preferential movement of the lumbar spine in a specific direction, which then may contribute to the development, persistence, or recurrence of LBP. Research is needed to determine whether patients with LBP would benefit from training in activity modifications that are specific to the symptom-provoking movements and postures of each individual as identified through examination.

Activities of Daily Living↗