Document Type


Date of Award

Spring 5-31-2010

Degree Name

Master of Science in Biomedical Engineering - (M.S.)


Biomedical Engineering

First Advisor

Hans Raj Chaudhry

Second Advisor

Sunil Saigal

Third Advisor

William C. Van Buskirk

Fourth Advisor

Thomas W. Findley


The existing Anatomical Torsion Monitor (ATM) to evaluate mechanical stiffness and viscoelasticity of the low back suffers from various inherent defects. This has to be replaced by an improved device. Also the existing ATM cannot provide oscillations to the low back.

The main objective is to automate the existing ATM for evaluating the low back immediately using objective methods. The specific objective is to provide oscillations for improving the low back dysfunction.

The laser platform and the target chart for recording the readings are dispensed with the existing ATM. Instead, the ultrasound transducers are attached to the pads to record the readings for loading and unloading the low back. The voltage readings are directly recorded in the computer through a DAQ card and the Hysteresis Loop Areas (HLAs) are evaluated using MATLAB. In addition to automation of the ATM for evaluating the lows back, a technique is developed for improving the low back dysfunction by imparting oscillations to the low back. These oscillations can be delivered to the subject using a cam mechanism and a DC motor fitted to the automated ATM (A- ATM). The cam mechanism is used with pneumatic cylinders in order to give the oscillation alternately to both contact pads. The frequency of the oscillations can be controlled by using a speed controller switch.

Ten control subjects (nine males and one female) in the age group of (24-77) were given oscillations to the low back for five minutes duration. HLAs were evaluated before and after the treatment in the form of oscillations. The frequency for each oscillation was 20 cycles per minute with amplitude of 2 inches. The percentage change in HLA as well as Range of motion were obtained and summarized.

The existing ATM is successfully automated which results in objectively evaluating the passive low back and obtaining the results quicker compared to unautomated ATM. The automated ATM can also deliver quantifiable oscillations to the passive low back.

It is observed that providing oscillations to the low back results in improved viscoelasticity of the low back for those subjects whose BMI is 25 or less and an insignificant change in range of motion for all the subjects. It is further observed that based on our tests, the optimal duration of oscillations is 5 minutes. However, the correct displacement amplitude, frequency, and duration of treatment will have to be determined from individual medical and physical conditions.



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