SCHOOL OF HUMAN KINETICS Biomechanics Research Lab Biomechanics: Past, Present and Future Prof....

SCHOOL OF HUMAN KINETICSBiomechanics Research Lab

Biomechanics: Past, Present and Future

Prof. Mario Lamontagne PhDSchool of Human kinetics

Dept. of Mechanical EngineeringUniversity of OttawaOttawa, On Canada


Introduction

How will patients with deficiencies be treated in the twenty-first century and beyond?

No one can predict the future.

We can have an educated guess If yesIf yes


Ultimate Goal Full restoration of injured

joints to pre-injury status with their complete mechanical and physiological function through genetic manipulation

Evolution of biomechanical methods and rehabilitation treatment from the past, present and near future


Past, Present, and Future

Development or improvement of biomechanical tools

Rehabilitation Treatment

Clinical approaches



Kinematics (Human Motion Analysis) (Past to Present)• Chronophotography to 3D motion

analysis> Chronophotography (markers)> Film camera> Electrogoniometer> Cinefilm camera> Television interfaced to computer> Video Camera> Infrared active markers (opto-electronic

system)


Edward James Muybridge

• Not a biomechanist but a photographer and inventor.

• First known for his nature photographs.

• Literally got away with murder in 1875 when he knocked on the door of his wife’s lover and shot him, admitted to it openly, and was found innocent of the crime by a jury of his peers in San Francisco.

• Most important contribution to kinematics: revolutionized shutter speeds and exposure times.


• Commissioned by Leland Stanford, who later founded Stanford University, to photograph his racehorses.3

• First captured images of a horse running by stringing thread across the track so that hoof strikes triggered the shutters--very jerky.3

• In 1877, John D. Isaacs created electrical triggers for him--smoother and did not jar the cameras.3

• In 1878, he captured the famous sequence of photos that we know today. Used 12 cameras, and invited the press to watch. When they saw the results, the news traveled around the world almost as fast as his shutters fired.3


ETIENNE-JULES MAREY

• French physiologist that was working with high-speed photography at the same time as Muybridge.

• Built on Muybridge’s work and in 1888 he created the “chronophotograph.”

• Rather than using multiple cameras, it captured multiple images with one camera on one photo plate.

• Dramatic impact on modern kinematics as he was the first to use marker sets.

• Had his subjects wear black suits with metallic or white strips and buttons at the joints.


• Continued his work with photography and also invented a slow motion camera that took 700 frames/sec (1894).

• Other notable inventions:

• Sphygmograph--graphically recorded aspects of the pulse and blood pressure (principles still used today).

• Kymograph--shoes with pneumatic soles to record swing and support times during running.

• Pneumatic force platform to record ground reaction forces.

• “Photo gun” that exposed at 1/72 sec to record bird flight--vital in understanding flight.


WILHELM BRAUNE AND OTTO FISCHER

• Most significant work is The Human Gait (Der gang des Menschen).

• Performed an extremely thorough analysis of gait using 4 cameras without shutters and subjects marked with Geissler tubes which emitted current that could then be seen on film.

• Very slow and tedious process, but it yielded the “first available account of joint moments during the swing phase of walking.”

• Their methods are still in use today with very minor changes.


NIKOLAJ BERNSTEIN

•Developed precise kinematic procedures using cyclography, a film camera, and a mirror (1920s-30s).8

•Moved film slowly through the camera--kymocyclography.8

•Used a mirror placed at a 45 degree angle to the optical axis of one camera, therefore each picture would include a frontal and lateral view of the subject.8

•Eliminated problem of synchronizing two cameras for measuring in 3D.8


THE BERKELY GROUP

• Group working out of Biomechanics Laboratory at UC Berkely in the 1940s led by Saunders, Inmann, and Sutherland.8

• Working with prosthetics for soldiers who lost limbs in World War II.8

• Used a simpler method for kinematic measurement than their predecessors--set up three cameras: lateral, frontal, and transversal from above.8

• Inserted pins into volunteer subjects’ femurs and tibias--this method was highly criticized, but it did yield some important findings.8


THE BERKELY GROUP• The research “produced six so-called kinematic

determinants of normal gait which, in summary, determine the trajectory of the center of gravity of the body during gait.”

• Compass gait--initial state--only flexion/extension at the hip

• 1st determinant--pelvic rotation

• 2nd determinant--pelvic tilt

• 3rd determinant--knee flexion in the stance leg

• 4th and 5th--encompass foot and knee mechanisms

• 6th--lateral displacement of pelvis


HAROLD EDGERTON

• Made stroboscopic pictures famous in the 1960s by recording golf swing, springboard diving, and impact of golf and tennis balls.9

• Uses an open shutter to capture multiple images on one negative--number of positions recorded is determined by the frequency of the flashing light.9

• Useful in capturing impact on film because strobe can be synchronized with sound, etc., but limited in recording body motion because of overlapping images when the subject stays in one place.9

• Used all the way through the 1970s, but very limited practical use for obtaining kinematic data.9


MODERN TECHNIQUES

High-Speed Photography

• dominant until 1970s, and still used often for studying locomotion in sports because it is non-invasive

• typically 3-4 cameras are synchronized (although in theory only 2 are required) and shoot at 50-100 frames per second

• Not as practical because of the delay in processing film--corrections cannot be made (if needed) while trials are taking place


MODERN TECHNIQUES

Optoelectronic systems

• Systems that use Passive Markers

• Includes video-kinematic systems such as MA, VICON, and ELITE.

• Markers are usually circular, disc-shaped, or spherical and covered in reflective tape--cameras emit light and markers reflect it.

• MA and VICON were the first devices made available for commercial use.

SCHOOL OF HUMAN KINETICSBiomechanics Research Lab 10



Kinematics (Human Motion Analysis) (Present to Future)• Improvement (to be done)

> Skin artifacts> Integrated movement analysis

(3D)> Model Validation

Gaio Lakin 1 and Michael Schwartz 2,3Gaio Lakin 1 and Michael Schwartz 2,3

1 Children’s Health System, Birmingham, AL 2 Gillette Children’s 1 Children’s Health System, Birmingham, AL 2 Gillette Children’s Specialty Healthcare, St. Paul, MN 3 University of Minnesota, Specialty Healthcare, St. Paul, MN 3 University of Minnesota,

Minneapolis, MNMinneapolis, MN

±2°±2°

±3°±3°

±5°±5°

±8°±8°



Kinematics (Human Motion Analysis) (Present to Future)• Development (to be

done)> Integrated and

personalised motion analysis– Kinematics,

Kinetics, neuromuscular system, and other system such as MRI



Kinematics (Human Motion Analysis) (Present to Future)Development (to be improved)

Biomechanical Measurements over long durationelectromagnetic tracking deviceGRF stored in a data logger

(Whalen RT et al. ASME Advances in Bioengineering 26, pp. 535-538, 1993).


Rehabilitation Treatments

Surgical Treatments (up to now)• Development of autografting

techniques that are less damaging then the past techniques.

• Better fixation techniques of the allografts (All Inside Technique).

• Computer-assisted surgery for the graft position

• Robotic surgery


Rehabilitation Treatments

Non-Surgical Treatment (near future)• Manipulation of the local

physiologic environment with additives such as various tissue growth factors including nerve growth factors, to induce more normal restoration of microanatomy and neurologic components.


Clinical approaches

Isolated approach towards Integrated approach• Up to now, rehabilitation

approach is injury specific and profession specific

• In the near future, an integrated approach should be developed as proposed

• In the future, the mutltilayer feed-forward neural network can be developed to identify the ultimate clinical approach.

New Integrated Approach to Orthopedics Rehabilitation Problems

Sport Medicine,Orthopedic andPhysiatrist

Biomedical andBiomechanical

Engineering

PhysiotherapyandAthletic Therapy

Epidemiology

Population-based monitoringRisk Factor identificationIntervention Evaluation

DiagnosticInterventionRehab. Rx

Clinical EvaluationRehab ProgramFollow-up

Research on Rehab ProgramResearch on InterventionNew Tools

Better PatientManagement


Conclusions

Even after reaching the level of excellence in biomechanical knowledge, surgical procedures, and rehabilitation modalities, the real challenge will consist of integrating all concepts in order to fully reinstate the human performance.

All pieces of information should enter a multilayer feed-forward neural network to select the ultimate rehabilitation approach.

SCHOOL OF HUMAN KINETICS Biomechanics Research Lab Biomechanics: Past, Present and Future Prof....

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