Biomechanical Approach to Treatment:
Maintaining or Preventing Limitation
in Range of Motion
• An individual’s actual ROM at any joint is determined by the
physical constitution of the body and the person’s typical
occupations.
• Functional ROM is the range necessary to perform daily
occupations.
• Occupational therapists are concerned with preventing ROM
limitations that interfere with daily occupations.
Immobilization Reduces Range of
Motion
• When a joint remains immobilized, changes in the muscle
through loss of muscle fiber and change in the number and other
structures result in shortening of the muscle itself.
• With immobilization, muscle filaments lose their ability to slide,
which is necessary for contraction.
• Prolonged swelling can also lead to fibrotic changes and
adhesions in tissue that result in contractures.
• Maintaining ROM can prevent discomfort, skin breakdown,
hygiene problems, and difficulty in caring for the person.
Compression
• Used to prevent ROM limitations secondary to
edema
• The occupational therapist must take care to apply
compression garments correctly so they do not
constrict circulation in the more distal part of the
extremity.
Positioning
• Positioning is essential to avoid development of the following:
–
Deformities
–
edema
–
limitation ROM
• Positions that are opposite of normal patterns of tightness should be encouraged
for at least periods of the day.
• Sometimes contractures and consequent ankylosis are unavoidable because of
the disease process. Positioning, splinting, and bracing are used to ensure that
ankylosis occurs in a functional position if possible.
• When positioning a patient, the occupational therapist must be serious in
anticipating eventual outcomes of prolonged immobilization that may
compromise occupational performance.
Movement Through Full Range of
Motion
• Methods for ranging
–
Teaching the patient to move the joints that are injured, immobilized, or
edematous.
–
Passively move the joints if the patient cannot move.
• AROM and PROM should occur twice daily, moving each involved joint slowly
and gently three times from one limit to the other.
• With PROM, attention must be given to planes of motion and joint
biomechanics.
• AROM is preferred to PROM for reduction of edema because the contraction of
the muscles helps pump the fluid out of the extremity.
• Occupational therapists often structure activities to provide AROM to prevent
limitations in ROM.
Increasing Range of Motion
• If limitations in ROM impair a patient’s ability to function independently in
occupations or lead to deformity, treatment to increase ROM is indicated.
• Problems that can be changed:
–
Contractures of soft tissue
• Skin
• Muscles
• Tendons
• Ligaments
• Problems that cannot be changed:
–
Ankylosis
–
Long-standing contractures
–
Severe joint destruction
Stretching
• Stretch is a process by which tissue is lengthened by an external
force, usually to eliminate tightness that has the potential to
cause a contracture.
• Change is only created when tissue is stretched to the point of
maximal stretch.
• Tight muscles can be stretched more vigorously than tight joints.
• The direction of stretch is exactly opposite to the tightness.
• Residual pain after stretching indicates that the stretch was too
forceful and caused tearing of soft tissues or blood vessels.
Active Stretching
• The use of occupation for
stretching is empirically based
on the idea that a person
involved in an interesting and
purposeful activity will gain
greater range.
• Because occupations can be
performed using a number of
muscle patterns, the therapist
must determine how the patient
completed the activity prior to
injury.
Active Stretching (Continued)
• Occupations used as a means to increase ROM must provide a
gentle active stretch by use of slow, repetitive isotonic
contractions of the muscle opposite the contracture or by use of a
prolonged passive stretched position of the contracted tissue.
• Exercises that increase the range of shortened tissue are the
proprioceptive neuromuscular facilitation (PNF) techniques
called contract-relax and agonist contraction.
Passive Stretching
• Performed prior to engagement in occupation
• Techniques
– Manual stretch
– Use of orthotic devices
• Splints
• Casts
Biomechanical Approach to Treatment:
Strengthening
• If limitations in a patient’s strength prevent participation in occupations,
treatment aimed at increasing strength is warranted.
• If weakness prohibits patients from moving the limb or maintaining a functional
position, their lack of regular active range of motion will lead to contracture.
• Occupation or exercise parameters that may be manipulated to increase strength
include the following:
–
Type of contraction
–
Intensity or load
–
Duration of contraction
–
Rate or velocity of contraction
–
Frequency of exercise
Occupations and Exercise
• Therapists may find that various occupations provide sufficient
opportunities for muscle strengthening and are more effective at
maintaining the patient’s interest and motivation than exercise
alone.
• Exercise may be used as a warm-up to occupation, or occupation
may be introduced to enhance the strength gained by exercise.
Grading Muscle Strength Parameters
• When prescribing a strengthening program, therapists can
manipulate the exercise or occupational parameters.
• Progressive Resistive Exercise
• Simplified Strengthening Program
Grading Muscle Strength Parameters
(Continued)
• The type of contraction is established by the demands of the task
and assistance provided by the therapist.
–
Concentric
–
Eccentric
–
Isometric
• The type of contraction should mirror what is required by the patient’s occupations
because transfer of training across contraction types is unlikely.
• Intensity or resistance should be increased over time for strengthening.
• Resistance can be graded by adding a load to the extremity or by changing the plane
of movement.
• The rate or velocity of contraction, described as the number of repetitions per period
of time, must be gradually increased according to the patient’s abilities and comfort.
Biomechanical Approach to Treatment:
Increasing Endurance
• Less than maximal resistance over time
– Doing repetitive concentric or eccentric contractions against
less than maximal resistance increases endurance through
less glycogen depletion and improved oxidative capacity of
muscle fibers.
– Exercise to increase muscle endurance therefore uses
moderately fatiguing activity for increasingly long periods
with intervals of rest to allow metabolic recovery.
Biomechanical Approach to Treatment:
Increasing Endurance
• Grading Occupations to Increase
Endurance
–
Occupation or exercise used to
build muscular endurance is
graded by increasing the exercise
period, which is done either by
raising the number of repetitions
of a contraction or by
lengthening the time an isometric
contraction is held.
– If patients are not ready to increase duration times,
they can increase the frequency of engaging in
occupation or exercise.
– Occupational therapists can work with patients to
schedule their everyday routines so that they
gradually increase the amount of time they engage in
occupations throughout the day.
Nancy A. Flinn, Jeanne Jackson, Julie McLaughlin Gray, and Ruth Zemke, Occupational Therapy for Physical Dysfunction, Sixth Edition
©2008 LWW