Muscular weakness, proprioceptive deficits, and range of motion deficits may challenge a persons ability to maintain their center of gravity (COG) ›

Regaining Postural Stability and Balance

Rehabilitation Techniques for Sports Medicine and Athletic

Training William E. Prentice

Introduction

Muscular weakness, proprioceptive deficits, and range of motion deficits may challenge a persons ability to maintain their center of gravity (COG)› May lead to loss of balance

Balance is the single most important element dictating movement strategies

Dynamic process involving multiple neurological pathways

Introduction

Joint position sense , proprioception, and kinesthesia are vital to all athletic performance requiring balance

Ability to balance and maintain postural stability is essential to an athlete who is acquiring or reacquiring complex motor skills

Postural control system

Complex process involving sensory and motor components

Most daily activities such as, walking, climbing stairs, throwing a ball, require static foot placement with controlled balance shifts

Balance should be considered both a static and dynamic process

Postural control system

Impaired balance is a result of one or a combination of two reasons

› Position of COG relative to base of support is not accurately sensed

› Automatic movements required to bring COG to a balanced position are not timely or effectively coordinated

Postural control system

Position of the body in relation to gravity and its surroundings is sensed by combining visual, vestibular and somatosensory (proprioceptive)inputs

Balanced movements also involve motions of the ankle, knee, and hip joints› Primary mechanisms for controlling balance occur

in joints of the lower extremity Postural control system operates as a

feedback control circuit between brain and the musculoskeletal system

Somatosensory input

Mechanoreceptors transmit messages to brain through sensory nerves in spinal cord› Helps to control proprioception or

body/joint position

Provides information concerning the orientation of body parts to one another and to the support surface

Balance & Closed Kinetic Chain

Balance is the process of maintaining the COG within the body's base of support

Within kinetic chain each moving segment transmits forces to every other segment along chain› Maintaining equilibrium or balance is associated

with injuries along the closed kinetic chain Injuries to any one of the joints or corresponding

muscles along kinetic chain can result in loss of appropriate feedback for maintaining balance

Control of Balance

Human body is a tall structure on a relatively small base› COG is quite high, just above pelvis

Somatosensory input is preferred sense for balance› i.e. : feet in contact with support surface

and detection of joint movement

Control of Balance

Visual input› Measures orientation of the eyes and head in

relation to surrounding objects› If eyes are closed balance becomes more

difficult Vestibular input

› Sensory system that is leading contributor to response to movement and sense of balance

› Sends signals, primarily to neural structures that control our eye movement, and to muscles that keep us upright

Proprioception & Kinesthesia

Proprioception: ability to determine the position of a joint in space

Kinesthesia: ability to detect movement› Mediated by mechanoreceptors found in

muscle and joints and by cutaneous, visual and vestibular input

Proprioception & Kinesthesia

Joint mechanoreceptors› Found in ligaments, capsules, menisci,

labra and fat pads Sensitive to change in shape of joint

structures and rate and direction of movement of joint

Most active at end ranges of motion

Proprioception & Kinesthesia

Muscle mechanoreceptors› Found in muscles and tendons

Muscle spindles and Golgi Tendon Organs Muscle spindles sensitive to changes in length of muscle

Golgi tendon organs sensitive to changes in tension

Assessment of Balance

Subjective Assessments: Romberg's & Balance Error Scoring System (BESS)

Romberg's test› Feet together, arms out to side, and eyes

closed› Positive test: sway or fall to one side› indicates loss of proprioception

Assessment of Balance Balance Error Scoring System (BESS)

› 3 stances: double , single, and tandem Completed 2 x each: Once on firm

surface and once on unstable surface (Foam pad)

Total of 6 trials Hands on iliac crest and eyes closed

In SL ex. Non stance leg held at 20-30 degrees hip flexion and 40 to 50 degrees of knee flexion

Assessment of Balance

BESS Assessment Continued

20 second test begins when eyes close

Single leg stance on non-dominant leg (NDL) and NDL is in the rear for tandem stance

Upon losing balance athlete returns to testing position as quickly as possible

Assessment of Balance

Balance Error Scoring System (BESS)› Scoring

1 point added for each error that occurs Hands lifted off iliac crest Opening eyes Step, stumble or fall Moving hip into > 30 degrees of flexion or

Abduction Lifting forefoot or heel Remaining out of testing position >5 seconds

Higher scores represent poor balance

Assessment of Balance

Dynamic balance test include functional reach test, timed agility, figure 8’s, carioca, or hop test› Ability to maintain upright posture while

moving

Assessment of Balance

Advancements in technology have provided equipment to quantitatively assess and train dynamic balance› Mostly computer -interfaced force- plate

technology› Potential to assess possible

abnormalities that might be associated with injury and help create appropriate training programs

Injury & Balance

Stretched or damaged ligaments may fail to provide adequate neural feedback› May contribute to decreased

proprioceptive mechanisms, and thus decreased balance

› Increased postural sway and balance instability contributed to neurological factors and biomechanical factors after injury

Balance Training

Rehab program, especially for lower extremities must include exercises to improve balance and postural equilibrium› Any injury can cause disruption at some

point between COG and base of support› If neglected can lead to reinjury, decreased

performance, or other injuries

Balance Training

5 general rules› Safe, yet challenging› Stress multiple planes of motion› Incorporate multisensory approach› Begin with static, bilateral stable surface

and progress to dynamic, unilateral, and unstable surface

› Progress toward sport specific activity

Balance Training

Balance Exercises› Static: COG maintained over fixed base of

support while on stable surface

› Semi-dynamic: Maintain COG over fixed base on moving

support or unstable surface Person transfers their COG over a fixed base

of support on stable surface through range and/or directions

Balance Training

Balance Exercises› Dynamic: maintenance of COG over

moving base of support Usually stable surface, but could be unstable Base of support always changing position so

COG is forced adjust with each movement

› Functional Same as dynamic, but add sport specific

tasks

Balance Training

Phase I› Can be initiated once athlete can bear

weight on the extremity› Static, non ballistic exercise› Hard firm surface› Bilateral to unilateral (double leg to single

leg)› Eyes opened to eyes closed› Progress to unstable surface, perturbations

(taps or movement) Overload or stress somatosensory system

Balance Training Phase II

› Transition of static to semi-dynamic & dynamic ex. Important for running, jumping, and cutting

athletes Progress only if sufficient healing has occurred and

ROM, muscle strength and endurance is adequate Balance through movement

Controlled hip and knee flexion and smooth return to stabilization position

Progress to added resistance and more difficult movement patterns

Balance Training Phase III

› Dynamic & Functional exercises Slow speed to fast speed Low force to high force Controlled to uncontrolled activities

› Jumping or hopping activities Bilateral to unilateral Single plane to multi-plane Exercises may differ between athletes

Be sport specific

Conclusion

Balance and postural stability critical to athletic performance and injury prevention

A rehabilitation program must include functional exercises that incorporate balance and proprioceptive training › Prepare athlete for return to activity› Failure address balance problems may

predispose athlete to reinjury and injury› Use imagination, be creative› Use sport specific tasks