16.2 Postural Stability, Dynamic Balance, Body Mechanics & Breathing
Key Takeaways
- Domain 3 Task 3 requires techniques for promoting improved postural stability, dynamic balance, body mechanics, and breathing patterns during functional tasks.
- Postural control draws on somatosensory, visual, and vestibular input; on a firm surface in good light, somatosensory input dominates, which is why a dark hallway with a plush rug removes two systems at once.
- Balance recovery follows a strategy hierarchy: ankle strategy for small slow perturbations, hip strategy for larger or faster ones, and stepping strategy when the center of mass leaves the base of support.
- Widely used fall-risk cutoffs include a Berg Balance Scale score under 45, a Timed Up and Go of roughly 12 seconds or more in community-dwelling older adults, and Functional Reach under about 6 inches.
- Pursed-lip breathing is the intervention for obstructive lung disease: inhale through the nose, exhale through pursed lips roughly twice as long, which maintains back pressure and prevents airway collapse and air trapping.
Postural Stability, Dynamic Balance, Body Mechanics & Breathing
The blueprint's third knowledge statement under Domain 3, Task 3 covers techniques for promoting improved postural stability, dynamic balance, body mechanics, and breathing patterns during functional tasks. Every word of that statement ends in during functional tasks — this is not a gym program, it is what allows a client to stand at a sink, reach into a cabinet, and carry a laundry basket.
1. The Sensory Basis of Postural Control
Three systems feed postural control, and their relative weighting shifts with conditions:
| System | Contribution | When It Dominates |
|---|---|---|
| Somatosensory (proprioception, cutaneous pressure) | Fastest and most heavily weighted in ordinary conditions | Firm, level surface with adequate light |
| Visual | Provides reference to the environment | Compliant or unstable surface; unfamiliar setting |
| Vestibular | Resolves conflict between the other two | When both surface and visual information are unreliable |
The clinical consequence: an older adult with peripheral neuropathy already has degraded somatosensory input and is compensating with vision. Put that person in a dark hallway on a plush rug at 2:00 a.m. and you have removed both remaining systems. This is why night lighting and rug removal are not trivial recommendations — they are sensory-system interventions.
Postural Control Categories
- Steady-state (static): maintaining a position — sitting unsupported, standing at the sink.
- Anticipatory (feedforward): postural adjustments made before a voluntary movement — the trunk pre-activates before you lift a heavy pan.
- Reactive: recovery after an unexpected perturbation — a bump in a crowded store, a dog pulling the leash.
A client who is stable standing still but falls when reaching into a high cabinet has an anticipatory deficit. A client who cannot recover from a nudge has a reactive deficit. They require different training.
The Strategy Hierarchy
| Strategy | Triggered By | Movement |
|---|---|---|
| Ankle | Small, slow perturbation on a firm surface | Body sways as a rigid unit about the ankles |
| Hip | Larger or faster perturbation, or a narrow or compliant surface | Rapid hip flexion or extension with counter-rotation |
| Stepping | Center of mass exceeds the base of support | A step or a reach-to-grasp to establish a new base |
2. Assessing Balance
| Measure | Structure | Common Fall-Risk Threshold |
|---|---|---|
| Berg Balance Scale | 14 items, 0–4 each, maximum 56 | Score under 45 indicates significant fall risk |
| Timed Up and Go | Rise from a chair, walk 3 meters, turn, return, sit | Roughly 12 seconds or more in community-dwelling older adults indicates increased risk |
| Functional Reach Test | Maximum forward reach in standing without stepping | Under about 6 inches indicates high fall risk |
| 30-Second Chair Stand | Number of sit-to-stands in 30 seconds | Below age- and sex-normed values indicates lower-extremity weakness |
| 4-Stage Balance Test | Progressive narrowing stance to tandem and single-leg | Inability to hold tandem stance 10 seconds indicates risk |
| Dynamic Gait Index / Functional Gait Assessment | Gait with head turns, obstacles, speed change | Identifies dynamic and vestibular contributions |
Occupational therapists also assess sitting balance — static and dynamic, supported and unsupported — because it governs dressing, bathing, and self-feeding long before standing balance matters.
3. Training Balance Inside Occupation
- Task-specific practice beats generic exercise. Reaching for cereal from a real cabinet trains the exact anticipatory adjustment the client needs; standing on a foam pad does not transfer as reliably.
- Grade systematically: widen to narrow base of support; supported to unsupported; static to dynamic; firm to compliant surface; eyes open to eyes averted (scanning a shelf); single task to dual task (carrying a full cup while conversing).
- Reach beyond the base of support progressively — forward, lateral, across midline, overhead, and to the floor — since floor-level retrieval is where many real falls occur.
- Perturbation and step training builds reactive control: controlled nudges with guarding, then step-recovery practice.
- Dual-task training matters because real falls happen while doing something else. A client who stops walking to answer a question is at elevated risk.
- Floor-recovery training — teaching a client how to get up from the floor — reduces the "long lie" that turns a fall into a hospitalization.
- Evidence-based group programs to which occupational therapists refer or contribute include the Otago Exercise Programme, Tai Chi, A Matter of Balance (which targets fear of falling), and Stepping On.
4. Body Mechanics for the Client
Distinct from the practitioner's body mechanics, this is client education for back protection and efficient movement:
- Hip hinge, not spine flexion. Bend at the hips and knees; keep the spine neutral.
- Load close to the body. Every inch farther from the trunk multiplies spinal compression.
- Never twist under load. Turn the feet.
- Push or slide rather than lift. Use wheeled carts, sliding surfaces, and gravity.
- Split the load. Two light trips beat one heavy trip; two bags balanced beat one on one side.
- Raise the work surface. Gardening at a raised bed, laundry on a table, cooking at counter height.
- Change position every 20 to 30 minutes. Static loading is as damaging as heavy loading.
- Post-lumbar-fusion clients get an explicit no bending, lifting, or twisting rule, log-rolling technique, and a reacher and sock aid to make it achievable.
5. Breathing Patterns During Functional Tasks
Pursed-Lip Breathing — for Obstructive Disease
Inhale through the nose for a count of about two; exhale gently through pursed lips for about twice as long. The back pressure created at the lips splints the small airways open, preventing the dynamic airway collapse and air trapping that define obstructive disease. It reduces respiratory rate, increases tidal volume, and gives the client a controllable response to panic-inducing dyspnea.
Diaphragmatic Breathing
Hand on the abdomen; the abdomen rises on inhalation while the upper chest stays quiet. Reduces accessory muscle use and the energy cost of breathing. It is more difficult in severe hyperinflation and should be introduced when the client is calm, not mid-episode.
Paced Breathing With Activity
The rule clients remember: exhale on the effort. Exhale while standing up, while lifting, while pushing. Pair the breath to the movement, and never hold the breath — a breath hold is a Valsalva maneuver, which spikes intrathoracic pressure and blood pressure and drops venous return.
Positions of Relief
For acute dyspnea, teach forward-leaning postures with the arms supported — leaning on a counter, elbows on knees while seated, or the classic tripod position. Forward lean with arm support fixes the shoulder girdle so the accessory muscles can act on the ribcage, and it mechanically favors the diaphragm.
Energy Conservation for Dyspnea
Sit for grooming and showering; use a shower chair and a long-handled sponge; organize supplies to eliminate trips; use a wheeled cart; break tasks into segments with planned rests; avoid bending at the waist, which compresses the diaphragm; avoid overhead sustained work, which is disproportionately demanding.
6. Grading Activity by Metabolic Cost
Metabolic equivalents (METs) express the oxygen cost of an activity as a multiple of resting metabolism (1 MET is about 3.5 mL of oxygen per kilogram per minute). They allow occupational therapists to match activity to prescribed cardiac or pulmonary limits.
| Approximate MET Level | Representative Occupations |
|---|---|
| 1–2 | Eating, seated grooming, hand sewing, seated conversation |
| 2–3 | Dressing, showering seated, light housework, walking slowly on level ground |
| 3–4 | Standing shower, making a bed, light gardening, sweeping, sexual activity (commonly estimated in the 3–5 range) |
| 4–5 | Stair climbing, vacuuming, raking, carrying groceries |
| 5+ | Heavy yard work, shoveling, brisk walking uphill |
Cardiac rehabilitation phases follow this ladder: Phase I is inpatient, low-level self-care activity; Phase II is monitored outpatient exercise; Phase III is supervised community exercise; Phase IV is independent maintenance. Sternal precautions govern upper extremity activity during the early phases.
Monitoring during activity: use the modified Borg dyspnea scale (0 to 10) alongside oxygen saturation and the talk test — a client who cannot speak a short sentence has exceeded a sustainable intensity.
An occupational therapist is treating a client with severe chronic obstructive pulmonary disease who becomes acutely short of breath while standing at the bathroom sink. Which combination of techniques should the therapist teach FIRST?
A community-dwelling client scores 41 on the Berg Balance Scale, completes the Timed Up and Go in 15 seconds, and reports two near-falls while carrying laundry and talking to a spouse. Which intervention BEST targets the specific deficit this pattern describes?
An occupational therapist is planning an ADL session for a client on postoperative day four following a coronary artery bypass graft, with an activity limit prescribed at approximately 3 METs and full sternal precautions in place. Which activity is MOST appropriate?