Functional assessment in Physical and Rehabilitation Medicine. Assessment of functional impairment and activity limitations. Rehabilitation potential and prognosis. Formulation of short- and long-term rehabilitation goals

01Why assess function: the ICF model

A diagnosis says what the disease is. It does not say what the person can do. Two people with the same stroke can be very different: one walks home in a week, the other needs care for life. Functional assessment in physical and rehabilitation medicine measures what the person can and cannot do, and why, so treatment can be aimed at the gap. As the professor's book puts it, the patient is treated, not the disease.

The framework is the WHO International Classification of Functioning, Disability and Health (ICF, 2001). It sees functioning at three levels, each affected by the health condition and by context:

The arrows between them go both ways. An impairment can limit an activity, but a ramp (environment) can remove the restriction without changing the impairment, and fear of falling (personal) can limit activity with no impairment at all. This is the biopsychosocial view: rehabilitation can work on any box.

In the ICF each problem can be given a qualifier from 0 (no problem) to 4 (complete problem), and short lists of the categories that matter in a condition (ICF core sets) are used in practice. The ICF also separates capacity (what a person can do in a standard setting, such as the gym) from performance (what they actually do at home), which explains why a patient who walks well in therapy may still not walk at home.

02Assessing impairment

The professor's school calls the bedside examination the kinesiologic analysis. It moves from looking (somatoscopy) to measuring (anthropometry, goniometry, muscle testing, gait and ADL analysis).

Somatoscopy

Somatoscopy is the trained visual inspection of the body's build, posture and movement. It is subjective, so it is graded: A normal, B slight deviation, C moderate deviation, D severe deviation.

Static somatoscopy is done standing, barefoot, from the front, back and side:

• From behind and in front: the levels of the ears, shoulders, shoulder blades, iliac crests, gluteal folds and knees; the waist triangles (the spaces between arms and trunk), equal on both sides in a straight spine; the Michaelis rhombus over the sacrum (lumbar dimples), symmetrical when the pelvis is level; a plumb line from the back of the head should fall through the spine and the natal cleft.
• From the side: the plumb line should pass through the ear, shoulder, greater trochanter, just in front of the knee and in front of the ankle. The spine's curves are checked: cervical lordosis, thoracic kyphosis, lumbar lordosis, and their exaggeration or flattening.

Dynamic somatoscopy watches the body moving: forward, backward and side bending and rotation of the spine (looking for stiff or overly mobile segments, a scoliosis rib hump on forward bending), breathing pattern (upper ribs rising, lower ribs widening sideways like a bucket handle, the abdomen moving with the diaphragm) and walking (step length and symmetry, arm swing, trunk rotation, limping, circumduction).

Anthropometry

Anthropometry measures the body: lengths, girths, widths, mass, and indices built from them. In rehabilitation the useful ones are:

• Limb lengths. True leg length from the anterior superior iliac spine to the medial malleolus; apparent length from the umbilicus. A difference in true length is in the bones; a difference only in apparent length comes from a pelvic tilt or contracture.
• Girths (circumferences) measured at a fixed distance from a landmark on both sides: wasting of the thigh after knee injury (for example 10 and 20 cm above the patella), swelling of a limb, oedema monitoring.
• Body mass index and waist circumference.
• Dynamometry: grip strength with a hand dynamometer, a quick, reliable measure that also predicts frailty in older people.
• Vital capacity and spirometry.

The book also gives classic proportion indices (Brugsch and Erisman chest indices, vital capacity indices, Broca's ideal weight). They come from older physical education practice and are rarely used today.

Goniometry

Goniometry measures the range of motion of a joint with a goniometer: a protractor with two arms. The fulcrum is placed over the joint's axis, the fixed arm along the proximal segment, the moving arm along the distal segment.

1. 1

   Start

   Standard position, usually the neutral (anatomical) position as zero; the proximal segment stabilised.
2. 2

   Move

   The patient moves (active range) or the examiner moves the limb (passive range) through the full available range in one plane.
3. 3

   Read

   At the end of the range, at eye level, noting pain and the end-feel.
4. 4

   Record

   Joint, plane, active or passive, the three numbers of the neutral-zero method, the side compared.

The neutral-zero method (SFTR, from sagittal, frontal, transverse, rotation) records each plane with three numbers: the movement away from the body or backward (extension, abduction, external rotation), then the neutral position 0, then the opposite movement (flexion, adduction, internal rotation).

Typical normal ranges, rounded: shoulder flexion 170 to 180 and abduction 180 degrees; elbow flexion about 150; hip flexion about 120 with the knee bent, extension 10 to 20; knee flexion about 135 to 140, extension 0; ankle dorsiflexion about 20, plantar flexion 40 to 50. The side-to-side comparison and the change over time matter more than the textbook value.

Sources of error: wrong landmarks, the fulcrum off the axis, a different starting position each time, reading at an angle, and not stating whether the range was active or passive. For the same examiner, a difference of less than about 5 degrees between measurements is within error; between different examiners the error is larger, so the same person should measure each time. Active range much smaller than passive range points to weakness or pain; both equally small point to a stiff joint or short tissues.

Manual muscle testing

Manual muscle testing (MMT) grades the strength of a muscle or muscle group by what it can do against gravity and the examiner's hand. The patient is positioned so the muscle works either with gravity eliminated (moving in the horizontal plane) or against it, the proximal segment is stabilised, the movement is demonstrated, and resistance is applied gradually and opposite to the movement, near the end of the segment.

Grade 3 is the turning point for therapy. Below it, exercise is done with gravity removed: in the horizontal plane, in suspension slings or in water, or assisted by a therapist. From grade 3 the muscle can work against gravity, and from grade 4 against added resistance. Plus and minus are often added (4+, 4−) to show smaller changes in the upper grades, where MMT is least sensitive: a muscle at grade 5 by hand may still be much weaker than it should be, so a dynamometer (hand-held or isokinetic) measures it better.

Pain, spasticity, fatigue and poor cooperation all distort MMT. In upper motor neuron disease the strength of single muscles matters less than patterns of movement, so stroke assessment uses other tools (Brunnstrom stages, Fugl-Meyer), and spasticity is graded with the modified Ashworth scale (0 to 4).

Other impairment measures

• Pain: a 0 to 10 numerical rating scale or a 100 mm visual analogue scale.
• Sensation, reflexes, coordination and balance (Romberg, Berg Balance Scale): see balance and coordination.
• Gait analysis: by eye, by timed walks, and in the laboratory with force plates, motion capture and electromyography of the walking muscles.
• Cognition, mood and swallowing, which often decide the outcome more than strength does.

03Assessing activity limitations

Activities of daily living (ADL) are the things a person does every day to look after themselves. Basic ADL are self-care and mobility: eating, washing, dressing, toileting, continence, transfers, walking and stairs. Instrumental ADL (IADL) are the more complex tasks of living alone: shopping, cooking, housework, using a phone, managing medicines and money, and using transport.

The FIM's seven levels are the clearest ladder of independence, and the slides use the same ladder:

The Barthel index is quick and free, and a common reading of its total is: 100 independent, 91 to 99 slight dependence, 61 to 90 moderate, 21 to 60 severe, 20 or less total dependence. Its weakness is the ceiling: a patient can score 100 and still be unable to cook, shop or work. The FIM is more sensitive and includes cognition, but takes training.

Timed performance tests measure activity in numbers: the Timed Up and Go, walking speed over 10 metres, the 6-minute walk test for endurance, the 30-second chair stand. Disease-specific questionnaires add the patient's own view: the Oswestry Disability Index for low back pain, WOMAC for hip and knee osteoarthritis, DASH for the arm.

ADL assessment looks at how, not only whether: is it safe, how long it takes, which aid or adaptation is used, how tired it makes the patient, and what help is needed. A home visit often shows what the gym hides.

04Rehabilitation potential and prognosis

Rehabilitation potential is the realistic room for improvement in a patient: how much function they can regain, and how much they can gain from a rehabilitation programme. It is a judgement made by the team after the assessment, and it decides the goals, the setting and the intensity.

It depends on factors that pull up or down:

Prognosis in rehabilitation answers two questions: how much will recover by itself (natural recovery), and what the patient will be able to do with treatment. Recovery can come by three routes:

• Restitution: the damaged function itself comes back (nerve regrowth, a healed fracture, brain plasticity).
• Compensation: other parts take over (using the other hand, the hip strategy for balance).
• Adaptation: the task or the world is changed (a wheelchair, a ramp, a lighter job).

The professor's book links the choice of method to potential: after a central nervous system lesion, methods that aim at near-normal movement (Bobath) are chosen when the potential is good, and methods that use available movement patterns to reach function (Brunnstrom) when it is limited.

Prognosis is helped by known predictors. After stroke, for example, sitting balance and continence in the first days and the Barthel score at the end of the first week predict later independence, and some voluntary finger extension and shoulder abduction within 72 hours predicts that the hand will regain at least some dexterity by six months.

05Short- and long-term rehabilitation goals

Goals turn the assessment into a plan. They are set with the patient and family, by the whole team, around what matters to the patient.

• The long-term goal describes the end of this episode of rehabilitation, weeks to months away, at the level of activity and participation: return home and live alone with a stick; return to office work; walk to the shops.
• Short-term goals are the steps toward it, days to a couple of weeks away, often at the level of impairment and basic activity: knee flexion to 90 degrees in a week; transfers bed to chair with supervision in 10 days.

Each goal is SMART:

"Improve walking" fails every letter. "Walk 50 metres indoors with a rollator without help, within three weeks, so she can get to the bathroom at night" passes them all.

Goal Attainment Scaling turns goals into a score: each goal is written at five levels, from much less than expected (−2) through expected (0) to much better than expected (+2), and the result at review is marked on it.

1. 1

   Assess

   History, ICF-based examination, scales, the patient's wishes.
2. 2

   Judge

   Rehabilitation potential and prognosis; which problems can change.
3. 3

   Set goals

   Long-term goal first, then short-term steps, SMART, agreed with the patient.
4. 4

   Plan and treat

   Choose methods and dose for each goal, assign team members.
5. 5

   Reassess

   Repeat the same measures; meet, adjust, or set new goals.