NPTAE

This chapter covers the measurements PTAs collect every day under the PT's plan of care: goniometry, manual muscle testing, end feels, capsular patterns, girth, limb length, palpation, posture and movement observation, and awareness of special tests. Data collection is within PTA scope; interpreting the data to make a diagnosis or to change the plan is the PT's role.

Standard goniometer alignment places the axis (fulcrum) over the joint's center of rotation, the stationary arm along the proximal segment, and the moving arm along the distal segment. Stabilize the proximal segment to stop substitution, use a consistent starting position, and record the starting and ending positions in degrees. A normal elbow is recorded as 0-150 deg; an elbow that lacks 15 deg of extension and flexes to 130 deg is recorded as 15-130 deg.

MMT grades strength on a 0-5 scale. Test against gravity first; only if the patient cannot complete the range against gravity do you place them in a gravity-eliminated (gravity-minimized) position. Apply resistance at the distal end of the segment being moved, perpendicular to the limb, after the patient reaches the test position (break test), and stabilize proximally.

The 3/5 line is the most important threshold. A muscle graded 3 can lift the part against gravity but cannot handle added load; exercise begins with gravity-resisted active ROM, not heavy weights. A muscle graded 2 starts with gravity-eliminated or active-assisted work. A muscle graded 1 needs facilitation, NMES or biofeedback per the POC, and active-assisted movement.

End feel is the quality of resistance at the end of passive range. Normal end feels are bony or hard (elbow extension, olecranon into fossa), soft tissue approximation (knee or elbow flexion, muscle bulk meeting), and firm or capsular (shoulder ER, hip IR, stretch of capsule and ligaments). Abnormal end feels include an empty end feel (patient stops motion because of pain before any mechanical resistance is felt: suggests acute bursitis, fracture, tumor or severe inflammation), springy block (rebound from an internal derangement such as a torn meniscus), muscle spasm (sudden guarded stop), and a bony end feel where it does not belong (osteophytes).

When the whole joint capsule is involved (arthritis, adhesive capsulitis, prolonged immobilization), motion is limited in a predictable order called the capsular pattern. Noncapsular limitation (one motion only) points to a ligament, a loose body or an extra-articular lesion.

Girth (circumference) measurements document edema and muscle atrophy. Use bony landmarks and fixed intervals, for example the knee joint line and 5, 10 and 15 cm above and below it. Keep the patient's position, tape tension and landmarks identical each time, and measure both sides. Measure atrophy farther from the joint (for example 10-15 cm above the patella over the quadriceps), and measure effusion at the joint line.

True (structural) limb length is measured from the anterior superior iliac spine (ASIS) to the medial malleolus. Apparent (functional) limb length is measured from the umbilicus to the medial malleolus. A difference in apparent length with equal true length suggests pelvic obliquity, a hip adduction or abduction contracture, or scoliosis rather than a bone-length difference.

Common landmarks used for goniometry, girth and posture: acromion, greater tubercle of the humerus, lateral and medial epicondyles, olecranon, radial and ulnar styloid processes, iliac crests (the level of L4-L5), ASIS, PSIS (the level of S2), greater trochanter, femoral condyles, tibial tuberosity, fibular head (where the common fibular nerve wraps and can be compressed), malleoli, navicular tuberosity and the base of the fifth metatarsal.

PTAs should recognize common special tests, know what each is designed to detect, and be able to collect the data when it is part of the POC and allowed by state law and facility policy. Interpreting a special test to establish or change a diagnosis is the PT's job. On the exam, a PTA who discovers a new positive finding reports it to the PT; the PTA does not label the diagnosis or change treatment based on it.

Observing gait, transfers, squatting, reaching and stair climbing lets the PTA spot faulty mechanics and report progress objectively. Describe what you see in measurable language: "Patient demonstrates contralateral pelvic drop of about 5 deg during right single-limb stance, 10 of 10 steps" is useful; "patient walks poorly" is not. Gait deviations with assistive devices, orthoses and prostheses are covered in Section 10; tie each deviation back to a weak or tight structure when reasoning through an item.

• Goniometer axis on the joint center, stationary arm on the proximal segment, moving arm on the distal segment; stabilize the proximal segment.
• MMT grade 3 means full range against gravity; grade 2 means full range with gravity eliminated; do not use MMT for spastic muscles.
• Empty end feel and springy block are abnormal findings to document and report to the PT.
• Capsular patterns: shoulder ER > abduction > IR; hip IR most limited; knee flexion > extension.
• True limb length runs ASIS to medial malleolus; apparent runs umbilicus to medial malleolus.
• The PTA can collect special-test data within the POC, but the PT interprets it and changes the plan.