Page 108 - Canine Lameness

80 5 The Rehabilitation Examination

normal end‐feel should be “tissue approximation”; Table 5.1 and Figure 5.2) and the tester can
palpate and see muscle spasms during testing. In this instance, because the supraspinatus is a sin-
gle‐joint muscle, the PROM position and the stretched position are the same; the tester would
further evaluate the muscle for pathology by direct palpation (Chapter 6).
In the third instance, if PROM is excessive with an elastic or muscle spasm end‐feel, flexibility
testing is completed to determine which muscles are injured. For example, when tarsal hyperflex-
ion is observed, flexibility testing of the tarsal extensor muscles (e.g. gastrocnemius) should be
completed to determine which muscles may be contributing to the excessive PROM and to what
extent they are injured as described in the first instance above.

5.4.1 How to Perform Flexibility Testing
To test flexibility of a specific muscle, the patient should be placed in lateral recumbency and
relaxed. The observer needs to be familiar with the origin (the most proximal aspect) of the muscle
as well as the insertion (the most distal aspect) of the muscle. The observer then manually stabilizes
the bone on which the origin of the muscle is located and slowly guides the insertion of the muscle
away from the origin placing the muscle on a passive stretch (i.e. performing the opposite joint
motion as a concentric contraction would elicit; Figure 5.4). While holding the stretch, the observer
notes the amount of flexibility (in comparison to the contralateral side), the patient’s response to
flexibility (e.g. pain and pulling away), and the body’s response to flexibility (e.g. muscle spasms).
While goniometric normal values have been described for PROM testing, such values have not
been described for flexibility testing in dogs. To use goniometric measurements for flexibility test-
ing, the joint angle of the muscle origin must remain static while the tester is measuring the inser-
tion joint angle. For example, when measuring flexibility of the gastrocnemius muscle with a
goniometer, the joint angle of the stifle must remain consistent during the test, as well as from one
test to another (e.g. maintaining that the stifle is positioned and held at 140° while tarsal flexion is
measured each time). Because goniometric measurements of muscle flexibility have not been eval-
uated in the canine model, in clinical practice, the degree of flexibility is most commonly com-
pared to the other limb.

5.4.2 How to Interpret Flexibility Testing
Flexibility testing is completed to determine if a muscle is contributing to lameness and if so, to what
extent the muscle may be injured. A minor muscle injury may have associated normal to mildly
decreased flexibility with pain and muscle spasm. For instance, in the earlier example of acute teno-
synovitis of the biceps brachii muscle, PROM of shoulder flexion may be normal, but flexibility of the
biceps brachii is decreased and painful. In comparison, a moderate muscle injury may produce
increased flexibility due to fiber disruption with associated pain and muscle spasm. An example is
lameness due to a partial biceps brachii rupture for which PROM of shoulder flexion may be normal,
but flexibility of the biceps brachii is excessive with pain and muscle spasms. Flexibility testing after
a severe muscle injury may result in extreme flexibility without pain due to absent of intact muscle
fibers. For example, PROM of shoulder flexion due to a complete biceps brachii rupture may be nor-
mal, but flexibility of the biceps brachii is grossly excessive and pain free. Findings such as these from
flexibility testing can be used to determine specifically which muscle and to what extent it may be
injured, which may assist with developing a diagnostics plan (e.g. ultrasound).