Page 102 - Canine Lameness

74 5 The Rehabilitation Examination

(B)

(A)

(C)

Figure 5.4 Flexibility versus PROM of the hamstrings/stifle joint: when testing stifle extension PROM and
end-feel, the muscles resisting stifle extension (i.e. the hamstring group) must be on slack to eliminate their
influence on osteokinematic end-feel and goniometric measurements. This is accomplished by positioning
the hip in extension. If the hip is placed in flexion, flexibility of the hamstrings is tested. This concept is
illustrated using the semimembranosus muscle as an example (this muscle has two bellies: the cranial belly,
a hip extender and the caudal belly, a hip extender and stifle flexor). Given that flexibility testing means
performing the opposite joint motion of the concentric contraction of a muscle, if (A) the hip is placed in
flexion and the stifle in extension, the flexibility of both semimembranosus bellies is evaluated. If (B) all
joints are placed in extension PROM of the stifle and hip joint can be accurately measured, since both
bellies are on slack. If (C) the hip and stifle are placed in flexion, the flexibility of the cranial
semimembranosus belly only is tested.

testing extension, the joints should be positioned in extension. For example, when testing stifle
extension and osteokinematic end‐feel, the tester must place the hamstring muscle group on slack
(i.e. by extending the hip joint). If this is not performed, hamstring flexibility, rather than PROM
of the stifle joint, is tested (Figure 5.4). PROM testing positions for all major joints, current pub-
lished measurements and flexibility testing positions for the common muscles that may influence
PROM at each joint can be found in Tables 5.3 and 5.4.
It is important to note that there are ranges of motion where single‐joint muscles cannot be
placed on slack – this will always influence subjective end‐feel and objective goniometric
measurements. For example, both the supraspinatus and biceps brachii muscles cross the cranial
aspect of the shoulder joint (i.e. act as shoulder extenders). However, the supraspinatus is unable
to be placed on slack when testing flexion PROM of the shoulder joint because it crosses only a
single joint. The biceps brachii, on the other hand, can be placed on slack by flexing the elbow dur-
ing shoulder flexion PROM testing. Similarly, other muscles that cross multiple joints such as the
humeral head of the flexor carpi ulnaris and the gastrocnemius cannot be placed on slack when
testing for PROM of carpus extension or tarsal flexion, respectively.
The second confounding factor in PROM testing is improper use and placement of the universal
goniometer. Steps necessary to perform accurate goniometry are outlined in Figure 5.5 and