REIDER PART 2
63

Chapter 8_Cervical and Thoracic Spine 323

C6

Figurę 8-38. Brachioradialis reflex (C6).

forearm in a position of neutral rotation so that the radial aspect of the forearm is pointing upward. The wrist is allowed to fali into ulnar deviation. The examiner then taps the radial aspect of the forearm about 4 to 8 cm proximal to the radial styloid (Fig. 8-38). This should produce a visiblc contraction of the brachioradialis mliście and, in many cases, a quick upward motion of the forearm. Because the biceps brachii is innervated by C6 as well as C5, the biceps reflex can also be examined when a C6 radiculopathy is suspected.

Triceps Reflex (C7). The triceps reflex is usually used to assess the C7 nerve root. The triceps reflex is best elicited with the patient in a position of 90° shoulder abduction and 90° elbow flexion. The examiner should support the arm completely, asking the patient to relax all muscula-ture. The examiner should feel that the patients limb would flop back to the side if the examiner released it. When adequate relaxation is sensed, the examiner strikes the triceps tendon just proximal to the olecranon (Fig. 8—39A). Normally, this should cause a visible contraction of the triceps and, sometimes, a slight extension of the elbow. The triceps reflex may also be elicited with the patients arm at the side in a position similar to that used for the biceps reflex (Fig. 8-39B). This position is useful for patients who find the 90° of shoulder abduction uncomfortable.

Grading Reflexes. Because briskness of deep tendon reflexes varies considerably from one individual to another, the examiner should test several reflexes on both sides of the patient to verify that an apparently abnormal reflex is abnormal for that particular patient. Particularly significant is a reflex that is abnormal compared with the corresponding reflex on the opposite side of the body. Reflexes are typically graded as hyporeactive, normal, or

Figurę 8-39. A, Triceps reflex (C7). B, Alternative techniąue.