Examples of muscular strength tests for the upper extremity
This is an excerpt from Effective Functional Progressions in Sport Rehabilitation by Todd S. Ellenbecker,Mark De Carlo & Carl DeRosa.
Objective assessment of muscular strength in the upper extremity is indicated to determine the presence of muscular strength deficiencies as well as to monitor progress during exercise progression. Although not always feasible, the use of a handheld dynamometer or isokinetic dynamometer is recommended to provide the highest degree of accuracy and represent muscular strength relationships (e.g., bilateral comparisons and unilateral strength ratios). Specific test positions have been described by Daniels and Worthingham (1980) and Kelly, Kadrmas, and Speer (1996) for testing the rotator cuff and scapular musculature. Of key importance is the close monitoring of external and internal rotation strength in the neutral position as well as in 90° of glenohumeral joint abduction. These can be tested bilaterally and compared. Close monitoring of the medial scapular border is also necessary, specifically during external rotation testing. If the evaluator notes significant movement of the medial border of the scapula away from the thorax during testing of external rotation with the arm in neutral abduction or adduction at the side, this constitutes a “flip sign.” This indicates a lack of scapular stabilization and points the evaluator to include scapular stabilization exercise progressions in the person's exercise programming.
Additionally, the empty can test has been used to test for supraspinatus strength and can also be used as a provocation test to evaluate rotator cuff pathology (Itoi et al. 1999). Although all muscles of the upper extremity can be tested manually, the rotator cuff and scapular muscles are perhaps of greatest importance during functional screening. Distal strength testing using a hand-grip dynamometer should reveal significantly greater dominant-arm strength in baseball pitchers and tennis players (Ellenbecker and Mattalino 1997b).
Isokinetic testing performed at 90° of glenohumeral joint abduction is recommended for screening overhead athletes. This joint position more-specifically addresses muscular function required for overhead activities (Bassett, Browne, and Morrey 1994). Descriptive data profiles for throwing athletes (Wilk et al. 1993; Ellenbecker and Mattalino 1997b) as well as for elite junior tennis players (Ellenbecker and Roetert 2003) are listed in tables 3.1 through 3.5. These data provide objective information regarding the normal torque-to-body-weight ratios as well as external rotation and internal rotation (ER/IR) ratios used in the interpretation of instrumented upper extremity strength testing.
Table 3.1 Isokinetic Peak Torque-to-Body-Weight and Work-to-Body-Weight Ratios for 147 Professional Baseball Pitchers
INTERNAL ROTATION | EXTERNAL ROTATION | |||
Speed | Dominant Arm | Nondominant Arm | Dominant Arm | Nondominant Arm |
210º/sec | ||||
Torque | 21% | 19% | 13% | 14% |
Work | 41% | 38% | 25% | 25% |
300º/sec | ||||
Torque | 20% | 18% | 13% | 13% |
Work | 37% | 33% | 23% | 23% |
Data were obtained on a Cybex 350 concentric isokinetic dynamometer.
Data from T.S. Ellenbecker and A.J. Mattalino, 1997, “Concentric isokinetic shoulder internal and external rotation strength in professional baseball pitchers,” Journal of Orthopaedic Sports Physical Therapy 25: 323-328.
Table 3.2 Isokinetic Peak Torque-to-Body-Weight Ratios for 150 Professional Baseball Pitchers
INTERNAL ROTATION | EXTERNAL ROTATION | |||
Speed | Dominant Arm | Nondominant Arm | Dominant Arm | Nondominant Arm |
180º/sec | 27% | 17% | 18% | 19% |
300º/sec | 25% | 24% | 15% | 15% |
Data were obtained on a Biodex isokinetic dynamometer.
Data from K.E. Wilk et al., 1993, “The strength characteristics of internal and external rotator muscles in professional baseball pitchers,” American Journal of Sports Medicine 21: 61-66.
Table 3.3 Isokinetic Peak Torque-to-Body-Weight Ratios and Single Repetition Work-to-Body-Weight-Ratios in Elite Junior Tennis Players
DOMINANT ARM | NONDOMINANT ARM | |||
Peak Torque (%) | Work (%) | Peak Torque (%) | Work (%) | |
External rotation (ER) | ||||
Male, 210º/sec | 12 | 20 | 11 | 19 |
Male, 300º/sec | 10 | 18 | 10 | 17 |
Female, 210º/sec | 8 | 14 | 8 | 15 |
Female, 300º/sec | 8 | 11 | 7 | 12 |
Internal rotation (IR) | ||||
Male, 210º/sec | 17 | 32 | 14 | 27 |
Male, 300º/sec | 15 | 28 | 13 | 23 |
Female, 210º/sec | 12 | 23 | 11 | 19 |
Female, 300º/sec | 11 | 15 | 10 | 13 |
A Cybex 6000 series isokinetic dynamometer and 90° of glenohumeral joint abduction were used. Data are expressed in foot-pounds per unit of body weight for ER and IR.
Data from T.S. Ellenbecker and E.P Roetert, 2003, “Age specific isokinetic glenohumeral internal and external rotation strength in elite junior tennis players,” Journal of Science and Medicine in Sport 6(1): 63-70.
Table 3.4 Unilateral External Rotation and Internal Rotation Ratios in Professional Baseball Pitchers
Dominant Arm | Nondominant Arm | |
210º/seca | ||
Torque | 64 | 74 |
Work | 61 | 66 |
300º/seca | ||
Torque | 65 | 72 |
Work | 62 | 70 |
180º/secb | ||
Torque | 65 | 64 |
300º/secb | ||
Torque | 61 | 70 |
aData from, T.S. Ellenbecker and A.J. Mattalino, 1997, “Concentric isokinetic shoulder internal and external rotation strength in professional baseball pitchers,” Journal of Orthopaedic Sports Physical Therapy 25: 323-328. bData from W.E. Wilk et al., 1993, “The strength characteristics of internal and external rotator muscles in professional baseball pitchers,” American Journal of Sports Medicine 21: 61-66.
Table 3.5 Isokinetic External Rotation/Internal Rotation Ratios in Elite Junior Tennis Players
DOMINANT ARM | NONDOMINANT ARM | |||
ER/IR ratio | Peak torque (%) | Work (%) | Peak torque (%) | Work (%) |
Male, 210º/sec | 69 | 64 | 81 | 81 |
Male, 300º/sec | 69 | 65 | 82 | 83 |
Female, 210º/sec | 69 | 63 | 81 | 82 |
Female, 300º/sec | 67 | 61 | 81 | 77 |
A Cybex 6000 series isokinetic dynamometer and 90º of glenohumeral joint abduction were used. Data are expressed as ER/IR ratios representing the relative muscular balance between the external and internal rotators.
Data from T.S. Ellenbecker and E.P. Roetert, 2003, “Age specific isokinetic glenohumeral internal and external rotation strength in elite junior tennis players,” Journal of Science and Medicine in Sport 6(1): 63-70.
Muscular imbalances caused by repetitive and forceful internal rotation during the acceleration of the throwing motion, tennis serve, and forehand can lead to unilateral muscular imbalances on the dominant arm between the external and internal rotators and jeopardize optimal muscular stabilization. Careful monitoring of the external and internal rotation unilateral strength ratio is an integral measure of musculoskeletal testing programs for return to sport as well as injury prevention and assists in the determination of optimal application of exercise programs for the overhead athlete.
Learn more about Effective Functional Progressions in Sport Rehabilitation.
More Excerpts From Effective Functional Progressions in Sport Rehabilitation
SHOP
Get the latest insights with regular newsletters, plus periodic product information and special insider offers.
JOIN NOW