Shoulder rotator torque and wheelchair dependence differences of national wheelchair basketball association players

358

Shoulder Rotator Torque and Wheelchair Dependence Differences of National Wheelchair Basketball Association Players John Nyland, EdD, PT, Kevin Robinson, MS, PT, David Caborn, MD, Elizabeth Knapp, BS, Tony Brosky, PT, SCS. ABSTRACT. Nyland J, Robinson K, Caborn D, Knapp E, Brosky T. Shoulder rotation torque and wheelchair dependence differences of National Wheelchair Basketball Association players. Arch Phys Med Rehabil 1997;78:358-63.

Objective: Shoulder rotator muscle imbalances can contribute to subacromial impingement. The forces and movement patterns of wheelchair locomotion may contribute to these imbalances. This study attempted to determine whether National Wheelchair Basketball Association players of differing classifications had significant differences (p 5 .05) in concentric isokinetic peak shoulder rotator torque and torque ratios, and wheelchair locomotion dependence. Design: Fifty-seven (class 1 = 12, class 2 = 24, class 3 = 21) of 117 total tournament participants (class 1 = 25, class 2 = 49, class 3 = 43) served as the convenience sample of volunteers for the survey portion, and 33 of these subjects (class 1 = 11, class 2 = 12, class 3 = 10) also entered the isokinetic portion of this study. Setting: National wheelchair basketball tournament. Results: Class 1 and 2 players had greater wheelchair dependence than class 3 players (p 5 .05). Peak torque or torque ratios generally did not differ among player classifications or with other populations. Class 1 players had weaker nondominant shoulder external rotator torque production at 60”/sec (p 5 .03) compared with other classes and at 180”/sec compared with class 3 players (p = .02), suggesting an inability to develop the “attenuation of dominance” noted among other groups. Diminished torque-producing capacity at 60”/sec related to greater wheelchair dependence among class 1 players (p = .034). Conclusions: Class 1 players failed to demonstrate

the acquired shoulder external rotator torque symmetry evident among class 2 and 3 players (with specific weakness of the nondominant shoulder external rotators). This torque symmetry difference was related to their greater dependence on wheelchair locomotion. 0 1997 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation

0

RGANIZED COMPETITIVE wheelchair athletics date back to 1948 and were developed originally as a means to rehabilitate disabled war veterans.’ Individuals with congenital From the University of Kentucky Sports Medicine Center Submitted for publication March 8, 1996. Accepted in revised form September 6, 1996. No commercial party having a direct or indirect interest in the subject matter of this article has or will confer a benefit upon the authors or upon any organization with which the authors are associated. Reprint requests to John Nyland, EdD, PT, K437 Kentucky Clinic, University of Kentucky Sports Medicine Center, Lexington, KY 40536.0284. 0 1997 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation 0003-9993/97/7804-3934$3.00/O

Arch

Phys Med

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Vol 78, April

1977

deformities such as spina bifida, diseases such as polio, and traumatic injuries such as spinal cord injury or amputation are often active participants in wheelchair athletics. The number of disabled athletes participating in competitive sports has rapidly increased, and wheelchair sports have evolved from a rehabilitation process to competitions on local, state, national, and international levels.‘-’ Competitive wheelchair athletes from 6 to 18 years of age form one of the fastest growing areas of wheelchair athletics6 Increased and earlier participation in wheelchair athletics raises further concern over the prevention of sports-related injuries among this population.

THE BENEFITS OF WHEELCHAIR

ATHLETICS

Disabled individuals who assume sedentary lifestyles often have diminished functional capacity, rehabilitation potential, and overall quality of life.’ A sedentary lifestyle can place the disabled individual at greater risk for the development of cardiopulmonary disease, adult-onset diabetes, and hypertension.7 Regular endurance activities for individuals who depend on a wheelchair as their primary method of locomotion may delay the progression of these diseases, reduce the incidence of respiratory infection, counter the development of osteoporosis, and decrease the risk of calculi formation.* Increased habitual activity can also improve self-image9 and have a positive impact on other health behaviors such as smoking or alcohol consumption.”

SHOULDER

INJURY

OCCURRENCE

Dependence on a wheelchair for locomotion (wheeling) and repeated lifting of body weight during transfers place demands on the upper extremities of the disabled that exceed those of able-bodied persons.“,” Wheelchair athletes rely on their upper extremities for both propulsion and weight bearing during daily living and sports activities.* The integrity of the upper extremities is believed to be a major determinant regarding the ultimate level of functional independence of wheelchair athletes.* With increased numbers of participants, and increased levels of competition, sports-related injuries among this population have also increased. In a 1972 survey conducted among American wheelchair athletes, 72% of respondents reported at least 1 injury as a result of sport participation, with soft tissue injuries such as sprains, strains, tendinitis, and bursitis being the most commonly reported.3 Hoeberigs and Verstappen13 reported that 42% of wheelchair basketball athletes developed upper extremity soreness during tournament play, with 34% reporting soreness in the deltoid region. Among National Wheelchair Athletic Association (NWAA) athletes, 61% of total injuries occur at the upper extremity, with 40% of these injuries occurring at the shoulder jointI Shoulder injury and pain are also common among wheelchair-dependent nonathletes.“~‘s~16 Bayley et alI7 reported that 33% of wheelchair-dependent paraplegic persons had chronic,

WHEELCHAIR

BASKETBALL

SHOULDER,

359

Nyland

Class I Complete motor loss above or comparable where there is total loss function originating at T7. Class

at T7 or disability of muscle or above

II

Complete motor loss originating at T8 and descending through and incuding L2 where there may be motor power of hips and thighs. Also included in this class are amputees with bilateral hip disarticulation.

Class

III

All other physical disabilities as related to lower extremity paralysis or paresis originating at or below L3. All lower extremity amputees are included in this class except those with bilateral hip disarticulation (see Class II).

Fig 1. NWBA

player

classifications.

persistent shoulder pain that was clinically diagnosed as subacromial impingement syndrome. Despite being recognized as a common and disabling problem, little has been written regarding the cause, prevention, or treatment of shoulder problems among wheelchair athletes.’

WHEELCHAIR ATHLETIC SUBACROMIAL IMPINGEMENT-MUSCULAR IMBALANCE RELATIONSHIP The primary cause of overuse injury or pain involving the shoulders of wheelchair athletes is believed to be subacromial impingement.* Overuse, lack of proper warm-up, glenohumeral and scapula-thoracic dyskinesia (muscular imbalances), lack of dynamic lumbo-pelvic postural control, axial weight bearing forces, poor shoulder flexibility, repetitive overhead arm positioning, and fatigue may all contribute to subacromial impingement syndrome among wheelchair athletes.3~6~“~1Z~15~21 Exaggerated glenohumeral internal rotation and scapular protraction with downward rotation positioning is common for wheelchair athletes both at rest and during aggressive wheeling.* Repetitive function with the shoulder girdle in this position reportedly promotes subacromial impingement in other athletic22m24and nonathletic populations.*’ When upper extremity weight bearing increases, as during wheelchair locomotion, changes in muscular agonist-antagonist torque-producing ratios similar to those noted after intensive conditioning programs may occur, often leading to greater torque production symmetry (“nondominance”) between

Fig 2. IsokineticTest mal external rotation.

Positioning:

(A) maximal

internal

rotation;(B)

maxi-

extremities and imbalances between opposing muscular groups. 19,26Shoulder muscle imbalances with humeral head depressor weakness (infraspinatus, teres minor, subscapularis, long head of biceps brachii) in combination with repetitive axial subacromial space loading from weight bearing may further exacerbate subacromial impingement among wheelchair athletes.“19 Wheelchair propulsion selectively promotes the development of glenohumeral joint internal rotator (pectoralis major, teres major, latissimus dorsi, subscapularis) and scapular protractor (serratus anterior) torque-producing capacity, thereby creating muscular imbalances.2,27 Dysfunctional sitting posture resulting from neurological deficits or simply poor habits can adversely affect the glenohumeral joint through changes in scapula-thoracic articulation orientation. Subtle changes in glenoid fossa alignment can evoke compensatory muscular stabilization demands that eventually promote joint degeneration. Paraplegic persons with complete Table

NWBA Classification

Class Class Class

1 (n = 12) 2 (n = 24) 3 (n = 21)

Characteristics p > .05.

1: Subject

Demographics

Age (yrs)

Duration of Disability km)

35.7 -C 4 35.8 k 8 34.4 t 7

14.3 i 5 17.8 I 11 19.2 2 11

presented

as mean

Arch

Wheelchair Basketball Playing Experience lvrs)

ll.Oi 5 11.9 t 8 II.82 6

Height (cm)

183 2 IO 180 t 11 184i 10

Weight kg)

8Oi 74-t 88~

18 15 17

+- SD.

Phys

Med

Rehabil

Vol78,

April

1997

360

WHEELCHAIR

Table

2: Wheelchair

Wheelchair

1 (n = 12) 2 (II = 24) 3 (n = 21)

1 and Class

Table

2 r Class

NWBA Classification

3 (p 5 .05).

spinal cord lesions below the second thoracic (T-2) spinal nerve root level can achieve partial sitting postural compensation for decreased erector spinae muscle group function by increased latissimus dorsi and upper trapezius muscle activationzl When dynamic trunk control is compromised, these muscles may serve more as postural stabilizers for the trunk than as prime movers for the upper extremity, thereby further promoting glenohumeral muscular imbalances.‘r The ability to dynamically control sitting posture is vital for proper scapula-thoracic and glenohumeral function and efficient performance of functional tasks with the upper extremities.*l Spinal cord injured subjects tend to sit with their pelvis tilted 15” more posteriorly than normal subjects to enhance sitting balance in the absence of effective dynamic lumbo-pelvic control.28 This sitting posture further promotes inefficient scapula-thoracic and glenohumeral positioning, motion, and torque-producing capacity.25

NWBA RATING

SYSTEM

According to a study performed in 1984, the National Wheelchair Basketball Association (NWBA) includes approximately 1,950 players on more than 16.5 men’s and women’s teams in 27 conferences.13 The NWBA is the oldest organization in the United States representing athletes with locomotor impairments.29 To be eligible for NWBA participation individuals must have permanent severe leg disability or paralysis of the lower portion of the body, as well as the potential for benefiting from participation in wheelchair basketball, and must be denied the opportunity to otherwise play basketball were it not for the wheelchair adaptation. The NWBA favors a functional classification system for its participants based on the quality and quantity of active muscle and the ability to perform specific tasks such as trunk rotation and picking a basketball up from the floor. This functional classification system generates three player categories, ranging from relatively higher spinal cord injured athletes (class l), who are almost exclusively wheelchair dependent, to any of a wide variety of other medical conditions that generally do not result in as great a wheelchair dependence (class 3). Class 3 players often leave their wheelchairs courtside at the completion of play and walk around with or without other assistive devices. Player classifications are denoted in figure 1.30 Although studies have assessed shoulder muscle torque-producing capability2*20,26 and relative wheelchair dependence,6X15 comparison of wheelchair basketball players based solely on their NWBA classification has not been performed. The purpose of this study was to determine if NWBA player classification resulted in statistically significant differences (p 5 .05) in (1) concentric Table

4: Dominant

(DOM)

NWBA Classification

Class Class Class

Phys

as mean

Med Rehabil

(NONDOM)

Shoulder

Class Class Class

1 (n = 11) 2 In = 12) 3 (n = IO)

Values presented p > .05.

3: Peak Shoulder External Rotator and Internal Rotator (IR) Torque ER Peak Torque (Nm), 60%~

IR Peak Torque (Nm), dO”/sec

45.8 i 9.8 42.2 ? 13.6 41.4 k 9.4

74.7 k 11.7 69.4 2 14.9 70.2 k 13.3

as mean

(ER)

ER Peak Torque

IR Peak Torque

(Nm), 180”isec

(NmL 180%ec

36.9 ? 9.2 31.3 ? 12.1 31.2 2 7.2

64.8 f 9.4 58.0 i 13.0 61.3 2 9.2

? SD.

isokinetic peak torque of the shoulder internal and external rotators, (2) the ratio of dominant and nondominant concentric isokinetic peak torque of the shoulder internal and external rotators, and (3) wheelchair dependence for locomotion. Peak torque and torque ratios were also compared and contrasted with other populations.

METHODS Procedures Informed consent was obtained from each participant in the study. Data collection took place during the 13th Annual Bluegrass Invitational Wheelchair Basketball Tournament. Data collection was coordinated by the primary investigator. The NWBA classification was verified from tournament registration applications at the conclusion of the tournament.

Subjects The study population was sampled from the 117 participants (class 1 = 25, class 2 = 49, class 3 = 43) in the basketball tournament. Fifty-seven (class 1 = 12, class 2 = 24, class 3 = 21) players volunteered to participate in the questionnaire portion of this study, which attempted to determine wheelchair dependence as the primary mode of transportation. The following question was used to determine wheelchair dependence: “Excluding motorized vehicles, I use a wheelchair as my primary method of transportation ? percent of the time.” Responses could range from “Neve?’ to “All the Time.” Before answering this question, subjects completed a trial question under the supervision of the principle investigator to become familiar with the visual analog scale (VAS) format and to increase measurement reliability.31 Additional information was obtained regarding the duration of disability, wheelchair basketball playing experience, height, and weight. Of these subjects, 33 (class 1 = 11, class 2 = 12, class 3 = 10) players volunteered to participate in the isokinetic portion of this study. Only subjects who were asymptomatic for upper extremity or trunk pain participated in this portion of the study. Isokinetic testing was performed using a Cybex II isokinetic dynamometer and dual channel recordera and a Biodex Upper Extremity Chair.b The Biodex chair was used for its hydraulic lift capability, which enabled greater ease of transfer while simultaneously enabling replication of the test position described by Cahalan et a1.32 External

Rotator

(ER) and Internal

Rotator

(IR) Peak Torque

Ratios

DOM ER/lR Peak Torque Ratio, 6O%ec

NONDOM ER/IR Peak Torque Ratio, 60”/sec

DOM ER/IR Peak Torque Ratio, 18O”/sec

NONDOM ER/IR Peak Torque Ratio, 180”lsec

.66 k .I1 .60 i .I3 .58 2 .08

.57 i .05 .59 2 .I1 .59 t .I2

.58 ? .08 .53 ? .I1 .50 + .I0

.54 2 .06 .53 i .I2 54 2 .I3

1 (n = 11) 2 (n = 12) 3 (n = IO)

Values presented p > .05.

Arch

and Nondominant

Nyland

Dependence him)

93.1 k 15.0* 76.2 -t 35.4* 30.2 % 30.6

Values presented as mean 2 SD. * Overall F = 26.7 (p = .OOOl); Class

SHOULDER,

Dependence

NWBA Classification

Class Class Class

BASKETBALL

i SD.

Vol78,

April

1977

WHEELCHAIR

Table

5: Nondominant

NWBA

Class Class Class

1 (n = 11) 2 (n = 12) 3 (II = IO)

* NONDOM/DOM ’ NONDOM/DOM

(DOM)

External

.84 k .14+ 1.04 F .24 1.16 z .30

.93 i .I4 1.04 2 .I8 1.0 -t .I7

Ratio, 60”/sec, Ratio, l$O”/sec,

overall overall

F = 4.9 (p = .Ol). Differences F = 4.5 (p = .04). Differences

Age, duration of disability, wheelchair sports experience, height, and weight were not significantly different among player classifications (table 1). Class 1 and 2 players depended on wheelchairs as their primary mode of transportation to a greater extent than class 3 players (p 5 .05) (table 2). Comparisons of peak shoulder external or internal rotator torque at 60”/sec and lSO”/sec failed to reveal statistically significant differences among player classifications (table 3). The dominant upper extremity was defined as that which the subject preferred to use while shooting a basketball. Comparisons of dominant or nondominant peak shoulder external/internal rotator torque ratios at 60”/sec and lXO”/sec failed to reveal significant differences among player classifications (table 4). Comparisons of nondominant/dominant peak shoulder external and internal rotator torque ratios at 60”/sec and 180”/sec found statistically significant decreases in external rotator torque on the nondominant shoulder for class 1 players compared to class 2 and 3 players at 60”/sec, and compared to class 3 players Comparisons

of Wheelchair

* p I

dependence

Dependence Wheelchair

SOUrCe

Wheelchair

Ratio (n = 11) Ratio (n = 12) Ratio (n = IO) values

Ratios

.91 i .I4 1.0 f .I6 .98 ir .I9

RESULTS

Rotator Rotator Rotator

(IR) Peak Torque

.77 2 .11* .97 ir .24 1.0 k .I3

Means and standard deviations were calculated for each variable. Median and range values were also determined for the wheelchair dependence variable. One-way analysis of variance (ANOVA) tests were employed to determine whether significant differences existed among the mean torque variables and wheelchair dependence values of each NWBA classification. When a significant F value occurred, Tukey Honest Significant Difference post hoc comparisons were employed to specify how the groups differed from each other. A probability level of p 5 .05 was chosen for all statistical procedures to demonstrate statistical significance.

1 External 2 External 3 External

Rotator

Ratio, 60‘7s~

Statistical Methods

Class Class Class

(ER) and Internal

NONDOMiDOM IR Peak Torque Ratio, l80”lsec

ER Peak Torque ER Peak Torque

6: Class

Rotator

361

Nyland

NONDOMiDOM ER Peak Torque Ratio, 180”lsec

ER Peak Torque

Torso and forearm stabilization straps were used. Test positioning and motion pattern are presented in figure 2. During isokinetic testing, the upper extremity which was tested first was randomly selected. Before determination of peak shoulder internal or external rotator torque, each subject performed three submaximal practice repetitions. Following this, each subject was instructed to perform five repetitions with maximal effort. This procedure was performed initially at 60”lsec and then at 180”/sec. Standard recorder settings were used for damping, chart speed, and torque scale.33 This procedure was then repeated for the opposite upper extremity. Following completion of isokinetic testing, peak torque values were manually measured per manufacturer’s protocol.33

Table

SHOULDER,

NONDOMiDOM IR Peak Torque Ratio, 60%~

NONDOM/DOM

Classification

(NONDOM)/Dominant

BASKETBALL

presented

Dependence

95.6 t

4.4

66.9 i 25.9 23.9

as mean

Versus

ir 16

from Class 2 (p = .03), Class 3 (p = .02). from Class 2 (p = .ll), Class 3 (p = ,021.

at lSO”/sec (table 5). Comparisons of nondominant/dominant peak shoulder external rotator torque and NWBA player classification by wheelchair dependence found significant differences at 60”/sec between class 1 players and other classes (table 6) (fig 3).

DISCUSSION Comparisons were made among peak shoulder external and internal rotator torque (table 3), dominant and nondominant shoulder external/internal rotator peak torque ratios (table 4), and nondominantldominant shoulder external and internal rotator peak torque ratios (table 5). Comparisons were also made with other studies22,23,32,34”6for peak shoulder external and internal rotator torque (table 7) dominant and nondominant shoulder external/internal rotator peak torque ratios (table 8),22,23,32,34-3g and nondominant/dominant shoulder external and internal rotator peak torque ratios (table 9).22~23*32,34~36 Studies were chosen that used similar isokinetic testing procedures and positions including shoulder positioning (although slight differences in shoulder flexion and abduction angles did occur, and varying isokinetic devices were used). Peak shoulder rotator torques reported in this investigation compared favorably with previous reports of wheelchair athletes and other populations (table 7). Peak dominant and nondominant shoulder external/internal rotator torque ratios (table 4) also compared favorably with previous studies of wheelchair athletes, and other populations (table 8). NondominantIdominant peak shoulder external rotator torque results for class 1 wheelchair basketball players revealed statistical differences when compared to class 2 and 3 players (table 5) and when compared to other athletic populations (table 9). These results indicate that although class 1 wheelchair basketball players fail to demonstrate significant differences in peak torque capacity compared to class 2 or 3 players, they demonstrate a lack of the acquired bilateral shoulder external rotator torque symmetry (attenuation of dominance) reportedly common among other wheelchair athletes2,26 with weaker nondominant shoulder external rotators (table 8). Comparisons of nondominant/dominant peak shoulder external rotation torque at 60”isec and NWBA player classification by wheelchair dependence provided further evidence of differences between class 1 players and other player classes (table 6) (fig 3). Although not primarily assessed in this study, faulty sitting posture may contribute more to the development of glenohumeral joint muscular imbalances among class 1 players more than other wheelchair basketball players. Lesions at or above Nondominant/Dominant Sum-of-Squares

External

Rotator

Torque

Degrees of Freedom

78.2

1

1953.4

1

9.941

Ratios

at 60”lsec F Ratio 6.3 3.6 ,035

1

P .034* ,086 .86

2 SD.

.05.

Arch

Phys Med

Rehabil

Vol 78, April

1997

WHEELCHAIR

0

BASKETBALL

SHOULDER,

Nyland

affect both intrinsic and extrinsic shoulder girdle muscle torque producing capacity. When normal innervation is compromised, scapula-thoracic and glenohumeral muscular imbalances may result, increasing susceptibility to subacromial impingement. Because of their greater wheelchair dependence, and potentially more impaired dynamic trunk control, class 1 wheelchair basketball players may be especially susceptible to subacromial impingement from glenohumeral joint muscular imbalances.

0

0

CONCLUSIONS This studv found that: 1. Differences did not exist among the concentric isokinetic peak shoulder rotator torque or nondominantidominant torque ratios of differing NWBA player classifications or other populations; 2. Differences did exist in nondominant/dominant external rotator torque ratios, with class 1 wheelchair basketball players failing to demonstrate the symmetry of external rotator torque (attenuation of dominance) demonstrated by class 2 or 3 wheelchair basketball players or other populations, with specific weakness of the nondominant glenohumeral joint external rotators; 3. Class 1 wheelchair basketball players were more dependent on wheelchairs as their primary mode of transportation than either class 2 or 3 players, and this dependence related to differences in nondominant external rotator torque-producing capacity. Athletic examinations and conditioning programs of wheelchair basketball players before participation should place particular emphasis on functionally evaluating the entire shoulder joint complex, with emphasis on glenohumeral external rotator and scapular retractor function as integrated members of a global kinetic chain that has an origin primarily from a sitting position. Class 1 players may be at greater risk for developing glenohumeral muscular imbalances than their class 2 or 3 counterparts because of greater wheelchair dependence, inherently

0

Fig 3. Relation external rotator

of wheelchair dependence and nondominantldominant torque at 60”lsec to player classification.

the seventh thoracic (T-7) spinal nerve root level (class 1 by definition) can produce greater and more variable dynamic trunk control and shoulder mobility deficits than either of the other two player classifications. Concurrently, any loss of normal neural function above the T-7 spinal nerve root level may also Table Reference

7: Peak Shoulder

Brown et aP4 (Male Baseball) Cahalan et ai3’ (Healthy Adults) Hageman et all5 (Healthy Adults) Leroux et alI6 (Healthy Adults) McMaster et al*’ (Healthy Males)

(Male

Water

McMaster

(Male

Swimmers)

Values

presented

Table

Males)

as mean

8: Dominant

Rotator

(ER) and Internal

ER Peak Torque 60%X

Citations

et alz3 (Healthy

External

Polo)

(Nm),

Rotator

IR Peak Torque

(IR) Torque (Nm),

60%~

NA 35.3 k 8.1 30.6 2 5.3 32.1 -+ 1.9 NA

NA 62.4 2 19.0 48.6 i 11.0 43.6 i 4.0 NA

NA

NA

39.7 27.1 26.7 29.3 37.1 46.8 37.1 38.6

(DOM)

and Nondominant

Citations

(NONDOM)

External

(Male

Water

McMaster

et a?

(Male

Swimmers)

Soderberg Walmsley

et al38 (Healthy et alz9 (Healthy

Arch

values

presented.

Phys Med

Rehabil

Males) Males) Females)

NA = not applicable.

Vol78,

Ratio,

60%~

Brown et al34 (Male Baseball) Cahalan et a13’ (Healthy Adults) Greenfield et alz7 (Healthy Adults) Hageman et aP5 (Healthy Adults) Leroux et a13’ (Healthy Adults) McMaster et alz2 (Healthy Males)

Mean

k +k + i 2 2 f

IR Peak Torque

(Nm),

18O”/sec

7.1 5.4 7.1 2.1 8.7 10.7 8.7 10.8

56.9 54.2 42.3 39.0 56.7 89.3 56.7 89.9

k ? + t i i + i

9.9 17.6 8.3 3.7 12.7 23.3 12.7 27.1

t SD. NA = not applicable.

Torque

(Healthy

(Nmt,

180%ec

Rotator

IER) Internal

Rotator

DOM EWIR Peak Reference

Comparisons ER Peak Torque

April

1977

Polo)

NONDOM ER/IR Peak Torque Ratio, 60%x

NA .56 .a2 .63 .74 NA

NA .60 NA NA .80 NA

NA

NA

.60 .63

NA NA

(IR) Peak Torque

Ratio

Comparisons

DOM ERilR Peak Torque Ratio, 180%~

NONDOM ERilR Peak Torque Ratio,

.70 .48 NA .59 .72 .65 .55 .65 .45 .61 .60

.72 .54 NA NA .80 .66 .56 .66 .55 NA NA

180”/sec

WHEELCHAIR

Table

9: NONDOM/DOM

External

Reference Citations Brown et al34 (Male Baseball) Cahalan et a13’ (Healthy Adults) Leroux et a136 (Healthy Adults) McMaster et al** (Healthy Males)

(Male

Water

McMaster

(Male

Swimmers)

Mean

values

et alz3 (Healthy presented.

Males)

Polo)

Rotator

BASKETBALL

SHOULDER,

(ER) and Internal

13. 14. 15. 16.

Comparisons NONDOM/DOM IR Peak Torque Ratio, 160%~

NA 1.0 1.0 NA

NA .93 .92 NA

NA

NA

.98 1.05 1.05 .93 .88 1.12 1.01

.93 .93 .94 .90 .85 .99 .91

NA = not applicable.

in the rotator cuff of the elite water polo player. Am J Sports Med 1991; 19:72-5. 23. McMaster WC, Long SC, Caiozzo VJ. Shoulder torque changes in the swimming athlete. Am J Sports Med 1992;20:323-7. 24. McMaster WC, Troup J. A survey of interfering shoulder pain in United States competitive swimmers. Am J Sports Med 1993;21:6770.

25. Calliet R. The shoulder in hemiplegia. Philadelphia: FA Davis, 1980. 26. Calmels P, Berthouze S, Barr& FG, Dome&h M, Minaire P. A comparative study of the muscle strength and mass of the arm flexors and extensors in paraplegic and in nonparaplegic basketball players. Paraplegia 1992;30:509-16. 27. ba;is R, Fe&r; M, Dyrnes D. The competitive wheelchair stroke. Nat1 Strength Conditioning Assoc J 1988: 10:4-10. 28. Hobson D& Tooms RE. Seated lumbar/peivic alignment: a comparison between spinal cord-injured and noninjured groups. Spine 1992; 17:293-g. 29. McCann BC. Wheelchair medical classification system. In: Steadward R, editor. Proceedings of First International Conference on Sport and Training of the Physically Disabled Athlete. Edmonton: University of Alberta, 1979:1-24. 30. NWBA Rules Manual. Lexington (KY): National Wheelchair Basketball Association, 1992. 31. Flandry F, Hunt J, Terry G, Hughston J. Analysis of subjective knee complaints using visual analog scales.Am J Sports Med 1991; 19:1128. 32.

501-8.

12.

Ratio

NONDOMIDOM ER Peak Torque Ratio, lSO”/sec

References

11.

(IR) Peak Torque

NONDOMiDOM IR Peak Torque Ratio, 60”lsec

1. Strauss R. Sports medicine. Philadelphia: WB Saunders, 1984. 2. Burnham RS, May L, Nelson E, Steadward R, Reid DC. Shoulder pain in wheelchair athletes: the role of muscle imbalance. Am J Sports Med 1993;21:238-42. 3. Curtis KA, Dillon DA. Survey of wheelchair athletic injuries: common patterns and prevention. Paraplegia 1985;23:170-5. 4. Guttman L. Development of sports for the disabled. In: Grupe 0, editor. Sports in the modern world: problems and chances. Berlin: Springer Verlag, 1973:254-6. 5. Mangus BC. Sports injuries, the disabled athlete, and the athletic trainer. Athl Train 1987;22:305-10. 6. Wilson PE, Washington RL. Pediatric wheelchair athletics: sports injuries and prevention. Paraplegia 1993; 3 1:330-7. I. Pitetti KH. Introduction: exercise capacities and adaptations of people with chronic disabilities-current research, future directions, and widespread applicability. Med Sci Sports Exert 1993;25:421-2. 8. Cowell LL, Squires WG, Raven PB. Benefits of aerobic exercise for the paraplegic: a brief review. Med Sci Sports Exert 1986; 18:

10.

Rotator

NONDOM/DOM ER Peak Torque Ratio, 60%~

less trunk control, and a lack of acquired shoulder external rotator torque symmetry (as noted among class 2 and 3 players) with specific weakness of the nondominant glenohumeral external rotators. Further research is necessary with greater subject numbers while attempting to establish the clinical significance of these findings with functional capacity.

9.

363

Nyland

Bandura A. Self-efficacy: towards a unifying theory of behavioral change. Psycho1 Rev 1977;84:191-215. Shepherd R. Sports medicine and the wheelchair athlete. Sports Med 1988;4:226-47. Barber DB, Gall NG: Osteonecrosis: an overuse injury of the shoulder in paraplegia: case report. Paraplegia 1991;29:423-6. Pentland WE, Twomey LT. The weight-bearing upper extremity in women with long term paraplegia. Paraplegia 1991;29:521-30. Hoeberigs JH, Verstappen FT. Muscle soreness in wheelchair basketballers. Int J Sports Med 1984;5 Suppl:177-9. Ferrara MS, Buckley WE, McCann BC, Limbird TJ, Powell JW, Rob1 R. The injury experience of the competitive athlete with a disability: prevention implications. Med Sci Sports Exert 1992;24:184-8. Nichols PJ, Norman PA, Ennis JR. Wheelchair user’s shoulder? Stand J Rehabil Med 1979; 11:29-32. Wing PC, Tredwell SJ. The weightbearing shoulder. Paraplegia

57. 33.

34.

35.

36.

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1983;21:107-13.

17 Bayley JC, Co&ran TP, Sledge CB. The weight-bearing shoulder: the impingement syndrome in paraplegics. J Bone Joint Surg 1987; 69-A:676-8. 18. Ferrara MS, Davis RW. Injuries to elite wheelchair athletes. Paraplegia 1990;28:335-41. 19. Madorsky JG, Curtis KA. Wheelchair sports medicine. Am J Sports Med 1984; 12:128-32. 20 Rodgers MM, Gayle GW, Figoni SF, Kobayashi M, Lieh J, Glaser RM. Biomechanics of wheelchair propulsion during fatigue. Arch Phys Med Rehabil 1994;75:85-93. 21 Seelen HA, Vuurman EF. Compensatory muscle activity for sitting posture during upper extremity task performance in paraplegic persons. Stand J Rehab Med 1991;23:89-96. 22 McMaster WC, Long SC, Caiozzo VJ. Isokinetic torque imbalances

Cahalan TD, Johnson ME, Chao EYS. Shoulder strength using the Cybex II isokinetic dynamometer. Clin Orthop Rel Res 1991;271:249-

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Cybex, Division of Lumex Corporation. Isolated joint testing and exercise: a handbook for using the Cybex II and U.B.X.T Ronkonkoma (NY): Cybex, 1984. Brown LP, Niehues SL, Harrah A, Yovorsky P, Hirshman HP. Upper extremity range of motion and isokinetic strength of the internal and external shoulder rotators in major league baseball players. Am J Sports Med 1988; 16:577-85. Hageman PA, Mason DK, Rydlund KW, Humpal SA. Effects of position and speed on eccentric and concentric isokinetic testing of the shoulder rotators. J Orthop Sports Phys Ther 1989; 1164-9. Leroux JL, Codine P, Thomas E, Pocholle M, Mailhe D, Blotman F. Isokinetic evaulation of rotational strength in normal shoulders and shoulders with impingement syndrome. Clin Orthop Rel Res 1994;304:108-15. Greenfield BH, Donatelli R, Wooden MJ, Wilkes J. Isokinetic evaluation of shoulder rotational strength between the plane of scapula and the frontal plane. Am J Sports Med 1990; 18:124-g. Soderberg GJ: Blaschak MJ. Shoulder internal and external peak torque production through a velocity spectrum in differing positions. J O>hip Sports Phys yher 1987;8:518-24. Walmslev RP, Szvbbo C. Comuarative studv of the torque generated by the shoulder internal and external rotaior muscles in-different positions and at varying speeds. J Orthop Sports Phys Ther 1987; 9:217-22. Suppliers

a. Cybex Division of Lumex, Inc., 2100 Smithtown Avenue, Ronkonkoma, NY 11779. b. Biodex Medical Systems, Inc., 20 Ramsay Road, Shirley, NY 119670702.

Arch

Phys Med

Rehabil

Vol78,

April

1997