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© 1996 The Journal of Bone and Joint Surgery, Inc. The Effect of a Flexion Contracture of the Elbow on the Ability to Transfer in Patients Who Have Quadriplegia at the Sixth Cervical Level*  , DOWNEY, CALIFORNIAInvestigation performed at the University of Southern California Department of Orthopaedics at Rancho Los Amigos Medical Center, Downey
We studied six patients (twelve upper extremities) who had quadriplegia at the sixth cervical level. Our purpose was to evaluate how the loss of terminal extension of the elbow adversely affected the ability of the patient to perform transfers with a sliding board and so-called depression raises (lifting of the body with use of the extended upper extremities to reduce the pressure on the ischial tuberosities). Function of the triceps muscle was considered to be absent in eight upper extremities and present in four. A flexion contracture of the elbow was simulated with use of a specially fabricated, hinged elbow brace. Terminal extension was progressively limited, in 5-degree increments, until the patient was no longer able to perform the transfer or the depression raise. The mean flexion contracture at which the patient could not perform the transfer or the depression raise was approximately 25 degrees when function of the triceps was absent and approximately 50 degrees when function of the triceps was intact. The results of this study emphasize the importance of maintaining the full range of motion of the elbow in a patient who has high-level quadriplegia. In a patient who has quadriplegia at the sixth cervical level who otherwise would be independent with regard to transfer skills and mobility in bed, a flexion contracture of the elbow of approximately 25 degrees or more can result in the loss of a functional level and render the patient as dependent as one who has quadriplegia at the fifth cervical level.
Few studies regarding function of the elbow have addressed the population of patients who have a spinal cord injury. In an individual who is neurologically intact, the primary function of the elbow joint is to assist in the placement of the hand in space. In a patient who has a spinal cord injury, the elbow has a critical role in weight-bearing functions, transfers, and mobility in bed. In a patient who has a spinal cord injury, range of motion of the elbow may be lost as a result of direct trauma, contracture, muscle imbalance, or heterotopic ossification. Functional goals primarily are determined by the level of the spinal cord injury. A loss in the range of motion of the elbow can have a major effect on a patient's level of independence9. This is especially true for a patient who has quadriplegia at the sixth cervical level, as such a patient may have only minimum strength and stability in the shoulder girdle and the proximal part of the upper extremity with which to perform transfers independently with use of a sliding board and to accomplish so-called depression raises (forward bending and lifting of the body at regular intervals to relieve pressure on the ischial tuberosities). In addition, when function of the triceps muscles is absent or weak, a flexion contracture of the elbow may develop as a result of the unbalanced flexion force of the biceps, brachioradialis, and brachialis muscles. Such a contracture may result in a loss of the ability to transfer, thereby further limiting the levels of function and independence. The purpose of the present study was to evaluate how the loss of terminal extension of the elbow adversely affects the function and independence of patients who have quadriplegia at the sixth cervical level by limiting their ability to perform transfers and depression raises independently.
Both upper extremities of six patients were evaluated. All patients had complete quadriplegia at the sixth cervical functional level. The functional level10 was determined by the most caudad level of bilaterally intact sensation and muscle function; to be included in the study, the patient had to have a grade4 of at least fair-plus (3+/5) on manual muscle-testing of the biceps in both extremities. All patients had a similar level of baseline function: they were able to perform a transfer with use of a sliding board and to perform a depression raise and then maintain the position for five seconds. The mean interval between the onset of quadriplegia and the testing was four years (range, one to nine years). The patients included four men and two women; the average age at the time of the injury was thirty-three years (range, twenty-four to forty-three years). Four injuries were the result of a motor-vehicle accident, one was caused by a gunshot wound, and one was the result of a diving accident. The mean weight of the patients was sixty-seven kilograms (range, forty-nine to seventy-six kilograms). All patients had full passive extension and at least 130 degrees of active flexion of the elbow. The average pronation of the forearm was 57 degrees (range, 40 to 65 degrees), and the average supination was 78 degrees (range, 65 to 85 degrees). Motor strength was determined by manual muscle-testing performed by one surgeon (J. G.) and one physical therapist and was graded according to the system described by DeGowin and DeGowin. According to this system, grade 0 indicates no strength and no evidence of muscle contractility; grade 1, trace (10 per cent) strength and slight contraction but no motion of the joint; grade 2, poor (25 per cent) strength and the inability to move the joint against gravity; grade 3, fair (50 per cent) strength and the ability to move the joint slightly against gravity; grade 4, good (75 per cent) strength and the ability to move the joint against gravity and against slight resistance; and grade 5, normal (100 per cent) strength. The twelve upper extremities were divided into two groups, according to the presence or absence of function of the triceps. Patients in whom the strength of the triceps was grade 3 or less were unable to extend the elbow against slight resistance and therefore were not considered to have function of the triceps muscle; conversely, those in whom the strength of the triceps was grade 4 or 5 were considered to have function of the triceps muscle. Function of the triceps was absent in eight upper extremities and was present in four (Table I).
After the patient had been evaluated clinically, a specially manufactured hinged brace was placed on the right or the left upper extremity. The brace could be adjusted to simulate a flexion contracture of the elbow by allowing full, unrestricted flexion of the elbow while limiting extension. The brace was constructed with use of metal polycentric hinges with an eccentric cam and a changing axis of rotation to approximate the anatomical motion of the elbow more closely. Pronation and supination of the forearm were unrestricted in the sleeve of the brace. The patient performed consecutive trials of two functional tasks while wearing the brace. Although only one extremity was tested at a time, the use of both upper extremities was necessary to perform the tasks. The sequence and instructions were the same for all patients. For the first task, the patient was instructed to transfer, with use of a polished wooden sliding board, from a wheelchair to a mat on a level surface. The patient first performed the task with the brace unlocked (to permit unlimited extension and flexion of the elbow) and then repeated the task as extension of the elbow was progressively limited (in 5-degree increments) to simulate different degrees of flexion contracture. This continued until the patient could no longer perform the task. Rest periods were allowed as needed by the patient or as determined by the physical therapist. The degree of simulated flexion contracture was determined, before each attempt, from three separate measurements on a manual goniometer (Smith, Nephew, Rolyan, Menomone Falls, Wisconsin) that was accurate to within 1 degree. For the second task, the patient sat on a mat and was instructed to perform a depression raise and to maintain the position for five seconds. We believe that such a maneuver reflects the patient's ability to relieve pressure on the ischial tuberosities. As with the first task, extension of the elbow was progressively limited (in 5-degree increments) until the patient could no longer perform the depression raise. Because of the non-parametric nature of the system for grading the muscle strength, the Kendall tau C test was used as a measure of association.
Testing of the eight upper extremities in which function of the triceps was absent (grade-2 or grade-3 strength) demonstrated that the patients were unable to perform the transfer when the simulated flexion contracture was a mean (and standard deviation) of 25 ± 0.9 degrees; the patients were unable to perform the depression raise when the flexion contracture was a mean of 24 ± 0.6 degrees. Testing of the four upper extremities in which function of the triceps was present (grade-4 strength) showed that the patients were unable to perform the transfer when the flexion contracture was a mean of 50 ± 0.0 degrees and were unable to perform the depression raise when the flexion contracture was a mean of 48 ± 2.5 degrees (Table I). A significant association was noted between the strength of the extremity (the presence or absence of function of the triceps) and the maximum degree of flexion contracture at which the transfer (p = 0.0008) or the depression raise (p = 0.02) could be accomplished. With the numbers available, we found no significant differences between the findings for the dominant and the non-dominant upper extremities.
The goals of treatment for a patient who has a spinal cord injury are to minimize functional deficits, to prevent complications, and to maximize all remaining function so that the patient can return to a productive life in society. Specific goals and expectations are based on the functional level of the injury, which is determined by the most caudad level of bilaterally intact sensation and muscle function. A gain or loss of a single functional level can have dramatic implications. A patient who has a fifth cervical functional level has only partial control of the shoulder and weak flexion of the elbow and therefore needs assistance for all transfers and with mobility in bed3,10. A patient who has a sixth cervical functional level has control of the shoulder, flexion of the elbow, extension of the wrist, and supination of the forearm. Depending on the degree, if any, of sparing or return of the function of the seventh cervical nerve root, such a patient may have function of the triceps and some function of the hand and therefore may be able to dress and to perform transfers independently3,10. This gain in a single functional level may allow the patient to recover some measure of independence in the activities of daily life. Functional goals are limited by an inadequate range of motion at the elbow. Morrey et al.6,7 evaluated fifteen activities of daily living and determined that most activities could be performed within a 100-degree arc of flexion of the elbow (between 30 and 130 degrees) and within a 100-degree arc of rotation of the forearm (equally divided between pronation and supination). Functional range of motion, as determined for an individual who is neurologically intact, is not applicable to a patient who has a spinal cord injury. In an individual who is neurologically intact, the elbow is used most commonly for activities involving reach and for positioning of the hand; it is used less commonly, if at all, for transfers and support of the body1,6,8. In a patient who has quadriplegia, the elbow assumes a critical role during weight-bearing functions and transfers in addition to its role in reaching and positioning of the hand. A patient who has quadriplegia at the sixth cervical level is susceptible to a flexion contracture of the elbow because of an imbalance of the forces of flexion and extension of the elbow. Strength of the triceps is determined by the degree of sparing of the seventh cervical nerve root, which varies among patients. In the current study, the strength of the triceps was clearly associated with the maximum degree of flexion contracture at which the patient was able to perform tasks independently. Patients who were able to extend the elbow only slightly or even completely against gravity but not against resistance (grade-2 or grade-3 strength) were unable to tolerate a 25-degree flexion contracture of the elbow (that is, the elbow flexed and collapsed under the weight of the body when the patient attempted to perform the transfer), while those who were able to extend the elbow completely against gravity and against some resistance (grade-4 strength) were unable to tolerate a 50-degree flexion contracture of the elbow. We tested only one extremity at a time, but it is important to remember that two stable upper extremities are necessary to maintain the ability to transfer and to perform a depression raise. If a flexion contracture develops in either upper extremity, a patient who has quadriplegia may lose the ability to use the upper extremities for balance and thus may become unable to perform these tasks. If a flexion contracture is present in both upper extremities, this ability may be lost at a smaller degree of flexion. An appreciation of the anatomy and the mechanics of the elbow joint is important for an understanding of the function of the elbow when it is used for weight-bearing functions and transfers. With the elbow extended, the olecranon is seated in the olecranon fossa, the anterior capsule is taut, and the articulation stabilizes the joint independent of ligamentous competency and muscle balance. As the elbow is flexed, maintenance of the flexed position under axial load depends on ligamentous competency and isometric muscle balance of the flexor and extensor muscles of the elbow. Patients in whom strength of the triceps is absent or weak rely on the ability to lock the elbows in extension mechanically for the performance of transfers or depression raises. We recognize that accurate and reproducible objective tests of strength and measurements of angles are difficult to perform and interpret. Despite its limitations, a standard hand-held goniometer, when used by a skilled observer, can allow flexion and extension of the elbow and pronation and supination of the forearm to be measured with a margin of error of less than 5 degrees2. Although the grading of slight decreases in muscle strength is subjective, the delineation between patients who can extend the elbow against gravity and resistance and those who cannot is obvious. The implications of a flexion contracture of the elbow in a patient who has a spinal cord injury are clear. The results of the present study reaffirm the necessity to maintain a full range of motion, especially extension, in the early phase of rehabilitation. An operative release should be considered for a patient in whom strength of the triceps is weak or absent and who has a flexion contraction of the elbow that cannot be reduced to less than 25 degrees with non-operative measures. In addition, early reconstruction of the triceps by transfer of the posterior half of the deltoid to the triceps aponeurosis, as described by Moberg, may help to prevent the development of a flexion contracture of the elbow. In a patient who has quadriplegia at the sixth cervical level and weak or absent function of the triceps and who otherwise would be independent with regard to transfer skills and mobility in bed, a flexion contracture of the elbow can result in the loss of an essential functional level and render the patient as dependent as one who has quadriplegia at the fifth cervical level.
*No benefits in any form have been received or will be received from a commercial party related directly or indirectly to the subject of this article. No funds were received in support of this study.
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