CR 8- 13
Identifying Links Between a Patient's Complaints and Abnormal Joint Mobility:
A 60-yr old male patient came to physical therapy with complaints of shoulder pain. He reported a history of a severe "shoulder" fracture from a motorcycle accident 30 years earlier. He noted that he had never regained normal shoulder mobility. However, he reported that he had good functional use of his shoulder. He owned a gas station and was an auto mechanic and was able to function fully in those capacities, but he reported increasing discomfort in his shoulder during or after activity. He noted that the pain was primarily on the "top" of his shoulder. Active and passive ROM were equally limited in the symptomatic shoulder: 0° to 80° of flexion, 0° to 70° abduction, and 0° medial and lateral rotation. Palpation during ROM revealed a 1:1 ratio of scapular to arm-trunk motion, revealing that all of the arm-trunk motion was coming from the scapulothoracic joint. Palpation revealed tenderness and crepitus at the acromioclavicular joint during shoulder movement. These findings suggested that in the absence of glenohumeral joint motion, the sternoclavicular and AC joints developed hypermobility as the patient maximized shoulder function, ultimately resulting in pain at the AC joint. This impression was later corroborated by radiological findings of complete fusion of the glenohumeral joint and osteoarthritis of the AC joint. Since there was no chance of increasing glenohumeral joint mobility, treatment was directed toward decreasing the pain at the AC joint.
Identifying tightness of the brachialis muscle
As a one joint muscle, tightness of the brachialis produces a flexion contracture similar to the effects of capsular tightness at the elbow, that is, unchanged by shoulder or forearm position. Therefore, tightness of the brachialis can be distinguished from tightness of the biceps brachii by examining the effects of shoulder position on elbow extension ROM. However, the clinician must then distinguish between brachialis and capsular tightness. The only way to make this distinction is by identifying the end-feel. end-feel , described in chapter 11, is the tactile sensation the examiner receives when a joint is moved passively to the end of its available ROM. A joint motion limited by tight muscular tissue feels rubbery or springy at the end range. A joint with an abnormally tight capsule produces a firmer, less springy end feel. Of course at the elbow, the restriction could be the result of tightness in both the brachialis and the capsule, perhaps from chronic joint inflammation with concomitant elbow flexion positioning for comfort
Latissimus Dorsi Pedicle for Reconstructive Surgery:
Because of its size and vascular supply from multiple arteries, the latissimus dorsi is a frequent source of grafting material for reconstructive surgery, including wound closures and breast reconstruction. Such surgery can significantly impair the strength of the shoulder from which the latissimus dorsi is taken.
Altering the position of the glenohumeral joint allows the clinician to selectively assess specific portions of the glenohumeral capsuloligamentous complex. For example, lateral rotation of the glenohumeral joint reduces the amount of anterior translation of the humeral head by several millimeters. If the clinician assesses anterior glide of the humeral head with the joint laterally rotated and does not observe a reduction in the anterior glide excursion, the clinician may suspect injury to the anterior capsuloligamentous complex. Similarly, by altering the position of the glenohumeral joint, the clinician can direct treatment toward a particular portion of the complex. Anterior glide with the glenohumeral joint abducted applies a greater stretch to the inferior glenohumeral ligament than to the superior and middle glenohumeral ligaments.
Clinical bottom line: A thorough understanding of the attachment sites and orientation of the glenohumeral ligaments, with respect to the glenohumeral joint, provides the clinician with knowledge for assessing and treating different portions of the glenohumeral capsuloligamentous complex. The clinician can also use such knowledge to reduce the loads on an injured or repaired structure.
Early total elbow replacement used strict hinge joint devices. Such devices frequently failed because the device began to loosen. More recent developments include unlinked and "semiconstrained" elbow joint implants that allow slight frontal and transverse plane joint mobility during flexion and extension. These devices have exhibited fewer problems with loosening
Clinical bottom line: Although the elbow appears at first to be a simple hinge joint,the complex accessory motions among the humerus, ulna, and radius make total joint replacement difficult. Complications and failure of total elbow arthroplasties remain higher than those of total hip or knee arthroplasties.
A thirty-something female came to physical therapy complaining of a gradual onset of shoulder pain. She was an artist whose primary art form was oil painting. She was working on a new project using a very large canvas that required prolonged elevation of her painting hand above the level of her head. The patient began to notice shoulder pain while working. She reported that the pain began in the first week of the new project and generally appeared only after a few hours of work. However, the pain was growing more intense and lasting longer after each painting session. The patient's initial evaluation occurred on a Monday morning. She had not painted for 3 days. She denied pain at the time of the evaluation, and no tests elicited pain. She was instructed to return to physical therapy after several days of painting. She was also instructed to schedule the visit after a full day of painting. At the time of the patient's second visit, she had slight pain with palpation at the superior aspect of the greater tubercle. ROM was full and pain-free, and isometric contractions of the shoulder in the neutral position were strong but slightly painful. Resisted shoulder abduction was mildly painful, especially in mid-range. The pain increased with repetitions. These findings were consistent with mild impingement or with irritation of the supraspinatus tendon. The therapist hypothesized that the task of painting on such a large canvas was fatiguing the rotator cuff muscles, which gradually lost their ability to stabilize the glenohumeral joint. As stability decrease, superior glide of the glenohumeral joint increased and gradually allowed impingement of the tendon. This hypothesis is consistent with the findings reported in the literature. The patient's history revealed that the job required prolonged periods of increased shoulder elevation, which was a new activity for her, so the muscles were untrained for this strenuous activity. (The patient had not recognized this as a new or strenuous activity). She was treated with strengthening and endurance exercises for the rotator cuff muscles and was instructed to take frequent rests while painting, to avoid excessive fatigue. The patient reported decreased pain in 1 week and denied pain while painting after 4 weeks.
Clinical bottom line: An understanding of the normal kinematics and motor control of the shoulder helps the clinician develop an appropriate exercise regimen to address the patient's complaints.
Magermans et al. report the shoulder mobility required in diverse activities of daily living (ADL). Activities such as combing one's hair use an average of 90° of glenohumeral flexion or abduction, 70° of lateral rotation of the shoulder, and approximately 35° of concomitant scapular upward rotation. In contrast, personal hygiene activities such as perineal care use glenohumeral hyperextension and essentially full medial rotation ROM.
Clinical bottom line: As the clinician strives to help a patient regain or maintain functional independence, the clinician must work to ensure that the mobility needed for function is available and that all four components of the shoulder complex contribute to the mobility appropriately.
Shoulder, or subacromial, impingement syndrome results from a persistent or repeated compression of the structures within the subacromial space, the space between the acromion process and humeral head. As noted earlier in the chapter, abnormal humeral axial rotation may contribute to the compressive forces leading to impingement. Another possible source of impingement is abnormal scapulothoracic motion during shoulder elevation. Either excessive scapular internal rotation or anterior tilt could narrow the subacromial space and produce compression of the subacromial contents. Repeated or prolonged compression could cause an inflammatory response resulting in pain.
Clinical bottom line: Assessment of scapulothoracic motion during shoulder elevation should be part of a compressive evaluation of the shoulder complex.
Abnormal scapular positions have been implicated in several forms of shoulder dysfunction. Abnormal orientation of the glenoid fossa has been associated with instability of the glenohumeral joint. In addition, excessive anterior tilting and decreased upward rotation have been reported in individuals with shoulder impingement syndromes during active shoulder abduction.
Clinical bottom line: Careful evaluation of scapular position is an essential component of a thorough examination of patents with shoulder dysfunction.
Fractures of the distal humerus or proximal ulna can alter the normal orientation of the articular surfaces of the humeroulnar articulation. Changes in the relative alignment of these surfaces can have a significant influence on the available ROM at the elbow following the fracture. Of course, stretching exercises cannot ameliorate motion restrictions due to bony malalignments
Clinical bottom line: Clinicians must distinguish between secondary to soft tissue limitations and those due to bony blocks
Rheumatoid arthritis frequently affects the glenohumeral joint, resulting in significant pain and disability. The large loads sustained by the humeral head during simple active ROM provide ample justification for the patient's complaints of pain. The benefits of exercise to maintain mobility and to increase strength must be weighed against the risks of increasing the joint loads and pain as well as perhaps hastening joint destruction. Active ROM activities performed in the supine position or in water decrease the moment generated by the weight of the upper extremity. Therefore, less muscle force is needed to move the shoulder. Consequently, the joint reaction force is smaller. The decrease in joint reaction force is one reason why patients with arthritis tolerate these exercises more readily.
Clinical bottom line: Clinicians must investigate joint positions and modes of exercise that minimize the risks to the joint while maximizing the physiological benefits.
Weakness of either the serratus anterior or the trapezius results in impaired function in both (Continued) flexion or abduction of the shoulder. Regardless of whether the serratus anterior, the trapezius, or both are weak, the weakness impairs the active motion of the scapulothoracic joint. Abnormal scapulothoracic joint rotation during shoulder elevation may contribute to impingement of the contents of the subacromial space. Consequently, a patient's complaints originating from weakness of the scapular rotators usually consist of complaints of weakness and difficulty reaching overhead but also may include complaints of pain when attempting overhead activities. Similarly, an evaluation of an individual with a shoulder impingement syndrome must include a careful assessment of the muscles that rotate the scapula upward. Su et al. assessed 20 competitive swimmers with complaints and signs consistent with subacromial impingement syndrome and matched 20 swimmers without complaints or signs of impingement. Scapular movements during shoulder elevation were similar in both groups prior to sim practice. However, after a hard practice, those swimmers with complaints exhibited significantly less upward rotation of the scapula. These data suggest the importance of active scapular control during repetitive shoulder elevation activities in protecting against impingement syndrome.
Clinical bottom line: Clinicians should carefully evaluate performance of the serratus anterior and trapezius muscles in any patient suffering from subacromial impingement syndrome.
Studies demonstrating the importance of rotator cuff activity in stabilizing the glenohumeral joint suggest that these muscles should be evaluated carefully in the presence of glenohumeral joint instability.
Clinical bottom line: Exercises to strengthen the rotator cuff muscles are an important element of the treatment of the unstable shoulder.
The brachial plexus and axillary blood vessels lie deep to the pectoralis minor muscle near its attachment to the coracoid process. Therefore, a stretch of a tightened pectoralis minor muscle can compress these sensitive structures and cause symptoms radiating distally into the upper extremity. Impingement of the brachial plexus or axillary blood vessels by a tight pectoralis minor muscle is one form of thoracic outlet syndrome (TOS). Neurological symptoms typically include tingling and perhaps numbness in the hand. Vascular symptoms may include blanching of the skin and a diminished pulse.
Clinical bottom line: Exercises to stretch the pectoralis minor muscle must proceed carefully to avoid exacerbating the symptoms.
Goniometry manuals describe measurement of medial rotation of the shoulder with the subject lying supine and the shoulder abducted to 90 degrees. In this position the shoulder is palpated to identify anterior tilting of the scapula as the shoulder is medially rotated.
Clinical bottom line: Firm manual stabilization is usually necessary to prevent the scapula from tilting anteriorly to substitute for medial rotation.
Inferior dislocations of the superior radioulnar joint most frequently occur in preschool children but are also reported in babies 6 to 12 months of age. The mechanism of injury is a tensile force directed distally on the forearm. Such a force may result as a baby, who is just developing rolling skills, attempts to extract the forearm from beneath the torso. More often, the force results from a pull on the forearm applied by an adult. Such a force occurs when swinging a child by the hands in play or when stopping a child from running into the street. Consequently , the injury is known as the "pulled elbow" or " nursemaid's elbow". The radial head is pulled through the ring of the annular ligament by the tensile force applied to the forearm. In young children, the annular ligament is weaker and more easily torn. In addition, it appears that the more narrow lateral aspect of the radial head slips out easily when the elbow is extended and the forearm pronated. Increased weight of the child is associated with a higher incidence of dislocation. The injury may also be more prevalent in children with hypermobility. As the child develops, the annular ligament becomes stronger as does the surrounding musculature. The injury rarely occurs after age six or seven
Clinical bottom line: Incidence of pulled elbow injury can be reduced by cautioning patents and other caregivers to avoid swinging or pulling young children by their hands.
Pain and tenderness in the levator scapulae, rhomboid major, and rhomboid minor are common clinical findings. Both weakness and tightness have been described as the explanation for pain along the medial aspect of the scapula and at its superior angle. At the present time, although there are widespread beliefs regarding the contributions of weakness and tightness to these complaints, there are no clear findings supporting or refuting these beliefs.
Clinical bottom line: It is essential that more precise means of assessing strength and tightness of these muscles become available.
The sternoclavicular joint is so well stabilized that fractures of the clavicle are considerably more common than dislocations of the sternoclavicular joint. In fact, the clavicle is the bone most commonly fractured in humans. Trauma to the sternoclavicular joint and clavicle most commonly occurs from forces applied to the upper extremity. Although clavicular fractures are commonly believed to occur from falls on an outstretched hand, a review of 122 cases of clavicular fractures reports that 94% of the clavicular fracture cases (115 patients) occurred by a direct blow to the shoulder. Falls on the shoulder are a common culprit. As an individual falls from a bicycle, for example, turning slightly to protect the face and head, the shoulder takes the brunt of the fall. The ground exerts a force on the lateral and superior aspect of the acromion and clavicle. This force pushes the clavicle medially and inferiorly. However, the sternoclavicular joint is firmly supported against such movements, so the ground reaction force tends to deform the clavicle. The first costal cartilage inferior to the clavicle is a barrier to deformation of the clavicle, and as a result, the clavicle is likely to fracture. Usually, the fracture occurs in the middle or lateral one third of the clavicle, the former more frequently than the latter. The exact mechanism of fracture is unclear. Some suggest that it is a fracture resulting from bending, while others suggest it is a direct compression fracture.
Clinical bottom line: Regardless of the mechanism, it is clear that fractures of the clavicle are more common than sternoclavicular joint dislocations, partially because of the firm stabilization provided by the disc and ligaments of the sternoclavicular joint.
The throwing motion puts a significant valgus stress on the elbow and consequently on the MCL. The repetitive stresses sustained by baseball pitchers from Little League players to Major League baseball pitchers can and frequently do lead to injuries to the MCL. When the injury includes tears of the MCL, surgical repair may be indicated. The most common, known as Tommy John surgery, named for the Major League pitcher whose career was saved by the surgery, reconstructs the torn MCL with a tendon, usually from the palmaris longus or the plantaris muscles, small muscles from the forearm or leg, respectively. The incidence of Tommy John surgery is increasing even among middle and high school athletes. Although the etiology of tears of the ulnar collateral ligament is not fully understood, the mechanics of thee throwing motion appears relevant.
Clinical bottom line: Rehabilitation experts can play a role in decreasing the incidence of UCL tears by working with parents, coaches, and athletes to optimize the throwing mechanics of the athlete. In the case of young pitchers, limiting the number of pitches allowed may also decrease the risk of injury.
Impingement syndrome is the cluster of signs and symptoms that result from chronic irritation of any or all of the structures in the subacromial space. Such irritation can come from repeated or sustained compression resulting from an intermittent or prolonged narrowing of the subacromial space. Symptoms of impingement are common in competitive swimmers and include pain midranges of shoulder elevation and worsening with increasing excursion of flexion or abduction. Most competitive swimming strokes require the shoulder to actively and repeatedly assume a position of shoulder abduction with medial rotation. This position narrows the subacromial space and consequently increases the risk of impingement.
Clinical bottom line: Some clinicians and coaches suggest that to prevent impingement, swimmers shoulder perform strength and endurance exercises for their scapular muscles so that scapular position can enhance the subacromial space even as the humeral position tends to narrow it.
The rotator cuff muscles seem to be particularly susceptible to fatigue and overuse, especially in middle-aged adults. Thus, it is not surprising to see middle-aged patients who report a history of acute onset of shoulder pain following unusual and prolonged overhead activity such as three sets of tennis at the beginning of the tennis season or an afternoon of window washing. A likely scenario to explain the complaints is (a) prolonged overhead activity, (b) fatigue of the rotator cuff muscles, (c) inadequate stabilization of the humeral head, and (d) superior glide of the humerus causing compression of the contents of the subacromial space, including the subacromial bursa and supraspinatus tendon, with (e) resulting bursitis or tendonitis.
Clinical bottom line: Successful treatment of the patient's complaints must include interventions to reduce inflammation of the bursa or tendon. These interventions include medication, rest, and ice. However, treatment should also address the underlying pathomechanics, with particular focus on strength and endurance training for the rotator cuff muscles. Patient education explaining the relationship between fatigue and pathomechanics also may help the patient avoid a recurrence.
When making judgments about the quality of a patient's ROM, the clinician must remember the possibility of large intersubject differences. The differences between an individual's right and left sides may be more important than the difference between an individual's ROM and the "normal" value found in the literature
Clinical bottom line: The clinician must evaluate the uninvolved side to help establish the patient's "normal" excursion
The standard position to perform manual muscle testing ( MMT) of the pronators of the forearm is with the elbow partly flexed. However, to assess the strength of the pronator quadratus alone, the elbow is flexed maximally. This position puts the pronator teres in a very shortened position and alters the muscle's moment arm. Thus, although the muscle remains electrically active, the elbow position shortens the proctor teres enough that it can no longer effectively generate a pronatio force. The pronator teres apparently exhibits active insufficiency as described earlier in the biceps brachii with shoulder and elbow flexion. The force of pronation with the elbow maximally flexed presumably comes from the pronator quadratus muscle. However, additional research is needed to clearly understand the unique contributions of both the pronator teres and pronator quadratus muscles.
Clinical bottom line: The clinician must recognize that elbow and forearm positions are likely to strongly affect the contributions of the pronator teres to pronation force. Although these contributions may not be fully understood at this point, care is needed to standardize strength testing procedures to at least keep these effects constant.
Shoulder impingement syndrome is the most common source of shoulder complaints, and the complicated and finely coordinated mechanics of the shoulder complex help explain the frequency of complaints. Ealier clinical relevance boxes demonstrate the possible contributions to impingement syndromes from dysfunction within individual components of the shoulder complex, such as abnormal axial rotation of the humerus or abnormal scapular positions. Abnormal scapulohumeral rhythm during shoulder flexion or abduction is also associated with impingement syndromes, although it is unclear whether the abnormal rhythm is a cause or an effect of the impingement.
Clinical bottom line: The multiple mechanical dysfunctions that can lead to symptoms of impingement demonstrate the importance of understanding the normal mechanical behavior of each individual component of the shoulder complex as well as the behavior of the complex as a whole. WIth such an understanding, the clinician will be able to thoroughly and accurately evaluate the movements and alignments of the individual parts of the shoulder as well as the coordinated function of the entire complex in order to develop a sound strategy for intervention.
The proposed function of the supraspinatus in preventing the inferior subluxation of the glenohumeral joint is facilitated by upward rotation of the glenoid fossa. Thus, weakness of the muscles that stabilize the scapula may contribute to inferior subluxations of the joint. Such inferior subluxations of the shoulder are frequently found in patients with diffuse upper extremity weakness following stroke. Weakness of the trapezius is reportedly characterized by depression of the acromion process demonstrating downward rotation of the scapula. Thus, the inferior subluxation of the glenohumeral joint may be the result of the combined effects of weakness of the supraspinatus and trapezius muscles. Splints that provide an upward force on the humerus to stabilize an inferiorly subluxed glenohumeral joint are generally unsuccessful in reducing subluxation. Current treatment approaches include exercises to restore upward rotation of the glenoid fossa while facilitating the activity of the rotator cuff muscles. Additional study is required to clarify the mechanism of inferior subluxation and to optimize treatment.
Clinical bottom line: The position of the scapula should be considered when developing strategies to stabilize the glenohumeral joint.
When an individual falls on an outstretched hand, the radius sustains large axial loads that could be transmitted directly to the distal humerus. However, the orientation of the interosseous membrane allows it to disperse some of the load to the ulna, thus decreasing the load directed onto the capitulum. The load on the radius tends to push it proximally into the humerus. However, as the radius tends to move proximally, the interosseous membrane pulls the ulna proximally as well, thus distributing the axial load to the ulna and ultimately to the trochlea. Consequently, the load is spread over a larger area of the humerus, and the stress ( force/ area) is decreased, perhaps decreasing the risk of fracture.
Clinical bottom line: Ulnar head resection at the wrist as a result of severe arthritis or fracture diminishes the load sharing ability of the ulna when loads are applied through the hand. Ths may lead to elbow pathology in addition to the original pathology at the wrist.
Dislocation of the AC joint is a common sports injury, especially in contact sports such as football and rugby. The mechanism is similar to that of clavicular fractures, a blow to or fall on the shoulder. Because of the strength of the coracoclavicular ligament, dislocation of the AC joint often occurs with a fracture of the coracoid process (type III dislocation) instead of a disruption of the ligament itself.
Clinical bottom line: When examining an individual with a suspected AC joint dislocation, appropriate measures should be taken to determine if there is a concomitant fracture of the clavicle and/or coracoid process.
In adhesive capsulitis, fibrous adhesions form in the glenohumeral joint capsule. The capsule then is unable to unfold to allow full flexion or abduction, resulting in decreased glenohumeral joint excursion. Adhesive capsulitis can be classified as idiopathic (insidious onset) or secondary (i.e., related to thyroid disease, diabetes mellitus, proximal humeral fracture).
Clinical bottom line: With either idiopathic or secondary adhesive capsulitis, the classic physical findings are severe and painful limitations in joint ROM. Often, patients complain of periscapular muscle pain due to overuse of these muscles in an attempt to increase shoulder complex motion through excessive scapulothoracic movements.
Olecranon fractures can occur from an aggressive pull of the triceps causing an avulsion fracture or from a direct blow to the tip of the olecranon. In vitro experiments with 40 cadaver limbs reveal that olecranon fractures through the deepest part of the trochlear notch are easily produced by direct impacts to the proximal olecranon. The average impact producing the fracture is 4, 100 N. such an impact simulates a fall onto the tip of the elbow. It is significant that the fractures occur in the deepest part of the trochlear notch where there is less mineralization in the subchondral bone
Clinical bottom line: an awareness of the bony architecture of the elbow helps explain a common injury
Although the clinician can rarely alther a muscle's moment arm, the moment arm of the resistance is easily manipulated. Resiman report an almost 100% increase in internal moment in subjects ambulating with axillary crutches when the crutch handle is raised 1 to 2 inches from its optimal height this remarkable increase in the muscles' requirements is the result of increased elbow flexion and consequently, an increase in the moment arm of the resistance. Similar changes in joint loads are reported in exercises such as the push-up and bench press
Clinical bottom line: an understanding of joint moments can guide the clinician in altering the requirements of a joints muscles and the load on a patient's joint by altering the moment applied by the external load
Normal elbow flexion range has a characteristic soft end- feel resulting from the contact of the forearm muscles against the relaxed elbow flexors. Elbow extension has a springier end feel, suggesting limits from the ligaments and stretch of the elbow flexors. Bony contact is sometimes reported as the limiting factor in elbow extension. However nerve blocks to the elbow flexors in healthy individuals have resulted in increased extension ROM, suggesting that muscles provide the initial limits to normal elbow extension ROM in most individuals. It is important to recall the wide range of variability within the healthy population, as suggested by the standard deviations presented in table 11.1. Perhaps individuals with little muscle mass and generalized hypermobility do have bony limitations in elbow ROM, particularly extension.
Clinical bottom line: assessment of end-feel can help determine the structures responsible for stopping the joint motion
Compensations for restricted elbow ROM during functional activities include increased shoulder motions. Shoulder pain can then develop in patients with limited elbow mobility, as a result of overuse of the shoulder.
Clinical bottom line: clinicians must carefully assess the shoulder in patients with elbow dysfunction. Conversely, the elbow should be screened in patients with shoulder complaints.
Clinicians affect a patient's elbow flexion strength by varying the position of the elbow or shoulder joint. To correctly identify a change in strength as the result of intervention or disease, a clinician must standardize the position of both the shoulder and the elbow when testing elbow strength. On the other hand, shoulder hyperextension is a useful position in which to exercise a patient with weakness of the biceps brachii, since the resulting muscle stretch enhances the muscle's force output.
Clinical bottom line: clinicians must consider shoulder position whenever testing or treating the function of the biceps brachii
It has long been suggested that the incidence of tendon pathology in the long head of the biceps is increased in individuals with rotator cuff pathology. A study of inflammatory biomarkers suggests that degenerative changes in the long head of the biceps are secondary to rotator cuff tears. The changes in the biceps are likely the result of overload as the muscle attempts to increase shoulder stability in the absence of rotator cuff competence
Clinical bottom line: clinicians must recognize the potential for biceps pathology in patients with rotator cuff pathology. Perhaps early strengthening exercises for the biceps can help mitigate the effects of overload.
An elbow flexion contracture is the loss of full passive elbow extension ROM. this may be the result of tightness of the anterior joint capsule and collateral ligaments or of one or all of the elbow flexor muscles. Appropriate treatment to reduce the contracture requires correct identification of the offending structure. Identification of tightness of the biceps brachii muscle is based on an understanding of its actions at both the elbow and the shoulder joints and the clinician's ability to manipulate the muscle length by changing the position of the shoulder and elbow. If the elbow joint capsuloligamentous complex is tight, elbow joint ROM is restricted, regardless of shoulder and forearm position. However, if the biceps brachii is tight and limiting elbow joint extension ROM, flexion of the shoulder joint puts the muscle in a slackened position that can allow an increase in elbow joint extension ROM. similarly pronation of the forearm stretches the biceps brachii and may decrease the elbow extension ROM available. The biceps brachii muscle is maximally stretched by shoulder extension combined with elbow extension and forearm pronation.. It is maximally shortened by shoulder and forearm pronation. It is maximally shortened by shoulder and elbow flexion with forearm supination
Clinical bottom line: combinations of shoulder and elbow positions can be used to identify any contribution from the biceps brachii to an elbow flexion contracture
Removal of the radial head, or radial head excision, is a surgical procedure considered in the presence of a radial head fracture or severe arthritic changes. Some studies suggest there may be little increase in joint laxity as a result, while others report more significant instability. There appear to be few functional deficits as a result. Elbow instability after radial head resection may indicate more extensive soft tissue damage,
Clinical bottom line: injuries involving both the radial head and MCL ligament frequently require extensive surgical intervention, and the functional consequences are more severe.
Nerves are most susceptible to injury in locations where they lie against rigid structures or in rigid spaces. The radial nerve is particularly vulnerable as it travels along the humerus in the radial (spiral) groove. Similarly, the ulnar nerve is at risk as it wraps around the medial epicondyle at the elbow. Few individuals have escaped the characteristic pain and tingling that radiate distally through the medial aspect of the forearm and hand when the medial aspect of the elbow (the crazy bone) hits a door or piece of furniture. More serious and lasting injuries to the ulnar nerve also occur as the nerve travels through the restricted space of the cubital tunnel. Preliminary studies suggest that the cubital tunnel narrows during elbow flexion as a result of a stretch to the fascial covering. This narrowing apparently is accompanied by a stretch to the nerve itself.
Clinical bottom line: the combination of cubital tunnel narrowing and nerve stretch may contribute to some ulnar nerve neuropathies at the elbow
Individuals with tetraplegia at the level of C6 lack active control of the triceps brachii, innervated at the level of C7 and C8. yet these individuals generally have control of the elbow flexors and the shoulder muscles. This remaining motor control allows most to perform independent sliding transfers such as to and from wheelchairs. Despite the absence of elbow extension strength, the elbow extension strength, the individual is able to bear weight on the upper extremity by locking the elbow in extension. The elbow can be maintained in extension passively by placing the elbow in hyperextension and supporting it by the bones and ligaments of the joint or by keeping the weight of the head and trunk posterior to the elbow joint, thereby creating an extension moment at the joint. However, the presence of a flexion contracture prevents the individual from supporting the elbow passively by locking the elbow and may compromise function. Grover demonstrates that an elbow flexion contraction of approximately 25 degrees prevents a patient with C6 tetraplegia and complete loss of triceps brachii strength from performing a sliding transfer
Clinical bottom line: the prevention of elbow flexion contractures is an essential element in the goal of independent function for individuals with C6 tetraplegia
External valgus moments ( frontal plane moments tending to rotate the elbow into valgus) of approximately 18 Nm are reported in 11- and 12 year old male pitchers. Professional baseball pitchers reportedly sustain valgus moments of approximately 65 Nm . contrast these moments that are balanced by the elbow's medial collateral ligament with perhaps additional support from forearm muscles with the flexion moment of 28 Nm balanced by the elbow extensor muscles during crutch walking. It should not be a surprise that elbow injuries are common in baseball pitchers
Clinical bottom line: with the increased incidence of ulnar collateral ligament injuries in young athletes, it is incumbent upon clinicians to understand the loads placed on the ligament and to look for strategies to decrease those loads.
Patients with inflammation of the elbow joint frequently find that the position of comfort is significant elbow flexion. This clinical finding is consistent with the evidence suggesting that the tension in the joint capsule is minimized with the elbow flexed to 80 degrees. It is likely that patients seek a position that minimizes the tension on the joint capsule, thus relieving pain associated with a stretch of the capsular ligament. However, prolonged positioning in flexion in the presence of inflammation may result in adaptive changes in the surrounding musculature as well as structural changes in the capsule itself, resulting in a flexion contracture.
Clinical bottom line:Treatment to reduce elbow joint inflammation is critical to maintaining joint function. As long as the joint inflammation continues, the patient must be instructed to avoid prolonged flexion positions to prevent a flexion contracture.
Standard manual muscle testing procedures for the supinator muscle are described with eh elbow extended and with the elbow and shoulder flexed. EMG data and an understanding of the mechanics of muscle action demonstrate the theories underlying these two positions. EMG data suggest that with the elbow extended, the biceps brachii is inhibited. Its contribution to supination strength also may be reduced because of its decreased supination moment arm in elbow extension. Therefore, supination in that position presumably results from activity of the supinator muscle. However, aggressively resisted supination with the elbow extended does appear to elicit biceps brachii activity, usually resulting in some elbow flexion. Since MMT is designed to resist the patient maximally, it is likely that the biceps is recruited in this test, at least in the phase when maximum resistance is applied On the other hand, the MMT position with the elbow and shoulder flexed is likely to recruit both the supinator and biceps brachii muscles. However, in this position, the biceps brachii is shortened almost maximally. As noted earlier in this chapter an in detail in chapter 4, shortening a muscle reduces its contractile force. Therefore, although the biceps brachii is most likely active during this MMT of supination, the force that it can generate in supination is greatly reduced, and the force of supination measured is primarily the force of the supinator muscle
Clinical bottom line:it is important for the clinician to recognize that either test may be suitable under certain circumstances. However, it is essential to keep in mind the factors influencing the results of each test
Subscapularis Weakness:
Decreased activation of the subscapularis is reported in some individuals who can sublux their glenohumeral joints spontaneously using lateral rotation. Muscle re-education to facilitate the subscapularis and other medial rotators is an important component of the rehabilitation program to increase stability.
Humeroulnar Dislocations
Dislocations of the humeroulnar articulations can occur posteriorly where there is little bony limitation to the trochlear notch being pushed off the trochlea. More frequently, dislocations occur in a combination of lateral and posterior movement of the forearm resulting from a force directed laterally on the distal forearm. Such dislocations are usually accompanied by tears of the supporting ligaments, described below.
Manual Muscle Testing of the Lower Trapezius:
In the prone position with the shoulder flexed, the weight of the upper extremity tends to pull the scapula into elevation and abduction. Consequently, the lower trapezius functions to offset this motion by pulling the scapula into depression and adduction, thereby stabilizing the scapula on the thorax. Thus, the resistance in the "Fair" test of the lower trapezius is the weight of the upper extremity.
Scapular Winging Due to Serratus Anterior Weakness:
Medial winging of the scapula during activities that require shoulder elevation is a classic sign of weakness of the serratus anterior muscle. In contrast, winging of the scapula at rest or during passive motion of the shoulder can be a sign of restricted ROM at the glenohumeral joint or postural abnormalities. For example, as described in the previous chapter, anterior tilting of the scapula is an effective substitute for inadequate medial rotation of the glenohumeral joint. The position of the scapula when it is tilted anteriorly is similar to that seen with serratus anterior weakness. However, in the case of glenohumeral joint restriction, the prominence of the scapula occurs during activities such as reaching into a back pocket, when minimal serratus anterior activity is required. Thus, the scapular prominence in this case is much less likely to be the result of serratus anterior muscle weakness. This is a critical distinction for the clinician to make.
Radical Mastectomy, A Case Report:
Surgical procedures for the treatment of breast cancer include removal of breast tissue and sometimes underlying musculature. The radical mastectomy, rarely performed any longer, involved the removal of all or part of the pectoralis major. Although weakness was demonstrated following surgery, in some individuals, surprisingly little dysfunction followed. A 62 year old female had undergone bilateral radical mastectomies and total resection of the pectoralis major muscle bilaterally in the 1960's. Yet 10 years later, she was the reigning female champion of her local tennis club. The absence of profound loss of function is consistent with the fact that the pectoralis major provides additional strength to the shoulder but no additional motional that are not available from contractions of other muscles.
Osteoarthritis of the Acromioclavicular Joint:
The AC joint is a common site of osteoarthritis particularly in individuals who have a history of heavy labor or athletic activities. The normal mobility of the joint helps explain why pain and lost mobility in it from arthritic changes can produce significant loss of shoulder mobility and function.
Asymmetrical tonic neck reflex (ATNR) in a child with a developmental disorder
The ATNR is a normally occurring motor reflex in infants. The reflex is manifested in the upper extremities by a change in muscle tone in each upper extremities, determined by the rotation of the head and neck. As the head is turned to one side, there is a increase in motor tone in the extensor muscles of the upper extremity to which the head is turned. There Is a concomitant increase in flexor tone in the opposite extremity. Increased muscle tone in the extensor muscles creates an increased resistance to flexion. This reflex usually is integrated as normal motor development unfolds during the first year, before the child can perform many independent activities of daily living. However, in some children with developmental delays and impaired motor control, the reflex may continue to be evident even as the child becomes ready for some functional independence. In this case, the abnormal presence of an ATNR may interfere with the child's ability to gain independence in activities such as self feeding. As the child looks at the hand with the food in it, the extensor tone increases in that limb, increasing the difficulty of flexing the elbow and bringing the food to the mouth.
Identifying individual weakness in the elbow flexors
The EMG data for the elbow flexor muscles reveal that no single motion isolates any of the elbow flexors. Consequently, identification of weakness in an individual elbow flexor muscle requires measurement of elbow flexion strength in several forearm positions combined with careful palpation. Isolated weakness of the biceps affects elbow flexion strength most when the forearm is supinated or in neutral and to a lesser degree with forearm pronation. In contrast, weakness of the brachioradialis has little effect on elbow flexion strength with the forearm supinated but a larger effect when the forearm is pronated maximally. Isolated weakness of the brachialis causes decreased elbow strength in all forearm positions. However, it may be most evident when the forearm is pronated, since, in this position , the biceps has a smaller role and consequently provides less compensation for brahialis weakness. Measurement of supination strength with the elbow flexed and extended also helps to identify weakness of the biceps brachii
The Depth of the Bicipital Groove:
The depth of the bicipital groove varies. A shallow groove appears to be a contributing factor in dislocations of the biceps tendon.
Manual Muscle Test of the Sternal Portion of the Pectoralis Major:
The standard position for the subject during manual muscle testing of the sternal portion of the pectoralis major is supine with the shoulder flexed. In this position, the weight of the upper extremity tends to keep the shoulder flexed, that is, the weight creates a flexion moment at the shoulder. Therefore, the muscle must create an extensor moment to counteract the weight of the upper extremity. The sternal portion of the pectoralis major is recruited as the subject attempts to return the upper extremity to the neutral position.
Upper Extremity Weight Bearing:
Upper extremity weight bearing is extremely important in rehabilitation and also in athletic events. An individual who uses a wheelchair must lift himself off the seat to relieve pressure on the buttocks or to transfer to another seat. Without the use of the lower limbs, such as occurs following some spinal cord injuries, the individual lifts almost the entire weight of the body with the upper extremities, pushing down with the hands. The wheelchair exerts a reaction force on the upper extremities in an upward direction. This force tends to elevate the shoulders; therefore, the shoulder depressor muscles are required to "depress" the shoulder, or, more accurately, "fix" the shoulder, preventing it from being elevated by the reaction force. By stabilizing the shoulder girdle, the shoulder depressor muscles allow the upward chair reaction force to be transmitted to the rest of the body to lift it from the chair. Similarly, a gymnast supports the weight of the body through the upper extremities during many gymnastic movements. In both cases, the pectoralis major and latissimus dorsi muscles are the primary muscles lifting the body weight by "depressing the shoulder". These two muscles can be assisted by additional shoulder depressors, including the pectoralis minor and subclavius muscles.
Spinal Accessory Nerve Injury:
Weakness of any or all of the trapezius can result from an injury to the spinal accessory nerve, which lies superficially in the posterior triangle of the neck, formed by the anterior border of the upper trapezius muscle, the posterolateral border of the sternocleidomastoid muscle, and the middle third of the clavicle. The nerve can be injured during neck surgery, such as a lymph node biopsy, or by a blow or laceration to the top of the shoulder. A patient with a spinal accessory nerve palsy typically reports weakness in activities overhead. The individual's posture may be characterized by a drooping shoulder and the scapula may be pulled into abduction. The abducted position of the scapula is accentuated during active shoulder abduction and is sometimes known as lateral winging. Assessment of shoulder strength reveals decreased strength in shoulder elevation, particularly in shoulder abduction as well as in weakness in the discrete movements of the scapula attributable to the trapezius.
A 20 yo male received multiple injuries after being hit by a truck. Included in the injuries was a mid humeral fracture with radial nerve palsy distal to the innervation of the triceps brachii. Treatment focused on restoring strength to the wrist and finger extensor muscles. The subject was reassessed 1 year after the accident. At the time of reassessment, the subject noted considerable recovery in hand strength and no apparent difficulty at the elbow. Examination of the elbow revealed normal ROM and strength of the elbow flexors and extensors. Examination also revealed that supination strength with the elbow flexed to 90 degrees was slightly reduced. However, supination with the elbow extended was markedly reduced. The subject was unable to supinate through the full supination ROM. any additional resistance against supination with the elbow extended resulted in elbow flexion. These results revealed weakness of the supinator muscle that had gone undetected in previous examinations.
case report
