Valgus Instability
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Valgus instability is due to attenuation or rupture of the anterior bundle of the medial collateral ligament.
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Symptomatic medial collateral ligament injury is almost exclusively a problem of throwing athletes (e.g., pitchers or javelin throwers).
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Athletes usually present with the gradual onset of pain while throwing or an inability to throw with great force or velocity, although acute rupture of the ligament occasionally occurs.
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Due to the repetitive valgus stress of throwing, other medial elbow complaints may occur simultaneously, including medial epicondylitis, ulnar nerve irritation, and posteromedial elbow pain due to osteophyte impingement (valgus extension overload syndrome).
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Physical examination seldom reveals obvious gapping or instability, but relies on the reproduction of pain during a variety of valgus stress maneuvers.
Posterolateral Rotatory Instability
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Posterolateral rotatory instability is due to attenuation or rupture of the lateral ulnar collateral ligament.
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Posterolateral rotatory instability is usually a late result of elbow dislocation or subluxation.
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Iatrogenic injury to the lateral ligament complex, which usually occurs during surgery for lateral epicondylitis or radial head fracture, is another cause of posterolateral rotatory instability.
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Although patients may suffer recurrent dislocation or obvious subluxation, symptoms are often much more subtle, including pain, snapping, clunking, or locking, particularly when the elbow is placed in extension and supination.
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Frank instability or subluxation can rarely be reproduced during physical examination, except under anesthesia; however, apprehension and pain during extension and supination stress to the elbow are suggestive.
A relatively limited number of symptoms prompt a patient with elbow dysfunction to seek medical attention. The most commonly voiced complaint is elbow pain that may arise from the joint itself or from any of the myriad surrounding soft tissues. Although pain in or around a joint is usually the result of arthrosis, inflammation, or trauma of some sort, other, more subtle diagnostic possibilities must not be overlooked, including those of neurologic, metabolic, neoplastic, and even congenital origin. Complications related to prior surgical treatment or failed attempts at fracture fixation, specifically infection, nonunion, or malunion, may also be causes of pain.
Limitation of motion is the next most common elbow complaint. The elbow has the greatest functional range of motion of any joint in the upper extremity, and it has a great propensity for capsular contracture following even minor trauma or brief periods of immobilization. The unfortunate association of these two circumstances in a single joint makes loss of elbow motion a significant problem.
Instability of the elbow is encountered much less frequently than either pain or loss of motion, and for this reason it has only recently begun to be more clearly understood. Instability can be the result of a single traumatic event, such as dislocation, often accompanied by fracture and, in these circumstances, may even rarely manifest as recurrent dislocation. Although it seems counterintuitive, instability after major trauma to the elbow may cause significant pain, leading to stiffness and joint contracture. Instability may also result from chronic attritional injury to ligamentous structures as seen, for example, in throwing athletes. Patients with elbow instability often do not appreciate “giving way,” “clunking,” or other more obvious mechanical symptoms, but instead complain that they cannot use their elbows with force in certain positions or cannot perform certain activities with the power to which they are accustomed.
Weakness associated with attempted use of the elbow may accompany other presenting symptoms. In the absence of more proximal neurologic injury, this complaint is usually the result of an underlying painful process causing reflex inhibition or instability leading to apprehension.
History
Examination of the elbow begins with a thorough history of the presenting complaint. If a specific traumatic episode has occurred, an attempt should be made to define the mechanism of injury as accurately as possible. Such information often suggests subtle diagnoses or patterns of injury that may involve anatomic areas other than the elbow itself. In the absence of a specific traumatic event, it is often helpful to inquire about any new or different activities that the patient had engaged in during the days and weeks preceding the onset of symptoms.
It is best to allow patients a minute or two at the beginning of the interview to explain matters in their own words; they may provide information that we would not think to ask about. Careful questioning then leads to establishing a list of differential diagnostic possibilities, which can guide the physical examination. Table 8-1 contains recommended questions to ask your patient during the history. Especially when visiting a specialist, patients often neglect to volunteer information that they believe is unrelated to the current problem. Associated complaints, including involvement of other joints, fever, malaise, and related constitutional symptoms, should be specifically sought. An accurate understanding of the general medical history is another important prerequisite for appropriate diagnosis and treatment.
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We should endeavor to understand not only the constellation of elbow symptoms that prompts the patient’s visit, but also, and perhaps more importantly, how these symptoms interfere with vocational and avocational function. Dynamic elbow instability may incapacitate an athlete, interfering with his or her livelihood, whereas it is often a minor annoyance that can be managed symptomatically in an older, more sedentary individual. Relatively minor joint contracture that might not even be considered for treatment in the average individual may occasionally prove disabling for certain musicians or skilled craftsmen.
When obtaining a history from an athlete with elbow complaints, detailed knowledge of the specific sport or activity can be of great benefit. For example, throwing athletes with ulnar collateral ligament insufficiency or other medial elbow disorders experience symptoms during the late cocking and acceleration phases of the throwing motion, whereas those with posterior elbow pathology more often complain of pain during deceleration and follow-through. , Pitching style, innings pitched, average pitch count, and even the timing of the appearance of symptoms during training or seasonal play may all be important variables to consider.
An understanding of the response to previous treatment is helpful in both establishing a diagnosis and making plans for further efforts. The details of surgical procedures are appreciated most clearly after reviewing the operative record. Such documentation may provide an invaluable firsthand description of the status of articular surfaces or supporting soft tissue structures. It is particularly helpful to know how the ulnar nerve has been handled during previous surgery: Has the nerve been transposed anteriorly? Is it subcutaneous or submuscular? Occasionally, it may be helpful to speak directly with prior caregivers if adequate records are unavailable.
Physical Examination
In our zeal to determine the cause of elbow pain we must not focus so narrowly on the elbow that we miss other associated or causative pathologic conditions. Injury around the elbow may be associated with fracture or dislocation throughout the length of the linked bones of the forearm, particularly the distal radioulnar joint. An obvious fracture with significant deformity at the level of the elbow may draw our attention away from a more subtle, unrelated injury elsewhere in the limb. In athletes, shoulder dysfunction may alter throwing mechanics, resulting in secondary elbow pathology. It is imperative that the entire upper extremity be examined. Radiculopathy may occasionally manifest as elbow pain, necessitating careful examination of the cervical spine.
It is helpful to have access to the entire upper limb, including the shoulder, during examination of the elbow. Access to a standard orthopedic examination table may be necessary, as certain maneuvers, especially when evaluating elbow instability, may be more easily performed with the patient supine. It is advisable, especially for the novice, to establish a “routine” examination that can be performed the same way each time. This helps to ensure that components of the examination are not omitted and makes follow-up more consistent and reliable. Normal or asymptomatic areas should be examined first, saving those areas that may be uncomfortable for the conclusion of the examination. Subtle or questionable findings may be confirmed by reference to the contralateral, presumably normal, extremity. Examination of the asymptomatic elbow first may help to relieve patient anxiety, making it more likely that subtle findings are elicited, particularly when evaluating elbow instability.
All three of the major nerves in the upper extremity pass in close proximity to the elbow joint and can be injured or functionally impaired by elbow pathology. Careful documentation of neurologic function is necessary before any treatment is rendered. Supracondylar fractures of the humerus and, occasionally, elbow dislocation can result in critical vascular compression or disruption. In certain individuals, collateral arterial flow is insufficient, and injury to the brachial artery results in dysvascularity of the distal extremity. Failure to promptly recognize such injury can result in devastating consequences, such as compartment syndrome, secondary ischemic contracture, or loss of limb.
Inspection
Any physical examination begins with careful observation. Obvious signs of trauma, including edema, ecchymosis, or cutaneous injury, are noted. In all but the most obese individuals, the bony prominences of the medial humeral epicondyle and tip of the olecranon are apparent unless masked by overlying edema. The most obvious swelling to occur around the elbow is associated with olecranon bursitis, which may be either inflammatory or infectious in origin.
Occasionally, the ulnar nerve or medial triceps muscle can be seen to snap over the medial epicondyle during active range of motion (ROM), although this finding is usually more apparent during palpation of the medial elbow. The lateral humeral epicondyle may be visible in very thin individuals. There is normally a depression, the infracondylar recess, just distal and posterior to the lateral epicondyle, although it can sometimes only be appreciated by palpation. Hemarthrosis, joint effusion, or synovial proliferation may obliterate the recess, causing a visible bulge or swelling in this area. , Muscular atrophy or hypertrophy may be appreciated by comparison with the contralateral extremity; athletes may exhibit significant hypertrophy in their dominant arms.
The integrity and adequacy of the soft tissue envelope should be noted. The location of wounds; healed surgical incisions; and scarred, adherent, or atrophic skin resulting from previous injury must be documented carefully. Cutaneous scarring owing to thermal burns often causes significant joint contracture. Poor-quality soft tissue surrounding this superficial joint may influence available management options or may have to be addressed as part of the treatment plan, particularly if surgery is contemplated.
The carrying angle of the elbow is evaluated with the joint in full extension and the forearm in full supination. Although measures vary greatly, the normal elbow is in modest valgus, which has been reported to average 11 to 14 degrees in males and 13 to 16 degrees in females. The carrying angle may be 10 to 15 degrees greater in the dominant arm of throwing athletes due to adaptive remodeling of the bone as a result of repetitive stress. This angle can be difficult to evaluate in the face of a flexion contracture, because the carrying angle normally changes gradually from valgus to varus as the elbow is flexed.
Alteration of the carrying angle may be caused by malunion of fractures around the elbow or a growth disturbance resulting from childhood injury to the physeal mechanism. Cubitus varus is caused by a reversal of the normal valgus carrying angle and, when significant, is termed a gunstock deformity. Cubitus valgus is used to describe an exaggeration of the normal valgus carrying angle. This deformity may cause a traction neuropathy of the ulnar nerve, resulting over many years in what has been termed tardy ulnar nerve palsy .
Palpation
Because the elbow is relatively superficial, deliberate and systematic palpation performed with an appreciation of the underlying anatomy can yield significant diagnostic information. The major osseous landmarks around the elbow are directly palpable beneath the subcutaneous tissue.
Posterior
When viewed from behind, the tips of the medial epicondyle, lateral epicondyle, and olecranon form an isosceles triangle when the elbow is flexed; in full extension, these three landmarks are collinear ( Fig. 8-1 , online). In the event of supracondylar fracture of the humerus, this triangular configuration is maintained, although its relationship to the proximal humerus will be altered. Disruption of the symmetry of the triangle indicates that the relationship between the olecranon and the epicondyles has been altered, suggesting ulnohumeral dislocation or distal humeral growth disturbance.
Tenderness, thickening, and fluctuance over the tip of the olecranon are indicative of olecranon bursitis . These findings occasionally may be associated with a bony prominence at the tip of the bone or with fibrinous free-floating bodies within the bursa. Infectious bursitis may present with marked increased warmth, tenderness, and blanching of the skin.
The broad insertion of the triceps can be palpated and defects recognized in cases of rupture of this tendon, although local swelling and hemorrhage may make this difficult following acute injury. The posteromedial olecranon is a common site of tenderness, local articular cartilage injury, and osteophyte formation in throwing athletes (see subsequent section on Specific Diagnostic Maneuvers). Pain to palpation directly over the tip of the olecranon in an adolescent may be caused by apophysitis .
Osteophyte formation on the most proximal extent of the olecranon is commonly seen in cases of primary osteoarthritis. In thin individuals, tenderness in this area can be appreciated during deep palpation in the region of the olecranon fossa with the elbow flexed to approximately 30 degrees. In full extension, the proximal olecranon is contained within the olecranon fossa of the humerus and cannot be palpated; with elbow flexion beyond 30 degrees, the triceps becomes increasingly taut, prohibiting palpation of the proximal olecranon.
Lateral
The lateral supracondylar ridge of the humerus can be palpated, terminating at the prominence of the lateral epicondyle. Snapping of the lateral aspect of the triceps tendon over the epicondyle as the elbow is flexed has been described as a rare source of elbow symptoms. Just distal and slightly posterior to the lateral epicondyle, a quadrant of the radial head can be felt, veiled only by the anconeus muscle and subjacent capsuloligamentous structures. As the forearm is rotated, the margin of the radial head passes beneath the examiner’s fingers ( Fig. 8-2 ). The lateral ligaments are located beneath the overlying musculature, and cannot be palpated directly. Disruption or incompetence of the lateral ligaments is seldom associated with local tenderness to palpation, except in the acute stage immediately following injury.
The infracondylar recess, located in the triangular area bounded by the lateral epicondyle, the radial head, and the tip of the olecranon, contains the most superficial and easily palpable extent of the elbow joint capsule. The earliest signs of hemarthrosis, synovitis, or joint effusion may be appreciated here. This is also the preferred location for performing arthrocentesis of the elbow ( Fig. 8-3 , online).
The brachioradialis and extensor carpi radialis longus originate on the anterior edge of the lateral supracondylar ridge and are most easily appreciated when elbow flexion and wrist extension are resisted. These muscles, along with extensor carpi radialis brevis, whose origin lies deep to that of the longus, have been described by Henry as the “mobile wad of three,” in recognition of the fact that they can be grasped and moved relative to the other musculature originating from the lateral epicondyle at the common extensor origin. The most proximal extent of brachioradialis may be 8 cm or more proximal to the tip of the lateral epicondyle (see Fig. 8-2 ).
The degenerative process known as lateral epicondylitis (or colloquially, tennis elbow ) most commonly involves the origin of the extensor carpi radialis brevis. In these cases, pain on palpation is located just distal or adjacent to the tip of the lateral epicondyle, and symptoms are exacerbated by resisted wrist extension, particularly when the elbow is fully extended, thereby placing the muscle on maximum stretch. Repeated corticosteroid injections utilized in the treatment of this disorder may result in dimpling of the overlying soft tissue due to subcutaneous fat atrophy and local skin depigmentation.
Although it lies deep to the overlying musculature and cannot be directly palpated, the posterior interosseous nerve is most easily appreciated 4 to 5 cm distal to the lateral epicondyle as it courses around the proximal radius in the substance of the supinator muscle (see Fig. 8-2 ). Local tenderness in this area, not directly adjacent to the epicondyle, helps to distinguish posterior interosseous compression neuropathy from lateral epicondylitis, although the two may sometimes coexist. Motor palsy involving the digital extensors may result from compression of the nerve in this area, usually due to mass effect or local trauma. More commonly, entrapment of the posterior interosseous nerve in the proximal forearm presents as deep aching pain, sometimes with radiation to the wrist, and is known as radial tunnel syndrome.
Anterior
The anterior aspect of the elbow or cubital fossa is a triangular area bounded medially by pronator teres and laterally by brachioradialis. The median nerve , as its name implies, is the most medial structure in the fossa. Unusual tenderness to palpation of the nerve in this area may be a sign of local compression of the nerve, known as pronator syndrome ; however, more distal median nerve compression at the level of the carpal tunnel may also be associated with tenderness to palpation of the nerve near the elbow. Compression of the median nerve near the elbow seldom causes distinct sensory or motor deficits in the distal distribution of the nerve, but is usually associated with deep, aching discomfort in the proximal forearm that is aggravated by activity and relieved by rest. The brachial artery is found directly lateral to the nerve. With the elbow in extension, both of these structures, which lie on the surface of brachialis, are thrust anteriorly. The arterial pulse can then be easily palpated and the position of the nerve inferred ( Fig. 8-4 ).
The biceps tendon crosses the anterior elbow centrally and is readily palpated as elbow flexion is resisted (see Fig. 8-4 ). This is accomplished most easily by having the patient place his or her hand and wrist beneath the edge of the examining table and attempt to flex the elbow. As we begin to lose the feel of the tendon distally, it continues toward its insertion on the bicipital tuberosity of the radius, which is not directly palpable. A strong fascial continuation of the tendon, the bicipital aponeurosis, or lacertus fibrosus, continues medially to blend with the fascia overlying the flexor-pronator musculature.
Rupture of the biceps tendon usually occurs in young or middle-aged men who experience an unexpected extension force to the elbow. Acutely, these injuries result in significant pain, swelling, and ecchymosis in the cubital fossa. If the patient does not seek medical attention until after the acute symptoms subside, some anterior elbow discomfort is usually still accompanied by a feeling of weakness, particularly involving activities that require forceful supination of the forearm. In either circumstance, the palpable absence of the biceps tendon in the cubital fossa is diagnostic. If the bicipital aponeurosis remains intact, the anterior tendon defect and the obvious proximal retraction of the muscle belly of the biceps with attempts at active elbow flexion are not quite as obvious, but usually can be appreciated by comparison with the contralateral extremity. When the patient voices complaints of anterior elbow pain and weakness and the tendon is obviously palpable, consideration must be given to the possibility of partial tendon rupture. Other less commonly encountered diagnostic possibilities include cubital bursitis and bicipital tendonitis . It is generally not possible to distinguish these conditions by examination alone; imaging of the soft tissue is usually required.
The lateral antebrachial cutaneous nerve is the distal, purely sensory, continuation of the musculocutaneous nerve into the forearm. This nerve emerges from behind the lateral border of the biceps at the level of the interepicondylar line and becomes subcutaneous by piercing the deep fascia in this area, continuing distally into the anterolateral forearm. Irritation or entrapment of the nerve in this area is another, albeit uncommon, cause of anterior elbow pain and is usually accompanied by paresthesias radiating down the anterolateral forearm. Overzealous retraction of the nerve during anterior elbow surgery is the most common cause of these symptoms.
The brachialis muscle forms the floor of the cubital fossa and is intimately applied to the anterior capsule of the elbow. Snapping of a prominent medial tendinous portion of the brachialis muscle over the humeral trochlea has been reported as a cause of anterior elbow pain and swelling, also resulting in neuropathic symptoms in the distribution of the median nerve.
Medial
The medial epicondyle is the most obvious landmark on the medial side of the elbow. The flexor-pronator muscle group originates here and from the distal 2 to 3 cm of the medial supracondylar ridge of the humerus ( Fig. 8-5 ). Pain produced by palpation just distal to the tip of the medial epicondyle that is exacerbated by resisted wrist flexion is indicative of medial epicondylitis (golfer’s elbow) . In adolescence, pain to palpation directly over the tip of the epicondyle may represent apophysitis . The epitrochlear lymph node is located approximately 4 cm proximal to the medial epicondyle, usually just anterior to the supracondylar ridge and the medial intermuscular septum, which arises from it. Normally not palpable, this node may occasionally be enlarged in the presence of severe hand infection and is often markedly inflamed and tender in cases of cat-scratch disease ( Bartonella infection).
