CLINICAL EVALUATION OF THE ELBOW IN THROWERS

Transcription

1 CLINICAL EVALUATION OF THE ELBOW IN THROWERS JAMES R. ANDREWS, MD, JAMES A. WHITESIDE, MD, AND CRAIG M. BUETTNER, MD The elbow is a vital part of the complicated and intricate mechanism known as throwing. The athlete that participates in a throwing sport walks a fine line between success and injury. It is this line that the clinician must monitor. When an athlete admits that an injury has occurred, it is up to the physician to listen, observe, and examine the player in great detail. Injuries that involve the elbow are complex and difficult to evaluate; therefore, it is essential that a thorough, complete, and reproducible evaluation be performed every time. Not only is this important initially, but is invaluable when following up on the athlete over the course of the injury. The patient's history is the initial tool used to narrow the differential diagnoses. Questioning is concise, structured, and not leading. The result is a workable list of possible diagnosis that will aid the examiner when the physical examination is performed. The physical, like the history, is well outlined and defined. This methodology allows the clinician to be structured when evaluating the results. In the end, a complete history and physical examination may not be enough to draw a final conclusion to the etiology of the athlete's elbow injury. Ancillary studies should then be evaluated for their value and effectiveness in aiding the examiner to achieve a correct diagnosis. The purpose of this report is to provide the clinician a template that will give consistent results and aid in the diagnosis of elbow injuries. KEY WORDS: throwing, history and physical, injury, testing The examination of the elbow in throwers can be a complicated and difficult evaluation if not performed in a systematic manner every time. Care should be taken to rule out pathology other than that of the elbow, such as shoulder, spine, or wrist injuries that give rise to elbow pain. Once the focus of the examination is on the elbow, it is necessary not only to perform a careful and complete physical exam, but also first to focus on the patient's history before the injury, the situation surrounding the injury, the treatment once the injury occurred, and the effects of the injury on the thrower's effectiveness and mechanics. In the thrower, the elbow is a key component to the throwing motion and any injury to it requires prudent investigation to outline treatment and prognosis. HISTORY "If you will listen to your patients, they will tell you what is wrong with them" (author unknown). Taking a complete history of the patient is as important as completing a careful examination. It is through a complete history that the examiner can narrow down the etiology of the thrower's pain. Using a thorough, reproducible, and complete format when taking a patient's history will ensure that the examiner will not leave out any important details that will aid in diagnosis. Slocum's 1 original classification, which included medial tension, lateral compression, and extension injuries, has been modified in one form or fashion by many different authors. 2-5 Through this framework, a From the American Sports Medicine Institute, Birmingham, AL. Address reprint requests to James R. Andrews, MD, American Sports Medicine Institute th St S, Birmingham, AL Copyright 1996 by W.B. Saunders Company /96/ /0 regional approach has proven to be extremely effective for assessment of the throwing elbow. Where Does the Thrower Hurt? Pain can be difficult at times for the athlete to ~dentify and, as will be discussed later, can be a significant part of the patient's history. If the athlete identifies pain at the medial aspect of the elbow, then the examiner can focus on a differential that includes: ulnar collateral ligament (UCL) strains/disruptions, medial epicondyle avulsion fractures, medial epicondylitis, ulnar neuritis/subluxation, loose bodies, olecranon stress fractures, and valgus extension overload syndrome. Less common disorders such as fascial compression or pronator teres syndrome as described by Bennett 6 should be included in the differential for medial elbow pain. Pain located in the lateral aspect of the elbow of the thrower should alert the examiner to the possibility of radiocapitellar chondromalaeia, loose bodies, posterior interosseous nerve entrapment, radial head fractures, lateral epicondylitis (from a great deal of batting practice), or "tennis elbow,' '7 and in the skeletally immature, pain could be a sign of osteochondritis dissecans, s,9 Posterior pain should focus the examiner on valgus extension overload syndrome, pronator teres syndrome (which is entrapment of the median nerve at the level of the pronator teres), triceps tendonitis, or oleeranon avulsion. I When Did the Injury First Occur? The second part of this question is has the thrower repeated the same injury? In the throwel, it is vital to determine if the signs and symptoms are chronic or acute in nature. Chronic injuries include UCL strain or rupture, valgus extension overload, musculotendinous strains, and Operative Techniques in Sports Medicine, Vol 4, No 2 (April), 1996; pp

2 LATERAL: radiocapitell chondr osteochondj loose I radial head I lateral epico O.C.D. lesic Posterior int nerve ANTERIOF i anterior ca1, distal bice!: brachialis.~ distal bicel: coronoid o,' ERIOR: syndrome tendonitis tendon avulsion ~r teres ndrome 1on stress Fx hondral ~se bodies 1on bursitis,l: strains/tears epicondyle ulsion fracture eudtis ubluxation epicondylitis "~ondral )se bodies ton stress Fx syndrome )r teres yndrome helpful to know the time period involved with the thrower's pain. How Did the Injury Occur? In the thrower, did the injury occur with the throwing act? Did it occur from batting? Was it traumatic? How does the pain present? Is pain noted after throwing and improves by the next day? Does the pain occur during the throwing motion and after throwing for a certain period of time? Is the pain present even with activities of daily living? How does the elbow disorder effect the thrower's effectiveness? Does the thrower complain that there is a loss of velocity or decreased accuracy? Have his or her mechanics changed? Particularly in the training room setting, it is important to have the athletic trainer discuss the thrower's mechanics with the coach. Albright 11 has shown a threefold increase in elbow problems with a side arm delivery. The recognition that a curve ball is more detrimental than a fast ball to the thrower's elbow has not been substantiated. 12 What has been recognized clinically is that most acute injuries occur when the athlete is trying a little harder than usual, either as a result of the presence of scouts, a radar gun, or a rival team in a big game. The thrower is particularly susceptible once the arm is fatigued. What Does the Pain Feel Like? Fig 1. Anterior view of the elbow showing regional location of injury. osteochondral defects that progress to degenerative changes. The majority of complaints of pain in the throwing athlete are slow to progress and chronic in nature. Occasionally, the pain will be described as acute. Acute pain could result from acute UCL rupture (sometimes associated with a pop) or medial epicondyle avulsion, bicipital rupture, loose body formation, acute inflammatory reactions in the musculotendinous units about the elbow, or acute subluxation of the ulnar nerve. It can be achial ous Fig 2. Anterior and dorsal views showing the sensory innervation of the upper extremity. Acute, medial, sharp pain with an associated pop may result from a UCL rupture. Pain described as "lancinating" from the medial aspect of the elbow down the medial forearm with associated paresthesias of the fourth and fifth digits, sometimes described as a "clumsiness or heaviness," can occur with ulnar neuritis. When ulnar neuritis is present, up to 40% of the athletes will have UCL laxity. 13 Subluxation of the ulnar nerve is sometimes described as a snapping or popping sensation. If the thrower complains of posteromedial pain that occurs more with intense efforts than with mild to moderate throwing, it may be a sign of valgus extension overload (VEO). 10'14-16 Localized crepitus or popping also may be described with VEO. Pain located directly posterior at the insertion of the triceps is an indication of triceps tendinitis. Poorly localized, posterior, deep aching can be associated with an olecranon stress fracture that is an uncommon etiology for elbow pathology. 17,18 Pain may be associated with limited full extension as a result of olecranon hypertrophy, spurring, or loose body formation. Lateral elbow pain can be difficult to localize. Lateral elbow pathology in the radial-capitellar joint can develop loose bodies that produce true locking because the fragment is trapped between articular surfaces. These lesions include radial head fractures and osteochondritis dissecans lesions of the capitellum. Anterior elbow discomfort that can be well localized to the insertion of the distal biceps tendon or brachialis that is acute and sharp in nature could result from acute bicipital tendon rupture. Persistent aching as seen in acute inflammatory reactions can occur either in the anterior capsule or in the brachialis or distal biceps musculotendinous units. With flexion, anterior elbow pain can be an indication of the presence of a coronoid osteophyte. 78 ANDREWS ET AL

3 PHASE OF THROWING It is helpful to pinpoint the phase of the throwing motion that initiates the athlete's pain. It should also be pinpointed at what point during the motion the elbow pain is worse. 19 As mentioned in the previous line of questioning regarding pain in the thrower, it may be difficult for the athlete to accurately locate the area of pain. Likewise, it is often difficult for the athlete to pinpoint the most painful phase of throwing. Although difficult at times, questions by the examiner should not lead the player to his or her answers. During the early cocking phase, pain may develop from dynamic muscle tension in both the biceps and triceps and that lead to tendinitis. In late cocking, valgus stresses increase on the medial aspect of the elbow. If the UCL is incompetent, there will be increased tension on the ulnar nerve that produces symptoms of ulnar neuritis. Throughout the acceleration phase, the forces on the UCL continue to increase. In addition, there is progressive shearing impingement on the posteromedial olecranon and on the medial trochlea that results in VEO syndrome. 14,2-22 The throwing athlete may describe missing the target high and outside because of an early release or he or she may describe an inability to let the ball go. During late acceleration and follow-through, forceful wrist flexion and forearm pronation occur regardless of the type of pitch thrown. Anterior pain in the flexor-pronator musculotendinous unit may result from the forceful wrist flexion and forearm pronation. Signs and symptoms of the pronator teres syndrome occur during late acceleration and followthrough that results in a compression of the median nerve. Laterally, with late acceleration and follow-through, the radiocapitellar joint in the skeletally immature elbow undergoes considerable compression and shear. With deceleration, the elbow undergoes large eccentric loads that are generated primarily by the biceps and brachialis musculotendinous complexes. Deceleration is recognized as the most violent phase of the throwing motion. Because of these large loads, the biceps and brachialis can be injured. PHYSICAL EXAMINATION After the completion of a thorough patient history, the examiner should have a differential diagnosis in mind that will help to direct the focus of the physical examination. The physical exam, like the history, should be methodical and complete. A methodical approach allows the examiner to reproduce the examination on a consistent basis. It is important to note that even the best history of an elbow injury may not produce a clear-cut) differential diagnosis. Also, if the questions are too leading the history may be inaccurate. It is because of the difficulty in obtaining an adequate history from the patient that makes performing a complete physical examination every time so vitally important. In examining the throwing athlete, the examiner needs to approach the elbow like any other physical exam. First, the whole upper trunk should be exposed, including the uninvolved side. Throwers differ from the normal population. The uninvolved side always should be examined first. The examiner then has an idea of what is normal and that is very important when attempting to determine the pathology on the involved side. Inspection The throwing elbow has several abnormalities that, on inspection, can be obvious, but these abnormalities are not pathologic. The first abnormality is an increased carrying angle. The carrying angle is determined with the arm extended and the forearm fully supinated. The axis of the upper arm (humerus) and the forearm form the carrying angle. The normal carrying angle is approximately 11 in males and 13 in females. In the throwing athlete, particularly the older pitcher, a 10 to 15 increase in the athlete's dominant arm carrying angle may be evident. 15,18 These changes are secondary to adaptive remodeling that result from repetitive bony stress. An increase in the carrying angle is termed cubitus valgus. If cubitus varus is found, trauma and a supracondylar fracture should be suspected. Inspection of the forearm and measurement of the girth should be obtained. In the thrower there is usually an increase in muscular size in the dominant upper limb. Tone of specific musculature also should be inspected and observed for evidence of tendon avulsion or muscle atrophy. Other changes that lie within the skin are more pathologic and can be extremely helpful in elucidating the athlete's problem. The examiner should look for signs of ecchymosis, burns, and/or surgical scars. Redness may be a sign of cellulitis and blanching a sign of vascular insufficiency. Petechiae could result from a platelet deficiency. Swelling over the olecranon could result from inflammation of the olecranon bursa. Swelling in the area of the soft spot (formed by radial head, capitellum, and olecranon) can result from a joint effusion, synovial proliferation, or fluid accumulation. Thin, taut, adherent skin over the lateral epicondyle in an athlete with a history of lateral epicondylitis may indicate tissue damage from recurrent injections for this condition. Palpation When palpating the elbow, knowledge of the bony and soft tissue anatomy, as discussed in an earlier report in this issue, is vital. Knowledge of the anatomy allows the examiner to delineate specific injuries in a joint that can be difficult to examine. Specific structures must be palpated to locate a deformity or a painful area that may be present. Examination of the uninjured side for comparison is extremely helpful. The medial and lateral epicondyles, along with the olecranon tip, should be palpated and viewed posteriorly. At full extension, these landmarks should line up as a straight line. With 90 of flexion, they should form a equilateral triangle. Disruption of this triangle may indicate a fracture, a malunion, an unreduced dislocation or a growth disturbance of the distal humerus. 23 Palpation of the medial aspect of the elbow begins at the supracondylar ridge. The supracondylar ridge may give rise to osteophyte formation that is capable of median nerve impingement, and a congenital medial supracondylor process. A fibrous band from the congenital medial supracondylor process that arches to the medial epicondyle may compromise the brachial artery and the median nerve. The medial epicondyle itself should be palpated for tenderness and/or deformity. The medial epicondyle is the CLINICAL EVALUATION OF ELBOW IN THROWERS 79

4 origin of the common flexor-pronator group that includes the following: (1) the pronator teres, (2) the flexor carpi radialis, (3) the palmaris longus (4) the flexor carpi ulnaris, and (5) the flexor digitorum superficialis. The ulnar collateral ligament, specifically the anterior oblique portion, originates from the base of the medial epicondyle and inserts on the sublime tubercle on the medial aspect of the coronoid process of the ulna. Injuries in the area of the medial epicondyle may be difficult to differentiate from each other because of the proximity of the adjacent structures. Flexion of the elbow to 100 aids in uncovering the distal insertion of the anterior oblique portion of the UCL and facilitate evaluation. Tenderness at the origin of the flexor-pronator mass is an indication of golfer's elbow or medial epicondylitis. On the other hand, flexor-pronator muscle strains and rarely occurring complete tears of the muscle belly produce pain anterior and distal to the medial epicondyle. The ulnar nerve is easily palpable posteromedially within the ulnar groove. Normally, the ulnar nerve is sensitive to Tinel's testing. Characteristically, the inflamed ulnar nerve is extremely tender and sometimes doughy feeling. In about 15% of athletes, it may be possible to manually sublux the ulnar nerve from the cubital tunnel. The ability to sublux the ulnar nerve should be documented, especially in a thrower. Tinel's testing is perfoi~med above the cubital tunnel (zone 1), at the level of the cubital tunnel (zone 2), and distal to the cubital tunnel (zone 3). A positive test produces paresthesia in the 5th and ulnar-half of the 4th finger. Palpation of the posterior elbow structures begins with locating the olecranon. The olecranon is the most proximal portion of the ulna. In extension, the olecranon is captured by the olecranon fossa of the humerus. In flexion, the olecranon is readily palpable. Initially, the overlying olecranon bursa is palpated and then the bony structure of the olecranon examined. In VEO syndrome, there is osteophyte formation and/or inflammation in the area of the posteromedial olecranon. In the thrower, tenderness along the proximal one-third of the medial border of the olecranon, with or without a palpable bony prominence, may indicate a stress fracture. The proximal portion of the olecranon fossa is palpable in the partially flexed elbow with the triceps relaxed. The three heads of the triceps converge to form a aponeurosis that attaches to the tip of the olecranon. The long head lies posteromedial to the elbow, the medial head runs deep to the long head and is palpable over the medial aspect of the distal humerus, and the lateral head of the triceps courses posterolateral to the elbow. The triceps should be examined in both a relaxed and active state. The lateral region of the elbow gives rise to several possible reasons for lateral elbow pain. Abnormal bony architecture may be the etiology of a thrower's lateral elbow pain. When a valgus stress is applied to the thrower's elbow, particularly when repeated, the radiocapitellar joint undergoes compression. In the young athlete, the result may be osteochondrosis or Panner's disease. In the mature athlete, valgus stress produces articular fragmentation and bony overgrowth in the capitellum and the radial head with the possible progression to loose body formation. The lateral epicondyle is readily palpable by tracing the lateral supracondylar ridge distally. The radial head is palpable distal to the lateral epicondyle. Evaluation of the radial head is further enhanced by supination and pronation of the forearm. The "soft spot," as described before, lies beneath the anconeus. If pain is evoked with palpation of the radial head as the forearm moves through varying degrees of flexion with pronation and supination, a radial head fracture is suspected, even if the radiographs are unremarkable. Damage to the articular surface of the radiocapitellar joint is further delineated by axial loading of the joint while supinating and pronating the forearm repeatedly with the elbow extended. A positive radiocapitellar compression test elicits pain. The lateral elbow gives rise to the wrist extensor group or the "wad of Henry." This group includes the brachioradialis, the extensor carpi radialis longus, and the extensor carpi radialis brevis. The brachioradialis originates from the lateral supracondylar ridge and the extensor carpi radialis longus and brevis originate from the lateral epicondyle. The brachioradialis is examined for strength and size by placing the forearm in a neutral position, clenching the fist, and then estimating the amount of resisted elbow flexion. Active wrist extension increases the tone in the extensor carpi radialis longus and brevis. Direct palpation and pain with activity at the origin of the "wad of Henry" alerts the examiner to think of lateral epicondylitis. Lateral epicondylitis is usually associated with batting, not throwing. Lateral ligamentous damage is rare in the thrower. Neurologic injuries can occur at the level of the supinator and pain in this area of the elbow may indicate compression entrapment of the posterior interosseous branch of the radial nerve. More proximally, increased tenderness indicates radial tunnel syndrome or injury to the radial nerve. Pain in the anterior aspect of the elbow may result from pathology located exclusively in anterior structures as well as medial and lateral structures that course anteriorly. The flexor-pronator mass and the brachioradialis can undergo muscle hypertrophy from repetitive use and produce exercised-induced edema and increased fascial pressure that results in anterior elbow pain. The distal biceps tendon inserts anteromedially in the antecubital fossa and is readily palpable with the forearm supinated and the elbow actively flexed. Poorly localized anterior pain at times results from anterior capsulitis. Anterior capsulitis, biceps and brachialis tendinitis, and possibly coronoid hypertrophy are usually associated with hyperextension injuries. It is postulated that a "checkrein phenomenon" of extensor overload may contribute to the development of these anterior findings. 4 Biceps and brachialis tendinitis is further delineated when increased pain is produced from resisted forearm supination and active elbow flexion. Neurologic injuries that are reflected in the anterior aspect of the elbow may cause significant pain. The median nerve, when compressed at the level of the laceratus fibrosis (which is the medial termination of the bicipital tendon) or when involved in the pronator teres syndrome as a result of repetitive athletic pronation, forced gripping, or direct trauma, produces anterior forearm discomfort. Characteristically, the compression symptoms can vary from vague postexertional pains in the proximal volar aspect of the forearm to paresthesia of the thumb, index 80 ANDREWS ET AL

5 and long fingers. The Phalen test and Tinels at the carpal tunnel are negative. Late occurring signs from the pronator teres syndrome include weakness and parethesias of the median nerve and innervated intrinsic muscles. Extrinsic muscles innervated by the anterior interosseous nerve function normally. There is an anterior interosseous nerve syndrome that is associated with athletic overuse situations. In the anterior interosseous nerve syndrome, the throwing athlete often complains of poor mechanical function of the thumb, index, and long fingers. A test for a positive anterior interosseous nerve syndrome, the pinch maneuver, shows the distal phalanx of the index finger to be hyperextended when the proximal interphalangeal joint is hyperflexed. The athlete then is unable to make the typical OK sign, because pulp contact between the thumb and index finger is more proximal. The anterior interosseous nerve has no cutaneous sensory fibers to evaluate. The pronator teres syndrome can be differentiated from the anterior interosseous nerve syndrome by testing resisted pronation of the forearm through a range of motion from 90 of flexion to full extension. This maneuver results in a compression of the median nerve at the level of the pronator teres that intensifies proximal anterior forearm pain. Compression-induced pain at the lacertus fibrosis can be magnified by resisted supination with the elbow flexed. In the thrower, pronator teres and anterior interosseous nerve syndromes occur primarily because of muscle hypertrophy or secondarily from exercise-induced edema. Range of Motion The essential motions of the elbow are flexion, extension, pronation, and supination. When examining an individual's range of motion, always compare the degrees of motion with the unaffected side. In the thrower, it is not uncommon for the athlete to have a flexion contracture if he or she has pitched a large number of innings. The amount of the flexion contracture is noted to increase as the season progresses and may decrease in the offseason. A younger, less experienced pitcher may exhibit hyperlaxity that includes hyperextension of the elbow. The normal range of motion of the elbow is from 0 of extension to approximately 150 of flexion. 17,18,23 Flexion may be decreased and yet be normal when there is hypertrophy of the biceps, brachialis, and wrist flexors. Pathologic reasons for a lack of extension include capsular sprain, flexor muscle strain (as previously discussed), and intra-articular loose bodies. Abnormal lack of full flexion may arise from loose bodies, capsular tightness, triceps strain, anterior osteophytes, or coronoid hypertrophy. The range of pronalion and supination motion should be evaluated bilaterally. The normal arc for pronation is about 0 to 85 and supination is approximately 0 to ,18,23 A change in the normal arc of the forearm should alert the examiner to possible loose bodies, radiocapitellar osteochondritis, radial head subluxation, or motor nerve entrapment manifesting as paresis of either the biceps, pronator teres, pronator quadratus, or supinator musculature. Increased forearm fascial compartment pressure from overuse also may cause a decrease in range of motion and must be considered in the differential diagnosis. Evaluation of the athlete's elbow for the presence of Muscle TABLE 1. Motor Testing of the Muscles of the Elbow Brachialis Biceps brachii Brachioradialis Triceps brachii Anconeus Flexor-pronator mass Extensor carpi radialis Iongus dorsum 2nd metacarpal Extensor carpi radialis brevis dorsum 3rd metacarpal Extensor carpi ulnaris Test Elbow flexed, forearm pronated Forearm supinated, shoulder flexed 45 to 50 degrees Elbow flexed, forearm neutral Shoulder flexed 90, elbow flexed 45 to 90 Shoulder flexed 90, elbow flexed 45 to 90 Arm at side, elbow flexed 90, alternating pronation supinator and supination Elbow flexed 30, resistance Elbow fully flexed, resistance Resisting ulnar deviation crepitation is performed while examining both active and passive range of motion. Crepitus that initially is not found through passive motion may be unveiled through the active range of motion. Limitation of motion is further delineated in the same manner. If the motion is full on passive testing but limited on active motion, then it is safe to assume that pain is the limiting factor and not a mechanical block. Strength Evaluation Certain musculature about the elbow and methods of testing strength have been discussed previously. When possible, it is important to delineate the involved, injured muscle to better tailor the athlete's therapy. Table i lists the muscles about the elbow and functional tests. 24 Table 2 denotes the sources of pain involved in each phase of throwing. 14 Reflexes The reflexes in the upper extremity are important and must be evaluated. The biceps reflex is elicited to evaluate the C5 nerve root. The C6 nerve root is tested by performing the TABLE 2. Defining the Phase of the Throwing Motion in Which the Pain Occurs Can Aid in the Diagnosis Phase of Throwing Early cocking Late cocking Acceleration Follow-through Deceleration Source of Pain Demonstration Distal biceps tendonitis Distal triceps tendonitis UCL strain UCL rupture Ulnar neuritis UCL strain UCL rupture Ulnar neuritis VEO syndrome Flexor-pronator mass strain Pronator teres syndrome Panner's disease OCD lesion of the capitellum Flexor-pronator mass strain Pronator teres syndrome VEO syndrome Panner's disease OCD lesion of the capiteilum VEO syndrome Distal biceps tendon avulsion Distal biceps tendon strain Brachialis strain CLINICAL EVALUATION OF ELBOW IN THROWERS 81

6 TABLE 3. Summary of the Components of an Elbow Exam HISTORY Where is the pain? When did the pain begin? How did the pain start? What does the pain feel like? What phase of throwing does the pain occur? PHYSICAL Inspection Palpation Range of motion Motor strength Reflexes Sensory Stability Valgus extension snap brachioradialis reflex. Finally, C7 root integrity is noted by observing the triceps reflex. Increased response could signify an upper motor neuron lesion, whereas a decreased response could result from a lower motor neuron lesion. Sensory The sensory exam is dependent on the patient's subjective response to light touch and/or pinprick. The lateral arm is innervated by branches of the axillary nerve (C5, C6 root), and the lateral forearm is innervated by branches of the lateral antebrachial cutaneous nerve (C5, C6, C7 root). The medial forearm is supplied by the medial antebrachial cutaneous nerve (C8, T1 root), and the medial arm is innervated by the medial brachial cutaneous nerve (C8, T1 root). Stability Testing When evaluating stability of the elbow in the throwing athlete, all eyes focus primarily on the anterior oblique bundle of the UCL. The UCL in the thrower is considered the anterior cruciate ligament of the elbow. The competency of the UCL must be carefully evaluated in a thrower with medial elbow pain. Without medial stability, the athlete is unable to participate competitively. If palpation produces pain in the area of the UCL, then medial stability testing is needed to further evaluate the UCUs competency. Medial elbow stability is determined with the athlete sitting, the elbow flexed to 20 to 30 to unlock the olecranon from its fossa, and the player's hand is trapped between the examiner's opposite upper arm and trunk. In this manner, both hands are free to apply a valgus stress and to palpate the medial aspect of the elbow. The examiner seeks to show crepitation on the lateral side, pain medially, and an increased opening of the medial compartment when compared with the uninjured side. When assessing the degree of opening, the examiner, just like in anterior cruciate ligament testing, should note the endpoint. The second method to evaluate the UCL is performed with the player supine, the arm abducted to 90, and the elbow flexed to 20 to 30 to unlock the olecranon and a valgus force is directed posteriorly against a supinated forearm while palpating the medial compartment with the opposite thumb. An increased opening, in comparison with the uninjured side, is clinically important. Lateral elbow stability can be evaluated by reversing the valgus stress to a varus force with the athlete seated. Lateral instability is a rare problem in the thrower. Valgus Extension Overload Test As previously discussed, the throwing athlete subjects the elbow, and specifically the olecranon, to an abnormally high amount of valgus stress and extension. Therefore, by design, the olecranon develops posteromedial impingement and shear on the olecranon and its fossa. As a result, degenerative changes occur that result in articular cartilage damage and osteophyte formation. VEO can eventually limit the thrower's effectiveness because of the ensuing pain. The VEO test or valgus extension snap maneuver, which more aptly describes the maneuver, consistently produces discomfort when impingement and articular damage of the VEO syndrome are present. To perform the examination, place the player in a seated position, apply a moderate amount of valgus stress to the elbow, and then forcefully move the elbow from about 30 of flexion to full extension. This VEO testing maneuver simulates the posteromedial olecranon 'impingement and pain that occur in the late acceleration phase of pitching and corresponds closely to the thrower's complaints. 14,16,23 CONCLUSION The elbow is a complex and difficult joint to examine. Even with the most thorough evaluation, the etiology of the thrower's pain is still often confusing (Table 3). To minimize the confusion, it is important to begin the evaluation with a complete, thorough, and nonleading history from the patient. After obtaining the history, the examiner should have an idea of the area that is injured, when it occurred, and the mechanism of the injury. In addition, it is important to evaluate the phase of throwing effected and the mechanics of each individual thrower. Likewise, the physical exam should be thorough, methodical, reproducible, and complete. The combination of the patient's history and the physical examination should then yield a precise differential diagnosis. Further diagnostic studies (ie, stress films or saline enhanced magnetic resonance imaging), if necessary, are then considered to aid the examiner in a final determination of the etiology of the thrower's elbow pain. The last area that is taken into consideration is the time of the year and its relationship to the player's season. Once the diagnosis is established, the examiner should outline the prognosis and the treatment plan in relationship to the immediate season and, more importantly, to the athlete's long-term goals. Athletes tend to be short-term minded; therefore, it is up to the physician, along with the trainer and the coach, to outline the future treatment plan and expected outcome as clearly and concisely as possible. Often, these decisions are difficult and painful. The physician must use every tool available, including the patient's history and physical examination, appropriate testing, roentgenological studies, and blood work, to arrive at and implement a correct diagnosis. REFERENCES 1. Slocum DB: Classification of elbow injuries from baseball pitching. Tex Med 64:48-53, Jobe FW, Nuber GN: Throwing injuries of the elbow. Clin Sports Med 5: , ANDREWS ET AL

7 3. Dehaven KE, Evarts CM: Throwing injuries of the elbow in athletes. Orthop Clin North Am 4: , Barnes DA, Tullos HS: An analysis of 100 symptomatic baseball players. Am J Sports Med 6:62-67, Woods GW, Tullos HS, King JW: The throwing arm: Elbow joint injuries. Am J Sports Med 1:43-47, Bennett GE: Elbow and shoulder lesions of baseball players. Am J Surg 98: , Nirschl, RP: The epilogy and treatment of tennis elbow. J Sports Med 2: , Pappas AM: Elbow problems associated with baseball during childhood and adolescence. Clin Orthop 164:30-41, Hunter SC: Little leager's elbow, in Zarins B, Andrews JR, Carson WG Jr (eds): Injuries in the Throwing Arm. Philadelphia, PA, Saunders, 1985, pp Tullos HS, Bryan WJ: Examination of the throwing elbow, in Zarins B, Andrews JR, Carson WG (eds): Injuries to the Throwing Arm. Philadelphia, PA, Saunders, 1985, pp Albright JA, Jokl P, Shaw R, et al: Clinical study of baseball pitchers: Correlation of injury to throwing arm with method of delivery. Am J Sports Med 6:15, Sistro DJ, Jobe FW, Moyness DR, Antonelli DJ: An Electromyographic analysis of the elbow in pitching. Am J Sports Med 15: , Conway JE, Jobe FW, Glousman RW, Pink M: Medical instability of the elbow in throwing athletes: Surgical treatment by ulnar collateral ligament repair or reconstruction. J Bone Joint Surg Am 74A: , Wilson FD, Andrews JR, Blackburn TA, McCluskey G: Valgus extension overload in the pitching elbow. Am J Sports Med 11:83-87, King J, Brelsford HJ, Tullos HS: Analysis of the pitching arm of the professional baseball pitcher. Clin Orthop 67: , Miller CD, Sanote FH: Valgus extension injuries of the elbow in the throwing athlete. J Am Acad Orthop Surg 2: , Nicholas JA, Hershman EB: The Upper Extremity. Sports Medicine, St Louis, MO, Mosby, 1990, pp Andrews JR, Wilk KE, Satterwhite YE, Tedder JL: Physical Examination of the throwers elbow. J Orthop Sports Phys Ther 17: , Andrews JR, McCluskey GM, McLeod WD: Musculo-tendinous injuries of the shoulder and elbow in athletes. Athletic Training. 11:2, Tultos HS, King JW: Throwing mechanism in sports. Orthop Clin North Am 4: , Andrews, JR: Bony injuries about the elbow in the throwing athlete. Instructional Course Lectures; Injuries of the Upper Extremity in the Competitive Athlete. American Academy of Orthopaedic Surgeons, St Louis, MO, Mosby, 1985, pp Indelicato PA, Jobe FW, Kerlan RK, Carter VS, Shields CL, Lombardo SJ: Correctable elbow lesions in professional baseball players: A review of 25 cases. Am J Sports Med. 7:72-75, Volz RG, Morrey BF: The Elbow and its Disorders. Philadelphia, PA, Saunders, 1985, pp Kendall FP, McCreary EK: Muscles, Testing and Function (ed 3). Baltimore, MD, Williams & Wilkins, 1983, pp CLINICAL EVALUATION OF ELBOW IN THROWERS 83