Jeffrey R Dugas and Amy Bullens Borrow

In This Chapter

Acute dislocation

Ulnar collateral ligament (UCL) injury Nonoperative management Surgery—UCL reconstruction Posterolateral rotatory instability Elbow arthroscopy

ELBOW INSTABILITY

Relevant Anatomy

The elbow articulation allows two major motions: flexion-extension through the ulnohumeral and radiocapitellar joints and pronation-supination through the proximal radioulnar joint. The osseous configuration confers up to 50% of the stability of the joint when in full extension, but stability is increasingly reliant on soft tissues with increasing flexion. Disruption of the bony architecture as a result of fractures or dysplasias can affect the stability of the elbow and subsequently alter the motion and stresses placed on the soft-tissue supports. As an example, some fractures of the coronoid process can lead to significant elbow instability and increased stress on the radial head. The radial head is an important secondary restraint to valgus load that becomes the primary restraint with injury to the UCL. Thus, if the radial head is fractured, it is important to check the UCL for injury.

The soft-tissue stabilizers are the joint capsule, ligaments, and musculotendinous units.1 The major ligaments of the elbow are the UCL (ulnar collateral ligament) and the lateral collateral ligament (LCL) complex (Fig. 34-1). The UCL has two clinically important bundles: the anterior bundle and the posterior bundle. The LCL complex is the primary restraint to varus and posterolateral rotatory stress. The lateral UCL, connecting the lateral epicondyle of the humerus to the supinator crest of the lateral side of the ulna, is the most important stabilizer for pos-terolateral rotatory instability. The annular ligament stabilizes the proximal radioulnar joint1 and functions as a secondary restraint to posterolateral rotatory stress along with the common extensor origin, anterior and posterior capsules, and the radial collateral ligament, which is the portion of the LCL between the lateral epicondyle and the annular ligament.2

Epidemiology

The elbow is the second most common joint that is dislocated in adults, with most dislocations occurring in the posterolateral direction.3 The annual incidence is 6 to 8 dislocations per 100,000 people. Elbow dislocations account for 11% to 28% of elbow injuries.1 Although simple elbow dislocations are typically managed with closed reduction and early range of motion, a small percentage of patients continue to have instability symptoms, many of these due to posterolateral rotatory instability. The exact percentage is not known.

Medial instability can occur secondary to an elbow dislocation that was traumatic or can be secondary to chronic overuse. Although medial instability is rarely symptomatic in the non-overhead athlete, it can be problematic in activities of daily living or recreation and warrants investigation in such individuals. In the overhead athletic population, UCL injury is rarely the result of a frank dislocation but rather due to chronic overuse. Acute medial elbow instability can occur in overhead athletes but occurs more commonly in contact or tumbling sports. In football, UCL injuries can be an acute injury, but, as documented in a report by Kenter et al,4 even in the National Football League, UCL injuries that are acute rarely require operative intervention even in overhead athletes (e.g., the quarterback). It is similarly believed that an acute UCL injury to a baseball thrower also can be treated nonoperatively if it is secondary to trauma and the player has not previously had medial-side elbow pain. Chronic injuries are becoming an increasingly concerning problem, even in the high school baseball athlete, as we have seen a significant increase in the number of high school athletes seeking medical attention for medial-side elbow pain, secondary to UCL tears.

Acute Dislocation

Elbow dislocation usually occurs from a fall on an outstretched hand. It is theorized that valgus and axial load occur while the forearm is in supination (Hildebrand) and the elbow may be

INTRODUCTION

• The incidence of overuse elbow injuries is increasing at an alarming rate, particularly in the young overhead athlete population.

• With increasing frequency, injuries that were once limited to the elite professional are now being treated in the young adolescent. Awareness of these trends on the part of the treating physicians, trainers, therapists, and parents is crucial to injury prevention.

• This chapter is designed to review the injuries that occur to the elbow that cause instability, along with the evaluation and treatment of these injuries. As a related topic, elbow arthroscopy techniques and indications are reviewed.

Figure 34-1 A, The medial ligamentous structures of the elbow. Note the anterior band of the ulnar collateral ligament, which is the main stabilizer to a valgus stress. B, The lateral collateral ligament complex. (From Agur AMR, Lee MJ: Grant's Atlas of Anatomy, 10th ed. Philadelphia, Lippincott, Williams & Wilkins, 1999.)

Figure 34-1 A, The medial ligamentous structures of the elbow. Note the anterior band of the ulnar collateral ligament, which is the main stabilizer to a valgus stress. B, The lateral collateral ligament complex. (From Agur AMR, Lee MJ: Grant's Atlas of Anatomy, 10th ed. Philadelphia, Lippincott, Williams & Wilkins, 1999.)

slightly flexed or hyperextended. Elbow dislocations are classified by direction of dislocation as posterior, lateral, anterior, or divergent and also as simple or complex, depending on whether fractures are also present. Posterior or posterolateral dislocations are most common.

Elbow dislocations occur during a variety of sporting activities, both contact and noncontact. The effect of the injury on the athlete's return to play depends on the sport and position as well as associated injuries. Some sports are more commonly associated with elbow dislocations. A recent study highlighted the increase in elbow dislocations associated with winter sporting activities since snowboarding has become more popular. Snowboarders had 17 elbow dislocations (simple or complex) of 64 elbow injuries compared to 8 elbow dislocations of 152 elbow injuries in skiers.5

Treatment of acute simple elbow dislocations begins with a good history and examination of the affected extremity. While obtaining the history, the mechanism of injury, previous injury to the affected extremity, symptoms of numbness, paresthesias, weakness, and excessive pain should be sought. Physical examination should involve inspection, palpation (elbow, forearm, shoulder, wrist, and hand) as well as a thorough neurologic and vascular examination of the affected extremity and comparison to the unaffected extremity before reduction. Reduction should be performed with adequate sedation and should be followed by a postreduction radiograph showing concentric reduction. There are many techniques to reduce posterior elbow dislocations, but the most common method is by longitudinal traction of the forearm with the elbow held in about 30 degrees of flexion while an assistant is holding countertraction on the upper arm. If any medial or lateral translation is present, it is corrected first, then the olecranon is pushed distally with the thumb of the person performing the reduction. Once the elbow is reduced, it is fully flexed. Prior to splinting, the elbow should be taken through a range of motion to determine the stable arc of motion. Checking for instability of the UCL should be performed and the forearm should be pronated and supinated while the elbow is flexed and extended. If there is isolated damage to the UCL, then the elbow will be more stable with the forearm in supination. If the LCL complex is damaged without damage to the UCL being present, then the elbow will be more stable with the forearm in pronation. If both ligaments are damaged, then the elbow is best splinted with the forearm in neutral.1 The elbow should be splinted, and then an early range-of-motion program begun as early as 3 days postreduction. In some cases, a hinged brace can be employed with increasing degrees of extension allowed as the healing process progresses.1 It is rare for a simple elbow dislocation to be irreducible by closed means or for immediate surgical repair or reconstruction of the ligaments to be required.

There has been a recent trend to shortening the immobilization period even further. In a study performed at the Naval Academy, 20 posterior elbow dislocations were treated on postreduction day 1 with an active range-of-motion protocol. They were seen on nearly a daily basis for a supervised range-of-motion program and supplemental modalities such as cryo-therapy, electrical stimulation, and compression bandages to reduce swelling for 2 weeks. These patients achieved their final range of motion in 19 days. All patients achieved range of motion within 5 degrees of the unaffected elbow. Only 15% had heterotopic ossification on follow-up radiographs, none of which were clinically significant. No early redislocations occurred. One patient had a redislocation 15 months later in a contact injury and was treated with the same protocol without further incident. No other cases of instability occurred.6

Common sequelae of acute simple elbow dislocations include loss of motion of the affected elbow, heterotopic ossification, and recurrent instability. Loss of motion is the most frequent complaint, with loss of 10 to 20 degrees of extension not uncommon.3 Heterotopic ossification can occur in as many as 55% of patients.1 Degenerative changes were also found after dislocation in some patients.3 Neurovascular injuries can occur in simple dislocations and must be identified in the initial assess ment in order to avoid potentially disastrous complications. The brachial artery can become entrapped as can the median or ulnar nerves. Treatment is exploration of the affected structures immediately upon discovery of the problem.

Return to play is based on sport-specific and position-specific requirements. In the early postdislocation period, a noncontact athlete may be able to perform at competition level with a hinged brace for protection. In contact sports, even a hinged brace may not be enough protection. Certain minimal goals should be achieved before return to play in any sport. These include return of range of motion, normal neurovascular examination, and relative stability through the functional range of motion for the sport. Soft-tissue healing is generally adequate to begin ligament-stressing exercise by 6 weeks after the injury. Return to contact sports with a brace can be considered after stability is restored but should be individually based. As a general rule, we do not like to remove a protective brace from an athlete during a competition season. If an athlete suffers an elbow dislocation and we begin bracing for sport activity, we continue the brace until the end of the season. If the elbow is stable after the season is over, bracing is not required for further participation in subsequent seasons.

MEDIAL INSTABILITY

Medial elbow pain in the overhead athlete should be taken seriously by both the player and health care team. Medial instability secondary to UCL injury should be suspected and ruled out. Chronic medial instability can be caused by chronic overuse due to repetitive intrinsic stress such as muscular contraction or extrinsic stress due to tensile overload.7 This can lead to microtears in the UCL that, if not given appropriate time to heal, can lead to attenuation and medial instability.

Relevant Anatomy

The UCL is the primary restraint to valgus stress, with the radial head being a secondary restraint. The UCL has two components: the anterior bundle and the posterior bundle. The anterior bundle is the primary restraint to valgus stress to the elbow when it is at 30, 60, or 90 degrees of flexion.8 Its origin is the anteroinferior aspect of the medial epicondyle of the humerus and its insertion is the medial portion of the coronoid process, an area called the sublime tubercle.9 Its mean length is 27.1 ± 4.3mm and mean width, in one study, is 4.7 ± 1.2mm.8 An unpublished study done at our institution, regarding the anterior bundle of the UCL, showed that the mean proximal width of the ligament is 6.8 ± 1.4 mm and mean distal width is 9.2 ± 1.6 mm. Also noted in this cadaveric study was a mean distance of 2.8 mm from the proximal edge of insertion of the ligament into the ulna to the ulnar articular cartilage edge.10

Biomechanics of the Ulnar Collateral Ligament and Pitching

The majority of stress present in the UCL occurs during the late cocking and early acceleration phases of throwing.11-13 The baseball pitch occurs with the elbow flexed from 90 to 120 degrees during the acceleration phase of throwing, after which the elbow rapidly extends.14 The elbow is then subjected to distraction stress during extension in the release phase. The UCL accounts for 54% of the valgus stability during elbow flexion of 90 degrees and resists 78% of distraction during the release phase.15 The static torque experienced by the UCL in the course of overhead throwing is nearly the same as the ultimate strength of the lig ament itself.12 Tensile stress occurs in the medial compartment subjecting the UCL, flexor-pronator mass, ulnar nerve, and medial epicondyle apophysis in the skeletally immature athlete to tremendous stress. Shear stress occurs in the posterior compartment subjecting the olecranon and olecranon fossa/trochlea to injury. Compression laterally occurs during throwing, which subjects the radiocapitellar joint to injury. Thus, if the medial elbow is chronically unstable, other areas of the elbow can have clinical findings as well, such as chondromalacia and osteophyte formation as a result of microinstability. Subtle laxity may present with symptoms of ulnar neuritis or flexor-pronator ten-donitis. All cases of elbow pain in the throwing athlete should be checked for UCL laxity as an underlying cause.13

History

Overhead athletes presenting with medial elbow pain need a very detailed history taken for diagnostic as well as educational purposes. Information on onset of symptoms, the phase of throwing in which the symptoms occur, training changes, previous injuries to the elbow or shoulder, changes in velocity and accuracy, which types of pitches are painful, the number of innings pitched in recent seasons, and associated symptoms such as nerve and vascular symptoms should all be collected.7,13,16 Eighty-five percent of patients have pain in the acceleration phase and less than 25% have any pain in the deceleration phase.13,17 In some patients, the offending pitch can be identified as causing an acute rupture of the UCL, but more often the pain comes on gradually and becomes more persistent and painful over time. Ulnar nerve symptoms such as paresthesias in the fourth and fifth digits are present in nearly one fourth of patients; some authors have found ulnar neuritis in as many as 40%.7,11 Nineteen percent have accompanying posterior elbow pain as noted in one study.11 Any history of previous treatment such as therapy, injections, and surgery is essential to interpreting current signs and symptoms as well as radiographic studies.

Physical Examination

Physical examination should begin with an inspection of the elbow for any deformity, limitation of motion, swelling, or bruising. Carrying angle averages 11 degrees in men and 13 degrees in women. Some asymptomatic professional throwers can have carrying angles exceeding 15 degrees. Elbow flexion contractures are seen in 50% of professional throwers as well. Neither finding is necessarily indicative of an injury but is important to note nonetheless.13,18

Palpation of the elbow should include all bony prominences as well as the UCL, flexor-pronator origin, ulnar nerve, and other soft-tissue structures. The UCL is best palpated with the elbow in 50 to 70 degrees of flexion.13 Point tenderness is most common 1 to 2 cm distal to the medial epicondyle.7 Palpation of the ulnar nerve for tenderness, subluxation, and Tinel's sign as well as distal motor and sensory examination should be performed to evaluate for ulnar neuritis or neuropathy.13 Palpation of pulses should also be performed.

Testing the elbow for medial laxity is best performed with the elbow flexed at 30 degrees, forearm pronated, and the wrist passively flexed (Fig. 34-2). The patient can also be placed supine with the arm abducted and the shoulder maximally external rotated. This position provides the examiner with the easiest position to hold the patient's arm and prevents shoulder rotation from clouding the examination. The pronation and wrist flexion, when done passively, relax the flexor-pronator mass and make the medial aspect of the elbow easier to palpate for joint

Figure 34-2 Clinical evaluation of the ulnar collateral ligament. The elbow is placed in 30 degrees of flexion and full pronation with the wrist passively flexed. The examiner places a valgus stress and assesses the end feel, the amount of valgus opening, and any pain elicited.

opening. This also decreases any potential dynamic stabilization that occurs.13 Andrews tests the laxity in the position described with the patient seated, then tests the stability also with the patient supine, the forearm supinated, and elbow flexed at 30 degrees. The test is then repeated with the patient prone with the elbow flexed 30 degrees and the forearm pronated. The Milking maneuver is also performed by grasping the patient's thumb and flexing the elbow to 90 degrees using the thumb to provide valgus stress. This was originally described with the patient grasping his or her own thumb with the opposite hand, but not all patients can perform this maneuver and the examiner needs to be able to simulate it in those patients who cannot. Valgus extension overload can be tested by repeatedly forcefully extending the elbow while placing a valgus stress on it. A positive test occurs when the patient has pain at the posteromedial olecranon tip as the elbow reaches full extension.7,13,19

Radiographic Studies

Radiographic studies are necessary in the evaluation of a throwing athlete with medial elbow pain. Anteroposterior, lateral, two oblique, an oblique axial with the elbow in 110 degrees of flexion, and stress views of both the affected and the unaffected extremity comprise a thorough radiographic examination.13 The oblique axial view is helpful for visualizing posteromedial osteo-phytes. The standard anteroposterior, lateral and two oblique views may appear normal or may show signs of chronic injury to the medial elbow such as medial osteophytes or calcifications within the ligament.8 Stress radiographs should be obtained bilaterally to compare the patient's overall ligamentous laxity. A difference of 2 mm is considered diagnostic of medial elbow instability.8

In the past, computed tomography arthrography was used frequently to check for UCL tears. Its sensitivity is 86% and specificity is 91%. Saline-enhanced magnetic resonance imaging is now the gold standard, with sensitivity of 92% and specificity of 100% (Fig. 34-3).20 Magnetic resonance imaging also has the added benefit of diagnosing other potential injuries such as injuries to the flexor-pronator origin. It was previously believed that the T sign of dye on a contrast study was diagnostic of UCL injury. Recent data suggest that the proximal fibers of the UCL insertion onto the sublime tubercle and the capsular fibers may

Figure 34-3 Contrast-enhanced magnetic resonance imaging of the elbow. Note the contrast extravasated distal to the elbow joint on the medial side. The ulnar collateral ligament is noted to have a tear in its midsubstance.

insert up to 3 mm distal to the articular surface, making the T sign a less-than-perfect diagnostic finding.10

Treatment Options

Once the diagnosis of UCL injury is made, the decision regarding treatment is made with careful consideration of the athlete's demands on the injured area (sport and position played), previous treatment of the injury (rest and rehabilitation done appropriately), and the degree of ligament injury. The vast majority of partial ligament injuries should be treated initially with conservative treatment. Complete injuries in nonthrowing athletes or low-demand throwing athletes may also be treated with a trial of conservative care. Nonoperative treatment consists of a period of rest, anti-inflammatory medi-cation, and therapy modalities such as cryotherapy to decrease pain. Range-of-motion exercises of the elbow and strengthening exercises of the flexor-pronator muscles should be performed during the rest period. Bracing may be used if necessary. In throwing athletes, shoulder strengthening should also be performed to prevent any shoulder injury from occurring when returning to throwing. After a period of "active rest," a throwing program should be instituted. Generally, the program takes about 3 months to complete if done properly.13,14 Some authors recommend a brace be worn at night in the "active rest" period and a hyperextension brace be worn in the throwing program. With this protocol, one study shows that 42% of players will return to play at the same level in 24 to 25 weeks. In the patients with an acute injury, 44% returned without the need for surgical treatment.14 It is very important to note that nonoperative treatment does not include any injections into the ligament or elsewhere in the elbow.13

Operative treatment is reserved for the overhead athlete with a complete tear or a partial tear that has failed nonoperative treatment. Select other athletes (e.g., gymnasts, wrestlers) may also be unable to return to their sports of choice and may also be considered for reconstruction. There are several different methods of reconstructing the UCL. These include the docking technique, the muscle-splitting approach using bone tunnels, and a suture anchor technique. Although UCL repair has not met with favorable results in overhead athletes, all the currently employed reconstruction techniques have enjoyed significant clinical success with high rate of return in elite athletes. Our preference is to use a modification of Jobe's original technique, including ulnar nerve transposition to a subcutaneous location beneath a leash of flexor-pronator fascia. This preference is born out of nearly 2 decades of experience at our institution with predictably good results. It is not, however, considered by us to be the only way to achieve the expected goal. This is simply the technique with which we are most acquainted and comfortable.

Author's Preferred Surgical Technique

The patient is placed supine on the operating table and general anesthesia is used. The elbow is examined under anesthesia and then placed on an arm board. We use a tourniquet inflated to 250 mm Hg. Until 3 years ago, we performed elbow arthroscopy through an anterolateral portal prior to beginning the UCL reconstruction. We abandoned performing the elbow arthro-scopy because we did not change anything in our surgical technique based on the findings during the arthroscopy.

The procedure begins with a medial incision centered over the medial epicondyle approximately 10 cm in length. Identification of the medial antebrachial cutaneous nerve is performed, and it is protected using a vessel loop for retraction. The ulnar nerve is then dissected from the cubital tunnel and release of the nerve is taken proximally to the arcade of Struthers and distally into the flexor carpi ulnaris muscle mass (Fig. 34-4). The medial intermuscular septum is excised distally to prevent tenting of the nerve after transposition. The anterior band of the UCL is exposed by elevating the flexor muscle mass from the ligament at its attachment to the sublime tubercle (Fig. 34-5). The ligament is then incised longitudinally, from the apex of the sublime tubercle toward its origin on the medial epicondyle in line with the fibers (Fig. 34-6). This splitting of the native ligament allows direct visualization of the origin and insertion of the ligament, as well as excision of any bony osteophytes or previously avulsed bony fragments.

If valgus extension overload is also present, we perform a vertical incision in the posterior capsule proximal to the fibers of

Figure 34-4 Surgical exposure of the medial elbow, including isolation of the ulnar nerve. Note the preservation of the motor branch to the flexor musculature. At the time of ulnar nerve dissection, the medial intermuscular septum is excised.
Figure 34-7 The palmaris longus graft is harvested using two small incisions at the distal forearm and one incision at the level of the muscle-tendon junction.

Figure 34-5 The flexor-pronator mass is elevated off the underlying ulnar collateral ligament. This allows visualization of the entire length of the anterior band of the ligament. Note also the tear in the proximal portion of the ligament.

the posterior band. This exposes the olecranon tip for inspection and removal of any offending osteophytes. The osteophytes are removed with a small osteotome and a high-speed bur. The capsule is then closed with absorbable suture.

Graft harvest is then performed. We prefer the ipsilateral palmaris longus tendon if it is present and of sufficient size (Fig. 34-7). If it is not, then the contralateral gracilis tendon is our next choice. The palmaris is harvested with three small transverse incisions in the volar forearm with the most distal incision at the proximal wrist crease. Care should be taken to avoid harvesting the flexor carpi radialis or median nerve, which are in close proximity.

Next, the ulnar tunnels are drilled using a 9/64-inch drill bit (palmaris graft) or 5/32-inch drill bit (gracilis graft). The ulnar tunnels are drilled 3 to 4 mm distal to the articular surface. The first tunnel begins just at the posterior aspect of the sublime

Figure 34-6 The ulnar collateral ligament is split longitudinally to expose the underlying lateral elbow articulation. This allows the surgeon exposure of the undersurface of the ligament, which is the location of most pathology. Also, the visualization facilitates drilling of the humeral and ulnar tunnels.

Figure 34-6 The ulnar collateral ligament is split longitudinally to expose the underlying lateral elbow articulation. This allows the surgeon exposure of the undersurface of the ligament, which is the location of most pathology. Also, the visualization facilitates drilling of the humeral and ulnar tunnels.

tubercle and is directed laterally and slightly posteriorly. The second tunnel begins at the anterior aspect of the sublime tubercle and is directed posteriorly. The two tunnels are connected to each other with curved curets and irrigated. Two tunnels are then drilled in the medial epicondyle of the humerus, converging at the origin of the native UCL. The first tunnel is drilled proximally to distally, and the second medially to distally with a 1-cm bridge between the two tunnels. The tunnels are then curetted and irrigated. Suture loops are then passed through the three tunnels. The distal portion of the native ligament is closed with nonabsorbable suture to enhance the stability, leaving the proximal portion of the native ligament open to allow graft passage. The graft is brought on the table, and a tendon-gathering stitch is placed in each end of the graft in order to allow tensioning. One of the graft ends is passed through the ulnar tunnel using a suture loop. The ends of the graft are then passed in a figure-eight fashion through the humeral tunnels, and the proximal portion of the native ligament is closed (Fig. 34-8).

Figure 34-8 The graft is passed in figure-eight fashion through the ulnar and humeral tunnels.
Figure 34-9 The graft is tensioned with the elbow in 30 degrees of flexion and neutral rotation. The limbs of the graft are then tied to one another above the medial epicondyle of the humerus.

The graft is tensioned with the elbow in 30 degrees of flexion and the valgus stress on the elbow removed. While holding this position and holding the tension on the graft ends, which are crossed above the medial epicondyle, the graft is sutured to itself with multiple nonabsorbable sutures (Fig. 34-9). The limbs of the graft spanning the humeral-ulnar course of the ligament are then sutured to one another using permanent suture to add more tension to the graft (Fig. 34-10).

The ulnar nerve is transposed anteriorly using a fascial sling from the flexor-pronator muscle mass (Fig. 34-11). The cubital tunnel is closed and the split in the flexor carpi ulnaris fascia is closed distally with one stitch to prevent propagation of the split and herniation of the muscle. The skin is closed and the elbow placed in a well-padded posterior splint flexed to 90 degrees for 5 to 7 days. The patient then is placed in a hinged range-of-motion brace and follows a supervised rehabilitation program. The patient will begin a throwing program at 16 weeks, and will be able to return to competition at an average of nearly 9 months.

Figure 34-10 The graft is sewn to itself and the underlying native ulnar collateral ligament. This provides additional tension to the graft.

Figure 34-11 The ulnar nerve is transposed beneath a leash of flexor fascia in a subcutaneous fashion. After transposition, the cubital tunnel is closed to prevent the ulnar nerve from returning to its previous location.

Results

After nonoperative treatment of UCL injuries in overhead athletes, the return to play rate is 42%.14 UCL repair may have a better return to play rate (50% to 63%) than nonoperative treatment, but it does not approach the rate of return of reconstructive treatment.17,21 This decreased chance to return to play is especially true for the attenuated and partial ligament tears, which are not amenable to repair but could theoretically be imbricated. UCL reconstruction fares much better with reported return to play rates being 80% to 92%.11,12,22 The rate of return to play at the same or higher level is not as good for high school baseball players, averaging 74%. The reason for the lower rate of return to play in the high school athlete may be only secondary to other issues with adolescents such as loss of interest in the sport or decreased opportunity to play at the next level (e.g., a senior high school player being injured and not being recruited for college or drafted).23

POSTEROLATERAL ROTATORY INSTABILITY

Posterolateral rotatory instability was a phrase coined by O'Driscoll et al24 in 1991 after describing the clinical entity as we know it today. Since then, interest and knowledge of the topic has grown. It is thought that this condition usually arises after traumatic dislocation of the elbow and clinically presents along a wide spectrum of instability. The affected structure is the LCL complex of the elbow, with specific injury to the lateral UCL. The degree of injury to the lateral side of the elbow that is necessary to cause instability is currently still under investigation. As stated earlier in this chapter, elbow dislocations are relatively common injuries and yet this type of instability was only recognized in the past 2 decades. It is still unknown how common this condition is and what the predisposing factors are that cause instability after elbow dislocation. The percentage of elbow dislocations that later have posterolateral rotatory instability is still unknown.

Relevant Anatomy

As noted at the beginning of the chapter, the elbow joint is a very congruous joint with bony anatomy accounting for the

Figure 34-10 The graft is sewn to itself and the underlying native ulnar collateral ligament. This provides additional tension to the graft.

majority of the stability of the elbow. The LCL complex is thought to have four major components: lateral UCL, radial collateral ligament (RCL), annular ligament, and accessory LCL. It appears to have a Y-shaped configuration.25 Proximally, the complex originates as a broad band from the lateral humeral epicondyle.26 Some authors refer to this as the superior band.25 Distally, the ligament may continue as one band or split into two bands, the anterior band being the radial collateral ligament and the posterior band being the lateral UCL.25,26 The annular ligament stabilizes the proximal radioulnar joint and the accessory collateral ligament is a band from the ulna to the annular liga-ment.26 The insertion point of the lateral UCL is the supinator crest of the ulna.

Cadaveric studies have shown that the entire LCL complex provides stability to the elbow. Sectioning of the radial collateral ligament does cause an increase in external rotation when the elbow is passively flexed and extended and causes an increase in varus laxity with the elbow ranged from 10 to 120 degrees. However, subluxation did not occur when the radial collateral ligament was sectioned because the lateral UCL and the coronoid prevented subluxation in those situations. When the lateral UCL was sectioned, gross instability with joint subluxation occurred to rotation.25

The common extensor origin also provides some dynamic stability to the lateral side of the elbow. Maintenance of the integrity of the proximal radioulnar joint is also necessary for posterolateral rotatory instability to occur as both the radial head and the ulna rotate and subluxate. If the proximal radioul-nar joint is disrupted, then the ulna will not subluxate with the radial head, causing solely radial head instability.24,26,27 O'Driscoll et al also believe that the posterolateral capsule provides some stability.2,24

A study of 62 elbow dislocations and fracture-dislocations showed that 52% of injuries to the lateral UCL complex occurred as a proximal soft-tissue avulsion off the lateral humeral epicondyle. Twenty-nine percent sustained a midsub-stance rupture. Eight percent had a proximal bony avulsion that was large enough to repair by osteosynthesis and 2% had a similar injury off the ulna. Only 5% had distal soft-tissue avulsion off the ulna.2

Concomitant rupture of the common extensor origin was seen in 62% of fracture-dislocations and 80% of pure dislocations.2 Though these injuries were more severe than the average elbow injuries because they required treatment secondary to inability to obtain or maintain closed reduction, a study of elbow dislocations that were able to be reduced found that 14 of 18 elbows where the lateral side was explored showed injury to the common extensor origin.28 It is O'Driscoll's opinion that damage to the supporting structures on the lateral side of the elbow (RCL, common extensor origin, anterior and posterior capsules) may cause posterolateral rotatory instability in the situation where the lateral UCL is torn.

History

Most patients present to the office complaining of lateral elbow pain or discomfort combined with sensation of snapping, catching, or locking. They may be able to express the feeling that the elbow is slipping out of place with the forearm in supination and the elbow slightly flexed. Some more severe cases may present with the history of multiple dislocation episodes. Seventy-five percent of patients younger than 20 years old will have a history of traumatic dislocation. Older patients may have a history of varus/extension stress. Still others may have other history such as lateral epicondylar release or cubitus varus deformity from childhood trauma.7,26,29

Physical Examination

Primarily, the elbow should be palpated for tenderness and inspected for deformity and range-of-motion deficits. Testing for other types of instability including valgus instability should be performed. The pivot-shift maneuver should be done by standing at the head of the patient with the patient lying supine and the arm extended above his or her head. The forearm should be maximally supinated, the elbow should begin extended, then the axial load is applied, and the elbow is slowly flexed. Many patients will have pain or apprehension with this maneuver but may not have noticeable subluxation in the office. Often the subluxation is only felt with the patient under general anesthesia.26,29,30

Other provocative maneuvers include having the patient push up from a prone or wall position with the forearms in maximal pronation, then repeat with forearms maximally supinated. The patient will have symptoms with maximal supination. Another method is to have the patient push up from a seated position in a chair with the arm maximally supinated.26

Radiographic Studies

Standard practice is to obtain anteroposterior and lateral radiographs to look for evidence of previous trauma (e.g., heterotopic ossification, fracture deformity). Usually these radiographs are normal. Stress views can be obtained with the arm held in the pivot-shift position if the patient can tolerate it. Magnetic resonance imaging and computed tomography are of very limited value.7,26

Arthroscopy

Diagnostic arthroscopy can show evidence of posterolateral rotatory instability with two signs. First, the radial head can be demonstrated to subluxate when a pivot-shift maneuver is performed. Second, a drive-through sign can be seen by driving from the lateral gutter from the posterolateral portal and going into the ulnohumeral joint (i.e., driving through the radio-capitellar joint).26

Treatment

The first line of treatment is prevention of the problem. Although it is unknown how many elbow dislocations will later develop posterolateral rotatory instability, recognition of damage to lateral structures in a dislocated elbow and treating it accordingly are the first steps in prevention. If an elbow dislocation has evidence of damage to the lateral structures, then stabilizing the elbow with the forearm in pronation is helpful to prevent future lateral instability problems.27,31 Unfortunately, elbows with significant medial instability as well may not be stable in pronation.

Once chronic posterolateral rotatory instability is diagnosed, there are no conservative measures that appear to treat this condition. Surgical reconstruction of the LCL complex is the only treatment with known clinical success. The method of surgical treatment in chronic cases is usually ligament reconstruction with a tendon graft obtained from palmaris longus or a piece of triceps tendon.26,29,30 Occasionally, the ligament is only attenuated and can be imbricated.26,29 The reconstruction of the ligament complex can be performed via bone tunnels similar to the method of UCL reconstruction described earlier in the chapter or with anchors and bone tunnels.29,30 Recently arthroscopic capsular plication and ligament imbrication has been performed in some centers with some success.26

Rehabilitation and Results

The rehabilitation protocols are still evolving for this condition. Different surgeons are still using slightly different recommendations. Postoperatively, the elbow is immobilized at 70 to 90 degrees of flexion in full pronation from 2 to 6 weeks, depending on the surgeon. Full range of motion is begun from 3 to 6 weeks. Some surgeons require that the patient wear a hinged elbow brace until 3 months postoperatively for protection of the reconstruction. Return to play is allowed at 6 to 9 months postoperatively.26,29,30

Complications of the procedure that have been reported include recurrent instability, loss of motion, and injury to the lateral antebrachial cutaneous nerve.7,30 A potential risk to the posterior interosseous nerve is present, especially with the arthroscopic technique. There are very few studies with long-term follow-up or a significant patient sample size from which to report results. O'Driscoll et al24 found 90% satisfactory outcomes in the patients without significant degenerative changes. Olsen and Sojbjerg30 had 89% good to excellent results using their technique with suture anchors and bony trough in the ulna and a triceps graft; 83% returned to preinjury activity level and 94% were satisfied with the outcome.

It is important to note that the natural history of posterolateral rotatory instability is not known.7 If a patient is symptomatic but not surgically reconstructed, it is unknown whether degenerative changes or worsening of the symptoms will result.

ELBOW ARTHROSCOPY

Elbow arthroscopy is becoming a more common procedure as surgeons become more familiar with the techniques of arthroscopy and the indications for the use of arthroscopy in elbow surgery expand. The equipment necessary to perform elbow arthroscopy is similar to that of other arthroscopic procedures. A 4.0-mm, 30-degree arthroscope and a 2.7-mm short-barreled arthroscope are necessary to perform a thorough procedure. Standard 3.5- and 4.5-mm shavers and burs and graspers are often needed. A gravity or inflow pump and, depending on positioning, a bean bag, a traction setup, and a post are needed. In some cases, osteotomes and mallets may be used as well. Generally, an experienced arthroscopist has all these tools available.

Indications for performing elbow arthroscopy are constantly evolving. Well-accepted indications include diagnostic arthro-scopy, removal of loose bodies, excision of osteophytes, syn-ovectomy in patients with inflammatory arthropathies, treatment of osteochondritis desiccans of the capitellum, radial head excision, treatment of lateral epicondylitis, treatment of arthrofibrosis, septic arthritis, resection of plica, and assisting in fracture reduction.32 A newer indication includes treatment of posterolateral rotatory instability.26

Contraindications to elbow arthroscopy are significant distortion of normal anatomy, bony ankylosis, and severe fibrous ankylosis. Caution should be used in cases of previous ulnar nerve transposition, as anterior medial portals and some posterior portals place this structure at risk.

Positioning in the operating room is mostly surgeon preference. There are three main ways in which a patient may be positioned: supine with the arm on a table or suspended from a boom, prone with the arm over a post, or lateral decubitus with the arm over a post. Supine positioning has the advantage of ease of transitioning to an open procedure. The disadvantage to supine positioning is that the surgeon is often working with the instruments directed upward, which can be awkward, and the arm may swing back and forth while working. The advantages to prone positioning are the ease of working in the posterior compartment, the ease of manipulating the joint, and the improved scope mobility. Disadvantages to the prone position are the lack of flexion that can be obtained in that position, difficulty in working in the anterior compartment, and difficulty in repositioning the patient for a subsequent open procedure. Advantages to the lateral position are the relative ease to convert to supine, good posterior visualization, and other benefits similar to those of prone positioning. A disadvantage to the lateral position is some difficulty in accessing the anterior compartment.

The procedure starts with elevation of the extremity and inflation of the tourniquet. Ten to 15 milliliters of sterile fluid is injected into the elbow from the "soft spot" in the lateral elbow (between the lateral epicondyle, radial head, and olecranon). There are several portals that can be used in elbow arthroscopy. The anterolateral portal can be used as the initial portal. The location of the portal is 2 to 3 cm distal and 1 cm anterior to the lateral epicondyle.33 The structure that is most at risk with this portal placement is the radial nerve, which is 2 to 10mm away from the portal.34 The proximal lateral portal is also used as the initial portal by some because it is farther away from the neurovascular structures. The proximal lateral portal is located approximately 2 cm proximal to the lateral epicondyle along the anterior surface of the distal humerus.34 The posterior antebrachial cutaneous nerve may be the closest structure to the portal at 0 to 14 mm away and the radial nerve is on average 10 mm away.34 The anteromedial portal is generally made under direct visualization. The location is 2 cm distal and 2 cm anterior to the medial epicondyle.33 The most at-risk major structure there is the median nerve, which is 5 to 13 mm away (lateral) from the cannula.34 The proximal medial portal is thought to be safer than the anteromedial portal and is located 2 cm proximal to the medial epicondyle and just anterior to the intermuscular septum.35 Again, the median nerve is at risk but is farther away at 7 to 20 mm.34 The ulnar nerve is not at risk except for possible subluxating ulnar nerve or history of transposition. The direct lateral portal is located between the lateral epicondyle, radial head, and olecranon, in the soft spot.33 This is a safe portal. If work is going to be performed in the lateral compartment of the elbow, two portals need to be made laterally. One should be about 1 cm distal so there is enough room to work in this space. The posterolateral portal is placed under direct visualization with the elbow in 30 to 45 degrees of flexion. The portal should be 3 cm proximal to the olecranon tip at the lateral edge of the triceps tendon.33 This portal has relatively low risk. The direct posterior portal is placed under spinal needle localization. It may be placed either directly through the triceps tendon or just medial to it, 3 cm proximal to the olecranon tip. The ulnar nerve is at risk if the portal is placed medial to the tendon. Care must be taken to cut away from the nerve and use the nick-and-spread technique.33

Results and Outcomes

An early study of results following elbow arthroscopy showed that the best results followed loose body removal, with up to 89% of patients significantly improved, and the results for treatment of chondromalacia were less favorable.33,36 A follow-up study by Andrews et al37 confirmed that the best results occurred after treatment of mechanical problems such as loose bodies. Treatment of capitellar OCD has also been found to have good short-term results with 13 of 16 adolescent athletes returning to their sports after surgery.38 Treatment of osteo-phytes with posterior elbow impingement showed 100% good to excellent results in one study of 21 patients at nearly 3 years of follow-up.39 Treatment of arthrofibrosis, while beneficial, shows moderately impressive results with 79% rated as good to excellent; although the average flexion contracture was still more than 10 degrees postoperatively, the average gain of extension was 18 degrees.40 The results of arthrofibrosis surgery are good overall, but it is more risky to perform.

Complications

Reported complications of elbow arthroscopy include compartment syndrome, septic arthritis, superficial infection, drainage from portal sites, and neurovascular injuries. In one study, the most common immediate complication was transient nerve palsy; it occurred in 12 of 473 patients. Four were superficial radial nerve, five ulnar nerve, one posterior interosseous nerve, one anterior interosseous nerve, and one medial antebrachial cutaneous nerve palsies. All palsies resolved within 6 weeks except one, which resolved in 6 months. Factors that were found to increase risk included rheumatoid arthritis, contractures, and capsular releases. No permanent nerve injuries were found in 473 procedures. No compartment syndromes or hematomas occurred. The most common delayed complication was prolonged drainage from the portal site (defined as drainage for longer than 5 days), which occurred in 5% of patients. Increased risk factors for this drainage included not suturing the portals or using simple stitches. The anterolateral and direct lateral portals were the most common portals affected. Superficial infections occurred in 2% of patients. Septic arthritis occurred in nearly 1% of patients. This was increased in patients who had steroids injected into the elbow at the end of the procedure. Seven of 473 procedures had persistent loss of motion between 5 and 15 degrees.32

Reported severe nerve injuries include posterior interosseous nerve transection during capsulectomy, and complete tran-section of the median and radial nerves in a patient with post-traumatic elbow contracture.41,42 Kim also reported two transient median nerve palsies.43

Risk factors for neurovascular injuries include rheumatoid arthritis and arthrofibrosis. Rheumatoid arthritis increases the risk of injury secondary to the thin and friable capsule and loss of normal intra-articular landmarks. Arthrofibrosis increases risk secondary to decreased capsular distention and the process of capsular release as well as the increased complexity of the procedure. Kelly et al32 believe that the use of retractors in the anterior part of the elbow while performing capsular release and arthroscopic identification of the nerves decrease the risk of serious nerve injury.

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Cure Tennis Elbow Without Surgery

Cure Tennis Elbow Without Surgery

Everything you wanted to know about. How To Cure Tennis Elbow. Are you an athlete who suffers from tennis elbow? Contrary to popular opinion, most people who suffer from tennis elbow do not even play tennis. They get this condition, which is a torn tendon in the elbow, from the strain of using the same motions with the arm, repeatedly. If you have tennis elbow, you understand how the pain can disrupt your day.

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