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Optimizing Elbow Rehabilitation After Instability
Hand Clin 24 (2008) 27–38
Optimizing Elbow Rehabilitation After Instability Mike Szekeres, OT Reg (Ont)a,*, Shrikant J. Chinchalkar, BScOT, OTR, CHTa, Graham J.W. King, MD, MSc, FRCSCa,b a
Department of Hand Therapy, Hand and Upper Limb Centre, St. Joseph’s Health Care London, 268 Grosvenor Street, London, Ontario, Canada N6A 4L6 b Division of Orthopaedic Surgery, University of Western Ontario, London, Ontario, Canada
Rehabilitation of the unstable elbow is challenging because of the competing issues of maintaining articular congruency for soft tissue healing while at the same time preventing stiffness. The elbow is notoriously prone to develop stiffness because of capsular tissues, which tend to thicken and contract when exposed to trauma. Although the articulation is relatively congruous, acute and chronic instability of the elbow remain common clinical problems. The elbow is the key joint in the upper extremity because it provides the motion necessary to place the hand in space for function. Stiffness of the elbow is poorly tolerated and as a consequence early motion following elbow injuries is frequently used. In the setting of elbow instability it is critical that communication occur between the treating physician and therapist so that an optimal program can be developed specific to the circumstances of the patient’s pathoanatomy. The soundness of the internal fixation and ligament repairs must be specifically articulated to the treating therapist so that a program can be developed to provide early motion yet avoid persistent instability. Preservation of articular congruency and restoration of long-term stability is of paramount importance. Given a choice of adverse outcomes, a stiff stable elbow is easier to manage than an unstable mobile elbow. Managing a stiff stable elbow with modern techniques of arthroscopic or open elbow contracture release is
* Corresponding author. E-mail address: [email protected] (M. Szekeres).
reliable and has a lower complication rate than management of persistent elbow instability, particularly elbow instability combined with osseous injuries. Elbow anatomy and biomechanics The elbow consists of three bones: the distal humerus, proximal ulna, and radial head. Together these bones form the three articulations consisting of the ulnotrochlear, radiocapitellar, and proximal radioulnar joints. These articulations are stabilized by a thin anterior and posterior elbow capsule, which is prone to become markedly thickened following elbow trauma resulting in elbow stiffness. The medial collateral ligament (MCL) is an important valgus stabilizer of the elbow [1]. It consists of two major portions, the anterior and posterior bundle. The anterior bundle is the primary constraint to valgus instability throughout the arc of motion, particularly at higher angles of flexion. The MCL is not isometric, inserting just posterior to the axis of elbow flexion and extension resulting in reciprocal tightening in flexion and greater laxity in extension [2]. The posterior bundle inserts even more posterior to the axis of motion and therefore tends to be lax in extension and tight in flexion. In elbows lacking flexion, the posterior band of the MCL is lax and tends to contract, causing an important restriction to elbow flexion. The lateral collateral ligament (LCL) consists of three major portions. The annular ligament inserts on the anterolateral and posterolateral aspects of the proximal ulna at the radial notch.
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The lateral ulnar collateral ligament is attached to the lateral epicondyle and the sublime tubercle of the proximal ulna. The radial collateral ligament is situated more anterior than the lateral ulnar collateral ligament on the lateral epicondyle and blends with the annular ligament, which surrounds the radial head. The LCL resists varus and posterolateral rotational instability of the elbow [3]. Given that most activities of daily living place varus loads across the elbow, the LCL is considered to be more important than the MCL for normal function of the elbow joint [4]. The LCL is isometric throughout flexion because of its attachment site near the axis of motion. In addition to these stabilizing capsule ligamentous elements of the elbow, the osseous components are important to stability. The radial head is an important valgus stabilizer of the elbow, as is the anteromedial coronoid to varus stress of the elbow [5]. The radial head and coronoid act as a buttress to posterior subluxation of the elbow. Elbow instability associated with fractures is much more challenging to treat in that not only are the soft tissue components critical but reconstruction of the stabilizing osseous elements is also necessary.
Optimizing rehabilitation Rehabilitation of the unstable elbow is a challenging process that must take into account several biomechanical, physiologic, and patient-related factors. Successful rehabilitation of the elbow depends on close communication between the treating physician and therapist. Before initial assessment, the therapist must be aware of the rigidity of bony fixation achieved, the ligamentous stability, and the status of other soft tissues surrounding the joint, such as the joint capsule and dynamic stabilizers. The surgical details guide treatment because they determine the type of motion allowed, the safe arc of motion, the splint positioning, and the limitations for functional use of the upper extremity by the patient following surgery.
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stretching is effective when followed by passive and active range of motion (ROM) exercises. Edema and pain control Edema and pain are common problems following elbow injuries and surgery and limit elbow joint mobility. Compressive bandaging and elevation of the extremity above the heart level helps reduce edema and pain. Application of cold packs or compression/icing systems after exercises during the inflammatory phase of tissue healing helps in addressing these symptoms (Fig. 1). As the inflammatory phase subsides retrograde massage may be introduced to control pain and swelling. As muscle function increases with exercise, venous and lymphatic drainage are enhanced, which causes further reduction of edema and pain. Pain can present a significant obstacle during the rehabilitation process. The judicious use of analgesics and anti-inflammatories is important during the first 2 weeks after injury. Effective pain management is patient specific. As the surgeon adjusts medications to achieve improved pain control, the therapist adjusts the splinting and exercise programs. Patients who remain pain focused more than 3 weeks into rehabilitation should be reevaluated by the referring surgeon to ensure continued bony alignment. Patients are referred for a pain clinic evaluation if signs of complex regional pain syndrome (CRPS) develop during treatment. If there is no evidence of CRPS or radiographic changes, therapy is often modified
General rehabilitation principles There are several principles of rehabilitation that are generally accepted as being beneficial regardless of the type of elbow injury. Edema and pain control and early initiation of active motion improve short and long term results. Later in the rehabilitation process, the use of superficial heat for the purpose of preconditioning tissues for
Fig. 1. Compression and icing is used for reduction of edema and pain.
OPTIMIZING ELBOW REHABILITATION AFTER INSTABILITY
in these patients to increase active mobilization. Patients remove protective splints while sedentary during the day to encourage increased motion, and should exercise more frequently at home. These patients should attend therapy more frequently for encouragement, edema/pain management, exercise reviews, and splinting modifications. Passive stretching for stiffness Regardless of the type of elbow injury, residual stiffness is a common problem during the latter stages of rehabilitation. Patients who present with elbow contractures should initiate passive stretching as long as the osseous and ligamentous structures are sufficiently healed, typically 6 to 8 weeks following the injury or surgery. Therapy sessions nearly always begin with some form of superficial heating for 15 to 20 minutes to precondition the tissues to make them more amenable to stretching. Patients either use hot packs while stretching with a weight or elastic band, or immerse the arm in a whirlpool and perform active motion (Fig. 2). Once the tissues are preconditioned, patients are positioned supine and the therapist performs passive ROM (Fig. 3). Modifications are made to the stretching program based on the patient’s injury, instability pattern, current ROM, healing, and pain threshold. Joint distractions are followed by physiologic passive stretching and then active motion. Strengthening exercises are performed at the end of the therapy session. The spectrum of instability Elbow instability is a general term used to describe a broad spectrum of injuries. It may refer
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to anything from an acute traumatic dislocation to a chronic laxity resulting in transient joint subluxation [6]. Instability may be present secondary to coronoid or radial head fractures, or damage to the varus/valgus ligamentous stabilizers of the elbow. O’Driscoll and colleagues [7] described a spectrum of instability, ranging from subtle posterolateral rotatory subluxation to full posterior dislocation. In stage 1, the elbow subluxates in a posterolateral direction. Stage 2 includes incomplete (or perched) dislocation of the ulnohumeral joint with the tip of the coronoid resting on the trochlea. Stage 3 is subdivided into stage 3A and 3B. In stage 3A, the ulnohumeral joint is completely dislocated, but the anterior band of the MCL is preserved. In stage 3B, all collateral ligaments are disrupted in association with complete ulnohumeral dislocation. Dislocations represent between 11% and 28% of all elbow injuries and the elbow is the second most common joint dislocated among the adult population. Managing stage 3 instabilities requires attention to both the MCL and the LCL. Dislocation of the elbow is termed either simple or complex based on the plain radiographs or computed tomography. Simple dislocations involve soft tissue structures only [8,9], whereas complex dislocations have associated fractures of the radial head, coronoid, or distal humerus [10]. Simple dislocations are generally managed by closed reduction. Recurrence of simple elbow dislocations is uncommon because of the intrinsic stability of the joint, but if they occur despite appropriate splinting and rehabilitation they require surgical ligament repair. Complex dislocations require restoration of the fractured articular structures by open reduction and internal fixation along with the repairs of one or both of the collateral ligaments.
Fig. 2. (A, B) The use of hot packs or whirlpool preconditions tissues before stretching in therapy to make passive and active stretching more effective.
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Fig. 3. (A, B) Passive physiologic stretching for elbow flexion and extension.
Lateral injuries Biomechanics The lateral ulnar collateral ligament is the primary stabilizer against posterolateral rotatory instability and varus instability [7,11]. Because the ligament attaches at the axis of rotation, it is uniformly taut during elbow motion [3,12]. Several studies have shown that division of the radial collateral ligament and lateral ulnar collateral ligament causes a significant increase in varus and posterolateral rotational instability [3,13–15]. Posterolateral rotatory instability (O’Driscoll type 1) is the most common pattern of acute and chronic elbow instability and often occurs as a result of fall on an outstretched hand [16]. There have also been studies demonstrating that the radial head and coronoid process act as secondary posterolateral rotatory stabilizers of the elbow [17,18] Furthermore, the anteromedial coronoid is an important secondary constraint to varus stability of the elbow. Hotchkiss [19] coined the term ‘‘terrible triad’’ as an injury consisting of fracture of radial head and coronoid process associated with a posterolateral dislocation of the elbow joint. Cadaveric studies have demonstrated the importance of the position of forearm rotation and active muscle contraction in stabilizing collateral ligament deficiencies of the elbow [20,21]. Cohen and Hastings [22] reported that forearm pronation spontaneously reduces posterolateral rotatory instability when the lateral ligamentous complex is disrupted. Investigations following sectioning of the LCL have concluded that the elbow was most stable under active flexion with the forearm in pronation and least stable with the elbow moved passively and with the forearm in supination [23– 25]. Dunning and colleagues [26] identified that
active flexion with the forearm in pronation created a more normal motion pathway than in supination. Varus moments, such as abduction of the shoulder, should be avoided in the LCL-deficient elbow. Following LCL repair, maintaining the forearm in pronation and performing active motion keeps the extensor/supinator group of muscles tensioned, which contributes to the stability on the lateral side. The extensor muscles originating from the lateral epicondyle prevent the forearm unit rotating away in posterolateral direction [14]. Optimizing rehabilitation for lateral injury Posterolateral rotatory dislocations are the most common form of elbow instability and occur as a result of a fall on an outstretched hand with the forearm in supination. The fall causes an axial load in the valgus direction and produces a sequential disruption of the stabilizing structures starting laterally and progressing medially [16]. Complete dislocations of the elbow without associated fractures always tear both the MCL and LCL; however, the extent of injury is typically more severe laterally and this often dictates the appropriate therapy. Most isolated elbow dislocations can be successfully managed nonoperatively following a closed reduction under sedation. Patients who have fracture-dislocations can be managed nonoperatively if the fracture fragments are small and do not interfere with motion. Larger displaced coronoid and radial head fractures are usually treated operatively with open reduction and internal fixation. For patients who have associated severe radial head fractures, prosthetic replacement is preferred to excision to minimize secondary complications of valgus and posterolateral rotatory instability [27–30]. If surgery is performed, the LCL is usually repaired; however,
OPTIMIZING ELBOW REHABILITATION AFTER INSTABILITY
the MCL frequently is not. The quality of the ligament repair achieved is variable depending on the extent of injury. Following either nonsurgical or surgical reduction of an elbow dislocation, joint stability and the stable arc of motion are assessed intraoperatively with an image intensifier. Postreduction lateral elbow radiographs are performed to check for residual joint subluxation in the initial splint. Patients who have repair of anteromedial coronoid fractures with or without LCL repairs also require careful rehabilitation to protect the LCL during healing. Sometimes the LCL is sectioned by the surgeon and subsequently repaired during the management of capitellum fractures, radial head fractures, when performing elbow contracture releases for stiffness, and following total elbow arthroplasty. Finally, patients who have chronic varus or posterolateral rotatory instability are usually managed with a reconstruction of the lateral ulnar collateral ligament, which also needs protection during rehabilitation to avoid stretching out or failure of the graft during healing. Discussion between the surgeon and therapist is essential to plan the optimal rehabilitation program, which should be tailored to the intraoperative findings and the evaluation of stability following joint reduction or ligament repair. The progression of therapy is based on the stability of the elbow and physiologic changes that occur with healing. The goal of therapy is to reduce pain and swelling, restore elbow and forearm motion, and maintain elbow stability. Early therapeutic intervention is critical to regaining elbow motion and function. Patient education is of vital importance to ensure that the patient understands the injury or surgery, the splinting and exercise routine, the importance of compliance with the therapeutic program, and the precautions that must be observed to prevent recurrent instability. It is preferred that the patients are seen in therapy between 1 and 3 days following reduction of the elbow. The progression of therapy can be divided into three phases. Phase I: day 1 to 4 weeks LCL deficiencies are best splinted with the forearm in pronation and the elbow at 90 degrees of flexion. This position can be achieved by using a posterior thermoplastic splint positioning the forearm in pronation and the wrist in slight extension (Fig. 4). Positioning the forearm and wrist in this position reduces the stress on the lateral soft tissue structures. Because the anterior joint
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Fig. 4. A resting splint in pronation for lateral-sided injury.
capsule is torn in patients who have dislocations, splinting at greater than 90 degrees of elbow flexion is likely to produce elbow flexion contractures. The splint is worn continuously for a period of 3 to 4 weeks except for exercise periods and skin care. Patients are cautioned about the gravitational force on the lateral structures of the elbow joint while performing overhead exercises [6], while sleeping, or by laying the arm across the chest. Internal rotation of the shoulder results in a varus force being applied across the elbow, loading the deficient LCL and possibly causing lateral joint gapping. External rotation of the shoulder applies a rotational torque across the elbow, which can result in the radial head subluxing posterolaterally. A nighttime posterior elbow extension splint with the forearm maintained in pronation may be introduced at 3 weeks if patients stiffen quickly and are having difficulty extending the elbow. The splint is progressively adjusted as the patient gains elbow extension. Exercise program Exercises are commenced within 1 week following the reduction of the elbow. The program starts with active assisted or overhead exercises initially, progressing to active and then resisted exercises based on the healing stages and the stability of the elbow joint. Several studies have identified the adverse effects of immobilization following simple or complex elbow dislocations. Flexion contractures, pain, and loss of function are common complications of immobilization [31–35]. Early mobilization of the elbow joint following reduction produces a functional arc of motion in most patients [36].
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Early mobilization depends on the following factors: joint stability following reduction, whether an extension block is needed for stable arc of motion, and the presence of a drop sign [37]. If the elbow joint is stable after reduction, active elbow ROM exercises with the forearm in pronation are performed 10 to 15 times every 2 to 3 hours. Forearm rotation exercises are only performed with the elbow in 90 degrees or greater flexion. In the presence of a drop or sag sign, (a radiographic gap between the ulna and humerus) it is important that isometric exercises of triceps and brachialis are performed while in the splint at regular intervals to reduce ulnohumeral separation (Fig. 5) [38]. In addition to the isometric exercises, overhead exercises consisting of elbow flexion and extension (with forearm pronated) and forearm rotation with the elbow at 90 degrees of flexion are effective in reducing gravitational force while allowing stable arc of motion (Fig. 6) [6]. The overhead exercises are performed in supine with the shoulder flexed to 90 degrees and neutral rotation. The effect of gravity and activation of the triceps provides stability to the elbow joint as the motion is performed [6]. If the surgeon believes that the elbow is unstable, active extension of the elbow is initially limited to prevent recurrent dislocation and increased 10 to 15 degrees per week as healing progresses. The entire exercise program is customized to the patient’s specific pathoanatomy and residual instability depending on the various factors described earlier. Passive stretching should be avoided in the early phases of healing because of the theoretic risk for causing heterotopic ossification and the potential for inducing instability.
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Shoulder, wrist, and digital active motion exercises are performed throughout the rehabilitation program. Once pain and swelling are under control, resisted wrist and digital extensor exercises are added to the previous program if the muscle origins are known to be intact. Strengthening of the extensor muscles originating from the lateral epicondyle further increases the stability of the elbow joint [22]. Phase II: 4 to 6 weeks Joint stability is often achieved by 4 to 6 weeks following trauma or surgery. The goal of this stage of elbow rehabilitation is to maximize elbow and forearm range of motion while maintaining elbow stability and maximizing the strength of the lateral muscles. On confirmation of joint stability from the referring surgeon, the posterior elbow flexion splint is discontinued. A collar and cuff are worn while out of the house and while active. Edema is often not a concern at this stage. Heat is applied before exercise to increase the compliance of the tissues and allow a greater arc of motion. Flexion–extension exercises are performed with the forearm in neutral position 20 to 25 times on an hourly basis. Forearm rotation exercises are still performed, however, with the elbow in 90 degrees of flexion. Wrist and digital extensor strengthening with greater resistance is continued along with grip strengthening exercises. At this stage patients are encouraged to perform light ADL as long as the combined motion of elbow extension and forearm supination is avoided. A well-written home program and review of precautions enhances patient compliance. Flexion contractures are a common complication following elbow trauma. A nighttime elbow extension splint molded to the anterior aspect of the elbow is helpful to gain extension (Fig. 7). This splint is adjusted as the extension gains are made. Phase III: 6 to 12 weeks
Fig. 5. The drop sign showing a radiographic gap between the humerus and ulna.
Concerns regarding joint stability in this phase are minimal. The precautions of limiting motion of the elbow and forearm are lifted in consultation with the referring surgeon. The goal of therapy in this phase is to increase mobility, strength, endurance, and overall upper extremity function. Once the ligamentous and osseous healing is secure progressive elbow strengthening using weights and elastic bands is incorporated into the program. Strengthening of elbow flexors with the forearm in pronation are performed for the
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Fig. 6. (A, B) Overhead flexion and extension in supine position. The contralateral arm is used for support.
first 2 weeks. This method of strengthening minimizes an excessive load on the lateral structures of the elbow, thus reducing the chance of recurrent elbow instability. Elbow flexor strengthening with the forearm in supination is initiated later. Triceps strengthening must also be incorporated during the strengthening program. Shoulder, forearm, wrist, and hand strengthening are of critical importance at this phase of elbow rehabilitation. Contracture formation causing elbow joint stiffness is a common complication following elbow dislocations. Application of heat and stretch, passive range of motion, joint
Fig. 7. The nighttime elbow extension splint.
mobilization, and static progressive splinting have added benefits in restoring elbow motion.
Medial injuries Biomechanics The anterior bundle of the MCL is considered to be the primary constraint to valgus instability throughout the arc of elbow motion [5,20,39,40]. The posterior bundle of the MCL provides additional stability to the ulnohumeral joint but only during flexion because it attaches to the medial epicondyle even more posterior to the flexion axis of the elbow. The secondary stabilizer for valgus loading is the radial head. Radial head excision with MCL deficiency has been shown to markedly reduce valgus stability [11,41]. The radial head provides a mechanical buttress against excess valgus as it engages the capitellum under valgus loading. Other valgus stabilizers include the anterior joint capsule and the muscles crossing the elbow. The anterior joint capsule provides a small amount of stability when the elbow is in full extension; however, the capsule is typically disrupted in patients who have elbow dislocations [11]. The anterior joint capsule becomes
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redundant when the elbow is flexed and provides no contribution to the stability of the elbow joint in this position [11]. The muscles crossing the elbow contribute to dynamic stability of the joint. Park and Ahmad [42] studied the contribution of the flexor-pronator mass to valgus stability of the elbow in cadaveric models. They found the primary dynamic constraints to be the flexor carpi ulnaris and flexor digitorum superficialis muscles. This finding has implications for rehabilitation. Early strengthening of these muscle groups following MCL injury is not only safe to perform but may also ultimately help to contribute to dynamic valgus stability of the elbow. The position of the forearm also has an effect on elbow stability after medial-sided injuries. Safran and colleagues [20] recently studied the effect of forearm rotation of valgus laxity of the elbow. They concluded that valgus laxity was greatest with the forearm in neutral forearm rotation, and greater stability was achieved with either full pronation or full supination. Other research has shown forearm supination to be the most stable for resisting valgus load [39,43]. Armstrong and colleagues [39] performed an in vitro biomechanical study of the MCL-deficient elbow in 2000 and demonstrated that active motion and forearm supination stabilized the MCL-deficient elbow. They hypothesized that forearm supination creates an external moment on the ulna that allows the medial side of the elbow to close, effectively stabilizing the MCL-deficient elbow. Another hypothesis for the increased stability on the medial side offered by forearm supination is the mechanics of the distal radioulnar joint [40]. When pronated, a lateral translatory motion of the ulna at the distal radioulnar joint occurs. The ulna translates medially in supination. This translatory motion of the ulna can effectively open the ulnohumeral joint when the integrity of the collateral ligaments is compromised. Supination also increases tension on the flexor/pronator group, which has been shown to contribute to dynamic stability for valgus loading [42]. Optimizing rehabilitation for medial injury MCL injury can occur following an acute traumatic event or develop as a chronic condition in throwing athletes or individuals who place repeated valgus loads on the elbow. MCL disruption can occur in isolation following a fall or combined with an elbow dislocation or fracture of the radial head. Repair of the MCL in patients
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who have terrible triad injuries of the elbow is frequently not performed if a stable repair of the coronoid, radial head, and LCL is achieved. In patients who have a secure LCL repair, rehabilitation protocols should be developed in conjunction with the therapist to protect the unrepaired MCL to ensure optimal healing. Reconstruction of the MCL is often necessary in chronic situations to facilitate competitive throwing athletes to return to activity and requires specialized rehabilitation protocols to allow them to return to highlevel sports. Regardless of whether the MCL is repaired following an acute traumatic event or reconstructed for a chronic athletic injury, rehabilitation must be geared toward maximizing motion and muscular strength without compromising stability. Phase I: day 1 to 4 weeks Patients are typically referred to therapy within 1 week following injury or surgery. The referral must indicate the safe arc of motion as assessed intraoperatively along with any associated fractures or soft tissue injuries. Patients are splinted with the elbow at 90 degrees and holding the forearm in maximum supination. Because the MCL lies close to the axis of elbow motion, holding the elbow at 90 degrees does not place excessive stress on the anterior portion of the MCL during healing. Placement of the elbow at 90 degrees does place slight stress on the posterior band of the MCL. This stress is beneficial because the posterior band tends to scar down and shorten following trauma and immobilization and may prevent achieving end-range flexion. Patients are educated about the injury and precautions on the first day of therapy. Aggressive edema control is instituted immediately as discussed previously. Patients remove the splint and perform exercises every 2 hours, and are instructed to use ice after every other exercise session. Superficial cold combined with compression using a cryo-cuff or other device is also effective for edema control. Exercise sessions are performed with the arm in vertical orientation with the patient in a seated position. We use this position because it has been shown to be safe when treating elbows with valgus instability. Patients perform active flexion and extension in maximum supination. Forearm rotation is performed with the elbow flexed past 90 degrees. Active motion is performed to create a joint reaction force from muscular contraction,
OPTIMIZING ELBOW REHABILITATION AFTER INSTABILITY
which effectively maintains the elbow in alignment during exercises. Isometric contraction of the elbow flexors and extensors are performed every hour while in the splint to facilitate elbow joint congruity and maintain muscular strength during this period of disuse. Phase II: 3 to 6 weeks Regaining terminal extension can occasionally be difficult, as is the case with most rehabilitation programs following elbow trauma. Our expectations for extension in most situations are that the patient can extend to 40 degrees in the first postoperative week and make weekly gains of 10 degrees per week unless severe instability is present. If the elbow is deemed to be stable in consultation with the treating surgeon and the patient fails to reach these goals, nighttime extension splinting in supination is added to the program at 3 to 6 weeks. The extension splint is monitored weekly and adjusted if necessary to accommodate increases in extension. The resting splint is removed and gentle resistance is added for gripping and for resisted ulnar deviation/flexion of the wrist while holding the elbow in flexion during therapy sessions. Early initiation of strengthening of the flexor/pronator group in this fashion may help contribute to longterm stability against valgus stress at the elbow. The remainder of this phase from a therapy perspective involves facilitation of ongoing reduction in edema, reinforcement of the home exercise program and precautions, initiation of the use of heat before exercise to increase tissue elasticity, and scar management.
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flexion turnbuckle must be used because it transfers a precise rotational component to the joint and avoids painful compression (Fig. 8) [44]. These splints should provide a low-load, prolonged stretch to the elbow. We recommend at least three sessions of splinting per day, with each session lasting between 30 minutes to 1 hour. Any symptoms of ulnar neuropathy during splint use are a relative contraindication to its use. Patients are educated in this regard during splint fabrication. In-line progressive resistive exercise for elbow flexion and extension with the forearm in supination is initiated at week 8. Valgus loading of any kind is avoided until week 12. Considerations for throwing athletes The medial side of the elbow is susceptible to injury in athletes because of the repetitive valgus force placed on the elbow while throwing. The rehabilitation goals for athletes are similar to the rest of the population: decrease edema, restore full motion, maintain stability, and regain muscular strength. The high demands placed on the elbow after injury or surgery in repetitive valgus loading must be taken into account at the time of the operation and during the rehabilitation process. Flexion contractures are a common complication following any elbow injury or operation. A small flexion contracture of 10 to 20 degrees often presents no functional limitation for most patients. Any amount of elbow flexion contracture can present significant disability for high-level
Phase III: 6 to 12 weeks Protective splinting is discontinued and patients begin using their injured upper extremity at week six as long as any associated fractures show radiographic evidence of early union. Passive range of motion for flexion and extension is initiated if residual limitations in range of motion persist. The posterior band of the MCL can adaptively shorten and scar after trauma, limiting flexion. In cases in which regaining terminal flexion is not accomplished through active and passive stretching, a static progressive flexion cuff or turnbuckle splint can be used to supplement the patient’s home exercise program. The flexion cuff may be used for patients who have greater than 110 degrees of elbow flexion. For patients who have very stiff elbows, the static progressive
Fig. 8. Static progressive splints for elbow flexion. The turnbuckle splint with the hinge must be used for patients who have very stiff elbows to minimize compression forces on the elbow joint.
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athletes, however. We prefer the use of a hinged brace in supination for these patients. The brace is initially set to allow motion from 40 to 110 degrees postoperatively (Fig. 9). The brace is adjusted weekly to allow a 15-degree increase in ROM in both directions. Patients remove the splint to perform active wrist, digit, and shoulder ROM. Active forearm rotation is performed with the elbow held in maximum flexion. The other main difference between throwing athletes and the remainder of the population is the progression of strengthening. Isometric in-line strengthening is initiated at week 4. Active resisted exercise is initiated at week 8, but remains in-line (no valgus loading) until week 12 to 14. Patients then begin a formal throwing program, as outlined by Wilk and colleagues [45], in week 16. This program consists of progressive long toss, followed by flat ground throwing, and finally pitching off a mound. Serial increases in effort begin once the long toss portion of the program is complete. Patients must be closely monitored by team staff and trainers to ensure that patients are pain free to prevent overexertion by overzealous athletes who are eager to return to sports. Typically pitchers do not return to high-level throwing for 1 year following an MCL reconstruction, and may improve velocity and ball control for up to 2 years. Optimizing rehabilitation for type 3 elbow dislocations The primary goal of therapy following reduction of elbow dislocation is to serially increase ROM while maintaining the reduction and preventing undue stress on the collateral ligaments.
Fig. 9. The hinged, locking elbow brace holding the forearm in supination.
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All patients are initially splinted in a posterior elbow splint holding the joint in 90 degrees of flexion for 5 to 7 days. They then begin protected active motion. If the elbow is stable once reduced, then unrestricted active motion is permitted. If instability is an issue, then full flexion is permitted but extension of the elbow past 60 degrees is avoided. Patients perform elbow flexion and extension exercises while supine in the overhead position as previously discussed for lateral injuries. Extension is increased by approximately 15 degrees per week. The position of the forearm in supination, pronation, or in neutral while performing extension depends on which ligaments are damaged. Neutral position of the forearm is used when both sides of the elbow remain unstable. Nighttime extension splinting is added to the program if patients fail to achieve weekly goals for extension. Passive stretching of the elbow should not be performed until after week six to ensure that the ligamentous stability is no longer an issue and that no heterotopic bone has formed. Aggressive stretching before week six may lead to greater stiffness, pain, instability, and loss of functional use. Protective splinting is discontinued at week six except for heavier activities of daily living. Passive range of motion is initiated at this point to address any motion limitations. Light progressive strengthening exercises are initiated at week eight and progressed as tolerated.
Summary Recent biomechanical studies have shown that following MCL transection active mobilization of the elbow in supination is beneficial, whereas passive mobilization and pronation tend to cause greater instability. Similarly, for patients who have LCL insufficiency, varus loads need to be avoided and pronation of the forearm has been demonstrated to be helpful in maintaining stability. These latter two facts are critical elements to developing a rehabilitation program for patients who have both acute and chronic instability of the elbow. Optimizing elbow rehabilitation after instability presents numerous challenges. The primary challenge is to find the balance between early motion for prevention of stiffness and maintaining stability. Contractures of the elbow joint develop if the elbow is immobilized. Early mobilization and splinting of the elbow following injury predictably leads to superior results as long
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as there is close communication between the surgeon and therapist outlining the pathoanatomy and safe arc of elbow motion assessed intraoperatively.
[18]
[19]
References [1] Morrey BF, Tanaka S, An KN. Valgus stability of the elbow. A definition of primary and secondary constraints. Clin Orthop Relat Res 1991;265: 187–95. [2] O’Driscoll SW, Jaloszynski R, Morrey BF, et al. Origin of the medial ulnar collateral ligament. J Hand Surg [Am] 1992;17(1):164–8. [3] Olsen BS, Vaesel MT, Sojbjerg JO, et al. Lateral collateral ligament of the elbow joint: anatomy and kinematics. J Shoulder Elbow Surg 1996;5(2 Pt 1): 103–12. [4] King GJ, Morrey BF, An AK. Stabilizers of the elbow. J Shoulder Elbow Surg 1993;2:165. [5] Hotchkiss RN, Weiland AJ. Valgus stability of the elbow. J Orthop Res 1987;5(3):372–7. [6] Wolff AL, Hotchkiss RN. Lateral elbow instability: nonoperative, operative, and postoperative management. J Hand Ther 2006;19(2):238–43. [7] O’Driscoll SW, Morrey BF, Korinek S, et al. Elbow subluxation and dislocation. A spectrum of instability. Clin Orthop Relat Res 1992;(280):186–97. [8] Hildebrand KA, Patterson SD, King GJ. Acute elbow dislocations: simple and complex. Orthop Clin North Am 1999;30(1):63–79. [9] Sheps DM, Hildebrand KA, Boorman RS. Simple dislocations of the elbow: evaluation and treatment. Hand Clin 2004;20(4):389–404. [10] Tashjian RZ, Katarincic JA. Complex elbow instability. J Am Acad Orthop Surg 2006;14(5):278–86. [11] An KN, Morrey BF. Biomechanics of the elbow. In: Morrey BF, editor. The elbow and its disorders. 3rd edition. Philadelphia: WB Saunders; 2000. p. 43–60. [12] Olsen BS, Sojbjerg JO, Dalstra M, et al. Kinematics of the lateral ligamentous constraints of the elbow joint. J Shoulder Elbow Surg 1996;5(5):333–41. [13] Sojbjerg JO, Helmig P, Kjaersgaard-Andersen P. Dislocation of the elbow: an experimental study of the ligamentous injuries. Orthopedics 1989;12(3): 461–3. [14] Olsen BS, Sojbjerg JO, Nielsen KK, et al. Posterolateral elbow joint instability: the basic kinematics. J Shoulder Elbow Surg 1998;7(1):19–29. [15] Deutch SR, Olsen BS, Jensen SL, et al. Ligamentous and capsular restraints to experimental posterior elbow joint dislocation. Scand J Med Sci Sports 2003; 13(5):311–6. [16] O’Driscoll SW. Elbow instability. Hand Clin 1994; 10(3):405–15. [17] Schneeberger AG, Sadowski MM, Jacob HA. Coronoid process and radial head as posterolateral
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rotatory stabilizers of the elbow. J Bone Joint Surg Am 2004;86-A(5):975–82. Ring D, Jupiter JB, Zilberfarb J. Posterior dislocation of the elbow with fractures of the radial head and coronoid. J Bone Joint Surg Am 2002;84-A(4): 547–51. Hotchkiss RN. Fractures and dislocations of the elbow. In: Rockwood CA, Green DP, Bucholz RW, et al, editors. Rockwood and Green’s fractures in adults. vol 1. 4th edition. Philadelphia: LippincottRaven; 1996. p. 929–1024. Safran MR, McGarry MH, Shin S, et al. Effects of elbow flexion and forearm rotation on valgus laxity of the elbow. J Bone Joint Surg Am 2005;87(9): 2065–74. Pomianowski S, O’Driscoll SW, Neale PG, et al. The effect of forearm rotation on laxity and stability of the elbow. Clin Biomech (Bristol, Avon) 2001; 16(5):401–7. Cohen MS, Hastings H 2nd. Rotatory instability of the elbow. The anatomy and role of the lateral stabilizers. J Bone Joint Surg Am 1997;79(2):225–33. King GJ, Dunning CE, Zarzour ZD, et al. Singlestrand reconstruction of the lateral ulnar collateral ligament restores varus and posterolateral rotatory stability of the elbow. J Shoulder Elbow Surg 2002; 11(1):60–4. Dunning CE, Zarzour ZD, Patterson SD, et al. Ligamentous stabilizers against posterolateral rotatory instability of the elbow. J Bone Joint Surg Am 2001;83-A(12):1823–8. Dunning CE, Zarzour ZD, Patterson SD, et al. Muscle forces and pronation stabilize the lateral ligament deficient elbow. Clin Orthop 2001;(388):118–24. Dunning CE, Duck TR, King GJ, et al. Simulated active control produces repeatable motion pathways of the elbow in an in vitro testing system. J Biomech 2001;34(8):1039–48. Moro JK, Werier J, MacDermid JC, et al. Arthroplasty with a metal radial head for unreconstructable fractures of the radial head. J Bone Joint Surg Am 2001;83-A(8):1201–11. King GJ. Management of comminuted radial head fractures with replacement arthroplasty. Hand Clin 2004;20(4):429–41. Beingessner DM, Dunning CE, Gordon KD, et al. The effect of radial head excision and arthroplasty on elbow kinematics and stability. J Bone Joint Surg Am 2004;86-A(8):1730–9. Hall JA, McKee MD. Posterolateral rotatory instability of the elbow following radial head resection. J Bone Joint Surg Am 2005;87(7):1571–9. Broberg MA, Morrey BF. Results of treatment of fracture-dislocations of the elbow. Clin Orthop Relat Res 1987;216:109–19. Azmi I, Razak M, Hyzan Y. The results of treatment of dislocation and fracture–dislocation of the elbowda review of 41 patients. Med J Malaysia 1998;(53 Suppl A):59–70.
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[33] Lansinger O, Karlsson J, Korner L, et al. Dislocation of the elbow joint. Arch Orthop Trauma Surg 1984;102(3):183–6. [34] Mehlhoff TL, Noble PC, Bennett JB, et al. Simple dislocation of the elbow in the adult. Results after closed treatment. J Bone Joint Surg Am 1988; 70(2):244–9. [35] Royle SG. Posterior dislocation of the elbow. Clin Orthop Relat Res 1991;(269):201–4. [36] Ross G, McDevitt ER, Chronister R, et al. Treatment of simple elbow dislocation using an immediate motion protocol. Am J Sports Med 1999;27(3): 308–11. [37] Coonrad RW, Roush TF, Major NM, et al. The drop sign, a radiographic warning sign of elbow instability. J Shoulder Elbow Surg 2005;14(3):312–7. [38] Amis AA, Dowson D, Wright V. Elbow joint force predictions for some strenuous isometric actions. J Biomech 1980;13(9):765–75. [39] Armstrong AD, Dunning CE, Faber KJ, et al. Rehabilitation of the medial collateral ligament-deficient
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elbow: an in vitro biomechanical study. J Hand Surg [Am] 2000;25(6):1051–7. Chinchalkar SJ, Szekeres M. Rehabilitation of elbow trauma. Hand Clin 2004;20(4):363–74. King GJ, Zarzour ZD, Patterson SD, et al. An anthropometric study of the radial head: implications in the design of a prosthesis. J Arthroplasty 2001; 16(1):112–6. Park MC, Ahmad CS. Dynamic contributions of the flexor-pronator mass to elbow valgus stability. J Bone Joint Surg Am 2004;86-A(10):2268–74. Beingessner DM, Dunning CE, Stacpoole RA, et al. The effect of coronoid fractures on elbow kinematics and stability. Clin Biomech (Bristol, Avon) 2007; 22(2):183–90. Szekeres M. A biomechanical analysis of static progressive elbow flexion splinting. J Hand Ther 2006; 19(1):34–8. Wilk KE, Reinold MM, Andrews JR. Rehabilitation of the thrower’s elbow. Tech Hand Up Extrem Surg 2003;7(4):197–216.
Optimizing Elbow Rehabilitation After Instability Mike Szekeres, OT Reg (Ont)a,*, Shrikant J. Chinchalkar, BScOT, OTR, CHTa, Graham J.W. King, MD, MSc, FRCSCa,b a
Department of Hand Therapy, Hand and Upper Limb Centre, St. Joseph’s Health Care London, 268 Grosvenor Street, London, Ontario, Canada N6A 4L6 b Division of Orthopaedic Surgery, University of Western Ontario, London, Ontario, Canada
Rehabilitation of the unstable elbow is challenging because of the competing issues of maintaining articular congruency for soft tissue healing while at the same time preventing stiffness. The elbow is notoriously prone to develop stiffness because of capsular tissues, which tend to thicken and contract when exposed to trauma. Although the articulation is relatively congruous, acute and chronic instability of the elbow remain common clinical problems. The elbow is the key joint in the upper extremity because it provides the motion necessary to place the hand in space for function. Stiffness of the elbow is poorly tolerated and as a consequence early motion following elbow injuries is frequently used. In the setting of elbow instability it is critical that communication occur between the treating physician and therapist so that an optimal program can be developed specific to the circumstances of the patient’s pathoanatomy. The soundness of the internal fixation and ligament repairs must be specifically articulated to the treating therapist so that a program can be developed to provide early motion yet avoid persistent instability. Preservation of articular congruency and restoration of long-term stability is of paramount importance. Given a choice of adverse outcomes, a stiff stable elbow is easier to manage than an unstable mobile elbow. Managing a stiff stable elbow with modern techniques of arthroscopic or open elbow contracture release is
* Corresponding author. E-mail address: [email protected] (M. Szekeres).
reliable and has a lower complication rate than management of persistent elbow instability, particularly elbow instability combined with osseous injuries. Elbow anatomy and biomechanics The elbow consists of three bones: the distal humerus, proximal ulna, and radial head. Together these bones form the three articulations consisting of the ulnotrochlear, radiocapitellar, and proximal radioulnar joints. These articulations are stabilized by a thin anterior and posterior elbow capsule, which is prone to become markedly thickened following elbow trauma resulting in elbow stiffness. The medial collateral ligament (MCL) is an important valgus stabilizer of the elbow [1]. It consists of two major portions, the anterior and posterior bundle. The anterior bundle is the primary constraint to valgus instability throughout the arc of motion, particularly at higher angles of flexion. The MCL is not isometric, inserting just posterior to the axis of elbow flexion and extension resulting in reciprocal tightening in flexion and greater laxity in extension [2]. The posterior bundle inserts even more posterior to the axis of motion and therefore tends to be lax in extension and tight in flexion. In elbows lacking flexion, the posterior band of the MCL is lax and tends to contract, causing an important restriction to elbow flexion. The lateral collateral ligament (LCL) consists of three major portions. The annular ligament inserts on the anterolateral and posterolateral aspects of the proximal ulna at the radial notch.
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The lateral ulnar collateral ligament is attached to the lateral epicondyle and the sublime tubercle of the proximal ulna. The radial collateral ligament is situated more anterior than the lateral ulnar collateral ligament on the lateral epicondyle and blends with the annular ligament, which surrounds the radial head. The LCL resists varus and posterolateral rotational instability of the elbow [3]. Given that most activities of daily living place varus loads across the elbow, the LCL is considered to be more important than the MCL for normal function of the elbow joint [4]. The LCL is isometric throughout flexion because of its attachment site near the axis of motion. In addition to these stabilizing capsule ligamentous elements of the elbow, the osseous components are important to stability. The radial head is an important valgus stabilizer of the elbow, as is the anteromedial coronoid to varus stress of the elbow [5]. The radial head and coronoid act as a buttress to posterior subluxation of the elbow. Elbow instability associated with fractures is much more challenging to treat in that not only are the soft tissue components critical but reconstruction of the stabilizing osseous elements is also necessary.
Optimizing rehabilitation Rehabilitation of the unstable elbow is a challenging process that must take into account several biomechanical, physiologic, and patient-related factors. Successful rehabilitation of the elbow depends on close communication between the treating physician and therapist. Before initial assessment, the therapist must be aware of the rigidity of bony fixation achieved, the ligamentous stability, and the status of other soft tissues surrounding the joint, such as the joint capsule and dynamic stabilizers. The surgical details guide treatment because they determine the type of motion allowed, the safe arc of motion, the splint positioning, and the limitations for functional use of the upper extremity by the patient following surgery.
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stretching is effective when followed by passive and active range of motion (ROM) exercises. Edema and pain control Edema and pain are common problems following elbow injuries and surgery and limit elbow joint mobility. Compressive bandaging and elevation of the extremity above the heart level helps reduce edema and pain. Application of cold packs or compression/icing systems after exercises during the inflammatory phase of tissue healing helps in addressing these symptoms (Fig. 1). As the inflammatory phase subsides retrograde massage may be introduced to control pain and swelling. As muscle function increases with exercise, venous and lymphatic drainage are enhanced, which causes further reduction of edema and pain. Pain can present a significant obstacle during the rehabilitation process. The judicious use of analgesics and anti-inflammatories is important during the first 2 weeks after injury. Effective pain management is patient specific. As the surgeon adjusts medications to achieve improved pain control, the therapist adjusts the splinting and exercise programs. Patients who remain pain focused more than 3 weeks into rehabilitation should be reevaluated by the referring surgeon to ensure continued bony alignment. Patients are referred for a pain clinic evaluation if signs of complex regional pain syndrome (CRPS) develop during treatment. If there is no evidence of CRPS or radiographic changes, therapy is often modified
General rehabilitation principles There are several principles of rehabilitation that are generally accepted as being beneficial regardless of the type of elbow injury. Edema and pain control and early initiation of active motion improve short and long term results. Later in the rehabilitation process, the use of superficial heat for the purpose of preconditioning tissues for
Fig. 1. Compression and icing is used for reduction of edema and pain.
OPTIMIZING ELBOW REHABILITATION AFTER INSTABILITY
in these patients to increase active mobilization. Patients remove protective splints while sedentary during the day to encourage increased motion, and should exercise more frequently at home. These patients should attend therapy more frequently for encouragement, edema/pain management, exercise reviews, and splinting modifications. Passive stretching for stiffness Regardless of the type of elbow injury, residual stiffness is a common problem during the latter stages of rehabilitation. Patients who present with elbow contractures should initiate passive stretching as long as the osseous and ligamentous structures are sufficiently healed, typically 6 to 8 weeks following the injury or surgery. Therapy sessions nearly always begin with some form of superficial heating for 15 to 20 minutes to precondition the tissues to make them more amenable to stretching. Patients either use hot packs while stretching with a weight or elastic band, or immerse the arm in a whirlpool and perform active motion (Fig. 2). Once the tissues are preconditioned, patients are positioned supine and the therapist performs passive ROM (Fig. 3). Modifications are made to the stretching program based on the patient’s injury, instability pattern, current ROM, healing, and pain threshold. Joint distractions are followed by physiologic passive stretching and then active motion. Strengthening exercises are performed at the end of the therapy session. The spectrum of instability Elbow instability is a general term used to describe a broad spectrum of injuries. It may refer
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to anything from an acute traumatic dislocation to a chronic laxity resulting in transient joint subluxation [6]. Instability may be present secondary to coronoid or radial head fractures, or damage to the varus/valgus ligamentous stabilizers of the elbow. O’Driscoll and colleagues [7] described a spectrum of instability, ranging from subtle posterolateral rotatory subluxation to full posterior dislocation. In stage 1, the elbow subluxates in a posterolateral direction. Stage 2 includes incomplete (or perched) dislocation of the ulnohumeral joint with the tip of the coronoid resting on the trochlea. Stage 3 is subdivided into stage 3A and 3B. In stage 3A, the ulnohumeral joint is completely dislocated, but the anterior band of the MCL is preserved. In stage 3B, all collateral ligaments are disrupted in association with complete ulnohumeral dislocation. Dislocations represent between 11% and 28% of all elbow injuries and the elbow is the second most common joint dislocated among the adult population. Managing stage 3 instabilities requires attention to both the MCL and the LCL. Dislocation of the elbow is termed either simple or complex based on the plain radiographs or computed tomography. Simple dislocations involve soft tissue structures only [8,9], whereas complex dislocations have associated fractures of the radial head, coronoid, or distal humerus [10]. Simple dislocations are generally managed by closed reduction. Recurrence of simple elbow dislocations is uncommon because of the intrinsic stability of the joint, but if they occur despite appropriate splinting and rehabilitation they require surgical ligament repair. Complex dislocations require restoration of the fractured articular structures by open reduction and internal fixation along with the repairs of one or both of the collateral ligaments.
Fig. 2. (A, B) The use of hot packs or whirlpool preconditions tissues before stretching in therapy to make passive and active stretching more effective.
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Fig. 3. (A, B) Passive physiologic stretching for elbow flexion and extension.
Lateral injuries Biomechanics The lateral ulnar collateral ligament is the primary stabilizer against posterolateral rotatory instability and varus instability [7,11]. Because the ligament attaches at the axis of rotation, it is uniformly taut during elbow motion [3,12]. Several studies have shown that division of the radial collateral ligament and lateral ulnar collateral ligament causes a significant increase in varus and posterolateral rotational instability [3,13–15]. Posterolateral rotatory instability (O’Driscoll type 1) is the most common pattern of acute and chronic elbow instability and often occurs as a result of fall on an outstretched hand [16]. There have also been studies demonstrating that the radial head and coronoid process act as secondary posterolateral rotatory stabilizers of the elbow [17,18] Furthermore, the anteromedial coronoid is an important secondary constraint to varus stability of the elbow. Hotchkiss [19] coined the term ‘‘terrible triad’’ as an injury consisting of fracture of radial head and coronoid process associated with a posterolateral dislocation of the elbow joint. Cadaveric studies have demonstrated the importance of the position of forearm rotation and active muscle contraction in stabilizing collateral ligament deficiencies of the elbow [20,21]. Cohen and Hastings [22] reported that forearm pronation spontaneously reduces posterolateral rotatory instability when the lateral ligamentous complex is disrupted. Investigations following sectioning of the LCL have concluded that the elbow was most stable under active flexion with the forearm in pronation and least stable with the elbow moved passively and with the forearm in supination [23– 25]. Dunning and colleagues [26] identified that
active flexion with the forearm in pronation created a more normal motion pathway than in supination. Varus moments, such as abduction of the shoulder, should be avoided in the LCL-deficient elbow. Following LCL repair, maintaining the forearm in pronation and performing active motion keeps the extensor/supinator group of muscles tensioned, which contributes to the stability on the lateral side. The extensor muscles originating from the lateral epicondyle prevent the forearm unit rotating away in posterolateral direction [14]. Optimizing rehabilitation for lateral injury Posterolateral rotatory dislocations are the most common form of elbow instability and occur as a result of a fall on an outstretched hand with the forearm in supination. The fall causes an axial load in the valgus direction and produces a sequential disruption of the stabilizing structures starting laterally and progressing medially [16]. Complete dislocations of the elbow without associated fractures always tear both the MCL and LCL; however, the extent of injury is typically more severe laterally and this often dictates the appropriate therapy. Most isolated elbow dislocations can be successfully managed nonoperatively following a closed reduction under sedation. Patients who have fracture-dislocations can be managed nonoperatively if the fracture fragments are small and do not interfere with motion. Larger displaced coronoid and radial head fractures are usually treated operatively with open reduction and internal fixation. For patients who have associated severe radial head fractures, prosthetic replacement is preferred to excision to minimize secondary complications of valgus and posterolateral rotatory instability [27–30]. If surgery is performed, the LCL is usually repaired; however,
OPTIMIZING ELBOW REHABILITATION AFTER INSTABILITY
the MCL frequently is not. The quality of the ligament repair achieved is variable depending on the extent of injury. Following either nonsurgical or surgical reduction of an elbow dislocation, joint stability and the stable arc of motion are assessed intraoperatively with an image intensifier. Postreduction lateral elbow radiographs are performed to check for residual joint subluxation in the initial splint. Patients who have repair of anteromedial coronoid fractures with or without LCL repairs also require careful rehabilitation to protect the LCL during healing. Sometimes the LCL is sectioned by the surgeon and subsequently repaired during the management of capitellum fractures, radial head fractures, when performing elbow contracture releases for stiffness, and following total elbow arthroplasty. Finally, patients who have chronic varus or posterolateral rotatory instability are usually managed with a reconstruction of the lateral ulnar collateral ligament, which also needs protection during rehabilitation to avoid stretching out or failure of the graft during healing. Discussion between the surgeon and therapist is essential to plan the optimal rehabilitation program, which should be tailored to the intraoperative findings and the evaluation of stability following joint reduction or ligament repair. The progression of therapy is based on the stability of the elbow and physiologic changes that occur with healing. The goal of therapy is to reduce pain and swelling, restore elbow and forearm motion, and maintain elbow stability. Early therapeutic intervention is critical to regaining elbow motion and function. Patient education is of vital importance to ensure that the patient understands the injury or surgery, the splinting and exercise routine, the importance of compliance with the therapeutic program, and the precautions that must be observed to prevent recurrent instability. It is preferred that the patients are seen in therapy between 1 and 3 days following reduction of the elbow. The progression of therapy can be divided into three phases. Phase I: day 1 to 4 weeks LCL deficiencies are best splinted with the forearm in pronation and the elbow at 90 degrees of flexion. This position can be achieved by using a posterior thermoplastic splint positioning the forearm in pronation and the wrist in slight extension (Fig. 4). Positioning the forearm and wrist in this position reduces the stress on the lateral soft tissue structures. Because the anterior joint
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Fig. 4. A resting splint in pronation for lateral-sided injury.
capsule is torn in patients who have dislocations, splinting at greater than 90 degrees of elbow flexion is likely to produce elbow flexion contractures. The splint is worn continuously for a period of 3 to 4 weeks except for exercise periods and skin care. Patients are cautioned about the gravitational force on the lateral structures of the elbow joint while performing overhead exercises [6], while sleeping, or by laying the arm across the chest. Internal rotation of the shoulder results in a varus force being applied across the elbow, loading the deficient LCL and possibly causing lateral joint gapping. External rotation of the shoulder applies a rotational torque across the elbow, which can result in the radial head subluxing posterolaterally. A nighttime posterior elbow extension splint with the forearm maintained in pronation may be introduced at 3 weeks if patients stiffen quickly and are having difficulty extending the elbow. The splint is progressively adjusted as the patient gains elbow extension. Exercise program Exercises are commenced within 1 week following the reduction of the elbow. The program starts with active assisted or overhead exercises initially, progressing to active and then resisted exercises based on the healing stages and the stability of the elbow joint. Several studies have identified the adverse effects of immobilization following simple or complex elbow dislocations. Flexion contractures, pain, and loss of function are common complications of immobilization [31–35]. Early mobilization of the elbow joint following reduction produces a functional arc of motion in most patients [36].
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Early mobilization depends on the following factors: joint stability following reduction, whether an extension block is needed for stable arc of motion, and the presence of a drop sign [37]. If the elbow joint is stable after reduction, active elbow ROM exercises with the forearm in pronation are performed 10 to 15 times every 2 to 3 hours. Forearm rotation exercises are only performed with the elbow in 90 degrees or greater flexion. In the presence of a drop or sag sign, (a radiographic gap between the ulna and humerus) it is important that isometric exercises of triceps and brachialis are performed while in the splint at regular intervals to reduce ulnohumeral separation (Fig. 5) [38]. In addition to the isometric exercises, overhead exercises consisting of elbow flexion and extension (with forearm pronated) and forearm rotation with the elbow at 90 degrees of flexion are effective in reducing gravitational force while allowing stable arc of motion (Fig. 6) [6]. The overhead exercises are performed in supine with the shoulder flexed to 90 degrees and neutral rotation. The effect of gravity and activation of the triceps provides stability to the elbow joint as the motion is performed [6]. If the surgeon believes that the elbow is unstable, active extension of the elbow is initially limited to prevent recurrent dislocation and increased 10 to 15 degrees per week as healing progresses. The entire exercise program is customized to the patient’s specific pathoanatomy and residual instability depending on the various factors described earlier. Passive stretching should be avoided in the early phases of healing because of the theoretic risk for causing heterotopic ossification and the potential for inducing instability.
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Shoulder, wrist, and digital active motion exercises are performed throughout the rehabilitation program. Once pain and swelling are under control, resisted wrist and digital extensor exercises are added to the previous program if the muscle origins are known to be intact. Strengthening of the extensor muscles originating from the lateral epicondyle further increases the stability of the elbow joint [22]. Phase II: 4 to 6 weeks Joint stability is often achieved by 4 to 6 weeks following trauma or surgery. The goal of this stage of elbow rehabilitation is to maximize elbow and forearm range of motion while maintaining elbow stability and maximizing the strength of the lateral muscles. On confirmation of joint stability from the referring surgeon, the posterior elbow flexion splint is discontinued. A collar and cuff are worn while out of the house and while active. Edema is often not a concern at this stage. Heat is applied before exercise to increase the compliance of the tissues and allow a greater arc of motion. Flexion–extension exercises are performed with the forearm in neutral position 20 to 25 times on an hourly basis. Forearm rotation exercises are still performed, however, with the elbow in 90 degrees of flexion. Wrist and digital extensor strengthening with greater resistance is continued along with grip strengthening exercises. At this stage patients are encouraged to perform light ADL as long as the combined motion of elbow extension and forearm supination is avoided. A well-written home program and review of precautions enhances patient compliance. Flexion contractures are a common complication following elbow trauma. A nighttime elbow extension splint molded to the anterior aspect of the elbow is helpful to gain extension (Fig. 7). This splint is adjusted as the extension gains are made. Phase III: 6 to 12 weeks
Fig. 5. The drop sign showing a radiographic gap between the humerus and ulna.
Concerns regarding joint stability in this phase are minimal. The precautions of limiting motion of the elbow and forearm are lifted in consultation with the referring surgeon. The goal of therapy in this phase is to increase mobility, strength, endurance, and overall upper extremity function. Once the ligamentous and osseous healing is secure progressive elbow strengthening using weights and elastic bands is incorporated into the program. Strengthening of elbow flexors with the forearm in pronation are performed for the
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Fig. 6. (A, B) Overhead flexion and extension in supine position. The contralateral arm is used for support.
first 2 weeks. This method of strengthening minimizes an excessive load on the lateral structures of the elbow, thus reducing the chance of recurrent elbow instability. Elbow flexor strengthening with the forearm in supination is initiated later. Triceps strengthening must also be incorporated during the strengthening program. Shoulder, forearm, wrist, and hand strengthening are of critical importance at this phase of elbow rehabilitation. Contracture formation causing elbow joint stiffness is a common complication following elbow dislocations. Application of heat and stretch, passive range of motion, joint
Fig. 7. The nighttime elbow extension splint.
mobilization, and static progressive splinting have added benefits in restoring elbow motion.
Medial injuries Biomechanics The anterior bundle of the MCL is considered to be the primary constraint to valgus instability throughout the arc of elbow motion [5,20,39,40]. The posterior bundle of the MCL provides additional stability to the ulnohumeral joint but only during flexion because it attaches to the medial epicondyle even more posterior to the flexion axis of the elbow. The secondary stabilizer for valgus loading is the radial head. Radial head excision with MCL deficiency has been shown to markedly reduce valgus stability [11,41]. The radial head provides a mechanical buttress against excess valgus as it engages the capitellum under valgus loading. Other valgus stabilizers include the anterior joint capsule and the muscles crossing the elbow. The anterior joint capsule provides a small amount of stability when the elbow is in full extension; however, the capsule is typically disrupted in patients who have elbow dislocations [11]. The anterior joint capsule becomes
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redundant when the elbow is flexed and provides no contribution to the stability of the elbow joint in this position [11]. The muscles crossing the elbow contribute to dynamic stability of the joint. Park and Ahmad [42] studied the contribution of the flexor-pronator mass to valgus stability of the elbow in cadaveric models. They found the primary dynamic constraints to be the flexor carpi ulnaris and flexor digitorum superficialis muscles. This finding has implications for rehabilitation. Early strengthening of these muscle groups following MCL injury is not only safe to perform but may also ultimately help to contribute to dynamic valgus stability of the elbow. The position of the forearm also has an effect on elbow stability after medial-sided injuries. Safran and colleagues [20] recently studied the effect of forearm rotation of valgus laxity of the elbow. They concluded that valgus laxity was greatest with the forearm in neutral forearm rotation, and greater stability was achieved with either full pronation or full supination. Other research has shown forearm supination to be the most stable for resisting valgus load [39,43]. Armstrong and colleagues [39] performed an in vitro biomechanical study of the MCL-deficient elbow in 2000 and demonstrated that active motion and forearm supination stabilized the MCL-deficient elbow. They hypothesized that forearm supination creates an external moment on the ulna that allows the medial side of the elbow to close, effectively stabilizing the MCL-deficient elbow. Another hypothesis for the increased stability on the medial side offered by forearm supination is the mechanics of the distal radioulnar joint [40]. When pronated, a lateral translatory motion of the ulna at the distal radioulnar joint occurs. The ulna translates medially in supination. This translatory motion of the ulna can effectively open the ulnohumeral joint when the integrity of the collateral ligaments is compromised. Supination also increases tension on the flexor/pronator group, which has been shown to contribute to dynamic stability for valgus loading [42]. Optimizing rehabilitation for medial injury MCL injury can occur following an acute traumatic event or develop as a chronic condition in throwing athletes or individuals who place repeated valgus loads on the elbow. MCL disruption can occur in isolation following a fall or combined with an elbow dislocation or fracture of the radial head. Repair of the MCL in patients
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who have terrible triad injuries of the elbow is frequently not performed if a stable repair of the coronoid, radial head, and LCL is achieved. In patients who have a secure LCL repair, rehabilitation protocols should be developed in conjunction with the therapist to protect the unrepaired MCL to ensure optimal healing. Reconstruction of the MCL is often necessary in chronic situations to facilitate competitive throwing athletes to return to activity and requires specialized rehabilitation protocols to allow them to return to highlevel sports. Regardless of whether the MCL is repaired following an acute traumatic event or reconstructed for a chronic athletic injury, rehabilitation must be geared toward maximizing motion and muscular strength without compromising stability. Phase I: day 1 to 4 weeks Patients are typically referred to therapy within 1 week following injury or surgery. The referral must indicate the safe arc of motion as assessed intraoperatively along with any associated fractures or soft tissue injuries. Patients are splinted with the elbow at 90 degrees and holding the forearm in maximum supination. Because the MCL lies close to the axis of elbow motion, holding the elbow at 90 degrees does not place excessive stress on the anterior portion of the MCL during healing. Placement of the elbow at 90 degrees does place slight stress on the posterior band of the MCL. This stress is beneficial because the posterior band tends to scar down and shorten following trauma and immobilization and may prevent achieving end-range flexion. Patients are educated about the injury and precautions on the first day of therapy. Aggressive edema control is instituted immediately as discussed previously. Patients remove the splint and perform exercises every 2 hours, and are instructed to use ice after every other exercise session. Superficial cold combined with compression using a cryo-cuff or other device is also effective for edema control. Exercise sessions are performed with the arm in vertical orientation with the patient in a seated position. We use this position because it has been shown to be safe when treating elbows with valgus instability. Patients perform active flexion and extension in maximum supination. Forearm rotation is performed with the elbow flexed past 90 degrees. Active motion is performed to create a joint reaction force from muscular contraction,
OPTIMIZING ELBOW REHABILITATION AFTER INSTABILITY
which effectively maintains the elbow in alignment during exercises. Isometric contraction of the elbow flexors and extensors are performed every hour while in the splint to facilitate elbow joint congruity and maintain muscular strength during this period of disuse. Phase II: 3 to 6 weeks Regaining terminal extension can occasionally be difficult, as is the case with most rehabilitation programs following elbow trauma. Our expectations for extension in most situations are that the patient can extend to 40 degrees in the first postoperative week and make weekly gains of 10 degrees per week unless severe instability is present. If the elbow is deemed to be stable in consultation with the treating surgeon and the patient fails to reach these goals, nighttime extension splinting in supination is added to the program at 3 to 6 weeks. The extension splint is monitored weekly and adjusted if necessary to accommodate increases in extension. The resting splint is removed and gentle resistance is added for gripping and for resisted ulnar deviation/flexion of the wrist while holding the elbow in flexion during therapy sessions. Early initiation of strengthening of the flexor/pronator group in this fashion may help contribute to longterm stability against valgus stress at the elbow. The remainder of this phase from a therapy perspective involves facilitation of ongoing reduction in edema, reinforcement of the home exercise program and precautions, initiation of the use of heat before exercise to increase tissue elasticity, and scar management.
35
flexion turnbuckle must be used because it transfers a precise rotational component to the joint and avoids painful compression (Fig. 8) [44]. These splints should provide a low-load, prolonged stretch to the elbow. We recommend at least three sessions of splinting per day, with each session lasting between 30 minutes to 1 hour. Any symptoms of ulnar neuropathy during splint use are a relative contraindication to its use. Patients are educated in this regard during splint fabrication. In-line progressive resistive exercise for elbow flexion and extension with the forearm in supination is initiated at week 8. Valgus loading of any kind is avoided until week 12. Considerations for throwing athletes The medial side of the elbow is susceptible to injury in athletes because of the repetitive valgus force placed on the elbow while throwing. The rehabilitation goals for athletes are similar to the rest of the population: decrease edema, restore full motion, maintain stability, and regain muscular strength. The high demands placed on the elbow after injury or surgery in repetitive valgus loading must be taken into account at the time of the operation and during the rehabilitation process. Flexion contractures are a common complication following any elbow injury or operation. A small flexion contracture of 10 to 20 degrees often presents no functional limitation for most patients. Any amount of elbow flexion contracture can present significant disability for high-level
Phase III: 6 to 12 weeks Protective splinting is discontinued and patients begin using their injured upper extremity at week six as long as any associated fractures show radiographic evidence of early union. Passive range of motion for flexion and extension is initiated if residual limitations in range of motion persist. The posterior band of the MCL can adaptively shorten and scar after trauma, limiting flexion. In cases in which regaining terminal flexion is not accomplished through active and passive stretching, a static progressive flexion cuff or turnbuckle splint can be used to supplement the patient’s home exercise program. The flexion cuff may be used for patients who have greater than 110 degrees of elbow flexion. For patients who have very stiff elbows, the static progressive
Fig. 8. Static progressive splints for elbow flexion. The turnbuckle splint with the hinge must be used for patients who have very stiff elbows to minimize compression forces on the elbow joint.
36
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athletes, however. We prefer the use of a hinged brace in supination for these patients. The brace is initially set to allow motion from 40 to 110 degrees postoperatively (Fig. 9). The brace is adjusted weekly to allow a 15-degree increase in ROM in both directions. Patients remove the splint to perform active wrist, digit, and shoulder ROM. Active forearm rotation is performed with the elbow held in maximum flexion. The other main difference between throwing athletes and the remainder of the population is the progression of strengthening. Isometric in-line strengthening is initiated at week 4. Active resisted exercise is initiated at week 8, but remains in-line (no valgus loading) until week 12 to 14. Patients then begin a formal throwing program, as outlined by Wilk and colleagues [45], in week 16. This program consists of progressive long toss, followed by flat ground throwing, and finally pitching off a mound. Serial increases in effort begin once the long toss portion of the program is complete. Patients must be closely monitored by team staff and trainers to ensure that patients are pain free to prevent overexertion by overzealous athletes who are eager to return to sports. Typically pitchers do not return to high-level throwing for 1 year following an MCL reconstruction, and may improve velocity and ball control for up to 2 years. Optimizing rehabilitation for type 3 elbow dislocations The primary goal of therapy following reduction of elbow dislocation is to serially increase ROM while maintaining the reduction and preventing undue stress on the collateral ligaments.
Fig. 9. The hinged, locking elbow brace holding the forearm in supination.
et al
All patients are initially splinted in a posterior elbow splint holding the joint in 90 degrees of flexion for 5 to 7 days. They then begin protected active motion. If the elbow is stable once reduced, then unrestricted active motion is permitted. If instability is an issue, then full flexion is permitted but extension of the elbow past 60 degrees is avoided. Patients perform elbow flexion and extension exercises while supine in the overhead position as previously discussed for lateral injuries. Extension is increased by approximately 15 degrees per week. The position of the forearm in supination, pronation, or in neutral while performing extension depends on which ligaments are damaged. Neutral position of the forearm is used when both sides of the elbow remain unstable. Nighttime extension splinting is added to the program if patients fail to achieve weekly goals for extension. Passive stretching of the elbow should not be performed until after week six to ensure that the ligamentous stability is no longer an issue and that no heterotopic bone has formed. Aggressive stretching before week six may lead to greater stiffness, pain, instability, and loss of functional use. Protective splinting is discontinued at week six except for heavier activities of daily living. Passive range of motion is initiated at this point to address any motion limitations. Light progressive strengthening exercises are initiated at week eight and progressed as tolerated.
Summary Recent biomechanical studies have shown that following MCL transection active mobilization of the elbow in supination is beneficial, whereas passive mobilization and pronation tend to cause greater instability. Similarly, for patients who have LCL insufficiency, varus loads need to be avoided and pronation of the forearm has been demonstrated to be helpful in maintaining stability. These latter two facts are critical elements to developing a rehabilitation program for patients who have both acute and chronic instability of the elbow. Optimizing elbow rehabilitation after instability presents numerous challenges. The primary challenge is to find the balance between early motion for prevention of stiffness and maintaining stability. Contractures of the elbow joint develop if the elbow is immobilized. Early mobilization and splinting of the elbow following injury predictably leads to superior results as long
OPTIMIZING ELBOW REHABILITATION AFTER INSTABILITY
as there is close communication between the surgeon and therapist outlining the pathoanatomy and safe arc of elbow motion assessed intraoperatively.
[18]
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