Treatment of Simple Elbow Dislocations



Fig. 4.1
Supine technique for reducing a posteriorly dislocated elbow



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Fig. 4.2
Prone technique for reducing a posteriorly dislocated elbow


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Fig. 4.3
Alternative supine technique for reducing a posteriorly dislocated elbow


In all reduction techniques, firm, continuous traction should be applied to overcome the muscle spasms around the elbow that occur after injury. Once these muscles fatigue, the elbow may be more easily reduced. Some surgeons prefer to recreate the deformity by applying a supination, extension, and valgus force with axial traction [22]. This allows the coronoid to clear the distal humerus, and then the olecranon can be manipulated distally. Forearm supination during reduction is important to clear the coronoid under the trochlea, minimizing additional trauma to the intact medial structures [19]. A perched dislocation is reduced by gentle axial distraction and direct pressure over the olecranon while the elbow is slightly extended [23]. A thorough neurovascular examination should always be performed after a reduction attempt.

It is necessary to assess joint stability after reduction. This is performed by moving the elbow through a full range of motion in flexion and extension in neutral rotation. The examiner should note the position where any recurrent subluxation or dislocation occurs. Stability can be confirmed using fluoroscopy during flexion and extension. Valgus stress should be tested with the forearm fully pronated because otherwise posterolateral instability may be mistaken for valgus instability [7]. Full pronation enables the intact medial structures to prevent posterolateral rotatory instability (PLRI) . If valgus stability is demonstrated in pronation, the aMCL can be assumed to be intact [19].

Full pronation renders the elbow more stable in an isolated LCL injury by tensioning any intact medial ligaments or any intact lateral musculotendinous (common extensor) origins [19, 24]. On the other hand, in isolated MCL damage, the elbow is usually more stable in supination in which any intact lateral ligaments or medial musculotendinous (flexor-pronator) origins are tightened. Elbow stability is not affected by forearm rotation if both the LCL and the MCL are disrupted [9].

If the elbow is stable throughout an entire arc of motion, a splint is applied in 90° of elbow flexion with whatever forearm rotation achieves the greatest stability [9]. Anteroposterior and lateral radiographs are performed after reduction and splinting. The patient should be seen in the clinic within 7 days to obtain follow-up radiographs. The literature shows a range of recommendations for immobilization. The duration of immobilization in a resting splint should not exceed 2 weeks. It has been shown that immobilization in a splint for 2 weeks enhances comfort and does not have a significantly adverse effect on the final functional outcome [25], whereas longer periods of immobilization can increase elbow stiffness [1]. Because the risk of posttraumatic stiffness after an elbow dislocation is much higher than that of instability in simple elbow dislocations , some surgeons apply a splint for only 1 week [9, 12, 23]. Others just apply a sling for comfort to allow for early active range of motion as soon as pain allows [11]. The argument supporting this protocol is that better final functional outcomes may be seen with the application of a sling and early active mobilization. Maripuri et al. compared the results of a 2-week immobilization followed by physiotherapy versus the application of a sling followed by early active mobilization [26]. They found that early active mobilization provided better functional outcomes, required a shorter duration of physiotherapy, and allowed an earlier return to work. The sling and early active mobilization protocol did not result in any late elbow instability or early recurrent dislocations. Finally, an alternative to the sling is a hinged brace allowing range of motion for therapy while providing varus/valgus stability [17]. Also, a hinged brace is useful when a particular forearm rotation is required to maintain a stable arc of motion or when an extension block is needed to maintain stability [9, 17].

The patient should be seen in clinic within 7 days after injury to recheck a concentric reduction on radiographs and to initiate active range of motion. Follow-up visits are every 5–7 days for a total of 3 weeks after injury [7]. It is important to check for a drop sign on follow-up radiographs. The drop sign is an objective, static, radiographically measurable increase in the ulnohumeral distance noted on the lateral elbow radiograph (Fig. 4.4). A persistent drop sign on both the immediate post-reduction radiographs and subsequent follow-up radiographs should not be overlooked because it may denote the presence of rotational instability. If left untreated, rotational instability may lead to chronic pain with heavy work and sports activities [27]. If the drop sign is persistent, then stress testing should be performed. If stress testing reveals persistent instability, further protection by a hinged brace or repair should be considered [2] (Fig. 4.5). MRI is indicated in the rare cases of an unexplained nonconcentric reduction. MRI may reveal incarcerated cartilage fragments or soft tissue [10].

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Fig. 4.4
Lateral X-ray with drop sign


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Fig. 4.5
Lateral X-ray with resolved drop sign

Range of motion is initiated as soon as possible and is preferably active and not passive. Active muscle contraction acts as a stabilizing compressive force across the joint, whereas passive motion may cause distraction and subluxation [17]. Early active mobilization increases the final range of motion, decreases contractures, and improves patient satisfaction and functional outcomes [18].

If subluxation or dislocation in extension is present after reduction, or if subluxation is seen on post-reduction radiographs , then joint stability must be reassessed in full pronation. If forearm pronation eliminates the instability in extension, a hinged brace is applied that allows unlimited flexion and extension while holding the forearm in full pronation. If there is residual instability in full extension or near full extension, an extension block is added [7]. The extension block is adjusted such that it progressively allows more extension. It should be completely removed before 6 weeks after injury and should allow for full range of motion before removal [9]. The elbow should be reassessed similarly in each follow-up visit.

Indications for surgical treatment include residual instability in more than 45° of flexion, joint incongruence on post-reduction radiographs, and/or an open dislocation [17]. Two surgical approaches have been described to address elbow dislocation : the posterior midline incision and the dual-incision approach. A posterior midline skin incision , with full-thickness lateral and medial fasciocutaneous flaps, allows access to both sides of the elbow using a single incision with minimal disruption of local cutaneous nerves [28]. It also avoids different skin incisions in case other elbow procedures are performed later. A dual-incision approach involves a lateral skin incision to address the lateral collateral ligament disruption, with or without a medial incision to address the medial collateral ligament. It provides excellent visualization and avoids the complications of large soft tissue flaps [17] such as hematoma and skin necrosis. The lateral collateral ligament is addressed before operating on the medial side, and stability is reassessed. The medial collateral ligament should be repaired only if there is gross instability after lateral collateral ligament repair [3, 17, 23].

In order to repair the lateral collateral ligament complex, the interval between the extensor carpi ulnaris and anconeus can be utilized. The common extensor origin and lateral capsuloligamentous structures are usually already avulsed from their attachments on the humerus [17, 29, 30], leaving the lateral epicondyle exposed. The LCL , along with the capsule and common extensors, are reattached to the lateral epicondyle using bone tunnels or suture anchors with the elbow in 30° of flexion [17]. Overtensioning of these structures should be avoided [31]. The lateral collateral ligament should be attached to the lateral epicondyle at a point that renders the ligament isometric. The radial collateral ligament is essentially isometric. The lateral ulnar collateral ligament is loose in extension and tightens with elbow flexion. A point 2 mm proximal to the center of the capitellum has been calculated to be the most isometric point of the lateral ulnar collateral ligament and should be the location of the repair [32]. If the lateral collateral ligament tear is intra-substance, it is repaired directly with high-strength, nonabsorbable sutures [4]. The radiocapitellar and ulnohumeral joints should be inspected for soft tissue (annular ligament or capsule) or bony/cartilaginous fragment interposition that may have prevented a complete reduction resulting in persistent instability. More commonly, a persistently unstable simple dislocation is a result of a complete lateral collateral ligament complex avulsion with the extensor tendons and an avulsion of the entire medial collateral ligament complex with the flexor-pronator mass. Isolated lateral collateral ligament and extensor tendon repair is typically enough to restore stability in these severe injuries and medial repair is not typically required.

If instability persists after the lateral repair, the medial collateral ligament and flexor pronator can be repaired. During the approach to the medial collateral ligament, the ulnar nerve must be identified and protected. Transposition of the ulnar nerve is controversial and is not routinely performed by the senior author. The flexor/pronator muscle mass is usually injured in cases where the medial side needs a repair. The medial collateral ligament and flexor/pronator mass are repaired to the medial epicondyle in a similar manner to the lateral structures, with the elbow in 30° of flexion by placing two suture anchors, one anterior and one posterior, to the isometric point to repair the medial collateral ligament and the flexor/pronator mass to the medial epicondyle. Alternatively, the medial collateral ligament can be repaired with a heavy nonabsorbable high-strength suture in a running locked Krackow fashion through a bone tunnel in the medial epicondyle at the isometric point similar to a docking technique. The flexor /pronator mass would still be repaired with anchors as previously described.

If instability persists after medial and lateral collateral ligament repairs, a static or dynamic external fixator should be placed to restore stability. The requirement for an external fixator in cases of persistent elbow instability in cases without fracture is exceptionally rare. Consequently, surgeons should be alerted to potential missed osseous or cartilaginous injuries in cases where medial and lateral collateral ligament repairs are insufficient to restore stability. Rare cases requiring a fixator may be in cases of delayed reductions where the ligaments are compromised and an adequate repair cannot be performed. In these cases, reconstruction should be considered an alternative to external fixation as reconstruction would restore tissue and potentially prevent late instability after the fixator has been removed.

Postoperatively, after a reduction and collateral ligament repair, the elbow is kept in a resting posterior splint in 30° of flexion for 7–10 days [17, 33]. Active assisted range of motion could start at this time. A hinged brace with an extension block (approximately 30°) is used for 6 weeks postoperatively. The extension block is gradually decreased until full extension is allowed by 3 weeks postoperatively. The brace is removed and daily activities are allowed without it at 6 weeks postoperatively . Strengthening is usually initiated 10–12 weeks postoperatively. The patient may participate in sports while in the brace at this time and will continue brace wear with sports activities for a total of 3–6 months postoperatively (Fig. 4.6) [3, 17].

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Fig. 4.6
Treatment algorithm for simple dislocations



Published Outcomes and Complications


The prognosis of a simple elbow dislocation is generally good [25]. Simple elbow dislocations that are stable after initial reduction are usually managed with nonoperative treatment and early active mobilization. This provides a high level of patient satisfaction and good functional outcomes [34]. Nonoperative treatment , however, does not lack minor drawbacks. Most patients treated nonoperatively have minor complaints and do not consider themselves fully recovered [11, 27]. More than half of the patients treated nonoperatively complain of residual stiffness and pain in long-term follow-up, especially during heavy work and sports participation [27, 34]. The decrease in the mean flexion arc in the dislocated elbow ranged from 5° to 11° compared to the normal elbow [27, 34, 35]. Josefsson et al. [30], however, showed that surgical management of these elbows is not superior to nonoperative treatment . Although they found that both collateral ligaments were torn in all the studied patients, they still did not recommend early surgical treatment of simple elbow dislocations that can be reduced by closed methods. For a grossly unstable or irreducible elbow dislocation, surgery is the treatment method of choice. Surgical repair of the lateral and/or medial soft tissue stabilizers provides satisfactory outcomes [36]. Primary ligament repair for unstable elbows is superior to nonoperative treatment because it allows early motion, achieves joint stability, and avoids a complicated later ligament reconstruction [33].

Joint contracture is the most common complication of elbow dislocation [17]. Longer periods of immobilization increase the risk and magnitude of a flexion contracture [9, 11, 37, 38]. However, a contracture may be prevented with early active mobilization [11, 37, 38]. Progressive static splinting is started 4–8 weeks after injury if contracture occurs and the range of active motion is less than 30–130° [39]. If no remarkable improvement is achieved (there is less than 10° change over 3 months), then a turnbuckle orthosis can be used [38, 40]. Surgery is indicated if no remarkable improvement occurs despite using a turnbuckle orthosis for 3 months. The choice of surgical procedure depends on the main cause of the decreased range of motion. Many surgical procedures have been described including anterior and posterior capsulectomies, excision of heterotopic ossification, removal of osteophytes, and interpositional or total elbow arthroplasties [41, 42]. The most commonly performed procedure in the case of a stiff elbow after a simple dislocation is a release, either open or arthroscopic, with a capsulotomy or capsulectomy of the both the anterior and posterior compartments. Limitation of rotation is uncommon in these injuries; consequently, only the anterior and posterior capsule typically needs to be addressed. If heterotopic ossification is involved, then removal is required as well typically in an open fashion.

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Aug 14, 2017 | Posted by in MUSCULOSKELETAL MEDICINE | Comments Off on Treatment of Simple Elbow Dislocations

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