Surgical Anatomy.

The radial head is an eccentric dish-shaped structure with a variable offset from the neck and angled 15 degrees oriented away from the radial tuberosity, with implications for fracture fixation or prosthetic replacement. Likewise, the proximal radioulnar articulation needs to be considered in reconstructive or replacement procedures. The cartilage of the radial head represents an arc of about 280 degrees about the rim of the radius. Hardware placement should avoid the articulating region, which can be visually identified as a thickened area of cartilage. In addition, the safe zone for hardware placement has been defined as within a 90-degree arc bounded by the Lister tubercle and the radial styloid distally or simply the lateral aspect of the radial head when the forearm is in neutral.

The two most commonly used approaches to the radial head include the Kocher interval between the extensor carpi ulnaris (ECU) and anconeus and the common extensor splitting approach. The Kocher interval is far away from the region of the posterior interosseous nerve, but the lateral ulnar collateral ligament is at risk with this approach. The lateral collateral ligament complex includes a coalescence of several structures, including the most important stabilizing structure, the lateral ulnar collateral ligament (LUCL), the annular ligament, and the accessory lateral collateral ligament. The LUCL arises from the anterior inferior lateral epicondyle and inserts upon the crista supinatoris of the ulna. If the Kocher approach is used, during dissection, the surgeon attempts to preserve the ligament and enter the joint anterior to it.

An alternative exposure is to split the origin of the extensor digitorum communis at the lateral epicondyle ( Fig. 46A-4 ). This approach preserves the LUCL, but at the distal aspect of the surgical dissection the posterior interosseous nerve (PIN) may be encountered. The PIN arises as the continuation of the deep radial nerve near the radiocapitellar joint. It then passes about the lateral aspect of the radius and through the supinator, which it innervates. To help protect the PIN during this approach, the forearm may be pronated, which results in the PIN falling more distally away from the surgical field of dissection. The surgeon should keep in mind that the PIN typically may be found between 2 and 5 cm distal to the radiocapitellar joint, depending on the size of the patient and position of forearm rotation.

An approach to the radial head splitting the extensor digitorum communis (EDC) origin allows good access for fixation of fractures or radial head replacement and obviates risk of injury to the lateral ulnar collateral ligament (LUCL).

Positioning Techniques.

In general, the authors prefer supine positioning for the approach to the radial head. We also prefer general anesthesia, as positioning may be uncomfortable in the awake patient and the nerves may be immediately assessed in the postoperative period with general anesthesia as opposed to regional. The patient is placed supine and the arm prepped from fingertips to axilla. An arm table may be used or the arm may be placed across the patient’s chest. Alternatively, an arm board is very helpful to use so that the advantages of both positions may be exploited. The arm board may be rotated inward during part of the case or left at a right angle to facilitate exposure. It is also extraordinarily easy to rotate the arm board out of the field and allow for easy use of the mini fluoroscopy unit.

A sterile tourniquet is applied and later inflated to 200 mm Hg to provide hemostasis during the case. A mini fluoroscopy unit is used to image during the case.

Surgical Approach.

The authors prefer a lateral-based incision for exposure of isolated radial head or lateral-sided injuries. If it is thought that medial and lateral structures need to be addressed, an alternative is a single posterior incision; however, our preference is to make separate lateral- and medial-based incisions to limit the potential soft tissue dissection and potential for seroma formation under large skin flaps.

A gently curved incision is made centered over the lateral epicondyle and radial head. Subcutaneous nerves are identified and preserved and the muscular and tendinous origins of the extensor apparatus are exposed.

If the radial head fracture is accompanied by a concomitant LUCL injury, the approach exploits the ligament injury to perform the arthrotomy. With gentle probing, if it is not already readily apparent, the tissue defect over the lateral epicondyle and path of the LUCL avulsion can be identified. This represents the Kocher approach between the ECU and anconeus ( Fig. 46A-5 ). It is unlikely to injure the PIN with this approach as it is distant from the surgical dissection site, but if the collateral ligament is intact, it may be at risk of iatrogenic injury. Thus, this approach is not preferred unless the collateral ligament has avulsed.

The Kocher approach exploits the interval between the anconeus and the extensor carpi ulnaris (ECU). Care is taken to avoid injury to the lateral ulnar collateral ligament (LUCL). This approach is particularly useful when the LUCL is avulsed off, such as with terrible triad injuries and the radial head is to be fixed or replaced and the LUCL repaired.

(Source: © 2004, Mayo.)

When the collateral ligament is intact but a radial head fracture needs to be addressed, we prefer an approach that splits the extensor digitorum communis (EDC) origin in line with its fibers. The forearm is kept in pronation, which rotates the PIN further away from the operative dissection field. The radial head is exposed by this capsulotomy and the fracture is identified.

Reduction and Fixation Techniques.

After exposure, the fracture is then assessed and it is determined if it is amenable to fixation or best served by radial head excision or arthroplasty. Although it may be technically possible to fix some fractures, fixation may be tenuous, and some fractures may be more appropriately treated with arthroplasty. A few recent series suggest that type III and some type II fractures that undergo fixation do poorly in the setting of fracture-dislocations, comminution, or in conjunction with three or more fracture fragments.

Provisional fixation may be obtained with small Kirschner wires (K-wires) and towel clips or small pointed bone reduction clamps. Ideally, small screws or plates are placed for definitive fixation. Screw fixation is preferred due to lower profile and improved motion postoperatively; in addition, there is a high rate of hardware removal with use of plates. Occasionally bone grafting may be helpful.

If the radial head is to be replaced, care should be taken to avoid placing too large an implant. The native radial head or its fragments are assembled on the back table and help to define the proper size of implant to place. It should be remembered that the eccentric inner dish shape of the native radial head is the guide for the appropriate size for the implant, thus choosing a smaller implant than the entire radial head. The lesser sigmoid notch may be used as a guide, but is less reliable than the native radial head. In general, the radial head should sit within 2 mm of the proximal radioulnar joint.

Most implant systems have modularity, allowing one to choose appropriate head, neck, and stem sizing to recreate a semblance of normal anatomy. Available radial head implants include fixated devices secured into the radial neck and shaft with cement or by a press-fit mechanism; alternatively they can be intentionally loose, smooth-stemmed implants that are intended to act as a smooth spacer. Bipolar implants that insert firmly into the radial shaft by a fixed mechanism are available, with an articulating head-neck junction to allow motion. The major head choices are anatomic (with a fixated stem) or nonanatomic (with a smooth mobile stem). To date, little information is available regarding measurable advantages of one implant over another. However, when anatomic designs are used, it is important to place these prostheses in an anatomically accurate position.

Pitfalls and Avoidance of Complications

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    Radial head excision: Pitfalls in the setting of radial head surgery include excision of a radial head in the setting of unrecognized Essex-Lopresti injury or ligament injury. The radial head is an important stabilizer to the elbow in the setting of ligament instability or longitudinal instability of the forearm and either repair or replacement is required in such settings. Intraoperatively, the “radial pull test” may be used to assess the competence of the forearm stabilizers (the interosseous membrane [IOM], and the triangular fibrocartilage complex [TFCC]). After the radial head is resected, 20 lb of longitudinal traction is applied at the radial neck while the wrist is examined with fluoroscopy. If migration of the radius occurs as evidenced by ulnar positive variance and a change in this variance of more than 3 mm, then the IOM is likely torn. If more than 6 mm is seen, then both the IOM as well as the TFCC are likely torn and all of the forearm longitudinal stabilizers are gone. In this setting, radial head replacement as well as stabilization of the distal radial ulnar joint and the forearm are recommended.

    
    
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    Radial head replacement: One common complication associated with prosthetic complication is “overstuffing of the radial head” with too large an implant. This can lead to overloading of the joint space and maltracking of the joint with accelerated articular wear of the joint and pain. This is particularly problematic in the setting of concomitant ligament injury. If the fragments of the native radial head are available, it is easiest to attempt to match the size of the native head, realizing that the metallic radial head should match the inner diameter of the dish of the radial head. Other complications can be related to implant choice. Care should be taken when anatomic radial head designs are placed, as nonanatomic placement of an intentionally anatomic, fixed design can lead to abnormal tracking and wear on the capitellum. In addition, in the setting of longitudinal instability of the forearm, bipolar type implants should be avoided, as the articulating joint at the neck may allow escape of the implant with axial loading.

    
    
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    Radial head ORIF: Pitfalls and complications in radial head fixation include an attempt to fix a radial head that might be better served by replacement arthroplasty, hardware prominence that may restrict motion (particularly common in the setting of plate fixation of fractures), and hardware issues associated with impingement at the proximal radioulnar joint or into the radiocapitellar joint. Attention to avoiding the articular surfaces as described in the fracture fixation section can help reduce this risk. Likewise, patients should be counseled preoperatively about the potential need for hardware removal particularly in the setting of radial head and neck fractures fixated with plates.

  
  

Management of Intraoperative Problems.

Intraoperative problems include difficulty fixing a fracture and need for conversion to radial head implant. It is therefore a good idea to have implants available for all anticipated possibilities. In general, we suggest having available a variety of small screws and plate and screw devices, a radial head implant, and being prepared to repair the collateral ligaments via bony tunnels or suture anchors. In addition, in the setting of gross instability, the surgeon should be prepared to proceed in a stepwise fashion to repair injured structures so that the patient will leave the operating room with a stable elbow. Typically, in the setting of instability, we address radial head fractures, coronoid fractures (if the fracture is large enough for fixation), and the LUCL. The elbow is assessed throughout the arc of motion for stability, and gentle stress view fluoroscopic scans are taken. If this fails to restore stability, then the medial collateral ligament may be addressed. If the elbow remains grossly unstable, a static external fixator may be placed. The pins are placed under direct visualization to avoid injury to major peripheral nerves. The fixator is placed such that the elbow is maintained in joint for a period of 4 weeks. Typically, it is removed in the operating room. First the bar is disconnected and the elbow is examined under anesthesia for instability. If it remains unstable, the bar is reconnected; however, in most cases, the elbow is now stable and the fixator is disassembled.

Postoperative Care and Rehabilitation.

Postoperatively, it is ideal if the radial head fixation is stable enough to permit early motion. If ligament injury is absent and the injury represents an isolated radial head fracture treated with stable fixation or implant arthroplasty, we typically place the patient in a splint and sling for comfort for a few days and initiate gentle range of motion exercises within a few days. If there has been an associated ligament injury, such as an LUCL and/or medial collateral ligament that has been repaired, then the patient is generally immobilized in a splint at 90 degrees in pronation (for LUCL repair), supination (for medial collateral ligament repair), or neutral (if both have been repaired), and subsequently allowed to start early flexion-extension motion provided stability permits it, with avoidance of terminal extension and forearm rotation. Pronosupination is permitted when the elbow is flexed greater than 90 degrees. At the 6-week mark, if full motion has not yet been achieved, one can consider nighttime extension splinting.

The role of and compliance with heterotopic ossification (HO) prophylaxis regimens remains a subject of discussion. In patients who can tolerate nonsteroidal antiinflammatory drugs (NSAIDs) and have no renal or gastrointestinal (GI) contraindications, indomethacin sustained-release 75 mg daily for several weeks may play a role particularly in the setting of radial head replacement and in those who may be prone to HO (head injury, history of HO). Other factors associated with HO formation include presence of bony debris, hematoma, increasing duration of surgery and dissection.

Use of external beam irradiation (700 cGy in a single dose within 24 hours of surgery) as HO has been described but use is reserved for selected cases as a recent series suggests increased nonunion risk.

Surgical Anatomy.

The olecranon is subcutaneous and is readily exposed surgically. The ulnar nerve is adjacent to the olecranon. Although ulnar neuritis following a simple olecranon fracture is believed to be uncommon, it is important to document the status of the ulnar nerve in the initial examination and subsequent examinations. The olecranon and coronoid process form the articulation with the distal humeral trochlea and confer bony stability and facilitate motion. The triceps attaches via a broad tendon insertion to the olecranon.

When surgical repair of the olecranon is performed, the surgeon should be aware that there is normally a “bare area” free of cartilage in the joint surface between the coronoid and olecranon tip. This area is exploited as the site of osteotome or saw exit when an olecranon osteotomy is performed. If the surgeon is unaware of this anatomic finding, structurally important portions of the olecranon might inadvertently be discarded during fixation of an olecranon fracture.

Positioning Techniques.

Positioning of the patient can be performed supine, prone, or lateral.

If the patient is supine, the arm may be draped over the chest and the bed “airplaned” to give the surgeon easy access to the arm. Often, an additional assistant is required to hold the arm in place and the anesthetist should confirm that the patient’s arm or surgeons’ hands do not disrupt the patient’s endotracheal tube, face, or body lying under the drapes. Lateral positioning is often helpful as it obviates the need for one assistant dedicated to stabilize the arm. The patient is placed on a beanbag, secured to the bed, and the arm placed over an arm holder. One of the authors (JEA) uses both lateral and supine positioning in her practice depending on the patient’s body habitus and the availability of assistants, while the other author (SPS) prefers supine positioning in all cases. A tourniquet is applied to the upper arm. Occasionally a patient will have a contraindication to tourniquet in the upper arm (e.g., presence of an active arteriovenous fistula). Infiltrating the skin with 1% lidocaine 1 : 100,000 with epinephrine is a helpful alternative to limit bleeding and limit the amount of anesthesia required; it should be remembered, however, that maximal vasoconstriction induced by the epinephrine occurs at 25 minutes after injection.

A mini C-arm unit provides intraoperative imaging and limits radiation exposure to the patient and surgical team. Prior to prepping and draping, the ability to obtain good images of the elbow in multiple planes is confirmed. The authors prefer general anesthesia during the procedure to facilitate patient comfort as position may be awkward otherwise.

Surgical Approach.

A straight incision is preferred, centered slightly medial to the midline of the posterior elbow. Full-thickness flaps are raised. In the setting of preoperative symptoms, the ulnar nerve is decompressed. The fracture is exposed, and following removal of hematoma, the fracture is inspected for final determination of treatment.

Reduction Techniques.

Provisional fixation may be applied with K-wires or pointed bone reduction clamps. It is helpful to use the intact distal humerus as a template for appropriate reduction.

Fixation Techniques.

Surgical options are described here.

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    Fragment excision: Excision and repair of the triceps tendon to the distal fragment is most appropriate for small proximal fragments, osteoporotic or comminuted fractures, and in the setting of low demand or elderly patients. The potential advantages of this technique include the absence of hardware (which may be prominent in the setting of ORIF) and obviating the need for bony healing. Easily up to 30% of the olecranon or more may be excised without implications on stability; some series suggest up to 80% may be excised. It is important to realize that the anterior stabilizers including the coronoid must be intact to consider excision of the proximal olecranon fragment lest instability occur postoperatively.

    
    
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    Following excision, the triceps is reattached to the bone via suture anchors or bony tunnels. Although the correct site for reattachment has previously been described as at the joint surface level, improved extension strength and a stable elbow have resulted after reattachment at the dorsal cortex of the ulna. Following wound closure, the elbow is immobilized for 4 to 6 weeks postoperatively.

    
    
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    Open reduction and internal fixation: Options include tension band wiring constructs, intramedullary devices, and plate and screw constructs. Tension band wiring with fine-gauge wire constructs with K-wires or cancellous screws can be a cost-effective and stable construct for fixation of noncomminuted fractures that do not have distal extension into the coronoid region. Intramedullary locking nail devices have been introduced as a low-profile option for fixation. Many manufacturers make purpose-made low-profile precontoured plating systems for fixation of olecranon fractures. Plate and screw constructs are the most appropriate fixation method for fractures with overt comminution, multiple fragments, or those with extension distal to the level of the coronoid.

    
    
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    Tension band wiring: The authors prefer K-wires that engage the anterior cortex to K-wires that traverse down the medullary canal or to use of a cancellous screw. Anterior engagement of the K-wires optimizes fixation and prevents rotation. Tension band wiring should be avoided in the setting of associated elbow instability or complex fractures of the elbow, in comminuted fractures, or those with distal fragments. The fracture is exposed and visualized to ensure that tension band fixation is an appropriate choice. The fracture is provisionally reduced and parallel 0.045- to 0.062-inch K-wires are driven from the proximal fragment obliquely into the distal fragment exiting anteriorly, avoiding overpenetration of the anterior cortex. Following appropriate positioning, the K-wires are backed out 5 to 10 mm so that the proximal end can be bent and impacted into the bone.

    
    
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    A hole for the tension band wire(s) is drilled perpendicular to the long axis of the ulna transversely with a 2.0- to 2.5-mm drill bit at the transition region at which the flatter proximal ulna becomes more triangularly shaped distally. The hole is placed sufficiently anterior that wire breakage of the dorsal cortex is unlikely. A 20-gauge wire is chosen and passed through the bony hole with aid of an angiocatheter or by hand, and a second wire is passed behind the triceps and just proximal to the K-wires using an angiocatheter needle. The wire ends are crossed over the dorsal ulna in a figure-of-eight and the two ends are twisted together on each side. A needle driver grasps and applies traction and twists each wire construct to tighten the wires simultaneously. The wire ends are cut and impacted into an area where they will not be prominent. As an alternative, two 22-gauge tension band wire constructs may be used instead of the single 20-gauge construct to decrease the prominence of the fixation construct. The K-wires are bent 180 degrees, cut, and impacted to capture the wire(s). Fluoroscopic images are obtained to ensure appropriate fixation and care is taken to ensure that the K-wires do not overpenetrate the anterior cortex ( Fig. 46A-7 ).

    
    

    
    

    
    

    

    
    

    
    

    Tension band wiring for this olecranon fracture ( A ) provided stable fixation ( B ).

    
    

    (Copyright JE Adams, MD.)

    
    
    
    
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    Plating: Following exposure of the fracture, provisional fixation is applied. The plate is chosen and applied to bone. Most precontoured systems have a proximal curve to the plate to allow the plate to capture the proximal olecranon and get as many screws as possible in the proximal fragment. The triceps tendon may be split over the proximal olecranon tip so that the plate can be apposed closer to the bone; however, although the plate appears to the eye flush with the proximal olecranon and triceps tendon on visual inspection, the radiographic images will have an apparent gap between the proximal plate and bone, which represents the soft tissue between the bone and plate, and is normal. Many systems have targeting fixation guides to allow for use of locked screws, particularly proximally, to optimize fixation in osteoporotic bone or when bicortical fixation is not possible. Most plating systems have a long oblique screw that engages the proximal and distal fragment, and typically exits the anterior cortex of the coronoid, which is more biomechanically favorable than screws that follow the medullary canal from the proximal fragment ( Fig. 46A-8 ).

    
    

    
    

    
    

    

    
    

    
    

    Open reduction and internal fixation (ORIF) with plate and screws resulted in stable fixation in this osteoporotic olecranon fracture.

    
    

    (Copyright JE Adams, MD.)

    
    

  
  

Pitfalls and Avoidance of Complications.

Complications include overpenetration of the anterior cortex in the setting of tension band fixation with K-wires or with drilling for screw placement. It is important to obtain good fluoroscopic images to ensure this does not occur. In addition, following completion of fixation, the elbow should be ranged in the flexion, extension, and pronosupination arc to ensure that a full arc of motion is possible (and there is not hardware impinging) and that there is no crepitans in the joint. Particularly with the proximal screw holes of plate and screw constructs, hardware may be intraarticular, and most constructs have locking options to allow for unicortical fixation. Likewise, when inspecting intraoperative images, one should remember that the cross section of the olecranon is triangular, meaning that there is a central peak with valleys on the joint on the medial and lateral side. Thus, on the lateral view, screws may appear to be in bone, but can in fact be in the joint.

Management of Intraoperative Problems.

Intraoperatively, surgeons should be prepared to revise their fixation plan if necessary. In some cases, unanticipated comminution or fracture extension may cause the surgeon to favor plate fixation over tension band wiring.

Postoperative Care and Rehabilitation.

Following fixation of the fracture, the wound is closed in layers and the elbow is splinted in mid flexion. Provided that stability of fracture fixation is satisfactory, range of motion exercises are initiated within a few days. The patient is seen within a few days to a week for range of motion assessment and wound inspection. A supervised physiotherapy program may be helpful particularly for patients who are hesitant to move the arm. Radiographs are obtained and repeated at 6 weeks and until bone healing is complete.

Surgical Anatomy.

The coronoid process extends medially and proximally from the ulna, with several facets that serve to deepen the articular cup that the humerus rests in. The radial head and coronoid serve as a bony constraint to subluxation of the elbow; the coronoid in particular protects against varus instability of the elbow. The proximal ulna is narrower than the distal humerus; on the lateral side the radial head articulates with the capitellum and the coronoid at the proximal radioulnar joint; medially, the coronoid articulates with the humeral trochlea and flares medially to match the humeral width via the sublime tubercle. Thus, approximately 60% of the coronoid in this medial extension is unsupported by the proximal ulnar region, which makes it vulnerable to fracture. In addition, the anterior band of the medial collateral ligament (MCL), which protects the elbow against valgus stresses, inserts on the sublime tubercle. Proximity of the ulnar nerve and the overlying flexor pronator muscles and nearby MCL make surgical approaches to the coronoid challenging.

Positioning Techniques.

The patient is generally positioned supine as described in the radial head fracture fixation section. This allows for the arm to be draped over the body or placed abducted from the body and with the shoulder internally rotated with the forearm placed on an arm board.

Surgical Approach and Fracture Reduction and Fixation.

Surgical approach to anterolateral or tip fractures: If the radial head fracture is approached laterally, and a sizable tip or anterolateral fracture is present (>5 mm) then surgical stabilization of the coronoid fracture can be performed through the radial head defect. Commonly, headless, cannulated screws are passed up into the fragment from the dorsal surface of the ulna with aid of fluoroscopy and a targeted drill guide, such as an anterior cruciate ligament (ACL) guide. Although small fracture fragments have been sutured to the rest of the coronoid, the end result of stabilization of fracture fragments with suture is minimal, and they may often be ignored or excised provided that the elbow is stable.

Anteromedial fractures: Operative treatment includes an examination under anesthesia and fluoroscopy to confirm the direction and pattern of instability. Surgical management involves fixation of the anteromedial fracture and addressing the lateral instability with repair of the collateral ligament. Occasionally fragments are too small and comminuted for fixation, and a static fixator may be applied to resist varus forces and allow the coronoid to heal.

The elbow may be approached with either a single posterior incision with elevation of flaps medially and laterally or via two separate incisions on the medial and lateral sides (authors’ preference). On the medial side the ulnar nerve is identified and protected. It is decompressed but left in situ. The coronoid is approached via the “floor of the cubital tunnel,” and from distal working to proximal ( Fig. 46A-11 ). The flexor carpi ulnaris (FCU) and flexor pronator group muscles are elevated from the ulna distally to proximally. As one proceeds, the sublime tubercle is palpated and by working distal to proximal, the anterior band of the MCL can be identified and preserved as the coronoid is identified and exposed.

The coronoid may be approached by retracting the ulnar nerve.

If the fracture is of sufficient size, fixation can be achieved by screws aimed from dorsal to anterior; alternatively a plate may be used as a buttress in the setting of comminution.

Following rigid fixation of the coronoid, stability is again assessed under fluoroscopy. Rarely, if the elbow is stable, the LUCL may not need to be addressed. However, if there is any suspicion of subluxation, a low threshold to address the LUCL is held. A second lateral incision may be made and the Kocher interval is exposed. Typically, the LUCL avulses off of the lateral epicondyle; it may be sutured and repaired to the lateral epicondyle with bony tunnels or suture anchors. Following fixation, the elbow is again ranged and gently stressed under fluoroscopy. If there is any residual instability, it is better to apply a static external fixation to augment the fixation rather than risk recurrent or residual instability.

Basal fractures: If there is an associated radial head fracture, this is rigidly fixed or replaced; if it is replaced, this may be used as a window to facilitate reduction of the coronoid. However, most commonly, the basal fracture will require a separate medial exposure as described in the anteromedial fracture section. When fixing these fractures, attention is paid to elevation and reduction and fixation of central impacted fragments to restore the anterior restraint to the humerus and restoration of the sublime tubercle fragment containing the MCL insertion. Fixation is typically obtained by small screws or plate and screw constructs or some combination of the two.

If there is an associated transolecranon injury, the fracture may be repaired with access via the olecranon fracture ( Fig. 46A-12 ). The proximal olecranon fragment is retracted proximally, exposing the coronoid and allowing for fixation usually with small headless or buried headed screws. The olecranon fracture can then be fixed in the usual fashion with a plate and screw construct.

Fractures of the coronoid in which an olecranon fracture is also present allows exposure and fixation of the coronoid through the olecranon defect.

Pitfalls and Avoidance of Complications.

During surgical fixation with approaches from the medial side, the fracture should be exposed from distally to proximally. This allows the surgeon to “creep up” on the fracture without inadvertently injuring the collateral ligament. The ulnar nerve should be carefully protected during the case. The fracture fragment may be fixed with a buttress plate.

Management of Intraoperative Problems.

An examination of the patient while under anesthesia as a first step during the procedure is helpful to identify injured structures and to determine which structures will need to be addressed during the procedure. It is important to ensure that the patient leaves the operating room with the elbow in a stable arc of motion and with a congruent reduction. It is better to apply an external fixation with the elbow congruently reduced than risk redislocation or residual malalignment.

Typically this is left in place for 4 weeks, then removed in the operating room. Prior to removing the pins, the connecting bar is disassembled, leaving the pins in bone. The elbow is then examined under fluoroscopy to determine if it remains reduced and to inspect arc of motion. If the elbow continues to be unstable, the bar connectors may be reapplied and fluoroscopy confirms the elbow is locked in a reduced position. If the elbow is stable, the pins may be removed. A manipulation under anesthesia may be performed if indicated.

The authors do not favor hinged elbow fixators, which have some inherent disadvantages (including difficulty of application and cost), and see no advantage to them over static fixators.

Postoperative Care and Rehabilitation.

Rehabilitation of the elbow is contingent on the stability of the fixation construct and the elbow joint itself, which was obtained intraoperatively. If the fixation construct is stable to allow early motion, this is ideal. The motion allowed must be in an arc in which the elbow remains congruently reduced and does not subluxate. Although a goal of surgery is to achieve sufficient construct integrity to mobilize the elbow, joint stability should not be sacrificed to prematurely mobilize the elbow. In addition, in some cases in which a stable joint cannot be achieved by other means, the elbow may be congruently reduced and an external fixator applied.

Surgical Anatomy.

Stability to the elbow joint is conferred by the anterior and posterior capsule, the medial and lateral collateral ligament complexes, and bony congruity, and dynamic stability is provided by actions of the muscles crossing the joint. On the medial side, the MCL includes the anterior oblique ligament, the posterior oblique ligament, and the transverse ligament. The anterior bundle of the MCL is the most important stabilizer to valgus stresses. It has two bands, which both arise from the anterior inferior medial epicondyle. The anterior band inserts on the sublime tubercle while the posterior band inserts along the semilunar notch. On the lateral side, the lateral ligament complex includes the radial collateral ligament, the LUCL, the annular ligament, and the accessory lateral collateral ligament (LCL). The LUCL serves as the major lateral ligamentous stabilizer. It arises from the inferior aspect of the lateral epicondyle and inserts on the crista supinatoris. It has near isometry during the flexion-extension arc. The annular ligament wraps about the radial head and functions to stabilize it. The annular ligament arises and inserts on the anterior and posterior margins of the lesser sigmoid notch. Because the radial head has an eccentric shape, the anterior leaf of the ligament becomes tight in supination and the posterior portion becomes tight in pronation.

Positioning.

In general, the patient is positioned supine with an arm table or arm board, unless the concomitant injuries are better addressed with other positioning. It is important to make sure that good fluoroscopic images can be obtained during the procedure. The arm is prepped from fingertips to axilla in case an external fixation device needs to be used.

Surgical Approach and Reduction and Fixation.

An examination of the patient under anesthesia using fluoroscopy as a first step during the procedure is helpful to identify injured structures and to determine which structures will need to be addressed during the procedure. In the setting of a “terrible triad” injury, the radial head and coronoid are fractured and the lateral ligament disrupted. Attention to a stepwise approach fixing the radial head, addressing the coronoid fracture if possible, and repairing the lateral collateral ligament will often restore stability; the MCL is addressed if necessary, and an elbow fixator may be applied if stability is not achieved by other means.

The surgical approach to the LUCL is detailed in the section on radial head fractures. In general in the acute setting, the LUCL is avulsed from the lateral epicondyle, and gentle palpation of the extensor apparatus may reveal the defect that can be exploited for exposure between the anconeus and ECU (Kocher approach). Any radial head pathology is addressed and then the ligament is repaired to bone using suture anchors or bony tunnels. It is important to keep in mind the origin point of the collateral ligament, which is at the central aspect of the “spool” of the capitellum. There will often be a “bare” area or “bald epicondyle” from which the tissue has avulsed. A suture anchor may be placed in this site and locking stitches used to secure the ligament. Alternatively, bony tunnels with drill holes exiting the posterior aspect of the epicondyle may be used and the ligament and associated tissue prepared with a running locking stitch. The sutures limbs are passed through the bony tunnels and tied over a bony bridge. It is important to tension and tie sutures when the elbow is congruently reduced.

On the medial side, the MCL is often avulsed together with the flexor pronator group. In such situations, the flexor pronator group and MCL are repaired to the epicondylar origin with bony tunnels or suture anchors as described earlier for the LUCL. In the authors’ experiences, it is rare to need to address the medial ligament, although it is commonly torn.

It is important to ensure that the patient leaves the operating room with the elbow in a stable arc of motion and with a congruent reduction. It is better to apply an external fixation with the elbow congruently reduced than risk redislocation or residual malalignment. The external fixator should be applied through open skin incisions, particularly proximally where the radial nerve is vulnerable. Direct visualization of the proximal pin sites is made and the external fixator is applied.

Typically this is left in place for 4 weeks, then removed in the operating room. Prior to removing the pins, the connecting bar is disassembled, leaving the pins in bone. The elbow is then examined under fluoroscopy to determine if it remains reduced and to inspect arc of motion. If the elbow continues to be unstable, the bar connectors may be reapplied and fluoroscopy confirms the elbow is locked in a reduced position. If the elbow is stable, the pins may be removed. A manipulation under anesthesia may be performed if indicated.

The authors do not favor hinged elbow fixators, which have some inherent disadvantages (including difficulty of application and cost), and see no advantage to them over static fixators.

Pitfalls and Avoidance of Complications.

In the setting of a radial head fracture where ligament structures are torn, it becomes more difficult to appropriately choose a radial head implant size and the tendency becomes one of choosing a too large implant to try to restore stability to the elbow. This should be recognized and the appropriately sized implant obtained. It is helpful to use the native radial head as a guide and to carefully examine the fluoroscopic views. It can likewise be difficult to appropriately tension ligament repairs in the setting of a grossly unstable elbow with both sides being unstable.

Management of Intraoperative Problems.

Care to appropriately and stepwise address the injured contributors to stability of the elbow can reduce the risk of complications. It is helpful to have an external fixator available during the case if needed.

Postoperative Care and Rehabilitation.

Postoperative care and rehabilitation depends on the stability obtained intraoperatively and the structures addressed. In general, the elbow is rehabilitated with elbow in a hinged elbow brace allowing flexion but limiting terminal extension and gradually increasing extension over time. The forearm position depends on the competence of the ligament structures. If the lateral ligament structures are injured but the medial side is competent, the forearm is positioned into pronation. If the lateral structures are competent, but the medial-sided structures are injured, the forearm is placed into supination. If both the medial and lateral ligament structures have been injured, the forearm is placed into a neutral position.