Essex-Lopresti Fractures

Published on 18/03/2015 by admin

Filed under Orthopaedics

Last modified 22/04/2025

Print this page

This article have been viewed 4349 times

CHAPTER 31 Essex-Lopresti Fractures

Kathryne J. Stabile, MD, Matthew M. Tomaino, MD

Injury Pattern and Biomechanics

When a fall on an outstretched hand leads to a comminuted radial head fracture, longitudinal radioulnar dissociation (LRUD) may result if the forearm interosseous ligament (IOL) tears as well. This is often referred to as the Essex-Lopresti lesion. This injury pattern was initially described by Curr and Coe in 1946,¹ but Essex-Lopresti illustrated the importance of diagnosing longitudinal radioulnar instability.² Fracture of the radial head, disruption of the central third of the IOL, historically referred to as the interosseous membrane,³^–⁷ and injury to the distal radioulnar joint (DRUJ), contribute to loss of forearm stability. In LRUD, lack of forearm stability leads to loss of forearm rotation, decreased wrist extension, ulnar wrist pain, and elbow pain.³^–⁷ Understanding normal forearm biomechanics facilitates treatment of this challenging clinical problem.

The biomechanics of the forearm axis are best explained in terms of load transfer and stability. With use of the hand, and forceful grip, forces are transferred through the wrist to the elbow via the forearm IOL. Abnormal load transfer may result in pain secondary to abnormally high joint contact stresses at the elbow and ulnocarpal joints. As the forearm is loaded axially in compression, the IOL is loaded in tension. The IOL functions not only to transfer load from the radius to the ulna but also to pull the radius and ulna together at the proximal and distal radioulnar joints (Fig. 31-1).⁸^–¹² Numerous studies have shown that the IOL and the triangular fibrocartilage complex (TFCC) help to provide stability to the DRUJ.¹³^–¹⁷

FIGURE 31-1 The forearm interosseous ligament.

Diagnosis

With a high-energy axial load applied to the forearm through the wrist, the radial head can fracture. With enough energy, the IOL and DRUJ can also be disrupted. Injury to the IOL and DRUJ can be easily overlooked if attention is focused on the radial head fracture alone.¹⁸ After a few weeks, patients with LRUD can present with ulnar-sided wrist pain, loss of forearm rotation, and elbow pain. Physical examination will show painful rotation and ulnar deviation, forearm swelling, and lateral elbow tenderness.

Minimal radial shortening of up to 2 mm may be expected with a simple fracture of the radial head.^19,²⁰ However, greater than 2 mm of radial shortening and radial head comminution are strongly suggestive of LRUD (Fig. 31-2).²¹

FIGURE 31-2 Anteroposterior radiographs of the elbow (A) and wrist (B) in a case of acute LRUD.

Edwards and Jupiter ²² proposed a classification system for the Essex-Lopresti type radial head fractures:

Type I—radial head fractures with minimal comminution amenable to open reduction and internal fixation

Type II—comminuted radial head fractures requiring excision and radial head replacement

Type III—chronic cases with irreducible proximal radial migration

Patients presenting with a comminuted radial head may present acutely with symptomatic LRUD, but they also have the potential to develop late LRUD. Although patients with LRUD may present acutely with wrist pain and forearm swelling, this is typically not the case. Forearm and wrist films should be obtained along with elbow films. Magnetic resonance imaging and ultrasonography have also proved useful in imaging IOL tears.²³^–²⁷ Radius stability can be assessed intraoperatively by applying axial load to the radius (“shuck” test). Proximal migration of the radius in late LRUD may be frank or occult. In frank cases, LRUD is seen on plain radiographs. In occult cases, power grip and axial stress views may elicit ulnar-positive variance.^28,²⁹ Proximal migration of the radius may be fixed or reducible; distinguishing this can help guide treatment. If frank, dynamic fluoroscopic evaluation utilizing finger traps can illustrate if the deformity is reducible, then ulnar-positive variance may be “reduced” to ulnar-neutral variance. In the occult case, ulnar-positive variance is, by definition, dynamic.

Current Treatment and Surgical Technique

Traditionally, treatment approaches have focused on restoring a normal radioulnar relationship, which means restoring radial length. This has been accomplished by repair or replacement of the radial head and pinning of the radius to the ulna at the level of the DRUJ after restoration of length—to allow the IOL, TFCC attachment, and DRUJ capsule to heal. In the acute setting, the radius can usually be reduced; that is, proximal migration of the radius is not fixed and can be corrected by radial head open reduction and internal fixation (ORIF) or arthroplasty. In the late setting, however, proximal migration of the radius may be a fixed deformity requiring ulnar shortening at the wrist or use of a distraction device such as an Ilizarov frame to restore radioulnar length.

When the IOL is torn, the radial head is essential for maintaining longitudinal stability. If ORIF is not possible, radial head arthroplasty functions to share the load at the elbow and prevent proximal migration of the radius. Although Silastic radial heads have been used in the past, nonmetallic implants have been shown to collapse over time and may cause synovitis.^16,³⁰^–³³ Metallic prostheses are stiffer than Silastic ones and are more effective in preventing proximal migration of the radius.³⁴^–³⁷ However, long-term clinical results of metallic radial heads in cases of LRUD are still lacking in the literature. There may be complications due to implant loosening and dislocation and elbow stiffness and capitellar wear from oversizing the implant.

Modular radial heads offer a more anatomical design. Grewal and associates recently reported favorable short-term clinical results at 2 years with modular radial head replacement for comminuted radial head fractures.³⁷ Even though this study lacked a control group, the authors found no evidence of overstuffing and 81% did not have arthritic changes. However, the outcomes of modular radial heads in patients with Essex-Lopresti fracture-dislocations in particular remain to be seen.

Treatment of Acute LRUD

The overall goal of treatment is to restore load sharing between the radius and ulna and prevent long-term proximal migration of the radius. The structures that require attention include the radial head, the TFCC, and the IOL. The radial head should be preserved if ORIF is possible. However, comminution of the radial head may prevent repair. Therefore, restoring radial length will require metallic radial head arthroplasty (Fig. 31-3). In addition, pinning of the DRUJ for 4 weeks is recommended to allow the TFCC and DRUJ capsule to heal. Furthermore, because failure of this acute treatment strategy has significant consequences, and as the technique of open foveal reattachment of the torn TFCC has been refined, we advise a more aggressive approach to address the wrist after radial head replacement and restoration of the normal radioulnar relationship—open TFCC repair plus DRUJ pinning. This will ensure as precise a restoration of normal anatomy at the wrist as possible.

FIGURE 31-3 Anteroposterior (A) and lateral (B) radiographs after radial head replacement.

Little clinical data exist to support a clear role for reconstruction of the IOL acutely; and although suture repair of the IOL has been suggested, there are no data to suggest this is any better than just allowing the IOL to scar in once a normal radioulnar relationship has been restored. Biomechanical data suggest, however, that the IOL is necessary to unload the radial head. Acute reconstruction, in that light, may be a defensible strategy once the technical aspects of the procedure are refined.

When LRUD is unrecognized, hence untreated, restoration of radial length may not be possible. Characterizing proximal migration of the radius as fixed or reducible is critical to the decision-making in such “chronic” cases.³⁸ Traction films with finger traps may be helpful. Fundamentally, intraoperative assessment relies on whether the proximal radius can be “pushed distally” when grasped with a towel clamp. In such cases, radial head replacement is recommended. Treatment recommendations for the reducible DRUJ are the same as for the acute case. However, if the radius cannot be pushed distally, and the DRUJ reduced, ulnar shortening osteotomy or use of an Ilizarov fixator (in a staged procedure) should be used to obtain ulnar-neutral variance. As experience with metallic ulnar head replacement increases, ulnar head arthroplasty may have a role when DRUJ arthritis exists. Although ulnar impaction, DRUJ arthritis, or an irreducible DRUJ may have been treated with distal ulna resection in low-demand wrists, this should not be performed in these types of cases. Grip strength will be compromised because of radioulnar impingement, and load transfer between the hand and elbow will be even more compromised. Indeed, understanding that transverse force vectors exist at the wrist and that the forearm unit functions with the IOL to unload the proximal radius mandates that neither the distal ulna nor the radial head is ever simply resected.

Although IOL reconstruction is still considered experimental, late cases of LRUD may represent the most compelling indication for such a strategy—to improve load sharing between the radius and ulna and reduce loads on the radial head implant.^39,⁴⁰

If capitellar wear has developed in chronic cases of untreated LRUD, capitellar resurfacing may be an option at the same time that radial head replacement is performed. Little data exist to support this innovative strategy, but uniarthroplasty (Small Bone Innovations, Inc., New York, NY) may hold promise in the future for such cases (Fig. 31-4).

FIGURE 31-4 A and B, Capitellar resurfacing may have a role when radiocapitellar arthritis has developed.

IOL Reconstruction

In evaluating treatment of the Essex-Lopresti fracture-dislocation, a strategy that includes IOL reconstruction as well as radial head replacement and TFCC repair may be most attractive because historical options described earlier have provided inconsistent and, too frequently, inadequate results.^3,^6,³⁹^–⁴⁶ Because IOL reconstruction is still considered experimental, it is not typically recommended. However, reconstruction of the IOL is feasible and likely efficacious based on anatomical and biomechanical studies.

The goal of IOL reconstruction is to restore anatomical load transfer without limiting forearm rotation. Chandler and associates and Forster and coworkers have suggested that tendon graft be placed at an angle of 20 to 24 degrees to the long axis of the ulna.^47,⁴⁸ Chandler and associates also found that the IOL inserts on the radius at a point 57% proximal to the distal radius and 34% proximal to the distal ulna.⁴⁸ These findings correlate well with those of Skahen and associates⁴⁹ and Fujita.⁵⁰ Despite agreement regarding where the IOL footprint is, however, there remains debate on the graft type, placement, and reconstruction technique. Grafts such as hamstring tendons or patellar tendon have similar material properties to the IOL.^46,^51,⁵² However, these grafts pose issues with donor site morbidity.⁵³^–⁵⁷ Graft stiffness of the palmaris longus and single-bundle flexor carpi radialis have been shown to be significantly different from the intact IOL.^43,⁵² There is some clinical and basic science experience with the patellar tendon graft using a dorsal onlay technique described by Ruch and associates.⁴⁶ However, this reconstruction is nonanatomical and graft length may dictate graft placement.⁴³^–⁴⁶ Long-term clinical outcomes remain to be seen with the patellar tendon graft and onlay technique. Other authors have investigated IOL reconstruction techniques in the laboratory by placing the graft in line with the axis of rotation, but, again, this is nonanatomical and remains a cadaveric experiment.^58,⁵⁹

In our laboratory we have investigated IOL reconstruction using a flexor carpi radialis graft placed anatomically in the footprint of the IOL on the radius and ulna. We found that an anatomical single-bundle graft restored approximately 76% of the load transferred through the intact IOL. We also found that an anatomical double-bundle graft was able to restore normal forearm load transfer to that of the intact IOL.^39,⁴⁰ As favorable experience with tendon allograft for such procedures as elbow MCL and LCL reconstruction has grown, we have found that the potential morbidity of autograft use can be safely eliminated. This allows the selection of a lengthy graft such as the tibialis anterior as an alternative to the flexor carpi radialis autograft. Our proposed technique utilizes an anatomical single-bundle technique; this is expected to restore load transfer to approximately 75% of normal (Fig. 31-5). Tibialis anterior tendon graft can be anchored at the radius and ulna with biotenodesis screws (Arthrex, Naples, FL). As experience develops, a double-bundle reconstruction may become feasible, with the added benefit that biomechanical data suggest restoration of normal load transfer.

FIGURE 31-5 Proposed anatomical IOL reconstruction.

Indications

The indications for IOL reconstruction are unclear at this time but probably should include chronic cases for which intraoperative evidence of LRUD exists and for which radial head arthroplasty is planned. Regardless of whether a distal ulna procedure is required, IOL reconstruction will unload the proximal radius and diminish, if not prevent, the risk of subsequent radiocapitellar arthritis.

Contraindications

Contraindications revolve around how likely pain relief and functional restoration are with this approach as compared with creation of a one-bone forearm. In other words, if concern exists over the amount of distal and proximal radioulnar degeneration and if little forearm rotation exists, salvage alone may be advisable.

Results

We have no results to report at this time because our recommendations for surgical technique are based solely on biomechanical and anatomical studies. However, Osterman and associates ⁴⁵ treated 16 patients for chronic LRUD injuries with ulnar-shortening osteotomy and bone-ligament-bone reconstruction using a patellar tendon graft. The initial diagnoses were radial head fracture, radial head fracture with posterior dislocation, Monteggia fracture, radial head fracture with distal radius fracture, and Essex-Lopresti fracture. Interosseous ligament instability was identified an average of 10 months after radial head excision (range: 2 months to 12 years), with 75% of patients presenting within 2 years. The average ulnar variance was 3 mm (range: 2 to 5 mm) on standard posteroanterior radiographs. Other pathological processes included lunate impaction (4 patients), DRUJ arthritis (2 patients), and mild elbow arthritis (5 patients).

All patients received an ulnar-shortening osteotomy, and through the same incision a bone-ligament-bone autograft was anchored to the ulna. Through a plane beneath the extensors, the graft was tunneled and fixed to the radius at an acute angle. Grafts were tensioned in neutral to 20 degrees of supination. Concomitant procedures included radial head excision (1 patient), removal of radial head prosthesis (2 patients), wrist arthroscopy (3 patients), DRUJ resection (1 patient), Sauvé-Kapandji procedure (1 patient), and carpal tunnel release (1 patient).

Outcomes at an average of 78 months demonstrated that no patient was worse in terms of pain or function than before the surgery. Fifteen of 16 patients had improved wrist pain, 2 had worse elbow arthritis radiographically, no patient had radiocapitellar impingement, and 4 patients had knee aches with weather change. No patient needed secondary surgery to address forearm instability. Grip strength improved from 59% to 86% of the unaffected limb. Ten of the 14 patients who were employed before their injury returned to their regular work duties, whereas 3 of 14 required job modification. Initial postoperative ulnar variance was −2 mm (range: −4 mm to +1 mm) and on follow-up averaged −1.5 mm (range −3 mm to +1 mm). Complications included one ulnar nonunion, one ulnar delayed union, 1 patient with extensor tendon adhesions, and 4 patients with knee aches.