Peter Kloen and David C. Ring
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Surgeries for pain or deformity are less satisfying and not recommended.
Posterior Malunion or Nonunion without Instability Patients that are functioning well despite malunion can be managed nonoperatively. Pain and limitation of mo- tion lead to operative intervention in most patients.5 The ulna is either osteotomized or the nonunion débrided, a posterior contoured plate applied, bone graft used as needed, and the radial head is addressed as needed (Fig. 17–1C,D).
Posterior Malunion or Nonunion with Instability If there is subluxation or dislocation of the elbow concomi- tant with malunion or nonunion the situation is far more complex.5,7There may be a coronoid fracture of coronoid deficiency that needs to be addressed (Fig. 17–2A). If inad- equate fixation is obtained, instability will develop with subsequent failure of hardware (Fig. 17–2B). The radial head must be repaired or replaced and the ligaments must be repaired. When treated at a subacute or chronic stage, these repairs will usually need to be protected with hinged external fixation.
Figure 17–1 (A)A 51-year-old woman was treated with initial fixation of a posterior Monteggia with a laterally placed 3.5-mm dynamic com- pression plate. (B)Five weeks later, she was referred with failed fixa- tion and recurrent posterior luxation of the radial head. (C,D)Revision of fixation with a dorsally applied 3.5-mm pelvic reconstruction plate resulted in a congruent elbow with an excellent result. (Courtesy of David L. Helfet, MD.)
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Surgical Treatment
Posterior Malunion or Nonunion without Instability If the ulnohumeral joint is concentrically reduced and sta- ble, the situation is straightforward. In most patients the problem is identified prior to solid fracture healing. With the patient supine or in the lateral position, the arm is prepped and draped. We generally use a sterile tourniquet to increase the operative field. The iliac crest is prepped and draped as well if autogenous bone graft is needed.
The prior incision is opened and extended proximally.
Previous surgery around the elbow warrants a careful dissection to find the ulnar nerve first. The ulnar nerve
is identified proximally and followed distally through Osborne’s fascia. If ulnar nerve symptoms are present before the index procedure, an external neurolysis can be considered followed by an anterior subcutaneous or sub- muscular transposition. Prior loose internal fixation is then removed and the fracture site identified and mobi- lized either via osteotomy or by débriding the nonunion site of callus and fibrous tissue. Cultures are obtained after which time intravenous antibiotics are given (if the tourniquet is inflated at that time we generally give an- tibiotics immediately prior to releasing the tourniquet).
After thorough débridement using drills, curettes, and rongeurs a temporary stabilization of the ulna is obtained Figure 17–2 A 74-year old woman fell on her right arm. (A)Fractures of the radial, olecranon, and coronoid were seen. (B)Initial fixation was done with Kirschner wires and tension band and one lag screw into the coronoid fragment was insufficient. Two weeks after the ini- tial surgery, a revision was done. (C)Via a posterior approach the shaft of the ulna was reduced to the large coronoid fragment and a lag screw was placed. (D)A contoured 3.5-mm dynamic compression plate was then contoured to curve around the olecranon tip. (E)The fracture healed with good alignment with a stable ulnohumeral articu- lation. A good functional result was obtained. (Courtesy of Jesse B.
Jupiter, MD.)
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with smooth Kirschner wires (K-wires). Next, a lateral in- terval between the anconeus and extensor carpi ulnaris, or more anteriorly between the extensor carpi radialis brevis and the extensor digitorum communis, is developed. The radiocapitellar proximal radioulnar joint is cleared to accept the relocated radial head. If the radial head is frac- tured and not salvageable, it should be excised. Consider- ation is given to replacing the radial head if there is any possibility of ulnohumeral instability.
The ulna is stabilized with a 3.5-mm limited contact dynamic compression (LCDC) plate or 3.5-mm locking compression (LC) plate applied to the dorsal surface of the proximal ulna and contoured to wrap around the ole- cranon process (Fig. 17–2C). Recently, precontoured plates for the olecranon have become commercially avail- able (Accumed, Beaverton, OR). The proximal contour increases the number of screws in the proximal fragment.
In addition, the most proximal screws are orthogonal to the more distal screws, creating an interlocking construct.
Distally the plate lies on the apex of the ulnar diaphysis and the interval between the extensor and flexor carpi ulnaris muscles is incised just enough to get the plate touching periosteum. If the fracture site had delayed heal- ing, autogenous cancellous bone graft from the iliac crest or the tip of the olecranon is applied (Fig. 17–2D,E).
Posterior Malunion or Nonunion with Instability When instability is present, the coronoid, radial head, and collateral ligaments must be addressed. In subacute cases the coronoid can often be identified and repaired. The later one intervenes, the less likely this will be possible. Consid- eration can be given to reconstructing the coronoid with a fragment of the radial head of olecranon. Radiocapitellar contact should be preserved or restored. In most patients, this requires a metal radial head prosthesis. The lateral collateral ligament is reattached to the lateral epicondyle using suture anchors. The entire construct is protected with a hinged external fixator.
Complications
Posterior malunions and nonunions have been associated with loss of fixation, nonunion, continued instability, and arthrosis. Temporary ulnar neuropathy is often seen de- spite external neurolysis and/or anterior transposition.
Postoperative Rehabilitation
Patients are encouraged to do active-assisted exercises and use the arm for light daily activities within a few days of surgery. If the elbow is slow to mobilize, static progressive and dynamic splints may be used to assist with restoration
of elbow mobility. Strengthening exercises are delayed until healing is established. Hinged external fixation is removed between 4 and 8 weeks after surgery.
Results
Nonunion/Malunion without Instability
We recently reviewed 17 patients with malalignment af- ter surgical treatment of a posterior Monteggia fracture (Bado type II). Of these, 9 patients initially had a coronoid fracture. A radial head fracture was seen in 16 of 17 pa- tients (seven Mason type II, nine Mason type III) including all of the 9 patients with a coronoid fracture. There was instability with either subluxation (9 patients) or disloca- tion (2 patients) of the ulnohumeral joint. All patients were treated according to the protocol as outlined above.
Index surgery was performed at an average of 7 weeks (range: 1 to 16 weeks) after the injury. Posterior plating of the ulna was performed in all 17 patients. Bone graft was added in 5 patients. Treatment of the radial head evolved over time with the development of improved radial head prostheses and increased appreciation of its role in elbow stability. Because of ulnohumeral instability, 5 patients were treated with an external hinged fixator (Compass Hinge; Richards, Memphis, TN) as part of the reconstruc- tive procedure. At the final follow up at 59 months (24 to 130 months) all ulnar fractures had united in good align- ment with a stable ulnohumeral joint. Average ROM was 108 degrees (range: 75 to 135 degrees) with average flexion of 130 degrees (range: 100 to 150 degrees) and a flexion contracture of 22 degrees (range: 0 to 55 degrees).
Pronation and supination averaged 70 degrees (range: 20 to 80 degrees) and 64 degrees (range: 10 to 80 degrees), respectively. Results were rated as excellent in 5, good for 9, fair for 2, and poor for 1 patient according to the system of Broberg and Morrey.2
Complications that were seen after the index proce- dure were failure of coronoid fixation (1 patient), recurrent radioulnar synostosis (1 patient), elbow disloca- tion necessitating adjustment of the hinged external fixa- tor (1 patient), nonunion of the olecranon (1 patient) necessitating revision osteosynthesis and bone grafting, wound infection (1 patient, self-inflicted), and persistent ulnar nerve symptoms that needed submuscular nerve transposition (1 patient). Only 1 patient requested hardware removal of the ulnar plate.
Summary
Patients with malunited and nonunited Monteggia frac- tures often have restriction of forearm rotation, ulno- humeral instability, and incongruity of the elbow joint ch17_p170-174.qxd 1/11/08 10:16 PM Page 173
leading to arthrosis. Salvage of these malaligned Monteggia lesions can often be obtained by realignment of the ulna with a dorsally applied plate contouring around the tip of
the olecranon. Patients with instability are more challeng- ing and the result is determined by the status of the joint and other associated problems.
References
1. Bado JL. The Monteggia lesion. Clin Orthop Relat Res 1967;50:71–76
2. Broberg MA, Morrey BF. Results of delayed excision of the radial head after fracture. Bone Joint Surg Am 1986;68:669–674
3. Bruce HE, Harvey JP, Wilson JC. Monteggia fractures. J Bone Joint Surg Am 1974;56:1563–1576
4. Jupiter JB, Leibovic SJ, Ribbans W, Wilk RM. The posterior Monteggia lesion. J Orthop Trauma 1991;
5:395–402
5. Ring D, Kloen P, Tavakolian J, Helfet DL, Jupiter JB. Loss of alignment after operative treatment of posterior Mon- teggia fractures: salvage with dorsal contoured plating. J Hand Surg [Am] 2004;29:694–702
6. Ring D, Jupiter JB, Simpson NS. Monteggia fractures in adults. J Bone Joint Surg Am 1998;80:1733–1744
7. Ring D, Hannouche D, Jupiter JB. Surgical treatment of persistent dislocation or subluxation of the ulnohumeral joint after fracture-dislocation of the elbow. J Hand Surg [Am] 2004;29:470–480
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Solutions for Complex Upper Extremity Trauma ch17_p170-174.qxd 1/11/08 10:16 PM Page 174The forearm should be considered as a joint consisting of two long bones and three ligamentous restraints: the an- nular ligament complex, the interosseous membrane (IOM), and the triangular fibrocartilage complex (TFCC).
There are two articular components as well: the proximal (PRUJs) and distal radioulnar joints (DRUJs), which permit rotation of the radius on a relatively fixed ulnar axis.
If the forearm is now looked upon as a joint, diaphy- seal fractures should be considered intraarticular and therefore deserve – as in any other fracture that disrupts an articular surface – accurate anatomic reduction to guarantee full restoration of function. This same principle should be taken into consideration for the surgical recon- struction of nonunited and malunited forearm fractures.
Although open reduction and compression plate fixa- tion of forearm fractures invariably restores anatomy and function with a relatively low rate of complica- tions,1–5 surgical reconstruction of forearm nonunions and malunions represents a more difficult challenge in which despite achieving bony union, correcting defor- mity, and relieving pain, complete and symmetrical restoration of forearm rotation is difficult to obtain, but may be certainly improved to a reasonable functional arc of pronation and supination.
This is due to the frequent concomitant derangement of the PRUJS and DRUJs as well as the IOM commonly associated with the bony deformity of the nonunited or malunited forearm bones. In both scenarios, symmetric shortening of both bones may not alter the congruity of the PRUJ or the DRUJ, provided there is no significant associated angular deformity. Conversely, shortening of a single fore- arm bone with or without angular deformity will automati- cally affect the articular anatomic relationships of either the PRUJ or DRUJ. Loss of the physiological bow of the radius is responsible for limited pronation, whereas reduction of the interosseous space associated with angular or ad latus (translation) deformity leads to secondary contracture of the IOM and decreases forearm rotation.
Posttraumatic radioulnar synostosis is a less frequent complication, but its management, although currently well standardized, does not exclude recurrence in pa- tients with special risk factors.
In this chapter, we describe the current principles of management of both simple and complex diaphyseal
forearm nonunions and malunions in adults, and present treatment recommendations for both primary and recur- rent radioulnar synostosis.