Monteggia Fracture Patterns May Dictate Treatment

Study outlines strategy for selecting appropriate treatment in pediatric patients

Jennie McKee

Closed reduction and cast immobilization may not always be the best option for treating Monteggia fracture-dislocations in children, given that loss of reduction and late instability can occur. According to William P. Hennrikus, BA, who presented results of research on the issue yesterday, a more tailored approach may yield better outcomes.

Mr. Hennrikus and his colleagues—including lead author David Ramski, BS, BM—found that selecting a treatment approach based on the ulnar fracture pattern reduced the risk of late instability and resulted in positive outcomes. Their study employed a treatment strategy developed by Ring and Waters that matched the following fracture patterns and treatments:

Plastic deformation and incomplete fractures—closed reduction and casting
Transverse and short oblique fractures—intramedullary rodding
Long oblique or comminuted fractures—open reduction and internal fixation (ORIF)

Fig. 1 Radiograph showing a mid-shaft ulna fracture with anterior radial head dislocation.

Multicenter study
The retrospective study analyzed 113 consecutive patients (age range, 0 years to 16 years) treated for Monteggia fractures at two pediatric level 1 trauma centers from 2000 to 2011. Patients had all been treated within 14 days of being diagnosed with an ulnar fracture associated with dislocation of the proximal radiocapitellar joint.

The researchers reviewed medical records and plain radiographs to obtain preoperative data, including (but not limited to) patient age, sex, and ulnar fracture location and pattern. They also collected postoperative data, including time in cast, instances of resubluxation of the radial head, instances of redisplacement or nonunion of the ulna, range of motion and pain at final follow-up, and complications that required additional unexpected outpatient, inpatient, or surgical care.

Approximately half (57 patients) received treatment that did not correspond to the ulnar fracture-based strategy, while the other half (56 patients) received care that did correspond to the strategy.

Analyzing treatment effectiveness
Failure was defined as resubluxation/redislocation of the radial head, or unacceptable ulna alignment. At follow-up (average, 23.7 weeks), the researchers found no failures among the patients whose treatment followed the ulnar fracture-based strategy.

“One hundred percent of the fractures in this group went on to successful healing without loss of ulnar fracture alignment or recurrent radiocapitellar joint instability,” noted Mr. Hennrikus.

In contrast, of the 57 patients whose care did not correspond to the ulnar fracture-based pattern, 7 patients had loss of radiographic alignment, including 5 patients with resubluxated radiocapitellar joints and 3 patients with redisplaced ulnar fractures. The failure rate among these patients was 12.3 percent (P=0.01).

Complications and unsatisfactory outcomes included ulna nonunion, compartment syndrome, nerve palsy/neuropraxia, persistent pain, and loss of motion.

One patient with ulnar nonunion had a comminuted fracture that was treated with open reduction of the radiocapitellar joint and ORIF of the ulna. Compartment syndrome developed in two patients; 3 patients experienced nerve palsy/neuropraxia, and 2 patients had persistent loss of range-of-motion or pain at final contact. These events were essentially equally distributed among patients of both treatment groups, according to Mr. Hennrikus.

Drawing conclusions

Although the retrospective study had several limitations, including researchers’ inability to obtain information about range of motion from a small number of patients at follow-up, the lack of this data did not impair their ability to conduct primary analysis.

In conclusion, Mr. Hennrikus noted that “transverse and short/long oblique ulnar fracture patterns have a higher risk of failure without initial surgical treatment,” and that recurrent instability occurred only in patients who were not treated according to their ulnar fracture pattern.

“Treatment of acute pediatric Monteggia fracture-dislocation according to ulnar fracture pattern has excellent clinical and radiographic results, with little risk for late displacement or instability,” he said.

Mr. Hennrikus’ coauthors on “Monteggia Fractures in Children: A Multi-Center Examination of Treatment Strategy and Outcomes” include David Ramski, BS, BM; Donald S. Bae, MD; Keith D. Baldwin, MD, MSPT, MPH; Neeraj M. Patel, MD, MPH, MBS; Peter M. Waters, MD; and John M. Flynn, MD.

Disclosure information: Mr. Hennrikus, Mr. Ramski, Dr. Patel—no conflicts. Dr. Bae—Cubist; Optimer; Osiris; Lippincott Williams & Wilkins; American Society for Surgery of the Hand (ASSH); Pediatric Orthopaedic Society of North America (POSNA). Dr. Baldwin—Pfizer; Journal of Bone and Joint Surgery–American. Dr. Waters—Celgene; Sangamo; Wolters Kluwer Health–Lippincott Williams & Wilkins; ASSH; POSNA. Dr. Flynn—Biomet; Wolters Kluwer Health–Lippincott Williams & Wilkins; Orthopedics Today; POSNA; Scoliosis Research Society; AAOS.

2013 Annual Meeting News
Tuesday through Friday, February 19 – 23, 2013.
http://www.aaos.org/news/acadnews/2013/AAOS17_3_22.asp