TREATMENT OF BUCKLE FRACTURES

Buckle fractures of the distal radius are common in children. Traditionally, this type of fracture has been treated with a period of immobilization in a short-arm cast. True buckle fractures are not at risk for displacement, and many practitioners choose to put patients in a removable splint rather than in a cast. Several recent studies have compared casting and splinting in terms of patient comfort and satisfaction, risk for complications, and cost. These studies all illustrate that children with buckle fractures have excellent outcomes regardless of whether they are treated with a splint or with a cast.

Davidson and coworkers³ surveyed specialists in England and found that 78% of emergency department doctors treated patients with distal radius buckle fractures with molded plaster splints. Orthopedic consultants/specialists tended to use casts. In addition, they randomized 201 patients with buckle fractures to treatment with a premade wrist splint or a short-arm plaster cast. All fractures were well-healed 3 weeks after injury without radiographic evidence of deformity. The follow-up rate was lower for patients who were splinted. A cost-benefit analysis showed that splint treatment was approximately half as expensive as cast treatment (assuming the splinted patients are not seen in follow-up).³ In a randomized, controlled study by Plint and coworkers,⁴ patients with distal radius or ulna buckle fractures were treated with either a short-arm plaster cast or a molded plaster backslab/splint. Parents and patients were asked to fill out an activities questionnaire at weekly intervals for 4 weeks and to attend a follow-up visit at 3 weeks. Children who were treated with splints had an easier time with writing and bathing, and had an earlier return to activities. No complications occurred in either group; however, five children in the cast group required replacement of their casts.⁴ West and investigators⁵ performed a similar study in children with distal radius buckle fractures. They randomized 39 patients to treatment with a soft bandage or a cast. Investigators instructed patients in the former group to wean out of the bandage when they felt comfortable doing so. Bandaged patients regained wrist flexion and extension more quickly. No complications were reported in either treatment group.⁵

CAST TYPE AND POSITION

Many casting methods have been used to maintain the position of pediatric forearm fractures. Investigators have attempted to determine whether factors such as cast molding, forearm and elbow position, and extension of cast above the elbow influence the rate of fracture reangulation and thus outcome.

Cast index is the ratio of cast width on lateral radiograph to the width on anteroposterior (AP) radiograph. Chess and researchers⁶ have identified 0.7 as the optimal cast index based on measurements of the pediatric forearm. This group performed a retrospective analysis of 558 distal third forearm fractures requiring closed reduction; patients were immobilized in short-arm casts. All of the patients with significant angulation had “poor cast molding”; unfortunately, this phrase was not clearly defined, nor did the examiners describe the criteria for remanipulation.⁶ Bhatia and Housden⁷ reviewed 144 charts retrospectively and followed 34 children prospectively. All patients had forearm fractures requiring closed reduction. They measured cast index and defined a padding index (ratio of padding diameter on lateral radiograph to interosseous space on AP radiograph). The authors looked for redisplacement 1 to 2 weeks after injury and defined this as angulation of greater than 20 degrees and/or translation greater than 50%. The mean padding index for the group with redisplacement was 0.42 compared with 0.11 for the group without redisplacement. The redisplacement group mean cast index was 0.87; the mean cast index for patients without redisplacement was 0.71. Both sets of findings were statistically significant with P values less than 0.005.⁷

Boyer and researchers⁸ conducted a prospective trial randomizing 100 patients with distal third forearm fractures to be casted with the forearm in pronation, supination, or neutral position. One patient casted in supination and one casted in pronation had significant loss of reduction. In their study, cast index did not correlate with residual angulation at follow-up. Bochang and coworkers⁹ managed one group of children with forearm fractures treated with the elbow in extension and compared them with a group at another center treated with flexed-elbow casting. In the flexed-elbow group, the rate of redisplacement was 17.6%. None of the children in the extended-elbow group had significant angulation on repeat radiographic examination. Other investigators who had looked at extended elbow casting in small retrospective studies also found low rates of redisplacement.^10,11

Two prospective, controlled trials have compared long- and short-arm plaster casts for the treatment of distal forearm fractures. Bohm and investigators¹² randomized 102 skeletally immature children with displaced distal third forearm fractures randomized to be placed in a long- or a short-arm cast. Casts were well molded with an average cast index of 0.71. There was actually a greater rate of need for remanipulation in patients treated with long-arm cast; this difference was not statistically significant. Webb and researchers¹³ had similar finding when they randomized 127 children with displaced distal third forearm fractures to be placed in short- versus long-arm casts. They found no difference in angulation or displacement at follow-up. Patients with long arm casts reported more difficulty in performing activities of daily living.

SEDATION

Physicians have used many different techniques and medications to provide anesthesia for reducing forearm fractures in children. In the emergency department setting, anesthetic regimens must provide safe and effective analgesia and anxiolysis without a prolonged recovery time. Parents and patients often prefer deep sedation to local anesthesia because they feel more comfortable with the idea that they will be completely unaware of the fracture reduction or will have amnesia for the event. However, recent studies have shown that regional anesthesia methods such as hematoma and nerve blocks can be effective in children. These methods offer the advantage of quicker recovery times and decreased monitoring.

Luhmann and researchers¹⁴ randomly assigned 102 children who required closed reduction of forearm fractures to receive either nitrous oxide (NO) and hematoma block or intravenous ketamine and midazolam. Videotapes of the fracture reduction were reviewed by an investigator and scored using a behavioral checklist. Both groups had low scores indicating good pain control, but pain scores were significantly lower for the group that received NO and a hematoma block (P = 0.02). Recovery time was less for children in the NO group. Children who received ketamine and midazolam had a greater rate of nightmares, hallucinations, and ataxia; otherwise, complication rates and side effects were similar.¹⁴ In Evans and colleagues’¹⁵ randomized, prospective study, children treated with NO had similar pain scores during fracture reduction as children who were given an intramuscular injection of meperidine and promethazine; the patients treated with NO were significantly more likely to report they would choose the same agent again for anesthesia. Gregory and Sullivan¹⁶ compared NO sedation with Bier block and found no significant difference in pain scores. In their study, one Bier block failed because of accidental deflation of the blood pressure cuff.

Axillary nerve block is another alternative to deep sedation. Kriwanek and coauthors’¹⁷ compared pain control in children receiving an axillary block and those treated with intravenous ketamine for forearm fracture reduction. Both groups of patients were given midazolam in this study. Examiners did not detect a significant difference in behavior scores between the two groups. However, two patients in the axillary block required supplemental anesthesia, and patient satisfaction was lower for this method.

Davidson and coworkers¹⁸ compared prilocaine and lidocaine as intravenous agents for Bier block in 279 patients undergoing forearm fracture reduction. They found that 90% of patients who received lidocaine had no or minimal pain as opposed to 78% in the prilocaine group.

FIXATION OF FRACTURES

Most pediatric forearm fractures are treated with casting with or without prior closed manipulation. Skeletally immature patients have the capacity to significantly remodel bone at the site of fractures. A certain degree of angular deformity and displacement are acceptable because of the known potential for bony remodeling. Jones and Weiner¹⁹ retrospectively evaluated 730 children with forearm fractures and found that only 12 patients required fixation, indicating that the treatment of this type of fracture is usually nonsurgical. However, a subset of pediatric forearm fractures exists that are either irreducible or susceptible to redisplacement after reduction. These fractures will require some type of fixation. Because children rarely require intervention beyond closed reduction of their forearm fractures, there are no large, randomized trials comparing the various methods of fixation.

Several authors have published case series that illustrate that intramedullary fixation of forearm fractures generally yields excellent results. In these studies, complication rates, including neuropraxias, superficial and deep infections, refracture, lost reduction, and persistent angulation, range from 8% to 28%.^20–26 In two recent articles, authors have reported compartment syndrome as a complication of intramedullary fixation. Yuan and investigators²⁷ retrospectively analyzed data from 285 patients with forearm fractures. None of the 205 patients treated with closed reduction and casting experienced development of compartment syndrome. However, 6 of the 80 patients (7.5%) treated with intramedullary fixation experienced development of compartment syndrome; none of these patients had a high-velocity mechanism of injury. The increase in compartment syndrome rates for patients managed surgically was significant with a P value less than 0.001. Increased time in the operating room for fracture fixation was associated with a greater rate of compartment syndrome (P 5 0.01).²⁷ Kapoor and colleagues²⁸ looked retrospectively at 50 children who underwent flexible intramedullary nailing of forearm fractures. Two patients in their series developed compartment syndrome; both of these patients had a high-energy mechanism of injury.

In two retrospective comparative studies, investigators compared elastic stable intramedullary nailing with Kirschner wire fixation in children with diaphyseal forearm fractures. No significant differences in complication rates were found, as would be expected in both of these intramedullary methods of fixation. In Majed and Bacos’ study,²⁹ all patients had excellent functional outcomes. Calder and coauthors³⁰ found a clinically evident limitation in forearm rotation in 11% of their patients; however, they did not quantify range-of-motion measurements in their records.

Retrospective comparative studies have also been used to examine the difference in outcomes between patients who undergo intramedullary fixation versus plate fixation of their forearm fractures. Fernandez and researchers³¹ reviewed records of 45 patients who underwent elastic stable intramedullary nailing of their middle-third and transitional zone forearm fractures, and compared the results with those of 19 patients who had plate fixation of their fractures. No significant difference in complication rates was found between the two groups. However, patients with plate fixation had longer hospital stays, longer time under anesthesia, and worse cosmetic results. Similarly, Van der Reis and colleagues³² compared results from the charts of 23 patients who had Rush rod fixation of their diaphyseal both-bone forearm fractures with those of 18 patients whose fractures were fixed with plates. No significant difference was found in complication rates or functional outcomes. The authors did note that two patients in the intramuscular fixation group had mild rotational deformities; this type of deformity did not occur in any patients in the plate fixation group.³²