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.