Closed reduction and casting of distal forearm fractures in children

INTRODUCTION — Childhood forearm fractures are very common and typically occur after a fall on an outstretched hand. Closed reduction and casting provides definitive treatment for displaced Salter-Harris I or II, greenstick, and complete distal forearm fractures in children and is often accomplished under sedation in the emergency department. These reductions can be performed by appropriately trained personnel or orthopedic surgeons.

Fracture reduction and casting of distal forearm fractures in children will be reviewed here. The diagnosis, assessment, and management of distal forearm fractures in children, the care of pediatric proximal or midshaft forearm fractures, and the basic principles of casting are discussed separately:

●(See "Distal forearm fractures in children: Diagnosis and assessment".)

●(See "Distal forearm fractures in children: Initial management".)

●(See "Midshaft forearm fractures in children".)

●(See "Proximal fractures of the forearm in children".)

●(See "General principles of definitive fracture management", section on 'Casting'.)

INDICATIONS — Closed reduction and immobilization should be performed only by properly trained and experienced clinicians. Reduction and immobilization are necessary for significantly displaced or severely angulated closed distal forearm fractures, including displaced complete (image 1), greenstick (image 2), and Salter Harris I or II fractures (image 3). Closed reduction followed by casting or splinting provides definitive treatment for the majority of these fractures [1].

Rarely, no trained clinician or orthopedist may be promptly available to perform closed reduction and casting of a displaced distal forearm fracture. In this situation, the managing clinician may choose to transfer the child to a facility where the fracture can undergo definitive management or, in exceptional circumstances and when the fracture poses no neurovascular risk, splint the fracture with a sugar tong and long arm splint (figure 1 and figure 2) and assure orthopedic reduction and immobilization within 24 hours.

CONTRAINDICATIONS — Contraindications to casting of distal forearm fractures by clinicians other than an orthopedic surgeon include any injury that warrants urgent evaluation by an orthopedic surgeon, especially those injuries that warrant emergency surgery.

Examples include:

●Open fractures that require debridement and definitive orthopedic care in the operating room (OR).

●Salter-Harris III, IV, or V physeal (growth plate) distal radius or ulna fractures (figure 3 and image 4 and image 5) require reduction by an orthopedist with pediatric expertise.

●Distal forearm fractures complicated by joint dislocation (wrist or elbow) or supracondylar fracture also warrant prompt involvement of an orthopedic surgeon and frequently require closed or open reduction in the operating room.

PREPARATION

Informed consent — Caregivers should provide written informed consent for closed reduction and casting. The clinician should ensure full understanding of the risks of this procedure including adverse effects of procedural sedation, potential loss of reduction despite appropriate care with the potential need for open reduction and fixation in the operating room, and the potential for cosmetic or functional adverse outcomes, depending upon the type of fracture (eg, growth arrest with Salter-Harris I or II fractures, refracture with greenstick or complete fractures, loss of wrist rotation with complete fractures). The clinician should ensure that a careful neurovascular examination precedes attempts at closed reduction. (See "Distal forearm fractures in children: Initial management", section on 'Complications' and "Distal forearm fractures in children: Diagnosis and assessment", section on 'Physical examination'.)

Sedation and analgesia — The availability of safe pediatric sedation and analgesia in healthy patients outside of the operating room allows most fracture reductions to be performed in the emergency department. Medications chosen should provide sedation and analgesia. Options for pediatric procedural sedation are discussed separately. (See "Procedural sedation in children: Selection of medications", section on 'Moderately or severely painful procedures' and "Pediatric procedural sedation: Pharmacologic agents", section on 'Propofol' and "Pediatric procedural sedation: Pharmacologic agents", section on 'Ketamine'.)

Patients undergoing procedural sedation require a careful pre-sedation evaluation. In addition, personnel who are trained in advanced airway management and not directly involved in the reduction should frequently monitor the patient during the procedure and recovery. (See "Procedural sedation in children: Preparation", section on 'Monitoring' and "Procedural sedation in children: Preparation", section on 'Pre-sedation evaluation' and "Procedural sedation in children: Preparation", section on 'Personnel'.)

Some clinicians may choose to combine procedural sedation with local anesthesia such as a hematoma or an intravenous regional block (Bier block) [2,3]. In some patients, this approach permits more expeditious manipulation of the fracture in patients who have recent oral intake and more rapid recovery. As an example, in a randomized trial of 102 children 5 to 17 years of receiving sedation and analgesia for forearm fracture reduction all of whom received oxycodone prior to sedation, nitrous oxide (N₂O) plus a hematoma block had similar efficacy for alleviating distress during fracture reduction when compared with intravenous ketamine with midazolam [2]. Children who received N₂O plus hematoma block had significantly less hallucinations, ataxia, and nightmares although vomiting occurred in approximately 25 percent of patients in both groups. Median recovery time was significantly shorter in patients receiving N₂O plus a hematoma block compared with ketamine with midazolam (14 versus 85 minutes).

The technique of hematoma and Bier blocks are discussed separately. (See "Distal radius fractures in adults", section on 'Performance of hematoma block' and "Overview of anesthesia", section on 'Intravenous regional anesthesia'.)

Parental presence — If caregivers choose to stay with the child during the procedure, they should be warned about the child's appearance during sedation, including the possibility that the child will cry out, vomit, or need airway support; the sound of moving bones during the reduction; and the possible need for multiple attempts and/or significant force to successfully reduce the fracture. In addition, they should be seated where they will be comfortable and out of the way.

Equipment — The clinician should assemble the following materials:

●Trauma scissors

●Stockinette

●Two inch cotton padding (eg, Webril)

●Two inch fiberglass or plaster casting material

●Bucket with lukewarm water

●Finger traps, if planning to use them (figure 4)

TECHNIQUES

Complete fracture reduction — A fracture is considered complete when it passes through both cortices of the distal metaphysis (distal third) of the radius and/or ulna, often with displacement (image 6). (See "Distal forearm fractures in children: Diagnosis and assessment", section on 'Complete fractures'.)

The need for closed reduction of complete distal forearm fractures in children versus casting or splinting alone depends upon patient age; whether the fracture is through the metaphyseal or diaphyseal region; and the degree of angulation, displacement, and malrotation (see "Distal forearm fractures in children: Initial management", section on 'Complete fracture'):

●Displaced fractures and those with greater than 20 degrees angulation require closed reduction and casting to ensure proper healing (image 1 and image 7).

●Isolated distal radius diaphyseal fractures with minimal lateral shift (<2 mm), dorsal angulation of less than 10 degrees, and shortening of <2 mm with minimal angulation or minimal displacement can be casted without reduction.

●Nondisplaced isolated radial metaphyseal fractures with up to 15 to 20 degrees angulation can be splinted in a sugar tong splint or casted without reduction in children under 10 years of age (image 8).

When questions about the need for reduction arise in children with complete distal forearm fractures, discussion with an orthopedic surgeon is warranted.

The steps for closed reduction of a complete distal forearm fracture are as follows [1,4-6]:

●Have an assistant grasp the extremity to apply longitudinal traction by suspending the proximal forearm. Alternatively, if an assistant is not available, the extremity can be suspended in finger traps with the elbow at 90 degrees prior to and during the reduction (figure 4).

●Apply counter traction during the reduction by slinging a sheet over the upper arm and stepping on the ends, or having an assistant apply the counter traction.(figure 4).

●If the bones are overlapping (image 1), increase the angular deformity (often to greater than 90 degrees) to disengage the fragments and open the hinge that occurs at the fracture line (figure 5A-B).

●At the same time, apply traction against countertraction from finger trap suspension or an assistant and push the distal fragment onto the end of the proximal fragment using your thumbs (figure 5A-B).

●Straighten the forearm into the reduced position (image 7).

●Maintain the reduction with a short or long arm cast. (See 'Casting' below.)

●Obtain plain radiographs to confirm adequate fracture reduction.

Adequate reduction of a complete fracture may take several attempts. Portable fluoroscopy is useful to check the adequacy of reduction during the procedure. When performed by trained and experienced providers, bedside ultrasonography may provide similar guidance of the reduction (see "Distal forearm fractures in children: Diagnosis and assessment", section on 'Point-of-care ultrasonography'). Malrotation of the radius and ulna must also be corrected by supination or pronation; rotational alignment of the radius is more important than that of the ulna. A reduced complete distal forearm fracture is prone to malposition over time. Maintaining reduction with good cast technique is essential. (See 'Casting' below.)

Once a fracture reduction is performed, the child should follow-up with an orthopedic surgeon within a week for radiographic assessment of fracture position. Subsequently, the patient is seen on a regular basis for the first few weeks to monitor for loss of reduction [1,5].

Up to 25 percent of complete fractures displace during follow-up despite adequate initial closed reduction and casting [1,7,8]. These fractures may require repeat closed reduction, cast wedging, or operative intervention. Minimal loss of reduction is often tolerated because of remodeling of bones in children. More than 50 percent initial displacement, lack of anatomic reduction, or AP to lateral diameter (cast index) <0.7 are associated with a higher risk of re-displacement [9].However, the most displacement (44 percent loss of reduction) was in the distal fractures (compared with proximal and midshaft fractures) [10].

Greenstick fracture reduction — A greenstick fracture is a complete fracture of the tension side of the cortex of the radius or ulna and a plastic deformation, or buckling, of the compression side. On radiograph, the fracture will be seen as a complete disruption on one side of the bone with a buckle on the opposite side (image 2).

The reduction technique varies depending upon the deformity. The reduction maneuver should reverse the mechanism of injury including angulation, displacement, and rotation as follows [5]:

●For an apex-volar deformity, slightly pronate the wrist while applying direct pressure over the fracture site

●For an apex-dorsal deformity, slightly supinate the wrist while applying direct pressure over the fracture site

●After reduction, obtain plain radiographs to confirm adequate fracture alignment

Observational studies have shown good healing without completion of the greenstick fracture [11,12]; thus, our approach is to reduce greenstick fractures without intentionally completing them.

Once reduced, the arm should be immobilized in a sugar tong and long arm splint (figure 1 and figure 2) or short arm cast with three-point molding to hold the reduction in place (figure 6) [13]. (See 'Splinting' below and 'Casting' below.)

Salter I or II fracture reduction — Salter I fractures have a fracture line through the physis (growth plate) while Salter II fractures have a fracture through the physis that extends through the metaphysis as well (figure 3 and image 3).

These fractures are reduced as follows:

●An assistant can grasp the proximal forearm to maintain longitudinal traction. Alternatively, if an assistant is not available, longitudinal traction can be achieved by suspending the extremity in finger traps with the elbow at 90 degrees prior to and during the reduction (figure 4).

●Provide gentle, direct pressure over the fracture site (figure 7). A snapping sensation usually does not occur because of the smooth cartilaginous surfaces (image 3 and image 9).

●Maintain the reduction with a sugar tong splint or short arm cast. (See 'Splinting' below and 'Casting' below.)

●Obtain plain radiographs to confirm adequate fracture reduction.

The intact periosteum holds the reduction in place, and remodeling typically repairs any minor deformity. Follow-up with an orthopedic surgeon should occur within one week of the initial reduction to ensure that no loss of reduction has occurred while there is still time to intervene without damaging the growth plate.

IMMOBILIZATION — Once the fracture is reduced, the clinician may choose to immobilize the arm using a splint or a cast.

Splinting — Splinting of reduced distal forearm fractures varies by the type of fracture:

●Salter I or II fractures – Sugar tong splint (figure 1). (See "Basic techniques for splinting of musculoskeletal injuries", section on 'Sugar tong splints'.)

●Greenstick or complete fractures – Sugar tong alone or combined sugar tong and long arm splint (figure 1 and figure 2). For this splinting combination, the sugar tong splint should be placed first and then the long arm splint applied. (See "Basic techniques for splinting of musculoskeletal injuries", section on 'Sugar tong splints' and "Basic techniques for splinting of musculoskeletal injuries", section on 'Long arm splint'.)

If a splint is applied, the patient is typically referred for cast application by an orthopedic surgeon within two to five days. This approach allows time for the swelling to go down before the cast is placed but may risk loss of reduction.

Casting — An overview of casting is provided separately. (See "General principles of definitive fracture management", section on 'Casting'.)

Key aspects for casting distal forearm fractures are as follows:

●Materials – The layers of the cast consist of stockinette next to the skin, cotton padding (eg, two inch Webril) that is rolled with one half inch overlap, and two inch fiberglass or plaster casting material. Extra padding should be applied to common pressure points at the wrist (and elbow if a long arm cast is going to be placed). In a long cast, the antecubital area should have only one to two layers of Webril, with extra strips placed over the back of the elbow. Short strips of folded Webril can be placed around the thumb, and at the proximal and distal ends of the cast for extra padding. It is important to ensure no major wrinkles exist in the stockinette and the padding before casting material is applied.

●Molding – Three-point molding of the forearm portion of the cast maintains the fracture reduction and allows the clinician to mold the cast without causing pressure points. The palm of one hand pushes gently distal to the fracture on the side of the intact periosteum, while the palm of the other hand pushes gently proximal to the fracture on the opposite side of the arm. When molding a cast, recreate the force in the direction that was used to reduce the fracture. An assistant's hand is placed more proximally on the arm (below the elbow) on the same side as the most distal hand (figure 8). Once completed, the cast should be wider in the AP diameter than in the lateral diameter (lateral to AP diameter ratio 0.7) and the ulnar border should be straight [1].

●Forearm position in the cast – The cast should be in neutral position with respect to supination and pronation of the hand. Although some orthopedists prefer the wrist to be casted in slight flexion with ulnar deviation to counteract opposing muscles, an observational study of 109 children with distal forearm fractures concluded that the position of immobilization (neutral, pronation, or supination) does not appear to affect maintenance of fracture reduction and residual angulation [14].

●Cast length – When casting a distal forearm fractures, we suggest a short arm cast (picture 1) rather than a long arm cast. A long arm cast may be used for children in whom the forearm is too short to hold a supportive cast (eg, infants and young children) or in children who remove their short arm cast. After a fracture reduction, if a long arm cast is going to be placed, the elbow should be placed at 90 degrees before any casting material is applied; if it is flexed after material is applied, it causes bunching and irritation at the elbow. Typically, a second person is needed to hold the arm (by the fingers) in the proper position.

In a meta-analysis of eight trials comparing management with short arm versus long arm casts in 994 children <16 years old, patients managed with short arm casts less frequently had loss of fracture reduction (22 versus 29 percent); however, the difference was not statistically significant (RR 0.74, 95% CI 0.49-1.13) [15]. There were also no significant differences between the groups in the need for repeat manipulation or cast-related complications. Several of the trials in the meta-analysis had important limitations, including small sample size and lack of blinding. Individual randomized trials included in this meta-analysis also found that children with short arm casts had greater comfort [16], significantly fewer school days missed [17,18], less need for help with daily activities [16,17,19], and greater elbow mobility after cast removal [17].

●Cast splitting – If a large amount of swelling is expected (eg, reduced complete or greenstick fracture), the cast is allowed to set and then is split on both sides with a cast saw (figure 9). It is then wrapped with an elastic wrap (eg, Ace wrap). This procedure avoids neurovascular complications related to arm swelling. The clinician should provide a sling to support the cast.

●Post-casting neurovascular assessment – The patient should have good perfusion of the fingers and be able to fully extend his or her fingers and thumb actively and passively after casting [20]. Poor perfusion, pain on finger extension, or limitation of finger or thumb motion suggests tendon and/or muscle entrapment or a tight cast.

●Assessment of reduction and casting – After closed reduction and casting, post-reduction radiographs are obtained in the radiology department or at the bedside using fluoroscopy [21]. Bedside fluoroscopy has the advantage of timeliness, continued ability to monitor the patient after sedation, and lower radiation exposure.

DISCHARGE AND FOLLOW-UP — Once adequate fracture alignment and immobilization is documented radiographically, the child is fully recovered from sedation, and cast instructions have been provided, the child may be discharged home. (See 'Information for patients' below.)

Timing for orthopedic follow-up depends upon the method of immobilization and the type of fracture:

●If a splint is applied, the patient should be referred for cast application by an orthopedic surgeon within two to five days regardless of the fracture type.

●Patients with casted Salter I or II and greenstick fractures may be referred for orthopedic evaluation in one week.

●Children with casted complete fractures warrant close follow-up to monitor for displacement and should be seen within one week.

Home analgesia, duration of immobilization, and timing for return to full activity are discussed in detail separately. (See "Distal forearm fractures in children: Initial management", section on 'Home care'.)

COMPLICATIONS — Potential complications of distal forearm fractures are discussed separately. (See "Distal forearm fractures in children: Initial management", section on 'Complications'.)

Cast immobilization can be associated with the following adverse events [22]:

●Joint stiffness

●Muscle atrophy

●Tight cast due to tissue swelling with resulting pain, compression neuropathy, vascular compromise, and/or acute compartment syndrome

●Skin breakdown and ulceration due to inadequate padding or the use of a coat hanger or other object by the patient to scratch itchy areas under the cast

●Skin burns during cast setting (more common with plaster casts)

Caregivers should be aware of these potential problems and should be instructed to return for urgent evaluation if the following signs or symptoms are present:

●Severe pain that is not controlled by oral analgesia, ice application to the cast, and extremity elevation

●Inability to move the fingers

●Cold or blue fingers

●Complaint of numbness or tingling

Although possible, splint immobilization is less likely to result in neurovascular compromise or acute compartment syndrome. Pressure necrosis from inadequate padding is still frequent as is loss of reduction if timely follow-up for casting is not assured.

ADDITIONAL INFORMATION — Several UpToDate topics provide additional information about fractures, including the physiology of fracture healing, how to describe radiographs of fractures to consultants, acute and definitive fracture care (including how to make a cast), and the complications associated with fractures. These topics can be accessed using the links below:

●(See "General principles of fracture management: Bone healing and fracture description".)

●(See "General principles of fracture management: Fracture patterns and description in children".)

●(See "General principles of acute fracture management".)

●(See "General principles of definitive fracture management".)

●(See "General principles of fracture management: Early and late complications".)

SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: General management of pediatric fractures" and "Society guideline links: Upper extremity, thoracic, and facial fractures in children" and "Society guideline links: Acute pain management".)

INFORMATION FOR PATIENTS — UpToDate offers two types of patient education materials, "The Basics" and "Beyond the Basics." The Basics patient education pieces are written in plain language, at the 5^th to 6^th grade reading level, and they answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials. Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are written at the 10^th to 12^th grade reading level and are best for patients who want in-depth information and are comfortable with some medical jargon.

Here are the patient education articles that are relevant to this topic. We encourage you to print or e-mail these topics to your patients. (You can also locate patient education articles on a variety of subjects by searching on "patient info" and the keyword(s) of interest.)

●Basics topic (see "Patient education: How to care for your child's cast (The Basics)")

●Beyond the Basics topic (see "Patient education: Cast and splint care (Beyond the Basics)")

SUMMARY AND RECOMMENDATIONS

●Indications – Closed reduction and immobilization should be performed only by properly trained and experienced clinicians. Reduction and immobilization are necessary for significantly displaced or severely angulated closed distal forearm fractures, including displaced complete (image 1 and image 7), greenstick (image 2), and Salter Harris I or II fractures (image 3). When questions about the need for reduction arise in children with distal forearm fractures, discussion with an orthopedic surgeon with pediatric expertise is warranted. (See 'Indications' above.)

●Contraindications – Contraindications to casting of distal forearm fractures by clinicians other than an orthopedic surgeon include any injury that warrants urgent evaluation by an orthopedic surgeon, especially those injuries that warrant emergency surgery. (See 'Contraindications' above.)

Examples include:

•Open fractures that require debridement and definitive orthopedic care in the operating room (OR).

•Salter-Harris III, IV, or V physeal (growth plate) distal radius or ulna fractures (figure 3 and image 4 and image 5) require reduction by an orthopedist with pediatric expertise.

•Distal forearm fractures complicated by joint dislocation (wrist or elbow) or supracondylar fracture also warrant prompt involvement of an orthopedic surgeon and frequently require closed or open reduction in the operating room.

●Preparation – The clinician should ensure that caregivers have a full understanding of the risks of fracture reduction including (see 'Informed consent' above):

•Adverse effects of procedural sedation

•Potential loss of reduction despite appropriate care with the potential need for open reduction and fixation in the operating room

•Potential for cosmetic or functional adverse outcomes, such as:

-Growth arrest with Salter-Harris I or II fractures,

-Refracture with greenstick or complete fractures,

-Loss of wrist rotation with complete fractures).

The clinician should ensure that a careful neurovascular examination precedes attempts at closed reduction.

Procedural sedation provides appropriate analgesia for pediatric forearm fracture reductions and may be augmented by a hematoma or regional intravenous block. (See 'Sedation and analgesia' above.)

●Techniques – The equipment and techniques for closed reduction of distal forearm fractures for specific types of fracture are described in detail in the text. Portable fluoroscopy is useful to check the adequacy of reduction during the procedure. Once the fracture is reduced and immobilized, plain radiographs should be obtained to confirm adequate reduction. (See 'Techniques' above.)

●Splinting – Once the fracture is reduced, the clinician may choose to immobilize the arm using a splint or a cast. Splinting of reduced distal forearm fractures varies by the type of fracture (see 'Splinting' above):

•Salter I or II fractures – Sugar tong splint (figure 1).

•Greenstick or complete fractures – Sugar tong alone or combined sugar tong and long arm splint (figure 1 and figure 2). For this splinting combination, the sugar tong splint should be placed first and then the long arm splint applied.

●Casting – When using a cast for immobilization of distal forearm fractures, we suggest a short arm cast (picture 1) rather than a long arm cast. (Grade 2C). A long arm cast may be appropriate for children in whom the forearm is too short to hold a supportive cast or permits the child to easily remove a short arm cast (eg, infants and young children). (See 'Casting' above.)

For proper cast application, it is important for the clinician to do the following:

•If placing a long arm cast, place elbow at 90 degrees before applying any cast material and limit extremity movement during casting.

•Protect the skin with stockinette as the first layer and cover with adequate amounts of padding.

•Use extra padding over bony prominences.

•Cast the forearm in neutral position with respect to supination and pronation of the hand.

•Ensure three point molding such that the lateral to AP diameter on radiograph is 0.7 (figure 6 and figure 8).

•In patients in whom significant swelling is anticipated (eg, complete fractures, greenstick fractures), longitudinally split the cast on the dorsal and ventral surfaces (figure 9) and apply an elastic wrap to help prevent the development of a tight cast secondary to tissue swelling.

•Ensure good perfusion and active and passive mobility of the fingers and thumb after casting.

●Follow-up – Timing for orthopedic follow-up depends upon the method of immobilization and the type of fracture. (See 'Discharge and follow-up' above.)

●Complications – Casting has a number of potential complications, including pressure sores, neurovascular compromise, acute compartment syndrome, and disuse atrophy. Thus, any child in a cast who appears to be in severe pain, is unable to move the fingers, has cold or blue fingers or complains of burning, tingling, or numbness should be evaluated immediately. (See 'Complications' above and 'Information for patients' above.)