Short Arm Splinting

Short arm splinting is most commonly used for initial support of the injured extremity (whether surgery is planned or not) and for postoperative immobilization of internally fixed fractures. There are several different types of short arm splints. Each lends itself to a specific subset of orthopedic injuries and issues.

Several indications exist for short arm splinting. This technique can be used to immobilize joints of the hand and wrist or to protect bony and soft tissues in the forearm.

Short arm splints are often used as a means of temporary or preoperative support for a variety of injuries. Bony, ligamentous, or severe soft-tissue injuries to the hand located at the base of the fingers (proximal phalanx) or above (proximal) are adequately immobilized by short arm splints.

Any injuries to the fourth or fifth proximal phalanges, the metacarpals, ^{[1, 2]} the ulnar side of the wrist, or the distal ulna are amenable to an ulnar gutter splint, a specific type of short arm splint. A functional metacarpal splint may be an acceptable alternative for stable fifth-metacarpal fractures.

Injuries to the second and third proximal phalanges, the metacarpals, or the distal radius may be held with a radial gutter splint. ^[3]  Although distal radius fractures (DRFs) are commonly immobilized in sugar-tong splints, Bong et al showed that radial gutter splints were equally efficacious in maintaining the initial reduction and were better tolerated by patients. ^[4]  There remains debate regarding the optimal method of immobilization for DRFs. ^[5]

Thumb spica splinting can be used to provide temporary stabilization of scaphoid fractures and a variety of bony and ligamentous injuries to the thumb and first metacarpal. It may be used for postoperative stabilization after repair of the ulnar collateral ligament of the thumb. ^{[6, 7]}

Volar and dorsal slab splints (anterior-posterior splints) covering the palmar/dorsal aspect of the metacarpals, the wrist, and the distal forearm are useful for protecting soft-tissue injuries, some carpal bone fractures (excluding scaphoid), and childhood buckle fractures. They have been used for DRFs but do not appear to have any advantages over sugar-tong splints in this setting. ^[8]

Although short arm splints are less frequently used for definitive treatment, there is some support in the literature for long-term use. Short arm support with a removable prefabricated splint has been shown to be as effective as casting in the treatment of pediatric buckle and minimally displaced DRFs while resulting in less complications and higher patient satisfaction. ^{[9, 10, 11]} Short arm splinting has even been suggested for use in minimally displaced adult DRFs. ^[12] Adult ulna fractures that are minimally displaced may be treated in a functional brace. Prefabricated wrist splints are often used in the treatment of carpal tunnel syndrome (CTS).

For fractures and ligamentous injuries that are accompanied by open wounds or burns, a splint may be used instead of a cast for definitive treatment. The splint allows easier access to the superficial tissues while still treating the bony or ligamentous injury. Removable wrist splints may also be used as the definitive treatment for mild CTS and sprains of the wrist.

Short arm splints are also placed after the completion of definitive surgical fixation in order to protect the surgical site. ^{[13, 14]} For the most part, these postoperative indications are dependent on the surgeon’s preference. They tend to mimic the indications for preoperative and temporary fixation (eg, a thumb spica splint after thumb/first metacarpal surgery or a volar slab splint after carpal tunnel release). These postoperative splints are used to protect the incision, as well as to temporarily immobilize the recently repaired anatomy.

In a randomized clinical study of 30 patients who underwent surgical repair of skier's thumb, the use of a modified spica splint that allowed immediate postoperative motion led to enhanced patient function and a shorter time to functional recovery as compared with the use of a standard spica splint. ^[15]

In a randomized controlled trial that included 256 patients with hand and wrist soft-tissue injuries, the treatment efficacy of standard-sized short arm splints (n = 117) was compared with that of half-length short arm splints (n = 139). ^[16]  The two groups were not found to differ significantly with respect to either swelling or pain score after 1, 2, and 3 weeks.

Contraindications for short arm splinting are relatively sparse. On occasion, the soft-tissue injuries accompanying fractures may be so severe as to make splinting for anything longer than a few hours impractical. These severe soft-tissue injuries would normally necessitate prompt operative intervention.

After some procedures, particularly those involving the microvasculature, splints may interfere with the required monitoring, but a splint can usually be modified so as to allow for this. If frequent wound care is required, a removable splint is generally used.

In cases of decreased ability to feel the skin (neuropathy), both splinting and casting can lead to skin breakdown without the patient realizing. Skin checks are recommended to minimize the chance of such ulceration. Finally, long-term splinting across joints can lead to stiffness and sometimes permanent loss of joint motion, especially in the joints of the hand and fingers.

Best practices

Short arm splints should not be used when prevention of pronation and supination is necessary. In this case, a sugar-tong splint, a long arm splint, or a long arm cast should be considered.

The decision to apply a splint rather than a cast requires several considerations. Although casts provide more support by virtue of their circumferential nature, they can be more difficult to apply. In addition, applying rigid circumferential material in an acute injury setting does not allow for the variations in swelling that may take place.

Thus, casting in the face of an acute injury runs the risk of neurovascular compromise, pressure injury to the skin, and compartment syndrome. Although these conditions are still possible in a splint, especially a poorly applied splint, they are more likely to occur with casting.

In the majority of conditions, splinting should not be a long-term treatment. In the setting of acute injuries, splints are often applied as a means of temporary stabilization either preoperatively or until a cast can be applied. In this case, follow-up should be arranged promptly (usually in less than 2 weeks) both to monitor the splint and to arrange for definitive care.

Earlier follow-up or even constant monitoring on an inpatient basis can be considered for those patients with severe injuries necessitating prompt operative intervention or those patients in whom pain and neurovascular status are difficult to monitor because of preexisting neurologic conditions or inability to communicate.

Although there is some variability in the literature on this issue, full-time splint wear appears to lead to more symptomatic and functional improvement than nighttime wear alone. ^[17]

Procedural planning

The first steps in applying a short arm splint involve preparing the patient. Before any splint application, especially those involving a reduction of a fracture or a joint dislocation, the neurovascular status of the injured extremity must be determined and documented. The arm should be clean and dry, and any open wounds should be irrigated and addressed.

Complication prevention

Most complications of splinting can be avoided by proper splint application. Extremes of flexion or extension are avoided to prevent discomfort and muscle or tendon damage. Proper padding of the splint at all bony prominences can help prevent pain, irritation, thermal burns, and pressure sores. The neurovascular status of the arm is monitored during and after the splinting procedure.

Proper splint application for fractures involves a three-point mold technique. Attention to this detail can prevent loss of reduction in some less stable fractures. Special consideration should be made for any patient in whom it will be difficult to monitor discomfort and neurovascular status after splinting. If a patient is unable to communicate the pain that is felt, careful splint application and prompt follow-up are important to avoid complications.

Prolonged splint immobilization of joints can lead to stiffness and permanent loss of motion, and this issue should be considered in arranging follow-up. Pressure injuries and skin breakdown are common complications of splint usage. These can usually be avoided by proper splint application and patient follow-up. Adequate padding of the splint can dramatically decrease the risk. Any splint that gets dirty or wet should be changed; these conditions increase the risk of skin breakdown and infection.

The most serious complication of splints is the potential for compartment syndrome. This condition is less common in the upper extremity than in the lower extremity, and its incidence is lower when a splint is used rather than a circumferential cast. However, if a splint is applied incorrectly, compartment syndrome can still occur, especially after severe trauma to the forearm.

Several mistakes in splint application can increase the chances of compartment syndrome, including the following:

• Circumferential application of nonstretching cotton gauze over an open wound (blood can cause the cotton to harden and restrict swelling)
• Failure to place the arm in the position of function
• Excessively tight wrapping over the splint

The most important aspect of splint application for avoiding compartment syndrome is careful monitoring of the patient. Any changes in neurovascular status should be considered an urgent indication for splint removal and reexamination. In addition, a splinted arm, especially after reduction of a displaced fracture, should be more comfortable than before. Therefore, increasing pain in a splinted extremity should also be cause for concern.