Splint Troubleshooting 101

10 questions to ask yourself when you make that splint

Splinting truly embodies the art and science of occupational therapy. It is very much an acquired skill that requires us to merge form with function. This process allows us to provide an aesthetically pleasing orthosis that either mobilizes, immobilizes, protects or assists in improving function of the upper extremity.

The evolution of splinting has taken us from D-rings to Velcro™; and towering outriggers to the more contemporary low-profile outriggers. Advances in surgery as well as newer, more efficient splint materials are changing the way that we, both novices and seasoned veterans alike, make splints.

It is important to pay attention to each phase of splinting to assure that we are meeting our therapeutic goals. A mistake made during any phase of splinting translates into increased time spent to make adjustments, and more time is a luxury that few of us have. It really does pay to troubleshoot first, rather than asking questions later.

1. Do I have the right grip?

Using too much force during the fabrication phase of splinting results in pressure areas on the patient and fingerprints on the splint. Conversely, applying too little force while molding the splint may result in a loose-fitting splint that is likely to migrate and cause friction on the skin. Splint material with increased drape generally requires less forceful contact by the therapist’s hands, while material with increased rigidity requires a more even amount of pressure.

Some splint materials also have a coating that is slightly tacky when heated and will stick to the patient during the fabrication process, requiring less pressure by the therapist. This can be helpful for splints that need to be molded at multiple areas at the same time, or are placed on a body part in the against-gravity position. This may be a concern while fabricating elbow splints or forearm splints when either supination or pronation is restricted.

2. To pad or not to pad?

There are a lot of opinions about padding, but therapists generally agree on one
issue–avoid padding as an afterthought. Padding a spot on the splint that is already too tight will only serve to diminish the already-sparse interface between orthosis and patient, making it even tighter.

It is best to identify “hot spots” where pressure is likely to arise—such as the ulnar styloid/head of the ulna at the wrist or the dorsal MCP (metacarpophalangeal) joints—and pad during the fabrication phase. The same technique applies for patients who demonstrate point tenderness at arthritic joints, incisions, sites of injury or tendonitis.

Padding can be applied ahead by using closed-cell/waterproof padding that can be applied to the splint before dipping in the heat pan; or open-cell padding which can be placed padding-side down on the patient with stockinette over it to keep it in place before the splint is molded onto the patient. Once you have molded the splint onto the patient and it has cooled, remove the padding from the patient, remove the backing and apply the padding to the corresponding area in the splint.

3. Have I crossed the minimally acceptable number of joints?

Make sure that the splint provides adequate support and protection of injured structures but also allows for function of non-injured structures. It is important to have a good understanding of not only anatomy, but also the referring physician’s comfort level with your splinting ideas. For example, some physicians will allow a hand-based gauntlet splint, which allows for MCP ROM, to protect a non-displaced fifth metacarpal shaft fracture; others opt for the more conservative approach of bracing the metacarpal and the MCP as well.1

Therapists are required to contact the referring physician for authorization to make any potential changes to the required original splint prescription.

4. What does the patient plan on doing in the splint?

You don’t want to find out the hard way that a short opponens thumb splint fabricated out of 1/8th inch material is not going to fit under a cross-country ski glove. It’s best to work these details out during the planning phase of splinting to make sure that the patient will be able to maximize the protective nature of the splint. It is also imperative to be clear with the patient regarding what activities should not be performed in the splint, such as operating heavy equipment.

5. Have I met the physician’s specifications?

Make sure to have a goniometer nearby. It can be difficult to estimate 20 degrees of wrist flexion, 40 degrees of MCP flexion and 10 degrees of PIP flexion when the physician is expecting to see your dorsal block splint with exactly those measurements.

Also, keep in mind that by using a material without enough rigidity or without providing enough lateral coverage for both dorsal and volar splints, you are likely to cause the material to flex under pressure and those measurements will no longer be accurate.

6. Will this splinting material get the job done?

Choose to stock material that will give you the best of both worlds. Splint material manufacturers are producing therapist-friendly materials that are fingerprint resistant, yet also allow good drape. Make sure you are providing materials that are rigid enough to support a bulky hand and can endure progressive activity for those patients requiring it. Also, you will need thicker material to support larger joints, such as the elbow.

The same rules apply for moving parts on dynamic splints or components that apply force on static-progressive splints. For example, you will need increased tension on the dynamic/static progressive traction used to stretch a joint in order to improve mobility, whereas a finger status-post extensor or flexor tendon repair will likely require less tension on the traction, comparatively. A dynamic flexion Kleinert splint must have traction with sufficient tension as to passively place the affected digit(s) in flexion but also give sufficient recoil as to allow the patient to actively extend the digit(s) within the confines of the splint.

Choosing the correct components allows the splint to provide the necessary 5 millimeters of tendon glide in order to minimize adhesions. It is of critical importance in areas requiring differential glide–zone 2 of the flexor digitorum profundus and flexor digitorum superficialis—and in areas where tendon contact to bone is at it’s closest point than any other place in the body–zone 4 at the extensor tendons.2 Sometimes a plain rubber band just won’t do the trick, but there are other options—fishing line with springs or braided elastic, for example.

Some splint material distributors are even willing to provide a department in-service in order to showcase their new materials. They may provide samples during the in-service so that you can make a few trial mini-splints and see what materials work best for you.

7. Do I know the time and temperature?

Follow the manufacturer’s guidelines for the water temperature and the time required to properly heat the splint material. A droopy, overheated splint coming out of an over-heated pan isn’t going to get much better, without taking some corrective action. Some splint material has memory and will “forgive” you by regaining its original shape upon being placed in a pan readjusted to the correct temperature for the correct amount of time, whereas other materials turn clear after being heated to let you know that they are ready to be removed from the pan. Keep a timer nearby. Make sure to keep a list of splint material heating guidelines as a reminder, especially if you stock a variety of different materials or work with float or per-diem therapists who may be unfamiliar with your stock of splint materials.

8. Does the patient understand the purpose of the splint?

Discuss the reasons for wearing the splint and the wearing schedule during the planning phase to assure that all involved are on the “same page.” Patients may not have been instructed in the details regarding their splints, or may not have understood what their splints would look like prior to arriving at the clinic.

Dynamic outriggers, for example, have the potential to surprise patients with their mechanical appearance. Showing a picture ahead of time may minimize the surprise or any anxiety that the patient may be feeling.

Sometimes the rules of anatomy that guide our splinting practices can leave patients feeling befuddled. Patients are frequently dismayed to leave the hospital post-operatively in a long arm thumb spica splint, which crosses the elbow, wrist and thumb to address a scapholunate ligament reconstruction. To help the patient understand, have some visual anatomic education materials available and demonstrate the dynamic forces that forearm rotation places on the wrist.

9. Have I identified potential problems that may contribute to splint intolerance?

Allergies, insensate skin, diminished sensation or fragile skin are all potential barriers to the patient tolerating the splint. Remind patients with limited or absent sensation to visually inspect their skin regularly for pressure areas so that a readjustment can be performed before skin integrity is compromised. The use of closed-cell padding and new antimicrobial splint materials may be a prudent choice for patients with skin eruptions such as folliculitis. Fragile skin can be protected with generous use of padding during the fabrication phase. Prevent problems such as skin maceration by using ventilated materials that allow air circulation, or by encouraging the use of stockinette to absorb perspiration. As always, remind patients to regularly clean and dry splint materials completely, doing so more frequently during the hot weather months.

10. Is this splint in the optimal position to protect injured/repaired structures and reduce symptoms?

Advances in diagnostic imaging and research have led therapists into the frontier of evidence-based practice, improving our outcomes and increasing our knowledge of functional anatomy. For example, we now use wrist splints placed in neutral—not wrist cock-up splints placed in 30 degrees of wrist extension—in order to treat carpal tunnel syndrome.

Avoid placing excessive tension on healing structures, especially where stability could be affected. Extensor tendon repairs to the digits, in particular, are generally splinted in full extension to avoid the undesirable effects of “lagging”—stretching out or separating a repair site.2

Conversely, it is often advisable to splint the hand in the “safe position” to address simple closed trauma, repetitive trauma or sprains when stability has not been compromised. The “safe position” is 70-90 degrees of MCP flexion and 0-10 degrees of IP flexion, which is useful in providing rest to the affected structures while minimizing any ligamentous shortening that could contribute to an extensor contracture of the MCPs.1 The thumb may be splinted in 30 degrees of abduction or the “hitchhiker position”—full extension—depending on the location and intensity of inflammation and irritability of the injured, but intact, structures.

References

1. Hand Rehabilitation, 1999; Falkenstien F, Weiss-Lessard S

2. Rehabilitation of the Hand, Fifth Edition, Chapter 31; Evans, R