Foundations of Splinting*

Brenda M. Coppard, PhD, OTR/L

Definition of a Splint

Mosby’s Medical, Nursing, and Allied Health Dictionary (2002) defines a splint as “an orthopedic device for immobilization, restraint, or support of any part of the body” (p. 1618). The text also defines orthosis as “a force system designed to control, correct, or compensate for a bone deformity, deforming forces, or forces absent from the body” (p. 1237).

Today, these health care field terms are often used synonymously. Technically, the term splint refers to a temporary device that is part of a treatment program, whereas the term orthosis refers to a permanent device to replace or substitute for loss of muscle function.

Splints and orthoses not only immobilize but also mobilize, position, and protect a joint or specific body part. Splints range in design and fabrication from simple to complex, depending on the goals established for a particular condition.

Historical Synopsis of Splinting

Reports of primitive splints date back to ancient Egypt [Fess 2002]. Decades ago, blacksmiths and carpenters constructed the first splints. Materials used to make the splints were limited to cloth, wood, leather, and metal [War Department 1944]. Hand splinting became an important aspect of physical rehabilitation during World War II. Survival rates of injured troops dramatically increased because of medical, pharmacologic (e.g., the use of penicillin), and technological advances. During this period, occupational and physical therapists collaborated with orthotic technicians and physicians to provide splints to clients: “Sterling Bunnell, MD, was designated to organize and to oversee hand services at nine army hospitals in the United States” [Rossi 1987, p. 53]. In the mid 1940s, under the guidance of Dr. Bunnell many splints were made and sold commercially. During the 1950s, many children and adults needed splints to assist them in carrying out activities of daily living secondary to poliomyelitis [Rossi 1987]. During this time, orthotists made splints from high-temperature plastics. With the advent of low-temperature thermoplastics in the 1960s, hand splinting became a common practice in clinics.

Today, some therapists and clinics specialize in hand therapy. Hand therapy evolved from a group of therapists in the 1970s who were interested in researching and rehabilitating clients with hand injuries [Daus 1998]. In 1977, this group of therapy specialists established the American Society for Hand Therapy (ASHT). In 1991, the first certification examination in hand therapy was given. Those therapists who pass the certification examination are credentialed as certified hand therapists (CHTs).

Specialized organizations (e.g., American Society for Surgery of the Hand and ASHT) influence the practice, research, and education of upper extremity splinting [Fess et al. 2005]. For example, the ASHT Splint Classification System offered a uniform nomenclature in the area of splinting [Bailey et al. 1992].

Splintmakers

A variety of health care professionals design and fabricate splints. Occupational therapists (OTs) constitute a large population of health care providers whose services include splint design and fabrication. Certified occupational therapy assistants (COTAs) also provide splint services. Along with OTs and COTAs, physical therapists (PTs) specializing in hand rehabilitation often fabricate splints for their clients who have hand injuries. PTs are frequently involved in providing splints for the lower extremities. In addition, certified orthotists (COs) are trained and skilled in the design, construction, and fitting of braces and orthoses prescribed by physicians. Dentists frequently fabricate orthoses to address selective dental problems. Occasionally, nurses who have had special training fabricate splints.

Splint design must be based on scientific principles. A given diagnosis does not specify the splint the clinician will make. Splint fabrication often requires creative problem solving. Such factors as a client’s occupational needs and interests influence a splint design, even among clients who have common diagnoses. Health care professionals who make splints must allow themselves to be creative and take calculated risks. Splintmaking requires practice for the clinician to be at ease with the design and fabrication process. Students or therapists beginning to design and fabricate splints should be aware of personal expectations and realize that their skills will likely evolve with practice. Therapists with experience in splinting tend to be more efficient with time and materials than novice students and therapists.

Occupational Therapy Theories, Models, and Frame-of-Reference Approaches for Splinting

The OTPF outlines the occupational therapy process of evaluation and intervention and highlights the emphasis on the use of occupation [AOTA 2002]. Performance areas of occupation as specified in the framework include the following: activities of daily living (ADL), instrumental activities of daily living (IADL), education, work, play, leisure, and social participation. Performance areas of occupation place demands on a person’s performance skills (i.e., motor skills, process skills, and communication/interaction skills). Therapists must consider the influence of performance patterns on occupation. Such patterns include habits, routines, and roles. Contexts affect occupational participation. Contexts include cultural, physical, social, personal, spiritual, temporal, and virtual dimensions. The engagement in an occupation involves activity demands placed on the individual. Activity demands include objects used and their properties, space demands, social demands, sequencing and timing, and required actions, body functions, and body structures. Client factors relate to a person’s body functions and body structures.Table 1-1 provides examples of how the framework assists one in thinking about splint provision to a client.

The practice of occupational therapy is guided by conceptual systems [Pedretti 1996]. One such conceptual system is the Occupational Performance Model, which consists of performance areas, components, and contexts. A therapist using the Occupational Performance Model may influence a client’s performance area or component while considering the context in which the person must operate. The therapist is guided by several treatment approaches in providing assessment and treatment. The therapist may use the biomechanical, sensorimotor, and rehabilitative approaches. The biomechanical approach uses biomechanical principles of kinetics and forces acting on the body. Sensorimotor approaches are used to inhibit or facilitate normal motor responses in persons whose central nervous systems have been damaged. The rehabilitation approach focuses on abilities rather than disabilities and facilitates returning persons to maximal function using their capabilities [Pedretti 1996]. (See Self-Quiz 1-1.)

Each approach can incorporate splinting as a treatment intervention, depending on the rationale for splint provision. For example, if a person wears a tenodesis splint to recreate grasp and release to maximize function in activities of daily living, the therapist is using the rehabilitation approach [Hill and Presperin 1986]. If the therapist is using the biomechanical approach, a dynamic (mobilization) hand splint may be chosen to apply kinetic forces to the person’s body. If the therapist chooses a sensorimotor approach, an antispasticity splint may be used to inhibit or reduce tone.

Pierce’s notions [Pierce 2003] of contextual and subjective dimensions of occupation are powerful concepts for therapists who appropriately incorporate splinting into a client’s care plan. Understanding how a splint affects a client’s occupational engagement and participation are salient in terms of meeting the client’s needs and goals, which may result in an increased probability of compliance. Contextual dimensions include spatial, temporal, and sociocultural contexts [Pierce 2003]. Subjective dimensions include restoration, pleasure, and productivity.Box 1-1 explicates both contextual and subjective dimensions of occupation. In Chapter 3, Pierce’s framework is used to structure questions for a client interview.

Splint Categorization

According to the ASHT [1992], there are six splint classification divisions: (1) identification of articular or nonarticular, (2) location, (3) direction, (4) purpose, (5) type, and (6) total number of joints (Figure 1-1).

Splint Designs

In the past, splints were categorized as static or dynamic. This classification system has its problems and controversies. However, in some clinics ASHT splint terminology is not often used. Therefore, therapists must be familiar with the ASHT classification system as well as other commonly used nomenclature. Static splints have no movable parts [Cailliet 1994]. In addition, static splints place tissues in a stress-free position to enhance healing and to minimize friction [Schultz-Johnson 1996]. Dynamic splints have one or more movable parts [Malick 1982] and are synonymous with splints that employ elastics, springs, and wire, as well as with multipart splints.

The purpose of a splint as a therapeutic intervention assists the therapist in determining its design. Splinting design classifications include (1) static, (2) serial static, (3) dropout, (4) dynamic, and (5) static-progressive [Schultz-Johnson 1996].

A static splint (Figure 1-3) can maintain a position to hold anatomical structures at the end of available range of motion, thus exerting a mobilizing effect on a joint [Schultz-Johnson 1996]. For example, a therapist fabricates a splint to position the wrist in maximum tolerated extension to increase extension of a stiff wrist. Because the splint positions the shortened wrist flexors at maximum length and holds them there, the tissue remodels in a lengthened form [Schultz-Johnson 1996].

Serial static splinting (Figure 1-4) requires the remolding of a static splint. The serial static splint holds the joint or series of joints at the limit of tolerable range, thus promoting tissue remodeling. As the tissue remodels, the joint gains range and the clinician remolds the splint to once again place the joint at end range comfortably. Schultz-Johnson [1996] pointed out that circumferential splints that are nonremovable require no cooperation from those who wear them, except to leave them on.

A dropout splint (Figure 1-5) allows motion in one direction while blocking motion in another [ASHT 1992]. This type of splint may help a person regain lost range of motion while preventing poor posture. For example, a splint may be designed to enhance wrist extension while blocking wrist flexion [Schultz-Johnson 1996].

Elastic tension dynamic (mobilization) splints (Figure 1-6) have self-adjusting or elastic components, which may include wire, rubber bands, or springs [Fess and Philips 1987]. A splint that applies an elastic tension force to straighten an index finger PIP flexion contracture exemplifies an elastic tension/traction dynamic (mobilization) splint.

Static progressive splints (Figure 1-7) are types of dynamic (mobilization) splints. They incorporate the use of inelastic components such as hook-and-loop tapes, outrigger line, progressive hinges, turnbuckles, and screws. The splint design incorporates the use of inelastic components to allow the client to adjust the line of tension so as to prevent overstressing of tissue [Schultz-Johnson 1995]. Chapter 11 more thoroughly addresses mobilization and torque transmission (dynamic) splints.

Many possibilities exist for splint design and fabrication. A therapist’s creativity and skills are necessary for determining the best splint design. Therapists must stay updated on splinting techniques and materials, which change rapidly. Reading professional literature and manufacturers’ technical information helps therapists maintain knowledge about materials and techniques. A personal collection of reference books is also beneficial, and continuing-education courses provide ongoing updates on the latest theories and techniques.

Evidence-Based Practice and Splinting

Calls for evidence-based practice have stemmed from medicine but have affected all of health care delivery, including splinting [Jansen 2002]. Sackett and colleagues [1996, pp. 71-72] defined evidence-based practice as “the conscientious, explicit, and judicious use of current best evidence in making decisions about the care of individual clients. The practice of evidence-based medicine means integrating individual clinical expertise with the best available external clinical evidence from systematic research.”

The aim of applying evidence-based practice is to “ensure that the interventions used are the most effective and the safest options” [Taylor 1997, p. 470]. Essentially, therapists apply the research process during practice. This includes (1) formulating a clear question based on a client’s problem, (2) searching the literature for pertinent research articles, (3) critically appraising the evidence for its validity and usefulness, and (4) implementing useful findings to the client case. Evidence-based practice is not about finding articles to support what a therapist does. Rather, it is reviewing a body of literature to guide the therapist in selecting the most appropriate assessment or treatment for an individual client.

Sackett et al. [1996] and Law [2002] outlined several myths of evidence-based practice and described the reality of each myth (Table 1-2). A misconception exists that evidence-based practice is impossible to practice or that it already exists. Although we know that keeping current on all health care literature is impossible, few practitioners consistently review research findings related to their specific practice. Instead, many practitioners rely on their training or clinical experience to guide clinical decision making. Novel clinical situations present a need for evidence-based practice.

Some argue that evidence-based practice leads to a “cookie cutter” approach to clinical care. Evidence-based practice involves a critical appraisal of relevant research findings. It is not a top-down approach. Rather, it adopts a bottom-up approach that integrates external evidence with one’s clinical experience and client choice. After reviewing the findings, practitioners must use clinical judgment to determine if, why, and how they will apply findings to an individual client case. Thus, evidence-based practice is not a one-size-fits-all approach because all client cases are different.

Evidence-based practice is not intended to be a mechanism whereby all clinical decisions must be backed by a random controlled trial. Rather, the intent is to address efficacy and safety using the best current evidence to guide intervention for a client in the safest way possible. It is important to realize that efficacy and safety do not always result in a cost decrease.

Important to evidence-based practice is the ability of practitioners to appraise the quality of the evidence available. A hierarchy of evidence is based on the certainty of causation and the need to control bias.Table 1-3 [Lloyd-Smith 1997] shows this hierarchy. The highest quality (gold standard) of evidence is the meta-analysis of randomized controlled studies. Next in the hierarchy is one study employing an individual random controlled trial. A well-designed nonrandomized study is next in the hierarchy, followed by quasi-experimental designs and nonexperimental descriptive studies. Last in the hierarchy is expert practitioner opinion.Box 1-2 presents a list of appraisal questions used to evaluate quantitative and qualitative research results.

Throughout this book, the authors made an explicit effort to present the research relevant to each chapter topic. Note that the evidence is limited to the timing of this publication. Students and practitioners should review literature to determine applicability of contemporary publications. The Cochrane Library, CINAHL (Cumulative Index of Nursing and Allied Health Literature), MEDLINE, EMBASE (comprehensive pharmacological and biomedical database), OT Index, HAPI (Health and Psychosocial Instruments), ASSIA (Applied Social Sciences Index of Abstracts), and HealthStar are useful databases to access during searches for research.

References