Studies of IMAK Products

Veteran's Administration Study

Prominent Study Provides the Pil-O-Splint® As Best Treatment For Carpal Tunnel Syndrome

San Diego, CA- The Veterans Administration Healthcare System, San Diego and the University of California, San Diego, Department of Orthopedics released a study in the Journal of Hand Therapy that identified the IMAK Pil-O-Splint the most effective nighttime splint for the treatment of Carpal Tunnel Syndrome.

Medical experts conservatively estimate that as many as 15 million Americans suffer from Carpal Tunnel Syndrome (CTS) and other "Repetitive Stress Injuries". Aside from costly and often risky surgery, many CTS sufferers have had few options for comfortable, workable management of their pain.

Orthopedic practitioners rely upon nighttime splinting as the best practice for non-surgical treatment for Carpal Tunnel Syndrome. In the past, finger positioning was often overlooked when prescribing splints. This current UCSD/VA Study clearly sites that "both wrist and finger positioning should be considered as very important variables in nocturnal splint selection and prescription."*

The study evaluated four different products representative of the types of splints commonly used. All four splints provided some limitations to wrist motion. However, only one splint provided the necessary restriction to finger motion- the Pil-O-Splint.

"We are very proud of these findings. It is exciting to know that our Pil-O-Splint provides proven, non-surgical pain relief for people who suffer from CTS and other Repetitive Stress Disorders," said Aurelia Koby, president of IMAK Products Corporation.

The Pil-O-Splint was invented by Ian MacMorran, M.D., an orthopedic and hand surgeon, to relieve wrist and forearm pain during rest and sleep. "Pil-O-Splint has provided my patients with comfortable and therapeutic relief, and for many, their first pain-free sleep in years. It is an honor to see my personal findings validated in such a important study."

*For the published study, refer to the Journal of Hand Therapy, Volume 15, Number 3, July/September 2002.- Abstract and conclusions listed below.

Comparison of Range of Motion Constraints Provided by Prefabricated Splints Used in the Treatment of Carpal Tunnel Syndrome: A Pilot Study

Eileen Apfel, OTR, CHT
Department of Physical Medicine and Rehabilitation Medicine
Division of Occupational and Hand Therapy
Veterans Administration Healthcare System
San Diego, California

Merry Johnson, MS, OTR
Department of Physical Medicine and Rehabilitation Medicine
Division of Occupational and Hand Therapy
Veterans Administration Healthcare System
San Diego, California

Reid Abrams, MD
Department of Orthopedics
Division of Hand and Microvascular Surgery
University of California and Veterans Administration Healthcare System
San Diego, California

ABSTRACT:

Nocturnal splinting of the wrist is commonly used to treat carpal tunnel syndrome. Rationales for overnight wrist splinting are based on several research studies, which suggest that passively and actively sustained positions of the wrist and digits during sleep contribute to elevated carpal tunnel pressures. The types of splints used for carpal tunnel syndrome include custom and prefabricated orthoses of many variations. The purpose of this paper is to assess the resting and passive range-of-motion position restrictions and parameters provided by four prefabricated orthoses, commonly prescribed for or used by patients at the authors’ treatment facility. A literature review provides information that supports optimal wrist and finger positioning to minimize resting carpal tunnel pressures. This information may be useful in determining the most effective splint design choices.

Debates about the best conservative techniques for the treatment of carpal tunnel syndrome (CTS) continue to appear in the literature. Although many causes and treatments have been described, nocturnal splinting remains a standard component of non-surgical intervention.

We investigated the range-of-motion (ROM) parameters for four prefabricated nocturnal splints commonly used in the treatment of CTS by patients at our facility. Wrist and digit ROM were measured both at rest and passively in all four splints. A literature review provided information about the optimal wrist and finger positioning to minimize resting carpal tunnel pressures, which was considered in analysis of the study results.

LITERATURE REVIEW

Rationales for overnight wrist splinting are based on the findings of several research studies, which suggest that passively and actively sustained positions of the wrist and digits assumed during sleep may contribute to elevated carpal tunnel pressures. Some commonly sustained positions include fetal positions (simultaneous wrist and finger flexion) and combined wrist and finger extension. Other specific positions have not been addressed in the literature.

The types of splints used for CTS include custom and prefabricated orthoses of many variations. Although there is consensus about optimal wrist posture, most authors do not consider the need for proper finger positioning. The literature on CTS contains information about the effects of short-term and prolonged wrist and finger positioning.

Carpal tunnel pressure has been shown to be elevated in patients with CTS and is considered an important factor in the development of the syndrome. Much research has been performed in attempts to understand the effects of specific hand positions on carpal tunnel pressure. “Carpal tunnel pressure has a parabolic relationship with the position of the wrist: It increases with greater deviation from neutral.” This is true both for patients with CTS and for controls. In a number of experimental studies, extreme wrist posture has been shown to increase carpal tunnel pressure and to be associated with the development of CTS.

Strong evidence shows that finger postures can contribute to elevated carpal tunnel pressures because of movement of the origin of the lumbrical muscle bellies into the carpal canal.

Cobb et al. performed a series of cadaveric experiments in which they maintained the wrist cadaver in neutral position and varied the positions of the fingers from full extension to a full fist. One group of cadavers had intact lumbricals, and one group had the lumbricals removed. A pressure transducer measured pressure in the carpal canal as the cadavers were placed in each of the four positions—100% finger flexion (a tight fist), 75% finger flexion (such that tips of the fingers were brought to the level of the thumb web space), 50% finger flexion (such that the distal tips of the fingers are even with the distal aspect of the palm), and full extension of digits (no finger flexion). The study reported that:

A progressive increase in carpal tunnel pressure was noted for each degree of finger flexion in the study group with intact lumbricals. The pressure increase for the five cadaver specimens with intact lumbricals were linear with a greater amount of change in pressure (increased pressure) noted between 75% and 100% finger flexion positions. In contrast, when the lumbricals were removed from the cadavers, the mean change in carpal tunnel pressure was relatively minimal.

RESULTS

All wrist ROM measurements are reported here as extension/flexion, in degrees, without plus or minus value modifiers. In the tables, wrist flexion measurements are listed as negative numbers, and extension measurements have no plus or minus values assigned. Digital ROM parameters are listed as percentages of a full fist (Tables 1 to 4).

Range of Motion of the Wrist Without Splints

Initial testing was done to determine baseline PROM parameters of the three cadaver wrists and digits without splints, prior to any experimentation (Table 1). Wrist PROM was evaluated first with the digits free (allowed to move with natural tenodesis), then with combined maximal passive extension of the wrist and digits (Figure 2). Finally, the digits were placed in maximal passive flexion combined with passive wrist flexion (Figure 3). These two combination positions (Figures 2 and 3) are referred to on Tables 1 to 4 as "with composite digits."

Baseline/End Passive Range of Motion of the Wrist

With no splint and "with composite digits," wrist PROM was greatest in the small cadaver at 75° /75° less in the large cadaver at 65° /60°, and least in the medium cadaver at 60° /55°. Extension /flexion averaged 70° /63° and total passive motion (TPM) 133°. At the end of all testing, PROM with composite digits was unchanged.

With the "digits free," wrist PROM measurements were 75° /75° for the small and large cadavers and 60° /60° for the medium cadaver. The average wrist PROM for the three cadavers (with digits free) was 70° /70° (140° TPM).

Passive Range of Motion of the Wrist with Splints

All wrist PROM measurements are reported in Table 2. They all include composite finger extension and flexion measurements as described previously. Flexion measurements are reported with negative signs (minus modifiers) in the tables. They are reported here in the text as extension/flexion, in degrees, without plus or minus value modifiers.

EZY Wrap Splint. Wrist PROM was 50° /10° (TPM 60°) in the small cadaver, 40° /15° (55° TPM) in the large cadaver, and 30° /10° (40° TPM) in the medium cadaver. The average wrist PROM with the EZ Wrap splint was 40° /12° (52° TPM with composite digits).

Futuro Wrist Splint. Wrist PROM was 65° /35° (100° TPM) in small cadaver, 55° /40° (95° TPM) in the large cadaver, and 50° /30° (80° TPM) in the medium cadaver. The average wrist PROM with the NeoFlex Wrist Splint donned was 57° /35° (92° TPM with composite digits).

Pil-O-Splint. Wrist PROM was 10° /10° (20° TPM) in the small cadaver, 5° /15° (also 20° TPM) in the large cadaver, and 0° /10° (10° TPM) in the medium. The average wrist PROM with the Pil-O-Splint donned was 5° /12° (17° TPM with composite digits).

Resting Position of the Wrist with Splints

Each cadaver was fit in random order with each of the appropriately sized four splints. The extremities were pronated, supported only by a 3 x 3 x 9-inch block of wood located at the proximal third of the forearm (as described under Methods) (Table 2).

EZ Wrap Splint. The resting wrist position was 10° extension in the large cadaver, 5° flexion in the medium cadaver, and 5° flexion in the small cadaver. The average wrist resting position was 0°, or neutral.

Futuro Wrist Splint. The resting wrist position was 10° extension in the large cadaver, 10° flexion in the medium cadaver, and 5° flexion in the small cadaver. The average wrist resting position was 0°, or neutral.

NeoFlex Wrist Splint. The resting wrist position was 10°flexion in the large cadaver, 15° in the medium cadaver, and 15° in the small cadaver. The average wrist resting position was 13° flexion.

Pil-O-Splint. The resting wrist position was 0° (neutral) in the large cadaver, 10° flexion in the medium cadaver, and 5° flexion in the small cadaver. The average wrist resting position was 5° flexion.

Passive Range of Motion of the Fingers (Percentage of Full Fist) Without Splints

Without splints donned, passive ROM of the fingers was fully unrestricted (0% /100% of full fist), even when combined with passive extension /flexion of the wrist (composite wrist) in all three cadavers (Table 3).

Resting Finger Position (Percentage of Full Fist) Without Splints

Without splints donned, and with the forearms positioned in pronation, with wrists in gravity-assisted flexion, resting finger positions were all the same at full extension or 0% of a full fist (Table 3).

Passive Finger Range of Motion (Percentage of Full Fist) with Splints

With three of the four donned splints, all three cadavers had unrestricted finger motion. The exception was the Pil-O-Splint, which restricted passive motion from 0% to 75% of a full fist (Table 4).