DYNAMIC MP EXTENSION SPLINT FABRICATION USING THE

PHOENIX OUTRIGGER PATENTED

The PHOENIX OUTRIGGER package includes: dorsal and radial wire supports; four 3" pre-tied finger slings three 3" finger slings with grommets; 5/64" hex wrench; four slotted pulleys; one rubber band post (thumb nut). Additional splint supplies needed but not included are: low temperature thermoplastic; strap material, padding, stockinette traction component (rubber band or spring and spring holder) thumb nuts or rivets (see Step#7) Equipment needed includes: splinting pan or other equipment for heating water; heat gun; drill or punch.

FABRICATION OF THE THERMOPLASTIC BASE

1. Prepare a dorsal splint pattern. The hand and forearm are wrapped with gauze or tube stockinette. Additional padding is placed over the distal ulna. Later this padding is placed on the inside of the splint. As the warm thermoplastic is shaped over the forearm and hand, the wrist is positioned at neutral or slight extension. 2. As the palmar bar is shaped, care is taken to maintain the distal transverse arch. The palmar bar should rest proximal to the palmar crease so that full MP flexion is possible. Care is taken not to bond the loose end of the palmar bar to the splint.

ATTACHMENT OF THE PHOENIX OUTRIGGER

3. To mark the location of the outrigger, the splint is placed on the hand. The PHOENIX OUTRIGGER is placed over the dorsum of the splint so that the most distal (curved) point of the transverse wire rests over the mid portion of the proximal phalanx of the middle finger. Then the curve of the transverse wire is aligned over the mid portion of the proximal phalanges of the index, ring, and little fingers. (It is helpful if the outrigger's wire base is heated with a heat gun. Upon contact with the thermoplastic, the wire embeds itself.

4. There are two methods to attach the outrigger:

a) bonding
b) thumbnuts

a) A layer of thermoplastic is bonded over the outrigger's wire base. Rivets may be used to reinforce the bond.

b) Holes are punched or drilled in the thermoplastic. Thumb nuts are securely screwed over the outrigger and through the splint base. If necessary, the metal screws may be heated with the heat gun to countersink them into the thermoplastic.


ATTACH SLINGS AND STRAPS

5. Nylon lines of the finger slings are threaded through each wheel. Then, the nylon line is folded at its thickest part. This will help to center and hold the position of the rubber band or spring. 6. Straps are attached at forearm, wrist, and palmar bar. A traction component (in this photo, a #19 rubber band) is attached to the nylon line of each finger sling. A hole is punched or drilled for the rubber band post. Its location is determined either by estimating or by measuring the traction force. (Spring holders are available.)
ADJUSTMENT OF THE SLOTTED PULLEYS

7. The hex wrench is used to release the set screw of each pulley. The index finger is placed in the fingersling. The rubber band is attached proximally.The pulley is adjusted to achieve the desired angle of pull. Both proximal-distal and radial-ulnar adjustment are possible.

8. Most often, each finger is positioned to rest in extension with no radial or ulnar deviation. (Following implant resection arthroplasties, some therapists choose to remove the extension assist for the little finger and to hold the position of that finger by taping it to the ring finger, often called "buddy splint".

USE OF THE RADIAL OUTRIGGER

9. If the radial outrigger is used, it MUST be attached at the bend in the dorsal wire support. The set screw at the top of the radial outrigger holds its position.To adjust the length of the radial outrigger, the set screw at the side is released. The wire is trimmed to the desired length. Generally, the end of the radial outrigger is opposite the middle of the middle phalanx of the index finger. It may be longer or shorter, depending upon the angle of pull needed. Often it is bent to rest closer to the radial aspect of the index finger. This is for the patient's convenience, since the distance of the attachment does not affect the angle of pull. 10. To achieve a force couple effect for rotation of a digit (as the correction of pronation deformity shown on index finger), two fingerslings are used: one dorsal; one radial. If necessary, dorsal nylon lines may cross over each other. It is recommended that the PIP joints be stabilized with dorsal splints. Additional radial support without the rotating force may be used (as the correction of ulnar deviation shown on the middle finger)