Dynamic traction wrist cast brace

A brace for treatment of distal radius fractures allows an adjustable range of motion while simultaneously providing for distal traction. The brace has hinges with adjustable stops, the hinges being made of radiolucent material to allow x-rays without the necessity of removing the brace. Adjustable tensioners are used to provide distal traction by way of a metacarpal pin placed in slots in hand members. The brace is adjustable for different size patients.

BACKGROUND OF THE INVENTION 
The present invention relates to a wrist cast brace. More specifically, the 
present invention relates to a wrist cast brace which allows for wrist 
motion. 
Intra-articular fractures, or fractures which extend into the joint, 
require anatomic reduction and early mobilization whenever this is 
possible. However, in many circumstances the degree of comminution or bony 
fragmentation precludes the achievement of a satisfactory reduction. Under 
these conditions, joint incongruity may lead to progressive degenerative 
arthritis. 
Early motion has been observed experimentally to provide a stimulus for the 
healing of defects in articular cartilage. Clinically, the use of traction 
and early motion in comminuted intra-articular fractures has been used to 
improve joint congruity and to stimulate fibrocartilage repair of the 
articular cartilage defects. 
The following U.S. patents are illustrative of various splints, braces or 
similar devices: U.S. Pat. Nos. 2,357,323 (Goldberg, Sept. 5, 1944); 
2,767,708 (Keropian, Oct. 23, 1956); 3,327,703 (Gamm, June 27, 1967); 
3,785,371 (Lewis, Jan. 15, 1974); 3,788,307 (Kistner, Jan. 29, 1974); 
4,191,373 (Lancellotti, Mar. 4, 1980); 4,265,230 (Jordon, May 5, 1981); 
and 4,336,796 (Andrews et al, June 29, 1982). 
The Goldberg patent describes a splint with adjustable stops for 
positioning the metacarpals and maintaining a fixed position. More 
specifically, a clamp which is slidable within a slot is used to adjust 
the device depending upon the size of a patient's hand. 
The Keropian patent shows an orthopedic brace for the hand of a patient 
suffering from poliomyelitis. It is adjustable and allows motion through a 
device which is spring-loaded to aid a patient with muscular problems. The 
spring allows flexion and extension of the wrist. The device is strapped 
to the arm. Slots are used to permit sliding of a wrist section of the 
brace relative to a forearm section of the brace. Metallic hinge pins are 
used for adjustment purposes. 
The Gamm patent discloses an elastic support for stabilization of the wrist 
and to simultaneously allow flexing movements of the patient's wrist. 
The Lewis patent shows an elbow sleeve having adjustable hinge limits to 
prevent a wearer from flexing his elbow beyond certain points. 
The Kistner patent discloses a non-mobile wrist splint with adjustable 
positioners. It is intended to hold a wearer's wrist in a fixed position. 
The Lancellotti patent discloses an elbow brace for treating tennis elbow. 
The brace includes a slidable connection to allow movement of a forearm 
section relative to another section. 
The Gordon patent shows a traction splint which places tension upon a 
patient's leg by use of a tether connected to a pin on a splint frame. The 
joints are held in a fixed position. 
The Andrews et al patent shows a distal extremity traction device for the 
femur. It includes a width adjustment feature having a slot and bolt. 
However, it does not allow maximum motion at the affected joint. 
The use of dynamic traction implementing early knee motion has been 
accomplished by [Apley, Apley's System of Orthopaedics and Fractures, 6th 
Ed., London, Butterworth Scientific (1982)] for the treatment of tibial 
plateau fractures. 
The concept of distal traction to avoid shortening of forearm length and 
loss of radiocarpal and radioulnar integrity was developed by [Green, J. 
of Bone and Joint Surgery, 57A:304-310 (1975)] through the use of pins and 
plaster. However, Green's technique did not allow for wrist motion. 
OBJECTS AND SUMMARY OF THE INVENTION 
It is a primary object of the present invention to provide a new and 
improved dynamic traction wrist cast brace. 
A more specific object of the present invention is to provide a wrist cast 
brace allowing a full range of wrist movement simultaneously providing for 
distal traction. 
Another object of the present invention is to provide a wrist cast brace 
which is readily adjustable for different size patients. 
Yet another object of the present invention is to provide a wrist cast 
brace including adjustable tensioners to adjust the amount of tension 
applied to the joint. 
A still further object of the present invention is to provide a wrist cast 
brace wherein x-rays may be taken without removal of the brace. 
A still further object of the present invention is to provide a wrist cast 
brace which is adjustable to allow for different ranges of motion of the 
wrist joint. 
The above and other objects of the present invention which will become 
apparent from the following description are realized by a dynamic traction 
wrist cast brace comprising: first and second forearm frame members 
disposed on opposite sides of a forearm cast; first and second hand frame 
members; first and second hinges respectively pivotably connecting the 
first and second forearm frame members to the first and second hand frame 
members, the first and second hinges operable to allow patient wrist 
motion; a transmetacarpal pin mounted to the first and second hand frame 
members and slidable relative to the first and second hand frame members, 
the transmetacarpal pin operable to cause the first and second hand frame 
members to track movement of a patient's hand; and first and second 
tensioners respectively attached to first and second sides of the 
transmetacarpal pin. The brace further comprises first and second end 
frame members adjustably attached together and adjustably mounted to the 
respective first and second hand frame members such that the width and 
length of the brace can be adjusted to fit a particular patient. The first 
and second end frame members are each adjustably mounted to the respective 
first and second hand frame members by a series of sequential holes. The 
transmetacarpal pin is mounted in first and second slots respectively 
disposed in the first and second hand frame members. The first and second 
hinges include respective first and second adjustable stop arrangements. 
The first and second adjustable stop arrangements are each disposable in 
at least: (i) a first mode allowing the first and second hand frame 
members to move at least over a 150.degree. range of motion relative to 
the first and second forearm frame members; (ii) a second mode with a 
range of motion less than in the first mode; and (iii) a third mode 
wherein the first and second hand frame members are fixed relative to the 
first and second forearm frame members. The inclusion of a fourth mode 
having a range of motion less than the second mode is also a feature of a 
preferred embodiment of the invention. The first and second adjustable 
stop arrangements each include a wide radial notch and a narrow radial 
notch and at least two stop pin receiving holes, and the range of motion 
of the brace is limited by the wide radial notch when a stop pin is in one 
of the stop pin receiving holes and the range of motion of the brace is 
limited by the narrow radial notch when a stop pin is in the other of the 
stop pin receiving holes. The first and second hinges extend respectively 
between the first and second forearm frame members and the first and 
second hand frame members and the first and second hinges are preferably 
made of radiolucent material such that an x-ray may be made of a patient's 
wrist without removal of the brace. Each of the first and second 
tensioners is an elastic band or other tensioning device (e.g., constant 
tension springs, etc.) adjustably mounted to an end portion extending 
between the first and second hand frame members. 
The present invention may alternately be described as a dynamic traction 
wrist brace comprising: first and second forearm frame members for 
disposal on opposite sides of a forearm cast; first and second hand frame 
members; first and second hinges respectively pivotably connecting the 
first and second forearm frame members to the first and second hand frame 
members, the first and second hinges operable to allow patient wrist 
motion; an end portion extending between the first and second hand frame 
members; and a transmetacarpal pin mounted to the first and second hand 
frame members and slidable in slots in the first and second hand frame 
members, the transmetacarpal pin operable to cause the first and second 
hand frame members to track movement of a patient's hand. The device 
further comprises first and second tensioners respectively attached to 
first and second sides of the transmetacarpal pin and adjustably mounted 
to the end portion. The end portion comprises first and second end frame 
members adjustably attached together and adjustably mounted to the 
respective first and second hand frame members such that the width and 
length of the brace can be adjusted to fit a particular patient. 
The present invention may alternately be described as a dynamic traction 
wrist brace comprising: first and second forearm frame members for 
disposal on opposite sides of a forearm cast; first and second hand frame 
members, the first and second hand frame members respectively attached to 
the first and second forearm frame members and allowing patient wrist 
motion; an end portion extending between the first and second hand frame 
members; a transmetacarpal pin mounted to the first and second hand frame 
members and slidable in slots in the first and second hand frame members, 
the transmetacarpal pin operable to cause the first and second hand frame 
members to track movement of a patient's hand; first and second tensioners 
respectively attached to first and second sides of the transmetacarpal 
pin; and first and second end frame members adjustably attached together 
and adjustably mounted to the respective first and second hand frame 
members such that the width and length of the brace can be adjusted to fit 
a particular patient. Each of the first and second tensioners is an 
elastic band adjustably mounted to one of the first and second end frame 
members. The device further comprises first and second hinges respectively 
pivotably connecting the first and second forearm frame members to the 
first and second hand frame members, the first and second hinges operable 
to allow wrist motion, and wherein the first and second hinges extend 
respectively between the first and second forearm frame members and the 
first and second hand frame members, and the first and second hinges are 
preferably made of radiolucent material such that an x-ray may be made of 
a patient's wrist without removal of the brace. The first and second 
hinges are each disposable in at least: (i) a first mode allowing the 
first and second hand frame members to move at least over a 150.degree. 
range of motion relative to the first and second forearm frame members; 
and (ii) a second mode with a range of motion less than in the first mode. 
The present invention also includes a method of using the wrist cast brace 
or wrist brace described above for the treatment of a fractured bone.

DETAILED DESCRIPTION OF THE DRAWINGS 
FIGS. 1 and 2, depict the overall structure of the device of the present 
invention. The dynamic traction wrist cast brace 10 of the present 
invention includes first and second forearm frame members 12F and 12S 
respectively. These forearm frame members 12F and 12S are respectively 
hingedly connected to first and second hand frame members 14F and 14S by 
respective hinges 16F and 16S. An end portion comprising first and second 
end frame members 18F and 18S are respectively mounted to the hand members 
14F and 14S. A transmetacarpal pin 20 having plastic end caps 22F and 22S 
is disposed within slots 24F and a corresponding slot (not shown) in hand 
frame member 14S. 
Elastic tensioners 26F and 26S are respectively attached to first and 
second sides of the transmetacarpal pin 20 by cord, wire, or other 
suitable means 28F and 28S. Alternately, the tensioners, 26F and 26S may 
comprise constant tension springs or any devices capable of imparting 
constant tension. The tension applied to the transmetacarpal pin 20 by the 
first and second tensioners 26F and 26S may be adjusted by virtue of first 
and second adjustable clamps 30F and 30S. As shown, each clamp includes a 
set screw 32F and 32S which are used to secure the clamps at different 
positions along the elastic cord 26F and 26S, thereby adjusting the 
tension on the pin 20. 
With further reference to FIGS. 1 and 2, and also considering the detailed 
perspective view of FIG. 3, the width adjusting and length adjusting 
features of the present invention are described below. Since the first and 
second sides of the brace 10 are symmetrical, it will be readily 
understood that the first hand member 14F and second hand member 14S are 
identically constructed. Likewise, the first and second end members 18F 
and 18S are identically constructed. The first hand member 14F is secured 
to the end member 18F by use of a plurality of holes 34F in the end frame 
member 18F. These holes (only some of which are labeled) cooperate with 
similar holes in hand frame member 14F. First and second screws 38F1 and 
38F2 are used to secure the end frame member 18F to the hand member 14F. 
The cooperating holes in hand member 14F are identical to the holes 36S 
shown for the second hand frame member 14S. Likewise, the screws 38S1 and 
38S2 are used for securing the second end frame member 18S to the second 
hand member 14S. 
The end frame member 18S further includes a series of holes 40S into which 
screws 42 may extend. The screws 42 would further extend through holes in 
end frame 18F which are identical to the holes 40S in end member 18S. 
Depending upon the placement of the screws 38F1, 38F2, 38S1, 38S2, and 42, 
the brace 10 can be adjusted to accommodate differing lengths and widths 
depending upon the patient's size. 
As shown in FIG. 3, the tension cords 26F and 26S extend through holes 44F 
and 44S in the respective end members 18F and 18S. 
The specific features of the hinge 16F construction are shown in FIGS. 4 
and 5. It will be readily appreciated that the hinge 16S is constructed 
identically to hinge 16F. 
The hinge 16F comprises a forearm piece 46A which is riveted to the forearm 
frame member 12F, and a hand piece 46H which is riveted to the hand frame 
member 14F. The pieces 46A and 46H are hingedly connected by hinge pin 48. 
The piece 46A includes a wide radial notch 50W and a narrow radial notch 
50N as shown. The notches 50W and 50N are part of an adjustable stop 
arrangement further including holes 54A, 54B, 54C, and 54D spaced at 
90.degree. angles around the hinge pin 48. The holes 54A and 54B are 
disposed in piece 46H, whereas the holes 54C and 54D are shown for piece 
46A. A hole is provided in piece 46H in registry with the position of hole 
54C in FIG. 4. A screw 52, which functions as a stop pin, is shown 
disposed in the hole 54A. 
With the stop pin or screw 52 disposed in hole 54A as shown in FIG. 4, the 
range of motion of hand member 14F relative to forearm member 12F is 
limited by the edges of the radial notch 50W. This radial notch 50W is 
preferably about 60.degree., thereby allowing a 30.degree. range of motion 
in each direction from the position shown in FIG. 4. When the stop pin 52 
is screwed into hole 54B, the narrow notch 50N determines the range of 
motion. The narrow notch 50N preferably has a total angle of about 
30.degree. (or 20.degree.), thereby allowing a 15.degree. (or 10.degree.) 
movement of hand member 14F in each direction relative to the forearm 
member 12F. By placing the stop pin 52 in the hole 54C and the hole in 
piece 46A just underneath 54C in FIG. 4, hand member 14F will be locked 
approximately in line with forearm member 12F. By screwing the stop pin 52 
into hole 54D and the hole in piece 46A underneath hole 54C in FIG. 4, 
hand member 14F and forearm member 12F may be locked at 90.degree. to each 
other. The hole underneath hole 54C in FIG. 4 will, of course, be 
underneath and in registry with hole 54D after hand member 14F has been 
rotated 90.degree. with respect to forearm member 12F. 
An important feature of the hinge 16F and 16S is that they can be 
constructed of fiberglass resin or other material which is radiolucent. 
This allows an x-ray view in lateral direction without obstruction and 
without requiring removal of the brace. These materials also provide an 
inherent lubricity which facilitates smooth motion with the plastic heat 
fusable rivet hinge pin 48. The various frame members are preferably made 
of aluminum and would tend to block x-ray views, whereas the use of the 
fiberglass resin for the hinges 16F and 16H will avoid the need for brace 
removal prior to x-ray. 
Obviously, the screw or stop pin 52 may be removed totally from any of the 
holes in the hinge 16F to allow a free range of motion between 14F and 
12F. This range of motion is greater than 150.degree. and may be 
considered as a first mode of operation, whereas the placement of stop pin 
52 in either hole 54A or hole 54B can be considered as a second mode of 
operation with a narrow range of motion. The placement of pin 52 in either 
hole 54C or 54D can be considered a third mode of operation with the hand 
members 14F and 14S fixed to forearm members 12F and 12S. 
As shown in FIGS. 1, 2 and 4, the present brace 10 is adapted to work with 
a standard forearm cast 60 including a notch 62 for accommodating the 
upper arm and allowing relative flexion-extension of the elbow. The 
configuration does not allow pronation-supination, i.e., rotation about 
the long axis of the forearm. 
Operation 
The present invention is useful for a distal radius fracture (especially in 
a patient below the age of 35 years) involving the articular surface of 
the radiocarpal joint and wherein the joint cannot be maintained in 
acceptable alignment by conventional methods. 
Following closed reduction and sugar tong application to bring the bones 
into alignment from the above described fracture configuration, elective 
metacarpal pin placement is carried out. This is performed with the use of 
regional intravenous anesthesia. A long arm cast which terminates proximal 
to the radial and ulnar styloid with the forearm in supination is applied 
as soon as a satisfactory closed reduction has been achieved. The hinged 
frame and traction tubing or tensioners 26F and 26S attached to the 
metacarpal pin 20 are then incorporated into the long arm cast allowing 
for wrist motion, dorsiflexion, and palmarflexion. The slots 24F and 24S 
(not visible in the drawings) allow the traction tubing or tensioners 26F 
and 26S to distract the carpus and allow reduction of the fracture 
fragments. Post-cast brace radiographs are obtained to assess the 
alignment and indicate if any adjustments are necessary. A volar wrist 
splint comprising ORTHOPLAST or other moldable plastic splint material is 
fabricated and used between range of motion exercises. Appropriate tension 
on the pin 20 will be determined by the fracture configuration, soft 
tissue tolerance, and instability. 
When a patient is wearing the brace 10 and the associated cast 60 the notch 
62 will be disposed to allow flexion-extension of the elbow but blockage 
of pronation and supination. The hinge pin 48 in hinge 16F and the 
corresponding hinge pin in the hinge 16S will be placed in line with the 
patient's wrist joint. The transmetacarpal pin 20 will extend through the 
patient's hand and distract the patient's carpus by virtue of the 
adjustable tension placed on pin 20 by tensioners for traction tubing 26F 
and 26S. 
As best shown in FIG. 3, the traction tubing or tensioner 26F (and 26S) may 
include a series of notches 58 which may be calibrated to allow for easy 
adjustment of the traction tension. 
A more detailed outline or protocol of the operation steps may be presented 
as follows: 
(1) Routine Bier Block (application of local anesthetic) 
(2) Place Rolled Stockinette onto Proximal Forearm 
(3) Place Fingers in Finger Traps with 10 Pounds Counter Traction Over the 
Arm 
(4) Place Plastic Towel Drape Around Midforearm 
(5) Prep Hand with Betadine (antiseptic) 
(6) Pin Placement (The pin goes through second and third metacarpal bone) 
(a) 7/64 Threaded Pin 
(b) Abduct Thumb 
(c) Incise Skin at Junction Proximal/Middle 1/3 Second Metacarpal 
(d) Flex MP Joints Index-Ring Fingers 
(e) Insert Metacarpal Pin 
(7) Reduce Fracture 
(8) Locate Wrist Joint with Radiopaque Marker Taped on Radial Border (thumb 
side) of Wrist 
(9) Check AP/Lateral x-rays 
(10) Improve Reduction as Necessary 
(11) Unroll Stockinette, Webril and Fiberglass Cast with Elbow in 
90.degree. Flexion and Forearm Supinated with Cast from Upper Arm to just 
Proximal to Styloid Processes 
(12) Traction Maintained on Pin while Brace Applied with Center Axis of 
Hinge Corresponding to Axis of Wrist Joint, as Marked With Marker in #8 
Above. Secure Hinges to Cast with Fiberglass Tape 
(13) Adjust Tension Cords 26F and 26S to 2 Lbs. of Counter Traction (The 
actual tension can be varied depending on the physician's judgement with 
respect to fracture configuration, soft tissue tolerance and instability) 
(14) Remove Countertraction and Recheck AP/Lateral x-ray 
(15) If x-ray o.k., Release Tourniquet 
(16) Trim and Cap Pins 
(17) Followup 
(a) Fix hinge in Neutral (no motion allowed) for 3-5 days 
(b) Begin Active & Passive Finger Range of Motion Exercises as Soon as 
Possible 
(c) Begin 15.degree. or 10.degree. arc Wrist Motion at 3-5 Days (pin 52 in 
hole 54B) 
(d) Begin 30.degree. arc Wrist Motion at 7-10 Days (pin 52 in hole 54A) 
(e) Begin Unlimited Wrist Motion at 14-18 Days 
(f) May Require Volar Wrist Splint when Restraints Removed for Night Use 
As noted in step 17 above the hinge of the present invention may be fixed 
for the first few days such that no wrist motion is allowed. The physician 
may increase the allowable range of motion by moving stop pin 52 as the 
healing process gets underway. 
Although the present description has included specific construction details 
and materials, it will be readily understood that these are for 
illustrative purposes only. Various modifications and adaptations will be 
readily apparent to those of ordinary skill in the art. Accordingly, the 
scope of the present invention should be determined by reference to the 
claims appended hereto.