Clinical Experience with Functional
Fracture Bracing of the Tibial
Diaphysis
Walter L. Racette, CPO
Introduction
Using orthoses in the management of fractures has evolved from a "last-resort" treatment to common practice. Acceptance of
functional fracture bracing as a routine treatment has not been without controversy. Using an orthosis for acute tibial fractures-
and thus allowing joint motion-was a 180degree reversal from the accepted methods
of the times, rigid immobilization with no
weightbearing.
Skilled application is important, and numerous articles, videos and brochures describe and illustrate procedures. However,
several critical points are often missed and!
or diluted when discussing how to brace tibial fractures. Several successful clinically
proven prefabricated fracture braces are
available. However, without an understanding of the philosophy, indications and contraindications, clinical practice, patient instructions, skin care, etc., these prefabricated fracture braces will lead the inexperienced to unsatisfactory results and an incorrect condemnation of the method.
Simply stated, knowing who to brace is as important as knowing how to brace. This article will summarize the evolution of the fundamental principles and practice of functional fracture bracing of the tibia. There has
been an increased acceptance and use of this
method of treatment because of a more
clearly defined protocol and the availability
of prefabricated devices that reduce the
amount of necessary fabrication experience.
The simplicity of prefabrication and application should not in any way disguise the necessity of adherence to and understanding of
the functional fracture brace philosophy and
methodology.
Principles and Design of
Functional Fracture Bracing
A major principle of functional fracture
bracing is that early restoration of function
and graduated weightbearing (in keeping
with tolerance and the minute motion that
results) is beneficial to fracture healing (1).
To adhere to this principle, the orthosis
should not restrict range of motion either by
a low/high trimline or by a mechanical lock
at the joint (see Figure 1
). Patients must be
encouraged to increase their range of motion
after their primary immobilization in a plaster-of-paris cast, which necessarily limits
movement, to give the soft tissues an opportunity to heal and the symptoms to subside.
To encourage compliance, the orthotist
should gradually range the ankle joint to the
limits of the patient's tolerance at the time of
application. At the one-week evaluation
exam, the orthotist must check the trimlines
to ensure they do not restrict motion.
Weightbearing must be encouraged. With
the patient using appropriate support, initially two axillary crutches, weightbearing/
ambulation should be done as soon as the
brace is applied, and gradually increased as
symptoms subside and healing progresses.
Unfortunately, because this is such a departure from other methods of treating the tibial
fracture, many practitioners do not make the
move from principle to practice. They either
decide not to have the patient weightbear or
they suggest it is optional.
A trimline that restricts joint motion or a
mechanically locked knee joint lock will
cause undesirable motion and possibly malalignment of the fracture site. By not allowing
and encouraging weightbearing, a significant
increase in edema at the foot results. The
properly fit fracture brace will restrict blood
return and cause some edema, but weightbearing and ranging the joint will help control the situation. Proper elevation and shoe
wear are also essential. Fear and traditional
thought cause most patients to be ultra-cautious with motion and weightbearing. It must
be communicated in a positive way that motion and weightbearing are highly desirable.
The ability to contain the soft tissue mass
between the joints, producing a hydraulic
effect, is a major factor in the success of
functional fracture bracing (2). The brace
provides the mechanism to maintain the hydraulic effect and load soft tissue, and along
with pain and the interosseous membrane, to
maintain fracture alignment. Using a plaster-of-paris bandage (and more recently,
synthetic casting tape) has played a role in
the evolution. However, these materials do
not readily comply to the principle of containing soft tissue. Often, the circumference
of the calf decreases by 1 1/2 inches and the
ankle decreases by 1/2-inch the first week
post-application.
Since these materials provide a rigid static
cylinder, they do not adjust to maintain circumferential pressure. Therefore, they do
not load soft tissue, and they limit patients'
ability to bear weight (see Figure 2
). A patient-adjustable brace is a must in adhering
to the fundamentals of functional fracture
bracing. The patient realizes a snug brace
makes the leg feel more secure and reduces
pain. Generally, a brace that is worn loosely
indicates tightness over a bone prominence
that must be relieved. It must be emphasized
to the patient that this is an adjustable brace,
not a removable brace.
Elderly, minimally active patients who
wear femoral-style orthoses for distal femoral or proximal tibial fractures should have
synthetic or plaster-of-paris bandages that
wrap the foot to the tibial section. This prevents the inevitable distal migration that
causes malleolus pressure, femoral condyle
pressure and/or heel cup pressure. In more
active patients, proper footwear will minimize this problem.
Brace design and materials should be selected for their ability to adapt and adjust to
the normal volume fluctuation so as to continually maintain the hydraulic environment.
Rigid non-yielding plastics only reproduce
the undesirable features of plaster-of-paris
and synthetic bandages. Proper thicknesses
of low-density polyethylene and co-polymer,
thinner rather than thicker, provide an excellent adjustable container. Polyethylene is
much easier to work with and much easier on
the skin than polypropylene. Polypropylene's rigidity causes pressure on the skin of
the fractured extremity and generally is far
more difficult to open when donning.
Patient Management
Treatment methods may also be chosen according to when a fracture occurred. Although orthoses are used to treat both nonunion and acute fractures, treatment methods and patient management vary dramatically. Using so-called weightbearing orthoses as limb substitutes for non-union fractures dates back to the last century (3). Orthotic care has evolved, resulting in better
use of materials; however, these treatment
differences must be recognized. Orthotists
must know what they are treating, clinically
and radiologically.
Orthotists must ask several questions before removing any cast in preparation of
bracing an extremity. How long has it been
since you fractured? What was the nature of
injury? Was the fracture open or closed?
Were there any additional associated injuries? The answers to these questions will
serve as the basis for timing brace application and give some indication of what to expect when the cast is removed. More trauma
and associated soft tissue damage would indicate a longer time before brace application
so as to give those soft tissues a chance to
heal and stabilize.
Most closed fractures can be successfully
braced three and four weeks after fracture,
allowing for differences in soft tissue damage
and individual tolerance to pain. These patients are generally in some degree of pain,
and the orthotist must be prepared for much
different circumstances than in treating a patient with a year-old fractured extremity. No
truer words were said than "treat a patient,
not a fracture."
Have ammonia capsules readily available,
and observe the patient constantly during
the procedure. Patients respond very differently when seeing their extremity bending at
the fracture site and in their tolerance to
pain. Patients should not be given pain medication before the procedure. It is far better
for the patient if the clinical team delays the
application and allows symptoms to subside.
Patients who are wearing casts, complaining
of pain and experiencing marked edema will
usually be even more uncomfortable after
being placed in a brace. Patients rarely benefit from or tolerate tibial brace applications
performed less than two weeks from the date
of injury.
Most closed tibial fractures can be braced
within four weeks. Open fractures are different and will be addressed later. Fracture
bracing should not be considered as primary
care following injury. All closed fractures in
our experience were initially treated in a toe-to-groin long leg cast.
The brace contains the soft tissue, and the
soft tissue supports the fracture site. Therefore, having knowledge of the nature of injury will aid the orthopaedist and orthotist in
determining how unstable the extremity is,
which direction force created the fracture,
and to some degree, the probability of the
re-occurrence of malalignment. The greater
the force, obviously the less soft tissue supments to allow for possible increased initial
swelling and subsequent reduction in volume.
Viewing the X-ray and consulting with the
orthopaedist prior to application is vital, not
only for the patient, but also for the clinic
team's long-term experience (see Figure 3
).
Exactly what information can be obtained by
viewing the X-ray?
Besides the obvious level of fracture and
fragment pattern, one can
- estimate any angulation present that
may be improved during application;
- see an indication of the direction of
force to get an idea of soft tissue instability;
- see an anterior displacement of the
proximal fragment that may require brace
modification (as opposed to an apex anterior
where you would not want to modify the
anterior brace section);
- find the existing angulation plus the time
from injury.
The consultation prior to application is
fundamental in the development of the clinical team. And it indicates the necessity of
two other requirements for long-term success: first, the need for the orthotist to communicate with the orthopaedist and patient,
and second, to view and consult the post application brace X-ray as necessary. The
orthotist must be able to travel outside his
office for the acute fracture brace application. One cannot expect, as is the practice in
non-union bracing, that the physician will
send the patient across town so the orthotist
can remove the bivalved cast, apply the
brace and send the patient back that day for
post-application X-rays, or worse, to take a
cast for a custom fracture brace before reapplying the bivalved cast.
The practice of the patient going to the
orthotist for cast and measurement to fabricate custom orthoses for non-unions is acceptable. However, there are major differences. Acute fractures are more painfully
unstable-there is more urgency for X-ray
follow-up, and the vast majority of acute diaphyseal tibial fractures can be fitted with a
cost-effective pre-fabricated brace. The custom orthosis will take considerably more time and work than are required for non unions since this orthosis may be worn indefinitely. The orthotist is the logical choice to provide skilled application of the functional
fracture brace. He has experience with many
different materials and equipment; knowledge of anatomy, physiology, kinesiology,
etc.; the ability to provide both consultative
expertise, as well as several types of orthoses, depending on the patient's needs; and
the ability to customize any orthosis in accordance with the specific fracture needs and
trauma other body segments may have received.
The orthotist should view all post-brace
application X-rays. Obtain an X-ray immediately after the application to check for any
change in alignment during the transfer from
cast to brace. In some instances it may be
desirable to correct a minor amount of malalignment. A two- to four-week-old fracture
moves easily, so this can be accomplished.
By viewing post-brace films, the orthotist
can gain valuable information about the results of his efforts, including uniformity of
brace fit, possible pressure on bone prominences, malalignment correction forces and
mechanical joint alignment relative to an anatomical joint. Viewing non-union post-brace films is beneficial, but it is more urgent
to view X-rays of acute fractures since the
ability to improve alignment decreases and
the force required to do so increases as time
passes.
Obviously, individual fractures heal and
gain stability at different rates. Acceptable
alignment must be achieved at the time of
the initial reduction and maintained during
primary care; good initial reductions can be
maintained throughout brace treatment.
The routine use of a fracture brace to transform an unacceptable alignment into an acceptable one must be discouraged.
Some Guidelines
Length. The amount of shortening must be
acceptable at the time of brace application
since no brace application can be expected to
reestablish lost length. Closed fractures
shorten 3/8-inch in a vast majority of cases
(2). Generally, unacceptable length loss occurs in open fractures where major trauma
has occurred to bone and to soft tissue. External fixators, pins and plaster, and intramedulary rods can be used to regain length.
Rotation. The rotation stability of a tibial
fracture is established early, and it is critical
to correct malrotation at the time of initial
reduction. It is extremely difficult and painful to try to correct a malrotation of the tibia
later with a long leg cast.
Varus/Valgus. The correction of valgus is
accomplished with little force if done in the
two- or four-week period prior to the fibula
gaining stability. For valgus to occur in the
fractured tibia, the fibula must also be either
fractured or, in rare cases, dislocated at the
head. Once the fracture reaches five to six
weeks post-injury, unacceptable valgus must
be corrected with a moldable material like
Orthoplast. When doing a valgus correction,
it is common to underestimate the force required to improve the situation. It is extremely difficult to over-correct a valgus deformity.
Varus is usually associated with an isolated tibial fracture and is difficult to correct at
any time. One must expect a few degrees of
varus to occur with an isolated tibial fracture
once weightbearing is allowed (4). This will
occur both in a plaster-of-paris long leg cast
or in a functional fracture brace.
Three to five degrees of varus is common
and usually judged to be acceptable by most
orthopaedists. Correction of varus is difficult
because the effectiveness of the three-point
pressure system hinges on the intact fibula,
which rarely yields much correction, plus an
element of associated rotation.
Apex Posterior/Anterior. Apex posterior
or angulation is difficult to correct because
the force of the three-point pressure system
is dissipated in soft tissue and because the
distal 1/3 fracture has a short lever arm. The
position of the ankle/foot in the cast is a
major cause of apex posterior. In many cases
the initial reduction may have had the foot in
10 to 15 degrees of equinus, and when the
patient was transferred to a brace, the lever
arm malaligned the fracture. Patients should
have the equinus in a cast reduced to avoid
this possibility.
Apex anterior is another very common,
easily corrected malalignment. It is common
because the helpful patient raises his leg, and
it hinges anterior or at the fracture. Correct
the problem by pulling the heel forward and
making the apex (bony prominence) disappear. This correction can be made later in
the process, five to six weeks, unlike other
malalignments.
The orthotist must view the X-rays and
consult the orthopaedist prior to application
to achieve these improvements. In most
cases, the physician should correct or assist
the orthotist. Never attempt any correction
without first advising the patient and showing him/her the correction you are making on
X-ray. Close cooperation and communication between the orthopaedist and the orthotist are essential to obtaining good results.
Considerations
Different levels and patterns of fracture of
the tibia respond differently to functional
fracture bracing (4). It is important to understand the nature of these fractures as some
may be a contraindication to orthotic treatment and others may require modifications
in treatment protocol or the brace itself.
Proximal 1/3 tibial fracture. The condition
of the fibula is important in treating any tibial fracture. The tibial fracture at this level
without an associated displaced fibular fracture is a contraindication for bracing. The
fibula will support length, and its strut effect
upon weightbearing will allow unacceptable
varus to occur.
The proximal 1/3 tibial fracture with an associated displaced fibula fracture can be
braced. Patients with fractures at this level
have significant swelling in the upper leg,
and it is necessary to allow for two to three
inches downward reduction in size. It is also
critical that the posterior proximal trimline
be low enough so as not to restrict knee motion. If it is too high, it will act as a fulcrum
during flexion and create an apex anterior
angulation. The highest level for which a below-the-knee orthosis can be used (considering the previous contraindication) is at the
level of the tibial tubercle. Certain transverse fractures of the isolated tibia can be
braced as they tend to be somewhat stable,
but do require close observation.
Midshaft tibial fractures with associated
displaced fibula fracture can be braced. Special attention is required for the patient with
large, heavy calf structure, especially if significant associated soft tissue damage occurred, since these fractures tend to be very
unstable. Isolated tibial fractures have a tendency to angulate toward varus, but usually
within acceptable limits. The time to union
in these patients can be significant, especially when bone fragments are not in direct
contact with minimal displacement.
Distal tibial fractures and associated displaced fibula fractures are candidates for
early bracing and weightbearing. The foot
has a tendency to swell more because of its
proximity to the fracture site. The distal anterior trimline must not restrict motion; if it
is too low, it can act as a fulcrum and cause
an apex posterior angulation. Tibial fractures with nondisplaced fibula fractures will
usually result in a few degrees of varus. Individual case decisions dictate acceptability/
nonacceptability. The foot position in the
cast is critical. Often, equinus is created in
the cast at the time of application to reduce
the fracture. Equinus of 10 to 15 degrees or
more should be placed in a below-the-knee
cast with the equinus reduced and alignment
maintained since putting these patients directly into a brace is a contraindication.
Brace design does not vary drastically for
the care of all tibial fractures using a below-the-knee orthosis. The main change is one of
material choice. About 85 percent of these
fractures can be braced with a clinically proven prefabricated orthosis. The main features
should be a thin, well-conforming anterior
section that has 1/4-inch closed-cell foam padding down the anterior tibial crest section,
flaring out posteriorly in the distal 1/3 to allow
for comfort over the malleolus after distal
trimming.
The foot section must be separate from the
anterior tibial section at the time of application so it will be adjustable and not restrict
ankle motion. The shoe insert's main purpose is to maintain the heel in correct anterior/posterior position and to hold the tibial
section statically at the correct height to allow for the effects of soft tissue loading. The
posterior closure should be kept thin to keep
tissue from bulging out and being pinched.
The adjustment straps should be strong and
durable. Different fracture situations require use of two other types of below-knee
orthoses that have the same design but are
made of different materials.
Orthoplast, a direct-contact moldable
plastic, should be used for patients with major soft tissue damage resulting in changes of
normal shape, for individuals who are outside the prefabricated size range and for fractures that require a substantial corrective
force. This material has unique features. It is
flexible when heated to 180° and then becomes rigid as it returns to room temperature. Ice-soaked ace wraps speed the process. Typically, the five- to seven-week-old
fracture requiring improvement in alignment
is best cared for with this material. Once
cool, the brace should be made adjustable,
using the prefabricated posterior tongue,
Velcro placed on the medial and lateral side,
and a prefabricated shoe insert fit.
Non-union and delayed union fractures
may require a custom-made polyethylene
(low-density) anterior section with appropriate closed-cell foam padding. The posterior
tongue and single-axis shoe insert should be
of the same design. As a general rule, the
longer the time from injury to brace application, the greater the possibility custom-molded and custom-manufactured braces
will be indicated.
Open fractures. When injury results in
fracture and the bone penetrates the skin,
care takes on other considerations. Usually
the result of higher velocity injury, there is
more soft tissue damage, shortening, drainage and fracture instability. Frequently, the
initial treatment will involve pins and plaster
or an external fixation device.
These patients can be braced, but only
after some intrinsic soft tissue stability has
developed and wound healing has occurred,
generally in five to six weeks. The patient
can be braced only if s/he has only minor
amounts of drainage, that which one thickness of 4-inch x 4-inch bandage could absorb,
and if s/he can change the dressing daily (see
Figure 4
). Do not use a thick dressing under
the brace because it will only create a larger
wound due to pressure from the brace. It is
best to gain experience bracing closed fractures before treating open fractures. By nature, these fractures are more unstable and
need closer observation.
The skin of a fractured extremity under a
fracture brace needs different attention than
that under plaster-of-paris or synthetic bandages. Unlike these materials, plastic does
not absorb moisture, drainage or blood. Using a specially designed sock is essential.
Substituting cotton stockinette will cause significant problems. The fracture sock is similar in thickness to a three-ply residual limb
sock so it can dissipate heat and move moisture away from the skin. The sock should be
changed at least once a week.
All patients must be seen for a routine
follow-up one week post brace application.
Take X-rays and perform an orthopaedic examination, brace review and sock change
(5). At this time, the orthotist should show
the patient how to change the sock him/herself. Patients who do not follow instructions
should have the brace removed and only use
plaster-of-paris casts. Heat maceration and
various contact dermatitis will result if a wet
sock is left under the brace for an extended
period and/or if lotion and powder are used
on the limb. Many problems can be resolved
by changing the sock every other day.
Ventilation holes in the anterior section
and heel cup are essential. The brace should
only be removed to change the sock and
quickly clean the extremity. As the extremity shows clinical signs of stability, the orthopaedist may let the patient remove the brace
during sleep, and gradually, as symptoms
dictate, wean the patient from use.
The orthotist should appreciate that the
skin about the fractured extremity does not
tolerate pressure as well as the non-fractured
extremity in an orthosis. Besides the obvious
swelling, skin temperature remains higher,
the fracture is painful if pressure is removed
and wearing the orthosis is a 24-hour regimen. Patients' pain sensation focuses at the
fracture, and many times they will not be
able to notify you of pressure located elsewhere. Great care and time must be taken to
fit the prefabricated brace to the extremity.
An area that is snug initially may be much
too tight after continuous wear. Heating and
rolling the edges of the brace in the anterior
distal tibial section, the head of the fibula,
the popletial area and the tendo achilles are
essential.
Internal Fixation
and Fracture Bracing
The combination of internal fixation (plates
and screws) and functional fracture bracing
is not advisable. The philosophy of each
method contradicts the other. Rigid fixation
with nonweightbearing versus non-detrimental motion at the fracture site with
weightbearing do not complement one another. Once internal fixation has been accomplished, the length of the extremity has
been determined and loading of soft tissue
via a fracture brace is not possible. In situations where used in combination, the fracture brace only functions as an expensive
removable cast-type support. The use of intramedullary rods and fracture bracing
seems to complement each other, but to use
a fracture brace after intramedullary rodding
may not be cost-effective if done routinely.
Patient Instructions
The clinical team-the orthopaedist, orthopaedic nurse and orthotist-must reinforce
and repeat patient instructions. As opposed
to treatment in casts, the patient plays a major role, for s/he must perform several functions during treatment that are vital for acceptable results.
Patients must
- learn how to tighten the brace,
- understand the necessity of adjustability,
- bear weight on the extremity according
to pain tolerance and gradually increase the
amount borne, and
- use continuous range-of-motion exercises in the affected joints.
Initial weightbearing should be accomplished with the aid of two axillary crutches,
then gradually, as symptoms subside and stability increases, to one crutch and so on.
Once the brace is placed, the orthotist
should straighten the extremity, support the
knee and, with the patient's foot on his
thigh, gradually load the extremity to demonstrate and encourage weightbearing. The
patient should be instructed to take short
frequent walks, then sit with the extremity
elevated. It is not advisable for patients to
stand with nonweightbearing on the hanging
fractured extremity for long periods of time.
Proper shoe wear is an essential part of
bracing methods (see Figure 5
). It is not a
"can wear," but a "must wear." Instruct the
patient prior to brace application to bring or
obtain a tennis-type shoe. When the shoe is
worn directly after brace application, rarely
will a larger size than normal be required. If
this detail is left for a few days, then larger
sizes will be the result. The shoe, besides
providing a safe surface for ambulation, can
accommodate the normal amount of edema
patients will have and acts as a control to
limit edema. The shoe must be donned first
thing in the morning. Patients who do not
comply with these instructions should be
placed back in a cast.
At the one-week follow-up, the orthotist
must demonstrate the process of changing
into a clean sock and emphasize the need not
to separate the anterior tibial section from
the shoe insert. These separate components
are to facilitate application and size adaptation, but once fitted should not be separated
except by the orthotist. If the anterior distal
trimline is too low, this process is difficult
and trimming should be done. A sure sign
that the patient has separated these two components is that the anterior section is always
replaced much lower than it should be and
besides the risk of malalignment, normal
range of motion will be blocked. It is essential the patient play an active role in his/her
care and have a general understanding of the
procedure. Patient instructions should be incorporated into a written handout for the
patient to take home.
Using functional fracture bracing for certain tibial diaphyseal fractures has proven to
be successful. This method has limitations
and is not suitable for all long-bone fractures. Bracing should be discontinued and
other therapeutic modalities introduced if it
fails to provide and/or maintain the desired
stabilization and alignment of the fractured
fragments. Its success seems to be determined by a clear understanding of its philosophy and principles, and by rigid adherence
to technical details.
WALTER L. RACETTE, CPO, is general manager of patient care, Camp Ltd., UK. Previously,
Mr. Racette was clinical instructor in orthopaedics,
Department of Orthopaedics, University of Southern California.
References:
- Latta L, Sarmiento A, Tarr R. The rationale
of functional bracing of fractures. Clinical Orthopaedics and Re!. Res. January-February
1980; 146:28-36.
- Sarmiento A, Latta L. Closed Functional
Treatment of Fractures. Springer-Verlag. New
York, 1981.
- Sarmiento A, Sinclaire WF. Prostheticsorthotics principles in orthopaedics. Artificial
Limbs 1967;2:2.
- Sarmiento A, Sobol P, Sewhay A, Ross S,
Racette W, Tarr R. Prefabricated functional
braces for the treatment of fractures of the tibial
diaphysis. The Journal of Bone and Joint Surgery
December 1984;13:28: 1338.
- Sarmiento A, Racette W. Specialist Preformed Tibial Fracture Brace Technique. Johnson
and Johnson Products, Orthopaedic Division,
1982:3.
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