OVERVIEW AND DESCRIPTION
Terminology: Orthosis is the medical term for a brace while orthoses is the plural form. The term orthotics refers to the science and practice of patient assessment, fabrication, fit and adjustment of an orthosis. Orthotic device can be used interchangeably with the term orthosis. An orthosis or orthotic device is applied to the body to modify or control skeletal structure or function. A basic principle for limb orthoses is to use three points of pressure to perform at least one of the following functions: 1) stabilize or immobilize a body part; 2) improve alignment; 3) prevent deformities; 4) protect against injury; 5) assist with motion, 6) off load a joint or body part or 7) improve function. Orthoses are named for the joints/segments they manage according to the International Organization for Standardization (ISO), and are classified based on action (static vs. dynamic or accommodative vs. corrective).
Other terminology useful to consider in orthoses includes understanding the differences between custom versus off the shelf orthoses, dynamic versus static orthoses. “Off the shelf” orthoses are prefabricated, mass-manufactured that are available in various orthotic designs, shoe sizes and materials. Custom molded orthoses refer to those made specifically for individual patients.
A static orthosis has no motion across the joint or segment involved. A dynamic orthosis indicates that there is motion across the joint. A static progressive orthosis is a type of mobilization orthosis that applies force to a joint and hold it in its end range position with a goal to improve passive joint range of motion.1
Orthoses in acute injury tend to focus on maintaining range of motion, preventing contractures, managing pain, protecting damaged or weakened soft tissue, or providing immobilization. Chronic orthosis use aims to prevent or control unwanted motion, enhance desired motion, decrease abnormal tone, alleviate pain, or maximize function. These interventions apply to all phases of a rehabilitation plan and depend on the patient’s level of impairment.
Some medical conditions which warrant the use of limb orthoses or therapeutic footwear may include: trauma, stroke, brain injury, spinal cord injury, multiple sclerosis, cerebral palsy, peripheral nerve injury, peripheral neuropathy, arthritic conditions, burns, hypotonia, hypermobility, neuromuscular disorders, and contracture management in both pediatric and adult populations.
Common complications that can be seen with orthotic management include pressure injuries, infection, and pain. Thus, it is essential that special attention made to examine the skin, neurological function, vascular status, and musculoskeletal system in patients who will be using an orthosis.
2. RELEVANCE TO CLINICAL PRACTICE
Upper Limb Orthoses
Upper limb orthoses differ in scope and purpose from lower extremity orthoses due to the functional difference between fine motor control in upper extremity and gross motor control and weight-bearing in the lower extremity. 1
Upper limb orthoses generally focus on achieving a functional range of motion rather than seeking to achieve a normal range of motion.
- Commonly used for intrinsic hand musculature weakness or paralysis with intact wrist extensors.1
|Type of Hand Orthoses||Action of the orthosis||Goals/ Indications|
|Thumb adduction stop orthosis (“C-bar orthosis)||Maintains the thumb web space and position of the hand||Increase the ability to perform functional task(s) with thumb in abducted position|
|Thumb spica orthosis||Provides support for positioning of the thumb carpometacarpal and metacarpophalangeal (MCP) joints||Decrease pain and/or provide thumb stability in patients with osteoarthritis, hypermobile joints and/or thumb instability|
|Thumb interphalangeal (IP) orthosis||Provides support to weak extensor pollicis longus||Support weak muscles|
|Metacarpophalangeal (MCP) extension stop orthosis||Stops MCP hyperextension to support transverse arch weakness||Maintain functional hand position when recovery of strength is expected|
|Proximal interphalangeal joint orthosis (PIPO)||Blocks exaggerated displacement of the joints||Boutonniere or swan neck deformity|
Wrist-hand orthoses (WHOs):
- Resting WHOs preserve wrist and hand architecture by positioning the wrist and hand in functional alignment with the thumb abducted and flexed.
- Dynamic WHOs protect and assist weak wrist extensors by transferring power from active wrist extension into finger flexion by utilizing tenodesis.
- Dynamic dorsal WHOs for radial nerve injuries position the hand with wrist and MCP in extension.1
Elbow orthoses (EOs):
- EOs address functional limitations caused by soft tissue contractures at the elbow. O
- EOs are used after surgery or trauma for limb stabilization instead of casting. These can be static or dynamic
- Functionally, dynamic EOs are commonly used for assistance with elbow flexion in patients with weak elbow flexors.1
- Static elbow-wrist-hand orthoses (EWHOs) are used for fractures such as those involving the radius/olecranon and distal humerus.
Shoulder-elbow orthoses (SEO):
- SEO supports the shoulder to reduce pain and/or provide position due to muscle weakness, e.g., brachial plexus injuries or shoulder subluxation after stroke.
- A mobile arm support SEO (MAS-SEO) is used in severe arm paralysis to improve limb function by supporting the weight of the arm while assisting shoulder and elbow motion by reducing the effects of gravity and are used in a seated position (often in a wheelchair).1
Shoulder-elbow-wrist orthoses (SEWO):
- SEWO are used post-operatively in rotator cuff and anterior-posterior capsular repairs to relieve tension on the deltoid and rotator cuff. SEWO externally rotate the glenohumeral joint and stretch the shoulder internal rotators while protecting soft tissue and preventing contractures.1
Other upper limb orthoses:
- Typically, tone reduction orthoses are used to reduce flexor tone in patients with significant spasticity. One example is a Bobath finger spreader orthosis that uses digit abduction to decrease finger flexor tone.
Lower Limb Orthoses
Ankle foot orthoses (AFOs):
- AFOs are commonly prescribed for weakness of ankle dorsiflexors, plantar flexors, invertors, and evertors. AFOs improve gait deviations by taking advantage of ground reaction force, such as, controlling the progression of the tibia over the ankle and limiting knee flexion and/or extension during stance. An AFO can also assist pre-swing phase toe off and foot clearance during swing phase.
- Carbon fiber AFOs are effective for patients without abnormal tone and neutral foot alignment with distal muscle weakness.2
|Type of Orthosis||Mechanism||Indications|
|Double up right AFO||Metal AFO that can control ankle movements with pins and springs (see below for details)||Fluctuating edema; Insensate feet at risk for pressure wounds|
|Semi-rigid plastic AFO||Pressure point at the anterior tibia can assist with knee extension during the mid-stance phase||Ankle instability or foot drop; Extensor tone in pediatric patients,|
|Posterior leaf spring AFO||Allows some medio-lateral ankle movements and provides foot clearance during the swing phase||Dorsiflexion assist|
|Rigid plastic AFO||Limits ankle movements (including limiting medio-lateral control) and assists with ankle control during the swing phase||Severe tone/spasticity when immobilization is needed|
|Articulated/ hinged AFO||Can set to the desired range of ankle dorsiflexion or plantar flexion||For crouched gait, a solid AFO in plantar flexion with dorsiflexion stop can help knee extension during the stance.|
|Off the Shelf Carbon fiber AFO||Light weight, lower profile, can provide dynamic response||Assist with dorsiflexion weakness and give minimal plantarflexion assist|
AFOs with metal upright(s) are less common than plastic AFOs. However, some patients (such as those with morbid obesity or edema) may benefit from a metal AFO.
The construction of a hinged AFO with ankle joints with channels allows for a greater control of gait. The following table explains the ankle joint motion control with pins (stop) or springs.
Permutations for articulated/hinged AFO
|Anterior channel||Posterior channel||Mechanism||Indications|
|Pin/Stop||Free||Dorsiflexion stop. Assists with pre-swing and the knee extension. Anterior stop set at 5 degrees can mimic the function of gastrocnemius/ soleus||Weak ankle plantar flexors and/or weak knee extensors|
|Free||Pin/Stop||A plantar flexion stop at 90 degrees or at neutral produces a flexion moment at the knee during heel strike||Facilitates dorsiflexion moment and provides plantar flexion stop; used for spasticity or plantar flexion contractures|
|Free||Spring||Dorsiflexion assist. Mimics concentric contraction of dorsiflexors. Minimizes plantar flexion at heel strike||Flaccid foot drop|
Knee ankle foot orthoses (KAFOs):
- KAFOs extend the AFO to control the knee. Quadriceps weakness below antigravity strength or knee hyperextension not controlled by an AFO are indications for a KAFO.1
|Type of Knee Joint||Mechanism||Goals/ Indications|
|Straight knee joint||Allows free flexion but prevents knee hyperextension. Can be used with various knee locks for specific indications/functions||Prevents knee hyperextension and provides medial-lateral stability With locking mechanism provides knee extensor/flexor stability|
|Polycentric knee joint||Double axis system, closer approximation of the normal knee kinematics that includes femoral rollback||To allow knee to flex in swing phase|
|Posterior offset knee joint||Allows free flexion and extension of the knee during the swing phase. The center of gravity is posterior to the knee at the heel strike helps creating knee flexion moment||For weak knee extensors and with some hip extensor strengthUse with an ankle joint that is limited in dorsiflexion.3|
In order to stabilize the knee, one of four locks can be used at the knee – cam lock, bail lock, ratchet lock, and drop lock. The most common is the Ratchet lock with 12 degree increments built into the joint. A lever allows for the knee to be released for flexion and to allow sitting.3
Knee orthoses (KO):
- KO provide support or control of the knee joint. KO can limit motion in the sagittal, axial, or coronal planes. Generally KOs are prescribed to prevent knee hyperextension and provide mediolateral stability.4Flexible KOs are made from elastic or rubber, and mostly provide comfort, proprioceptive feedback, mechanical support, and stabilization of patellar tracking.
|Type of Orthosis||Mechanism||Goals/ Indications|
|Flexible KO||Made from flexible material; provides proprioceptive feedback, mechanical support and stabilize patellar tracking||Knee pain Patellofemoral instability|
|Swedish knee cage||Controls knee hyperextension while permits full flexion||Osteoarthritis, genu varus, flexible genu valgum|
|Rigid KO||Provides a frontal plane thrust and unload the affected compartment||Osteoarthritis|
Hip orthoses (HOs):
- HO are indicated for isolated acetabular region problems and are commonly used for post-operative care, hip dislocation, dysplasia, and injury.1 Fracture bypass orthoses also can be used post fracture.
Hip-knee-ankle-foot orthoses (HKAFOs):
- HKAFO are typically used in patients with spinal cord injury to stabilize the entire lower limb in order to stand and walk with assistive devices.
- Reciprocal gait orthoses (RGO) are a type of bilateral HKAFO with a set of cables or a rocker bar linking the legs together to couple hip flexion with opposite side hip extension in order to create a reciprocal gait pattern.1 Successful RGO use requires antigravity hip flexion strength but attainment is limited as they are heavy, bulky, and with high energy expenditure.5
Other lower limb orthoses
- Stretching AFO, KO, and KAFO are dynamic orthoses that can be utilized to improve range of motion by applying a constant, low-load, passive stretch. Static progressive stretch orthoses are set just beyond the current range of motion to improve range of motion or prevent further contractures but compliance can be difficult due to the need for prolonged wearing time.6
- An off the shelf ankle brace with air cell is a semi-rigid shell ankle orthosis with air cells on both sides of the ankle that is worn in a shoe in order to support ankle instability after ankle sprains. It has shown to improve ankle joint function in ankle sprains.7
Foot Orthoses and Therapeutic Footwear
Foot orthoses (FOs)
- FOs are used as the foundation for other lower limb orthoses or can be used alone. FO align and support the foot and prevent, correct, or accommodate foot deformity, or improve the overall function of the foot. FOs are commonly used with therapeutic shoes which should be properly fitted and have adequate room for the foot to expand during weight bearing.1
- Supramalleolar orthoses (SMO) are used primarily in pediatric patients with hypotonia and those with flexible foot pronation.8,9
- Leg length discrepancies less than 2cm without symptoms typically do not require correction. The total leg length discrepancy is never corrected; at most, 75% of the discrepancy should be corrected. Only 1cm lift can fit in a shoe. For shoe lifts that need more than 1cm, the patient would need a custom built shoe with a shoe lift or would need to get an external shoe lift.10
- Both internal and external shoe modifications can be made to the sole or body of the shoe. Heel and internal sole excavation can relieve pain or ulcers over bony prominences. Pad placement provides arch support or relieves pressure; heel and lateral wedges promote appropriate foot positioning or alignment. Bars on the soles of shoes can be placed to assist with weakness, relieve pressure, transfer load, or promote dorsi or plantar flexion.
- Heel flares widen the base and support with different heel material providing cushioning, stability, positioning, and arch support.11
- High top shoes or boots can provide ankle stability in patients with mild ankle instability or mild foot drop, especially in young patients.
3. CUTTING EDGE/UNIQUE CONCEPTS/EMERGING ISSUES
Functional electric stimulation (FES) devices are now used as an alternative to traditional orthoses. These devices generate an electrical current that stimulating a muscle causing muscle contraction in a predictable movement pattern to create physiological bracing. The most common FES device for the lower limb is the FES-AFO which stimulates the tibialis anterior muscle to produce ankle dorsiflexion and eversion.12 These devices have shown moderate gait improvements when compared to traditional AFO. A similar concept has been applied for the upper limb to improve wrist extension. Recent improvements in traditional lower limb orthoses include stance control orthotic knee joints to provide stance-phase stability, while allowing swing-phase flexion. These should permit a more normal gait pattern by eliminating some of the motion restrictions of other orthoses.
Advances in materials, 3-D printing, and robotic exoskeletons are dramatically changing the durability, fabrication time, overall function, and level of assistance provided by orthotic devices. 13
4. GAPS IN KNOWLEDGE/EVIDENCE BASE
The literature supports the use of AFO when stroke or cerebral palsy results in lower limb impairment by demonstrating improved gait, functional mobility, and energy efficiency.2 The effects of orthoses on upper limb function vary based on etiology. The use of static progressive orthoses for the treatment of upper limb joint stiffness or contractures due to an orthopedic cause shows benefits in increased active range of motion, increased grip strength, and reduced need for pain medications during orthotic intervention.6
Despite controversies, orthoses that allow patients to use their paretic limb for functional tasks and a broader range of rehabilitative interventions, generally result in improved limb function and improved quality of life. Patients rely on orthotic intervention as a cost effective and less invasive means to manage common medical conditions such as a valgus knee braces for symptomatic knee osteoarthritis relief.
The cost of orthotic devices varies based on complexity, materials used and fabrication process. To optimize both patient care and utilization of health care resources, it is paramount to have an in-depth knowledge of the patient’s deficits, as well as an understanding of the environmental and personal factors that will influence a patient’s orthoses use. Typical barriers to device utilization include its appearance, weight, and ability to don and doff the orthoses.7 Incorrectly prescribed orthoses may lead to functional impairment and biomechanical derangement which cause medical complications. To limit these obstacles, a team including orthotists, therapists, and physicians must work in concert to maximize patient benefit.
- Webster JB (Joseph B, Murphy D (Douglas P. Atlas of Orthoses and Assistive Devices. https://www.sciencedirect.com/book/9780323483230/atlas-of-orthoses-and-assistive-devices. Accessed August 13, 2019.
- Betancourt JP, Eleeh P, Stark S, Jain NB. Impact of Ankle-Foot Orthosis on Gait efficiency in Ambulatory Children with Cerebral Palsy. Am J Phys Med Rehabil. March 2019:1. doi:10.1097/PHM.0000000000001185
- Frontera WR. DeLisa’s Physical Medicine and Rehabilitation: Principles and Practice: Fifth Edition.; 2012.
- Khosravi M, Arazpour M, Sharafat Vaziri A. An evaluation of the use of a lateral wedged insole and a valgus knee brace in combination in subjects with medial compartment knee osteoarthritis (OA). Assist Technol. April 2019:1-8. doi:10.1080/10400435.2019.1595788
- Karimi MT, Fatoye F. Evaluation of the performance of paraplegic subjects during walking with a new design of reciprocal gait orthosis. Disabil Rehabil Assist Technol. 2016;11(1):72-79. doi:10.3109/17483107.2014.921247
- Costa CR, McElroy MJ, Johnson AJ, Lamm BM, Mont MA. Use of a static progressive stretch orthosis to treat post-traumatic ankle stiffness. BMC Res Notes. 2012;5:348. doi:10.1186/1756-0500-5-348
- Boyce SH, Quigley MA, Campbell S. Management of ankle sprains: A randomised controlled trial of the treatment of inversion injuries using an elastic support bandage or an aircast ankle brace. Br J Sports Med. 2005. doi:10.1136/bjsm.2003.009233
- Davids JR, Rowan F, Davis RB. Indications for orthoses to improve gait in children with cerebral palsy. J Am Acad Orthop Surg. 2007. doi:10.5435/00124635-200703000-00008
- Martin K. Effects of supramalleolar orthoses on postural stability in children with Down syndrome. Dev Med Child Neurol. 2004. doi:10.1017/S0012162204000659
- Cifu DX. Braddom’s Physical Medicine & Rehabilitation. Fifth. Philadelphia, PA: Elsevier; 2016. https://www.clinicalkey.com/dura/browse/bookChapter/3-s2.0-C20130099252.
- Buldt AK, Menz HB. Incorrectly fitted footwear, foot pain and foot disorders: a systematic search and narrative review of the literature. J Foot Ankle Res. 2018;11:43. doi:10.1186/s13047-018-0284-z
- Prenton S, Hollands K, Kenney L, Onmanee P. Functional electrical stimulation and ankle foot orthoses provide equivalent therapeutic effects on foot drop: A meta-analysis providing direction for future research. J Rehabil Med. 2018;50(2):129-139. doi:10.2340/16501977-2289
- Ford C, Grotz R, Kope Shamp J. The Neurophysiological Ankle-Foot Orthosis. Clin Prosthes Orthot. 1986;10:15-23.
Original Version of the Topic
Marlis Gonzalez-Fernandez, MD, PhD, David Taftian, MD, Mark Hopkins, PT, CPO. Upper and lower limb orthoses and therapeutic footwear. Original Publication Date: 9/20/2014
Mi Ran Shin, MD
Nothing to Disclose
Olga Morozova, MD
Nothing to Disclose
Jeffery Rubin, DO