Introduction to Spinal Orthotics

Original Editor - Carin Hunter based on the course by Donna Fisher
Top Contributors - Robin Tacchetti, Carin Hunter, Jess Bell, Kim Jackson and Tarina van der Stockt

Introduction

• Orthotic management of spinal disorders dates back to Egyptian times.
• Some of the concepts used in primitive devices, such as the use of three-point forces are still valid today.
• Materials have progressed from metal and leather to light weight foams and thermoplastics facilitating new designs and more comfort for the user.

• Spine is a complex part of our anatomy and the key structure to our function.
• Not possible to treat all spinal issues with orthotic and team work with surgeons, physiotherapy and the patient is important
• Assessment, goal setting and clear expectations will lead to a well designed and appropriate orthotic device which is comfortable and functional and meets the users needs.

What is an orthosis

• External aid
• The word orthosis is derived from the Greek word meaning “to straighten or align”
• Spinal orthoses or braces are appliances used to correct and support the spine
• Integrates biomechanical principles
• OTS/Individually designed/customised
• Unlike most other types of orthoses, many spinal braces are OTS

Why a spinal orthosis

• Provides support and stabilization
• Maintains alignment of spine
• Prevention/correction of deformity
• Reduce pain by limiting motion
• Assist with healing post surgery

Principles of Spinal Bracing

Design of a spinal brace is based on:

• Biomechanics of the spine
• Restriction of motion
  • sagittal
  • coronal/frontal
  • transverse or combination of directional control
• Reduction of axial loading of the spine
• Increasing intra-abdominal pressure may reduce axial loading of spine
• May provide heat and kinesthetic feedback, acts as a reminder.

Principles - 3 Point Pressure Control

Based on “Laws of Equilibrium”

• Most orthotic devices use a three-point pressure control design
• This requires three-points of contact with balanced opposing forces in a particular plane.
  • Pressure = Force / Area
  • Moment = Force x Distance
  • Moment is angular movement around an axis. The longer the lever arm the less force is required to control a joint and therefore results in reduced pressure

Design/Manufacture

• Materials – soft fabric, flexible plastic, polyethylene, rigid plastic polypropylene
• Construction – OTS or Custom made
• Suspension/strapping- above iliac crests, over shoulders
• Cosmesis – worn under clothing around trunk

Fitting and Evaluation

• Comfortable to wear – most important in spinal bracing as applying high forces and rejection is common.
• Good anatomical fit
• Good biomechanical function – may require in/out of brace x-rays to determine function.
• Easy to don/doff
• Cosmesis

Anatomy

• The vertebral column consists of 24 individual bones called vertebrae.
• The spinal column consists of this vertebral column and 2 sections of naturally fused vertebrae—the sacrum and the coccyx—located at the very bottom of the spine.
• 
  The vertebral column can be divided into 5 regions:
  • Cervical spine: 7 vertebrae of the neck (C1-C7)
  • Thoracic spine: 12 vertebrae of the mid-back (T1-T12)
  • Lumbar spine: 5 vertebrae of the lower back (L1-L5)
  • Sacrum
  • Coccyx
  • Separated by Discs, intravertebral discs, fluid filled cushions between vertebrae

Function/movements of each region

Cervical

• There are 7 cervical vertebrae with 2 considered atypical vertebrae:
• Atlas and Axis
• Cervical flexion/Extension – Atlas (Nodding)
• Cervical Rotation –Shaking head Axis
• Lateral bending

Thoracic Region

• There are 12 thoracic vertebrae
• The thoracic vertebral motion is limited by the facets and ribs
  • Rotation
  • Flexion/extension
  • Side /Lateral bending
• Largest motion is at T12/L1. Due to the lack of rib stabilization at this level and the facets being more medial to lateral orientation
• Associated with more injury and degenerative changes.

Lumbar Region

• There are 5 lumbar vertebrae:
  • Primarily flexion and extension,
  • Some lateral bending
  • Limited rotation

Anatomy of Spine - Problems

• Spine function
• Upright walking, protection spinal cord, head to ground weight transfer
• Ligaments muscles
• Discs, intravertebral discs
• Bony structures attached

Common spinal disorders

• Fractures-
  • Compression
  • Dislocation
  • Compression/dislocation
  • 5-10% occur in the cervical (neck) region.
  • 60-65% occur in the thoracolumbar (low back) region, often at T12-L1.
    • Common Causes: Osteoporosis, Trauma, Tumour

• Intravertebral disc problems

• Prolapsed/ herniated disc
• Degeneration
• Age, trauma, repetitive strain, wear and tear.
  • Spondylolisthesis-  Latin term meaning slipped vertebral body Typically, the L4 vertebral body slips forward on the L5 vertebral body. Under normal circumstances, the L4-L5 segment is the one in the lumbar spine with the most movement.
  • Spondylolisthesis in the lumbar spine is most commonly caused by degenerative spinal disease (degenerative spondylolisthesis).
  • occurs as a result of due to degeneration or wear and tear of the intervertebral discs and ligaments.
  • Osteoarthritis of the facet joints can also play an important role in the development of instability and slippage.
  • Degenerative spondylolisthesis usually occurs in people over 60 years of age.
    • Curvatures
    • Lordosis. Excessive convex curvature of the lumbar spine
    • Kyphosis. Kyphosis is characterized by concave curvature of the upper spine (abnormal > 50 degrees of curvature)
    • Scoliosis. A lateral bend in the spine. The curve can be S-shaped or C-shaped. Causes vary: congenital, degenerative, trauma, tumour and idiopathic in nature
    • Soft tissue injuries Soft tissues include the muscles, tendons, ligaments, and nerves. Injury to these tissues can be caused by unnecessary stress to the spine
    • Sprains/strains- lifting, poor posture
    • Muscle injury – lifting, sports
    • Trauma - Whiplash
    • Whether we are designing a custom made or customised device or fitting an off the shelf device. The construction of the orthosis is based on the assessment of the patient and clear goals of what we want to achieve. The material choices should reflect the forces to be generated and where, the activity level of the user and the proposed use of the orthosis and the environment. Often the orthosis will be a multi-layered construction, using different materials. Any suspension or strapping is an integral part of the design and should be based on the users ability to don/doff the device, the area of the body to be braced and skin and pressure considerations. The cosmesis or how the device will ultimately look is also very important, often we can be focused so much on the function of a device that we can overlook the importance of providing a comfortable and aesthetically pleasing orthosis. This can be a show stopper for some users and they can choose to abandon an orthosis that functions well but just doesn’t look good!

Orthotic Prescription

• Medical and social history, underlying condition, x rays, diagnostics
• Diagnosis of problem, knowledge of anatomy/physiology
• Functional goals of the orthotic device:

Need to determine what motions should be restricted by the device: sagittal, frontal, transverse plane motion

• Materials and design
• Needs of the user

Types of Spinal Orthoses

1. CO:  Cervical orthosis (collars)
2. CTO: Cervicothoracic Orthosis (HALO, SOMI, Minerva)
3. CTLSO: Cervico-thoraco-lumbosacral Orthosis (Milwaukee)
4. TLSO: Thoracolumbo sacral orthosis CASH, Jewett, custom TLSO
5. LSO: Lumbosacral orthosis (Corsets, Chairback O)
6. SO: Sacral orthosis ( Sacro-iliac bands)

1. Cervical orthosis (CO)

1. Soft Collars

• Soft cervical collar: construction foam

• Provides partial support of the head reducing paraspinal contraction and spasm. No structural cervical spine support.
• Movement
  • Flexion/extension by ~ 8-26%,
  • Lateral bending is limited by ~8%
  • Rotation ~10-17%.

• Muscular strains/sprains
• Trauma

Acts as a reminder, psychological reassurance and can provide relief through heat retention

2. Hard Collars

• Miami J Collar/VISTA Collar/ Aspen/ headmaster/Philadelphia
  • (Rigid/semirigid): It is made of hard foam combined with plastic
  • Supportive
• Movement/function
  • Flexion/extension limited ~69-90%,
  • lateral bending limited ~34-48%
  • Rotation limited ~74%.
• Features

• Has tracheostomy opening
• Custom adjustment height around chin and occiput
• Less sweating, more comfortable
  • Indications
  • Cervical trauma in unconscious patients
  • Jefferson’s Fracture (C1) Hangman’s fracture
  • Traumatic spondylolisthesis of C2 on C3
  • Dens type I fracture
  • Post op care
  • Anterior discectomy
  • Cervical Strain

2. Cervicothoracic Orthosis (CTO)

1. Halo
2. Sterno-occipital mandibular orthosis (SOMI)
3. Minerva

CTO

• Halo- extensive brace, surgically applied
• 4-poster orthotic that is attached by pins that are placed in the cranial table. Jacket fitted to torso.
• Maximum motion control to T3
  • Flexion/Ext limited 96%
  • Lateral Bending limited 96%
  • Rotation limited 99%.

1. Halo

• Indications:
  • Occipital condyle fractures
  • C1 ring injuries,
  • Odontoid fractures
  • Hangman fractures (C2)
  • facet subluxations
  • spinal infections
  • Extradural tumor involvement that compromises the spinal alignment or bony stability
  • Subaxial spine injuries

2. Sterno-occipital mandibular Orthosis (SOMI)

• 3-Poster CTO

Anterior chest plate that extends to the xiphoid process. It has a removeable chin strap.

• Motion restriction
  • Flexion/Extension is limited ~60-70%
  • lateral bending ~20-35%
  • rotation is limited ~30-65%

Controls flexion of C1-3 but controls extension less than with other cervical orthotics.

• Indications
  • Atlanto-axial instability such as in Rheumatoid Arthritis
  • Neural arch fractures of C2 due to flexion instability

3. Minerva

• Minerva –removable version of HALO Compliant patient who will not just remove it.
• Motion control
  • Flexion/Ext limited 96%
  • Lateral Bending limited 96%
  • Rotation limited 99%. Controls motion down to T3.
• Indications
  • mid-to-lower cervical spine injuries and
  • stable upper cervical spine injuries.
  • Can be used with skull fractures-Halo Fixator is contraindicated
  • Children due to its decreased weight and increased comfort.

3. Cervico-thoracolumbarsacral Orthosis (CTLSO)

• Milwaukee Brace- the classic CTLSO

• Metal vertical superstructure with pelvic foundation with rigid plastic pelvic girdle connected to the neck with a ring. There are two posterior paraspinal bars. The cervical ring has mandibular and occipital bars that rest 20-30 mm inferior to the chin.

• Indications

• For treatment of kyphosis, high thoracic curves

occiput and mandible.

Pads are positioned to apply forces to correct curvature.

4. Thoracolumosacral Orthosis (TLSO)

• TLSO: Thoracolumbar orthosis
• CASH, Jewett, Custom-molded body jacket. Knight Taylor TLSO
• Providence Night Brace
• Charleston Bending Brace

OTS- adapted for individual use or Custom made

• OTS TLSO - comfortable design, easy to don and doff.
  • CASH, Jewett, Knight Taylor TLSO
  • limited movement control
  • flexion from T6 -L1.
  • does not limit lateral bending or rotation.

Indications:

• Thoracic and lumbar vertebral body fracture and kyphosis reduction in osteoporosis.

• Moulded plastic Spinal Jacket (TLSO)
  • OTS shell
  • Custom made – from plaster cast
    • Overlap type brace Indications:
    • Immobilization for thoracic compression fractures from osteoporosis. Immobilization after surgical stabilization for spinal fractures.
    • Immobilization for unstable spinal disorders of T3-L3.
    • Custom made Spinal Jacket (TLSO)
      • Custom made – from plaster cast
      • Scoliosis, severe spinal abnormailities
      • Night Bracing

SCOLIOSIS

• Neuromuscular Scoliosis

• Congenital Skeletal Scoliosis

• Idiopathic Scoliosis
• Indications for Bracing in Scoliosis
• • Flexible curves with Cobb angle(10°- 40°) • 10°- 20° observe initially, if curve progresses by 5° then brace • 30°- 40° prompt use of orthosis • > 40◦  generally surgery • Risser sign for remaining growth
• Boston Brace
  • 1970’s, most Research and widely used
  • Module from measures, type of curve
  • Blueprint created from x rays
  • Determine apex of curve and position of pads (3 point pressure)
  • Cut outs to allow body to move
  • Difficult to control rotation
  • Maximum curve 45 degrees below T8
  • Cheneau Brace
    • Relatively new type, limited research but possibly better results due to rotational control
    • Fully custom made
    • Type of curve, assessment, x rays
    • Pads and cut outs, severe looking
    • Control rotation with extensions at shoulders
    • Prescription criteria for Neuromuscular Scoliosis
      • Generally not Boston or Cheneau
      • Different etiology, muscle weakness, underlying condition, severity
      • Corrects flexible curves
      • Provides stability
      • Accommodates fixed deformities
      • Can prevent further deformity

5. Lumbo-sacral Orthosis (LSO)

• Fabric lumbar support – soft fabric support often with metal or plastic struts to provide support for lumbar region of spine

Indications: Pain relief, postural support, reduces excessive lumbar lordosis, vasomotor and respiratory support in the spinal cord patient. Increase intra abdominal pressure, heat, kinesthetic feedback

• Moulded plastic Spinal Jacket (LSO)
  • OTS- adapted for individual use
  • Custom made – from plaster cast

6. Sacral Orthosis (SO)

• Fabric support- Sacro-iliac band support
• Sacrio-iliac joint pain

References

Weiss, Hans-Rudolf, Stefano Negrini, Manuel Rigo, Tomasz Kotwicki, Martha C. Hawes, Theodoros B. Grivas, Toru Maruyama, and Franz Landauer.

"Indications for conservative management of scoliosis (guidelines)."

Scoliosis 1, no. 1 (2006): 5.

Giele BM, Wiertsema SH, Beelen A, van der Schaaf M, Lucas C, Been HD, Bramer JA. No evidence for the effectiveness of bracing in patients with thoracolumbar fractures: a systematic review. Acta orthopaedica. 2009 Jan 1;80(2):226-32.

van Leeuwen PJ, Bos RP, Derksen JC, de Vries J. Assessment of spinal movement reduction by thoraco-lumbar-sacral orthoses. Journal of rehabilitation research and development. 2000 Jul 1;37(4):395.

Kawchuck, Gregory; A non-randomized clinical trial to assess the impact of nonrigid, inelastic corsets on spine function in low back pain participants and asymptomatic controls, The spine Journal 15 2015 pg 2222-2227

Harrington, Amanda: Chapter 43, Spinal Orthoses; Spinal Cord Medicine 2019 Springer Publishing Company, Editor Steven Kirshblum MD pg 744- 753

Schott, Cordelia: Effectiveness of lumbar orthoses in low back pain: Review of the literature and our results. Orthopedic Reviews 2018 Vol 10, 7791 pg 141-146

Morris: Role of the trunk in stability of the spine JBJS, 1961;43:327-351 36.

Nachemson: In Vivo Measurements of intradiscal pressure: Discometry, a method for the determination of pressure in the lower lumbar discs, JBJS American Volume 46(5) 1964 pg 1077 to 1092

Lantz SA, Schultz AB: Lumbar spine orthoses wearing: Effect on trunk muscle myoelectric activity. Spine 1986;11:838–4234. 29.

Lantz, S: Lumbar Spine Orthosis Wearing II. Effect on Trunk Muscle Myoelectric Activity Spine Vol 11, Number 8 1986 pg 838-842