The HKAFO and RGO

HKAFO

• components used to stabilize or lock hip, knee, and ankle
• Unilateral
• Bilateral = B KAFOs linked above the hip with pelvic band, LSO, or TLSO
• Hip section = transverse and sagittal plane stability
• blocks hip abduction, adduction, rotation
• when hinge locked - blocks hip flex/ex

Types of HKAFOs

including uses and indications

References

HKAFO

THKAFO

• pt's with paraplegia (spina bifida)
• bilateral uprights or unilateral uprights

• rigid
• adults and children with paraplegia
• solid AFOs with thigh shells + lateral uprights
• allows pt to stand upright and stable
• must have BUE use to assist
• parallel bars or crutches
• swing-to or swing-through gait

Bowker P, et al. Biochemical Basis of Orthotic Management. 1993

Edelstein JE, Bruckner J. Orthotics: A Comprehensive Clinical Approach. 2002

Hsu JD. AAOS: Atlas of Orthoses and Assistive Devices. 2008.

Bowker P, et al. Energetics of paraplegic walking. J. Biomed Eng; Vol 14; July 1992.

Harvey LA, et al. Functional outcomes attained by T9-T12 paraplegic patients with the Walkabout and the Isocentric Reciprocal Gait Orthosis. Archives of PMR; Vol 78, July 1997

Harvey LA, et al. Energy expenditure during gait using the Walkabout and Isocentric Reciprocal Gait Orthosis in persons with paraplegia. Archives of PMH; Vol 79, 1998.

Winchester PK, et al. A comparison of paraplegic gait performance using two types of reciprocating gait orthoses. Prosthetics and Orthotics Intl; 17, 1993.

Objectives

• Uses and indications for hip orthoses, such as the Newport Orthosis
• Components of the HKAFO
• Types of HKAFOs, uses, and indications
• RGO uses, indications, biomechanics, fitting, energy consumption, compliance, and literature.
• RGO v Walkabout

RGO

Uses and Indications

• ambulation with 2 or 4 point gait with crutches
• paraplegics (adults and children)
• Invented at the Ontario Crippled Children's Centre
• Design refined at LSU

Hip Orthoses

Components

• Pair of KAFOs
• anterior leg and thigh straps
• hip/pelvic band
• uprights that terminate at rigid dorsal band
• anterior thoracic strap
• steel cable that joins the hip joints

Biomechanics

• Components
• Reciprocal gait

Achieving Reciprocal Gait

• Shifting Body weight forward and laterally, while extending hips and upper back.
• Hip extension of weighted leg allows orthosis mechanism to advance unweighted leg.

• Used for isolated problems of the acetabulum
• dysplastic DO of the hip
• traumatic injury
• surgical procedures (THA)

• articulated THKAFO
• Uses/Indications
• Biomechanics
• Fitting
• Energy Consumption
• Compliance
• Literature

Fitting an RGO

• expectations and motivations of patient
• goals of patient
• Examination
• level of injury
• scoliosis? pelvic obliquity? contractures? hip instability? spasticity? hx of fxs?
• hip flexion contracture > 30° and/or knee contracture > 20° that is uncompensated will limit upright standing ability
• ankle plantar flexion contracture up to 15° can be compensated with a wedge
• orthostasis - tilt table prior to RGO

Sagittal Plane

Transverse Plane

Newport Orthosis

• connecting legs of orthosis
• hip sections linked with pelvic band
• pts with hip obliquity (scoliosis/subluxation of hip)
• these pts have difficulty maintaining parallel alignment of lower limbs and will benefit from connected hip section.

• Foot
• custom molded, in shoe
• adequate arch support
• Ankles
• custom molded solid AFO
• adjustable ankle joints
• Knee
• ring type drop lock or step lock
• Hip
• sagittal stability for those with hip flexion contractures
• Trunk stability with TLSO for hip orthosis/HKAFO
• Trunk section for engaging reciprocating mechanism in stance.

Literature

Used to maintain hip within safe ROM

• Energy Cost
• Physiologic Cost Index
• (Walking HR - Resting HR)/walking speed
• Normal Ambulation 0.11-0.51 beats/meter
• O2 consumption
• normal ~12.0 mL/kg·min
• Compliance
• Studies show pt prefer RGO over HGO due to improved appearance and stability while standing.
• HGOs were easier to don/doff

Walkabout Orthosis

• 2 KAFOs joined by single axis hip joint called Walkabout unit.
• restricts mediolateral and rotational movement of hip
• hip joint ensures leg only swings in anteriolateral plane
• Advantages
• no thoracolumbar corset like in RGO
• lighter
• less expensive than RGO

The hkafo and RGO