This document discusses the key determinants for ascending stairs, including:
1. Lower extremity force production from muscles like the quadriceps and hip extensors is needed to move the center of mass over the base of support.
2. Dynamic postural stability during single limb stance is required for balance.
3. Lower extremity coordination of simultaneous hip and knee movement advances the center of mass.
4. Proper alignment of the torso, hip, knee and ankle is important.
5. Sufficient range of motion at the hip, knee and ankle is necessary to complete the stair ascent task.
2. Cycle Defined By:
• Initiation:
• Toe off of first step
• Termination:
• Ipsilateral foot toe off
of second step
(Looking at the R leg)
3. Stability
Coordination
Force Production
Alignment
Speed
Center of Mass
Base of Support
Control
Maintenance
Foot
placement
Transition
Symmetry
Body position
Balance
Our Process
1. LE Force Production
2. Dynamic Postural Stability
3. LE Coordination
4. Alignment
5. Range of Motion
4. Force Production
• Contraction of muscles that allow the center of mass to be moved
over the base of support in a superior and anterior direction
• Most important muscles needed for the production of force that
allows execution of task:
• Quadriceps
• Hip Extensors
• Ankle Dorsiflexors
5. Force Production
• Mcclelland et. al.
• Proper force production of the quadriceps is
needed for proper stair accent
• They measured the knee flexion and extension
moments and compared control group with
patients post TKA.
• All participants generated a knee flexion moment
that changed direction to an extension moment
during stair ascent
• Patients post TKA with decreased quadriceps strength
reduced flexion moment and an earlier change in
moment direction from flexion to to compensate
for decreased quadriceps strength.
When force production of quadriceps is absent,
this results in abnormal stair climb patterns and
compensations.
6. Force Production
• Tiedemann et al.
• Linear relationship between
strength of hip and knee extensors
and ankle dorsiflexors and speed
• Gender and age correlation with
strength
7. Dynamic Postural Stability
• Single limb stance
• Postural Stability: maintenance of center of mass within the base of
support
• Postural Orientation
Motor Control
Postural OrientationPostural Stability
8. Dynamic Postural Stability
• Anterior-Posterior Axis
• Maintain COM within BOS, lateral
direction
• Butler et al.
• Hand rail use
• 52% older adults
9. Dynamic Postural Stability
• General Postural Stability
• Proprioception and sensory
information
• Hurley, M.V. et al.
• Combination of
proprioception, strength and
integration of sensory
information
11. LE Coordination
• Lin et al.
• Stance phase
• Greater required peak moments at
the knee and ankle joints (first
half)
• Hip extension moment present
throughout the entire stance
phase.
This coordination of simultaneous hip and knee extension is critical in
transferring momentum of body up the stair.
13. Alignment
• Position of adjacent body segments in relation to each other
• Stairs:
• Torso
• Hip
• Knee
• Ankle
14. Alignment
• Saari et. al.
• Patients with knee osteoarthritis patients with knee OA also had knee
instability.
• Joint laxity and excessive motion leads to instability during dynamic and
functional activities such as stair climbing.
• Inability to control motion in the sagittal plane during stair accent and
difficulty completing the task of stair climbing correctly.
16. Range of Motion
• Hip
• Extension to Flexion: 1-0-66˚
• Knee
• Flexion: 93-105˚
• Extension: 0˚ (ideally)
• Ankle
• DF to PF: 20-0-30˚
17. Range of Motion
• Knee
• Mean flexion: 83-105˚
• Dependent on height of
person and stair
18. Range of Motion
• Hip
• Torque angle profiles of the hip extensor muscles
19. Conclusion
1. LE Force Production
2. Dynamic Postural Stability
3. LE Coordination
4. Alignment
5. Range of Motion
Editor's Notes
Add video slow mo
Mcclelland et. al. determined that proper force production of the quadriceps is needed for proper stair accent. They measured the knee flexion and extension moments and compared control group with patients post TKA. All participants generated a knee flexion moment that changed direction to an extension moment during stair ascent. However, for patients post TKA who presented with decreased quadriceps strength, the moment pattern was characterised by a reduction in the magnitude of the flexion moment and a change in moment direction from flexion to extension that occurred earlier in the step cycle to compensate for decreased quadriceps strength. When force production of quadriceps is absent, this results in abnormal stair climb patterns and compensations as measured in the study by Mcclelland et. al.
Age 75-98 – community dwelling adults
8 stairs. Allowed to use the hand rail and gait aid if they desired
Gender difference : 4.8 +/- 2.2 men ; 6.0 +/- 3.4 women
Moderate correlated with age
Postural Orientation
50 participants 20-39yrs
684 participants 75-98yrs
Only one of the younger participants used the rail while ascending the stairs while 52% of the older adult population used the rail. This instability could be the result of sensorimotor deficits that come with age. It could also be secondary to a lack of strength causing the instability. Regardless of the source, this supports the fact that stability in the A/P axis is required in order to ascend stairs.
Hurley MV et al found that the increase in time it takes older patients to ascend a flight is due not only to strength but also to proprioception and sensory information which together make up postural stability. All of these things add together to decrease confidence which cause longer times for older people when going up a flight of stairs. Since these factors affected stair ascention times, we can conclude that postural stability, which includes sensory and proprioception information are required to ascend stairs. When these factors are impaired, the person has difficulty and takes longer to go up the stairs.
During ascending and forward motion of the body from one step to the next step, hip extension and knee extension during the execution phase of the task occur simultaneously to allow for advancement of center of mass.
In a study by Lin et al. Stair required greater peak moments at the knee and ankle joints in the first half of the stance phase. During stair ascent a hip extension moment was present throughout the stance phase. This coordination of hip and knee extension simultaneously is critical in transferring momentum of body up the stair.
videos
In a study by Saari et. al. looking at patients with knee osteoarthritis patients with knee OA also had knee instability. Joint laxity and excessive motion leads to instability during dynamic and functional activities such as stair climbing. People with knee instability will not be able to control the motion in the sagittal plane during stair accent and have difficulty completing the task correctly.
Foot placement on the step is also important factor to allow for proper alignment during stair accent. The placement of the entire foot on the step is important for allowing for the ankle, knee and hip to align above in to support the COM over the narrow BOS.
Protopapadaki et al. looked at the kinematics of stair ascention and descention in young healthy adults. The maximal ranges stated here occurred during the swing phase of stair climbing. The necessary range of motion varies greatly but the study concluded that large ranges of ankle motion were not as important when compared to knee and hip ranges.
The data was collected for a stair height of 18cm and a tread length of 28.5cm which is important because the stair height can change the necessary angles produced by the body. The maximal knee flexion occurs during swing phase which is represented here as the section after 60%. This is necessary in order to clear the previous step and to place the foot on the next step.
The majority of the hip range of motion is in flexion, the majority of the moment is into extension. You can also see in the ROM graph that the hip does not usually need to go past neutral in order to ascend the stairs. This is different than walking where the hip needs to go into at least 10 degrees of extension to have a normal pattern.