Evidence for the Benefits of Microprocessor Controlled Prosthetic … · 2020-04-28 · Bellmann M, Schmalz T, Blumentritt S: Comparative biomechanical analysis of current microprocessor

Evidence for the Benefits of

Microprocessor Controlled Prosthetic Knees

Andreas Kannenberg, MD PhD, Executive Medical Director North America

| © Otto Bock HealthCareAndreas Kannenberg – Baltimore, MD - March 28, 2012 2

Passive microprocessor-controlled prosthetic knees

Genium / X3 C-Leg (4) / C-Leg Compact

(Ottobock, Germany)

Rheo Knee(Össur, Iceland)

Orion (Endolite, UK)

Plié (Freedom

Innovations, USA)


Different principles of the passive MPKs (1)

Default stance• Genium / X3• C-Leg / C-Leg Compact• Kenevo• Orion• Plié

Default swing• Rheo Knee

Always in stance resistance, unless switched into swing.

Always in swing resistance, unless switched into stance.

1Lusardi M.M., Jorge, M., Nielsen C. (2012) Orthotics and prosthetics in rehabilitation 3rd Edition. Elsevier Health Sciences.

“Whether a stumble or fall will result from an unexpected step onto a flexed knee depends greatly on the MPK default setting. MPKs with swing phase knee resistance default settings require great compensatory movements; otherwise, falls occur even in younger people whose amputation etiologies were nondysvascular.”1

“Whether a stumble or fall will result from an unexpected step onto a flexed knee depends greatly on the MPK default setting. MPKs with swing phase knee resistance default settings require great compensatory movements; otherwise, falls occur even in younger people whose amputation etiologies were nondysvascular.”1


Different principles of the passive MPKs (2)

Separate simultaneous control of flexion and extension resistance• Genium / X3• C-Leg / C-Leg Compact• Kenevo• Orion

One resistance only for both flexion and extension at a time• Rheo Knee• Plié

High stance flexion resistance for stumble recovery during low extension resistance for swing.

Needs to switch into stance first in case of a stumble to provide high flexion resistance.

!!! SAFETY !!!


Different principles of the MPKs (3)

MP stance and swing control• Genium / X3• C-Leg• Rheo Knee• Orion

MP stance control• C-Leg Compact• Kenevo

MP switch, but non-MP stance and swing control• Plié


English language publications on different MPKs

0

10

20

30

40

50

60

C-Leg / C-Leg Compact Genium/X2 Rheo Knee Orion Plié

49

10

51 1


Safety of the C-Leg:

Wetz HH et al., Orthopäde 2005, 34: 298-319Johansson JL et al., Am J Phys Med Rehabil 2005, 84: 563-575Chin T et al., POI 2006, 30(1): 73-80Segal AD et al., JRRD 2006, 43: 857-870Hafner BJ et al., Arch Phys Med Rehabil 2007, 88: 207-217Kaufman KR et al., Gait & Posture 2007, 26: 489-493Schmalz T et al., Gait & Posture 2007, 25: 267-278Kahle JT et al., JRRD 2008, 45: 1-14Drerup B et al., Orthopädie-Technik 2008, 3: 169-174Blumentritt S et al., J Prosthet Orthot 2009, 21 (1): 2-15Hafner BJ et al., JRRD 2009, 46 (3): 417-434Bellmann M et al., Arch Phys Med Rehabil 2010, 91 (4): 644-652Blumentritt, S et al., Orthopädie-Technik 2010, 11: 788-799Highsmith MJ et al., Prosthet Orthot Int 2010, 34 (4): 362-377

Less stumbles and falls, improved balance


Systematic Review of C-leg Research

18 studies comparing the C-leg to mechanical prosthetic knees were reviewed

7 studies on safety

8 studies on energy efficiency

3 studies on cost-effectiveness (Sweden, Italy, Netherlands)

methodologic quality of the safety and energy efficiency studies was rated low to moderate

methodological quality of the cost-effectiveness studies was rated high

Highsmith MJ, Kahle JT, Bongiorni DR, Sutton BS, Groer S, Kaufman KR: Safety, energy efficiency, and cost efficacy of the C-leg for transfemoral amputees: A review of the literature. Prosth Orthot Int 2010, 34 (4): 362-377


Safety – Summary of the systematic review

“Five of these seven studies provide consistent, statistically significant findings of improvements in self-reported reduction of stumbles and falls and improved balance. Additional non-statistically significant improvements support the latter findings and include knee stability in conditions resulting in collapse of other knees and improved balance confidence.“

“In total, these seven studies provide a grade “B“ recommendation.“

Highsmith MJ, Kahle JT, Bongiorni DR, Sutton BS, Groer S, Kaufman KR: Safety, energy efficiency, and cost efficacy of the C-leg for transfemoral amputees: A review of the literature. Prosth Orthot Int 2010, 34 (4): 362-377


Blumentritt S et al., 2009

Blumentritt S, Schmalz T, Jarasch R: The safety of C-leg: Biomechanical Tests. JPO 2009, 21 (1): 2-15

Study design

Biomechanical study comparing the safety of the C-leg, 3R80, and Mauch SNS (3C1) in repeated challenges in three experienced TF amputees (2 K4, 1 K3)

Tested challenges:

sudden stop on the prosthetic side

sidestepping on the prosthetic side

stepping onto an obstacle (under the heel, midfoot, forefoot)

tripping (interruption of knee extension during terminal swing)


Sudden stop on the prosthetic leg

Sudden stop on the prosthetic side

Sudden stop on the prosthetic side

with step to the side

safe C-leg safe

safe Hybrid safe

compensatory movements Rheo compensatory movements

incidental knee collapse Adaptive incidental knee collapse

Bellmann M, Schmalz T, Blumentritt S: Comparative biomechanical analysis of current microprocessor controlled prosthetic knee joints. Arch Phys Med Rehabil 2010, 91: 644-652.


Sudden stop on the prosthetic leg (C-Leg)

Courtesy Micheal Leach, Otto Bock USA


Tripping…


…caused by a rapid tug on a thin cord attached to the prosthetic foot to interrupt swing extension at different knee angles.


Tripping


Hybrid Knee C-leg


Tripping at different knee angles


• no problems

• heavy compensation

• fall

Zug Kontakt Prob. Zug Kontakt Prob. Zug Kontakt Prob. Zug Kontakt Prob.

[°] [°] # [°] [°] # [°] [°] # [°] [°] #

13 0 7 15 11 6 15 9 415 10 516 10 716 13 5

20 9 6 18 8 8

24 10 2 29 10 2 21 16 4 21 17 7

26 4 3 23 11 1 26 15 128 4 3 25 20 3 27 25 8

28 19 831 12 8 31 22 3 30 20 4 30 25 4

33 9 1 31 22 5 32 28 2 34 19 433 19 3 33 25 435 14 1 34 28 6

36 18 5 36 25 8 38 26 739 29 4 36 30 842 27 4 37 17 443 14 2 39 36 6

45 34 8 40 25 148 26 6 47 15 7 42 40 2 43 37 749 27 1 48 30 1 44 33 7 45 37 749 29 7 50 25 8 45 35 3 45 37 850 34 7 52 37 6 48 20 1 52 32 1

53 26 1 54 26 8 50 33 7

Adaptive2

10

° - 20

°

Knieflexionswinkel bei Störung

C-Leg Synergy Rheo

21

° - 35

°3

5° - 5

5°

knee flexion angle at pertubation Maximum “knee pertubation angle“ that can be compensated by the different MP knees:

C-leg 35°

Rheo 30°Hybrid 30°

Adaptive 20°Mauch SNS/Ca-Tech 20°

other mechanical knees 10°

C-leg Hybrid Rheo Adaptive

| © Otto Bock HealthCareAndreas Kannenberg – Baltimore, MD - March 28, 2012

Safety outcomes in the K2 population

16

Study Kahle et al. (2008) Hafner et al. (2009) Burnfield et al. (2012)

Safety related outcome

measures

Number of stumbles and falls VAS on number and frequency of

stumbles and falls, confidence

while walking and frustration with

falls

Timed up and go test (TUG),

Activity-specific Balance

Confidence Scale (ABC scale)

Results with statistical

significance (p<0.05) in

favor of the MPK

Number of falls decreased 81%

from 2.1±1.5 to 0.4±0.7

(p=0.05)*.

Stumble frequency decreased

15.8% (p=0.05).

Number of falls decreased 80%

(p=0.01).

Falls frequency decreased

4.5% (p=0.01).

TUG decreased 28% from 24.5 s

to 17.7 s (p=0.018).

Balance (ABC) improved 26%

from 60.1 to 75.7 (p=0.001).


trend (p<0.10) in favor of

the MPK

none

Confidence while walking

improved 12% (p=0.08).

Frustration with falls

decreased 23.4% (p=0.06).

none

No statistical difference

between MPK and NMPK

Number of stumbles

Embarrassment with falls

Number of stumbles

Frequency and number of

semicontrolled falls

none


significance (p<0.05) or

trend (p<.10) in favor of

the NMPKs

none none none

*post-hoc statistical analysis of published raw data using the Wilcoxon signed rank test

Kannenberg A, et al.: Benefits of MPKs in limited community ambulators: A systematic review of the literature. JRRD 2015; 51(10): 1469-1496.


non-MPK C-leg

Courtesy of Michael Leach, CPO,Ottobock


Which clinical benefits can be supported by evidence?

improved safety – less stumbles and falls (up to 80%!), improved balance and confidence (Kannenberg et al. 2014, Highsmith 2014, Burnfield et al. 2012, Highsmith et al. 2010,

Blumentritt et al. 2009, Hafner et al. 2009 and 2007, Kahle et al. 2008, Kaufman et al. 2007)

18

C-Leg/Compact vs. non-MPK´s

improved and faster slope negotiation (Kannenberg et al. 2014, Highsmith et al. 2013, Burnfield

et al. 2012, Hafner et al. 2009 and 2007)

improved and faster negotiation of uneven terrain and obstacles (Kannenberg et

al. 2014, Hafner et al. 2009 and 2007, Kahle et al. 2008, Seymour et al. 2007)

improved stair descent (Kannenberg et al. 2014, Hafner et al. 2009 and 2007, Kahle et al. 2008,

Schmalz et al. 2007 and 2002)

reduced cognitive demand to walk and improved multi-tasking (Morgan et al. 2015,

Kannenberg et al. 2014, Hafner et al. 2009, Williams et al. 2006)

potential to increase overall mobility / K-level (Kannenberg et al. 2014, Hafner et al. 2009,

Kahle et al. 2008)



19

C-Leg/Compact vs. non-MPK´s in K2 patients

Up to 80% reduction in falls, reduced risk of falling, improved balance confidence

14-25% faster walking speed on level ground

20% faster walking speed on uneven terrain

30% faster slope descent, improved quality of stair descent

improved performance in activities of community ambulation – about 50% of K2 improved mobility level to K3

improved indoor ADL performance

(Kannenberg et al. 2014, Eberly et al. 2013, Burnfield et al. 2012, Theeven et al. 2012 and 2011, Hafner et al. 2009, Kahle et al. 2008)


Courtesy of Dale Berry, CPO, Hanger Clinic

Improved slope ambulation and reduced cognitive load


Improved stair ambulation and multi-tasking

Courtesy of Dale Berry, CPO, Hanger Clinic


The Genium Bionic Prosthetic Knee:A Further Advancement of MPKs

Andreas Kannenberg, MD PhD, Executive Medical Director North America


Clinical study Genium v. C-Leg v. able-bodied subjects

Objectiveto compare Genium and C-Leg in K3 unilateral TF amputees in terms of: function safety quality of life

Study population

20 amputees (16 males, 4 females, age 46.5 ± 14.2 yrs)

• unilateral MFCL-3 TF or knee disarticulation• experience with the C-Leg for at least 1 year

5 able-bodied subjects as physiologic controls


Enrolled patients Randomization

C-Leg

C-LegGenium

Genium

C-Leg

C-Leg

C-Leg

60 days

2 weeks

acclimation: 67.9+27.1 days

acclimation: 67.9+27.1 days

2 weeks

Study design Genium v. C-leg


Highsmith MJ, Kahle JT, Miro RM, Lura DJ, Dubey RV, Carey SL, Quillen WS, Megelkoch LJ: Perceived differencesbetween the Genium and the C-Leg microprocessor prosthetic knees in prosthetic-related function and quality oflife. Techn Innov 2014, 15: 369-375

Outcome measures

Genium v. C-Leg

Prosthesis Evaluation Questionnaire (PEQ) and its subdomains Ambulation Utility Well-Being Perceived response Sounds Residual limb health Social burden Frustration Appearance

measure perceived prosthetic function and prosthesis-related quality of life using an ordinal scaling (0-7).



Results: PEQ (*p≤ .05)

Genium

C-Leg


Results: PEQ

Histograms

0

10

20

30

40

50

60

0 1 2 3 4 5 6 7

Residual limb health

C-Leg

Genium

0

10

20

30

40

50

60

70

0 1 2 3 4 5 6 7

Utility

0

5

10

15

20

25

30

35

40

0 1 2 3 4 5 6 7

Social burden



Results: Individual PEQ items and aggregate score

Aggregate PEQ score (items of all subdomains) is significantly higherwhen using Genium (p<.001).


10 ADLs• Carry a weighted pot a distance of 1 m• Donning and removing a jacket • Place and remove a sponge from an

adjustable shelf• Floor sweeping with broom and dustpan• Pick up four scarves from the floor• Sit and stand up from the floor• Carry groceries• Stair climbing• Moving laundry from washer to dryer• 6 minute walk test

PFP-10 Subdomains

• Upper body strength

• Upper body flexibility

• Lower body strength

• Balance and Coordination

• Endurance

SOFTWARE

Physical Functional Performance Measure (PFP-10)

Highsmith MJ: Comparative outcomes of the C-leg and X2 prosthetic knees prosthesis. Dissertation, University of South Florida, Tampa, December 2012, publications in preparation


+ Genium vs C-Leg (p<0.05)

++ C-Leg vscontrol (p<0.05)

C-Leg

Genium

Controls

Results: PFP-10 subdomains

Highsmith MJ, Kahle JT, Miro RM, Cress ME, Lura DJ, Dubey RV, Carey SL, Quillen WS, Megelkoch LJ: Effects of the Genium Knee in Persons with Transfemoral Amputation using the Continuous Scale Physical Functional Performance-10 (CS-PFP10) Assessment. Accepted by J Rehabil Res Dev, in press.


Results: PFP-10 subdomain summary

Highsmith MJ, Kahle JT, Miro RM, Cress ME, Lura DJ, Dubey RV, Carey SL, Quillen WS, Megelkoch LJ: Effects of the Genium Knee in Persons with Transfemoral Amputation using the Continuous Scale Physical Functional Performance-10 (CS-PFP10) Assessment. Accepted by J Rehabil Res Dev, in press.

Able-bodied subjects v. amputees with Genium

significantly higher score only in the endurance domain (p=.05)

no differences in the CS-PFP total score and the other 4 domains

Able-bodied subjects v. amputees with C-Leg

Significantly higher scores in the CS-PFP total score and 4/5 domains,

except upper body strength

Genium v. C-Leg

Significantly higher CS-PFP total score (p=.03)

Significantly higher scores in 3/5 domains (upper body flexibility, balance,

endurance), except upper body strength and lower body strength


Study design

14 wounded servicemembers with a unilateral transfemoral amputationwere studied for

- the self-sected strategy to ascend stairs (Stair Assessment Index [SAI])

- gait biomechanics during walking upstairs

when using the Ottobock X2® MP controlled prosthetic knee (meanacclimation 130 ± 41 days) as compared to the C-Leg (12 pts.) or theTotal Knee (2 pts.).

I © Otto Bock HealthCareAldridge Whitehead JM, Wolf EJ, Scoville CR, Wilken JM: Does a microprocessor-controlled prosthetic knee affect stair ascent strategies in persons with transfemoral amputations? Clin Orthop Rel Res 2014 Feb 11 [epub ahead of print].


Stair Assessment Index (SAI)

I © Otto Bock HealthCare

Score Mobility Descriptor

0 Cannot do/ refuses to do

1 Needs assist

2 With rail and assistive device, step-to pattern

3 With rail, step-to pattern

4 With assistive device, step-to pattern

5 Without rail or assistive device, step-to pattern

6 With rail and assistive device, skipping step pattern

7 With rail, skipping step pattern

8 With assistive device, skipping step pattern

9 Without rail or assistive device, skipping step pattern

10 With rail and assistive device, step-over-step pattern

11 With rail, step-over-step pattern

12 With assistive device, step-over-step pattern

13 Without rail or assistive device, step-over-step pattern

Hafner BJ, Willingham LL, Buell NC, Allyn KJ, Smith DG: Evaluation of Function, Performance, and Preference as Transfemoral Amputees Transition from Mechanical to Microprocessor Control of the Prosthetic Knee. Arch Phys Med Rehabil 2007; 88: 207-217


Results

Self-selected stair ascend strategy


step-over-

step (A)

step-to

(B)

skip-step

(C)

X2 10 2 2

C-Leg /

NMPK

1 10 3


Results

Stair Assessment Index (SAI) - medians

X2 11 (step-over-step with handrail use)

C-Leg 5 (step-to without handrail use)

Significantly improved quality of stair ascend (p=.005).




improved and more consistent, speed-independent toe clearance due to improved

swing knee flexion control (Bellmann et al. 2012, Lura et al. 2015)

36

Genium/X3 vs. “standard“ MPK´s (e. g. C-Leg)

improved swing release and toe clearance in small steps (Bellmann et al. 2012)

safe walking backwards (Kannenberg et al. 2013)

improved knee flexion and thus toe clearance in slope ascent and descent (Bellmann et

al. 212, Lura et al. 2015), greater perceived ease of slope negotiation (Kannenberg et al. 2013)

tendency to greater ease of uneven terrain negotiation (Highsmith et al. 2014, Kannenberg et al.

2013)

70-80% of subjects adopt reciprocal stair ascent (Aldridge Whitehead et al. 2014, Highsmith et al.

2014, Schmalz et al. 2014, Bellmann et al. 2012), greater ease of stair ascent and descent

(Kannenberg et al. 2013)

Greater perceived safety and ease of ADL execution (Kannenberg et al. 2013) and improved

prosthetic function (Highsmith et al. 2014)

improved ability to stand still for longer periods of time (Bellmann et al. 2012)


Genium/X3: Stair climbing


Genium/X3: Stepping over obstacles

Stepping over obstacles with the prosthesis (left leg)

Thank you

[email protected]

for your attention.

Documents

Evidence for the Benefits of Microprocessor Controlled Prosthetic … · 2020-04-28 · Bellmann M, Schmalz T, Blumentritt S: Comparative biomechanical analysis of current microprocessor