Ottobock Kenevo Microprocessor Knee: Evidence Essentials for K2 Patients

Safety

Patient need/deficit: Patient stumbles and/or falls repeatedly

• Significant reduction in falls of up to 80% (Wurdeman et al., 2025; Hahn et al., 2021; Davie-Smith et al., 2021; Kaufman et al., 2018; Mileusnic et al., 2017; Wong et al., 2015; Hahn et al., 2015; Kannenberg et al., 2014; Hafner et al., 2009; Kahle et al., 2008)

Patient need/deficit: Patient avoids activities due to fear of falling

• Significant reduction in fear of falling (Wurdeman et al., 2025; Hahn et al., 2021; Jayaraman et al., 2021; Mileusnic et al., 2017; Wong et al., 2015; Hahn et al., 2015)

Patient need/deficit: Patient sustained fall-related injuries

• Significant reduction in the frequency of stumbles (Wurdeman et al., 2025; Mileusnic et al., 2017; Kannenberg et al., 2014; Hafner et al., 2009)
• Significant improvements in balance and indicators for the risk of falling, such as Timed-up-and-go-test, ABC scale, PEQ Addendum; Modified Falls Efficacy Scale, etc. (Wurdeman et al., 2025; Hahn et al., 2021; Davie-Smith et al., 2021; Jayaraman et al., 2021; Lansade et al., 2018; Hahn et al., 2016; Wong et al., 2015; Kannenberg et al., 2014; Burnfield et al., 2012; Hafner et al., 2007 and 2009)

Mobility

Patient need/deficit: Patient has difficulty negotiating slopes/hills

• Significant improvement in quality of slope descent towards more natural gait pattern (Kannenberg et al., 2014; Burnfield et al., 2012; Hafner et al., 2009)
• Significant increase in downhill walking speed of up to 36% (Kannenberg et al., 2014; Burnfield et al., 2012; Hafner et al., 2009)
• Significant improvement in patient-reported slope ambulation (Hahn et al., 2016)

Patient need/deficit: Patient has difficulty negotiating uneven terrain and obstacles

• Significant increase in walking speed on uneven terrain and obstacle courses of up to 20% (Kannenberg et al., 2014; Hafner et al., 2009; Kahle et al., 2008)
• Significant improvement in patient-reported uneven terrain and obstacle negotiation (Hahn et al., 2016)

Patient need/deficit: Patient has difficulty descending stairs with reciprocal (step-over-step) gait

• Significant improvement in quality of stair descent towards more natural gait pattern (Kannenberg et al., 2014; Hafner et al., 2009; Kahle et al., 2008;)
• Significant improvement in patient-reported stair ambulation (Hahn et al., 2016)

Patient need/deficit: Patient has difficulty with dual tasking while walking with the prosthesis

• Significantly improved capacity and performance in executing a concurrent task while walking with the prosthesis (Mileusnic et al., 2017; Hahn et al., 2016; Hahn et al., 2015; Kannenberg et al., 2014; Hafner et al., 2009)

Patient need/deficit: Patient has difficulty with performing activities of daily living

• Significantly improved performance in the execution of various activities of daily living (Wurdeman et al., 2025)
• Significantly improved performance in the execution of various activities of daily living (Kannenberg et al., 2014; Theeven et al., 2011 and 2012)
• Significant improvement in PRQ Ambulation and PEQ Utility (Hahn et al., 2021)
• Almost significant (p=0.056) but clinically meaningful improvement in patient-reported mobility (PLUS-M) (Davie-Smith et al., 2021)

Patient need/deficit: Patient is limited in his/her mobility; Patient uses a wheelchair and a prosthesis

• Significant increase in over-ground walking speed of up to 25% (Wurdeman et al., 2025; Hahn et al., 2021; Davie-Smith et al., 2021; Jayaraman et al., 2021; Eberly et al., 2014; Kannenberg et al., 2014; Kahle et al., 2008)
• Significant improvement in distance walked in the 2-minute walk test (Wurdeman et al., 2025; Davie-Smith et al., 2021)
• Significant reduction in additional use of a wheelchair from 87% to 37% of subjects (Mileusnic et al., 2017)
• Patients spent significantly more time active and significantly less time sitting (Kaufman et al., 2018)
• About 50% of K2 patients are able to improve their overall mobility level to K3 (Hahn et al., 2021; Hahn et al., 2016; Hahn et al., 2015; Kannenberg et al., 2014; Hafner et al. 2009; Kahle et al., 2008)

Quality of Life

Patient need/deficit: Patient has reduced quality of life

• Significant improvement in health-related quality of life (Davie-Smith et al., 2021)
• Preservation of quality of life of older TF amputees (avg. age 73 yrs) in a 12-month study while quality of life in the NMPK group declined significantly (Wurdeman et al., 2025)

References

• Burnfield JM, Eberly VJ, Gronely JK, Perry J, Yule WJ, Mulroy SJ. Impact of stance phase microprocessor-controlled knee prosthesis on ramp negotiation and community walking function in K2 level transfemoral amputees. Prosthet Orthot Int 2012;36(1):95-104.
• Davie-Smith F, Carse B. Comparison of patient-reported and functional outcomes following transition from mechanical to microprocessor knee in the low-activity user with a unilateral transfemoral amputation. Prosth Orthot Int 2021;45(3):198-204.
• Eberly VJ. Mulroy SJ, Gronley JK, Perry J, Burnfield JM. Impact of a stance phase microprocessor-controlled knee prosthesis on level walking in lower functioning individuals with transfemoral amputation. Prosth Orthot Int 2014;38(6):447-455.
• Hahn A, Bueschges S, Prager M, Kannenberg A. The effect of microprocessor controlled exo-prosthetic knees on limited community ambulators: systematic review and meta-analysis. Disabil Rehabil 2021 Oct 25:1-19.
• Hahn A, Lang M, Stuckart C. Analysis of clinically important factors on the performance of advanced hydraulic, microprocessor-controlled exo-prosthetic knee joints based on 899 trial fittings. Medicine. 2016;95(45):e5386.
• Hahn A, Lang M. Effects of mobility grade, age, and etiology on functional benefit and safety of subjects evaluated in more than 1200 C-Leg trial fittings in Germany. J Prosthet Orthot 2015; 27(3): 86-95.
• Hafner BJ, Smith DG. Differences in function and safety between Medicare Functional Classification Level-2 and -3 transfemoral amputees and influence of prosthetic knee joint control. J Rehabil Res Dev 2009;46(3):417-434.
• Jayaraman C, Mummidisetty CK, Albert MV, et al. Using a microprocessor knee (C-Leg) with appropriate foot transitioned individuals with dysvascular transfemoral amputations to higher performance levels: a longitudinal randomized clinical trial. J Neuroeng Rehabil. 2021;18(1):88.
• Kahle JT, Highsmith MJ, Hubbard SL. Comparison of Non-microprocessor Knee Mechanism versus C-Leg on Prosthesis Evaluation Questionnaire, Stumbles, Falls, Walking Tests, Stair Descent, and Knee Preference; J Rehabil Res Dev 2008;45(1):1-14.
• Kannenberg A, Zacharias B, Pröbsting E: Benefits of microprocessor prosthetic knees to limited community ambulators: A systematic review. J Rehabil Res Dev 2014;51(10):1469-1495.
• Kaufman KR, Bernhardt KA, Symms K. Functional assessment and satisfaction of transfemoral amputees with mobility (FASTK2): A clinical trial of microprocessor-controlled vs. non-microprocessor-controlled knees. Clin Biomech (Bristol, Avon) 2018 Oct;58:116-122.
• Mileusnic M, Hahn A, Reiter S. Effects of a novel microprocessor-controlled knee, Kenevo, on the safety, mobility, and satisfaction of lower-activity patients with transfemoral amputation. J Prosthet Orthot 2017;29(4):198-205.
• Lansade C, Vicaut E, Paysant J, Ménager D, Cristina MC, Braatz F, Domayer S, Pérennou D, Chiesa G. Mobility and safety with a microprocessor-controlled knee in moderately active amputees: A multi-centric randomized crossover trial. Ann Phys Rehabil Med 2018;61(5):278-285.
• Theeven P, Hemmen B, Rings F, Meys G, Brink P, Smeets R, Seelen H. Functional added value of microprocessor-controlled knee joints in daily life performance of Medicare Functional Classification Level-2 amputees. J Rehabil Med 2011;43(10):906-915.
• Theeven PJ, Hemmen B, Geers RP, Smeets RJ, Brink PR, Seelen HA. Influence of advanced prosthetic knee joints on perceived performance and everyday life activity of low-functional persons with a transfemoral amputation or knee disarticulation. J Rehabil Med 2012;44(5):454-461.
• Wong CK, Rheinstein J, Stern MA. Benefits for adults with transfemoral amputation and peripheral artery disease using microprocessor compared with nonmicroprocessor prosthetic knees. Am J Phys Med Rehabil 2015; 94 (10): 804-810.
• Wurdeman SR, Hafner BJ, Sawers A, England DL, Lundstrom R, Kannenber A. Assessing clinical outcomes with microprocessor knee utilization in a K2 population (ASCENT K2): randomized controlled trial results for above-knee prosthesis users over age 65. Disabil Rahabil 2025 Jul 21:1-18. doi: 10.1080/09638288.2025.2530172. Online ahead of print.