Clinical Outcomes

Summary Statement

Vacuum suspension was first introduced to the prosthetic field in 1995¹ and became commercially available in 1999². Since then, numerous published research documents have demonstrated the clinical value of this prosthetic suspension system. The results report quantified improvements associated with wearing an elevated vacuum suspended socket such as reduced pistoning or vertical movement of the socket related to the residual limb^2-5, reduced residual limb volume fluctuations^2,6,7, reduction of positive pressures on the residual limb tissues from the prosthetic socket^3,8, improvements in gait and balance^2,3,9-11, and documentation of wound healing while continuing to wear a prosthesis^11-14.  Qualitative results indicate higher satisfaction and quality of life of amputee prosthesis users utilizing EVS^3,6,9-11,13.  To investigate the documented reports of wound healing with elevated vacuum suspension, WillowWood partnered with The Ohio State University and developed a method to quantify skin health and blood circulation¹⁵.  The study found a promotion of skin barrier function, increase blood perfusion during walking, and a reduction in reactive hyperemia following socket doffing when using elevated vacuum suspension compared to non-vacuum suspension¹⁶.  Taken together, the results suggest that EVS-dependent differences in the prosthetic socket residual limb interface account for residual limb health improvement in part by beneficial changes in residual limb perfusion and stress applied to the soft tissues of the residual limb.

Research by WillowWood

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Peer Reviewed: 
Standardized Approach to Quantitatively Measure Residual Limb Skin Health in Individuals with Lower Limb Amputation, Advances in Wound Care, Volume 6, Number 7
Elevated Vacuum Suspension Preserves Residual-limb Skin Health in People with Lower-limb Amputation: Randomized Clinical Trial, Journal of Rehabilitation Research and Development, Volume 53, Number 6

Other References:
Quantification of Residual Limb Skin Health and Circulation in Response to Elevated Vacuum Suspension, AAOP 41st Annual meeting and Scientific Symposium, February 19, 2015

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1. Caspers CA. Hypobarically-controlled artificial limb for amputees. US patent number 5,549,709.

2. Board W, Street G, Caspers C. A comparison of transtibial amputee suction and vacuum socket conditions. Prosthetics and Orthotics International. 25, 202-209. (2001).

3. Kahle J, Highsmith J. Transfemoral sockets with vacuum-assisted suspension comparison of hip kinematics, socket position, contact pressure, and preference: Ischial containment versus brimless. Journal of Rehabilitation Research and Development. 50, 1241-1252. (2013).

4. Wernke M, Schroeder R, Haynes M, Nolt L, Albury A, Colvin J. Progress Toward Optimizing Prosthetic Socket Fit and Suspension Using Elevated Vacuum to Promote Residual Limb Health. Adv Wound Care. 2017. 6 (7): p 233-239.

5. Gerschutz M, Haynes M, Colvin J, Denune J. Dynamic Effectiveness Evaluation of Elevated Vacuum Suspension.  Journal of Prosthetics and Orthotics. 27 (4) 161-165. (2015)

6. Goswami J, Lynn R, Street G, Harlander M. Walking in a vacuum-assisted socket shifts the stump fluid balance. Prosthetics and Orthotics International. 23. 107-113. (2003).

7. Sanders J, Harrison D, Myers T, Allyn K. Effects of elevated vacuum on in-socket residual limb fluid volume: Case study results using bioimpedance analysis. Journal of Rehabilitation Research and Development. 48. 1231-1248. (2011).

8. Beil T, Street G, Covey S. Interface pressures during ambulation using suction and vacuum-assisted prosthetic sockets. Journal of rehabilitation Research and Development. 39. 693-700. (2002).

Summary Statement

The team at WillowWood was the first to quantify the effects of elevated vacuum suspension on skin tissue health.  The study found a promotion of skin barrier function, increase blood perfusion during walking, and a reduction in reactive hyperemia following socket doffing when using elevated vacuum suspension compared to non-vacuum suspension¹.  Taken together, the results suggest that EVS-dependent differences in the prosthetic socket residual limb interface account for residual limb health improvement in part by beneficial changes in residual limb perfusion and stress applied to the soft tissues of the residual limb.  This hypothesis is supported by the literature that shows reduced pistoning or vertical movement of the socket related to the residual limb^2-5, reduced residual limb volume fluctuations^2,6,7, reduction of positive pressures on the residual limb tissues from the prosthetic socket^3,8, improvements in gait and balance^2,3,9-11 that could lead to the reports of wound healing^11-14.

Previously, the team showed that the quality of socket fit matters, where both tight and loose sockets will result in greater movement of the limb inside the socket compared to a well-fit socket on a bench top model¹⁵.  Taken this into account and building upon a previous clinical trial¹⁶, the team conducted a study to measure limb motion inside of a 3 different sockets using an inductive sensor; a well fit, a slightly loose, and a slightly tight.  The study was presented at national trade shows.  It confirmed the findings of the bench top study, where a well-fit socket resulted in the least amount of motion.  Interesting, a tight fitting socket resulting in the most motion for the prosthesis users.  The use of elevated vacuum suspension significantly reduced movement, particularly non-vertical movement of the limb.  This could explain the reports of better proprioception with elevated vacuum suspended prostheses.  Further extrapolating the results of the study to project the limb movement that would occur if a prosthesis user walked the daily recommended 10,000 steps, they would experience over 55 meters of motion inside their socket with a passive suction socket.  With elevated vacuum suspension, this movement could be reduced to as little as 5 meters over the same amount of steps.  This would certainly reduce stress on the limb and prevent wounds from developing.

Research by WillowWood

Download Summary PDF

Peer Reviewed: 
Dynamic Effectiveness Evaluation of Elevated Vacuum Suspension, Journal of Prosthetics and Orthotics, Volume 27, Number 4, 2015
Progress Toward Optimizing Prosthetic Socket Fit and Suspension Using Elevated Vacuum to Promote Residual Limb Health, Advances in Wound Care, Volume 00, Number 00

Click here for full bibliography

1. Rink C, Wernke M, Powell H, Gynawali S, Schroeder R, Kim J, Denune J, Gordillo G, Colvin J, Sen C. Elevated Vacuum Suspension Preserves Residual Limb Skin Health in Lower Limb Amputees: Randomized Clinical Trial.  2016; 53 (6): 1121-1132.

2. Board W, Street G, Caspers C. A comparison of transtibial amputee suction and vacuum socket conditions. Prosthetics and Orthotics International. 25, 202-209. (2001).

3. Kahle J, Highsmith J. Transfemoral sockets with vacuum-assisted suspension comparison of hip kinematics, socket position, contact pressure, and preference: Ischial containment versus brimless. Journal of Rehabilitation Research and Development. 50, 1241-1252. (2013).

4. Wernke M, Schroeder R, Haynes M, Nolt L, Albury A, Colvin J. Progress Toward Optimizing Prosthetic Socket Fit and Suspension Using Elevated Vacuum to Promote Residual Limb Health. Adv Wound Care. 2017. 6 (7): p 233-239.

5. Gerschutz M, Haynes M, Colvin J, Denune J. Dynamic Effectiveness Evaluation of Elevated Vacuum Suspension.  Journal of Prosthetics and Orthotics. 27 (4) 161-165. (2015)

6. Goswami J, Lynn R, Street G, Harlander M. Walking in a vacuum-assisted socket shifts the stump fluid balance. Prosthetics and Orthotics International. 23. 107-113. (2003).

7. Sanders J, Harrison D, Myers T, Allyn K. Effects of elevated vacuum on in-socket residual limb fluid volume: Case study results using bioimpedance analysis. Journal of Rehabilitation Research and Development. 48. 1231-1248. (2011).

8. Beil T, Street G, Covey S. Interface pressures during ambulation using suction and vacuum-assisted prosthetic sockets. Journal of rehabilitation Research and Development. 39. 693-700. (2002).

9. Kahle J, Highsmith J. Transfemoral interfaces with vacuum assisted suspension comparison of gait, balance, and subjective analysis: Ischial containment versus brimless. Gait and Posture. 40, 315-320. (2014).

10. Samitier C, Guirao L, Costea M, Camos J, Pleguezuelos E. The benefits of using a vacuum-assisted socket system to improve balance and gait in elderly transtibial amputees. Prosthetics and Orthotics International. (2014).

11. Ferraro C. Outcomes Study of Transtibial Amputees Using Elevated Vacuum Suspension in Comparison with Pin Suspension. Journal of Prosthetics and Orthotics. 23 (2) p 78-81. (2011)

12. Traballesi M, Delussu A. Fusco A, Iosa M, Averna T, Pellegrini R, Brunelli S. Residual limb wounds or ulcers heal in transtibial amputees using an active suction socket system. A randomized controlled study. Eur. J. Phys. Rehabil. Med. 48. 613-623. (2012).

13. Hoskins R. Sutton E. Kinor D. Schaeffer J, Fatone S. Using vacuum-assisted suspension to manage residual limb wounds in persons with transtibial amputation: A case series. Prosthetics and Orthotics International. (2012)

14. Brunelli S, Averna T, Delusso S, Trabellesi M. Vacuum assisted socket system in transtibial amputees: Clinical report. Orthopaedic Technik Quarterly. (2009).

15. Wernke M, Schroeder R, Haynes M, Nolt L, Albury A, Colvin J. Progress toward optimizing prosthetic socket fit and suspension using elevated vacuum suspension to promote residual limb health.  Advances in Wound Care. 2017. DOI: 10.1089/wound.2016.0719.

16. Gerschutz M, Haynes M, Colvin J, Denue J. Dynamic Effectiveness Evaluation of Elevated Vacuum Suspension.  2015; 27 (4): p 161 – 165.