Combining Prosthetic Technologies

By considering the impact of different prosthetic technology on suspension, temperature, humidity and interface loads, engineers can help protect the residual limb against further health problems. Combining these technologies can further augment the benefits of each. There is a theory that the use of EV with a perforated liner, such as Silcare Breathe, may further enhance the effectiveness for wound healing because the vacuum is acting directly on the residual limb skin73.

There is a theory that the use of EV with a perforated liner, such as Silcare Breathe, may further enhance the effectiveness for wound healing because the vacuum is acting directly on the residual limb skin73.

Silcare Breathe Cushion Liner

Optimal control of a prosthetic limb depends on a comfortable and secure connection between limb and socket. Modern liner technology provides excellent cushioning, but the impermeable and insulating materials can allow a build-up of heat and moisture so they begin to slip and chafe. Air, perspiration and unnecessary movement can cause a loss of connection, compromised stability and damage to residual skin, potentially affecting mobility, safety and independence.

The patented technology of Silcare Breathe works by letting the air and perspiration that are often trapped between the liner and skin to escape through specially designed laser drilled perforations.  The air and moisture are then expelled from the socket as the wearer walks, resulting in drier skin and a healthier environment for the residual limb.  This helps to increase comfort and control, and reduce the damaging effects of relative motion on damp tissues that is often encountered with standard prosthetic liners.

Silcare Breathe Locking Liner

The Silcare Breathe Locking Liner combines the patented technology of the Silcare Breathe Cushion Liner, with the security of a locking system and unique one way valve on the liner, creating an airtight seal between the skin and the inner surface of the liner.

No separate suspension sleeve is required with Silcare Breathe Locking Liner, contributing to a cooler environment for skin and a more comfortable limb and socket connection.

Uni-directional stretch at the distal end resists pistoning whilst bi-directional stretch at the proximal end allows for comfortable knee flexion, whilst the TendressTM Finish means a lower coefficient of friction than standard silicone reduces shear stress on the skin.

EchelonVAC combines EV suspension with hydraulic ankle technology. It exploits the movement of the hydraulic piston in the ankle mechanism to draw extra air out of the socket mechanically and increase the level of vacuum inside the socket. This combines and enhances the benefits of EV with those of hydraulic ankles, including increased ground clearance74, greater symmetry45,75 and faster walking speeds45,76.


Optimal socket connection is critical to an amputee’s comfort, security and stability. By pairing Biomimetic Hydraulic Technology with an elevated vacuum system, the design of EchelonVAC works to create a secure and comfortable socket connection.

By harnessing natural ankle motion, EchelonVAC quietly creates elevated vacuum, helping to maintain an optimally fitting socket throughout the day.


  1. Tang J, McGrath M, Laszczak P, Jiang L, Bader DL, Moser D, Zahedi S. Characterisation of dynamic couplings at lower limb residuum/socket interface using 3D motion capture. Med Eng Phys 2015; 37: 1162–1168.
  2. Tang J, McGrath M, Hale N, Jiang L, Bader D, Laszczak P, Moser D, Zahedi S. A combined kinematic and kinetic analysis at the residuum/socket interface of a kneedisarticulation amputee. Med Eng Phys 2017; 49: 131–139.
  3. Salami F, Heitzmann DW, Leboucher J, Alimusaj M, Wolf SI. P 122-Modelling of residual limb and socket interaction in individuals with trans-femoral prosthesis during walking. Gait Posture. 2018;65:440-1. 
  4. Fletcher DD, Andrews KL, Butters MA, Jacobsen SJ, Rowland CM, Hallett JW. Rehabilitation of the geriatric vascular amputee patient: a population-based study. Arch Phys Med Rehabil 2001; 82: 776–779. 
  5. Centers for Disease Control and Prevention. National diabetes statistics report, 2017. Atlanta GA Cent Dis Control Prev US Dep Health Hum Serv. 
  6. American Diabetes Association. Economic costs of diabetes in the US in 2017. Diabetes Care 2018; 41: 917–928.
  7. American Diabetes Association. Economic costs of diabetes in the US in 2012. Diabetes Care 2013; 36: 1033–1046. 
  8. Cost of Diabetes, (accessed 1 August 2019). 
  9. Diabetes UK. New diabetes prevalence figures for England, uk/about_us/news/new-diabetes-prevalence-figures-for-england (2016, accessed 1 August 2019).
  10. Greenhalgh DG. Wound healing and diabetes mellitus. Clin Plast Surg 2003; 30: 37–45. 
  11. Caputo GM, Cavanagh PR, Ulbrecht JS, Gibbons GW, Karchmer AW. Assessment and Management of Foot Disease in Patients with Diabetes. N Engl J Med 1994; 331: 854–860. 
  12. Posnett J, Franks P. The burden of chronic wounds in the UK. Diabet Med 2008; 14: S7–S85. 
  13. Nakajima H, Yamamoto S, Katsuhira J. Effects of diabetic peripheral neuropathy on gait in vascular trans-tibial amputees. Clin Biomech Bristol Avon 2018; 56: 84–89. 
  14. Johannesson A, Larsson G-U, Ramstrand N, Turkiewicz A, Wiréhn A-B, Atroshi I. Incidence of lower-limb amputation in the diabetic and nondiabetic general population: a 10-year population-based cohort study of initial unilateral and contralateral amputations and reamputations. Diabetes Care 2009; 32: 275–280. 
  15. Izumi Y, Satterfield K, Lee S, Harkless LB. Risk of reamputation in diabetic patients stratified by limb and level of amputation a 10-year observation. Diabetes Care 2006; 29: 566–570. 
  16. Dillingham TR, Pezzin LE, Shore AD. Reamputation, mortality, and health care costs among persons with dysvascular lower-limb amputations. Arch Phys Med Rehabil 2005; 86: 480–486. 
  17. Kulkarni J, Wright S, Toole C, Morris J, Hirons R. Falls in patients with lower limb amputations: prevalence and contributing factors. Physiotherapy 1996; 82: 130–136.
  18. Gerschutz MJ, Hayne ML, Colvin JM, Denune JA. Dynamic Effectiveness Evaluation of Elevated Vacuum Suspension. JPO J Prosthet Orthot 2015; 27: 161–165. 
  19. Board WJ, Street GM, Caspers C. A comparison of trans-tibial amputee suction and vacuum socket conditions. Prosthet Orthot Int 2001; 25: 202–209. 
  20. Klute GK, Berge JS, Biggs W, Pongnumkul S, Popovic Z, Curless B. Vacuum-assisted socket suspension compared with pin suspension for lower extremity amputees: effect on fit, activity, and limb volume. Arch Phys Med Rehabil 2011; 92: 1570–1575. 
  21. Gholizadeh H, Lemaire ED, Eshraghi A. The evidence-base for elevated vacuum in lower limb prosthetics: Literature review and professional feedback. Clin Biomech 2016; 37: 108–116. 
  22. Darter BJ, Sinitski K, Wilken JM. Axial bone-socket displacement for persons with a traumatic transtibial amputation: The effect of elevated vacuum suspension at progressive body-weight loads. Prosthet Orthot Int 2016; 40: 552–557. 
  23. Scott H, Hughes J. Investigating The Use Of Elevated Vacuum Suspension On The Adult PFFD Patient: A Case Study. ACPOC 2013; 19: 7–12.
  24. Ferraro C. Outcomes study of transtibial amputees using elevated vacuum suspension in comparison with pin suspension. JPO J Prosthet Orthot 2011; 23: 78–81. 
  25. Rosenblatt NJ, Ehrhardt T. The effect of vacuum assisted socket suspension on prospective, community-based falls by users of lower limb prostheses. Gait Posture 2017; 55: 100–103.
  26. Samitier CB, Guirao L, Costea M, Camós JM, Pleguezuelos E. The benefits of using a vacuum-assisted socket system to improve balance and gait in elderly transtibial amputees. Prosthet Orthot Int 2016; 40: 83–88. 
  27. Tinetti ME, Speechley M, Ginter SF. Risk factors for falls among elderly persons living in the community. N Engl J Med 1988; 319: 1701–1707.
  28. Quai TM, Brauer SG, Nitz JC. Somatosensation, circulation and stance balance in elderly dysvascular transtibial amputees. Clin Rehabil 2005; 19: 668–676. 
  29. Xu H, Greenland K, Bloswick D, Zhao J, Merryweather A. Vacuum level effects on gait characteristics for unilateral transtibial amputees with elevated vacuum suspension. Clin Biomech Bristol Avon 2017; 43: 95–101. 
  30. Ferreira AEK, Neves EB. A comparison of vacuum and KBM prosthetic fitting for unilateral transtibial amputees using the Gait Profile Score. Gait Posture 2015; 41: 683–687. 
  31. Sanders JE, Youngblood RT, Hafner BJ, Ciol MA, Allyn KJ, Gardner D, Cagle JC, Redd CB, Dietrich CR. Residual limb fluid volume change and volume accommodation: Relationships to activity and self-report outcomes in people with trans-tibial amputation. Prosthet Orthot Int 2018; 0309364617752983. 
  32. Youngblood RT, Hafner BJ, Allyn KJ, Cagle JC, Hinrichs P, Redd C, Vamos AC, Ciol MA, Bean N, Sanders JE. Effects of activity intensity, time, and intermittent doffing on daily limb fluid volume change in people with transtibial amputation. Prosthet Orthot Int 2018; 309364618785729. 
  33. Zachariah SG, Saxena R, Fergason JR, Sanders JE. Shape and volume change in the transtibial residuum over the short term: preliminary investigation of six subjects. J Rehabil Res Dev 2004; 41: 683–694. 
  34. Sanders JE, Harrison DS, Myers TR, Allyn KJ. Effects of elevated vacuum on in-socket residual limb fluid volume: Case study results using bioimpedance analysis. J Rehabil Res Dev 2011; 48: 1231. 
  35. Street G. Vacuum suspension and its effects on the limb. Orthopadie Tech 2006; 4: 1–7. 
  36. Goswami J, Lynn R, Street G, Harlander M. Walking in a vacuum-assisted socket shifts the stump fluid balance. Prosthet Orthot Int 2003; 27: 107–113. 
  37. McGrath M, Laszczak P, McCarthy J, Moser D, Zahedi S. The biomechanical effects on gait of elevated vacuum suspension compared to suction suspension. Paper presented at ISPO World Congress; Cape Town, South Africa; 2017.
  38. Dudek NL, Marks MB, Marshall SC, Chardon JP. Dermatologic conditions associated with use of a lower-extremity prosthesis. Arch Phys Med Rehabil 2005; 86: 659–663. 
  39. Dudek NL, Marks MB, Marshall SC. Skin problems in an amputee clinic. Am J Phys Med Rehabil 2006; 85: 424–429.
  40. Beil TL, Street GM. Comparison of interface pressures with pin and suction suspension systems. J Rehabil Res Dev 2004; 41: 821.
  41. Beil TL, Street GM, Covey SJ. Interface pressures during ambulation using suction and vacuum-assisted prosthetic sockets. J Rehabil Res Dev 2002; 39: 693.
  42. Rosenblatt NJ, Ehrhardt T, Fergus R, Bauer A, Caldwell R. Effects of Vacuum-Assisted Socket Suspension on Energetic Costs of Walking, Functional Mobility, and Prosthesis- Related Quality of Life. JPO J Prosthet Orthot 2017; 29: 65–72.
  43. Portnoy S, Kristal A, Gefen A, Siev-Ner I. Outdoor dynamic subject-specific evaluation of internal stresses in the residual limb: hydraulic energy-stored prosthetic foot compared to conventional energy-stored prosthetic feet. Gait Posture 2012; 35: 121–125.
  44. Xu H, Greenland K, Bloswick D, Zhao J, Merryweather A. Vacuum level effects on knee contact force for unilateral transtibial amputees with elevated vacuum suspension. J Biomech 2017; 57: 110–116. 
  45. De Asha AR, Munjal R, Kulkarni J, Buckley JG. Walking speed related joint kinetic alterations in trans-tibial amputees: impact of hydraulic’ankle’damping. J Neuroengineering Rehabil 2013; 10: 1.
  46. McGrath M, Laszczak P, Zahedi S, Moser D. The influence of a microprocessorcontrolled hydraulic ankle on the kinetic symmetry of trans-tibial amputees during ramp walking: a case series. J Rehabil Assist Technol Eng 2018; 5: 2055668318790650. 
  47. McGrath M, Laszczak P, Zahedi S, Moser D. Microprocessor knees with “standing support” and articulating, hydraulic ankles improve balance control and interlimb loading during quiet standing. J Rehabil Assist Technol Eng 2018; 5: 2055668318795396.
  48. Moore R. Effect of a Prosthetic Foot with a Hydraulic Ankle Unit on the Contralateral Foot Peak Plantar Pressures in Individuals with Unilateral Amputation. JPO J Prosthet Orthot; 30, Prosthetic_Foot_with_a_Hydraulic_Ankle.11.aspx (2018).
  49. Wurdeman SR, Stevens PM, Campbell JH. Mobility Analysis of AmpuTees (MAAT I): Quality of life and satisfaction are strongly related to mobility for patients with a lower limb prosthesis. Prosthet Orthot Int 2017; 0309364617736089. 
  50. Huang C, Leavitt T, Bayer LR, Orgill DP. Effect of negative pressure wound therapy on wound healing. Curr Probl Surg 2014; 51: 301–331. 
  51. Philbeck JT, Whittington KT, Millsap MH, Briones RB, Wight DG, Schroeder WJ. The clinical and cost effectiveness of externally applied negative pressure wound therapy in the treatment of wounds in home healthcare Medicare patients. Ostomy Wound Manage 1999; 45: 41–50. 
  52. Armstrong DG, Lavery LA, Diabetic Foot Study Consortium. Negative pressure wound therapy after partial diabetic foot amputation: a multicentre, randomised controlled trial. Lancet Lond Engl 2005; 366: 1704–1710. 
  53. Hoskins RD, Sutton EE, Kinor D, Schaeffer JM, Fatone S. Using vacuum-assisted suspension to manage residual limb wounds in persons with transtibial amputation: a case series. Prosthet Orthot Int 2014; 38: 68–74. 
  54. Traballesi M, Delussu AS, 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 2012; 48: 613–23. 
  55. Brunelli S, Averna T, Delusso M, Traballesi M. Vacuum assisted socket system in transtibial amputees: Clinical report. Orthopädie-Technik Quarterly. Engl Ed; 2. 
  56. Arndt B, Caldwell R, Fatone S. Use of a partial foot prosthesis with vacuum-assisted suspension: A case study. JPO J Prosthet Orthot 2011; 23: 82–88. 
  57. Carvalho JA, Mongon MD, Belangero WD, Livani B. A case series featuring extremely short below-knee stumps. Prosthet Orthot Int 2012; 36: 236–238.
  58. Sutton E, Hoskins R, Fosnight T. Using elevated vacuum to improve functional outcomes: A case report. JPO J Prosthet Orthot 2011; 23: 184–189.
  59. Rink C, Wernke MM, Powell HM, Gynawali S, Schroeder RM, Kim JY, Denune JA, Gordillo GM, Colvin JM, Sen CK. Elevated vacuum suspension preserves residual-limb skin health in people with lower-limb amputation: Randomized clinical trial. J Rehabil Res Dev 2016; 53: 1121–1132.
  60. Hagberg K, Brånemark R. Consequences of non-vascular trans-femoral amputation: a survey of quality of life, prosthetic use and problems. Prosthet Orthot Int 2001; 25: 186–194.
  61. Meulenbelt HE, Geertzen JH, Jonkman MF, Dijkstra PU. Determinants of skin problems of the stump in lower-limb amputees. Arch Phys Med Rehabil 2009; 90: 74–81.
  62. Berke GM, L-CPO JH, Nguyen V. Comparison of satisfaction with current prosthetic care in veterans and servicemembers from Vietnam and OIF/OEF conflicts with major traumatic limb loss. J Rehabil Res Dev 2010; 47: 361.
  63. Hansen C, Godfrey B, Wixom J, McFadden M. Incidence, severity, and impact of hyperhidrosis in people with lowerlimb amputation. J Rehabil Res Dev 2015; 52: 31.
  64. Strutton DR, Kowalski JW, Glaser DA, Stang PE, others. US prevalence of hyperhidrosis and impact on individuals with axillary hyperhidrosis: results from a national survey. J Am Acad Dermatol 2004; 51: 241–248.
  65. Gonzalez EG, Corcoran PJ, Reyes RL. Energy expenditure in below-knee amputees: correlation with stump length. Arch Phys Med Rehabil 1974;55(3):111.
  66. Seymour R. Prosthetics and Orthotics: Lower Limb and Spinal. Lippincott Williams & Wilkins, 2002.
  67. Hachisuka K, Matsushima Y, Ohmine S, Shitama H, Shinkoda K. Moisture permeability of the total surface bearing prosthetic socket with a silicone liner: is it superior to the patella-tendon bearing prosthetic socket? J Univ Occup Environ Health 2001; 23: 225–232.
  68. Klute GK, Rowe GI, Mamishev AV, Ledoux WR. The thermal conductivity of prosthetic sockets and liners. Prosthet Orthot Int 2007; 31: 292–299.
  69. Webber CM, Klittich MR, Dhinojwala A, Davis BL. Thermal conductivities of commercially available prosthetic materials. JPO J Prosthet Orthot 2014; 26: 212–215.
  70. Meulenbelt HE, Geertzen JH, Dijkstra PU, Jonkman MF. Skin problems in lower limb amputees: an overview by case reports. J Eur Acad Dermatol Venereol 2007; 21: 147–155.
  71. Almassi F, Emadi N, Mousavi B, Masumi M, Souroush MR. Dermatosis contributing factors in bilateral lower limb war-amputees. Pak J Biol Sci PJBS 2010; 13: 78–82.
  72. Ghoseiri K, Safari MR. Prevalence of heat and perspiration discomfort inside prostheses: Literature review. J Rehabil Res Dev 2014; 51: 855.
  73. McGrath M, McCarthy J, Gallego A, Kercher A, Zahedi S, Moser D. The influence of perforated prosthetic liners on residual limb wound healing: a case report. Can Prosthet Orthot J 2019; 2: No.3. 
  74. Johnson L, De Asha AR, Munjal R, Kulkarni J, Buckley JG. Toe clearance when walking in people with unilateral transtibial amputation: effects of passive hydraulic ankle. J Rehabil Res Dev 2014; 51: 429. 
  75. Moore R. Effect on Stance Phase Timing Asymmetry in Individuals with Amputation Using Hydraulic Ankle Units. JPO J Prosthet Orthot 2016; 28: 44–48.
  76. Barnett CT, Brown OH, Bisele M, Brown MJ, De Asha AR, Strutzenberger G. Individuals with Unilateral Transtibial Amputation and Lower Activity Levels Walk More Quickly when Using a Hydraulically Articulating Versus Rigidly Attached Prosthetic Ankle-Foot Device. JPO J Prosthet Orthot 2018; 30: 158–64.