Secondary Logo

Journal Logo

Transtibial Socket Design, Interface, and Suspension

A Clinical Practice Guideline

Stevens, Phillip M., MEd, CPO, FAAOP; DePalma, Russell R., CP; Wurdeman, Shane R., PhD, MSPO, CP

JPO: Journal of Prosthetics and Orthotics: July 2019 - Volume 31 - Issue 3 - p 172–178
doi: 10.1097/JPO.0000000000000219
CME ARTICLE
Open
Take This Quiz

Materials N/A

Methods The guideline is based upon the best available evidence as it relates to socket design, interface, and suspension of definitive transtibial prostheses. Where possible, recommendations are drawn from systematic review and meta-analysis. Where this standard is unavailable, alternate academic literature has been used to support individual recommendations.

Results Recommendation 1: The static and dynamic pressure distribution of the residual limb within the socket are essential considerations in patient comfort, function and well-being.

Recommendation 2: Total surface bearing sockets are indicated to decrease fitting times and enable higher activity levels.

Recommendation 3: Compared to traditional foam-based interfaces, viscoelastic interface liners are indicated to decrease dependence on walking aides, improve suspension, improve load distribution, decrease pain and increase comfort.

Recommendation 4: Among modern suspension options, vacuum assisted suspension (VAS) sockets permits the least amount of pistoning within the socket, followed by suction suspension and then pin-lock suspension. The traditional suspension options of supracondylar, cuff and sleeve suspension provide comparatively compromised suspension.

Recommendation 5: VAS sockets are indicated to decrease daily limb volume changes of the limb in the socket while facilitating more favorable pressure distribution during gait.

Recommendation 6: VAS sockets require both awareness and compliance on the part of the end user and are not universally indicated.

Conclusions These clinical practice guidelines summarize the available evidence related to the socket design, interface, and suspension of definitive transitibial prostheses. The noted clinical practice guidelines are meant to serve on as “guides.” They may not apply to all patients and clinical situations.

PHILLIP M. STEVENS, MEd, CPO, FAAOP; and SHANE R. WURDEMAN, PhD, MSPO, CP, are affiliated with the Hanger Clinic, Salt Lake City, Utah.

RUSSELL R. DEPALMA, CP, is affiliated with Ortho Engineering Inc, Culver City, California.

Disclosures: Phillip M. Stevens, Russell R. DePalma, and Shane R. Wurdeman were employees of Hanger Clinic during the development of this work and received no external funding for the purposes of this work.

Disclosure: The authors declare no conflict of interest.

Correspondence to: Phillip M. Stevens, MEd, CPO, FAAOP, Hanger Clinic, 2785 E, 3300 S, Salt Lake City, UT 84109; email: pstevens@hanger.com

This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially without permission from the journal.

Online date: November 21, 2019

Of the 1.6 million persons living in the United States with limb loss, approximately 1.3 million (86%) have an amputation of the lower limb.1,2 Of these, estimates suggest that 28% or 378,000 individuals have transtibial amputation.3

The socket has long been described by lower-limb prosthesis users as the most important consideration in their satisfaction with a lower-limb prosthesis.1,4,5 Its purpose is to transfer loads under both static and dynamic conditions with minimal movement between the limb and the prosthesis. Pressure distribution within the socket is an essential component to the comfort and function of the individual using a transtibial prosthesis. Ill-fitting sockets can lead to dermatologic concerns, injury to the limb, and decreased prosthetic utilization. The functional comfort of a transtibial prosthesis is dependent upon a number of interrelated factors including socket type and fit, interface materials, and suspension approaches.

For many decades, the standard of care for transtibial sockets was the joint-and-corset model in which the load-bearing forces were split between the socket and a thigh corset. Confining weight-bearing forces to the transtibial socket was not commonly performed until the introduction and popular acceptance of the patellar tendon bearing (PTB) socket in the 1950s.6 This approach is characterized by localized loading in load-tolerant areas and localized reliefs in areas that are generally intolerant to localized pressure. In the 1990s, the total surface bearing (TSB) socket was introduced in which the entire surface of the transtibial limb is used for load bearing.7,8 The efficacy of the latter appears to be enhanced by the integration of viscoelastic interface liners fabricated from a range of elastic materials including silicone, urethane, and other gel-like substances.9,10 Modern prosthetic sockets are generally a combination of PTB and TSB principles.11

For many years, the interface options worn between the limb and the socket were confined to fabric fitting socks and various foam materials. More recently, the viscoelastic materials mentioned previously have been exploited for their cushioning and ability to integrate suspension. As the interface materials in modern transtibial prosthetic solutions are often integral with suspension of the device, it is difficult to examine these two variables discretely.

With the introduction of the PTB socket design, a number of anatomically based suspension mechanisms were used, including supracondylar socket contours and cuff-strap suspension. The introduction of the TSB socket was largely concurrent with the development of silicone suction suspension and the Icelandic roll-on silicone socket (ICEROSS).9,10 Modern suspension systems connect the residual limb to the socket using a locking silicone liner with a distal pin-lock mechanism, through the creation of a suction environment by internal or external sealing sleeves or rings and through active vacuum where the negative pressure within the suction socket is actively elevated and maintained by an external vacuum component.12

After transtibial amputation, successful prosthetic rehabilitation requires the development of a comprehensive socket strategy inclusive of a socket design, interface materials, and suspension strategy. The most common variants in these design elements are described in Table 1.

Table 1

Table 1

Clinical practice guidelines (CPGs) are increasingly common in health care, with the Federal Agency for Healthcare Research and Quality (AHRQ) now housing over 1700 practice guidelines in its National Guideline Clearinghouse.13 Yet, the field of orthotics and prosthetics is underrepresented in this area, with only a single CPG listed in the AHRQ database. Encouragingly, the field has begun to develop and publish practice guidelines across a range of care episodes including the management of plagiocephaly,14 postoperative care following transtibial amputation,15 prosthetic foot selection for individuals with lower-limb amputation,16 prescribing guidelines for microprocessor-controlled prosthetic knees in South East England,17 and a two-part “Dutch evidence-based guidelines of amputation and prosthetics of the lower extremity.”18,19

The scope and depth of CPGs is variable, with direct implications on their resultant clinical relevance and ultimate incorporation into practice. The current effort is modeled after the CPGs of the American College of Physicians,20 with necessary adaptations to accommodate the emerging evidence base of orthotic and prosthetic care. The stated goals of this approach are to “provide clinicians with clinical-based guidelines based upon the best available evidence; to make recommendations on the basis of that evidence; to inform clinicians of when there is no evidence; and finally, to help clinicians deliver the best health care possible.”20(pp194)

Clinical utility is of paramount importance in this effort, culminating in a small number of succinct, actionable evidence-based recommendations.21 Notably, within this framework, although the resultant CPGs represent a comprehensive overview of available literature, deficits in the available literature preclude CPGs within this framework from providing comprehensive clinical guidance.

The purpose of this guideline is to present the available evidence on definitive transtibial socket design options, interface considerations, and suspension variations. The target audience for this guideline includes prosthetists, surgeons, physicians, therapists, case managers, and policy makers. The target patient population comprises individuals with transtibial amputation due to traumatic, dysvascular, or alternate etiologies.

Back to Top | Article Outline

METHODS

A Medline search was conducted on May 2, 2017, to locate published secondary knowledge sources of evidence statements within the published literature. The following search terms were used: ((prosth*) AND transtibial) AND (socket OR suspension OR interface) AND (systematic review OR meta-analysis). This search originally yielded 17 abstracts. Of these, 9 articles were identified as secondary knowledge sources (i.e., meta-analysis, systematic review, or scoping review) that synthesized published findings of primary knowledge related to transtibial socket design, interface, and suspension.3,11,22–28 Two additional publications meeting this standard were referenced within the selected literature and included for consideration and analysis.29,30 Collectively, the 11 identified publications included one systematic review and meta-analysis,3 nine systematic reviews,11,23–28 and a single scoping review.22

In more recent publications, where authors provided explicit evidence statements, these were extracted for subsequent synthesis (Table 2). If explicit evidence statements were not provided, well-supported narrative statements were extracted (Table 3). Statements were confined to areas of clinical utility. Extracted statements are summarized in Tables 2 and 3 and addressed the following key considerations:

Table 2

Table 2

Table 3

Table 3

  • 1. Comparative effectiveness: With regard to socket design, PTB sockets were compared against TSB sockets. Frequently, these comparisons overlapped with interface comparisons, with foam liners (i.e., Pelite) used in conjunction with PTB sockets, whereas elastomeric liners were used in conjunction with TSB sockets. Suspension comparisons were variable but can be generalized as comparisons between anatomic suspension techniques, mechanical locking liner techniques, and suction techniques, with VAS representing an extreme form of suction that has been extensively studied.
  • 2. Benefits of treatments: Potential benefits found in the extracted evidence statements relate to timeliness of prosthetic fitting, enhanced activity levels, patient satisfaction, reduced movement of the residual limb within the socket (i.e., enhanced suspension), mitigation of forces within the socket, stabilization of limb volume, improved comfort, and better gait symmetry.
  • 3. Harms of treatments: Potential harms found in the extracted evidence statements relate to injury to the residual limb secondary to socket forces, discomfort, heat and perspiration, donning difficulties, and system maintenance requirements.
Back to Top | Article Outline

RECOMMENDATIONS

The extracted evidence statements from Tables 2 and 3 were subsequently synthesized into the six recommendations below, comprising the CPG.

Recommendation 1: The static and dynamic pressure distribution of the residual limb within the socket are essential considerations in patient comfort, function, and well-being.

The socket has consistently been described by lower-limb prosthesis users as the most important consideration in their satisfaction with a lower-limb prosthesis.1,4,5 When present, dissatisfaction with a transtibial prosthesis is frequently caused by strains, injuries, and discomfort associated with fit of the residual limb within the socket.11 Research has shown that interface liners can help distribute loading and reduce pain.29 The challenge of maintaining a congruent fit is exacerbated by changes to the residual limb that can be difficult to predict or control.11 In addition to the immediate impacts of socket fit on the user’s comfort and the health of the residual limb, the fit of the socket over the limb affects biomechanical variables of function and performance.11

Recommendation 2: Total surface bearing sockets are indicated to decrease fitting times and enable higher activity levels.

Compared with PTB sockets, TSB sockets may lead to greater activity levels, fewer pressure problems, and improved satisfaction among active prosthesis users,25 a finding epitomized in the work of Yigiter et al.31 who cite increased gait symmetry, velocity, cadence, and balance with TSB sockets. This statement is made with a recognition that, within the published evidence, TSB sockets have generally been fabricated over elastic liner interfaces, whereas PTB sockets have generally been fabricated over foam interfaces, and the respective contributions of socket design, interface, and suspension cannot be reasonably inferred from current literature. The generalized statement of the benefits of TSB sockets is countered by the observations of a single small trial of 13 subjects who reported increased wearing time and activity with PTB sockets compared with TSB sockets, an observation similarly confounded by the different interfaces and suspension methods used with each socket design type.32

From an economic standpoint, although PTB sockets have a lower initial cost, this is offset by the need for patients to spend up to three times longer in the fitting process to achieve a satisfactory socket fit,22 observations supported by two unrelated clinical trials.33,34 Highsmith et al.22 summarized that these additional clinic visits, which require increased time commitments and travel costs as well as the risk of potential complications, ultimately increase latent costs of PTB sockets. Conversely, TSB sockets have a higher initial procurement cost, but result in fewer associated visits.22

Recommendation 3: Compared with traditional foam-based interfaces, viscoelastic interface lines are indicated to decrease dependence on walking aids, improve suspension, improve load distribution, decrease pain, and increase comfort.

Systematic reviews of existing clinical studies suggest viscoelastic interface liners offer clinical improvements relative to traditional PTB socket interfaces (i.e., foam and fabric). These improvements include decreased reliance on walking aids, improved load distributions against the residual limb, decreased pain, and increased comfort.3,30 These benefits were largely identified in early clinical trials with modest to large study populations of 27 to 83 subjects and included improved walking function,35–37 decreased reliance on upper-limb walking aids,33,36 decreased pain,37,38 and improved comfort.36–38

These benefits are offset by reports of difficulties in donning and doffing experienced by some users27 and a temporary increase in perspiration relative to that experienced within foam and fabric interfaces.27 The relative difficulty of donning viscoelastic interface liners has been inconsistent with early trials citing mixed user experiences.35,37,38 Temporary increases in perspiration with elastic liners has been reported with greater regularity.25,35,37,38 Reviewers have been critical of the quality of research related to transtibial liners and suspension, summarizing that there is insufficient research on user experience to inform specific interface recommendations.24,29,30

Recommendation 4: Among modern suspension options, vacuum-assisted suspension (VAS) sockets permit the least amount of pistoning within the socket, followed by suction suspension, and then pin-lock suspension. The traditional suspension options of supracondylar, cuff, and sleeve suspension provide comparatively compromised suspension.

Kahle et al. described agreement between two high-quality level 2 studies39,40 and one low-quality study,41 offering grade B evidence that VAS reduces movement of the residual limb within the socket.28 When study findings are aggregated, VAS sockets allow the least amount of movement between the residual limb and the socket. Progressively greater socket displacement is experienced with suction sockets without external vacuum assistance and locking liner suspension.26,27 These modern systems provide improved suspension relative to the historical standards of sleeve suspension and supracondylar suspension.3,26 However, because of the additional considerations associated with suspension variants, there is no single suspension system currently viewed as the standard for all individuals with transtibial amputation.27

Recommendation 5: VAS sockets are indicated to decrease daily limb volume changes while facilitating more favorable pressure distribution during gait.

VAS sockets have been studied extensively in recent years, culminating in a well-defined set of potential benefits associated with this socket-suspension system. These benefits include decreases in daily volume changes and in the peak positive pressures experienced during stance,23,28 as well as the maintenance of a better socket fit, improved mobility, comfort, stability, proprioception, overall satisfaction, prosthetic function, and quality of life.23

In their systematic review on VAS sockets, Kahle et al. asserted that VAS sockets increase volume, whereas non-VAS sockets reduce residual limb volume, citing two studies representing level 2 evidence.28 This finding was also asserted in other systematic reviews.3,26,27 This tendency toward limb volume increases is thought to occur as a result of increased negative pressures during swing phase in VAS prostheses.42,43

Kahle et al. also evidenced two high-quality studies41,42 representing level 2 evidence that VAS sockets favorably affect pressure distribution on the residual limb,28 an observation echoed by a similar level 2 evidence statement by Highsmith et al.3 and found in the assertions of Safari et al. that VAS sockets seem to affect residual limb health positively compared with other socket designs and that VAS sockets “seem to improve gait symmetry more than other socket designs.”26

The effect of VAS sockets on the associated constructs of mobility, balance, and function has been viewed differently by different reviewers. Gholizedeh et al.23 asserted that VAS socket systems improve mobility. Kahle et al. also cite two level 2 studies demonstrating improvements in the specific functional areas of spatiotemporal gait39 and balance confidence,44 but also note a third level 2 study reporting a decrease in activity with the use of VAS sockets.40

The relationship between favorable pressure distribution, skin irritation, and wound healing has been viewed differently by different authors. Although”” Gholizedeh suggested that “vacuum systems may reduce skin irritation, reduce pain, and assist in wound healing,”23 Kahle et al. asserted that, “…no evidence exists to support the notion that a prosthesis can assist in healing wounds with or without VAS.”28 Synthesis between these two views is found in a recognition that reduced pistoning reasonably reduces shearing forces which, in turn, reduces the incidence of skin perturbation and pain. Arresting the movement of the limb within the socket may reduce irritation over both healthy and ulcerated tissues, permitting granulation and healing of existing wounds.28

Recommendation 6: VAS sockets require both awareness and compliance on the part of the end user and are not universally indicated.

Despite the established benefits associated with VAS, it is not universally indicated. Gholizedeh et al. summarized succinctly that “…some patients prefer pin-lock systems to vacuum…,” whereas others reduce their activity in VAS.23 It has been suggested that the attention and skills needed for donning a VAS prosthesis may be difficult for some individual with amputation.23 In support of this contention, authors have reported upon the possibility of VAS systems creating skin blisters when worn improperly.40,45 Consistent with these reports, subject matter expert consensus affirms that vacuum systems require both careful clinical evaluation, can cause blistering if not worn properly, and require that the patient has sufficient cognitive ability to know what to watch for and how to fix problems.23 Further, it has been observed VAS requires more maintenance than other suspension systems,23 a reality that should also be weighed when considering its use.

Back to Top | Article Outline

INCONCLUSIVE AREAS OF EVIDENCE

Although the recommendations above summarize the best available evidence, limitations to this evidence base result in several areas of inconclusive findings. Foremost among these is that the related elements of socket design, interface materials, and suspension are largely integral to one another, precluding a precise understanding of their individual contributions to comfort and function.

Note: Clinical practice guidelines are “guides” only and may not apply to all patients and all clinical situations. Thus, they are not intended to replace clinical judgment but rather to supplement clinical practice decision making.

Back to Top | Article Outline

REFERENCES

1. Dillingham TR, Pezzin LE, MacKenzie EJ, Burgess AR. Use and satisfaction with prosthetic devices among persons with trauma-related amputations: a long-term outcome study. Am J Phys Med Rehabil 2001;80:563–571.
2. Ziegler-Graham K, MacKenzie EJ, Ephraim PL, et al. Estimating the prevalence of limb loss in the United States: 2005 to 2050. Arch Phys Med Rehabil 2008;89(3):422–429.
3. Highsmith MJ, Kahle JT, Miro RM, et al. Prosthetic interventions for people with transtibial amputation: systematic review and meta-analysis of high-quality prospective literature and systematic reviews. J Rehabil Res Devel 2016;52:157–184.
4. Legro MW, Reiber G, del Aguila M, et al. Issues of importance reported by persons with lower limb amputations and prostheses. J Rehabil Res Dev 1999;36(3):155–163.
5. Klute GK, Kantor C, Darrouzet C, et al. Lower-limb amputee needs assessment using multistakeholder focus-group approach. J Rehabil Res Dev 2009;46(3):293–304.
6. Radcliffe CW, Foort J, Inman VT, Eberhart H. The patellar-tendon-bearing below-knee prosthesis. Biomechanics Laboratory University of California.
7. Staats TB, Lundt J. The UCLA total surface bearin gsocution below-knee prosthesis. Clin Prosthet Orthot 1987;11(3):118–130.
8. Sewell P, Noroozi S, Vinney J, Andrews S. Developments in the trans-tibial prosthetic socket fitting process: a review of past and present research. Prosthet Orthot Int 2000;24:97–107.
9. Fillauer CE, Pritham CH, Fillauer KD. Evolution and development of the Silicone Suction Socket (3S) for below-knee prostheses. J Prosthet Orthot 1989;1:92–103.
10. Kristensson O. The ICEROSS concept: a discussion of a philosophy. Prosthet Orthot Int 1993;17:49–55.
11. Pirouzi G, Abu Osman NA, Eshraghi A, et al. Review of the socket design and interface pressure measurement for transtibial prosthesis. ScientificWorldJournal 2014;2014:849073.
12. Childers WL, Wurdeman SR. Transtibial amputation: prosthetic management. In: Krajbich JI, Pinzur MS, Potter BK, Stevens PM, eds. Atlas of Amputations and Limb Deficiencies: Surgical, Prosthetic, and Rehabilitation Principles. 4th Ed. Rosemont, IL: American Academy of Orthopedic Surgeons; 2015:493–508.
13. US Department of Health and Human Services; Agency for Healthcare Quality and Research; National Guideline Clearinghouse. Accessed at: https://www.guideline.gov/browse/clinical-specialty on 9/8/2017.
14. Lin RS, Stevens PM, Wininger M, Castiglione CL. Orthotic management of deformational plagiocephaly: consensus clinical standards of care. Cleft Pal Craniofac J 2016;53(4):394–403.
15. Stevens P, Rheinstein J, Campbell J. Acute postoperative care of the residual limb following transtibial amputation: a clinical practice guideline. Arch Phys Med Rehabil 2016;10:e21.
16. Stevens P, Rheinstein J, Wurdeman S. Prosthetic foot selection for individuals with lower limb amputation: a clinical practice guideline. Arch Phys Med Rehabil 2016;10:e21–e22.
17. Sedki I, Fisher K. Developing prescribing guidelines for microprocessor-controlled prosthetic knees in the South East England. Prosthet Orthot Int 2015;39(3):250–254.
18. Geertzen J, van der Linde H, Rosenbrand K, et al. Dutch evidence-based guidelines for amputation and prosthetics of the lower extremity: amputation surgery and postoperative management. Part 1. Prosthet Orthot Int 2015;39(5):351–360.
19. Geertzen J, van der Linde H, Rosenbrand K, et al. Dutch evidence-based guidelines for amputation and prosthetics of the lower extremity: rehabilitation process and prosthetics. Part 2. Prosthet Orthot Int 2015;39(5):361–371.
20. Qaseem A, Snow V, Owens DK, et al. The development of clinical practice guidelines and guidance statements of the American College of Physicians: Summary of Methods. Ann Intern Med 2010;153:194–199.
21. Qaseem A, Humphrey LL, Forciea MA, et al. Treatment of pressure ulcers: a clinical practice guideline from the American College of Physicians. Ann Intern Med 2015;162:370–379.
22. Highsmith MJ, Kahle JT, Lewandowski A, et al. Economic evaluations of interventions for transtibial amputees: a scoping review of comparative studies. Technol Innov 2016;18:85–98.
23. 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.
24. Richardson A, Dillon MP. User experience of transtibial prosthetic liners: a systematic review. Prosthet Orthot Int 2017;41:6–18.
25. Safari MR, Meier MR. Systematic review of effects of current transtibial prosthetic socket designs—Part 1: qualitative outcomes. J Rehabil Res Dev 2015;52:491–508.
26. Safari MR, Meier MR. Systematic review of effects of current transtibial prosthetic socket designs—Part 2: quantitative outcomes. J Rehabil Res Dev 2015;52:509–526.
27. Gholizadeh H, Abu Osman NA, Eshraghi A, et al. Transtibial prosthesis suspension systems: systematic review of literature. Clin Biomech (Bristol, Avon) 2014;29:87–97.
28. Kahle JT, Orriola JJ, Johnston W, Highsmith MJ. The effects of vacuum-assisted suspension on residual limb physiology, wound healing, and function: a systematic review. Tech Innov 2014;15(4):333–341.
29. Klute G, Glaister BC, Berge JS. Prosthetic liners for lower limb amputees: a review of the literature. Prosthet Orthot Int 2010;34:146–153.
30. Baars EC, Geertzen JH. Literature review of the possible advantages of silicon liner socket use in trans-tibial prostheses. Prothet Orthot Int 2005;29(1):27–37.
31. Yigiter K, Sener G, Bayar K. Comparison of the effects of patellar tendon bearing and total surface bearing sockets on prosthetic fitting and rehabilitation. Prosthet Orthot Int 2002;26(3):206–212.
32. Coleman KL, Boone DA, Laing LS, et al. Quantification of prosthetic outcomes: elastomeric gel liner with locking pin suspension versus polyethylene foam liner with neoprene sleeve suspension. J Rehabil Res Dev 2004;41(4):591–502.
33. Datta D, Harris I, Heller B, et al. Gait, cost and time implications for changing from PTB to ICEX ® sockets. Prosthet Orthot Int 2004;28(2):114–120.
34. Selles RW, Janssens PJ, Jongenengel CD, Bussmann JB. A randomized controlled trial comparing functional outcome and cost efficiency of a total surface-bearing socket versus a conventional patellar tendon-bearing socket in transtibial amputees. Arch Phys Med Rehabil 2005;86(1):154–161.
35. Cluitmans J, Geboers M, Deckers J, Rings F. Experiences with respect to the ICEROSS system for transt-tibal prosthesis. Prosthet Orthot Int 1994;18:78–83.
36. Dasgupta AK, McCluskie PJ, Patel VS, Robins L. The performance of the ICEROSS prostheses amongst transtibial amputees with a special reference to the workplace—a preliminary study. Icelandic Roll on Silicone Socket. Occup Med (Lond) 1997;47:228–236.
37. Hachisuka K, Dozono K, Ogata H, et al. Total surface bearing below-knee prosthesis: advantages, disadvantages, and clinical implications. Arch Phys Med Rehabil 1998;79:783–789.
38. Datta D, Vaidya SK, Howitt J, Gopalan L. Outcome of fitting an ICEROSS prosthesis: views of trans-tibial amputees. Prosthet Orthot Int 1996;20:111–115.
39. Board WJ, Street GM, Caspers C. A comparison of trans-tibial amputee suction and vacuum socket conditions. Prosthet Orthot Int 2001;25(3):202–209.
40. Klute GK, Berge JS, Biggs W, et al. 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.
41. Kahle JT, Highsmith MJ. Transfemoral sockets with vacuum assisted suspension comparison of hip kinematics, socket position, contact pressure and preference: ischial containment versus brimless. J Rehabil Res Dev 2013;50(9):1241–1252.
42. Beil TL, Street GM, Covey SJ. Interface pressures during ambulation using suction and vacuum-assisted prosthetic sockets. J Rehabil Res Dev 2002;39:693–700.
43. Sanders JE, Fatone S. Residual limb volume change: systematic review of measurement and management. J Rehabil Res Dev 2011;48:949–986.
44. Ferraro C. Outcomes study of transtibial amputees using elevated vacuum suspension in comparison with pin suspension. J Prosthet Orthot 2011;23(2):78–81.
45. Traballesi M, Delussu AS, Fusco A, et al. Residual limb wounds or ulcers heal in transtibial amputees using an active suction socket system. A randomized controlled study. Eur J Phys Rehail 2012;48:613–623.
Keywords:

clinical practice guideline; transtibial; socket; interface; suspension; suction; vacuum; total surface bearing; patellar tendon bearing, liner

© 2019 by the American Academy of Orthotists and Prosthetists.