ORIGINAL RESEARCH| Volume 103, ISSUE 8, P1515-1523, August 2022

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Comparison of Ischial Containment and Subischial Sockets Effect on Gait Biomechanics in People With Transfemoral Amputation: A Randomized Crossover Trial

Published:March 12, 2022DOI:



      To compare gait biomechanics of the Northwestern University Flexible Sub-Ischial Vacuum (NU-FlexSIV) Socket to the ischial containment (IC) socket.


      Randomized crossover trial with 2, 7-week periods.


      Private prosthetic clinics and university research laboratory.


      A total of 30 enrolled (n=30); 25 participants completed the study with full (n=18) or partial data (n=7).


      Two custom-fabricated sockets (IC and NU-FlexSIV), worn full-time for 7 weeks, with testing at 1, 4, and 7 weeks after socket delivery.

      Main Outcome Measures

      Gait analyses were conducted at 1, 4, and 7 weeks post socket delivery. Differences between sockets in selected gait variables related to hip motion and coronal plane socket stability were assessed.


      For participants with data for both sockets at week 7 (n=19), there were no significant differences in any gait variables between sockets at self-selected normal walking speed. However, when all participants and all study time points were assessed (n=25), there was a significant main effect of socket (P=.013), with prosthetic side sagittal plane hip range of motion being significantly greater for the NU-FlexSIV Socket at self-selected normal walking speed. There were no other significant effects.


      The results suggest that, compared to the IC socket, the NU-FlexSIV Socket did not alter gait biomechanics related to hip motion and coronal plane socket stability in people with unilateral transfemoral amputation.


      List of abbreviations:

      IC (ischial containment), MDC (minimal detectable change), NU-FlexSIV (Northwestern University Flexible Sub-Ischial Vacuum), ROM (range of motion), TFA (transfemoral amputation)
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        • Ziegler-Graham K
        • MacKenzie E
        • Ephraim P
        • et al.
        Estimating the prevalence of limb loss in the United States: 2005 to 2050.
        Arch Phys Med Rehabil. 2008; 89: 422-429
        • Dillingham TR
        • Pezzin LE
        • MacKenzie EJ.
        Limb amputation and limb deficiency: epidemiology and recent trends in the United States.
        South Med J. 2002; 95: 875-883
        • Muller M.
        Transfemoral amputation: prosthetic management. In: Krajbich JI, Pinzur MS, Potter BK, Stevens PM, editors.
        Atlas of amputations and limb deficiencies: surgical, prosthetic and rehabilitation principles. 4th ed. American Academy of Orthopaedic Surgeons, Rosemont, IL2016: 537-554
        • Whiteside S
        • Allen M
        • Bick J
        • et al.
        Practice analysis of certified practitioners in the disciplines of orthotics and prosthetics.
        American Board for Certification in Orthotics and Prosthetics. Alexandria, VA2015
        • Klotz R
        • Colobert B
        • Botino M
        • et al.
        Influence of different types of sockets on the range of motion of the hip joint by the transfemoral amputee.
        Ann Phys Med Rehabil. 2011; 54: 399-410
        • Tranberg R
        • Zugner R
        • Karrholm J.
        Improvements in hip and pelvic motion for patients with osseointegrated trans-femoral prostheses.
        Gait Posture. 2011; 33: 165-168
        • Hagberg K
        • Haggstrom E
        • Uden M
        • et al.
        Socket versus bone-anchored trans-femoral prostheses: hip range of motion and sitting comfort.
        Prosthet Orthot Int. 2005; 29: 153-163
        • Dillingham TR
        • Pezzin LE
        • MacKenzie EJ
        • et al.
        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
        • Pezzin LE
        • Dillingham TR
        • MacKenzie EJ
        • et al.
        Use and satisfaction with prosthetic limb devices and related services.
        Arch Phys Med Rehabil. 2004; 85: 723-729
        • Berke GM
        • Fergason J
        • Milani JR
        • et al.
        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: 361-371
        • 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: 1241-1252
        • Fatone S
        • Caldwell R.
        Northwestern University Flexible Subischial Vacuum Socket for persons with transfemoral amputation: part 1 description of technique.
        Prosthet Orthot Int. 2017; 41: 237-245
        • Kahle J
        • Miro R
        • Ho L
        • et al.
        The effect of the transfemoral prosthetic socket interface designs on skeletal motion and socket comfort: a randomized clinical trial.
        Prosthet Orthot Int. 2020; 44: 145-154
        • Fatone S
        • Caldwell R
        • Angelico J
        • et al.
        Comparison of ischial containment and sub-ischial sockets on comfort, function, quality-of-life and satisfaction with device in persons with unilateral transfemoral amputation: a randomized crossover trial.
        Arch Phys Med Rehabil. 2021; 102: 2063-2073
        • Fatone S
        • Dillon M
        • Stine R
        • et al.
        Coronal plane socket stability during gait in persons with unilateral transfemoral amputation: pilot study.
        J Rehabil Res Dev. 2014; 51: 1217-1228
        • Schuch CM
        • Pritham CH.
        Current transfemoral sockets.
        Clin Orthop Rel Res. 1999; 361: 48-54
        • Dillon M.
        Insights into socket geometry and coronal plane alignment.
        in: Paper presented at 12th World Congress of the International Society for Prosthetics and Orthotics. Vancouver, July 29-August 3, 2007
        • Radcliffe C.
        Functional considerations in the fitting of above-knee prostheses.
        Artif Limbs. 1955; 2: 35-60
        • Pritham CH.
        Biomechanics and shape of the above-knee socket considered in light of the ischial containment concept.
        Prosthet Orthot Int. 1990; 14: 9-21
        • Fatone S
        • Caldwell R.
        Northwestern University Flexible Subischial Vacuum Socket for persons with transfemoral amputation: part 2 description and preliminary evaluation.
        Prosthet Orthot Int. 2017; 41: 246-250
        • Brown S
        • Russell Esposito E
        • Ikeda A
        • et al.
        Evaluation of NU-FlexSIV Socket performance for military service members with transfemoral amputation.
        US Army Med Dep J. 2018; 2-18: 38-47
        • Gailey RS
        • Roach KE
        • Applegate EB
        • et al.
        The Amputee Mobility Predictor: an instrument to assess determinants of the lower-limb amputee's ability to ambulate.
        Arch Phys Med Rehabil. 2002; 83: 613-627
        • Kadaba MP
        • Ramakrishnan HK
        • Wootten ME.
        Measurement of lower extremity kinematics during level walking.
        J Orthop Res. 1990; 8: 383-392
        • Fatone S.
        Challenges in lower-limb orthotic research.
        Prosthet Orthot Int. 2010; 34: 235-237
        • Wilken JM
        • Rodriguez KM
        • Brawner M
        • et al.
        Reliability and minimal detectible change values for gait kinematics and kinetics in healthy adults.
        Gait Posture. 2012; 35: 301-307
        • Meldrum D
        • Shouldice C
        • Conroy R
        • et al.
        Test–retest reliability of three dimensional gait analysis: including a novel approach to visualising agreement of gait cycle waveforms with Bland and Altman plots.
        Gait Posture. 2014; 39: 265-271
        • Kahle JT
        • Highsmith MJ.
        Transfemoral interfaces with vacuum assisted suspension comparison of gait, balance, and subjective analysis: Ischial containment versus brimless.
        Gait Posture. 2014; 40: 315-320