9th

Australasian Biomechanics Conference, University of Wollongong, Australia, 30 Nov – 2 Dec 2014

REPEATABILITY OF STATIC LOAD BEARING EXERCISES DURING REHABILITATION OF INDIVIDUALS WITH TRANSFEMORAL AMPUTATION FITTED WITH OSSEOINTEGRATED IMPLANT

Sofie Vertriest1, Laurent Frossard

2,3

1 Ghent University Hospital, Belgium

2 University of the Sunshine Coast, Maroochydore, QLD, Australia

3 Queensland University of Technology, Brisbane, QLD, Australia

email: sofie.vertriest@uzgent.be

Vertriest S, Frossard L. Repeatability of static load bearing exercises during rehabilitation of individuals with

transfemoral amputation fitted with osseointegrated implant . IX Australasian Biomechanics Conference (ABC9). 2014.

Wollongong, Australia. p 79

INTRODUCTION Bone-anchored prostheses, relying on implants to

attach the prosthesis directly to the residual skeleton, are the ultimate resort for patients with transfemoral amputations (TFA) experiencing severe socket discomfort. The first patient receiving a bone-anchored prosthesis underwent the surgery in 1990 in the Sahlgrenska University Hospital (Sweden).

To date, there are two commercially available implants: OPRA (Integrum, Sweden) and ILP (Orthodynamics, Germany).

[1, 2] The key to success to this

technique is a firm bone-implant bonding, depending on increasing mechanical stress applied daily during load bearing exercises (LBE). The loading data could be analysed through different biomechanical variables.

[3-6]

The intra-tester reliability of these exercises will be presented here.

Moreover the effect of increase of loading, axes of application of the load and body weight as well as the difference between force and moment variables will be discussed. METHODS

Eleven individuals with unilateral transfemoral amputation fitted with an OPRA osseointegrated implant participated in this study. They performed five trials in four loading conditions (10kg, 20kg, 40 kg and a maximum depending on the body weight).

[7, 8]

The forces and moments on the three axes of the implant were measured directly with a six-channel commercial transducer embedded in a short pylon (Figure 1).

[7-19] Patients monitor the load applied by looking at a

bathroom scale, getting information only on the load applied on the vertical axis.

Reliability of the loading variables was assessed using intraclass correlation coefficients (ICCs), standard error of measurement values (SEMs) and %SEM values.

RESULTS The ICCs of all variables ranged between 0.947 and 1 and the %SEM values ranged between 0 and 87.07%. The lowest ICC values and the highest %SEM values were found for the MLG and MML for the higher loads.

Figure 1: Overview of the apparatus used to monitor the load prescribed including the single-axis strain gauge (A) that was embedded in a support frame (B) and connected to a LCD display (C). DISCUSSION The %SEM is slightly higher for the moments than for the forces, especially for the MLG and MML in the higher loads (40kg and max load) indicating a slight decrease in the reliability for the moment on the long and mediolateral axis for the higher loads. Apart from these exceptions, the progression of the load prescribed, the axes of application and the body weight did have only limited impact on the reliability

CONCLUSIONS The results indicate an overall high reliability between the loading conditions with little to no impact of the progression of the load prescribed, the axes of application and the body weight.

9th

Australasian Biomechanics Conference, University of Wollongong, Australia, 30 Nov – 2 Dec 2014

REFERENCES 1. Hagberg, K. and R. Branemark, One hundred patients

treated with osseointegrated transfemoral amputation prostheses-rehabilitation perspective. J Rehabil Res Dev, 2009. 46(3): p. 331-44.

2. Aschoff, H.H., R.E. Kennon, J.M. Keggi, and L.E. Rubin, Transcutaneous, distal femoral, intramedullary attachment for above-the-knee prostheses: an endo-exo device. J Bone Joint Surg Am, 2010. 92 Suppl 2(Supplement 2): p. 180-6.

3. Beaulieu, P., S. Vertriest, and L. Frossard. Description of body posture during static load bearing exercises for individuals with transfemoral amputation fitted with bone-anchored prosthesis. in 2013 O&P World Congress. 2013. Orlando, USA.

4. Vertriest, S., P. Coorevits, and L. Frossard. Static load bearing exercises during rehabilitation of individuals with transfemoral amputation fitted with osseointegrated implant: Load compliance. in 2013 O&P World Congress. 2013. Orlando, USA.

5. Vertriest, S., P. Coorevits, and L. Frossard. Static load bearing exercises during rehabilitation of individuals with transfemoral amputation fitted with osseointegrated implant: Kinetic analysis. in 14th World Congress of the International Society of Prosthetics and Orthotics (ISPO). 2013. Hyderabad, India.

6. Vertriest, S., P. Coorevits, and L. Frossard. Load bearing exercises and functional outcome of individuals with transfemoral amputation fitted with OPRA fixation. in 4th international conference in Advances in Orthopaedic osseintegration - Orthopaedic Surgical Osseointegration Society. 2012. San Francisco, USA.

7. Vertriest, S., P. Coorevits, K. Hagberg, R. Branemark, E. Haggstrom, G. Vanderstraeten, and L. Frossard, Static Load Bearing Exercises of Individuals With Transfemoral Amputation Fitted With an Osseointegrated Implant: Reliability of Kinetic Data. IEEE Trans Neural Syst Rehabil Eng, 2014. In press.

8. Frossard, L., D.L. Gow, K. Hagberg, N. Cairns, B. Contoyannis, S. Gray, R. Branemark, and M. Pearcy, Apparatus for monitoring load bearing rehabilitation exercises of a transfemoral amputee fitted with an osseointegrated fixation: a proof-of-concept study. Gait Posture, 2010. 31(2): p. 223-8.

9. Frossard, L., J. Beck, M. Dillon, M. Chappell, and J.H. Evans, Development and preliminary testing of a device for the direct measurement of forces and moments in the prosthetic limb of transfemoral amputees during activities of daily living. Journal of Prosthetics and Orthotics, 2003. 15(4): p. 135-142.

10. Frossard, L., L. Cheze, and R. Dumas, Dynamic input to determine hip joint moments, power and work on the prosthetic limb of transfemoral amputees: ground reaction vs knee reaction. Prosthet Orthot Int, 2011. 35(2): p. 140-9.

11. Frossard, L., K. Hagberg, E. Haggstrom, and R. Branemark, Load-relief of walking aids on osseointegrated fixation: instrument for evidence-based practice. IEEE Trans Neural Syst Rehabil Eng, 2009. 17(1): p. 9-14.

12. Frossard, L., K. Hagberg, E. Häggström, D.L. Gow, R. Brånemark, and M. Pearcy, Functional Outcome of Transfemoral Amputees Fitted With an Osseointegrated Fixation: Temporal Gait Characteristics. JPO Journal of Prosthetics and Orthotics, 2010. 22(1): p. 11-20.

13. Frossard, L., E. Haggstrom, K. Hagberg, and P. Branemark, Load applied on a bone-anchored transfemoral prosthesis: characterisation of prosthetic components – A case study Journal of Rehabilitation Research & Development, 2013. 50(5): p. 619–634.

14. Frossard, L., N. Stevenson, J. Smeathers, E. Haggstrom, K. Hagberg, J. Sullivan, D. Ewins, D.L. Gow, S. Gray, and R. Branemark, Monitoring of the load regime applied on the osseointegrated fixation of a trans-femoral amputee: a tool for evidence-based practice. Prosthet Orthot Int, 2008. 32(1): p. 68-78.

15. Frossard, L., N. Stevenson, J. Sullivan, M. Uden, and M. Pearcy, Categorization of Activities of Daily Living of Lower Limb Amputees During Short-Term Use of a Portable Kinetic Recording System: A Preliminary Study. JPO Journal of Prosthetics and Orthotics, 2011. 23(1): p. 2-11.

16. Frossard, L., R. Tranberg, E. Haggstrom, M. Pearcy, and R. Branemark, Fall of a transfemoral amputee fitted with osseointegrated fixation: loading impact on residuum. Gait & Posture, 2009. 30(Supplement 2): p. S151-S152.

17. Frossard, L.A., Load on osseointegrated fixation of a transfemoral amputee during a fall: Determination of the time and duration of descent. Prosthet Orthot Int, 2010. 34(4): p. 472-87.

18. Frossard, L.A., R. Tranberg, E. Haggstrom, M. Pearcy, and R. Branemark, Load on osseointegrated fixation of a transfemoral amputee during a fall: loading, descent, impact and recovery analysis. Prosthet Orthot Int, 2010. 34(1): p. 85-97.

19. Lee, W.C., L.A. Frossard, K. Hagberg, E. Haggstrom, D.L. Gow, S. Gray, and R. Branemark, Magnitude and variability of loading on the osseointegrated implant of transfemoral amputees during walking. Med Eng Phys, 2008. 30(7): p. 825-833.

REPEATABILITY OF STATIC LOAD BEARING EXERCISES DURING REHABILITATION OF INDIVIDUALS WITH TRANSFEMORAL AMPUTATION FITTED WITH OSSEOINTEGRATED IMPLANT

Sofie Vertriest1, Laurent Frossard2,3

1 Ghent University Hospital, Belgium, 2 University of the Sunshine Coast, Maroochydore, QLD, Australia, 3 Queensland University of Technology, Brisbane, QLD, Australia

INTRODUCTION • Bone-anchored prostheses, relying on implants to attach the

prosthesis directly to the residual skeleton, are the ultimate resort for patients with transfemoral amputations (TFA) experiencing severe socket discomfort. The first patient receiving a bone-anchored prosthesis underwent the surgery in 1990 in the Sahlgrenska University Hospital (Sweden).

• To date, there are two commercially available implants: OPRA (Integrum, Sweden) and ILP (Orthodynamics, Germany). [1,2] The key to success to this technique is a firm bone-implant bonding, depending on increasing mechanical stress applied daily during load bearing exercises (LBE). The loading data could be analysed through different biomechanical variables. [3,4] The intra-tester reliability of these exercises will be presented here.

• Moreover the effect of increase of loading, axes of application of the load and body weight as well as the difference between force and moment variables will be discussed.

METHODS • Participants: Eleven individuals with unilateral transfemoral

amputation fitted with an OPRA osseointegrated implant.

• Trials: five trials in four loading conditions: 10kg, 20kg, 40 kg and a maximum depending on the body weight.

• Measurements: o What: forces and moments on the three axes of the

implant (FML, FAP , FLG ,MML, MAP , MLG ) o How: directly with a six-channel commercial

transducer embedded in a short pylon (Figure 1).[5] o Control: Patients monitor the load applied by looking

at a bathroom scale, gathering information only on the load applied on the vertical axis.

• Statistical analysis: Reliability of the loading variables was

assessed using intraclass correlation coefficients (ICCs), standard error of measurement values (SEMs) and %SEM values.

Figure 1: Overview of the apparatus used to monitor the load prescribed including the single-axis strain gauge (A) that was embedded in a support frame (B) and connected to a LCD display (C).

RESULTS • Mean force applied was:

o 79.03±57.54 N on the mediolateral axis, o 107.86±43.52 N on the anteroposterior axis, o 166.14±22.77 N on the long axis, o 223.97±26.19 N resultant.

• ICCs of all variables ranged between 0.947 and 1. • SEM values ranged between 0 and 87.07%. • The lowest ICC values and the highest %SEM values were found

for the MLG and MML for the higher loads.

DISCUSSION • The %SEM is slightly higher for the moments than for the forces,

especially for the MLG and MML in the higher loads (40kg and max load) indicating a slight decrease in the reliability for the moment on the long and mediolateral axis for the higher loads.

• Apart from these exceptions, the progression of the load prescribed, the axes of application and the body weight did have only limited impact on the reliability.

CONCLUSIONS • Overall high reliability between the loading conditions. • Little to no impact of:

o The progression of the load prescribed, o The axes of application, o The body weight.

REFERENCES • [1] Hagberg K. and R. Brånemark. Journal of Rehabilitation

Research & Development, 43(3): 331-344, 2009. • [2] Aschoff H. et al. The Journal of Bone & Joint Surgery, 92

(Supplement 2): 180-186, 2010. • [3] Vertriest S., Coorevits P., Frossard L. XIVth World Congress of

the ISPO, Hyderabad, India, 2013. • [4] Vertriest S., Coorevits P., Frossard L. OSOS, San Francisco,

USA, 2012. • [5] Frossard. L. et al. Gait and Posture, 31(2): 223-228, 2010.

TO KNOW MORE • Vertriest S, Coorevits P, Hagberg K, Brånemark R, Häggström E,

Vanderstraeten G, Frossard L. Static load bearing exercises of individuals with transfemoral amputation fitted with an osseointegrated implant: Reliability of kinetic data. IEEE Transactions on Neural Systems and Rehabilitation Engineering. 2014. Online First. DOI: 10.1109/TNSRE.2014.2337956

• http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=6856197

SPEAKER’S INFORMATION Laurent Frossard (PhD) • Adjunct Professor at QUT and USC • Director at YourResearchProject • Laurentfrossard@yahoo.com.au • +61 (0)4 1379 5086 • www.laurentfrossard.com