•  
  •  
 

Abstract

Total hip replacement (THR) is one of the most successful orthopedic surgical procedures for replacing a broken hip joint. In THR, wear may occur at the articulating surface of the acetabular cup and the femoral head. In Indonesia, the country with the largest Muslim population in the world, most of the inhabitants do salat (praying) every day. THR users are banned from doing salat for fear it will damage the hip joint prostheses. The previous wear calculation methods on the hip joint prostheses use the gravimetric, coordinate measuring machine (CMM), profiler, and geometric method. The disadvantages of the previous methods are that the geometry of the wear patch and the wear volume are only known at the end of the experiment, so they cannot be used to calculate the specific wear rate values in real time. So far, in every modeling of the hip joint prostheses, the values of the specific wear rate are assumed to be constant. This paper reports on the design modification of a pin-on-ring tribometer that is used to measure the wear volumes in hip joint prostheses. The result shows that modifications of the femoral head holder, reciprocating motion, elastic joint, and extra displacement transducer is needed to get the specific wear rate value. The calculation method to find the delta volume that is the value of displacement less than the displacement minimum (δmin) is based on a graph, while the calculation method to find the delta volume that is the value of displacement that is more than the displacement minimum (δmin) is based on an equation. In the salat test protocol, the longest test time was during the sujud (prostration) motion, which took 1034.17 minutes in the experiment.

Bahasa Abstract

Desain Modifikasi Tribometer Pin-on-Ring untuk Pengukuran Tulang Pinggul Buatan: Studi Kasus pada Gerakan Shalat. Total hip replacement (THR) adalah salah satu solusi bedah ortopedi yang paling sukses untuk mengganti tulang pinggul yang rusak. Dalam THR, aus akan terjadi pada permukaan accetabular cup dan femoral head. Indonesia, negara dengan penduduk muslim terbesar di dunia, kebanyakan penduduknya mengerjakan shalat setiap hari. Pengguna THR dilarang mengerjakan shalat karena dikhawatirkan akan merusak tulang pinggul buatan. Metode perhitungan aus sebelumnya pada tulang pinggul buatan menggunakan metode gravimetric, Coordinate Measuring Machine (CMM), profiller dan geometric. Kekurangan dari metode-metode sebelumnya adalah bentuk aus dan volume aus hanya dapat diketahui ketika pengujiannya selesai, sehingga tidak dapat digunakan untuk menentukan nilai specific wear rate secara kontinyu. Sampai sejauh ini, setiap pemodelan dari tulang pinggul buatan menggunakan nilai spesific wear rate yang konstan. Makalah ini melaporkan desain modifikasi tribometer pin-on-ring untuk mengukur volume aus pada tulang pinggul buatan. Hasil dari penelitian ini menunjukkan bahwa untuk mendapat nilai spesifik wear rate dibutuhkan modifikasi pada femoral head holder, gerak reciprocating, elastic joint, dan penambahan displacement transducer. Metode perhitungan untuk menghitung volume aus dimana perpindahan kurang dari displacement minimum (δmin) menggunakan grafik, sedangkan metode perhitungan untuk menghitung volume aus dimana perpindahan lebih dari displacement minimum (δmin) menggunakan rumus. Dalam prosedur tes untuk gerakan shalat, waktu terpanjang adalah gerakan sujud yang mecapai 1034,17 menit.

References

M.S. Uddin, L.C. Zhang, Wear 301 (2013) 192.

L. Mattei, F. Di Puccio, B. Piccigallo, E. Ciulli, Tribol. Int. 44/5 (2011) 532.

D. Dowson, Wear 190/2 (1995) 171.

D. Dowson, C. Hardaker, M. Flett, G.H. Isaac, J. Arthroplast. 19/8 Suppl. (2004) 118.

H.J. Cho, W.J. Wei, H.C. Kao, C.K. Cheng, Mater. Chem. Phys. 88/1 (2004) 9.

P.J. Firkins, J.L. Tipper, E. Ingham, M.H. Stone, R. Farrar, J. Fisher, J. Biomec. 34/10 (2001) 1291.

E. Saputra, I.B. Anwar, Jamari, E. Van Der Heide, Procedia Eng. 68 (2013) 102.

G.K. Sfantos, M.H. Aliabadi, J. Biomech. 40/2 (2007) 378.

D.J. Schipper, S. Odi-Owei, Tribol. Int. 25/3 (1992) 169.

M. Tuke, A. Taylor, A. Roques, C. Maul, Precis. Eng. 34/4 (2010) 777.

X.Q. Hu, C.M. Han, R.J.K. Wood, Wear 271/11-12 (2011) 2775.

D. Dowson, C. Hardaker, M. Flett, G.H. Isaac, J. Arthroplast. 19/8 Suppl. (2004) 124.

S. Carmignato, M. Spinelli, S. Affatato, E. Savio, Wear 270/9-10 (2011) 584.

Share

COinS
 
 

To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.