PMID- 9117168
OWN - NLM
STAT- MEDLINE
DCOM- 19970422
LR  - 20190831
IS  - 0263-7103 (Print)
IS  - 0263-7103 (Linking)
VI  - 36
IP  - 1
DP  - 1997 Jan
TI  - The friction of explanted hip prostheses.
PG  - 20-6
AB  - Charnley prostheses, retrieved at revision surgery, were studied to assess the 
      effects of friction on the total hip replacement procedure. Frictional resistance 
      was measured using the Durham hip function simulator under both dry and 
      lubricated conditions. The friction factor values (f) for the explanted 
      prostheses were found to have a non-Gaussian distribution with medians of 0.13 
      [inter-quartile range (IQR) 0.10-0.16] and 0.06 (IQR 0.005-0.08) for dry and 
      lubricated (n = 0.01 Pa s) regimes, respectively. New Charnley prostheses had 
      values of f equal to 0.11 +/- 0.025 and 0.04 +/- 0.01 under the same conditions, 
      and showed no large deviation from a Gaussian distribution. There was found to be 
      a statistically significant difference in the medians of the friction factors for 
      new and retrieved prostheses in the lubricated regime. Ingression of cement into 
      the worn region of the cup was found to increase the friction factor 
      significantly under dry conditions. There was no evidence of an increase in the 
      friction factor or torque for those joints that had a loose socket with respect 
      to those that were fixed at revision. A decrease in the frictional torque against 
      number of cycles undergone by the joint in vivo may indicate that a fatigue-type 
      process may have a role in the loosening of the socket. However, this 
      relationship was found not to be significant for friction measured under 
      lubricated conditions and it seems unlikely that the frictional torque generated 
      in this type of prosthesis will contribute significantly to the long-term 
      loosening of the socket.
FAU - Hall, R M
AU  - Hall RM
AD  - Centre for Biomedical Engineering, University of Durham.
FAU - Unsworth, A
AU  - Unsworth A
FAU - Wroblewski, B M
AU  - Wroblewski BM
FAU - Siney, P
AU  - Siney P
FAU - Powell, N J
AU  - Powell NJ
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - England
TA  - Br J Rheumatol
JT  - British journal of rheumatology
JID - 8302415
SB  - IM
MH  - Adult
MH  - Aged
MH  - Female
MH  - Friction
MH  - Hip/*surgery
MH  - *Hip Prosthesis
MH  - Humans
MH  - Male
MH  - Materials Testing
MH  - Middle Aged
MH  - Time Factors
MH  - Torque
EDAT- 1997/01/01 00:00
MHDA- 1997/01/01 00:01
CRDT- 1997/01/01 00:00
PHST- 1997/01/01 00:00 [pubmed]
PHST- 1997/01/01 00:01 [medline]
PHST- 1997/01/01 00:00 [entrez]
AID - 10.1093/rheumatology/36.1.20 [doi]
PST - ppublish
SO  - Br J Rheumatol. 1997 Jan;36(1):20-6. doi: 10.1093/rheumatology/36.1.20.