In Vivo Estimation of the Coefficient of Friction between Extrinsic Flexor Tendons and Surrounding Structures in the Carpal Tunnel

1987 ◽  
Vol 31 (3) ◽  
pp. 323-324 ◽  
Author(s):  
Thomas J. Albin
Keyword(s):  
Coefficient Of Friction ◽  
Carpal Tunnel ◽  
Frictional Coefficient ◽  
Flexor Tendons ◽  
In Vivo Measurement ◽  
The Coefficient Of Friction

It has been suggested that the coefficient of friction between the finger flexor tendons and the structures over which they slide is normally quite small, but increases with irritation of the tendon. This paper utilizes a belt and pulley model of the wrist in the in vivo measurement of the frictional coefficient. An estimated value of 0.12 for the frictional coefficient was obtained from a sample of five symptom free subjects.

IN VIVO MEASUREMENT OF CARPAL TUNNEL PRESSURE IN FUNCTIONING HAND

1993 ◽  
Vol 86 (Supplement) ◽  
pp. 75
Author(s):  
Houshang Seradge ◽  
Gregory Y. Jia ◽  
Willis Owens
Keyword(s):  
Carpal Tunnel ◽  
In Vivo Measurement

In vivo measurement of carpal tunnel pressure in the functioning hand

1995 ◽  
Vol 20 (5) ◽  
pp. 855-859 ◽  
Author(s):  
Houshang Seradge ◽  
Yi-Cheng Jia ◽  
Willis Owens
Keyword(s):  
Carpal Tunnel ◽  
In Vivo Measurement

scholarly journals Wax-oil lubricants to reduce the shear between skin and PPE

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Kian Kun Yap ◽  
Manoj Murali ◽  
Zhengchu Tan ◽  
Xue Zhou ◽  
Luli Li ◽  
...  
Keyword(s):  
Olive Oil ◽  
Coefficient Of Friction ◽  
Static Friction ◽  
Mineral Oil ◽  
The Coefficient Of Friction ◽  
Friction Measurements ◽  
Lubricant Application ◽  
Static Coefficient Of Friction

AbstractProlonged use of tight-fitting PPE, e.g., by COVID-19 healthcare workers leads to skin injuries. An important contributor is the shear exerted on the skin due to static friction at the skin-PPE interface. This study aims to develop an optimised wax-oil lubricant that reduces the friction, or shear, in the skin-PPE contact for up to four hours. Lubricants with different wax-oil combinations were prepared using beeswax, paraffin wax, olive oil, and mineral oil. In-vivo friction measurements involving seven participants were conducted by sliding a polydimethylsiloxane ball against the volar forearms to simulate the skin-PPE interface. The maximum static coefficient of friction was measured immediately and four hours after lubricant application. It was found that the coefficient of friction of wax-oil lubricants is mainly governed by the ratio of wax to oil and the thermal stability and morphology of the wax. To maintain long-term lubricity, it is crucial to consider the absorption of oil into the PPE material. The best performing lubricant is a mixture of 20 wt% beeswax, 40 wt% olive oil, and 40 wt% mineral oil, which compared to unlubricated skin, provides 87% (P = 0.0006) and 59% (P = 0.0015) reduction in instantaneous and 4-h coefficient of friction, respectively.

scholarly journals Wax-Oil Lubricants to Reduce the Shear Between Skin and PPE

2021 ◽  
Author(s):  
Kian Kun Yap ◽  
Manoj Murali ◽  
Zhengchu Tan ◽  
Xue Zhou ◽  
Luli Li ◽  
...  
Keyword(s):  
Olive Oil ◽  
Coefficient Of Friction ◽  
Static Friction ◽  
Mineral Oil ◽  
The Coefficient Of Friction ◽  
Friction Measurements ◽  
Lubricant Application ◽  
Static Coefficient Of Friction

Abstract Prolonged use of tight-fitting PPE, e.g., by COVID-19 healthcare workers leads to skin injuries. An important contributor is the shear exerted on the skin due to static friction at the skin-PPE interface. This study aims to develop an optimised wax-oil lubricant that reduces the friction, or shear, in the skin-PPE contact for up to four hours. Lubricants with different wax-oil combinations were prepared using beeswax, paraffin wax, olive oil, and mineral oil. In-vivo friction measurements involving seven participants were conducted by sliding a polydimethylsiloxane ball against the volar forearms to simulate the skin-PPE interface. The maximum static coefficient of friction was measured immediately and four hours after lubricant application. It was found that the coefficient of friction of wax-oil lubricants is mainly governed by the ratio of wax to oil and the thermal stability and morphology of the wax. To maintain long-term lubricity, it is crucial to consider the absorption of oil into the PPE material. The best performing lubricant is a mixture of 20 wt% beeswax, 40 wt% olive oil, and 40 wt% mineral oil, which compared to unlubricated skin, provides 87% (P = 0.0006) and 59% (P = 0.0015) reduction in instantaneous and 4-hour coefficient of friction, respectively.

Forces Transmitted Along Human Flexor Tendons During Passive and Active Movements of the Fingers

2004 ◽  
Vol 29 (4) ◽  
pp. 386-389 ◽  
Author(s):  
E. S. POWELL ◽  
I. A. TRAIL
Keyword(s):  
Carpal Tunnel ◽  
Decompression Surgery ◽  
Great Caution ◽  
Flexor Tendons ◽  
Active Flexion ◽  
The Mean ◽  
Range Of Values

The in vivo forces in human digital flexor tendons were determined in 33 patients undergoing a carpal tunnel decompression surgery using a newly developed device. The tendons were tested in passive and active flexion, and flexing against resistance of up to 500 g. Forces in the range of 0.2 to 50 N were noted. Whilst the mean of these forces remained below the force normally required to dehisce a fresh modified Kessler repair, the range of values was such that we would only recommend early movement with great caution and under supervision.

Experimental Investigation of aluminum doping crumb rubber/epoxy composite in reciprocating motion

2015 ◽  
Vol 3 ◽  
pp. 1
Author(s):  
Goutam Chandra Karar ◽  
Nipu Modak
Keyword(s):  
Experimental Investigation ◽  
Coefficient Of Friction ◽  
Epoxy Composite ◽  
Normal Load ◽  
Crumb Rubber ◽  
The Other ◽  
Reciprocating Motion ◽  
Molding Process ◽  
Friction Tester ◽  
The Coefficient Of Friction

The experimental investigation of reciprocating motion between the aluminum doped crumb rubber /epoxy composite and the steel ball has been carried out under Reciprocating Friction Tester, TR-282 to study the wear and coefficient of frictions using different normal loads (0.4Kg, 0.7Kgand1Kg), differentfrequencies (10Hz, 25Hz and 40Hz).The wear is a function of normal load, reciprocating frequency, reciprocating duration and the composition of the material. The percentage of aluminum presents in the composite changesbut the other components remain the same.The four types of composites are fabricated by compression molding process having 0%, 10%, 20% and 30% Al. The effect of different parameters such as normal load, reciprocating frequency and percentage of aluminum has been studied. It is observed that the wear and coefficient of friction is influenced by the parameters. The tendency of wear goes on decreasing with the increase of normal load and it is minimum for a composite having 10%aluminum at a normal load of 0.7Kg and then goes on increasing at higher loads for all types of composite due to the adhesive nature of the composite. The coefficient of friction goes on decreasing with increasing normal loads due to the formation of thin film as an effect of heat generation with normal load.

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