Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2015 Aug;7(3):261-5.
doi: 10.1111/os.12194.

Effects of Cemented Hip Stem Pre-heating on Stem Push-out Strength

Vajara Wilairatana  1 , Chatchawan Pirot  2 , Noppachart Limpaphayom  1
Affiliations

Effects of Cemented Hip Stem Pre-heating on Stem Push-out Strength

Vajara Wilairatana et al. Orthop Surg. 2015 Aug.

Abstract

Objective: To determine the effect on ultimate push-out load and cement-stem surface shear strength of thermally manipulating the cobalt-chromium-molybdenum (CoCrMo) alloy stems of bone cement-stem constructs.

Methods: Satin-finished CoCrMo alloy stems were allocated to the following three groups with the predetermined temperatures: T24, ambient (24 °C); T37, body (37 °C); and T44, pre-heated stem (>44 °C). They were then inserted into hand-mixed high viscosity bone cement. Ultimate push-out load to failure was assessed with a servo hydraulic testing machine and the surface shear strength calculated. Data were compared among groups using the Kruskal-Wallis with Dunn's test. A P value of less than 0.05 was considered statistically significant.

Results: According to Kruskal-Wallis analysis, ultimate push-out load and surface shear strength differed significantly between the groups (P = 0.001). The T37 and T44 groups had higher ultimate push-out loads and surface shear strengths than the T24 group (P = 0.04 and 0.001, respectively). However, there was no statistically significant difference in these two variables between the T37 and T44 groups (P = 0.08).

Conclusions: Pre-heating CoCrMo alloy stems enhance the ultimate push-out load and surface shear strength in vitro. The suggested temperature is 37 °C. This technique is recommended for hip arthroplasty procedures.

Keywords: Cobalt-Chromium-Molybdenum alloy; Hip arthroplasty; Pre-heated femoral stem; Push-out test; Surface shear strength.

PubMed Disclaimer

Figures

Figure 1
Figure 1
Diagrammatic representation of the experimental set up of Cement‐Cobalt‐chromium‐molybdenum alloy stem construct in a temperature controlled (37 °C) thermocycling unit.
Figure 2
Figure 2
Ultimate push‐out load of CoCrMo alloy stems according to temperature.
Figure 3
Figure 3
Shear strength of CoCrMo alloy stems according to temperature.
See this image and copyright information in PMC

References

    1. Bektaser B, Solak S, Oguz T, Ocguder A, Akkurt MO. Total hip arthroplasty in patients with osteoarthritis secondary to developmental dysplasia of the hip: results after a mean of eight‐year follow‐up. Acta Orthop Traumatol Turc, 2007, 41: 108–112. - PubMed
    1. Bilsel N, Gokce A, Kesmezacar H, Mumcuoglu E, Ozdogan H. Long‐term results of total hip arthroplasty in patients with juvenile rheumatoid arthritis. Acta Orthop Traumatol Turc, 2008, 42: 119–124. - PubMed
    1. MacDowell AD, Howie DW. Fixation by Methyl Methacrylate In: Callaghan JJ, Rosenberg AG, Rubash HE, eds. The adult hip, Vol. 1, 2nd edn Philadelphia: Lippincott Williams & Wilkins, 2007; 184–194.
    1. Karthik K, Natarajan M. Unstable trochanteric fractures in elderly osteoporotic patients: role of primary hemiarthroplasty. Orthop Surg, 2012, 4: 89–93. - PMC - PubMed
    1. 11th Annual report 2014: National Joint Registry for England, Wales and Northern Ireland: National Joint Registry; [May 25, 2015]. Available from: http://www.njrcentre.org.uk/njrcentre/Reports, PublicationsandMinutes/Annualreports/tabid/86/Default.aspx.

LinkOut - more resources