Open Access

An in vitro study comparing limited to full cementation of polyethylene glenoid components

  • R. Andrew Glennie1,
  • Joshua W. Giles2,
  • James A. Johnson2,
  • George S. Athwal2 and
  • Kenneth J. Faber2Email author
Journal of Orthopaedic Surgery and Research201510:142

https://doi.org/10.1186/s13018-015-0268-7

Received: 6 April 2015

Accepted: 28 July 2015

Published: 17 September 2015

Abstract

Background

Glenoid component survival is critical to good long-term outcomes in total shoulder arthroplasty. Optimizing the fixation environment is paramount. The purpose of this study was to compare two glenoid cementing techniques for fixation in total shoulder arthroplasty.

Methods

Sixteen cadaveric specimens were randomized to receive peg-only cementation (CPEG) or full back-side cementation (CBACK). Physiological cyclic loading was performed and implant displacement was recorded using an optical tracking system. The cement mantle was examined with micro-computed tomography before and after cyclic loading.

Results

Significantly greater implant displacement away from the inferior portion of the glenoid was observed in the peg cementation group when compared to the fully cemented group during the physiological loading. The displacement was greatest at the beginning of the loading protocol and persisted at a diminished rate during the remainder of the loading protocol. Micro-CT scanning demonstrated that the cement mantle remained intact in both groups and that three specimens in the CBACK group demonstrated microfracturing in one area only.

Discussion

Displacement of the CPEG implants away from the inferior subchondral bone may represent a suboptimal condition for long-term implant survival. Cement around the back of the implant is suggested to improve initial stability of all polyethylene glenoid implants.

Clinical relevance

Full cementation provides greater implant stability when compared to limited cementation techniques for insertion of glenoid implants. Loading characteristics are more favorable when cement is placed along the entire back of the implant contacting the subchondral bone.

Introduction

Glenoid component loosening is a common cause of failed total shoulder arthroplasty (TSA) [1, 2]. Multiple studies have identified factors associated with glenoid component failure including glenohumeral mismatch, glenohumeral instability, excessive glenoid reaming at the time of surgery, cementing techniques, malalignment of the glenoid component, and osteopenic host bone [1, 3].

Although different methods of glenoid fixation are available, clinical and biomechanical studies would suggest that all polyethylene-cemented implants may have better initial in vitro stability and superior mid- and long-term clinical survivorship when compared to metal-backed implants [47]. Polyethylene glenoid prostheses can be broadly categorized as either “keeled” or “pegged.” Currently, the cement mantle required for adequate initial fixation and durable long-term survivorship of polyethylene prostheses is not well established [812].

Little is known about the effect of various glenoid cementation techniques in total shoulder arthroplasty. Several recent publications examining the effect of pressurization found improved cement interdigitation within cancellous bone that theoretically creates a stronger initial bond to the host bone that may enhance implant stability, minimize radiolucent lines, and increase implant survivorship [1315]. In addition, Neer suggested that building up cement along the back of the implant lead to poorer implant survival since there was higher potential edge loading and therefore more opportunity for cement fracturing and third body debris in the joint potentially starting the cascade of osteolysis [16]. Others have observed higher implant failure rates when the cancellous bone is exposed for cementation and suggested that preservation of the subchondral plate is critical for implant survival [17]. When the subchondral plate is preserved, there is little opportunity for cement interdigitation with cancellous bone. The purpose of this study was to compare the micro-computed tomography (micro-CT) findings and biomechanical characteristics of two cementation techniques employed during subchondral plate-sparing glenoid preparation. The null hypothesis is that both cementation techniques will demonstrate no significant difference in cement mantle changes on micro-CT and similar biomechanical properties regardless of cementation technique.

Materials and methods

Specimen preparation

Sixteen unmatched cadaveric human shoulder specimens were tested (ages 42–75). Each specimen was imaged with radiographs to ensure there were no osseous abnormalities that would prevent component implantation. Seven scapulae were randomized to receive a traditional fully cemented technique with cement around the pegs and the back-side of the implant (CBACK) and nine were randomized to a limited cementing technique only around the implanted pegs (CPEG). Randomization was carried out with a random number generator.

After each specimen was thawed and stripped of soft tissues, the glenoid was prepared to accept a 46-mm pegged prosthesis using the surgical technique provided by the implant manufacturer (Anatomical™, Zimmer, Warsaw, IN). Reaming to create a conforming surface for the implants was performed in a manner that preserved the deep cortical plate in all specimens. All scapulae included in the study were size-matched to accommodate a 46-mm implant. The humeral head was simulated using an instrumented steel ball that corresponded to the manufacturer’s recommended radius of curvature mismatch. Third-generation cementation technique was used as described by Reiss and Nyfeller [18, 19]. For the CBACK specimens, cement was injected (Simplex, Stryker, NJ) into the glenoid peg holes and onto the subchondral glenoid bone. Additional cement was intentionally placed on the convex back surface of the component. The cement was then pressurized and the implant inserted. The limited cementation technique (CPEG) injected and pressurized cement into the glenoid peg holes with a syringe. No cement was applied to the convex back surface of the implant or to the glenoid face. Any excess cement that leaked from the peg holes was removed from the back of the implant. In both techniques, the excess cement was removed beyond the margins of the polyethylene and the component was pressed against the glenoid face with an impaction device until the cement was fully cured.

Mechanical testing of micro-stability

Glenoid component deformation and differential movement between the component and the adjacent bone was measured using an optical tracking system (OptoTrak Certus, NDI, Waterloo, ON). Two trackers were necessary: a reference tracker was placed on the glenoid bone remote from the implant and the second tracker was placed on the inferior edge of the polyethylene implant. A reference marker was placed on the bone adjacent to the bone-implant interface in order to compensate for all movement of the underlying bone that would otherwise appear as component displacement when recorded by the implant marker (Fig. 1). The optical tracking system was calibrated and confirmed to have a resolution of 0.01 mm and an accuracy of 0.1 mm prior to initiation of testing.
Fig. 1

The optical tracker demonstrated on the inferior aspect of the glenoid polyethylene

A sinusoidal cyclic loading protocol was used to continuously load the construct with a 30 degree force vector in the superior direction for a total of 10,000 repetitions at 1250 N. This testing regimen was chosen to simulate 5 high load activities (e.g., rising from a chair, walking with a walker, turning a locked steering wheel, etc.) per day over a 6-year period [20]. Similar loading regimens have been suggested previously [21]. The force vector was achieved using a pneumatic loading apparatus and applied to the glenoid via a custom steel ball with a radius of curvature equivalent to the implant manufacturer’s recommended corresponding humeral head implant (Fig. 2).
Fig. 2

The loading apparatus demonstrates a 30° loading vector with two optical trackers. One optical tracker is attached to the polyethylene and one is attached to the bone as a reference. The scapula is potted within the cement box. There is masking tape over the humeral ball to reduce potential reflection to the camera (not shown)

Loading and optical tracking data were continuously recorded using LabVIEW software (National Instruments, Austin TX). Mean data at the 50th, 100th, 200th, 500th, 1000th, 5000th, and 10,000th cycle for each group was compared using analysis of variance (ANOVA) in SPSS (IBM, Armonk, NY).

CT-based radiological assessments

After specimen preparation and before loading, baseline micro-computed tomography (micro-CT) scans were obtained to evaluate the initial incorporation of cement into the glenoid bone surface and in the peg holes. The glenoid samples were imaged using the Locus Ultra micro-CT scanner (General Electric, Fairfield, CT). The scanner has an in-plane field of view of 140 mm in diameter and an axial field of view of 96 mm in length. The samples were imaged with an x-ray source voltage of 120 kV and a current of 20 mA. In a scan time of less than a minute, 1000 views were acquired. The data were reconstructed into a three-dimensional (3-D) image volume with an isotropic voxel size of 154 μm. After completion of the complete loading protocol, the micro-CT scanning was repeated. General Electric Health Care MicroView™ (General Electric, Fairfield, CT) software was used to quantitatively evaluate three-dimensional images of the construct (Fig. 3).
Fig. 3

Specimen 8 demonstrates slight change at the anterior portion of the cement mantle interface specifically comparing pre-loading and post-loading CT images

Micro-CT images were evaluated in a random and blinded order and data was recorded using a modified scoring system that was based on the scoring system previously described by Walch [22]. An example of each technique, both CBACK and CPEG, can be found in Fig. 4. Average thickness of the cement mantle was recorded for the CBACK components. Each component was divided into eight different zones that corresponded to positions on the medial surface of the glenoid prosthesis (Fig. 5). A score of 0 was assigned if no radiolucent lines were present within a zone and a score of 1 was assigned if radiolucent lines were present within the zone. A radiolucent line was defined as a visible radiolucency ≥1 mm comparing identical CT images pre- and post-loading. The eight zones of the pre- and post-loading images were compared using chi-squared analysis to determine whether any significant radiolucent lines or cement fractures had developed. All eight zones were carefully scrutinized in each specimen for any evidence of microfracture.
Fig. 4

Examples of CPEG micro-CT scan on the left image and CBACK on the image to the right. The CPEG implant shows no cement along the back of the component whereas the CBACK component shows cement extruding along the undersurface and side of the implant

Fig. 5

Glenoids were divided into eight zones of interest. The superior peg lies in between zone 2 and 3. The central peg lies in between zones 4 and 5 and the inferior pegs lie in zones 6 and 7

Results

Micro-stability testing

One of the specimens from the CBACK group was excluded due to inadvertent camera movement near the beginning of the loading cycle. Therefore, the camera could not visualize the tracker and the data was not recorded.

There was a significant difference in the displacement of the polyethylene implant when comparing CBACK and CPEG cementation techniques dynamically (p = 0.03). Physiological loading displaced the implant away from the inferior portion of the glenoid (Fig. 6). The initial mean displacement of the CPEG components at 50 cycles was 0.156 ± 0.038 mm whereas mean displacement of CBACK components was 0.055 ± 0.010 mm (p = 0.017). At 10,000 cycles, the mean displacement of the CPEG components increased to 0.255 ± 0.039 mm (p = 0.001). This data is summarized in Table 1.
Fig. 6

Representation of the glenoid being loaded in a superior direction and demonstrating lift-off as detected by the optical trackers at the inferior portion of the subchondral bone

Table 1

Mean displacement measurements at different cyclic loading points for both CPEG and CBACK implantation techniques

 

CPEG

CBACK

50

0.156 ± 0.114

0.055 ± 0.026

100

0.203 ± 0.094

0.050 ± 0.029

200

0.211 ± 0.097

0.048 ± 0.033

500

0.220 ± 0.097

0.054 ± 0.029

1000

0.233 ± 0.106

0.051 ± 0.035

5000

0.246 ± 0.108

0.052 ± 0.035

10000

0.255 ± 0.118

0.054 ± 0.039

The CPEG implants had significant and progressive displacement throughout the cyclic testing protocol (Fig. 7). Using a Bonferroni correction for multiple comparisons, the mean difference (0.017 mm) was significant between 100 and 500 cycles (p = 0.019), as well as the difference (0.03 mm) between 100 and 1000 cycles (p = 0.029). In contrast, there was no significant difference in displacement of the CBACK components throughout the protocol (p = 0.45). The measured displacement occurred between the optical trackers fixed to the inferior portion of the glenoid component and the host glenoid bone.
Fig. 7

Graph demonstrates initial increase in displacement in CPEG implants with increasing cycles. This gradual increase in displacement plateaus as the number of cycles increase. There is no appreciable difference in initial of final displacement with CBACK components

Micro-CT assessments

In the 16 scapular specimens, there was no significant change in appearance of the polyethylene/cement/glenoid bone interface when comparing the eight zones of interest (p = 0.14). Cement mantle thickness ranged from 1.2 to 2.0 mm for all CBACK specimens. Cement mantle fracture was not observed in any specimen and cement mantle defects observed after initial cementation did not progress or change after the loading protocol. Three CBACK specimens had 1-mm radiolucent lines at sites 3, 5, and 8 (anterior position) of the subchondral surface after loading. Specimen #3 demonstrated radiolucent lines in zones 3 and 8. No significant changes were observed at the superior, inferior, or posterior positions. There were no changes to the bone under the cement mantle indicative of bony compression or fracture. There was no appreciable change in polyethylene shape when comparing pre and post micro-CT scans (Table 2).
Table 2

Change in appearance of radiolucent lines for each zone

 

Zone

Specimen #

1

2

3

4

5

6

7

8

1 (CPEG)

0

0

0

0

0

0

0

0

2 (CPEG)

0

0

0

0

0

0

0

0

3 (CBACK)

0

0

1

0

0

0

0

1

4 (CBACK)

0

0

0

0

1

0

0

0

5(CPEG)

0

0

0

0

0

0

0

0

6 (CPEG)

0

0

0

0

0

0

0

0

7 (CPEG)

0

0

0

0

0

0

0

0

8 (CBACK)

0

0

0

0

0

0

0

1

9 (CPEG)

0

0

0

0

0

0

0

0

10 (CPEG)

0

0

0

0

0

0

0

0

11 (CBACK)

0

0

0

0

0

0

0

0

12 (CPEG)

0

0

0

0

0

0

0

0

13 (CPEG)

0

0

0

0

0

0

0

0

14 (CBACK)

0

0

0

0

0

0

0

0

15 (CBACK)

0

0

0

0

0

0

0

0

16 (CBACK)

0

0

0

0

0

0

0

1

1 indicates the presence of new radiolucent line and 0 indicates no change

Discussion

Establishing a cyclic loading protocol and method for determining displacement of polyethylene components in total shoulder arthroplasty can be valuable when evaluating new designs [2325]. We developed a testing model that is capable of assessing displacement of components dynamically during cyclic loading. Micro-CT scans were useful to confirm that there was no gross abnormality of the cement mantle prior to cyclic testing and at the end of the protocol. The fact that there were no cement mantle fractures was surprising to us, as we theorized that the thin cement mantle would likely fracture during cyclic loading.

The optical tracking during cyclic loading produced several interesting findings related to glenoid component displacement. Implants inserted with the CPEG technique had an initial “setting in” of the component during the first 1000 cycles and thereafter the rate of gradual lift-off diminished but did not cease. This indicates that there was ongoing displacement of the implant relative to the glenoid bone that could represent an early mode of failure with this technique.

Radiostereometric analysis (RSA) has been used to measure in vivo implant displacement following total hip and knee arthroplasty [26]. Two displacement patterns emerge; either the implant achieves solid initial fixation after a brief period of “setting in” or the implant continues to displace. The latter scenario is predictive of catastrophic failure in polyethylene tibial components [27, 28]. A similar conclusion may possibly be drawn here where significant initial movement of the CPEG implant may be predictive of accelerated failure when compared with the CBACK technique that demonstrated no movement.

The observation of implant displacement away from the glenoid bone was not associated with failure and overt loosening in our study as confirmed with the micro-CT data. We are concerned that the initial implant displacement persisted albeit at a diminished rate during extended cyclical loading. It has been shown previously that any tensile force or distraction at a bone cement interface may impact upon long-term implant survival [29]. What we observed could represent a mode of failure whereby synovial fluid accesses and egresses from the space between the implant and host bone.

Many authors have stressed that the initial stability of the implant may be a major determinant for long-term survival [15, 9]. Our results indicated that implant displacement away from the glenoid bone was not observed with the CBACK cementing technique. This may indicate better fixation and potentially improved survivability. The presence of radiolucent lines however in 3 of the 7 CBACK specimens, although not statistically significant, is an interesting observation. Although the loading mechanical properties were not affected in vitro, over time, these radiolucent lines may generate particulate debris that can initiate the cascade leading to osteolysis.

Movement of the inferior portion of the polyethylene away from the glenoid subchondral bone as was observed with limited cementation or the CPEG group may be a suboptimal environment for long-term fixation due to the gradual worsening lift-off and possible fluid egress into the bone cement interface. Although the initial displacement trend decreases after the first 1000 cycles, the implant continues to move relative to the tracker on the bone and this trend may either continue slowly or lead to eventual failure. The initial and sustained stability observed with the CBACK components throughout the loading protocol was superior and warrants further in vivo investigation.

The major limitation of this work was using a loading protocol that represented 5 high load activities per day. This is the equivalent of 150 % body weight 5 times per day for 6 years. The loading protocol may underestimate the actual loads the implant is subjected to during normal day-to-day activities particularly if joint replacements are performed in a younger population. If we assumed double the number of high load activities then our protocol would only represent cyclic loads that the prosthesis is exposed to during a 3-year period. Concerns that specimen degradation may occur during testing precluded prolonging the cyclic loading portion of the testing protocol. Specimen preparation took roughly 12 h in total in addition to the loading protocol. Future study may need to focus on much higher numbers of cycles and perhaps even loading specimens to failure with cycling. An additional limitation with this study and future studies using cyclic loading will be the ongoing accuracy and the potential error of the cyclic loading data with respect to the optical tracking system.

Conclusion

Total shoulder arthroplasty is an important pain-relieving operation and we must continue to develop implants and optimize implantation techniques that enhance implant survivorship. The lift-off or displacement of the CPEG implants that was observed during the dynamic testing protocol is concerning and may be associated with glenoid loosening. Further in vitro and in vivo testing and analysis are required to determine the long-term survival of current cementing techniques.

Declarations

Acknowledgements

The authors would like to thank Joseph Umoh for all of his help in obtaining micro-CT scans of all of our specimens.

Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.

Authors’ Affiliations

(1)
Department of Orthopedics, Dalhousie University
(2)
Division of Orthopedics, Western University

References

  1. Matsen 3rd FA, Clinton J, Lynch J, Bertelsen A, Richardson ML. Glenoid component failure in total shoulder arthroplasty. J Bone Joint Surg Am. 2008;90(4):885–96. doi:10.2106/JBJS.G.01263.View ArticlePubMedGoogle Scholar
  2. Nagels J, Valstar ER, Stokdijk M, Rozing PM. Patterns of loosening of the glenoid component. J Bone Joint Surg. 2002;84(1):83–7.View ArticleGoogle Scholar
  3. Hopkins AR, Hansen UN, Amis AA, Knight L, Taylor M, Levy O, et al. Wear in the prosthetic shoulder: association with design parameters. J Biomech Eng. 2007;129(2):223–30. doi:10.1115/1.2486060.PubMedGoogle Scholar
  4. Rahme H, Mattsson P, Wikblad L, Nowak J, Larsson S. Stability of cemented in-line pegged glenoid compared with keeled glenoid components in total shoulder arthroplasty. J Bone Joint Surg Am. 2009;91(8):1965–72. doi:10.2106/JBJS.H.00938.View ArticlePubMedGoogle Scholar
  5. Nuttall D, Haines JF, Trail II. A study of the micromovement of pegged and keeled glenoid components compared using radiostereometric analysis. J Shoulder Elbow Surg. 2007;16(3 Suppl):S65–70. doi:10.1016/j.jse.2006.01.015.View ArticlePubMedGoogle Scholar
  6. Gartsman GM, Elkousy HA, Warnock KM, Edwards TB, O’Connor DP. Radiographic comparison of pegged and keeled glenoid components. J Shoulder Elbow Surg. 2005;14(3):252–7. doi:10.1016/j.jse.2004.09.006.View ArticlePubMedGoogle Scholar
  7. Edwards TB, Labriola JE, Stanley RJ, O’Connor DP, Elkousy HA, Gartsman GM. Radiographic comparison of pegged and keeled glenoid components using modern cementing techniques: a prospective randomized study. J Shoulder Elbow Surg. 2010;19(2):251–7. doi:10.1016/j.jse.2009.10.013.View ArticlePubMedGoogle Scholar
  8. Martens KA, Edwards SL, Omar IM, Saltzman MD. Heat generated with pegged or keeled glenoid components fixed with defined amounts of cement. Orthopedics. 2012;35(4):e469–73. doi:10.3928/01477447-20120327-14.View ArticlePubMedGoogle Scholar
  9. Nuttall D, Haines JF, Trail IA. The early migration of a partially cemented fluted pegged glenoid component using radiostereometric analysis. J Shoulder Elbow Surg. 2012;21(9):1191–6. doi:10.1016/j.jse.2011.07.028.View ArticlePubMedGoogle Scholar
  10. Wirth MA, Loredo R, Garcia G, Rockwood Jr CA, Southworth C, Iannotti JP. Total shoulder arthroplasty with an all-polyethylene pegged bone-ingrowth glenoid component: a clinical and radiographic outcome study. J Bone Joint Surg Am. 2012;94(3):260–7. doi:10.2106/JBJS.J.01400.View ArticlePubMedGoogle Scholar
  11. Gregory T, Hansen U, Taillieu F, Baring T, Brassart N, Mutchler C, et al. Glenoid loosening after total shoulder arthroplasty: an in vitro CT-scan study. J Orthop Res. 2009;27(12):1589–95. doi:10.1002/jor.20912.View ArticlePubMedGoogle Scholar
  12. Wallace AL, Phillips RL, MacDougal GA, Walsh WR, Sonnabend DH. Resurfacing of the glenoid in total shoulder arthroplasty. A comparison, at a mean of five years, of prostheses inserted with and without cement. J Bone Joint Surg Am. 1999;81(4):510–8.PubMedGoogle Scholar
  13. Gross RM, High R, Apker K, Haggstrom J, Fehringer JA, Stephan J. Vacuum assist glenoid fixation: does this technique lead to a more durable glenoid component? J Shoulder Elbow Surg. 2011;20(7):1050–60. doi:10.1016/j.jse.2011.04.007.View ArticlePubMedGoogle Scholar
  14. Choi T, Horodyski M, Struk AM, Sahajpal DT, Wright TW. Incidence of early radiolucent lines after glenoid component insertion for total shoulder arthroplasty: a radiographic study comparing pressurized and unpressurized cementing techniques. J Shoulder Elbow Surg. 2012. doi:10.1016/j.jse.2012.05.041.
  15. Raiss P, Sowa B, Bruckner T, Eck S, Woerz S, Rohr K, et al. Pressurisation leads to better cement penetration into the glenoid bone: a cadaveric study. J Bone Joint Surg. 2012;94(5):671–7. doi:10.1302/0301-620X.94B5.28831.View ArticleGoogle Scholar
  16. Neer 2nd CS, Kirby RM. Revision of humeral head and total shoulder arthroplasties. Clin Orthop Relat Res. 1982;170:189–95.PubMedGoogle Scholar
  17. Walch G, Young AA, Boileau P, Loew M, Gazielly D, Mole D. Patterns of loosening of polyethylene keeled glenoid components after shoulder arthroplasty for primary osteoarthritis: results of a multicenter study with more than five years of follow-up. J Bone Joint Surg Am. 2012;94(2):145–50. doi:10.2106/JBJS.J.00699.View ArticlePubMedGoogle Scholar
  18. Raiss P, Pape G, Kleinschmidt K, Jager S, Sowa B, Jakubowitz E, et al. Bone cement penetration pattern and primary stability testing in keeled and pegged glenoid components. J Shoulder Elbow Surg. 2011;20(5):723–31. doi:10.1016/j.jse.2010.09.006.View ArticlePubMedGoogle Scholar
  19. Nyffeler RW, Meyer D, Sheikh R, Koller BJ, Gerber C. The effect of cementing technique on structural fixation of pegged glenoid components in total shoulder arthroplasty. J Shoulder Elbow Surg. 2006;15(1):106–11. doi:10.1016/j.jse.2005.05.002.View ArticlePubMedGoogle Scholar
  20. Bergmann G, Graichen F, Bender A, Kaab M, Rohlmann A, Westerhoff P. In vivo glenohumeral contact forces—measurements in the first patient 7 months postoperatively. J Biomech. 2007;40(10):2139–49. doi:10.1016/j.jbiomech.2006.10.037.View ArticlePubMedGoogle Scholar
  21. Iannotti JP, Lappin KE, Klotz CL, Reber EW, Swope SW. Liftoff resistance of augmented glenoid components during cyclic fatigue loading in the posterior-superior direction. J Shoulder Elbow Surg. 2013;22(11):1530–6. doi:10.1016/j.jse.2013.01.018.View ArticlePubMedGoogle Scholar
  22. Walch G, Edwards TB, Boulahia A, Boileau P, Mole D, Adeleine P. The influence of glenohumeral prosthetic mismatch on glenoid radiolucent lines: results of a multicenter study. J Bone Joint Surg Am. 2002;84-A(12):2186–91.PubMedGoogle Scholar
  23. Kwon YW, Forman RE, Walker PS, Zuckerman JD. Analysis of reverse total shoulder joint forces and glenoid fixation. Bull NYU Hosp Jt Dis. 2010;68(4):273–80.PubMedGoogle Scholar
  24. Schamblin M, Gupta R, Yang BY, McGarry MH, McMaster WC, Lee TQ. In vitro quantitative assessment of total and bipolar shoulder arthroplasties: a biomechanical study using human cadaver shoulders. Clin Biomech. 2009;24(8):626–31. doi:10.1016/j.clinbiomech.2009.05.007.View ArticleGoogle Scholar
  25. Hopkins AR, Hansen UN, Amis AA, Taylor M, Emery RJ. Glenohumeral kinematics following total shoulder arthroplasty: a finite element investigation. J Orthop Res. 2007;25(1):108–15. doi:10.1002/jor.20290.View ArticlePubMedGoogle Scholar
  26. Nieuwenhuijse MJ, Valstar ER, Kaptein BL, Nelissen RG. The Exeter femoral stem continues to migrate during its first decade after implantation: 10–12 years of follow-up with radiostereometric Analysis (RSA). Acta Orthop. 2012;83(2):129–34. doi:10.3109/17453674.2012.672093.PubMed CentralView ArticlePubMedGoogle Scholar
  27. Pijls BG, Valstar ER, Nouta KA, Plevier JW, Fiocco M, Middeldorp S, et al. Early migration of tibial components is associated with late revision: a systematic review and meta-analysis of 21,000 knee arthroplasties. Acta Orthop. 2012;83(6):614–24. doi:10.3109/17453674.2012.747052.PubMed CentralView ArticlePubMedGoogle Scholar
  28. Vanlommel J, Luyckx JP, Labey L, Innocenti B, De Corte R, Bellemans J. Cementing the tibial component in total knee arthroplasty: which technique is the best? J Arthroplasty. 2011;26(3):492–6. doi:10.1016/j.arth.2010.01.107.View ArticlePubMedGoogle Scholar
  29. Karduna AR, Williams GR, Iannotti JP, Williams JL. Total shoulder arthroplasty biomechanics: a study of the forces and strains at the glenoid component. J Biomech Eng. 1998;120(1):92–9.View ArticlePubMedGoogle Scholar

Copyright

© Glennie et al. 2015

Advertisement