This publication is not intended for distribution in the ... · stability due to one of the industry’s highest coefficients of friction of 1.2.10-12 Implant micromotion exceeding

This publication is not intended for distribution in the USA.

PRODUCT RATIONALE

Introduction 2

Proven Clinical Heritage of POROCOAT® 4

Built on the foundations of POROCOAT 5

Super Textured Asperity Topography (STAT) 6

High Coefficient of Friction 7

Gradient, High Volume Porosity 8

Optimal Pore Size 9

Manufacturing Process 10

Clinical Applications 12

GRIPTION Product Rationale DePuy Synthes 1

CONTENTS

GRIPTION exhibits a superior ‘scratch fit’ leading to increased primary stability due to one of the industry’s highest

coefficients of friction.10-12

Introduced in 1977, POROCOAT porous coating has more than 30 years of

clinical experience.1-9 In 2009 GRIPTION porous coating was introduced

to build on the foundation of the POROCOAT porous coating.

GRIPTION® porous coating is an evolutionary development in implant fixation technology designed for patients with an additional need of initial stability or a diminished implant contact area with the host bone.

DePuy Synthes Joint Reconstruction GRIPTION Product Rationale2

GRIPTION has an average pore size of 300 microns13,23 which lies within

the optimal range for tissue in growth into the structure and enables

vascularisation.14,16

GRIPTION exhibits a proprietary gradient porosity which is engineered with a clinically advantageous 80-percent surface volume porosity designed

to facilitate bone in-growth13,14 and a favorable mechanical loading

environment for bone formation.15

GRIPTION porous coating’s advanced structure is called ‘Super‑Textured Asperity Topography’ (STAT) and is a random array of

sintered, irregularly shaped, commercially pure titanium (CPT) particles forming a three‑dimensional network of interconnecting pores.


PROVEN CLINICAL HERITAGE

POROCOAT Porous Coating is a small-beaded, metal surface coating that sits proud on the surface of the implant and is designed for long-term cementless fixation.

Introduced in 1977, POROCOAT porous coating has more than 30 years of clinical experience1-9 and surgeons continue to trust the three-dimensional sintered bead coating structure. POROCOAT is supported by many peer reviewed published clinical papers reporting excellent results which is a testament to this well established technology.1-9 Peer-reviewed surgeon series of acetabular cups with POROCOAT porous coating show excellent survivorship rates.1,2,4 100% of DURALOC® acetabular implants had bone ingrowth into the porous-coated surface, with 0% aseptic loosening at 16 years,1 100% survivorship at 10 years of the DURALOC 300 cup2 and 96.1% survivorship at 8 years with the PINNACLE cup.4 These results are supported by multiple National Joint Registry results reporting 10-year survivorship rates of DURALOC at 94% survivorship in the Norwegian17 registry. The Australian18 Joint Registry, 2013 reported the DURALOC cup to have a 1.4% and 4.3% 10 year cumulative incidence of revision for loosening and lysis for crosslinked and non-crosslinked polyethylene respectively. This performance is also documented with the CORAIL PINNACLE construct results in the UK registry with 97.38% survivorship at 8 and 9 years for metal on polyethylene bearings.19 POROCOAT Porous Coating is found on a range of contemporary DePuy Synthes Joint Reconstruction products.

POROCOAT is made by sintering (high temperature bonding) a random array of spherical beads of titanium or cobalt chrome to an implant. The sintered beads form a three-dimensional network of interconnecting pores exhibiting optimal morphological properties for bone in-growth. POROCOAT’s high coefficient of friction of 0.810 provides a roughness that enables very good initial stability and facilitates the ‘scratch fit’ of the implant. It is engineered to provide a high and clinically advantageous ~80-percent volume porosity at the surface22 an average pore size of 250 microns,22 which is documented in a laboratory studies16 to be within the beneficial size range for good bone in-growth.

The three-dimensional, gradient structure of POROCOAT Porous Coating is designed to provide a favourable mechanical loading environment for bone formation.15 POROCOAT Porous Coating is manufactured with a coating tensile strength >23 Mpa25 to minimise coating delamination. The coating process has an average thickness of 0.762 (± 0.254 mm).25 This tolerance variance is intentional because it adds to the overall roughness of the coating. Research21 has demonstrated that virtually all bone growth onto and into an implant is at the outermost surface (only about 1-1.5mm deep into the pore structure), which reinforces the design characteristics of a sintered bead coating.


BUILT ON THE FOUNDATIONS OF POROCOAT

Characteristic POROCOAT10,22,25 GRIPTION10,13,23,24

Pore Size (Gradient Pore Size) ~250 microns (average) ~300 microns (average)

Volume Porosity ~80% (surface), 45% (average)

~80% (surface), 63% (average)

Thickness 0.762 (average) 0.889 (average)

Coating Tensile Strength >23 Mpa* >32 Mpa*

Coefficient of Friction 0.8 1.2

GRIPTION Porous Coating builds on the characteristics of POROCOAT and hence emulates some of its proven properties:

• GRIPTION has a pore size of 300 microns13,23 versus 250 microns for POROCOAT.22 Both POROCOAT and GRIPTION are documented in laboratory studies14,16 to be within the beneficial size range for good bone in-growth and vascular reconstitution.

• GRIPTION features a favourable three-dimensional, gradient structure, which is designed to provide a favorable mechanical loading environment for bone reconstitution15 The microtexture additionally enables greater cell adhesion and proliferation due to its morphology.14

• GRIPTION’s manufacturing principles and mechanical attributes are virtually identical to POROCOAT and therefore replicate many mechanical properties such as the resistance to delamination with a coating tensile strength >32 Mpa.24

• The GRIPTION Porous Coating is applied by first preparing the surface of the cup to accept a coat of the same spherical titanium beads as used for POROCOAT Porous Coating. Once these spherical beads are applied to the surface, multiple coats of irregularly shaped particles of titanium are applied directly over the top. The result is a high porosity, high friction GRIPTION surface.10,13,23

• GRIPTION exhibits a high co-efficient of friction for initial ‘scratch fit’ designed to increased primary stability based on one of the industry’s highest coefficients of friction at 1.2.10-12

• GRIPTION is engineered to feature a clinically advantageous gradient and very high volume porosity (80-percent at the surface).13

Comparison of the physical characteristics of POROCOAT and GRIPTION porous coatings

* Actual values associated with failure of the coating were not obtained. The highest strength result obtained with no coating failure is indicated, as cohesive failure occurred between the outer surface of the porous coating and the testing medium in all cases.


SUPER TEXTURED ASPERITY TOPOGRAPHYGRIPTION incorporates a unique Super-Textured Asperity Topography (STAT). STAT is a random array of irregularly shaped, commercially pure titanium (CP Ti) sintered particles forming a three-dimensional network of interconnecting pores. STAT is comprised of two differentiated structures; a macrotexture and a microtexture.

The microtexture comprises a series of peaks and troughs on the irregularly shaped titanium particles. This microtexture may improve the osteoblasts’ ability to stick to the surface, increasing adhesion strength and enabling cell proliferation on the coating surface.14


The unique Super-Textured Asperity Topography (STAT) of GRIPTION Porous Coating features initial ‘scratch fit’ stability due to one of the industry’s highest coefficients of friction of 1.2.10-12

Implant micromotion exceeding 150 microns results in fibrous attachment and poor bone formation onto and around an implanted device.20 Bearing this in mind, a superior coefficient of friction and therefore a better initial ‘scratch-fit’ stability may be crucial with regards to long-term fixation for a cementless implant. This may be especially important with regard to cases with a smaller host bone contact area (this may include revision or unusual primary cases), where the coefficient of friction may be an important factor for initial stability and long-term fixation of the implant.

Definition of Coefficient of Friction

The Coefficient of Friction is defined by the ratio of the force that maintains contact between an object and a surface and the frictional force that resists the motion of the object.

→ A Coefficient of Friction of 1.2 (GRIPTION Porous Coating) implicates that for each 1 kilogram of weight applied downward, it needs 1.2 kilograms of force to dislodge it.

HIGH COEFFICIENT OF FRICTION

Coefficient of Friction

GRIPTION10 TRITANIUM12 TRABECULAR METAL11

1.2

1.0 1.0


A property that is proprietary to DePuy Synthes porous coatings is its gradient porosity13 (see chart right).

GRIPTION like POROCOAT was designed with a gradient porosity.13 The intent of this gradient porosity is to assist with load sharing. The gradient coating design gives rise to highest density of metal at the substrate or surface of the cup and the lowest density of metal at the outer surface of the coating.13 This provides a smooth transition in porosity and metal density as bone grows through the coating from bone to substrate. The outermost surface of the coating being more porous results in more open space for vascurlarisation and good bone in growth. This gives a strong bone-to-implant interface, and might aid in stress shielding with the transition to lower porosity providing a favorable mechanical loading environment for bone formation.15,26 The outermost pores are typically filled with scraped bleeding bone upon impaction of the component.

GRIPTION is engineered to maintain a very high and clinically advantageous 80-percent volume porosity13 at the surface for good bone in-growth.14 This 80-percent volume porosity is equal to or better when compared to the volume porosity of other advanced coating surfaces in the market.11-13

Definition of Volume Porosity

Porosity is a measure of the void spaces in a material and is a fraction of the volume of voids over the total volume, expressed as a percentage between 0–100%.

→ A surface volume porosity of 80%13 (GRIPTION Porous Coating) indicates, that 80% of the area is void space at the bone implant interface.

GRADIENT, HIGH VOLUME POROSITY

Gradient Volume Porosity13

The volume of porosity increases as the distance from the cup surfaces increases.

Surface Volume Porosity

GRIPTION13 TRITANIUM12 TRABECULAR METAL11

~80%

~72%

<80%

100

90

80

70

60

50

40

30

20

10

0

Vol

ume

Poro

sity

(%)

Distance from the substrate (µm)0 250 500 750 1000


OPTIMAL PORE SIZE

GRIPTION has an average pore size of 300 microns,13,23 which is documented in laboratory studies to be within the beneficial size range of 50-400 microns for good bone in-growth and vascular reconstitution.16

Pores below 50 microns may hinder uniform maturation of tissue: in larger pores, 400 microns and above, in-growth may be slow, inconsistent and tends to be fibrous.16

Definition of Pore Size

Pore size is a measure of the average diameter of a material’s pores (this usually includes a definition of the range of pore sizes).

→ GRIPTION Porous Coating has an average pore size of 300 microns.13,23

Opt

imal

Por

e Si

ze

50

-40

0 µ

m

Optimal Pore Size

GRIPTION13,23 TRITANIUM12 TRABECULAR METAL11

~300 µm

~546 µm ~550 µm


The manufacturing process for PINNACLE cups with GRIPTION Porous Coating is very similar to the manufacturing process for coating with POROCOAT.

Raw ForgingThe PINNACLE Shell forging is essentially a “blank” that can be made into almost any PINNACLE cup design including the 100, 300, Sector, Multihole or Bantam series.

Outer Diameter MachinedThe forging is machined at this stage to include the apical hole and any screw holes.

GRIPTION Porous Coating AppliedThe surface of the cup is prepared to accept a coat of the same spherical titanium beads as used for POROCOAT Porous Coating. Once these spherical beads are applied to the surface, multiple coats of irregularly shaped particles of titanium are applied directly over the top. The result is a high porosity, high friction GRIPTION surface.10,13,23 (Were this a cup with POROCOAT Porous Coating, only spherical beads would be applied.)

Inner Diameter MachinedFollowing the sintering process (sintering is the process of high temperature bonding of the beads to the implant creating a strong metallurgical bond between the implant and the fused beads), the PINNACLE shell’s inner diameter is machined to accept the liners.26

Finished Pinnacle CupPINNACLE Cups with GRIPTION Coating are checked against specification and are cleaned, boxed and sterilised.


MANUFACTURING PROCESS


There are three groups of patients that may stand to gain the most from GRIPTION’s high coefficient of friction, high gradient volume porosity and optimal pore size:

• Atypical Primary Patients (in the case of a diminished contact area of the implant with the host bone) This may include DDH, rheumatoid protrusio, prior fusion, severe natural anteversion or retroversion deformity, or tumour.

• Traditional Revision Patients This may include revisions of failed cemented cups, minor to moderate protrusio, migrated shell, osteolytic defects and false acetabulum, where a loss of host bone may compromise primary fixation.

• Primary Patients with an Additional Need for Initial Stability Any other primary patients where surgeons feel an improved initial scratch fit is of benefit.

12 DePuy Synthes GRIPTION Product Rationale

CLINICAL APPLICATIONS

References

1. Kim Y-H, Kim J-S and Park J-W. Is Hydroxyapatite Coating Necessary to Improve Survivorship of Porous-Coated Titanium Femoral Stem?J Arthroplasty. 2012;27:559-563.

2. Grobler GP et al. Ten-year results of a press-fit, porous-coated acetabular component. J Bone Joint Surg Br 2005;87:786-9.

3. Kindsfater K, Barrett WP, Dowd JE, Southworth CB and Cassell MJ. “99.9% Midterm Survival of the Pinnacle Multi- Liner Acetabular Cup in a Prospective Multi-Center Study.” Poster Presentation #P077, AAOS, San Diego, CA. February 14-18, 2007.

4. DePuy Orthopaedics, Inc. Internal Study Update. PINNACLE Multi-Liner Acetabular Cup in a Prospective Multi-Center Study. May 2011.

5. Engh CA, et al. “Porous-Coated Total Hip Replacement.” Clin Orthop Rel Res. 1994;298:89-96

6. Onodera S, et al. Cementless total hip arthroplasty using the modular S-ROM prosthesis combined with corrective proximal femoral osteotomy. J Arthroplasty. 2006;21(5):664-9.

7. Cameron HU, Keppler L and McTighe T. The Role of Modularity in Primary Total Hip Arthroplasty. J Arthroplasty. 2006;21 Suppl 1:89-92.

8. Chiu KY, et al. Cementless total hip arthroplasty in young Chinese patients: a comparison of 2 different prostheses. J Arthroplasty. 2001;16(7):863-70.

9. Burt CF, Garvin KL and Erik TA. Femoral Component Inserted Without Cement In Total Hip Arthroplasty, A Study Of The Tri-Lock Component With an Average Ten-Year Duration of Follow-Up. J Bone Joint Surg Am 1998;80-A:952-960

10. DePuy Internal Test Report: WR070146; 2007.

11. Published literature: No.97-7864-001-00 7.5ML, Zimmer Inc, 2005 and Zimmer Inc, Trabecular Metal Technology. Website accessed February 17, 2014 at URL http://www.zimmer.com/en-US/hcp/hip/our-science/tm-technology.jspx

12. Published data of the Stryker Orthopaedics Test Report RD-07-077. Website accessed January 10, 2014 at URL http://www.stryker.com/en-us/products/ Orthopaedics/HipReplacement/PrimaryAcetabular/ TritaniumAcetabularShell/index .htm.

13. DePuy Internal Test Report: WR070125; 2007.

14. Karageorgiou V, et al. Porosity of 3D biomaterial scaffolds and osteogenesis. Biomaterials 2005;26:5474-91

15. Simmons, et al. Differences in osseointegration rate due to implant surface geometry can be explained by local tissue strains. J Orthop Res 2001;19:187-194

16. Bobyn JD, Pilliar RM, Cameron HU, Weatherly GC. The optimum pore size for the fixation of porous surfaced metal implants by the ingrowth of bone. Clin Orthop Rel. Res. 1980;150:263-270.

17. Furnes O, et al. Prospective studies of hip and knee prostheses - the Norwegian Arthroplasty Register 1987-2004. Scientific Exhibit presented at 72nd Annual Meeting of the American Academy of Orthopaedic Surgeons, Washington, DC, USA. Feb 2005.

18. Australian Orthopaedic Association National Joint Replacement Registry. Annual Report. Adelaide: AOA; 2013. Available from URL: https://aoanjrr.dmac.adelaide.edu.au/annual-reports-2013. Page 76.

19. National Joint Registry for England, Wales and Northern Ireland 10th Annual Report 2013 Table 3.12.

20. Jasty M, et al. In vivo skeletal responses to porous-surfaced implants subjected to small induced motions. J Bone Joint Surg Am. 1997;79(5):707-14.

21. Ayers RA, et al. Quantification of bone ingrowth into porous block hydroxyapatite in humans. J Biomed Mater Res.1999: 47(1):54-59.

22. DePuy Internal Test Report: Master File 60.

23. DePuy Synthes Data on File, Master File 1478.

24. DePuy Synthes Data on File, WR070087,070065.

25. DePuy Synthes Data on File, 510(k) 934457.

26. DePuy Synthes Data on File: Strength of GRIPTION Porous Coating.

©DePuy Synthes Joint Reconstruction, a division of Johnson & Johnson Medical Limited. 2014. All rights reserved.

DePuy Synthes Joint Reconstruction is a trading division of Johnson & Johnson Medical LimitedPO BOX 1988, Simpson Parkway, Livingston, West Lothian, EH54 0AB, United KingdomIncorporated and registered in Scotland under company number SC132162.

depuysynthes.com

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DePuy (Ireland)LoughbegRingaskiddyCo. CorkIrelandTel: +353 21 4914 000 Fax: +353 21 4914 199

DePuy Orthopaedics, Inc. 700 Orthopaedic DriveWarsaw, IN 46582USATel: +1 (800) 366 8143Fax: +1 (574) 267 7196

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CA#DPEM/ORT/0513/0020 Issued: 10/14

Documents

This publication is not intended for distribution in the ... · stability due to one of the industry’s highest coefficients of friction of 1.2.10-12 Implant micromotion exceeding