Facing metaphyseal bone stock defects: Mid- and longterm results of cones

Stephanie Kirschbaum; Carsten Perka; Clemens Gwinner

doi:10.1016/j.jor.2020.12.015

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23 (); 31-36

doi:

10.1016/j.jor.2020.12.015

Facing metaphyseal bone stock defects: Mid- and longterm results of cones

Stephanie Kirschbaum, Carsten Perka, Clemens Gwinner

Center for Musculoskeletal Surgery, Charité-University Medicine Berlin, Germany

∗Corresponding author: Stephanie Kirschbaum. stephanie.kirschbaum@charite.de

Received: 2020-11-1, Accepted: 2020-12-8, Published: 2020-12-23

Professor P K Surendran Memorial Education Foundation

Disclaimer:
This article was originally published by Reed Elsevier India Pvt. Ltd. and was migrated to Scientific Scholar after the change of Publisher.

1

1 Introduction

Revision total knee arthroplasty (TKA) is often accompanied by severe bone loss, due to infection, osteolysis, loosening of the primary implant or iatrogenic bone loss owing to implant removal.²^,¹³ As the number of revision knee arthroplasty is estimated to increase by 600% until 2030,¹⁵ it is important to further improve surgical solutions. Proper fixation and by that good long-term survival depends on the amount and type of bone loss and on the amount of bone that is left for fixation.^3,10 Therefore, the following 2 classifications are important, and each case should be analysed by applying both pre-OP and intra-OP.

1.1

1.1 Classification of bone stock defects

Optimal surgical strategy depends on the size and shape of the bone stock defect, which is described by the classification of the Anderson Orthopedic Research Institute (AORI).¹⁰ More specifically, an AORI defect grade I describes an isolated cystic lesion near the joint line, demonstrating intact metaphysis and cortical bone. An AORI defect type IIa shows half sided (medial or lateral) bony lesion of the metaphysis, while type grade IIb shows bilateral defect of femoral or tibial metaphysis. An AORI defect type III shows complete loss of metaphysis including insufficiency or tear of collateral or patella ligament (Fig. 1).

Classification of the Anderson Orthopedic Research Institute (AORI) described by Engh et al. 1998.10

1.2

1.2 Where and how to fixate a revision TKA?

According to the landmark paper of Morgan-Jones et al., fixation of revision TKA should be achieved at least in 2 of 3 zones (joint surface, metaphysis, diaphysis) as shown in Fig. 2.¹⁶ While type I defects <5 mm can be treated by using cement augmentation or impaction bone grafting, defects >5 mm as well as type II a defects should be addressed by wedges.²⁵ Larger defects AORI type IIb and type III usually require additional cones or sleeves for metaphyseal reconstruction. Hereby, the metaphysis can be used for fixation in zone 2, as it may reduce stress shielding and improve rotational stability, compared to diaphysial fixation alone.²⁵^,²⁶^,²⁹ Therefore, metaphyseal fixation using sleeves and cones has gained importance over the last years.

Recommendations following Morgan-Jones et al. for fixation of revision TKA.

1.3

1.3 General concepts of metaphyseal fixation: cones and sleeves

First metaphyseal sleeves were introduced about 40 years ago and were initially combined to a rotating hinge TKA. Over the last decade, material and design improved and cemented as well as cementless sleeves are commonly used in revision TKA – especially when facing complex bone stock lesions AORI type II and III (Fig. 3 and Fig. 4).³⁰ Still there is little long-term data concerning their outcome and survival rate. A recent review by Zanirato et al. demonstrated promising clinical and radiographic short- and mid-term results with an aseptic survival rate of 99.2%.³⁰ Furthermore the use of metaphyseal sleeves without stem in AORI type I and II defect showed good short term follow-up and is suggested to decrease the risk for “end-of-stem-pain”.²⁷ Another point is, that sleeves require an optimal press fit in the metaphysis. Thus, optimal positioning might be challenging as the shape of the defect impacts the sleeve's position. As there is usually no offset option using sleeves it is not always possible to find a perfect position of stem as well as sleeve (Fig. 5). It should also be recognized, that sleeves are usually implant specific and it is therefore advocated that they cannot be combined with alternating TKA-systems.

Sleeves of Revision Knee System Attune® Revision by DePuySynthes – with kind permission of DePuySynthes; source: DePuy Synthes.

Case of a 65 year old women with metaphyseal tibial defect after tibial head fracture of the right knee. After implant removal metaphyseal defect was addressed by a cementless sleeve and stem combination.

Conflict between perfect stem and sleeve position as press fit of the sleeve is influenced by the shape of the bone defect and may not fit the perfect anatomical axis of prepared stem position.

Cones have been used in hip arthroplasty since the late 90s but gained in importance in TKA only over the last decade. They are mainly used in AORI type II and III defects for metaphyseal reconstruction and allow flexible handling in combination with TKA (Fig. 6).⁵ Cones do not need a tight fit with the TKA and they allow a better modularity as they are adaptable to any TKA system, compared to sleeves. Notably, no consensus has been reached whether to use sleeves or cones, which is predominantly due to paucity of mid- and long-term results in current literature.

Cones allow a better modularity as they are adaptable to any TKA system – with kind permission of Waldemar Link GmbH & Co.KG; source: Waldemar Link GmbH & Co.KG.

Handling cones, the metaphyseal portion of the TKA is commonly cemented to the cone, both in cemented and cementless stems in a hybrid technique. Regarding material properties, cones are either made out of highly porous tantalum or titanium. Whereas tantalum cones were first used of about 20 years ago, titanium cones were just developed within the last years to address certain technical limitations of tantalum cones which will be described in the following.

1.4

1.4 Results of tantalum cones

Tantalum cones are fabricated in a Trabecular Metal Technology (TMT) (98% Tantalum, 2% Carbon), showing a low stiffness (elasticity 3 GPa) and a high coefficient of friction,⁶ which may promote metaphyseal fixation and bone ingrowth.²⁴

Even though TMT cones have been used in hip arthroplasty since the late 90ies, there is little corresponding long-term TKA literature by now. A recent systematic review by Zanirato et al. was able to include 21 articles examining 927 cones used in AORI type IIb and III defects in total.³¹ The aseptic survivorship was 97.3% after an average follow-up of 3.6 years. Yet, only 4 out of 21 studies reported a follow-up longer than 5 years.⁷^,¹⁴^,¹⁹^,²²^,³¹ Potter et al. examined 159 femoral TMT cones with a mean follow up of 5 years.¹⁹ At final follow-up, 23 of 159 TKA (14.5%) had been revised due to septic (n = 14) and aseptic (n = 6) loosening or ligamentous instability (n = 3). De Martino et al. showed good bone ingrowth of TMT cones 6 years after revision TKA (n = 18).⁷ Only 2 cases had to be revised due to recurrent infection, yet none due to aseptic loosening. Kamath et al. reported a revision free survival rate of 95% 6 years after tibial metaphyseal reconstruction in revision TKA.¹⁴ There was only one revision due to aseptic loosening. Another study from 2013 also showed excellent results without any radiolucency of the used cones 7 years after revision TKA.¹⁷ All these studies showed major clinical improvement of patient related outcome scores after revision TKA. Roach et al. reported an overall rate of 1.7% of tantalum cones in revision TKA due to aseptic loosening.²⁰ However, there is only one retrospective study examining minimum 10 years follow up using TMT cones in combination with hinged knees for revision arthroplasty.¹ After an average follow-up of 10.5 years, 24 of 32 cones (75%) had survived without any exchange in 18 patients. Reasons for cone revision included aseptic loosening (5/32 cones; 15.6%) and periprosthetic joint infection (3/32 cones; 9.4%).

Although porous tantalum cones have shown high success rates in the existing literature (Table 1), proper preparation of bone stock to match the chosen implant remains challenging. The special structure of TMT allows intraoperative adaption of the TMT-cone by the surgeon himself to achieve a better fitting. However, as this manipulation might damage TMT cones’ structure, one has to be aware of an off-label use. Nevertheless, Zaniratio et al. reported 3% intraoperative fractures while preparing metapyseal bone stock for cones.³¹ Therefore, porous titanium metaphyseal cones (Fig. 7) have been designed based on an anatomical database.¹¹

Table 1 Mid- and long-term survival of cones in the treatment of metaphyseal bone defects.

	n	Follow-up [month]	Survival rate	Aseptic loosening
Potter et al. 2016¹⁹	159	60	86%	3.8%
De Martino et al. 2015⁷	26	72	92%	0%
Kamath et al. 2019¹⁴	66	70	95%	1.5%
Panni et al. 2013¹⁷	9	84	100%	0%
Roach et al. 2020²⁰Review	701	38	82.3%	1.7%
Abdelaziz et al. 2019¹	32	126	75%	15.6%^a

a Cones were combined to total hinge Knee Arthroplasty in 4 out of 5 cases.

Titanium cone - with kind permission of Waldemar Link GmbH & Co.KG; source: Waldemar Link GmbH & Co.KG.

1.5

1.5 Results of titanium cones

The stability of the newer titanium cones showed either equivalent or less micromotion than the tantalum cones in biomechanical studies.¹¹ Of note there are very few short-term results in literature. Nonetheless, they demonstrate good clinical results and comparable survival rates to TMT cones.⁸^,²⁸ Denehy et al. reported an overall revision-free survival rate of 90.2% after 27 months. If infection was excluded, survivorship was 100%.⁸

1.6

1.6 Comparison of TMT and titanium cones

Schildhauer et al. examined bacterial adherence of titanium and tantalum.²³ Bacterial colonisation was quantitatively evaluated by fluorescence microscopy and qualitatively by an electron microscope. The authors were able to show significant less Staphylococcus aureus and Staphylococcus epidermidis colonisation of tantalum compared to titanium which might represent an advantage to TMT cones in septic revisions.

Another advantage of TMT cones is the possibility to adapt the cones shape to the situs by the surgeon himself due to the trabecular structure. As original structure is changed this represents an “off-label-use”.

Notwithstanding the chosen material, highly porous cones show good short to mid-term results in revision TKA as they facilitate metaphyseal fixation. While tantalum cones show good mid-term results with a promising overall survival rate >90% (especially when excluding infection) they are advocated to be more difficult to implant. By comparison, titanium cones show similar biomechanical abilities than tantalum cones while offering easier handling.

By implication, size and shape of the bony defect as well as the surgeon's preference still determine the type of cone, as mid-term results of both materials are comparable and long-term results for titanium cones are pending.

1.7

1.7 Survivorship of cone and sleeve fixation vs. traditional fixation

Before development of sleeves and cones usually cemented stems or a “hybrid technique” was used to manage metaphyseal defects.⁴ The latter uses a cementless, diaphyseal-engaging stem but cement throughout the metaphysis and undersurface of the tibial component and has reports of excellent 5- and 10-year survivorship in aseptic revision TKA.⁹^,¹²^,¹⁸^,²¹ However, up to know there is no literature comparing long term survivorship between modern and traditional fixation techniques in revision TKA. Only one study by Gilliand et al. compared mid-term survivorship of sleeves and hybrid technique in revision TKA 3.5 years after revision surgery.¹² No significant difference was found.

Furthermore, there is only little literature comparing survival rates of sleeves and cones used in TKA revision. A recent metaanalysis by Roach et al. showed similar results concerning survivorship for TMT cones (1.7%) and sleeves (0.8%).²⁰

2

2 Conclusion

Revision TKA often is challenging due to severe bony defects limiting optimal TKA position and fixation which are known risk factors for reduced implant survival.³ While defects AORI I can usually be handled by cement augmentation or wedges, AORI defects II-III requires metaphyseal support. The latter can be achieved using sleeves or cones. Sleeves themselves show good osteointegration when implanted with optimal press-fit, so they can be used without stems. This represents an advantage especially in posttraumatic cases with pathological diaphyseal axis of femur or tibia. On the other hand, perfect position is determined by the shape of the bone defect and is often not fitting the perfect position of the stem. This problem regularly results in a resection of more metaphyseal bone in order to improve implant position. A future solution would be the development of TKA systems which allow a combination of sleeves with offset options. In general, cones allow a more flexible positioning as well as a better modularity as they are adaptable to any TKA system. Up to know there is only little literature comparing the outcome of TMT and titanium cones.

There is no consensus in whether sleeves or cones provide better mid- or long-term outcomes. As both systems shows certain advantages and limitations the decision depends on size and shape of the bony defect as well as surgeons’ preference and experience.

References

Abdelaziz H., Jaramillo R., Gehrke T., Ohlmeier M., Citak M., . Clinical survivorship of aseptic revision total knee arthroplasty using hinged knees and tantalum cones at minimum 10-year follow-up. J Arthroplasty. 2019;34:3018-3022.
[Google Scholar]
Agarwal S., Azam A., Morgan-Jones R., . Metal metaphyseal sleeves in revision total knee replacement. Bone Joint Lett J. 2013;95-B:1640-1644.
[Google Scholar]
Bae D.K., Song S.J., Heo D.B., Lee S.H., Song W.J., . Long-term survival rate of implants and modes of failure after revision total knee arthroplasty by a single surgeon. J Arthroplasty. 2013;28:1130-1134.
[Google Scholar]
Bohl D.D., Brown N.M., McDowell M.A., et al . Do porous tantalum metaphyseal cones improve outcomes in revision total knee arthroplasty? J Arthroplasty. 2018;33:171-177.
[Google Scholar]
Boureau F., Putman S., Arnould A., Dereudre G., Migaud H., Pasquier G., . Tantalum cones and bone defects in revision total knee arthroplasty. Orthop Traumatol Surg Res. 2015;101:251-255.
[Google Scholar]
Cohen R., . A porous tantalum trabecular metal: basic science. Am J Orthoped. 2002;31:216-217.
[Google Scholar]
De Martino I., De Santis V., Sculco P.K., D'Apolito R., Assini J.B., Gasparini G., . Tantalum cones provide durable mid-term fixation in revision TKA. Clin Orthop Relat Res. 2015;473:3176-3182.
[Google Scholar]
Denehy K.M., Abhari S., Krebs V.E., et al . Metaphyseal fixation using highly porous cones in revision total knee arthroplasty: minimum two year follow up study. J Arthroplasty. 2019;34:2439-2443.
[Google Scholar]
Edwards P.K., Fehring T.K., Hamilton W.G., Perricelli B., Beaver W.B., Odum S.M., . Are cementless stems more durable than cemented stems in two-stage revisions of infected total knee arthroplasties? Clin Orthop Relat Res. 2014;472:206-211.
[Google Scholar]
Engh G.A., Ammeen D.J., . Bone loss with revision total knee arthroplasty: defect classification and alternatives for reconstruction. Instr Course Lect. 1999;48:167-175.
[Google Scholar]
Faizan A., Bhowmik-Stoker M., Alipit V., et al . Development and verification of novel porous titanium metaphyseal cones for revision total knee arthroplasty. J Arthroplasty. 2017;32:1946-1953.
[Google Scholar]
Gililland J.M., Gaffney C.J., Odum S.M., Fehring T.K., Peters C.L., Beaver W.B., . Clinical & radiographic outcomes of cemented vs. diaphyseal engaging cementless stems in aseptic revision TKA. J Arthroplasty. 2014;29:224-228.
[Google Scholar]
Hilgen V., Citak M., Vettorazzi E., et al . 10-year results following impaction bone grafting of major bone defects in 29 rotational and hinged knee revision arthroplasties: a follow-up of a previous report. Acta Orthop. 2013;84:387-391.
[Google Scholar]
Kamath A.F., Lewallen D.G., Hanssen A.D., . Porous tantalum metaphyseal cones for severe tibial bone loss in revision knee arthroplasty: a five to nine-year follow-up. J Bone Joint Surg Am. 2015;97:216-223.
[Google Scholar]
Kurtz S., Ong K., Lau E., Mowat F., Halpern M., . Projections of primary and revision hip and knee arthroplasty in the United States from 2005 to 2030. J Bone Joint Surg Am. 2007;89:780-785.
[Google Scholar]
Morgan-Jones R., Oussedik S.I., Graichen H., Haddad F.S., . Zonal fixation in revision total knee arthroplasty. Bone Joint Lett J. 2015;97-B:147-149.
[Google Scholar]
Panni A.S., Vasso M., Cerciello S., . Modular augmentation in revision total knee arthroplasty. Knee Surg Sports Traumatol Arthrosc. 2013;21:2837-2843.
[Google Scholar]
Peters C.L., Erickson J., Kloepper R.G., Mohr R.A., . Revision total knee arthroplasty with modular components inserted with metaphyseal cement and stems without cement. J Arthroplasty. 2005;20:302-308.
[Google Scholar]
Potter G.D., Abdel M.P., Lewallen D.G., Hanssen A.D., . Midterm results of porous tantalum femoral cones in revision total knee arthroplasty. J Bone Joint Surg Am. 2016;98:1286-1291.
[Google Scholar]
Roach R.P., Clair A.J., Behery O.A., Thakkar S.C., Iorio R., Deshmukh A.J., . Aseptic loosening of porous metaphyseal sleeves and tantalum cones in revision total knee arthroplasty: a systematic review. J Knee Surg 2020
[Google Scholar]
Sah A.P., Shukla S., Della Valle C.J., Rosenberg A.G., Paprosky W.G., . Modified hybrid stem fixation in revision TKA is durable at 2 to 10 years. Clin Orthop Relat Res. 2011;469:839-846.
[Google Scholar]
Sandiford N.A., Misur P., Garbuz D.S., Greidanus N.V., Masri B.A., . No difference between trabecular metal cones and femoral head allografts in revision TKA: minimum 5-year followup. Clin Orthop Relat Res. 2017;475:118-124.
[Google Scholar]
Schildhauer T.A., Robie B., Muhr G., Koller M., . Bacterial adherence to tantalum versus commonly used orthopedic metallic implant materials. J Orthop Trauma. 2006;20:476-484.
[Google Scholar]
Sculco P.K., Abdel M.P., Hanssen A.D., Lewallen D.G., . The management of bone loss in revision total knee arthroplasty: rebuild, reinforce, and augment. Bone Joint Lett J. 2016;98-B:120-124.
[Google Scholar]
Senturk U., Perka C., . [Fixation techniques in revision TKA with poor bone conditions. Bone, cement, stem, sleeve, or cone?] Z für Orthop Unfallchirurgie. 2018;156:711-717.
[Google Scholar]
Sheth N.P., Bonadio M.B., Demange M.K., . Bone loss in revision total knee arthroplasty: evaluation and management. J Am Acad Orthop Surg. 2017;25:348-357.
[Google Scholar]
Stefani G., Mattiuzzo V., Prestini G., . Revision total knee arthroplasty with metaphyseal sleeves without stem: short-term results. Joints. 2017;5:207-211.
[Google Scholar]
Tetreault M.W., Perry K.I., Pagnano M.W., Hanssen A.D., Abdel M.P., . Excellent two-year survivorship of 3D-printed metaphyseal cones in revision total knee arthroplasty. Bone Joint Lett J. 2020;102-B:107-115.
[Google Scholar]
Whittaker J.P., Dharmarajan R., Toms A.D., . The management of bone loss in revision total knee replacement. J Bone Joint Surg Br. 2008;90:981-987.
[Google Scholar]
Zanirato A., Cavagnaro L., Basso M., Divano S., Felli L., Formica M., . Metaphyseal sleeves in total knee arthroplasty revision: complications, clinical and radiological results. A systematic review of the literature. Arch Orthop Trauma Surg. 2018;138:993-1001.
[Google Scholar]
Zanirato A., Formica M., Cavagnaro L., Divano S., Burastero G., Felli L., . Metaphyseal cones and sleeves in revision total knee arthroplasty: two sides of the same coin? Complications, clinical and radiological results-a systematic review of the literature. Musculoskelet Surg. 2020;104:25-35.
[Google Scholar]