|Year : 2022 | Volume
| Issue : 1 | Page : 1-5
Implant factors that might influence components' survival in primary total hip arthroplasty
Mohammed Inuwa Maitama1, Yau Zakari Lawal1, Ismaila Lawal Dahiru1, Ibrahim Abolaji Alabi2, Kenneth Ezenwa Amaefule1, Simpa Siaka Audu1, Aniko Ibrahim1
1 Department of Trauma and Orthopedic Surgery, Ahmadu Bello University Zaria, Kaduna State, Nigeria
2 Department of Trauma and Orthopedic Surgery, National Orthopedic Hospital Dala, Kano State, Nigeria
|Date of Submission||26-Oct-2021|
|Date of Decision||17-Nov-2021|
|Date of Acceptance||04-Jan-2022|
|Date of Web Publication||28-Jan-2022|
Dr. Mohammed Inuwa Maitama
Department of Trauma and Orthopedic Surgery, Ahmadu Bello University Zaria, Kaduna State
Source of Support: None, Conflict of Interest: None
Primary total hip arthroplasty (THA) is an invaluable surgical procedure that has revolutionised the treatment of various end-stage hip pathologies. Aseptic loosening of either acetabular cup and/or femoral stem as well as components' dislocation are well-known post-operative complications due to so many factors: environmental, surgeon, patient related, disease related or implant design. The aim of this literature review is to look at some relevant implant designs that might influence acetabular and femoral components' survival for primary cementless THA using revision for aseptic loosening and dislocation as criteria for failure. This may also assist the surgeon in making an informed choice of using appropriate implants to match the demographic and disease-specific need of the patients undergoing the surgical procedure. This review article was performed using an online literature search on relevant publications.
Keywords: Aseptic loosening, component's dislocation, implants design, survivorship
|How to cite this article:|
Maitama MI, Lawal YZ, Dahiru IL, Alabi IA, Amaefule KE, Audu SS, Ibrahim A. Implant factors that might influence components' survival in primary total hip arthroplasty. Niger Postgrad Med J 2022;29:1-5
|How to cite this URL:|
Maitama MI, Lawal YZ, Dahiru IL, Alabi IA, Amaefule KE, Audu SS, Ibrahim A. Implant factors that might influence components' survival in primary total hip arthroplasty. Niger Postgrad Med J [serial online] 2022 [cited 2022 Sep 28];29:1-5. Available from: https://www.npmj.org/text.asp?2022/29/1/1/336747
| Introduction|| |
Aseptic loosening and components' dislocation are well-recognised post-operative complications following total hip replacement. The ultimate goal of any arthroplasty surgeon is to use the best of components' combination in the face of other risk factors for failure to achieve the longest possible survivorship which according to the NICE guidelines is at least 90% at 10 years. Modifications in implant design have continued to evolve over time, and still evolving, to match the special need in young active individuals, obese patients, those with congenital or acquired bone defects, musculoskeletal and neurological disorders as well as elderly osteoporotic patients. Word of caution may need to be sounded at some of these latest designs that give excellent early results, because of the need for more period of evaluation in order to assess their long-term safety profile.
| Material Consideration|| |
Commonly used arthroplasty metallic prosthesis includes stainless steel, titanium and cobalt chrome (Co-Cr) alloys each with different biomechanical properties. One of the earliest modern material alloys to be widely used for orthopaedic implants was stainless steel due to its relatively high strength, cost and easy workability. Stainless steel can be polished to a relatively high smoothness which decreases abrasive wear on polyethylene bearing surfaces and has been used as femoral heads. It is less frequently used nowadays as arthroplasty material, because of its poor biocompatibility. Co-Cr alloy is now more frequently utilised for hip prostheses particularly as cemented stems due to its high ultimate strength, easily workable and relatively resistant to corrosion, but because of its higher bending stiffness, it may contribute significantly to stress shielding. Chromium is added to stainless steel and cobalt to contribute to hardness and resistance to oxidation. However, chromium ions released during corrosion of stainless steel and Co-Cr alloy may have caused DNA and chromosomal damage in the body. Titanium and its alloys are popular metallic implant biomaterials in use due to its superior biocompatibility and relatively lower elastic modulus that is closer to cortical bone than other choices, thus reducing the problem of stress shielding. It is corrosion resistant due to the formation of a protective titanium oxide layer on the surface and the ease for its surface modification for osseointegration. Titanium alloys are, however, not suitable for manufacturing of femoral head due to their poor scratch resistance and are generally expensive. Vanadium added to titanium alloy, with a view to enhancing its corrosion resistance, is no longer in use due to toxicity of vanadium ion to the body. Research is still ongoing for developing newer metallic alloys that match excellent biocompatibility with superior mechanical properties to meet up with qualities of an ideal metallic implant.
| Components' Surface Bearing|| |
Metal-on-polyethylene (MoP) combination of bearing surfaces was developed by Sir John Charnley using stainless steel and conventional polyethylene liner. Its main complication is that of large particulate polyethylene debris generation and deposition within the joint space, stimulating an osteolytic reaction. The incidence of osteolysis in this conventional polyethylene was almost 18%. This prompted its manufacturing modification to highly cross-linked polyethylene (XLPE) that offers improved resistance to adhesive and abrasive wear. That notwithstanding, metal-on-PE bearings are still considered to have higher wear rates when compared to hard-on-hard bearing surfaces, even though these alternative bearings were developed and used before the short-to-medium-term results of highly cross-linked polyethylene were reported. Hard-on-hard materials such as ceramic-on-ceramic (CoC) and metal-on-metal (MoM) coupling surfaces were designed to partially solve the problems of polyethylene wear debris generation by offering tolerance to high impact loading, improvement of surface hardness and resistance to abrasive wear to improve survivorship and reduce the risk of revision surgery. It is estimated that the wear rate of MoM was about 60 times less than that of conventional MoP. Ceramic bearings have lesser risk of developing particulate debris, osteolysis and loosening due to their surface hardness, scratch resistance and wettability,, exhibiting the best wear properties of all total joint bearing surfaces. Likewise, ceramic on polyethylene has shown to have good wear resistance, for example, zirconium-on-polyethylene articulations had lower acetabular revision rates compared with cobalt chrome on polyethylene. Main disadvantage of CoC is failure from material fracture and squeaking. In fact, accelerated acetabular wear has been reported in a squeaking ceramic-on-ceramic hip. The risk of fracture with ceramic components has, however, been reduced with modern technology and manufacturing modifications. Metal-on-metal hip arthroplasty may have been associated with high implant failure rates,, due to adverse reactions to metal debris characterised by solid pseudo-tumour formation, tissue necrosis and subsequent component loosening that represents the most common mode of its failure. Raised level of serum ions is another safety concern. Few centres have previously reported encouraging survivorship particularly in young active population,,, but despite these impressive results, complications of metal on metal and the risk of fracture in ceramic-on-ceramic bearings have questioned the rationale and safety of the principles of hard-on-hard bearings. Most authors have discouraged the use of hard-on-hard alternative bearings, and most countries, including the United States, have stopped using MoM bearing surfaces for stemmed total hip arthroplasty (THA). This leads to sharp decline in MoM THA. There has been an attempt to quote metallic head with ceramic (Ceramicised metal ball) so as to have the best of both metal and ceramic properties by minimising risk of fracture, squeaking and metal ion deposit while offering material hardness of metal and superior wear resistance of ceramic, thereby meeting the requirement of young active patients. Oxinium femoral heads, although not strictly ceramic quoting but metal surface that is transformed to ceramic, are an example of this new hybrid technology. Zirconia-reinforced alumina also minimises fracture risks of ceramic heads. Of recent, Davis et al. have found the lowest risk of revision in all and specific young age group of ceramicised metallic head on high cross-linked polyethylene compared to CoXLPE and MoXLPE at 13-year follow-up with CoC and CoXLPE not differing significantly from MoXLPE.
| Constrained Liner|| |
Constrained liners are special designs with locking mechanism on the liner that capture the metallic femoral head preventing it from dislocating under routine physiologic range of hip motion. There are various types based on manufacturing specifications but basically consist of specially designed polyethylene liner with a locking ring that gives the constrained articulation with metallic head. Suitable in elderly and patients with paralytic and neuromuscular disorders, who carry special risk of post operative dislocation. It is very effective in preventing post-operative dislocation. However, higher forces are transmitted through the constrained articulation due to limited range of motion and possible impingement that may lead to failure in form of cup loosening, cup liner micro-motion with back side wear or locking mechanism failure. Impingement damage to the rim of the polyethylene liner was virtually seen in all retrievals. Many authors,, have reported the satisfactory outcome of constrained liners in terms of preventing components' dislocation in high-risk patients when adjusted for other compounding variables like incorrect cup positioning.
| Dual-Mobility Cup|| |
The idea of dual-mobility cup was first introduced in the 1970s by Bousquet et al. with the aim of minimising components' dislocation. It has since undergone lots of modifications and improvement from the initial design. Compared with traditional component couplings, it is commonly designed with additional bearing surface consisting of metallic head articulating into a mobile polyethylene liner, thereby expanding the effective head diameter and increasing the surface area between mobile liner and acetabular cup, minimising risk of implant dislocation in obese and elderly with weak abductor mechanism. It also offers a high range of motion in young active patients without compromising stability of fixation. Presence of dual motion may have also offered a lower wear rate and minimises the incidence of prosthetic neck impingement, thereby adding positively to the chances of components' survival. Philippot et al. have reported a survival rate of dual-mobility cup of 77% in patients under 50 years of age at 22-year follow-up. Assi et al. have reported excellent clinical and radiological results of patients at high risk of dislocation with very few complications. Approved for use in the USA by the FDA since 2009, Harwin et al. in assessing 5–7-year performance of dual-mobility cup for primary hip arthroplasty have reported excellent overall clinical and patient satisfaction with all-cause survivorship of 98.6% using Kaplan–Meier analysis. Cypres et al. have published satisfactory dual-mobility cup survival of 95.9% at 11.9 years using revision for any reason as end point.
| Femoral Head Size|| |
There are various sizes of femoral head prostheses in use ranging from 22 mm to 36 mm up to 40 mm. Advantages of using large head diameter like 32 mm and 36 mm include decreased risk of dislocation and neck cup impingement, thereby improving overall range of motion and stability. Its main disadvantage is that of increase in liner wear due to large contact surface area particularly on previous old generation polyethylene liners. However, this risk of volumetric wear has been reduced overtime due to development of XLPE, thereby reintroducing the relevance of large femoral heads once again. The main problem at present is decreasing actual liner thickness to accommodate larger heads, which is even impracticable in smaller size acetabular replacements. The use of small femoral head, from earlier time, was popularised by Sir John Charnley, a concept that was designed to follow the rationale of low friction arthroplasty, thereby decreasing frictional torque at bearing surfaces and minimising polyethylene wear. The main drawback is that of high incidence of dislocation with as high as 66% occurring in the 1st year. Tsikandylakis et al. have found the risk of revision due to dislocation to be lower for 36 mm or larger head compared with 28 mm or smaller but with increased volumetric wear and frictional torque in bearings bigger than 32 mm compared with 32 mm or smaller in metal-on-cross-linked polyethylene. Based on his study, he recommend using size 32mm metallic ball as the best balance between implant stability on one hand, and liner volumetric wear on the other. Several researchers have reported a good correlation between bigger head size and improved stability but at a slight cost of increasing liner wear.,,,,,,,
| Collared versus Collar Less Femoral Stems|| |
Femoral stem with medial collar is designed to give better mechanical seating and compressive loading on calcar femorale. This helps in impacting resistance to early stem subsidence before adequate osseointegration takes place, particularly in overweight patients and those with very wide medullary canal, compared to collarless femoral stems. A collar on the calcar may also have reduced the risk of an early periprosthetic fracture on non-cemented stems. Chitnis et al., in evaluating the mid-term performance of medial collared cementless stem designs, have found a statistically significant difference in cumulative incidences for all-cause revisions between the collared hip and other conventional stems. Some authors, on the other hand, have investigated the benefits or otherwise of collared stems and found little or no differences, in either short-or long-term outcomes, when compared to collarless stems.,
| Proximally Versus Fully Coated Femoral Stems|| |
There are basically two types of non-cemented femoral stems with respect to the extent of coating or porosity for bony ingrowth: proximally coated/porous and fully coated/porous stems. Fully coated stems achieve bony ingrowth throughout its entire length due to the larger surface area of coating giving a more rigid fixation that is metaphyseo-diaphyseal in nature, which is presumably desirable for long time clinical performance and has been reported as such. Fully coated stems may also have sealed the potential space between implant and bone, preventing movement of particles from cup wear into the periprosthetic bone-implant spaces theoretically minimising femoral component loosening. However, this design may lead to stress shielding and proximal femoral (trochanteric) bone loss on account of greater load transfer distally with potential complication of greater trochanteric avulsion fractures. It also makes it difficult to remove during extraction for non-loosening revisions as compared to proximally coated types. Fully coated stems are reported to perform satisfactorily in patients with proximal femoral osteopenia due to aging or disease process, in periprosthetic fracture or in revision setting with proximal femoral bone loss if cemented femoral revision is not decided. The rationale behind proximal coating is to partially solve the problem of stress shielding and other demerits as seen with fully coated stems. It is designed to load the femur proximally, thereby giving fixation that is metaphyseal and allowing more physiologic load transfer to diaphysis, suitable for young active individuals with high physical demands. However, Jacobs and Christensen have reported, considering other variables, progressive subsidence using a tapered, proximally coated stems as a remote complication.
| Hydroxyapatite versus Trabecular Metal Porous Surfaces|| |
There are different types of calcium phosphate coatings, of which hydroxyapatite (HA) gives the most consistent and reliable result in providing durable bone ingrowth fixation. It offered advantages of good biocompatibility, excellent bony ingrowth and occasional formation of bone bridge at macroscopic gaps between host bone and coated femoral stem. These qualities make it an excellent material for cementless coatings and survival outcomes. Its purity, porosity and coating thickness differ amongst various manufacturers which might influence the results of its long-term outcome. There are concerns of possible dissolution of HA layer in vivo after 8 years of implantation leading to delamination, loosening and subsequent failure. Trabecular metal (TM) cups and stems are fabrications on the surface of the metal giving it extensive porosity, like trabecular bone, in its structure and weight-bearing characteristics, thereby enabling rapid and extensive bone infiltration. Compared to HA coating, it has the theoretical advantage of offering intrinsically high coefficient of friction against the cancellous bone and scratch-fit stability leading to reliably long-term fixation. Delamination seen with HA as a complication is almost non-existence in TM stems because of their ability to accommodate lengthier and more interconnected trabecular bony ingrowth without compromising bone interface shear strength. It also provides inherent flexibility similar to bone, thereby minimising potential for stress shielding. Many authors have reported the excellent outcome of TM cups both in primary, and revision, arthroplasty.
| Conclusion|| |
From the above review, it is clear that some implant designs or material combinations, when performing primary THA, are more suitable to select and use, giving a peculiar situation for better chances of longer components' survival. That notwithstanding, several authors have reported conflicting results with different types of implant design, with some having excellent long-term outcome and others reporting otherwise. This underscores the fact that other confounding variables (environmental, surgical and patient related) also need to be taken into consideration to have adjusted results and more accurate conclusions.
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Conflicts of interest
There are no conflicts of interest.
| References|| |
Excellence NIFC. Guidance on Selection of Prostheses for Primary Total Hip Replacement. London. Technology Appraisal Guidance; 2000. p. 2.
Hu CY, Yoon TR. Recent updates for biomaterials used in total hip arthroplasty. Biomater Res 2018;22:33.
Merritt K, Brown SA. Release of hexavalent chromium from corrosion of stainless steel and cobalt-chromium alloys. J Biomed Mater Res 1995;29:627-33.
Mirza SB, Dunlop DG, Panesar SS, Naqvi SG, Gangoo S, Salih S. Basic science considerations in primary total hip replacement arthroplasty. Open Orthop J 2010;4:169-80.
Catalani S, Stea S, Beraudi A, Gilberti ME, Bordini B, Toni A, et al.
Vanadium release in whole blood, serum and urine of patients implanted with a titanium alloy hip prosthesis. Clin Toxicol (Phila) 2013;51:550-6.
Hanna SA, Somerville L, McCalden RW, Naudie DD, MacDonald SJ. Highly cross-linked polyethylene decreases the rate of revision of total hip arthroplasty compared with conventional polyethylene at 13 years' follow-up. Bone Joint J 2016;98-B:28-32.
Glyn-Jones S, Thomas GE, Garfjeld-Roberts P, Gundle R, Taylor A, McLardy-Smith P, et al.
The John Charnley award: Highly crosslinked polyethylene in total hip arthroplasty decreases long-term wear: A double-blind randomized trial. Clin Orthop Relat Res 2015;473:432-8.
Schmalzried T, Kwong L, Jasty M. Periprosthetic bone loss in total hip arthroplasty: The role of polyethylene wear debris and the concept of the effective joint space. J Bone Joint Surg Am 1992;74:849-63.
Cuckler JM. The rationale for metal-on-metal total hip arthroplasty. Clin Orthop Relat Res 2005;441:132-6.
Zywiel MG, Sayeed SA, Johnson AJ, Schmalzried TP, Mont MA. Survival of hard-on-hard bearings in total hip arthroplasty: A systematic review. Clin Orthop Relat Res 2011;469:1536-46.
Traina F, De Fine M, Di Martino A, Faldini C. Fracture of ceramic bearing surfaces following total hip replacement: A systematic review. Biomed Res Int 2013;2013:157247.
Lusty PJ, Watson A, Tuke MA, Walter WL, Walter WK, Zicat B. Wear and acetabular component orientation in third generation alumina-on-alumina ceramic bearings: An analysis of 33 retrievals [corrected]. J Bone Joint Surg Br 2007;89:1158-64.
Kearns SR, Jamal B, Rorabeck CH, Bourne RB. Factors affecting survival of uncemented total hip arthroplasty in patients 50 years or younger. Clin Orthop Relat Res 2006;453:103-9.
Laurent MP, Pourzal R, Fischer A, Bertin KC, Jacobs JJ, Wimmer MA. In vivo
wear of a squeaky alumina-on-alumina hip prosthesis: A case report. J Bone Joint Surg Am 2011;93:e27.
Smith AJ, Dieppe P, Vernon K, Porter M, Blom AW; National Joint Registry of England and Wales. Failure rates of stemmed metal-on-metal hip replacements: Analysis of data from the National Joint Registry of England and Wales. Lancet 2012;379:1199-204.
Umar M, Jahangir N, Malik Q, Kershaw S, Barnes K, Morapudi S. Long-term results of metal on metal total hip arthroplasty in younger patients (<55yrs). J Orthop 2018;15:586-90.
Langton DJ, Sidaginamale RP, Avery P, Waller S, Tank G, Lord J, et al.
Retrospective cohort study of the performance of the pinnacle metal on metal (MoM) total hip replacement: A single-centre investigation in combination with the findings of a national retrieval centre. BMJ Open 2016;6:e007847.
Erivan R, Villatte G, Millerioux S, Mulliez A, Descamps S, Boisgard S. Survival at 11 to 21 years for 779 Metasul® metal-on-metal total hip arthroplasties. J Orthop Surg (Hong Kong). 2020;28(2):2309499020926265. doi:10.1177/2309499020926265.
Brown SR, Davies WA, DeHeer DH, Swanson AB. Long-term survival of McKee-Farrar total hip prostheses. Clin Orthop Relat Res. 2002;(402):157-163. doi:10.1097/00003086-200209000-00013.
Long WT. The clinical performance of metal-on-metal as an articulation surface in total hip replacement. Iowa Orthop J 2005;25:10-6.
Erivan R, Villatte G, Lecointe T, Mulliez A, Descamps S, Boisgard S. Long-term survival of hybrid total hip arthroplasty with the uncemented CLS cup, cemented Müller cobalt-chromium stem, and 28-mm Metasul™ bearings: Retrospective review of 115 hips after a minimum of 17.8 years. Orthop Traumatol Surg Res 2019;105:1289-95.
Silverman EJ, Ashley B, Sheth NP. Metal-on-metal total hip arthroplasty: is there still a role in 2016?. Curr Rev Musculoskelet Med. 2016;9(1):93-96. doi:10.1007/s12178-016-9323-1.
Hunter, Gordon, J. C. Dickinson, Bj Herb and R Graham. “Creation of Oxidized Zirconium Orthopaedic Implants.” Journal of Astm International 2 (2005): 1-14.
Kop AM, Whitewood C, Johnston DJ. Damage of oxinium femoral heads subsequent to hip arthroplasty dislocation three retrieval case studies. J Arthroplasty 2007;22:775-9.
Howard DP, Wall PD, Fernandez MA, Parsons H, Howard PW. Ceramic-on-ceramic bearing fractures in total hip arthroplasty: An analysis of data from the National Joint Registry. Bone Joint J 2017;99-B:1012-9.
Davis ET, Pagkalos J, Kopjar B. Effect of bearing surface on survival of cementless and hybrid total hip arthroplasty: Study of data in the National Joint Registry for England, Wales, Northern Ireland and the Isle of Man. JB JS Open Access 2020;5:e0075.
Su EP, Pellicci PM. The role of constrained liners in total hip arthroplasty. Clin Orthop Relat Res. 2004;(420):122-129. doi:10.1097/00003086-200403000-00017.
Jones SA. Constrained acetabular liners. J Arthroplasty 2018;33:1331-6.
Andersen AV, Kjersgaard AG, Solgaard S. Trilogy-constrained acetabular component for recurrent dislocation. ISRN Orthop 2013;2013:629201.
Bousquet G, Argenson C, Godeneche JL, Cisterne JP, Gazielly DF, Girardin P, et al.
Recovery after aseptic loosening of cemented total hip arthroplasties with Bousquet's cementless prosthesis. Apropos of 136 cases. Rev Chir Orthop Reparatrice Appar Mot 1986;72 Suppl 2:70-4.
Philippot R, Neri T, Boyer B, Viard B, Farizon F. Bousquet dual mobility socket for patient under fifty years old. More than twenty year follow-up of one hundred and thirty one hips. Int Orthop 2017;41:589-94.
Assi C, Barakat H, Mansour J, Samaha C, Yammine K. Primary total hip arthroplasty: Mid-term outcomes of dual-mobility cups in patients at high risk of dislocation. Hip Int 2021;31:174-80.
Bousquet G, Gazielly DF, Debiesse JL, Girardin P, Relave M, Israeli A. The ceramic coated cementless total hip arthroplasty. Basic concepts and surgical technique. J Orthop Surg Tech 1985;1:15.
Harwin SF, Sodhi N, Ehiorobo J, Khlopas A, Sultan AA, Mont MA. Outcomes of dual mobility acetabular cups in total hip arthroplasty patients. Surg Technol Int 2019;34:367-70.
Cypres A, Fiquet A, Girardin P, Fitch D, Bauchu P, Bonnard O, et al
. Long-term outcomes of a dual-mobility cup and cementless triple-taper femoral stem combination in total hip replacement: A multicenter retrospective analysis. J Orthop Surg Res 2019;14:376.
Meek RM, Allan DB, McPhillips G, Kerr L, Howie CR. Late dislocation after total hip arthroplasty. Clin Med Res 2008;6:17-23.
Tsikandylakis G, Mohaddes M, Cnudde P, Eskelinen A, Kärrholm J, Rolfson O. Head size in primary total hip arthroplasty. EFORT Open Rev 2018;3:225-31.
Plate JF, Seyler TM, Stroh DA, Issa K, Akbar M, Mont MA. Risk of dislocation using large- vs. small-diameter femoral heads in total hip arthroplasty. BMC Res Notes 2012;5:553.
Rathi P, Pereira GC, Giordani M, Di Cesare PE. The pros and cons of using larger femoral heads in total hip arthroplasty. Am J Orthop (Belle Mead NJ) 2013;42:E53-9.
Girard J. Femoral head diameter considerations for primary total hip arthroplasty. Orthop Traumatol Surg Res 2015;101:S25-9.
Peters CL, McPherson E, Jackson JD, Erickson JA. Reduction in early dislocation rate with large-diameter femoral heads in primary total hip arthroplasty. J Arthroplasty 2007;22:140-4.
Cho MR, Choi WK, Kim JJ. Current concepts of using large femoral heads in total hip arthroplasty. Hip Pelvis 2016;28:134-41.
Myung RC, Jeong SD, Won KC. Using large femoral head as a bearing surface in total hip arthroplasty. Juniper Online Journal of Orthopedic & Orthoplastic Surgery 2018;2:555578.
Byström S, Espehaug B, Furnes O, Havelin LI; Norwegian Arthroplasty Register. Femoral head size is a risk factor for total hip luxation: A study of 42,987 primary hip arthroplasties from the Norwegian arthroplasty register. Acta Orthop Scand 2003;74:514-24.
Tarasevicius S, Robertsson O, Kesteris U, Kalesinskas RJ, Wingstrand H. Effect of femoral head size on polyethylene wear and synovitis after total hip arthroplasty: A sonographic and radiographic study of 39 patients. Acta Orthop 2008;79:489-93.
Simpson DJ, Kendrick BJ, Hughes M, Glyn-Jones S, Gill HS, Rushforth GF, et al.
The migration patterns of two versions of the Furlong cementless femoral stem: A randomised, controlled trial using radiostereometric analysis. J Bone Joint Surg Br 2010;92:1356-62.
Lamb JN, Baetz J, Messer-Hannemann P, Adekanmbi I, van Duren BH, Redmond A, et al.
A calcar collar is protective against early periprosthetic femoral fracture around cementless femoral components in primary total hip arthroplasty: A registry study with biomechanical validation. Bone Joint J 2019;101-B:779-86.
Chitnis AS, Mantel J, Ruppenkamp J, Bourcet A, Holy CE. Survival analysis for all-cause revision following primary total hip arthroplasty with a medial collared, triple-tapered primary hip stem versus other implants in real-world settings. Curr Med Res Opin 2020;36:1839-45.
Al-Najjim M, Khattak U, Sim J, Chambers I. Differences in subsidence rate between alternative designs of a commonly used uncemented femoral stem. J Orthop 2016;13:322-6.
Meding JB, Ritter MA, Keating EM, Faris PM. Comparison of collared and collarless femoral components in primary uncemented total hip arthroplasty. J Arthroplasty 1997;12:273-80.
Jacquot L, Bonnin MP, Machenaud A, Chouteau J, Saffarini M, Vidalain JP. Clinical and radiographic outcomes at 25-30 years of a hip stem fully coated with hydroxylapatite. J Arthroplasty 2018;33:482-90.
Kraemer WJ, Maistrelli GL, Fornasier V, Binnington A, Zhao JF. Migration of polyethylene wear debris in hip arthroplasties: A canine model. J Appl Biomater 1995;6:225-30.
Nagoya S, Sasaki M, Kaya M, Okazaki S, Tateda K, Yamashita T. Extraction of well-fixed extended porous-coated cementless stems using a femoral longitudinal split procedure. Eur Orthop Traumatol 2015;6:417-21.
Rivera F, Leonardi F, Maniscalco P, Caforio M, Capelli R, Molinari G, et al.
Uncemented fully hydroxyapatite-coated hip stem for intracapsular femoral neck fractures in osteoporotic elderly patients: A multicenter study. Arthroplast Today 2015;1:81-4.
Wang Q, Li D, Kang P. Uncemented extensive porous titanium-coated long femoral stem prostheses are effective in treatment of Vancouver type B2 periprosthetic femoral fractures: A retrospective mid- to long-term follow-up study. J Orthop Surg (Hong Kong). 2019;27(2):2309499019857653. doi:10.1177/2309499019857653.
Sinha RK, Dungy DS, Yeon HB. Primary total hip arthroplasty with a proximally porous-coated femoral stem. J Bone Joint Surg Am 2004;86:1254-61.
Jacobs CA, Christensen CP. Progressive subsidence of a tapered, proximally coated femoral stem in total hip arthroplasty. Int Orthop 2009;33:917-22.
Bloebaum RD, Beeks D, Dorr LD, Savory CG, DuPont JA, Hofmann AA. Complications with hydroxyapatite particulate separation in total hip arthroplasty. Clin Orthop Relat Res. 1994;(298):19-26.
Pedersen DR, Brown TD, Poggie RA. Finite Element Analysis of Periacetabular Stress of Cemented, Metal Backed, and Porous Tantalum Backed Acetabular Components. Presented at: 45th
Annual Meeting Orthopedic Research Society; February 1-4, 1999, Anaheim, CA.
Howard JL, Kremers HM, Loechler YA, Schleck CD, Harmsen WS, Berry DJ, et al.
Comparative survival of uncemented acetabular components following primary total hip arthroplasty. J Bone Joint Surg Am 2011;93:1597-604.
De Martino I, De Santis V, Sculco PK, D'Apolito R, Poultsides LA, Gasparini G. Long-term clinical and radiographic outcomes of porous tantalum monoblock acetabular component in primary hip arthroplasty: A minimum of 15-year follow-up. J Arthroplasty 2016;31:110-4.
Davies JH, Laflamme GY, Delisle J, Fernandes J. Trabecular metal used for major bone loss in acetabular hip revision. J Arthroplasty 2011;26:1245-50.
Mohaddes M, Rolfson O, Kärrholm J. Short-term survival of the trabecular metal cup is similar to that of standard cups used in acetabular revision surgery. Acta Orthop 2015;86:26-31.