- Email: [email protected]
Femoral revision for periprosthetic fracture in total hip arthroplasty
Journal of Clinical Orthopaedics and Trauma xxx (xxxx) xxx
Contents lists available at ScienceDirect
Journal of Clinical Orthopaedics and Trauma journal homepage: www.elsevier.com/locate/jcot
Femoral revision for periprosthetic fracture in total hip arthroplasty Luke G. Menken*, Jose A. Rodriguez Hospital for Special Surgery, 535 E 70th St, 10021, New York, NY, USA
a r t i c l e i n f o
a b s t r a c t
Article history: Received 22 November 2019 Accepted 11 December 2019 Available online xxx
Periprosthetic fracture can create significant morbidity in the arthroplasty population. Patients with periprosthetic fracture have been shown to have worse outcomes and higher mortality than patients undergoing elective revision THA. In this review, we will focus on Vancouver B2 and B3 fractures. Both of these fracture types are associated with a loose primary prosthesis and warrant revision surgery. There are many different options for fixation choice of the femoral prosthesis, and preference has been evolving over the last 30 years. Currently, we use monoblock, tapered, fluted, titanium stems for all periprosthetic fracture revision surgeries. © 2019
Keywords: Revision hip surgery Periprosthetic femur fracture Total hip arthroplasty
1. Introduction
2. Classification
Total hip arthroplasty (THA) is a very successful procedure with expanding indications. As the prevalence of total hip replacements increases, the incidence of short-term and long-term complications is set to increase as well.1 Arthroplasty indications are expanding and they are currently being performed in both older patients with poor bone quality and young patients with high activity demands.2 One complication that has been highly studied and is seen in both patient populations is post-operative periprosthetic fractures. The reported incidence varies between 0.07 and 18%.2e6 These fractures can occur from low energy trauma, stress risers, or even missed intraoperative fractures that propagate post-operatively. Periprosthetic fracture can create significant morbidity in the arthroplasty population. Many factors can affect the risk of sustaining a periprosthetic fracture. Some commonly reported factors increasing risk include age, gender, BMI, component fixation, stem design, surgical approach, primary diagnosis (i.e., avascular necrosis, rheumatoid arthritis), and medical comorbidities that can result in decreased bone density.3e6 Patients with periprosthetic fracture have been shown to have worse outcomes and higher mortality than patients undergoing elective revision THA.7,8 It is essential to develop meticulous technique to promote fracture healing and stable implant integration in order to allow these patients to return to their pre-injury functional level.
Many classification systems have been proposed to describe periprosthetic fractures. However, the most commonly used classification system is the Vancouver classification. The Vancouver classification is a validated system that both describes the fracture pattern and suggests a treatment algorithm for each fracture type.9 The classification is demonstrated in Table 1. In this review, we will focus on Vancouver B2 and B3 fractures. Both of these fracture types are associated with loose primary prosthesis and warrant revision surgery, and these are treated similarly in our practice. Many different reconstructive options are available for surgeons to choose from. Some stem designs include long, cemented stems, fully porous coated stems, tapered, splined, modular or monoblock stems, and proximal femoral replacement prostheses. Currently in our practice, we use tapered, splined monoblock stems for all periprosthetic fracture revisions. We have followed concepts established by Berry of seeking to rest the implant on distal intact bone and reconstructing the proximal femoral fragments around the implant.10
* Corresponding author. E-mail addresses: [email protected] (L.G. Menken), [email protected] (J.A. Rodriguez).
3. Pre-op planning11 The first step in achieving fracture fixation and return to function is a sound, reproducible pre-operative template. It is particularly important in periprosthetic fracture revision to have a concrete plan for fixation because the tissue trauma distorts the typical anatomy. In order to properly template, the surgeon will need to acquire radiographs of the hip and femur in both AP and lateral views. An
https://doi.org/10.1016/j.jcot.2019.12.003 0976-5662/© 2019
Please cite this article as: Menken LG, Rodriguez JA, Femoral revision for periprosthetic fracture in total hip arthroplasty, Journal of Clinical Orthopaedics and Trauma, https://doi.org/10.1016/j.jcot.2019.12.003
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Table 1 Vancouver classification of post-operative periprosthetic femur fractures. Classification A B
C
AG AL B1 B2 B3
Fracture Location
Treatment
Greater trochanter fracture Lesser trochanter fracture Fracture around the prosthesis, stem well fixed Fracture around the prosthesis, stem is loose Fracture around the prosthesis, loose stem and poor proximal bone stock Fracture distal to tip of stem
Non-operative or ORIF Non-operative or ORIF ORIF Revision arthroplasty Revision arthroplasty ORIF
assessment of the existing bone stock should be done at this time in order to determine the best reconstructive option. The surgeon will have to determine the proper center of rotation of the femoral head and set a goal for leg length. Working distally from the desired center of rotation, the surgeon must identify the remaining bone that can provide axial and rotational support for the proposed implant and choose the appropriate size and length to achieve the center of rotation and offset goals. Information for optimal sizing of the stem can be sought on the contralateral side where normal or comparable anatomy is demonstrated. Once the surgeon has used the contralateral side for sizing, the operative side should be assessed. First, the surgeon should identify where the stem was sitting in the femur before the fracture. This can usually be seen in both cemented and uncemented stems status post periprosthetic fracture. Based on this point, the subsidence distance is measured from the distal tip of the prosthesis to the former distal point of the implant position. This distance is then added to the current center of rotation along a superomedial vector (Fig. 1). The distance is marked on the x-ray and will be used in order to determine the proper length of the templated implant. Next, the surgeon should identify the most proximal, identifiable part of the distal fracture fragment. This will be used during the operation as a reference for reamer positioning, in order to achieve the desired leg length. The distance between this bony landmark and the þ0 femoral head mark on template in the desired position within the femur should be measured. During the operation, this distance can be replicated to achieve the proper depth of reaming so that the prosthesis sits in the correct position upon implantation (Fig. 2). If pre-fracture x-rays are available, these can
Fig. 2. Measurement of proximal most portion of the distal fracture fragment at the medial cortex to the planned center of rotation on pre-op x-ray and during the operation.
also be used in order to assess proper stem sizing and positioning on the operative side. The implant sizing and positioning is of paramount importance and should be carefully templated. The tapered, splined, monoblock stem does not gain fixation by 3-point contact but by its placement in the conical, reamed bone bed. There should be a tight press fit of the splines along with 2e4 cm of diaphyseal bone supporting the implant distal to the end of the fracture.12,13 This type of implant gains it stability due to the conical shape of prosthesis, preventing subsidence, and due to the splines, which prevent axial rotation. 4. Surgical technique
Fig. 1. (A) Periprosthetic fracture with clear outline of former implant position (blue arrow). (B) Preoperative plan including measurement of subsidence and adding it to the center of rotation in a superomedial direction for final implant proximal positioning.
There are a number of different options in terms of surgical approach. Most often, the surgery is done through the posterolateral approach; however, the direct anterior approach and anterolateral approach are also options. Typically, we will choose the approach that was used previously in the primary surgery. That way, the capsule is not violated anteriorly and posteriorly, thus maintaining capsular support so as to not detract from the stability of the final construct. Once the femur is exposed, the fracture fragments are used like an osteotomy and any cement or debris can be cleared from the medullary canal. All soft tissue attachments to the fracture fragments should be maintained during the approach so that none of the vascular supply is compromised which will aid later on in fracture healing.10 Proceeding to the femoral preparation, the proximal piece of the distal diaphyseal fragment that was used for templating should first be identified. This will be used to mark the reamer with the predetermined distance that was templated prior to surgery (Fig. 3). A prophylactic cable should be placed distal to the fracture so that there is no fracture propagation during the reaming process (Fig. 4). Once the reamer is marked, the surgeon should double check the depth of the reamer by placing it along the thigh to estimate final placement.
Please cite this article as: Menken LG, Rodriguez JA, Femoral revision for periprosthetic fracture in total hip arthroplasty, Journal of Clinical Orthopaedics and Trauma, https://doi.org/10.1016/j.jcot.2019.12.003
L.G. Menken, J.A. Rodriguez / Journal of Clinical Orthopaedics and Trauma xxx (xxxx) xxx
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Fig. 3. Proximal portion of distal fracture fragment identified and used to measure the templated distance and mark the reamer so that the conically reamed bone bed is at the appropriate depth within the canal.
Fig. 4. Adding a cable distal to the fracture in order to prevent fracture propagation during the reaming process. The distal most aspect of the fracture fragment is seen at the blue arrow.
We perform reaming by hand using fluoroscopy as guidance with the thigh resting on the C-arm, or more commonly mini C-arm detector. The mini C-arm is used for a few reasons, it allows approximation of the templated positioning of the final implant, it allows maneuvering around any femoral defects, and it prevents reaming in an overly anterior direction, which could potentially violate the anterior cortex. Finally, the mini C-arm allows for confirmation of the intimacy and extent of the endosteal contact with the reamer and final implant, which are fundamental in preventing subsidence (Fig. 5). After reaming, the trial implant is placed and the hip is reduced followed by provocative stability testing. Since this is not a modular implant, it is imperative to check the stability as changing implant length and anteversion is not as easy as it is with a modular implant. Most modern monoblock revision stems have excellent reproducibility between the reamer, the trial, and the final implant seating within the bone. Once
optimal stability is achieved, the final prosthesis is placed. After the implant is placed and the hip is reduced adequately, the femoral bone can be reconstructed around the implant and reduced with cerclage cables. The final placement of the implant should match the planned goals of the preoperative template (Fig. 6). 5. Discussion Periprosthetic femur fracture is a significant complication following total hip arthroplasty. A number of studies and metaanalyses have been done in order to identify risk factors that predispose patients to periprosthetic fracture.3e6 One of the most commonly cited risk factors is cementless femoral prostheses. Abdel et al. found an odds ratio of 13.5 when comparing uncemented to cemented fixation.3 Similarly, Thien et al. found a relative risk of 6.76 when comparing 437,629 hips using the Nordic
Fig. 5. C-arm use during reaming in order to visualize canal fit, positioning, and trajectory during the reaming process.
Please cite this article as: Menken LG, Rodriguez JA, Femoral revision for periprosthetic fracture in total hip arthroplasty, Journal of Clinical Orthopaedics and Trauma, https://doi.org/10.1016/j.jcot.2019.12.003
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Fig. 6. (A) Pre-operative plan, (B) immediate post-operative, and (C) 1 year post-operative radiographs. In growth is apparent as well as fracture healing without any evidence of subsidence or distal radiolucent lines.
Arthroplasty Registry.5 Increasing age has also been often identified as a risk factor. Age greater than 65 years old has an odds ratio of 2.5 compared to patients younger than 653 and age greater than 80 has a pooled odds ratio of 4.2 compared to patients younger than 80.6 This demonstrates an increasing risk with increasing age. More and more patients are receiving cementless hip replacements, especially in the United States.27 As these patients age, we will continue to see an increasing number of periprosthetic fractures and it is very important to have a reproducible and effective treatment plan. Daniel J. Berry introduced the concept of reconstructing the bone as a scaffold loosely around the implant without anatomic reduction. He used this technique with a distal fixating modular stem in patients with Vancouver B3 fractures. In his initial case series of 8 patients, all fractures healed within 1 year of surgery along with an increase in proximal bone stock. All of these patients were able to walk, three of whom needed no support, and none of the patients had more than mild pain.10 Fixation choice for periprosthetic fracture revision has been evolving over the last 30 years. Initially, revision with long, cemented stems bypassing the fracture was the implant of choice. However, high rates of non-union coupled with mid-term loosening caused cemented stems to fall out of favor.13 Fully porous coated implants became the gold standard following cemented stems. Over time, issues became apparent with distal fixation, subsidence, and thigh pain.14 Richards et al. performed a study directly comparing outcomes of fully porous coated stems to tapered, fluted, modular stems. Patients with tapered, fluted stems had significantly higher Oxford hip score (77 vs. 69, p ¼ 0.008), satisfaction overall score (90 vs. 81, p ¼ 0.04), and WOMAC pain and stiffness scores (84 vs. 78, p ¼ 0.04; 76 vs. 68, p ¼ 0.009, respectively) than patients receiving fully porous coated implants. The patients who received TFMTS also had more extreme preoperative proximal femoral defects than patients in the fully porous coated group, while still performing better in outcome measures, and were found to have greater restoration of proximal bone stock compared to the fully porous coated group. Currently, many surgeons choose to use TFMTS for their revision cases. A number of additional studies have looked at revision hip arthroplasty using a modular, tapered stem, including some of our own studies.15e19 We have published on tapered, fluted, modular,
titanium stems at 2e5 year follow-up and 8e15 year follow-up. At a mean 10 year follow-up, we found a 98.4% mechanical survival rate, 95.6% survival rate of stem revision for any reason, and 88.5% reoperation survival rate in a cohort of 70 patients totaling 71 revision hip surgeries. Harris hip scores improved by an average of 37 points in the cohort and all patients were able to ambulate following surgery (15 with the use of a cane, 4 with use of a walker). Complications included 2.8% rate of subsidence >5 mm, 2.8% intraoperative fracture, 4.2% developed instability, 2.8% postoperative periprosthetic femur fracture, 1.4% acetabular loosening with cup revision, and 1.4% stem fracture. In these hips, 75% showed definite (68%) or possible reconstitution of proximal bone stock while only 25% displayed femoral stress shielding. Only a small subset of these patients were revised for periprosthetic fracture, however the stem itself shows good results with revision surgery. Some studies have been done looking at the performance of tapered, modular, fluted titanium stems in the setting of periprosthetic fracture specifically. Mulay et al. reviewed their experience in a cohort of 22 patients (Link MP, Hamburg, Germany).20 In their cohort, they had 91% union rate of the fracture and an average o et al. also looked at periHarris Hip Score of 69. Da Assunça prosthetic fracture revision with a different TFMTS (Stryker Restoration, Kalamazoo, MI).13 In their cohort of 27 patients, all fractures went on to union. Patients had an average Oxford Hip Score of 35 and they found that lower Oxford Hip scores were associated with a higher American Society of Anaesthesia score. Three patients needed revision surgery, 1 for periprosthetic infection, 1 for a second periprosthetic fracture, and 1 for recurrent dislocations. Three other patients needed closed reduction of a single dislocation. Both studies showed good fracture healing and function following revision using a distally fixed modular stem. Diaz-Dilernia et al. showed modular, distally fixed stems to be superior to impaction bone grafting (IBG) technique in treatment of Vancouver B3 periprosthetic fractures.21 They found a significant association between surgical technique and complication rate with IBG having and odds ratio of 4.77 for IBG compared to modular stems. Modular stems also come with their own unique problems, however, as there have been some reported failures at the modular junction, corrosion at the modular junction, and increased cost of the implant.22e24 For these reasons, we have been using monoblock
Please cite this article as: Menken LG, Rodriguez JA, Femoral revision for periprosthetic fracture in total hip arthroplasty, Journal of Clinical Orthopaedics and Trauma, https://doi.org/10.1016/j.jcot.2019.12.003
L.G. Menken, J.A. Rodriguez / Journal of Clinical Orthopaedics and Trauma xxx (xxxx) xxx
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Fig. 7. Vancouver B3 periprosthetic fracture reconstructed with a monoblock, tapered, splined stem. There is evidence of stem subsidence measuring 1 cm at 1 year follow-up.
stems to remove the modular junction and problems associated with it while lowering costs. Monoblock stems have had good outcomes in revision surgery as well, although to our knowledge no study has yet been published on its function compared to modular stems in periprosthetic fractures specifically.24,25 Hellman at all reviewed their outcomes of revision surgery with a monoblock tapered stem (Zimmer Biomet Wagner SL, Warsaw, IN). In their cohort of 67 patients with 68 hips, 8 patients developed periprosthetic joint infections (5 of whom were revised for infection, and 6 were morbidly obese), 5 patients had dislocations (2 rerevisions), 2 patients had periprosthetic fractures, 2 patients had aseptic loosening of the stem requiring revision, 1 patient developed trunnionosis, and there were 2 patients with subsidence >1 cm. Bony ingrowth was seen in all but 4 patients in the cohort. Harris hip scores improved from a mean of 37.4 pre-operatively to 64.6 post-operatively. The Kaplan-Meier survival analysis showed an aseptic femoral stem revision estimated survival of 95.5%. Huang et al. also showed that monoblock stems, just like modular stems, promote bone formation in the proximal femur. In their study comparing 139 revision THAs with a modular stem with 114 consecutive revision THAs with a monoblock stem they found that the monoblock stems had greater osseous restoration (p ¼ 0.009) and less stress-shielding (p < 0.001) than their modular counterparts. Preliminary data in our practice has shown promising, albeit, very short term results. Since July 2016, we retrospectively reviewed 11 hips in 10 patients that had been reconstructed using a monoblock tapered, fluted, titanium stem (Alteon Monobloc Revision Stem Exactech, Inc., Gainesville, FL) following a periprosthetic fracture, after approval from our institutional IRB. Six of the 10 patients were male with an average age of 63.0 ± 12.1 (48.5e87.1) at the time of revision. All patients were diagnosed with either a Vancouver B2 (8) or B3 (3) periprosthetic fracture. At an average follow-up time of 9.3 ± 5.8 (5.2e22.2) months, one patient needed a reoperation with no other complications to report. The patient needed an irrigation and debridement for a superficial wound infection. On radiographic analysis, all patients show evidence of callus formation with fracture healing. All 11 stems show evidence of osseointegration distally.26 One patient with a Vancouver B3 fracture, and Paprosky 3B bone loss has evidence of subsidence >5 mm. This patient has fracture healing with evident osseointegration; the patient is functioning well clinically at most recent follow-up (Fig. 7). There is evidence of osseous restoration of the proximal femur in 3 of the 11 hips.
Although the use of monoblock stems in the setting of periprosthetic fractures is an emerging technique, it has shown promising results in revision surgery. More long-term studies comparing monoblock stems to modular distally fixed stems and extensively porous coated stems will be needed in order to definitively show that it is a safe and reproducible technique in periprosthetic fracture fixation. 6. Conclusion Periprosthetic fracture remains a morbid condition that is problematic for both patients and surgeons alike. It is important to develop a reproducible technique for fracture fixation in order to allow the patient to heal and to return to their pre-operative functional level. In our practice, we use a tapered, fluted, splined, monoblock stem for periprosthetic fracture revision. Pre-operative templating is very important in order to have a set plan for reconstruction in terms of leg length and offset. Fracture fixation by reducing fracture fragments around the implanted prosthesis provides good outcomes without the need for anatomic reduction of the fracture. Funding This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. Declaration of competing interest Luke G. Menken: None. Jose A. Rodriguez: AAHKS (board or committee member); Clinical Orthopaedics and Related Research (editorial or governing board); HSS Journal (editorial or governing board); ConforMIS (IP royalties, paid consultant); Eastern Orthopaedic Association (national committee); Exactech, Inc. (IP royalties, paid consultant, research support); Journal of Arthroplasty (editorial or governing board); Medacta (IP royalties, paid consultant); Smith & Nephew (paid consultant, research support); SWORD Health. References 1. Bozic KJ, et al. The epidemiology of revision total hip arthroplasty in the United States. J Bone Jt Surg Ser A. 2009;91:128e133. 2. Lindahl H, Malchau H, Herberts P, Garellick G. Periprosthetic femoral fractures: classification and demographics of 1049 periprosthetic femoral fractures from
Please cite this article as: Menken LG, Rodriguez JA, Femoral revision for periprosthetic fracture in total hip arthroplasty, Journal of Clinical Orthopaedics and Trauma, https://doi.org/10.1016/j.jcot.2019.12.003
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7. 8.
9.
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12. 13.
14.
the Swedish National Hip Arthroplasty Register. J Arthroplast. 2005;20: 857e865. Abdel MP, Watts CD, Houdek MT, Lewallen DG, Berry DJ. Epidemiology of periprosthetic fracture of the femur in 32 644 primary total hip arthroplasties. Bone Joint J. 2016;98-B:461e467. Sidler-Maier CC, Waddell JP. Incidence and predisposing factors of periprosthetic proximal femoral fractures: a literature review. Int Orthop. 2015;39: 1673e1682. Thien TM, et al. Periprosthetic femoral fracture within two years after total hip replacement: analysis of 437,629 operations in the nordic arthroplasty register association database. J Bone Jt Surg Am. 2014;96:e167. Zhu Y, et al. Risk factors for the periprosthetic fracture after total hip arthroplasty: a systematic review and meta-analysis. Scand J Surg. 2015;104: 139e145. Bhattacharyya T, Chang D, Meigs JB, Estok DM, Malchau H. Mortality after periprosthetic fracture of the femur. J Bone Jt Surg Ser A. 2007;89 A:2658e2662. Young SW, Walker CG, Pitto RP. Functional outcome of femoral peri prosthetic fracture and revision hip arthroplasty: a matched-pair study from the New Zealand Registry. Acta Orthop. 2008;79:483e488. Naqvi GA, Baig SA, Awan. , N. Interobserver and intraobserver reliability and validity of the vancouver classification system of periprosthetic femoral fractures after hip arthroplasty. J Arthroplast. 2012;27:1047e1050. Berry DJ. Treatment of Vancouver B3 periprosthetic femur fractures with a fluted tapered stem. Clin Orthop Relat Res. 2003:224e231. https://doi.org/ 10.1097/01.blo.0000096821.67494.f6. Rodriguez JA, et al. Preoperative planning and surgical technique in the management of periprosthetic femoral fractures using a tapered modular fluted prosthesis with distal fixation. Oper Tech Orthop. 2009;19:137e142. Parvizi J, et al. Treatment protocol for proximal femoral periprosthetic fractures. J Bone Jt Surg Ser A. 2004;86:8e16. Da Assunç~ ao RE, et al. Revision arthroplasty for periprosthetic femoral fracture using an uncemented modular tapered conical stem. Bone Jt J. 2015;97-B: 1031e1037. Richards CJ, Duncan CP, Masri BA, Garbuz DS. Femoral revision hip arthroplasty: a comparison of two stem designs. Clin Orthop Relat Res. 2010;468: 491e496.
15. Rodriguez JA, Fada R, Murphy SB, Rasquinha VJ, Ranawat CS. Two-year to fiveyear follow-up of femoral defects in femoral revision treated with the link MP modular stem. J Arthroplast. 2009;24:751e758. 16. Rodriguez JA, et al. Reproducible fixation with a tapered, fluted, modular, titanium stem in revision hip arthroplasty at 8-15 years follow-up. J Arthroplast. 2014;29:214e218. 17. Derogatis MJ, Wintermeyer E, Sperring TR, Issack PS. Modular fluted titanium stems in revision hip arthroplasty. J Bone Jt Surg. 2019;101-A:745e754. 18. Abdel MP, Cottino U, Mabry TM. Management of periprosthetic femoral fractures following total hip arthroplasty: a review. Int Orthop. 2015;39: 2005e2010. 19. Tsiridis E, Haddad FS, Gie GA. The management of periprosthetic femoral fractures around hip replacements. Injury. 2003;34:95e105. 20. Mulay S, Hassan T, Birtwistle S, Power R. Management of types B2 and B3 femoral periprosthetic fractures by a tapered, fluted, and distally fixed stem. J Arthroplast. 2005;20:751e756. 21. Diaz-Dilernia F, et al. Impaction bone grafting or uncemented modular stems for the treatment of type B3 periprosthetic femoral fractures? A complication rate analysis. J Arthroplast. 2019;34. 22. Efe T, Schmitt J. Analyses of prosthesis stem failures in noncemented modular hip revision prostheses. J Arthroplast. 2011;26:665. e7-665.e12. 23. Lakstein D, et al. Fracture of cementless femoral stems at the mid-stem junction in modular revision hip arthroplasty systems. J Bone Jt Surg Ser A. 2011;93: 57e65. 24. Hellman MD, Kearns SM, Bohl DD, Haughom BD, Levine BR. Revision total hip arthroplasty with a monoblock splined tapered grit-blasted titanium stem. J Arthroplast. 2017;32:3698e3703. 25. Huang Y, et al. Femoral bone remodeling in revision total hip arthroplasty with use of modular compared with monoblock tapered fluted titanium stems: the role of stem length and stiffness. J Bone Jt Surg. 2019;101-A:531e538. 26. Rodriguez JA, et al. Patterns of osseointegration and remodeling in femoral revision with bone loss using modular, tapered, fluted, titanium stems. J Arthroplast. 2011;26:1409e1417. e1. 27. Lehil MS, Bozic KJ. Trends in Total Hip Arthroplasty Implant Utilization in the United States. J. Arthroplast. 2014;29:1915e1918. https://doi.org/10.1016/ j.arth.2014.05.017.
Please cite this article as: Menken LG, Rodriguez JA, Femoral revision for periprosthetic fracture in total hip arthroplasty, Journal of Clinical Orthopaedics and Trauma, https://doi.org/10.1016/j.jcot.2019.12.003
Contents lists available at ScienceDirect
Journal of Clinical Orthopaedics and Trauma journal homepage: www.elsevier.com/locate/jcot
Femoral revision for periprosthetic fracture in total hip arthroplasty Luke G. Menken*, Jose A. Rodriguez Hospital for Special Surgery, 535 E 70th St, 10021, New York, NY, USA
a r t i c l e i n f o
a b s t r a c t
Article history: Received 22 November 2019 Accepted 11 December 2019 Available online xxx
Periprosthetic fracture can create significant morbidity in the arthroplasty population. Patients with periprosthetic fracture have been shown to have worse outcomes and higher mortality than patients undergoing elective revision THA. In this review, we will focus on Vancouver B2 and B3 fractures. Both of these fracture types are associated with a loose primary prosthesis and warrant revision surgery. There are many different options for fixation choice of the femoral prosthesis, and preference has been evolving over the last 30 years. Currently, we use monoblock, tapered, fluted, titanium stems for all periprosthetic fracture revision surgeries. © 2019
Keywords: Revision hip surgery Periprosthetic femur fracture Total hip arthroplasty
1. Introduction
2. Classification
Total hip arthroplasty (THA) is a very successful procedure with expanding indications. As the prevalence of total hip replacements increases, the incidence of short-term and long-term complications is set to increase as well.1 Arthroplasty indications are expanding and they are currently being performed in both older patients with poor bone quality and young patients with high activity demands.2 One complication that has been highly studied and is seen in both patient populations is post-operative periprosthetic fractures. The reported incidence varies between 0.07 and 18%.2e6 These fractures can occur from low energy trauma, stress risers, or even missed intraoperative fractures that propagate post-operatively. Periprosthetic fracture can create significant morbidity in the arthroplasty population. Many factors can affect the risk of sustaining a periprosthetic fracture. Some commonly reported factors increasing risk include age, gender, BMI, component fixation, stem design, surgical approach, primary diagnosis (i.e., avascular necrosis, rheumatoid arthritis), and medical comorbidities that can result in decreased bone density.3e6 Patients with periprosthetic fracture have been shown to have worse outcomes and higher mortality than patients undergoing elective revision THA.7,8 It is essential to develop meticulous technique to promote fracture healing and stable implant integration in order to allow these patients to return to their pre-injury functional level.
Many classification systems have been proposed to describe periprosthetic fractures. However, the most commonly used classification system is the Vancouver classification. The Vancouver classification is a validated system that both describes the fracture pattern and suggests a treatment algorithm for each fracture type.9 The classification is demonstrated in Table 1. In this review, we will focus on Vancouver B2 and B3 fractures. Both of these fracture types are associated with loose primary prosthesis and warrant revision surgery, and these are treated similarly in our practice. Many different reconstructive options are available for surgeons to choose from. Some stem designs include long, cemented stems, fully porous coated stems, tapered, splined, modular or monoblock stems, and proximal femoral replacement prostheses. Currently in our practice, we use tapered, splined monoblock stems for all periprosthetic fracture revisions. We have followed concepts established by Berry of seeking to rest the implant on distal intact bone and reconstructing the proximal femoral fragments around the implant.10
* Corresponding author. E-mail addresses: [email protected] (L.G. Menken), [email protected] (J.A. Rodriguez).
3. Pre-op planning11 The first step in achieving fracture fixation and return to function is a sound, reproducible pre-operative template. It is particularly important in periprosthetic fracture revision to have a concrete plan for fixation because the tissue trauma distorts the typical anatomy. In order to properly template, the surgeon will need to acquire radiographs of the hip and femur in both AP and lateral views. An
https://doi.org/10.1016/j.jcot.2019.12.003 0976-5662/© 2019
Please cite this article as: Menken LG, Rodriguez JA, Femoral revision for periprosthetic fracture in total hip arthroplasty, Journal of Clinical Orthopaedics and Trauma, https://doi.org/10.1016/j.jcot.2019.12.003
2
L.G. Menken, J.A. Rodriguez / Journal of Clinical Orthopaedics and Trauma xxx (xxxx) xxx
Table 1 Vancouver classification of post-operative periprosthetic femur fractures. Classification A B
C
AG AL B1 B2 B3
Fracture Location
Treatment
Greater trochanter fracture Lesser trochanter fracture Fracture around the prosthesis, stem well fixed Fracture around the prosthesis, stem is loose Fracture around the prosthesis, loose stem and poor proximal bone stock Fracture distal to tip of stem
Non-operative or ORIF Non-operative or ORIF ORIF Revision arthroplasty Revision arthroplasty ORIF
assessment of the existing bone stock should be done at this time in order to determine the best reconstructive option. The surgeon will have to determine the proper center of rotation of the femoral head and set a goal for leg length. Working distally from the desired center of rotation, the surgeon must identify the remaining bone that can provide axial and rotational support for the proposed implant and choose the appropriate size and length to achieve the center of rotation and offset goals. Information for optimal sizing of the stem can be sought on the contralateral side where normal or comparable anatomy is demonstrated. Once the surgeon has used the contralateral side for sizing, the operative side should be assessed. First, the surgeon should identify where the stem was sitting in the femur before the fracture. This can usually be seen in both cemented and uncemented stems status post periprosthetic fracture. Based on this point, the subsidence distance is measured from the distal tip of the prosthesis to the former distal point of the implant position. This distance is then added to the current center of rotation along a superomedial vector (Fig. 1). The distance is marked on the x-ray and will be used in order to determine the proper length of the templated implant. Next, the surgeon should identify the most proximal, identifiable part of the distal fracture fragment. This will be used during the operation as a reference for reamer positioning, in order to achieve the desired leg length. The distance between this bony landmark and the þ0 femoral head mark on template in the desired position within the femur should be measured. During the operation, this distance can be replicated to achieve the proper depth of reaming so that the prosthesis sits in the correct position upon implantation (Fig. 2). If pre-fracture x-rays are available, these can
Fig. 2. Measurement of proximal most portion of the distal fracture fragment at the medial cortex to the planned center of rotation on pre-op x-ray and during the operation.
also be used in order to assess proper stem sizing and positioning on the operative side. The implant sizing and positioning is of paramount importance and should be carefully templated. The tapered, splined, monoblock stem does not gain fixation by 3-point contact but by its placement in the conical, reamed bone bed. There should be a tight press fit of the splines along with 2e4 cm of diaphyseal bone supporting the implant distal to the end of the fracture.12,13 This type of implant gains it stability due to the conical shape of prosthesis, preventing subsidence, and due to the splines, which prevent axial rotation. 4. Surgical technique
Fig. 1. (A) Periprosthetic fracture with clear outline of former implant position (blue arrow). (B) Preoperative plan including measurement of subsidence and adding it to the center of rotation in a superomedial direction for final implant proximal positioning.
There are a number of different options in terms of surgical approach. Most often, the surgery is done through the posterolateral approach; however, the direct anterior approach and anterolateral approach are also options. Typically, we will choose the approach that was used previously in the primary surgery. That way, the capsule is not violated anteriorly and posteriorly, thus maintaining capsular support so as to not detract from the stability of the final construct. Once the femur is exposed, the fracture fragments are used like an osteotomy and any cement or debris can be cleared from the medullary canal. All soft tissue attachments to the fracture fragments should be maintained during the approach so that none of the vascular supply is compromised which will aid later on in fracture healing.10 Proceeding to the femoral preparation, the proximal piece of the distal diaphyseal fragment that was used for templating should first be identified. This will be used to mark the reamer with the predetermined distance that was templated prior to surgery (Fig. 3). A prophylactic cable should be placed distal to the fracture so that there is no fracture propagation during the reaming process (Fig. 4). Once the reamer is marked, the surgeon should double check the depth of the reamer by placing it along the thigh to estimate final placement.
Please cite this article as: Menken LG, Rodriguez JA, Femoral revision for periprosthetic fracture in total hip arthroplasty, Journal of Clinical Orthopaedics and Trauma, https://doi.org/10.1016/j.jcot.2019.12.003
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Fig. 3. Proximal portion of distal fracture fragment identified and used to measure the templated distance and mark the reamer so that the conically reamed bone bed is at the appropriate depth within the canal.
Fig. 4. Adding a cable distal to the fracture in order to prevent fracture propagation during the reaming process. The distal most aspect of the fracture fragment is seen at the blue arrow.
We perform reaming by hand using fluoroscopy as guidance with the thigh resting on the C-arm, or more commonly mini C-arm detector. The mini C-arm is used for a few reasons, it allows approximation of the templated positioning of the final implant, it allows maneuvering around any femoral defects, and it prevents reaming in an overly anterior direction, which could potentially violate the anterior cortex. Finally, the mini C-arm allows for confirmation of the intimacy and extent of the endosteal contact with the reamer and final implant, which are fundamental in preventing subsidence (Fig. 5). After reaming, the trial implant is placed and the hip is reduced followed by provocative stability testing. Since this is not a modular implant, it is imperative to check the stability as changing implant length and anteversion is not as easy as it is with a modular implant. Most modern monoblock revision stems have excellent reproducibility between the reamer, the trial, and the final implant seating within the bone. Once
optimal stability is achieved, the final prosthesis is placed. After the implant is placed and the hip is reduced adequately, the femoral bone can be reconstructed around the implant and reduced with cerclage cables. The final placement of the implant should match the planned goals of the preoperative template (Fig. 6). 5. Discussion Periprosthetic femur fracture is a significant complication following total hip arthroplasty. A number of studies and metaanalyses have been done in order to identify risk factors that predispose patients to periprosthetic fracture.3e6 One of the most commonly cited risk factors is cementless femoral prostheses. Abdel et al. found an odds ratio of 13.5 when comparing uncemented to cemented fixation.3 Similarly, Thien et al. found a relative risk of 6.76 when comparing 437,629 hips using the Nordic
Fig. 5. C-arm use during reaming in order to visualize canal fit, positioning, and trajectory during the reaming process.
Please cite this article as: Menken LG, Rodriguez JA, Femoral revision for periprosthetic fracture in total hip arthroplasty, Journal of Clinical Orthopaedics and Trauma, https://doi.org/10.1016/j.jcot.2019.12.003
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Fig. 6. (A) Pre-operative plan, (B) immediate post-operative, and (C) 1 year post-operative radiographs. In growth is apparent as well as fracture healing without any evidence of subsidence or distal radiolucent lines.
Arthroplasty Registry.5 Increasing age has also been often identified as a risk factor. Age greater than 65 years old has an odds ratio of 2.5 compared to patients younger than 653 and age greater than 80 has a pooled odds ratio of 4.2 compared to patients younger than 80.6 This demonstrates an increasing risk with increasing age. More and more patients are receiving cementless hip replacements, especially in the United States.27 As these patients age, we will continue to see an increasing number of periprosthetic fractures and it is very important to have a reproducible and effective treatment plan. Daniel J. Berry introduced the concept of reconstructing the bone as a scaffold loosely around the implant without anatomic reduction. He used this technique with a distal fixating modular stem in patients with Vancouver B3 fractures. In his initial case series of 8 patients, all fractures healed within 1 year of surgery along with an increase in proximal bone stock. All of these patients were able to walk, three of whom needed no support, and none of the patients had more than mild pain.10 Fixation choice for periprosthetic fracture revision has been evolving over the last 30 years. Initially, revision with long, cemented stems bypassing the fracture was the implant of choice. However, high rates of non-union coupled with mid-term loosening caused cemented stems to fall out of favor.13 Fully porous coated implants became the gold standard following cemented stems. Over time, issues became apparent with distal fixation, subsidence, and thigh pain.14 Richards et al. performed a study directly comparing outcomes of fully porous coated stems to tapered, fluted, modular stems. Patients with tapered, fluted stems had significantly higher Oxford hip score (77 vs. 69, p ¼ 0.008), satisfaction overall score (90 vs. 81, p ¼ 0.04), and WOMAC pain and stiffness scores (84 vs. 78, p ¼ 0.04; 76 vs. 68, p ¼ 0.009, respectively) than patients receiving fully porous coated implants. The patients who received TFMTS also had more extreme preoperative proximal femoral defects than patients in the fully porous coated group, while still performing better in outcome measures, and were found to have greater restoration of proximal bone stock compared to the fully porous coated group. Currently, many surgeons choose to use TFMTS for their revision cases. A number of additional studies have looked at revision hip arthroplasty using a modular, tapered stem, including some of our own studies.15e19 We have published on tapered, fluted, modular,
titanium stems at 2e5 year follow-up and 8e15 year follow-up. At a mean 10 year follow-up, we found a 98.4% mechanical survival rate, 95.6% survival rate of stem revision for any reason, and 88.5% reoperation survival rate in a cohort of 70 patients totaling 71 revision hip surgeries. Harris hip scores improved by an average of 37 points in the cohort and all patients were able to ambulate following surgery (15 with the use of a cane, 4 with use of a walker). Complications included 2.8% rate of subsidence >5 mm, 2.8% intraoperative fracture, 4.2% developed instability, 2.8% postoperative periprosthetic femur fracture, 1.4% acetabular loosening with cup revision, and 1.4% stem fracture. In these hips, 75% showed definite (68%) or possible reconstitution of proximal bone stock while only 25% displayed femoral stress shielding. Only a small subset of these patients were revised for periprosthetic fracture, however the stem itself shows good results with revision surgery. Some studies have been done looking at the performance of tapered, modular, fluted titanium stems in the setting of periprosthetic fracture specifically. Mulay et al. reviewed their experience in a cohort of 22 patients (Link MP, Hamburg, Germany).20 In their cohort, they had 91% union rate of the fracture and an average o et al. also looked at periHarris Hip Score of 69. Da Assunça prosthetic fracture revision with a different TFMTS (Stryker Restoration, Kalamazoo, MI).13 In their cohort of 27 patients, all fractures went on to union. Patients had an average Oxford Hip Score of 35 and they found that lower Oxford Hip scores were associated with a higher American Society of Anaesthesia score. Three patients needed revision surgery, 1 for periprosthetic infection, 1 for a second periprosthetic fracture, and 1 for recurrent dislocations. Three other patients needed closed reduction of a single dislocation. Both studies showed good fracture healing and function following revision using a distally fixed modular stem. Diaz-Dilernia et al. showed modular, distally fixed stems to be superior to impaction bone grafting (IBG) technique in treatment of Vancouver B3 periprosthetic fractures.21 They found a significant association between surgical technique and complication rate with IBG having and odds ratio of 4.77 for IBG compared to modular stems. Modular stems also come with their own unique problems, however, as there have been some reported failures at the modular junction, corrosion at the modular junction, and increased cost of the implant.22e24 For these reasons, we have been using monoblock
Please cite this article as: Menken LG, Rodriguez JA, Femoral revision for periprosthetic fracture in total hip arthroplasty, Journal of Clinical Orthopaedics and Trauma, https://doi.org/10.1016/j.jcot.2019.12.003
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Fig. 7. Vancouver B3 periprosthetic fracture reconstructed with a monoblock, tapered, splined stem. There is evidence of stem subsidence measuring 1 cm at 1 year follow-up.
stems to remove the modular junction and problems associated with it while lowering costs. Monoblock stems have had good outcomes in revision surgery as well, although to our knowledge no study has yet been published on its function compared to modular stems in periprosthetic fractures specifically.24,25 Hellman at all reviewed their outcomes of revision surgery with a monoblock tapered stem (Zimmer Biomet Wagner SL, Warsaw, IN). In their cohort of 67 patients with 68 hips, 8 patients developed periprosthetic joint infections (5 of whom were revised for infection, and 6 were morbidly obese), 5 patients had dislocations (2 rerevisions), 2 patients had periprosthetic fractures, 2 patients had aseptic loosening of the stem requiring revision, 1 patient developed trunnionosis, and there were 2 patients with subsidence >1 cm. Bony ingrowth was seen in all but 4 patients in the cohort. Harris hip scores improved from a mean of 37.4 pre-operatively to 64.6 post-operatively. The Kaplan-Meier survival analysis showed an aseptic femoral stem revision estimated survival of 95.5%. Huang et al. also showed that monoblock stems, just like modular stems, promote bone formation in the proximal femur. In their study comparing 139 revision THAs with a modular stem with 114 consecutive revision THAs with a monoblock stem they found that the monoblock stems had greater osseous restoration (p ¼ 0.009) and less stress-shielding (p < 0.001) than their modular counterparts. Preliminary data in our practice has shown promising, albeit, very short term results. Since July 2016, we retrospectively reviewed 11 hips in 10 patients that had been reconstructed using a monoblock tapered, fluted, titanium stem (Alteon Monobloc Revision Stem Exactech, Inc., Gainesville, FL) following a periprosthetic fracture, after approval from our institutional IRB. Six of the 10 patients were male with an average age of 63.0 ± 12.1 (48.5e87.1) at the time of revision. All patients were diagnosed with either a Vancouver B2 (8) or B3 (3) periprosthetic fracture. At an average follow-up time of 9.3 ± 5.8 (5.2e22.2) months, one patient needed a reoperation with no other complications to report. The patient needed an irrigation and debridement for a superficial wound infection. On radiographic analysis, all patients show evidence of callus formation with fracture healing. All 11 stems show evidence of osseointegration distally.26 One patient with a Vancouver B3 fracture, and Paprosky 3B bone loss has evidence of subsidence >5 mm. This patient has fracture healing with evident osseointegration; the patient is functioning well clinically at most recent follow-up (Fig. 7). There is evidence of osseous restoration of the proximal femur in 3 of the 11 hips.
Although the use of monoblock stems in the setting of periprosthetic fractures is an emerging technique, it has shown promising results in revision surgery. More long-term studies comparing monoblock stems to modular distally fixed stems and extensively porous coated stems will be needed in order to definitively show that it is a safe and reproducible technique in periprosthetic fracture fixation. 6. Conclusion Periprosthetic fracture remains a morbid condition that is problematic for both patients and surgeons alike. It is important to develop a reproducible technique for fracture fixation in order to allow the patient to heal and to return to their pre-operative functional level. In our practice, we use a tapered, fluted, splined, monoblock stem for periprosthetic fracture revision. Pre-operative templating is very important in order to have a set plan for reconstruction in terms of leg length and offset. Fracture fixation by reducing fracture fragments around the implanted prosthesis provides good outcomes without the need for anatomic reduction of the fracture. Funding This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. Declaration of competing interest Luke G. Menken: None. Jose A. Rodriguez: AAHKS (board or committee member); Clinical Orthopaedics and Related Research (editorial or governing board); HSS Journal (editorial or governing board); ConforMIS (IP royalties, paid consultant); Eastern Orthopaedic Association (national committee); Exactech, Inc. (IP royalties, paid consultant, research support); Journal of Arthroplasty (editorial or governing board); Medacta (IP royalties, paid consultant); Smith & Nephew (paid consultant, research support); SWORD Health. References 1. Bozic KJ, et al. The epidemiology of revision total hip arthroplasty in the United States. J Bone Jt Surg Ser A. 2009;91:128e133. 2. Lindahl H, Malchau H, Herberts P, Garellick G. Periprosthetic femoral fractures: classification and demographics of 1049 periprosthetic femoral fractures from
Please cite this article as: Menken LG, Rodriguez JA, Femoral revision for periprosthetic fracture in total hip arthroplasty, Journal of Clinical Orthopaedics and Trauma, https://doi.org/10.1016/j.jcot.2019.12.003
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15. Rodriguez JA, Fada R, Murphy SB, Rasquinha VJ, Ranawat CS. Two-year to fiveyear follow-up of femoral defects in femoral revision treated with the link MP modular stem. J Arthroplast. 2009;24:751e758. 16. Rodriguez JA, et al. Reproducible fixation with a tapered, fluted, modular, titanium stem in revision hip arthroplasty at 8-15 years follow-up. J Arthroplast. 2014;29:214e218. 17. Derogatis MJ, Wintermeyer E, Sperring TR, Issack PS. Modular fluted titanium stems in revision hip arthroplasty. J Bone Jt Surg. 2019;101-A:745e754. 18. Abdel MP, Cottino U, Mabry TM. Management of periprosthetic femoral fractures following total hip arthroplasty: a review. Int Orthop. 2015;39: 2005e2010. 19. Tsiridis E, Haddad FS, Gie GA. The management of periprosthetic femoral fractures around hip replacements. Injury. 2003;34:95e105. 20. Mulay S, Hassan T, Birtwistle S, Power R. Management of types B2 and B3 femoral periprosthetic fractures by a tapered, fluted, and distally fixed stem. J Arthroplast. 2005;20:751e756. 21. Diaz-Dilernia F, et al. Impaction bone grafting or uncemented modular stems for the treatment of type B3 periprosthetic femoral fractures? A complication rate analysis. J Arthroplast. 2019;34. 22. Efe T, Schmitt J. Analyses of prosthesis stem failures in noncemented modular hip revision prostheses. J Arthroplast. 2011;26:665. e7-665.e12. 23. Lakstein D, et al. Fracture of cementless femoral stems at the mid-stem junction in modular revision hip arthroplasty systems. J Bone Jt Surg Ser A. 2011;93: 57e65. 24. Hellman MD, Kearns SM, Bohl DD, Haughom BD, Levine BR. Revision total hip arthroplasty with a monoblock splined tapered grit-blasted titanium stem. J Arthroplast. 2017;32:3698e3703. 25. Huang Y, et al. Femoral bone remodeling in revision total hip arthroplasty with use of modular compared with monoblock tapered fluted titanium stems: the role of stem length and stiffness. J Bone Jt Surg. 2019;101-A:531e538. 26. Rodriguez JA, et al. Patterns of osseointegration and remodeling in femoral revision with bone loss using modular, tapered, fluted, titanium stems. J Arthroplast. 2011;26:1409e1417. e1. 27. Lehil MS, Bozic KJ. Trends in Total Hip Arthroplasty Implant Utilization in the United States. J. Arthroplast. 2014;29:1915e1918. https://doi.org/10.1016/ j.arth.2014.05.017.
Please cite this article as: Menken LG, Rodriguez JA, Femoral revision for periprosthetic fracture in total hip arthroplasty, Journal of Clinical Orthopaedics and Trauma, https://doi.org/10.1016/j.jcot.2019.12.003