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Salvage of Failed Trochanteric Fracture Fixation Using the Revitan Curved Cementless Modular Hip Arthroplasty
The Journal of Arthroplasty Vol. 27 No. 7 2012
Salvage of Failed Trochanteric Fracture Fixation Using the Revitan Curved Cementless Modular Hip Arthroplasty Amr A.K.H. Abouelela, MD, PhD
Abstract: Failed internal fixation of an intertrochanteric or subtrochanteric fracture often leads to persistent pain and diminished function. This study evaluated 16 patients treated with Revitan curved cementless modular stem (Zimmer GmbH, Winterthur, Switzerland). At a mean follow-up period of 60 months, all patients demonstrated clinically significant pain relief and return to ambulation after salvage total hip arthroplasty. Mean Harris Hip Score improved from 17.8 to 87.7 points postoperatively. Radiographic follow-up demonstrated stable stem and bony ingrowth in 16 patients without evidence of subsidence. Eight patients had slight awareness of lateral trochanteric pain with no compromise of activities, and 1 patient had nonunion of the greater trochanter. Revitan curved cementless modular stem represents a useful treatment option in salvage total hip arthroplasty of failed pertrochanteric fixation. Keywords: trochanteric fracture, salvage, modular cementless stem, total hip arthroplasty, conversion. © 2012 Elsevier Inc. All rights reserved.
Open or closed reduction and internal fixation have been widely accepted as an effective treatment of proximal hip fractures. With contemporary surgical technique and fixation devices, most intertrochanteric and subtrochanteric fractures can be treated successfully [1,2]. Nevertheless, treatment of these fractures occasionally fails. This may be due to poor bone quality, unstable fracture reduction, or poor implant position. The reported overall failure rates with internal fixation are as follows: 3% to 12% failure in the internal fixation itself, 2% to 12% device penetration, 2% to 5% nonunion, and 5% to 11% malunion causing varus deformity [3-5]. Total hip arthroplasty (THA) is generally accepted as a successful salvage procedure for failed hip fixation. This is indicated in scenarios where there is poor remaining bone stock, substantial femoral head compromise, established nonunion, or significant limb shortening [6-10]. From the Department of Orthopedic Surgery and Traumatology, Ain Shams University Hospitals, Cairo, Egypt. Submitted February 13, 2011; accepted October 19, 2011. The Conflict of Interest statement associated with this article can be found at doi:10.1016/j.arth.2011.10.021. Reprint requests: Amr A.K.H. Abouelela, MD, PhD, Department of Orthopedic Surgery and Traumatology, Ain Shams University Hospitals, El-Khalifa El-Maamoun St. Abbassia, Cairo, Egypt. © 2012 Elsevier Inc. All rights reserved. 0883-5403/2707-0021$36.00/0 doi:10.1016/j.arth.2011.10.021
Patients with failed intertrochanteric and subtrochanteric fracture fixation have bone loss below the standard resection level for routine primary THA. Nevertheless, successful femoral component fixation could be obtained with either cemented or cementless implants [7,8,11]. Published series on cemented stems affords reported rates of deep infection, periprosthetic fracture, dislocation, early implant failure, and reoperation slightly higher than those normally seen in the osteoarthritic population undergoing primary THA [6,10,12,13]. If a cementless press-fit stem is used, a fully coated long-stem prosthesis usually is preferred to bypass the stress risers and the weak proximal bone, which is prone to fracture [7,10,11]. Nonetheless, complications often occur at points where the anterior femoral bow abuts on the tip of the stem, creating the possibility of a perforation of the cortex and either an intraoperative fracture or a late periprosthetic fracture, with resultant thigh pain. Moreover, the issues of malrotation of the proximal femoral anatomy along with soft tissue balancing also exist and are difficult to correct by a monobloc fully coated long stem especially in a malunion [14,15]. A curved modular hip system accommodates all the issues mentioned above. Modularity permits independent fitting of the diaphysis and metaphysis along with accurate adjustment of length, offset, and version. Furthermore, modularity creates a construct that will not compromise the fixation or the subsequent reconstructed anatomy [16].
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Failed Trochanteric Fracture Fixation Salvage Using Revitan Abouelela
The Revitan stem (Zimmer GmbH, Winterthur, Switzerland) is a modern, curved modular revision stem. The distal curved components of these stems have an octagonal transverse section with a taper of 2°. Additional interlocking screws can be inserted in the distal component. Previous studies with this system have yielded satisfactory results in revision THA [17,18]. To our knowledge, there is no published study analyzing the results of Revitan curved revision stems in salvage of failed hip fixation. The purpose of the present study was to evaluate the efficacy of conversion THA using the Revitan modular curved revision stem as a salvage procedure for failed fixation of intertrochanteric and subtrochanteric fractures in a study population consisting of 16 patients who were followed up for more than 5 years.
Materials and Methods Between January 2005 and January 2011, 16 patients (9 men and 7 women) were treated at our university hospital with conversion THA after failed fixation of intertrochanteric or subtrochanteric hip fracture. The mean age at the time of fracture was 64 years (range, 46-74 years). The mean interval from initial fracture fixation to conversion arthroplasty was 10.9 months (range, 5-22 months). Twelve patients had failed treatment with a dynamic hip screw for intertrochanteric fractures, and 4 patients had failed treatment with a dynamic condylar screw for subtrochanteric fractures. All fractures were evaluated using the Arbeitsgemeinschaft für Osteosynthesefragen classifica-
Table 1. Demographic Data of Patients Age Sex Male Female Interval from initial fracture fixation to conversion arthroplasty Fracture morphology Intertrochanteric Subtrochanteric Indication (failure of fixation) Nonunion with penetration of the lag screw into the acetabulum Nonunion with breakage of the side plate and the screws Malunion with lag screw cutting out Fixation used Dynamic hip screw for intertrochanteric fracture Dynamic condylar screw for subtrochanteric fracture AO (classification) A2.3 A3.3
64 y (range, 46-74 y) 9 7 10.9 mo (range, 5-22 mo) 12 4 7 6 3 12 4
12 4
AO indicates Arbeitsgemeinschaft für Osteosynthesefragen.
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tion for intertrochanteric fractures as proposed by Rüedi et al [19]. The fracture fixation failure modes in the study sample were as follows: nonunion with secondary acetabular erosion by a penetrated lag screw in 7 patients, nonunion with breakage of the side plate and screws in 6 patients, and malunion with lag screw cutting through in 3 patients. All patients underwent preoperative detailed clinical examination and evaluation for medical comorbidities. All hips were evaluated according to Harris Hip Score (HHS) [20]. Occult infection as a cause of failure was always considered, and a complete preoperative blood count with determination of erythrocytes sedimentation rate and C-reactive protein was done. Patient demographics are summarized in Table 1. Preoperative radiographs were examined carefully to determine the type of fixation device, the osseous condition, and the degree of union of the greater trochanter. The possible loss of bone in the acetabulum from device penetration was also noted.
Surgical Procedure The author, through a lateral approach, performed all procedures. After removal of the failed implant, the resected femoral head was reserved for later autografting. In all patients, the presence of infection was excluded by an intraoperative frozen biopsy of the joint capsule and Gram stain of the joint fluid. The femur was sectioned at its peritrochanteric fracture line. Osseous bars often obstructed the cylindrical anatomy of the proximal end of the distal femur. This initially required a burr hole through the osseous obstacle under image intensifier monitoring. A medullary guide wire was pushed through the distal canal down to the condylar region. Sequential flexible medullary reamers were used to prepare the distal femoral canal until the first circular bone contact of the reamers was achieved. Then the pointed bony fixation area was rasped gently until the rasping gains fixation of at least 6 cm distal to the last femoral shaft screw hole. At this stage, a 2-mm-thicker distal modular stem component was hammered in gently until fixation was achieved. This was assisted by rinsing the canal with warm saline solution to clear medullary debris and to help femoral expansion during implantation, with the additional pouring of warm saline solution on the shaft during stem impaction to help in more femoral expansion (Fig. 1). We performed intraoperative radiographs to rule out fractures and to confirm a 6-cm diaphyseal scratch fit fixation distal to the last osteosynthesis screw hole. In 7 implanted stems, the osteoporotic enlargement of the isthmus necessitated additional fixation using the distal locking screws of the stem.
1384 The Journal of Arthroplasty Vol. 27 No. 7 August 2012
Fig. 1. (A) Rinsing the medullary canal with warm saline solution before stem insertion. (B) Revitan curved cementless modular stem insertion that is 2 mm larger than the last rasp used. (C) Pouring the shaft with warm saline solution during stem impaction.
The proximal trial components and trial heads were then used to adjust the leg length, offset, and the femoral anteversion. The final proximal component and head were then implanted. The trochanteric fragments with the attached abductors were sewn together and fastened to the proximal component by number 2 Ethibond sutures (Ethicon, Somerville, NJ) in addition to cerclage wire loop passed through the 2 medial orifices in the proximal component (Fig. 2). The gap between the reattached trochanter and the distal femur was filled with spongiosa obtained from the femoral head and particles obtained from the reaming process. All of the patients' acetabuli had received replacement by uncemented Trilogy multiholed cup (Zimmer, Warsaw, Ind). Autografts from the femoral head were used in 7 hips to build up secondary acetabular defects. The friction pairing was metal (cobalt-chromium) on highly cross-linked polyethylene. Femoral head size was 32 mm in 1 hip and 36 mm in 15 hips.
All patients received antibiotics before induction of anesthesia and were continued for 5 days postoperatively, and all received postoperative thromboembolic prophylaxis with low-molecular-weight heparin until the patients were fully mobile. No routine prophylaxis for heterotopic ossification was used. The operated hip was not allowed to flex beyond 60° for the initial 5 weeks to avoid movement of the reattached trochanter. The operated limb was kept non–weight-bearing for 3 weeks followed by partial loading with 10 kg for another 3 weeks and then gradually increasing the load 10 kg/wk until full weight-bearing was achieved.
Follow-Up Examination Clinical and radiologic examinations of the patients were carried out at 3 weeks, 6 weeks, 3 months, and 6 months during the first postoperative year and thereafter every 6 months.
Fig. 2. (A) Cerclage wire loop passed through the 2 medial orifices in the final proximal component to reattach the trochanteric fragments. (B) Trochanteric fragments with attached abductors were sewn together by number 2 Ethibond sutures and fastened to the proximal component.
Failed Trochanteric Fracture Fixation Salvage Using Revitan Abouelela
The clinical outcome was evaluated by the author using the HHS combined with examination of the Trendelenburg sign and limb-length discrepancy. The radiographic evaluation consisted of a review of preoperative, postoperative, and the most recent radiographs by a senior consultant with no direct knowledge of the specific cases. The modular femoral stem implantation was assessed by observing the radiographic stabilities and the presence of a periprosthetic radiolucent line according to Engh et al [21]. The percentage of canal fill by the stem was determined using the technique of Tanzer et al [22]. The distal component fixation zone length distal to the last removed osteosynthesis screw hole was measured, and the rate of union of the trochanter was assessed. In addition, subsidence was measured using the technique of Callaghan et al [23]. The reference landmark used to assess subsidence was the distance from the top of the distal component (modular junction) to the most proximal portion of the lesser trochanter. Radiologic signs of stem loosening were the presence of more than 5 mm of progressive subsidence, breakage of interlocking screws, pedestal formation, or a continuous radiolucent line around the stem. The cup osseointegration was evaluated according to the criteria proposed by Moore et al [24]. In addition, the evidence of acetabular loosening was evaluated by the criteria of Massin et al [25] for migration and the zone criteria of DeLee and Charnley [26] for radiolucent lines.
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Results The mean duration of surgery was 170 minutes (range, 140-240 minutes), and the mean estimated blood loss was 1068 mL (range, 500-1400 mL). The mean duration of postoperative follow-up for these patients was 60 months (range, 40-72 months). In the clinical assessment, all patients reported remarkable pain relief and return to ambulation after the conversion to THA. Eight patients had no pain, and 8 had slight awareness of lateral trochanteric lowgrade pain with no compromise of activities. Eight patients ambulated unassisted, 6 used a cane occasionally, and 2 used a cane most of the time. The mean HHS increased from 17.8 points (range, 0-51.2 points) preoperatively to 87.7 points (range, 71.5-100 points) at the last follow-up. A positive Trendelenburg sign was seen in all patients up to 6 months postoperatively. This sign progressively diminished until all patients had a negative Trendelenburg sign at 24 months postoperative. Restoration of leg length equality to within 10 mm was accomplished in all patients. Radiologic assessment of all 16 acetabular cups revealed apparent bone ingrowth, with neither migration nor rotation in any of them. The distal modular component of the stem filled 90% to 100% of the diaphyseal canal in the 16 hips. Cortical bone ingrowth was observed in the distal portion of the modular stem in the 16 hips (Fig. 3). There were neither signs of fibrous ingrowth, pedestal formation, locking screw breakage, nor subsidence.
Fig. 3. (A) Anteroposterior radiograph of a 66-year-old man showing nonunited subtrochanteric fracture with breakage of the side plate. (B) Anteroposterior radiograph 6 years after conversion to THA using Revitan curved cementless modular stem showing excellent osteointegration, full fracture union, and apparent cementless acetabular component bone ingrowth.
1386 The Journal of Arthroplasty Vol. 27 No. 7 August 2012 The mean distal component fixation (distal to last osteosynthesis screw hole) was 7.5 cm (range, 6-10 cm). The trochanter exhibited osseous union to the femoral diaphysis in 15 patients after 6 to 9 months. In 1 patient, trochanteric nonunion persisted, and the trochanter migrated 15 mm proximally and stopped at that level 1 year postoperatively. There was neither infection, dislocation, nor fracture in the operated hips.
Discussion The complexity of conversion THA requires a modular versatile system that can be adapted for proximal femoral bone loss, osteoporotic bone quality, altered anatomy, offset, anteversion, and limb length discrepancy. Revitan modular curved stem could deal with the vast diversity of all of the aforementioned problems. This study's key to success in obtaining primary endosteal diaphyseal fixation along with superior rotational and axial stability was the use of distal stem components 2 mm larger than the last rasp used to maximize the canal fill and fit [18,27-29]. This was aided by rinsing the canal and shaft outer surface with warm saline solution before stem implantation and during stem impaction for more diaphyseal femoral expansion. The author's own idea of insertion of 2-mm oversized distal stem and the warm saline usage during its insertion was based upon the author's anecdotal experience in cementless revision THA. This was proven to be a successful method in this study. The Revitan stem has the advantage of distal locking screws to achieve a strong initial intraoperative fixation until subsequent secondary fixation is achieved, even when the bone quality of the proximal femur was poor and bone loss was severe [30,31]. This was successfully achieved in the 7 osteoporotic hips included in this study. Mahomed et al [32] reported that distal interlocking in press-fit implant increased the torsional stability by 320% and the axial stability by 230%. In this study, no significant subsidence of the femoral implants and no mechanical loosening were seen after a mean follow-up period of 60 months. In addition, no further revision was required during the same follow-up period. These findings are compatible with other results, which emphasize the importance of the initial stability of the revision femoral components [27-31]. The radiologic findings of this study demonstrated healed trochanteric fractures in 15 patients and adequate bone ingrowth around the distal stem in 100% of femora. Therefore, osseointegration into a well-designed and successfully implanted cementless femoral stem can be achieved with good results despite the decreased osteogenic potential in these patients [33,34]. In the current study, no single dislocation occurred among the 16 conversion THAs. This is attributed to the direct lateral approach, which has been shown to have a
lower incidence of dislocation compared with other approaches [35]. Stability was also achieved by correct version placement of the proximal modular component and the restoration of adequate soft tissue tension [36-38]. Moreover, the use of large femoral heads aided in preventing dislocation [39]. Eight patients had slight awareness of pain of low grade with no compromise of activities. The pain was a lateral trochanteric pain only. This presumably was caused by mild trochanteric bursitis secondary to the lateral approach used in this study [40], retained trochanteric fixation devices, or trochanteric nonunion in 1 patient [10]. Thigh pain was not reported by any patient at the latest follow-up in this study, presumably because of stable bony ingrowth into the distal stem, which decreased micromotion at the bone implant interface that eventually prevented thigh pain [41]. Few studies have reported on the use of cementless modular femoral stems in the salvage of failed trochanteric fracture fixation. Laffosse et al [42] treated 29 elderly patients (mean age, 81.1 years) after failed internal fixation of pertrochanteric and intertrochanteric femoral fractures using the Puget prosthesis (Système PP, Tornier, Montbonnot, France). The surviving 23 patients (79%), after a mean follow-up of 20 months, reported significant pain relief and improved function. Stem subsidence was greater than 5 mm in 3 patients. Two patients had nonunion of the greater trochanter, and another 2 patients presented with early dislocation after bipolar hemiarthroplasty. Talmo and Bono [43] reported the results of 10 cementless S-ROM prosthesis (DePuy Orthopedics Inc, Warsaw, Ind) in the salvage of patients with intertrochanteric fracture nonunion. All patients reported good pain relief after a follow-up period of 30 months. The mean HHS in their study was 86. Of the 10 prosthesis, 9 had stable bone ingrowth, with 1 patient having subsidence of 10 mm and significant radiolucency. Thakur et al [44] treated 15 patients after failed internal fixation of pertrochanteric and intertrochanteric fractures with Link MP Hip Stem (Waldemar Link, Hamburg, Germany). After a follow-up period of 2.86 years (range, 2-4.5 years), all patients demonstrated significant pain relief, except in 2 patients who complained of residual trochanteric pain. The mean HHS in their study was 83. Fourteen stems had stable bone ingrowth, and 1 had stable fibrous ingrowth due to undersized implant. Two patients had greater trochanter nonunion. Our results indicated that the distal component of Revitan modular curved revision stem could bypass the weakened distorted proximal femur and could achieve stable fixation in the diaphysis with a 2-mm oversized stem than the last fitting rasp. Its proximal component helped correction of version, application of large
Failed Trochanteric Fracture Fixation Salvage Using Revitan Abouelela
modular heads, restoration of limb length, preservation of remnant proximal bone stock, and reconstruction of abductor mechanism by cerclage wiring and/or heavy sutures that are passed through its 2 medial orifices. Hence, our goals in reduction of pain and restoration of ambulation while avoiding complications such as dislocation and fracture were all met in this study series.
References 1. Kyle RF, Gustilo RB, Premer RF. Analysis of six hundred and twenty-two intertrochanteric hip fractures. J Bone Joint Surg Am 1979;61:216. 2. Kyle RF, Cabanela ME, Russell TA, et al. Fractures of the proximal part of the femur. Instr Course Lect 1995;44:227. 3. Bannister GC, Gibson AG, Akroyd CE, et al. The fixation and prognosis of trochanteric fractures. A randomized prospective controlled trial. Clin Orthop Relat Res 1990; 254:242. 4. Kyle RF, Ellis TJ, Templeman DC. Surgical treatment of intertrochanteric hip fractures with associated femoral neck fractures using a sliding hip screw. J Orthop Trauma 2005;19:1. 5. Mariani EM, Rand JA. Nonunion of intertrochanteric fractures of the femur following open reduction and internal fixation. Results of second attempts to gain union. Clin Orthop Relat Res 1987;218:81. 6. Winemaker M, Gamble P, Petruccelli D, et al. Short term outcomes of total hip arthroplasty after complications of open reduction internal fixation of hip fracture. J Arthroplasty 2006;21:682. 7. Haidukewych JG, Berry JD. Salvage of failed treatment of hip fractures. J Am Acad Orthop Surg 2005;13:101. 8. Angelini M, McKee MD, Waddell JP, et al. Salvage of failed hip fracture fixation. J Orthop Trauma 2009;23:471. 9. Zhang B, Shiu KY, Wang M. Hip arthroplasty for failed internal fixation of intertrochanteric fractures. J Arthroplasty 2004;19:329. 10. Haidukewych JG, Berry JD. Hip arthroplasty for salvage of failed treatment of intertrochanteric hip fracture. J Bone Joint Surg Am 2003;85:899. 11. Kyle RF, Cooper J. Total hip arthroplasty after failed fixation of hip fractures. Orthopedics 2006;29:783. 12. Mehlhoff T, Landon G, Tullos H. Total hip arthroplasty following failed internal fixation of hip fractures. Clin Orthop Relat Res 1991;269:32. 13. Tabsh I, Waddell JP, Morton J. Total hip arthroplasty for complications of proximal femoral fractures. J Orthop Trauma 1997;11:66. 14. Issack PS, Guerin J, Butler A, et al. Intraoperative complications of revision hip arthroplasty using a porous-coated, distally slotted, fluted femoral stem. Clin Orthop Relat Res 2004;425:173. 15. Paprosky WG, Greidanus NV, Antoniou J. Minimum 10-year-results of extensively porous-coated stems in revision hip arthroplasty. Clin Orthop Relat Res 1999; 369:230. 16. Goldstein WM, Branson JJ. Modular femoral component for conversion of previous hip surgery in total hip arthroplasty. Orthopedics 2005;28(9 Suppl):1079.
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17. Fink B, Grossmann A, Schubring S, et al. A modified transfemoral approach using modular cementless revision stems. Clin Orthop Relat Res 2007;462:105. 18. Fink B, Grossmann A, Fuerst M. Distal interlocking screws with a modular revision stem for revision total hip arthroplasty in severe bone defects. J Arthroplasty 2010; 25:759. 19. Rüedi TP, Buckley RE, Moran CG. AO principles of fracture management. 2nd expanded ed. Switzerland: AO Publishing Group; 2007. 20. Harris WH. Traumatic arthritis of the hip after dislocation and acetabular fractures: treatment by mold arthroplasty: an end result study using a new method of result evaluation. J Bone Joint Surg Am 1969;51:737. 21. Engh CA, Massin P, Suthers KE. Roentgenographic assessment of the biologic fixation of porous-surfaced femoral components. Clin Orthop Relat Res 1990;257:107. 22. Tanzer M, Chan S, Brooks CE, et al. Primary cementless total hip arthroplasty using a modular femoral component: a minimum 6-year follow-up. J Arthroplasty 2001; 16(8 Suppl):64. 23. Callaghan JJ, Salvati EA, Pellicci PM, et al. Results of revision for mechanical failure after cemented total hip replacement, 1979 to 1982. A two to five-year follow-up. J Bone Joint Surg Am 1985;67:1074. 24. Moore MS, McAuley JP, Young AM, et al. Radiographic signs of osseointegration in porous-coated acetabular components. Clin Orthop Relat Res 2006;444:176. 25. Massin P, Schmidt L, Engh CA. Evaluation of cementless acetabular component migration. An experimental study. J Arthroplasty 1989;4:245. 26. DeLee JG, Charnley J. Radiological demarcation of cemented sockets in total hip replacement. Clin Orthop Relat Res 1976;121:20. 27. Meneghini RM, Hallab NJ, Berger RA, et al. Stem diameter and rotational stability in revision total hip arthroplasty: a biomechanical analysis. J Orthop Surg Res 2006;1:1. 28. Jakubowitz E, Bitsch RG, Heisel C, et al. Primary rotational stability of cylindrical and conical revision hip stems as a function of femoral bone defects: an in vitro comparison. J Biomech 2008;41:3078. 29. Harris WH, Mulroy Jr RD, Maloney WJ, et al. Intraoperative measurement of rotational stability of femoral components of total hip arthroplasty. Clin Orthop Relat Res 1991;266:119. 30. Nourbash PS, Paprosky WG. Cementless femoral design concerns: rationale for extensive porous coating. Clin Orthop Relat Res 1998;355:189. 31. Moon KH, Kang JS, Lee SH, et al. Revision total hip arthroplasty using an extensively porous coated femoral stem. Clin Orthop Surg 2009;1:105. 32. Mahomed N, Schatzker J, Hearn T. Biomechanical analysis of a distally interlocked press-fit femoral total hip prosthesis. J Arthroplasty 1993;8:129. 33. Berend KR, Lombardi AV, Mallory TH, et al. Cementless double-tapered total hip arthroplasty in patients 75 years of age and older. J Arthroplasty 2004;19:288. 34. Sporer SM, Obar RJ, Bernini PM. Primary total hip arthroplasty using a modular proximally coated prosthesis in patients older than 70. Two to eight year results. J Arthroplasty 2004;19:197.
1388 The Journal of Arthroplasty Vol. 27 No. 7 August 2012 35. Masonis JL, Bourne RB. Surgical approach, abductor function, and total hip arthroplasty dislocation. Clin Orthop Relat Res 2002;405:46. 36. Mahoney CR, Pellicci PM. Complications in primary total hip arthroplasty: avoidance and management of dislocations. Instr Course Lect 2003;52:247. 37. Alberton GM, High WA, Morrey BF. Dislocation after revision total hip arthroplasty: an analysis of risk factors and treatment options. J Bone Joint Surg Am 2002;84: 1788. 38. Asayama I, Chamnongkich S, Simpson KJ, et al. Reconstructed hip joint position and abductor muscle strength after total hip arthroplasty. J Arthroplasty 2005;20:414. 39. Matsushita A, Nakashima Y, Jingushi S, et al. Effects of the femoral offset and the head size on the safe range of motion in total hip arthroplasty. J Arthroplasty 2009; 24:646.
40. Iorio R, Healy WL, Warren PD, et al. Lateral trochanteric pain following primary total hip arthroplasty. J Arthroplasty 2006;21:233. 41. Moreland JR, Moreno MA. Cementless femoral revision arthroplasty of the hip: minimum 5 years follow-up. Clin Orthop Relat Res 2001;393:194. 42. Laffosse JM, Molinier F, Tricoire JL, et al. Cementless modular hip arthroplasty as a salvage operation for failed internal fixation of trochanteric fractures in elderly patients. Acta Orthop Belg 2007;73:729. 43. Talmo CT, Bono JV. Treatment of intertrochanteric nonunion of proximal femur using the S-ROM prosthesis. Orthopedics 2008;31:125. 44. Thakur RR, Deshmukh AJ, Goyal A, et al. Management of failed trochanteric fracture fixation with cementless modular hip arthroplasty using a distally fixing stem. J Arthroplasty 2011;26:398.
Salvage of Failed Trochanteric Fracture Fixation Using the Revitan Curved Cementless Modular Hip Arthroplasty Amr A.K.H. Abouelela, MD, PhD
Abstract: Failed internal fixation of an intertrochanteric or subtrochanteric fracture often leads to persistent pain and diminished function. This study evaluated 16 patients treated with Revitan curved cementless modular stem (Zimmer GmbH, Winterthur, Switzerland). At a mean follow-up period of 60 months, all patients demonstrated clinically significant pain relief and return to ambulation after salvage total hip arthroplasty. Mean Harris Hip Score improved from 17.8 to 87.7 points postoperatively. Radiographic follow-up demonstrated stable stem and bony ingrowth in 16 patients without evidence of subsidence. Eight patients had slight awareness of lateral trochanteric pain with no compromise of activities, and 1 patient had nonunion of the greater trochanter. Revitan curved cementless modular stem represents a useful treatment option in salvage total hip arthroplasty of failed pertrochanteric fixation. Keywords: trochanteric fracture, salvage, modular cementless stem, total hip arthroplasty, conversion. © 2012 Elsevier Inc. All rights reserved.
Open or closed reduction and internal fixation have been widely accepted as an effective treatment of proximal hip fractures. With contemporary surgical technique and fixation devices, most intertrochanteric and subtrochanteric fractures can be treated successfully [1,2]. Nevertheless, treatment of these fractures occasionally fails. This may be due to poor bone quality, unstable fracture reduction, or poor implant position. The reported overall failure rates with internal fixation are as follows: 3% to 12% failure in the internal fixation itself, 2% to 12% device penetration, 2% to 5% nonunion, and 5% to 11% malunion causing varus deformity [3-5]. Total hip arthroplasty (THA) is generally accepted as a successful salvage procedure for failed hip fixation. This is indicated in scenarios where there is poor remaining bone stock, substantial femoral head compromise, established nonunion, or significant limb shortening [6-10]. From the Department of Orthopedic Surgery and Traumatology, Ain Shams University Hospitals, Cairo, Egypt. Submitted February 13, 2011; accepted October 19, 2011. The Conflict of Interest statement associated with this article can be found at doi:10.1016/j.arth.2011.10.021. Reprint requests: Amr A.K.H. Abouelela, MD, PhD, Department of Orthopedic Surgery and Traumatology, Ain Shams University Hospitals, El-Khalifa El-Maamoun St. Abbassia, Cairo, Egypt. © 2012 Elsevier Inc. All rights reserved. 0883-5403/2707-0021$36.00/0 doi:10.1016/j.arth.2011.10.021
Patients with failed intertrochanteric and subtrochanteric fracture fixation have bone loss below the standard resection level for routine primary THA. Nevertheless, successful femoral component fixation could be obtained with either cemented or cementless implants [7,8,11]. Published series on cemented stems affords reported rates of deep infection, periprosthetic fracture, dislocation, early implant failure, and reoperation slightly higher than those normally seen in the osteoarthritic population undergoing primary THA [6,10,12,13]. If a cementless press-fit stem is used, a fully coated long-stem prosthesis usually is preferred to bypass the stress risers and the weak proximal bone, which is prone to fracture [7,10,11]. Nonetheless, complications often occur at points where the anterior femoral bow abuts on the tip of the stem, creating the possibility of a perforation of the cortex and either an intraoperative fracture or a late periprosthetic fracture, with resultant thigh pain. Moreover, the issues of malrotation of the proximal femoral anatomy along with soft tissue balancing also exist and are difficult to correct by a monobloc fully coated long stem especially in a malunion [14,15]. A curved modular hip system accommodates all the issues mentioned above. Modularity permits independent fitting of the diaphysis and metaphysis along with accurate adjustment of length, offset, and version. Furthermore, modularity creates a construct that will not compromise the fixation or the subsequent reconstructed anatomy [16].
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Failed Trochanteric Fracture Fixation Salvage Using Revitan Abouelela
The Revitan stem (Zimmer GmbH, Winterthur, Switzerland) is a modern, curved modular revision stem. The distal curved components of these stems have an octagonal transverse section with a taper of 2°. Additional interlocking screws can be inserted in the distal component. Previous studies with this system have yielded satisfactory results in revision THA [17,18]. To our knowledge, there is no published study analyzing the results of Revitan curved revision stems in salvage of failed hip fixation. The purpose of the present study was to evaluate the efficacy of conversion THA using the Revitan modular curved revision stem as a salvage procedure for failed fixation of intertrochanteric and subtrochanteric fractures in a study population consisting of 16 patients who were followed up for more than 5 years.
Materials and Methods Between January 2005 and January 2011, 16 patients (9 men and 7 women) were treated at our university hospital with conversion THA after failed fixation of intertrochanteric or subtrochanteric hip fracture. The mean age at the time of fracture was 64 years (range, 46-74 years). The mean interval from initial fracture fixation to conversion arthroplasty was 10.9 months (range, 5-22 months). Twelve patients had failed treatment with a dynamic hip screw for intertrochanteric fractures, and 4 patients had failed treatment with a dynamic condylar screw for subtrochanteric fractures. All fractures were evaluated using the Arbeitsgemeinschaft für Osteosynthesefragen classifica-
Table 1. Demographic Data of Patients Age Sex Male Female Interval from initial fracture fixation to conversion arthroplasty Fracture morphology Intertrochanteric Subtrochanteric Indication (failure of fixation) Nonunion with penetration of the lag screw into the acetabulum Nonunion with breakage of the side plate and the screws Malunion with lag screw cutting out Fixation used Dynamic hip screw for intertrochanteric fracture Dynamic condylar screw for subtrochanteric fracture AO (classification) A2.3 A3.3
64 y (range, 46-74 y) 9 7 10.9 mo (range, 5-22 mo) 12 4 7 6 3 12 4
12 4
AO indicates Arbeitsgemeinschaft für Osteosynthesefragen.
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tion for intertrochanteric fractures as proposed by Rüedi et al [19]. The fracture fixation failure modes in the study sample were as follows: nonunion with secondary acetabular erosion by a penetrated lag screw in 7 patients, nonunion with breakage of the side plate and screws in 6 patients, and malunion with lag screw cutting through in 3 patients. All patients underwent preoperative detailed clinical examination and evaluation for medical comorbidities. All hips were evaluated according to Harris Hip Score (HHS) [20]. Occult infection as a cause of failure was always considered, and a complete preoperative blood count with determination of erythrocytes sedimentation rate and C-reactive protein was done. Patient demographics are summarized in Table 1. Preoperative radiographs were examined carefully to determine the type of fixation device, the osseous condition, and the degree of union of the greater trochanter. The possible loss of bone in the acetabulum from device penetration was also noted.
Surgical Procedure The author, through a lateral approach, performed all procedures. After removal of the failed implant, the resected femoral head was reserved for later autografting. In all patients, the presence of infection was excluded by an intraoperative frozen biopsy of the joint capsule and Gram stain of the joint fluid. The femur was sectioned at its peritrochanteric fracture line. Osseous bars often obstructed the cylindrical anatomy of the proximal end of the distal femur. This initially required a burr hole through the osseous obstacle under image intensifier monitoring. A medullary guide wire was pushed through the distal canal down to the condylar region. Sequential flexible medullary reamers were used to prepare the distal femoral canal until the first circular bone contact of the reamers was achieved. Then the pointed bony fixation area was rasped gently until the rasping gains fixation of at least 6 cm distal to the last femoral shaft screw hole. At this stage, a 2-mm-thicker distal modular stem component was hammered in gently until fixation was achieved. This was assisted by rinsing the canal with warm saline solution to clear medullary debris and to help femoral expansion during implantation, with the additional pouring of warm saline solution on the shaft during stem impaction to help in more femoral expansion (Fig. 1). We performed intraoperative radiographs to rule out fractures and to confirm a 6-cm diaphyseal scratch fit fixation distal to the last osteosynthesis screw hole. In 7 implanted stems, the osteoporotic enlargement of the isthmus necessitated additional fixation using the distal locking screws of the stem.
1384 The Journal of Arthroplasty Vol. 27 No. 7 August 2012
Fig. 1. (A) Rinsing the medullary canal with warm saline solution before stem insertion. (B) Revitan curved cementless modular stem insertion that is 2 mm larger than the last rasp used. (C) Pouring the shaft with warm saline solution during stem impaction.
The proximal trial components and trial heads were then used to adjust the leg length, offset, and the femoral anteversion. The final proximal component and head were then implanted. The trochanteric fragments with the attached abductors were sewn together and fastened to the proximal component by number 2 Ethibond sutures (Ethicon, Somerville, NJ) in addition to cerclage wire loop passed through the 2 medial orifices in the proximal component (Fig. 2). The gap between the reattached trochanter and the distal femur was filled with spongiosa obtained from the femoral head and particles obtained from the reaming process. All of the patients' acetabuli had received replacement by uncemented Trilogy multiholed cup (Zimmer, Warsaw, Ind). Autografts from the femoral head were used in 7 hips to build up secondary acetabular defects. The friction pairing was metal (cobalt-chromium) on highly cross-linked polyethylene. Femoral head size was 32 mm in 1 hip and 36 mm in 15 hips.
All patients received antibiotics before induction of anesthesia and were continued for 5 days postoperatively, and all received postoperative thromboembolic prophylaxis with low-molecular-weight heparin until the patients were fully mobile. No routine prophylaxis for heterotopic ossification was used. The operated hip was not allowed to flex beyond 60° for the initial 5 weeks to avoid movement of the reattached trochanter. The operated limb was kept non–weight-bearing for 3 weeks followed by partial loading with 10 kg for another 3 weeks and then gradually increasing the load 10 kg/wk until full weight-bearing was achieved.
Follow-Up Examination Clinical and radiologic examinations of the patients were carried out at 3 weeks, 6 weeks, 3 months, and 6 months during the first postoperative year and thereafter every 6 months.
Fig. 2. (A) Cerclage wire loop passed through the 2 medial orifices in the final proximal component to reattach the trochanteric fragments. (B) Trochanteric fragments with attached abductors were sewn together by number 2 Ethibond sutures and fastened to the proximal component.
Failed Trochanteric Fracture Fixation Salvage Using Revitan Abouelela
The clinical outcome was evaluated by the author using the HHS combined with examination of the Trendelenburg sign and limb-length discrepancy. The radiographic evaluation consisted of a review of preoperative, postoperative, and the most recent radiographs by a senior consultant with no direct knowledge of the specific cases. The modular femoral stem implantation was assessed by observing the radiographic stabilities and the presence of a periprosthetic radiolucent line according to Engh et al [21]. The percentage of canal fill by the stem was determined using the technique of Tanzer et al [22]. The distal component fixation zone length distal to the last removed osteosynthesis screw hole was measured, and the rate of union of the trochanter was assessed. In addition, subsidence was measured using the technique of Callaghan et al [23]. The reference landmark used to assess subsidence was the distance from the top of the distal component (modular junction) to the most proximal portion of the lesser trochanter. Radiologic signs of stem loosening were the presence of more than 5 mm of progressive subsidence, breakage of interlocking screws, pedestal formation, or a continuous radiolucent line around the stem. The cup osseointegration was evaluated according to the criteria proposed by Moore et al [24]. In addition, the evidence of acetabular loosening was evaluated by the criteria of Massin et al [25] for migration and the zone criteria of DeLee and Charnley [26] for radiolucent lines.
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Results The mean duration of surgery was 170 minutes (range, 140-240 minutes), and the mean estimated blood loss was 1068 mL (range, 500-1400 mL). The mean duration of postoperative follow-up for these patients was 60 months (range, 40-72 months). In the clinical assessment, all patients reported remarkable pain relief and return to ambulation after the conversion to THA. Eight patients had no pain, and 8 had slight awareness of lateral trochanteric lowgrade pain with no compromise of activities. Eight patients ambulated unassisted, 6 used a cane occasionally, and 2 used a cane most of the time. The mean HHS increased from 17.8 points (range, 0-51.2 points) preoperatively to 87.7 points (range, 71.5-100 points) at the last follow-up. A positive Trendelenburg sign was seen in all patients up to 6 months postoperatively. This sign progressively diminished until all patients had a negative Trendelenburg sign at 24 months postoperative. Restoration of leg length equality to within 10 mm was accomplished in all patients. Radiologic assessment of all 16 acetabular cups revealed apparent bone ingrowth, with neither migration nor rotation in any of them. The distal modular component of the stem filled 90% to 100% of the diaphyseal canal in the 16 hips. Cortical bone ingrowth was observed in the distal portion of the modular stem in the 16 hips (Fig. 3). There were neither signs of fibrous ingrowth, pedestal formation, locking screw breakage, nor subsidence.
Fig. 3. (A) Anteroposterior radiograph of a 66-year-old man showing nonunited subtrochanteric fracture with breakage of the side plate. (B) Anteroposterior radiograph 6 years after conversion to THA using Revitan curved cementless modular stem showing excellent osteointegration, full fracture union, and apparent cementless acetabular component bone ingrowth.
1386 The Journal of Arthroplasty Vol. 27 No. 7 August 2012 The mean distal component fixation (distal to last osteosynthesis screw hole) was 7.5 cm (range, 6-10 cm). The trochanter exhibited osseous union to the femoral diaphysis in 15 patients after 6 to 9 months. In 1 patient, trochanteric nonunion persisted, and the trochanter migrated 15 mm proximally and stopped at that level 1 year postoperatively. There was neither infection, dislocation, nor fracture in the operated hips.
Discussion The complexity of conversion THA requires a modular versatile system that can be adapted for proximal femoral bone loss, osteoporotic bone quality, altered anatomy, offset, anteversion, and limb length discrepancy. Revitan modular curved stem could deal with the vast diversity of all of the aforementioned problems. This study's key to success in obtaining primary endosteal diaphyseal fixation along with superior rotational and axial stability was the use of distal stem components 2 mm larger than the last rasp used to maximize the canal fill and fit [18,27-29]. This was aided by rinsing the canal and shaft outer surface with warm saline solution before stem implantation and during stem impaction for more diaphyseal femoral expansion. The author's own idea of insertion of 2-mm oversized distal stem and the warm saline usage during its insertion was based upon the author's anecdotal experience in cementless revision THA. This was proven to be a successful method in this study. The Revitan stem has the advantage of distal locking screws to achieve a strong initial intraoperative fixation until subsequent secondary fixation is achieved, even when the bone quality of the proximal femur was poor and bone loss was severe [30,31]. This was successfully achieved in the 7 osteoporotic hips included in this study. Mahomed et al [32] reported that distal interlocking in press-fit implant increased the torsional stability by 320% and the axial stability by 230%. In this study, no significant subsidence of the femoral implants and no mechanical loosening were seen after a mean follow-up period of 60 months. In addition, no further revision was required during the same follow-up period. These findings are compatible with other results, which emphasize the importance of the initial stability of the revision femoral components [27-31]. The radiologic findings of this study demonstrated healed trochanteric fractures in 15 patients and adequate bone ingrowth around the distal stem in 100% of femora. Therefore, osseointegration into a well-designed and successfully implanted cementless femoral stem can be achieved with good results despite the decreased osteogenic potential in these patients [33,34]. In the current study, no single dislocation occurred among the 16 conversion THAs. This is attributed to the direct lateral approach, which has been shown to have a
lower incidence of dislocation compared with other approaches [35]. Stability was also achieved by correct version placement of the proximal modular component and the restoration of adequate soft tissue tension [36-38]. Moreover, the use of large femoral heads aided in preventing dislocation [39]. Eight patients had slight awareness of pain of low grade with no compromise of activities. The pain was a lateral trochanteric pain only. This presumably was caused by mild trochanteric bursitis secondary to the lateral approach used in this study [40], retained trochanteric fixation devices, or trochanteric nonunion in 1 patient [10]. Thigh pain was not reported by any patient at the latest follow-up in this study, presumably because of stable bony ingrowth into the distal stem, which decreased micromotion at the bone implant interface that eventually prevented thigh pain [41]. Few studies have reported on the use of cementless modular femoral stems in the salvage of failed trochanteric fracture fixation. Laffosse et al [42] treated 29 elderly patients (mean age, 81.1 years) after failed internal fixation of pertrochanteric and intertrochanteric femoral fractures using the Puget prosthesis (Système PP, Tornier, Montbonnot, France). The surviving 23 patients (79%), after a mean follow-up of 20 months, reported significant pain relief and improved function. Stem subsidence was greater than 5 mm in 3 patients. Two patients had nonunion of the greater trochanter, and another 2 patients presented with early dislocation after bipolar hemiarthroplasty. Talmo and Bono [43] reported the results of 10 cementless S-ROM prosthesis (DePuy Orthopedics Inc, Warsaw, Ind) in the salvage of patients with intertrochanteric fracture nonunion. All patients reported good pain relief after a follow-up period of 30 months. The mean HHS in their study was 86. Of the 10 prosthesis, 9 had stable bone ingrowth, with 1 patient having subsidence of 10 mm and significant radiolucency. Thakur et al [44] treated 15 patients after failed internal fixation of pertrochanteric and intertrochanteric fractures with Link MP Hip Stem (Waldemar Link, Hamburg, Germany). After a follow-up period of 2.86 years (range, 2-4.5 years), all patients demonstrated significant pain relief, except in 2 patients who complained of residual trochanteric pain. The mean HHS in their study was 83. Fourteen stems had stable bone ingrowth, and 1 had stable fibrous ingrowth due to undersized implant. Two patients had greater trochanter nonunion. Our results indicated that the distal component of Revitan modular curved revision stem could bypass the weakened distorted proximal femur and could achieve stable fixation in the diaphysis with a 2-mm oversized stem than the last fitting rasp. Its proximal component helped correction of version, application of large
Failed Trochanteric Fracture Fixation Salvage Using Revitan Abouelela
modular heads, restoration of limb length, preservation of remnant proximal bone stock, and reconstruction of abductor mechanism by cerclage wiring and/or heavy sutures that are passed through its 2 medial orifices. Hence, our goals in reduction of pain and restoration of ambulation while avoiding complications such as dislocation and fracture were all met in this study series.
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1388 The Journal of Arthroplasty Vol. 27 No. 7 August 2012 35. Masonis JL, Bourne RB. Surgical approach, abductor function, and total hip arthroplasty dislocation. Clin Orthop Relat Res 2002;405:46. 36. Mahoney CR, Pellicci PM. Complications in primary total hip arthroplasty: avoidance and management of dislocations. Instr Course Lect 2003;52:247. 37. Alberton GM, High WA, Morrey BF. Dislocation after revision total hip arthroplasty: an analysis of risk factors and treatment options. J Bone Joint Surg Am 2002;84: 1788. 38. Asayama I, Chamnongkich S, Simpson KJ, et al. Reconstructed hip joint position and abductor muscle strength after total hip arthroplasty. J Arthroplasty 2005;20:414. 39. Matsushita A, Nakashima Y, Jingushi S, et al. Effects of the femoral offset and the head size on the safe range of motion in total hip arthroplasty. J Arthroplasty 2009; 24:646.
40. Iorio R, Healy WL, Warren PD, et al. Lateral trochanteric pain following primary total hip arthroplasty. J Arthroplasty 2006;21:233. 41. Moreland JR, Moreno MA. Cementless femoral revision arthroplasty of the hip: minimum 5 years follow-up. Clin Orthop Relat Res 2001;393:194. 42. Laffosse JM, Molinier F, Tricoire JL, et al. Cementless modular hip arthroplasty as a salvage operation for failed internal fixation of trochanteric fractures in elderly patients. Acta Orthop Belg 2007;73:729. 43. Talmo CT, Bono JV. Treatment of intertrochanteric nonunion of proximal femur using the S-ROM prosthesis. Orthopedics 2008;31:125. 44. Thakur RR, Deshmukh AJ, Goyal A, et al. Management of failed trochanteric fracture fixation with cementless modular hip arthroplasty using a distally fixing stem. J Arthroplasty 2011;26:398.