Conversion Hip Arthroplasty in Failed Fixation of Intertrochanteric Fracture: A Propensity Score Matching Study

The Journal of Arthroplasty 32 (2017) 1593e1598

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Conversion Hip Arthroplasty in Failed Fixation of Intertrochanteric Fracture: A Propensity Score Matching Study Young-Kyun Lee, MD a, Jung Taek Kim, MD a, *, Awad Abdalla Alkitaini, MD b, Ki-Choul Kim, MD c, Yong-Chan Ha, MD d, Kyung-Hoi Koo, MD a a

Department of Orthopaedic Surgery, Seoul National University Bundang Hospital, Bundang-gu, Seongnam-si, Gyeonggi-do, South Korea Department of Orthopaedic Surgery, Sharg Alneel Hospital, Khartoum, Sudan Department of Orthopaedic Surgery, Dankook University College of Medicine, Dongnam-gu, Cheonan-si, Chungcheongnam-do, South Korea d Department of Orthopaedic Surgery, Chung-Ang University College of Medicine, Dongjak-gu, Seoul, South Korea b c

a r t i c l e i n f o

a b s t r a c t

Article history: Received 16 July 2016 Received in revised form 21 November 2016 Accepted 12 December 2016 Available online 22 December 2016

Background: Conversion hip arthroplasty is a salvage procedure for failed internal fixation of intertrochanteric fractures. However, the technical difficulties and perioperative morbidity of conversion arthroplasty are uncertain. Methods: We compared the type of arthroplasty (total hip arthroplasty or hemiarthroplasty), operative parameters, perioperative morbidity, 1-year mortality, implant stability, and clinical results of 33 conversion hip arthroplasties due to a failed internal fixation of intertrochanteric fracture with those of a matched control group of 33 primary hip arthroplasties due to the same fracture. Propensity score was used for the control matching of gender, age, and body mass index. Results: Total hip arthroplasty was more frequently performed in the conversion group (10/33) compared to the primary group (3/33) (P ¼ .016). The operation time, perioperative blood loss, amount of transfusion, and risk of femoral fracture during the operation were increased in the conversion group. The overall 1-year mortality was 3% (1 patient) in the conversion group and 9% (3 patients) in the primary group (P ¼ .307). At a mean of 3-year follow-up, there was no significant difference in clinical results and none of the implants were loose in both groups. Conclusion: In patients with failed internal fixation of intertrochanteric fracture, conversion hip arthroplasty should be planned and executed, bearing in mind the increased operative morbidities corresponding to operation time, perioperative blood loss, requirement of transfusion, and intraoperative femoral fracture. © 2016 Elsevier Inc. All rights reserved.

Keywords: hip intertrochanteric fracture internal fixation arthroplasty morbidity

Internal fixation is the treatment of choice for most of intertrochanteric fractures. However, fixation is frequently associated with a failure especially in osteoporotic elderly patients. Reportedly, rates of fixation failure ranged from 1.2% to 9.6% [1,2]. Conversion hip arthroplasty is a salvage procedure in patients with this failure [3]. Several studies have reported favorable results of conversion arthroplasty [4,5]. During conversion, previous hardware should be removed and adhesions should be released. Altered anatomical structure owing

No author associated with this paper has disclosed any potential or pertinent conflicts which may be perceived to have impending conflict with this work. For full disclosure statements refer to http://dx.doi.org/10.1016/j.arth.2016.12.018. * Reprint requests: Jung Taek Kim, MD, Department of Orthopaedic Surgery, Seoul National University Bundang Hospital, 82, Gumi-ro 173 Beon-gil, Bundang-gu, Seongnam-si, Gyeonggi-do, 13620, South Korea. http://dx.doi.org/10.1016/j.arth.2016.12.018 0883-5403/© 2016 Elsevier Inc. All rights reserved.

to previous surgery and compromised bone quality due to preexisting osteoporosis and prolonged immobilization often convolute arthroplasty. Due to these technical challenges, conversion arthroplasty might be associated with increased risk of perioperative morbidity [5-9]. Previous studies of conversion hip arthroplasty were case series lacking proper comparative group [10-15] or compared the results with those of conversion arthroplasties due to other reasons than fixation failure of intertrochanteric fracture [8,16,17]. We postulated that there are differences in the type of arthroplasty (total hip arthroplasty [THA] vs hemiarthroplasty [HA]), operative parameters, morbidity, mortality, and outcome of arthroplasty between conversion hip arthroplasty after fixation failure of intertrochanteric fracture and primary arthroplasty for the same fracture. The purpose of our study was to determine whether there were differences in the type of arthroplasty,

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operative parameters, perioperative morbidity, 1-year mortality, and postoperative outcome between conversion hip arthroplasty due to fixation failure and primary hip arthroplasty in intertrochanteric fracture. Materials and Methods Patients The study design and protocol of this retrospective study were approved by the Institutional Review Board in our hospital. Between October 2003 and March 2015, 33 hips in 33 patients, who had been treated previously by internal fixation for intertrochanteric fractures, were converted into hip arthroplasty (HAs or THAs) because of failure of fixation. Among the 33 patients, 26 patients had undergone internal fixation elsewhere and transferred to our institution for the treatment of fixation failure. Fourteen hips were treated with compression hip screw and 19 hips with intramedullary nail. The causes of failure were cutting out in 22 hips, nonunion in 7, cutting through in 2, and metallic failure in 2. There were 10 men (10 hips) and 23 women (23 hips) and the mean age at the time of internal fixation was 74.1 years (range 4592). The mean interval between internal fixation and conversion hip arthroplasty was 11 months (range 0.5-48). The mean age at the time of conversion was 75.1 years (range 47-96). The type of conversion was THA in 10 hips and bipolar HA in 23. The initial fracture pattern was stable in 8 hips and unstable in 25 [18]. Control subjects were matched with each of the 33 hips for gender, age, and body mass index by using propensity score [19] (Table 1). The indication for primary hip arthroplasty was 3-part fractures, loss of posteromedial cortical buttress, and severe osteoporosis (Singer index  4). All 33 fractures were unstable fracture patterns in the control group [18]. Surgical Techniques To rule out infection, we routinely performed hematologic tests including complete blood cell count, erythrocyte sedimentation rate, and C-reactive protein (CRP) before arthroplasty. When there was an unexplained elevation of erythrocyte sedimentation rate, C-reactive protein, and/or white blood cell count in preoperative laboratory workup, we analyzed joint aspirate using sonography before arthroplasty. All 33 conversion hip arthroplasties were carried out through the posterolateral approach. Femoral head was dislocated before removal of previously inserted implant for fixation, in order to prevent femoral fracture. After the removal of fixation devices, the femoral head was removed and femoral canal was prepared. We used a gauge osteotome and/or a burr to remove endosteal sclerotic bone, which was formed in the proximal femur along the lag screw. Special attention was paid to remove sclerotic bone in the medial portion of the femoral neck and the lateral portion of

Table 1 Patient Demographic Data.

Male/Female Age at hip arthroplasty (y) BMI (kg/m2) Preinjury Koval score ASA score

Conversion Group (n ¼ 33)

Control Group (n ¼ 33)

P Value

10/23 75.1 ± 23.4 ± 2.8 ± 1.6 ±

11/22 75.1 ± 23.5 ± 2.6 ± 1.6 ±

1.000 .991 .896 .746 .926

11.0 4.0 1.9 0.07

10.4 3.5 1.9 0.5

BMI, body mass index, ASA, American Society of Anesthesiologists physical status classification.

subtrochanteric area to avoid varus or valgus positioning of the stem. We tried to place the femoral component at 15 of anteversion according to the horizontal axis of the knee joint, instead of referencing axis of the femoral neck, because of postoperative deformity in the proximal femur. In case of THA, we tried to place the acetabular component at 15 of anteversion and 40 -45 of abduction angle. Cups and stems were inserted in a press-fit manner. We also used posterolateral approach in all primary hip arthroplasties. After the insertion of cementless stem, the greater trochanteric and the medial fracture fragments were reduced and fixed with 2-4, 16-gauge wires. In case of THA, target position of the acetabular cup was the same as that of the conversion group. Implants Cementless implants were used in all patients in both groups. We exclusively used cementless stems even in elderly patients, because of concerns of cement-related cardiopulmonary complications [20]. For the conversion group, Bencox II stem (Corentec, Cheonan, South Korea) was used in 9 hips, BiCONTACT® stem (Aesculap, Tuttlingen, Germany) in 7, KAR stem (DePuy, Warsaw, IN) in 6, COREN POROFIX (Corentec) in 4, Bencox ID stem (Corentec) in 2, and Bencox stem (Corentec) in 2. Bencox M stem (Corentec), CORAIL (DePuy), and ML taper stem (Zimmer, Warsaw, IN) were used in one hip each. In 10 patients, who were treated with THA, COREN cup (Corentec) was used in 6 hips, PLASMACUP® SC (Aesculap) in 2 hips, Trilogy cup (Zimmer) in 1 hip, and Pinnacle cup (DePuy) in 1 hip. Alumina ceramic head (BIOLOX® forte; CeramTec AG, Plochingen, Germany) was used in 21 hips, Delta ceramic head (BIOLOX delta, CeramTec) in 7 hips, and CoCr head in 5 hips. In 23 HAs, ultra-highmolecular-weight polyethylene (UHMWPE) liner was coupled with all 5 metal heads and 18 alumina ceramic heads. In 10 THAs, all 7 Delta ceramic heads were coupled with Delta ceramic liners, 2 alumina ceramic heads with alumina ceramic liners, and 1 alumina ceramic head with UHMWPE liner. The diameter of the femoral head was 28 mm in 23 hips, 32 mm in 8 hips, 22 mm in 1 hip, and 36 mm in 1 hip. For the control group, KAR stem (DePuy) was used in 10 hips, Bencox stem (Corentec) in 8, COREN POROFIX (Corentec) in 5, BiCONTACT stem (Aesculap) in 5, CORAIL (DePuy) in 3, and Bencox II stem (Corentec) in 2. In 3 patients, who were treated with THA, Pinnacle cup (DePuy) was used and all 3 Delta ceramic liners were coupled with Delta ceramic heads. In 30 HAs, UHMWPE liner was coupled with 11 metal heads and 19 alumina ceramic heads. Alumina ceramic head was used in 19 hips, Delta ceramic head in 3 hips, and CoCr head in 11 hips. The diameter of the femoral head was 28 mm in 27 hips, 22 mm in 3 hips, 36 mm in 2 hips, and 32 mm in 1 hip. Postoperative Care With Assessment Patients were instructed to walk with partial weight bearing with the aid of 2 crutches for 4 weeks after surgery. All patients had mechanical prophylaxis of venous thromboembolism by an intermittent pneumatic compression device. Follow-up evaluations were performed at 6 weeks; at 3, 6, 9, and 12 months, and every year thereafter. Patients who had not returned for regular scheduled visits were contacted by telephone. These 33 patients (33 hips) were followed up for an average of 3.0 years (range 0.5-11.3) after conversion hip arthroplasty. We compared the type of arthroplasty (THA or HA), operation time, broken screw which was left, perioperative blood loss, requirement of transfusion, cup position and stem alignment, intraoperative complications, and hospital stay between the

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conversion group and the control group. We also compared postoperative complications, reoperation for any reason, ambulatory ability, postoperative 1-year mortality, and radiological results at final follow-up. The ambulatory ability before injury was informed from patients or their family members at the time of admission and classified according to Koval's categories [21]. Alignments of the femoral stems and limb length discrepancy were measured on 6-week anteroposterior radiographs. Stem alignment was determined by measuring the angle formed between the longitudinal axis of the femoral stem and the longitudinal axis of the femoral canal [22,23]. The alignment of the stem was classified as neutral, valgus (>5 of lateral deviation), or varus (>5 of medial deviation) [22]. The limb length discrepancy was measured from the intertear drop line to lower margin of the lesser trochanter, and the involved limb was compared with the contralateral limb [24]. In THA cases, acetabular cup orientation was evaluated in terms of abduction and anteversion. The abduction angle of the acetabular component was measured using the method described by Engh et al [25,26]. The anteversion of the acetabular component was calculated using the method of Widmer [27]. The radiographic evaluation was done by 2 independent observers who did not participate in either internal fixation or arthroplasty. The 6-week or 3-month anteroposterior and crosstable lateral radiographs were considered to be the baseline studies for radiographic comparison. The final radiographic evaluation included an assessment of the fixation of the acetabular and femoral components, wear, osteolysis, and heterotopic ossification. Fixation of the femoral component was classified with use of the method of Engh et al [28] and fixation of the acetabular component with use of the method of Latimer and Lachiewicz [29]. The wear of liner was calculated according to the method developed by Livermore et al [30]. Osteolytic lesions were defined according the criteria of Engh et al [31]. The lesions were recorded according to the 3 zones described by DeLee and Charnley [32] on the acetabular side and the 7 zones described by Gruen et al. [33] on the femoral side. Heterotopic ossification was classified according to the system of Brooker et al [34]. Statistical Methods For selection of the control group, a propensity-score matching method was used [19]. The factors considered to be the most important confounders affecting surgical parameters and outcome were chosen for the propensity-score algorithm. These factors were chosen based on consensus among the investigators. A logistic model with conversion arthroplasty as the outcome and gender, age, and body mass index as confounders was used to estimate propensity score. We then matched each conversion arthroplasty patient to a control subject based on the propensity score. The maximum difference between propensity probabilities for matching was set at 0.1. We used Fisher's exact test for categorical variables and the Mann-Whitney U-test for numerical variables to compare the results of both groups. All reported P values were 2 sided, and P value <.05 was used to determine statistical significance. All hips were assumed to be independent in the statistical analysis. For all statistical analyses, we used SPSS version 15.0 (SPSS, Chicago, IL). Results THA was more prevalent in the conversion group (10/33) than in the primary group (3/33) (P ¼ .016). The broken screws were left inside in 2 patients with conversion procedure. The operation time was longer (P < .001), perioperative blood loss was greater

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Table 2 Perioperative Morbidity, Implant Position, and Results. Conversion Group Type of arthroplasty Total hip arthroplasty Hemiarthroplasty Operating time (min) Perioperative blood loss (mL) Amount of transfusion (mL) Hospital stay (d) Intraoperative femoral crack One-year mortality Postoperative LLD (cm) Cup abduction ( ) Cup anteversion ( ) Stem malposition Postoperative periprosthetic fracture Reoperation on any reason Koval score at last follow-up Follow-up duration

157.5 1376.8 1182.4 14.5

0.5 41.8 23.0

10 23 ± 42.1 ± 617.3 ± 656.2 ± 17.6 5 1 ± 1.0 ± 2.8 ± 10.0 2a 1

1 2.9 ± 1.8 3.0 ± 2.5

Primary Group

P Value

3 .016 30 99.8 ± 26.0 <.001 682.4 ± 285.2 <.001 832.0 ± 398.7 .015 22.7 ± 28.3 .165 0 .027 3 .307 0.1 ± 0.1 .151 42.0 ± 1.0 .909 20.0 ± 4.4 .630 0 .246 0 .500 0 2.9 ± 1.8 3.7 ± 2.6

.500 .996 .274

LLD, limb length discrepancy. a Varus and valgus alignment of stem in 1 hip each.

(P < .001), and the amount of transfusion was larger (P ¼ .015) in the conversion group than in the primary group (Table 2). Proximal femoral cracks occurred in 5 conversion hips during insertion of stem, which were treated with cerclage wires. There were no significant differences in stem malposition and 1-year mortality after arthroplasty between the 2 groups. The cup position, postoperative leg length discrepancy, and ambulatory ability at last follow-up were similar between the 2 groups. No patient in any group had symptomatic venous thromboembolism or periprosthetic joint infection after arthroplasty. Vancouver type B1 periprosthetic femoral fracture occurred through the cortical hole of previously removed screw in 1 converted hip due to a fall at postoperative 7 weeks [35]. This fracture was treated successfully with open reduction and internal fixation which was the only reoperation for any reasons in both groups (Fig. 1A-D). One patient in the conversion group and 3 patients in the primary group died within 1 year after arthroplasty (P ¼ .307). All acetabular cups and femoral stems had radiographic evidence of bone ingrown stability at the time of last follow-up. There was no detectable wear and no periprosthetic osteolysis in both groups (Fig. 2). Brooker grade I or II heterotopic ossification developed in 2 conversion hips and 2 primary hips. None of both groups experienced dislocation till the last follow-up.

Discussion During conversion hip arthroplasty after failed fixation of intertrochanteric fractures, surgeons face several challenging problems, including removal of previous fixation devices, difficult surgical dissection due to postoperative adhesion and scar tissue, anatomical alteration of the proximal femur, compromised bone quality due to pre-existing osteoporosis, and prolonged immobilization [5,6,8,9]. These problems might result in longer operating time, more perioperative blood loss, and higher requirement of transfusion in conversion arthroplasty than usual [5-7,36]. Screw holes leave cortical defects, which increase the risk of fracture due to a stress riser mechanism [37]. In addition, hard sclerotic endosteal bone around the previously used intramedullary nail and screws may lead to fracture of the femur during insertion of the stem. The risk of intraoperative femoral fracture in conversion arthroplasty had ranged up to 32% [10,11,13].

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Fig. 1. A 79-year-old man had been operated with proximal femoral nail for intertrochanteric fracture. (A) The anteroposterior radiograph at 9 months shows nonunion of the fracture and breakage of nail (arrow head). (B) He underwent a conversion bipolar hip arthroplasty. The anteroposterior radiograph at 6 weeks shows no abnormal sign. (C) He slipped down 7 weeks after the arthroplasty and sustained Vancouver type B1 periprosthetic femoral fracture. (D) The fracture was treated with open reduction and internal fixation with plate and screws. The anteroposterior radiograph at 38 months after the fixation shows complete union of the periprosthetic fracture.

The most common mode of fixation failure in intertrochanteric fractures was cutting out of the lag screw [38-42]. The consequent damage of the acetabular cartilage necessitates acetabular replacement in conversion arthroplasty.

Several studies have reported the results of conversion hip arthroplasty with use of cemented prosthesis [5,6,43]. Cement may leak through screw holes and result in nonunion at the fracture site or postoperative periprosthetic fracture [44-47]. Moreover, there

Fig. 2. A 60-year-old woman had been treated elsewhere with sliding hip screw for intertrochanteric fracture. (A) Two years later, she was transferred to our hospital. Radiograph shows signs of fixation failure: radiolucent line around lag screw, excessive sliding of lag screw, 2 broken screws, and necrotic change of femoral head. (B) She underwent a conversion total hip arthroplasty. The 6-week radiograph shows an optimal cup position and neutral alignment of the stem. The screw holes were filled with autologous bone graft from the femoral neck. Unstable fragments were fixed with wires. (C) Four-year radiograph shows well-fixed implants, union of fracture fragments, and obliteration of cortical screw defects.

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Table 3 Previous Studies Regarding Cementless Conversion Arthroplasty for Failed Fixation of Intertrochanteric Fracture. Incidence of Reoperation for Any Reasonsa

Incidence of Intraopereative Fracturea

Dislocationa

11 (4-50)

5 (8.3%)

2 (3.3%)

1 (1.7%)

64 (21-87) 71 (NR)

40.3 (2-288) 26 (NR)

0 (0%) 2 (5.6%)

7 (32%) 5 (13.9%)

3 (15.8%) 0 (0%)

29, 0 10, 0 20, 1

81 (70-91) 79 (67-85) 75 (61-85)

2 (0-5) 12.9 (4-8) <1 y (NR)

NR 0 (0%) 0 (0%)

0 (0%) 0 (0%) 1 (4.8%)

2 (6.9%) 0 (0%) 0 (0%)

15 INT 20 STN, 10 INT 12 INT, 4 STN

15, 0 30, 0 16, 0

80 (70-92) 77 (52-93) 64 (46-74)

3.75 (1-8) NR 10.9 (5-22)

0 (0%) 7 (23%) 0 (0%)

0 (0%) NR NR

0 (0%) 2 (6.7%) 0 (0%)

83 FNF, 71 INT

147, 7

73 (32-93)

NR

6 (8.5%)

3 (4.2%)

0 (0%)

91 INT 20 INT, 24 FNF, 2 STN 39 INT, 63 FNF

70, 21 41, 5 52, 50

65 (23-86) 64 (22-91) 70 (30-96)

NR 42 (0.75-240) NR

NR 6 (13.0%) 7 (6.9%)

2 (2.2%) 4 (8.7%) NR

2 (2.2%) 3 (6.5%) 5 (4.9%)

31 INT 33 INT

31, 0 33, 0

72 (59-85) 75 (47-96)

8.2 (5-6) 11 (0.5-48)

0 (0%) 1 (3.0%)

2 (6.5%) 5 (15.2%)

2 (6.5%) 0 (0%)

Number and Type of Femoral Stem (Cementless, Cemented)

Mean Age (y)

Study

Number and Type of Hip Fractures

Haidukewych and Berry [5] Zhang et al [6] Winemaker et al [7] Laffosse et al [14] Talmo et al [16] D'Arrigo et al [49] Thakur et al [15] Weiss et al [13] Abouelela et al [12] Mortazavi et al [17] Pui et al [50] DeHaan et al [8] Archibeck et al [11] Shi et al [10] This study

60 INT

3, 57

78 (54-96)

19 INT 36 (type: NR)

3, 16 23, 13

29 INT 5 INT, 5 STN 21 INT

Time to Fixation Failure (mo)

FNF, femur neck fracture; INT, intertrochanteric fracture; STN, subtrochanteric fracture; NR, not reported. a Number of hips and percentage.

might be a cement-related cardiovascular event in elderly patients [20]. Other studies reviewed limited number of conversion arthroplasties without comparison [5,6,43], evaluated inhomogeneous subjects including trochanteric fractures and femoral neck fractures [7,48], or compared with conversion arthroplasties due to failed fixation of the femoral neck fracture [17]. Recent studies of conversion arthroplasty using cementless prosthesis favored modular long stems (Table 3) [8,12-16]. Although modular stem has several advantages of individual adjustments for leg length, offset, and anteversion for distorted anatomy of femur, there are concerns about mechanical failure or dissociation of modular components, and corrosion and metal ion release at the modular junction [51-53]. In our study, nonmodular monolithic cementless stems were exclusively used in consecutive patients. Because of the concern of cement-related cardiopulmonary complications, we did not use cemented prostheses in our patients [20]. THA was more frequently performed in the conversion group than in the primary group. In the conversion group, operating time, perioperative blood loss, requirement of transfusion, and periprosthetic femoral fracture were increased than in the primary group. The 1-year mortality and 3-year results were similar between the conversion group and the primary group. In our study, the average age of the patients was 74 years and ceramic-on-ceramic bearing was used in 9 of the 10 THAs. In previous studies, old age did not increase the risk of dislocation after THA with use of ceramic-on-ceramic bearing [54,55]. Thus, we did not limit the use of ceramic bearing even in elderly patients, if the patient was active. There are several limitations in our study. As we exclusively used cementless prosthesis in our patients, we could not provide the comparison of cemented prosthesis. The study was a retrospective one with limited number of patients and the follow-up period was short. However, long-term follow-up is barely possible in elderly osteoporotic patients, who had conversion hip arthroplasty for failed fixation of intertrochanteric fracture. We performed a comparative study using propensity score matching. To the best of our knowledge, none performed a comparative study in regards to the results of cementless conversion arthroplasty with

those of primary arthroplasty. This paucity of comparison makes surgeons hard to explain the difficulty and morbidity of conversion arthroplasty to their patients. Our comparisons provide the quantitative data on conversion-related difficulty and morbidity. When performing conversion arthroplasty for failed internal fixation, the surgeon should bear the increased perioperative morbidities of this challenging procedure in mind, and counsel their patients on increased morbidities. References 1. Matre K, Havelin LI, Gjertsen JE, et al. Sliding hip screw versus IM nail in reverse oblique trochanteric and subtrochanteric fractures. A study of 2716 patients in the Norwegian Hip Fracture Register. Injury 2013;44(6):735. 2. Ovesen O, Andersen M, Poulsen T, et al. The trochanteric gamma nail versus the dynamic hip screw: a prospective randomised study. One-year follow-up of 146 intertrochanteric fractures. Hip Int 2006;16(4):293. 3. Petrie J, Sassoon A, Haidukewych GJ. When femoral fracture fixation fails: salvage options. Bone Joint J 2013;95-B(11 Suppl A):7. 4. Haentjens P, Casteleyn PP, Opdecam P. Hip arthroplasty for failed internal fixation of intertrochanteric and subtrochanteric fractures in the elderly patient. Arch Orthop Trauma Surg 1994;113(4):222. 5. Haidukewych GJ, Berry DJ. Hip arthroplasty for salvage of failed treatment of intertrochanteric hip fractures. J Bone Joint Surg Am 2003;85-A(5):899. 6. Zhang B, Chiu KY, Wang M. Hip arthroplasty for failed internal fixation of intertrochanteric fractures. J Arthroplasty 2004;19(3):329. 7. Winemaker M, Gamble P, Petruccelli D, et al. Short-term outcomes of total hip arthroplasty after complications of open reduction internal fixation for hip fracture. J Arthroplasty 2006;21(5):682. 8. DeHaan AM, Groat T, Priddy M, et al. Salvage hip arthroplasty after failed fixation of proximal femur fractures. J Arthroplasty 2013;28(5):855. 9. Angelini M, McKee MD, Waddell JP, et al. Salvage of failed hip fracture fixation. J Orthop Trauma 2009;23(6):471. 10. Shi X, Zhou Z, Yang J, et al. Total hip arthroplasty using non-modular cementless long-stem distal fixation for salvage of failed internal fixation of intertrochanteric fracture. J Arthroplasty 2015;30(11):1999. 11. Archibeck MJ, Carothers JT, Tripuraneni KR, et al. Total hip arthroplasty after failed internal fixation of proximal femoral fractures. J Arthroplasty 2013;28(1): 168. 12. Abouelela AA. Salvage of failed trochanteric fracture fixation using the Revitan curved cementless modular hip arthroplasty. J Arthroplasty 2012;27(7):1382. 13. Weiss RJ, Karrholm J, Hailer NP, et al. Salvage of failed trochanteric and subtrochanteric fractures using a distally fixed, modular, uncemented hip revision stem. Acta Orthop 2012;83(5):488. 14. 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(6):729.

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