Abstract
Background
Hip hemiarthroplasty (HA) is a standard surgical procedure for elderly patients with displaced fracture of the femoral neck, where dislocation is a possible complication. This study is a systematic review on the risk factors of implant dislocation in patients with femoral neck fracture following hip hemiarthroplasty (HA), and evaluates the methodological quality of the included studies.
Methods
Studies on risk factor assessment of dislocation following hip HA were sourced from EMBASE, Ovid, PubMed and ScienceDirect databases. The quality of included studies was evaluated using an improved quality evaluation method combined with a best-evidence synthesis method.
Results
A total of 130,127 patients were involved in 17 observational studies included in this systematic review, with a dislocation rate that ranged between 0.76 and 12.2% (overall incidence was 4–5% by meta-analysis). According to the applied quality evaluation criteria, eight studies were considered to be of high quality, six to be of medium quality, and three to be of low quality. The posterolateral surgical approach was identified as the only risk factor supported by strong evidence, while patients with small acetabular coverage and low postoperative offset were identified as risk factors supported by moderate evidence, and 11 other risk factors were supported by limited evidence.
Conclusion
This systematic review provides some evidence in helping surgeons develop optimal prevention strategies for dislocation following hip HA during the perioperative period based on common risk factors identified in the literature. However, conclusive evidence supporting most of these risk factors is lacking and more methodologically rigorous studies are required to increase the confidence of recommendations.
Electronic supplementary material
The online version of this article (10.1007/s43465-020-00177-5) contains supplementary material, which is available to authorized users.
Keywords: Hip hemiarthroplasty, Dislocation, Risk factor, systematic review
Introduction
Hip hemiarthroplasty (HA) is the standard surgical procedure for the vast majority of elderly patients with displaced fracture of the femoral neck due to its relatively short operating time and prompt recovery [1, 2]. It was first introduced in 1940 by Moore and Bolhman, and the Austin-Moore endoprosthesis was later introduced in the 1980s [3]. The surgical technique led to improved functional outcomes and decreased mortality during the perioperative period [4]. Compared with total hip arthroplasty and internal fixation, hip HA produced a lower rate of dislocation and better clinical outcomes [5].
Although hip HA results in optimal postoperative mobility and regain of physical function, a small percentage of patients still experience unexpected complications including dislocation, aseptic loosening, infection, pulmonary embolism, and sciatic nerve damage. Dislocation is the most widely investigated complication associated with hip HA, which can lead to substantial morbidity [6], persisting deterioration in the health-related quality of life (HRQoL) [7], increased mortality risk [8] and associated with healthcare and socioeconomic burdens [9, 10]. Some patients with dislocation have even required open revision for reduction. The incidence of dislocation following hip HA is influenced by patient characteristics, prosthesis design, and surgical technique. Identifying and evaluating the risk factors of dislocation have remained a highly active research topic to reduce the complications associated with hip HA.
Many studies have successfully identified risk factors for dislocation in patients after undergoing hip HA. However, conclusive evidence is rare and some studies have presented contradicting results. Some of the prominent risk factors for dislocation after hip HA include posterolateral surgical approach; patients with small acetabular coverage; considerable change in postoperative offset of the hip; decreased postoperative global femoral offset (FO), leg length discrepancy (LLD) and smaller Wiberg angle; and residual length of the femoral neck > 0.5 cm in short patients. Some of these risk factors are alterable and may need to be counteracted by surgical technique, while some others are irreversible following the surgery. Orthopaedic surgeons therefore need to draw on well-defined guidelines to make informed choices on determining the surgical procedure for hip HA to minimise the risk of postoperative dislocation.
This study presents an updated systematic review of risk factors for dislocation following hip HA. This study aims to inform surgeons on the most important risk factors to consider for dislocation following hip HA based on the current evidence and quality of this evidence.
Materials and Methods
Search Strategy
Methods used in this review were based on the guidance on systematic reviews from the Centre for Reviews and Dissemination [11, 12], guidelines on meta-analysis of observational studies in epidemiology, and first choice reporting items for meta-analyses and systematic reviews [13, 14]. Studies published until December 2019 were sourced from EMBASE, Ovid, PubMed and ScienceDirect databases with no lower date limit. MeSH terms used for performing the search were: “hip dislocation”, “risk factors”, “arthroplasties, replacement, hip”, “femoral neck fracture”, and “hemiarthroplasty”. In addition, the reference list of relevant systematic reviews and meta-analyses were scanned to identify potentially eligible studies. Citations were exported to Endnote and duplicates were removed before the titles, abstracts, and full texts of publications were assessed for eligibility. This research has been approved by the Institutional Review Board of the authors’ affiliated institutions. Detailed methods for study retrieval are included in the supplementary materials. The protocol for this review has been pre-registered in PROTERO (104229).
Study Selection
Publications were included for analysis in this study if they satisfied the following criteria: (1) observational study; (2) investigated the risk factors for dislocation or re-dislocation after hip HA; (3) consisted of a well-defined group of patients who underwent hip HA. Publications were excluded from analysis if they belonged to one of the following categories: (1) total hip arthroplasty (THA); (2) changing from hip HA to THA; and (3) biomechanical studies, case reports, and reviews.
According to the above inclusion and exclusion criteria, publications retrieved from the search had their title and abstract independently analysed by two reviewers, and eligible publications were included for further analysis. A discussion between the two reviewers was used to resolve any disagreements such that a consensus could be reached.
Data Extraction
Data from the included studies were independently extracted by two reviewers, including: lead author, year and country of publication; study design; study duration; patient characteristics; sample size; number of initial HA procedures; incidence of dislocation; and mean follow-up period. In the case that inconsistent data was extracted by the two reviewers from any of the studies, a third reviewer independently extracted the data and any disagreements were resolved by discussion.
Quality Assessment of Included Studies
For each of the included studies, the quality of its research methodology was evaluated based on a defined list of criteria [15] (Table 1). Comparable criteria have been previously applied for methodological quality assessment in similar types of systematic reviews for observational studies [12, 16–18]. The study quality was evaluated by giving it a score out of a full score of 9 according to its compliance with the defined criteria. This quality score was then used to classify the quality level of the study as high, medium or low (Table 2).
Table 1.
Criteria for the assessment of the methodological quality of observational study
| Item | Criterion | Score |
|---|---|---|
| Study population | Sample size ≥ 100 and participation rate ≥ 80% | 1 |
| Patient selection | For cohort study; case and controls draw from the same population; for case–control studies; selected group was representative of the population with hemiarthroplasty | 1 |
| Study design | Cohort design | 2 |
| Retrospective case–control design | 1 | |
| Reported the duration of follow-up | 1 | |
| Study withdrawal rate ≤ 20% | 1 | |
| Analysis and data presentation | Appropriate analysis techniques were used | 1 |
| Multivariable regression analysis performed | 1 | |
| Frequencies of most important outcomes were given | 1 |
Table 2.
Criteria for assessment of the quality of the included studies and best evidence synthesis
| Item | Level | Criterion for inclusion |
|---|---|---|
| Level of studies | High-quality studies | Multivariate analysis performed and had a quality score ≥ 8 |
| Moderate-quality studies | Multivariate analysis performed, but had a quality score ≤ 8 | |
| No multivariate analysis performed and had a quality score ≥ 6 | ||
| Low-quality studies | No multivariate analysis performed and had a quality score < 6 | |
| Level of evidence | Strong | Minimum of 3 high-quality studies with generally consistent findings |
| Moderate | Minimum of 2 moderate- studies with generally consistent findings | |
| Limited | Minimum of 1 low-quality studies with generally consistent findings | |
| None | No studies could be found |
Evidence Synthesis
The strength of evidence regarding a particular aspect of research, in this case the different risk factors contributing to dislocation following hip HA was determined according to the quantity and quality of research and consistency of research results contributing to each identified risk factor [16]. A best-evidence synthesis was used to summarise the results of individual studies, providing a unique outcome that includes both the quality and the results of the research [12, 18]. The grading system used in this study was based on key elements suggested by the US Agency for Healthcare Research and Quality [19], rating the strength of evidence for risk factors by 4 levels: strong, moderate, limited and none (Table 2). “Strong evidence” indicated that the evidence was unlikely to be changed by further research. “Moderate evidence” indicated that the evidence may be impacted by further research and future changes are possible. “Limited evidence” indicated that the evidence was highly likely to be changed by further research. “No evidence” indicated that the item of interest has not been discussed in the included studies or necessary statistical analysis has not been performed.
Results
Studies Included for Analysis
After removing duplicated citations from the retrieved studies, a total of 115 publications were identified as being suitable for inclusion after screening their titles and abstracts. From these studies, 17 were selected for further analysis after reading the full text to ensure that they complied with all defined inclusion and exclusion criteria [2–4, 6–8, 20–30] (Fig. 1).
Fig. 1.
Flow diagram for the identification of included studies
Study Characteristics
Characteristics of the included studies are shown in Table 3. The 17 included studies involved 130,127 patients with femoral neck fracture who underwent hip HA, and reported on the risk factors for postoperative dislocation. The studies were published between 1994 and 2015, comprising 2 case–control studies (937 patients) and 15 cohort studies (129,190 patients). The 17 studies were retrospective, with sample size ranging from 82 to 11,552 patients. The incidence of dislocation following hip HA ranged from 0.76 to 12.2%. A meta-analysis was used to illustrate the overall incidence of dislocation (4–5%; Fig. 2). The average follow-up period ranged between 1.5 to 84 months, but was not reported for all studies.
Table 3.
Characteristics and quality assessment of the included studies
| Study | Year | Country | Study Design | Study duration | Age | Sex (male/female) | Sample size | No of initial HA | Incidence of dislocation | Mean follow-up (mths) | Quality score | Quality level of study | |||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Case | Ctrl | Case | Ctrl | Case | Ctrl | ||||||||||
| Enocson [6] | 2008 | Sweden | Cohort | 1996–2003 | 82.5 ± 7.4 | 84.2 ± 7.2 | 6/39 | 141/553 | 45 | 694 | 739 | 6.1% | 27 | 8 | High |
| Madanat [20] | 2012 | Finland | Case–control | 2002–2008 | 78.5 | 78.2 | 7/27 | 27/69 | 34 | 96 | 602 | 5.6% | > 24 | 9 | High |
| Mukka [21] | 2015 | Sweden | Cohort | 2006–2013 | 82 ± 6 | 84 ± 6 | 18/22 | NA | 40 | 288 | 373 | 10.7% | 6–84 | 7 | Moderate |
| Pajarinen [22] | 2003 | Sweden | Case–control | 2000–2001 | 82 | 82 | 5/17 | NA | 22 | 79 | 335 | 7% | > 6 | 8 | High |
| Salem [23] | 2014 | UK | Cohort | 1999–2010 | 79.5 ± 8 | 82 ± 8 | 4/23 | 770/2728 | 27 | 3498 | 3525 | 0.76% | 27 | 8 | High |
| Ninh [8] | 2009 | US | Cohort | 2000–2004 | 77.3 ± 11.8 | 68/149 | 13 | 204 | 217 | 6% | 1.5–12 | 8 | High | ||
| Suh [24] | 2012 | Korea | Cohort | 1996–2008 | 76.5 | 68/122 | 5 | 185 | 190 | 2.6% | 36.5 | 7 | Moderate | ||
| Sierra [25] | 2006 | US | Cohort | 1974–2001 | 63 | NA | 8/25 | NA | 32 | 1780 | 1812 | 1.8% | 40.8 | 8 | High |
| Langlois [2] | 2015 | France | Cohort | 2012–2012 | 86.5 | 21/61 | 10 | 72 | 82 | 12.2% | 21 | 6 | Moderate | ||
| Biber [26] | 2012 | Germany | Cohort | 2006–2011 | 80.4 ± 9.8 | 212/492 | 28 | 676 | 704 | 3.9% | NA | 7 | Moderate | ||
| Abram [27] | 2014 | UK | Cohort | 2008–2013 | 83 | 232/575 | 23 | 784 | 807 | 2.9% | 12 | 8 | High | ||
| Saberi [4] | 2014 | Iran | Cohort | 2007–2012 | 71.4 | 82/68 | 10 | 140 | 150 | 6.6% | 12 | 4 | Low | ||
| Ames [28] | 2010 | US | Cohort | 1994–1995 | 81.8 | 24,732/90,620 | 5714 | 109,638 | 115,352 | 5.0% | 60 | 7 | Moderate | ||
| Enocson [7] | 2009 | Sweden | Cohort | 2003–2003 | 82.3 | 4/17 | NA | 21 | 298 | 319 | 6.5% | 12 | 8 | High | |
| Unwin [3] | 1994 | UK | Cohort | 1986–1992 | NA | NA | 190 | 2716 | 2906 | 6.5% | 3 | 4 | Low | ||
| Keene [29] | 1994 | UK | Cohort | NA | 81 | 74/457 | 15 | 516 | 531 | 2.8% | 12 | 5 | Low | ||
| Ko.c.k [30] | 2001 | Hong Kong | Cohort | 1986–1997 | 81.2 | 658/825 | 28 | 1455 | 1483 | 1.9% | 3–18 | 6 | Moderate | ||
Fig. 2.
Meta-analysis of included studies
Study Quality
The methodological quality of the included studies was evaluated and the quality scores together with quality level of the studies are presented in Table 3. From the 17 studies, 1 study (5.9%) scored 9 points, 7 studies (41.2%) scored 8 points, 4 studies (23.5%) scored 7 points, 2 studies (11.8%) scored 6 points, 1 study (5.9%) scored 5 points, and 2 studies (11.8%) scored 4 points. According to these quality scores and whether multivariate analysis was performed in the study, the studies were classified by quality level (Table 2). From the 17 studies, 8 studies (8,356 patients) had high quality, 6 studies (118,184 patients) had moderate quality, and 3 studies (3,587 patients) had low quality.
Strength of Evidence Supporting Identified Risk Factors
From the 17 included studies, a total of 14 potential risk factors for dislocation after hip HA were identified (Tables 4, 5). Posterolateral approach was the only risk factor that was supported by strong evidence, which was supported by three high-quality, four moderate-quality, and three low-quality studies. Risk factors supported by moderate evidence were patients with small acetabular coverage, and considerable change in postoperative offset of the hip. The other identified risk factors were supported by limited evidence, including decreased postoperative global FO, LLD and Wiberg angle; residual length of the femoral neck > 0.5 cm in short patients; delay in surgery of > 24 h; cemented hip hemiarthroplasty; mental disease; small femoral neck; patients with Bateman prostheses and osteonecrosis; left-side surgery; surgeon volume for total hip arthroplasty; and gender.
Table 4.
Risk factors for dislocation after hip hemiarthroplasty
| Study | Risk factors investigated in individual study | Significant risk factors |
|---|---|---|
| Enocson [6] | Age, sex, indication, surgeon’s experience, type of HA, surgical approach | Posterolateral approach |
| Madanat [20] | Age, gender, body mass index, dementia, alcoholism, living conditions, (ASA) class, time of surgery and surgeon experience | Posterolateral surgical approach, patients with smaller acetabular coverage, smaller offset |
| Mukka [21] | Age, sex, ASA classes, global FO, LLD, Wiberg angle, 1 year mortality, mental status | Decreased postoperative global FO, LLD and smaller Wiberg angle |
| Pajarinen [22] | Sex, age, height (cm), difference in the offset compared to opposite hip, length of residual femoral neck | Length of the residual femoral neck > 0.5 cm in short patients (< 165 cm), considerable change in postoperative offset of the hip |
| Salem [23] | Grade of surgeon, delay in surgery, type of implant and operative time, postoperative complications and mortality | Delay in surgery of > 24 h, cemented hip hemiarthroplasty |
| Ninh [8] | Femoral neck offset, contralateral femoral neck offset, ratio of femoral neck offset, residual femoral neck, prosthesis femoral neck shaft angle, acetabular index, centre edge angle of Wiberg | Male sex, mental disease, smaller femoral neck, contralateral femoral neck offset, smaller centre edge angle |
| Suh [24] | Sex, age, follow-up period, diameter of acetabular shell, diameter of femoral head limb length discrepancy, femoral offset, neuromuscular disease | Posterior approach |
| Sierra [25] | Gender, surgical approach, diagnosis, decade of surgery with dislocation | Patients with Bateman prostheses and osteonecrosis |
| Langlois [2] | Surgical complications, component placement, early functional outcomes | Posterolateral approach |
| Biber [26] | Age, sex, lateral (high offset) shaft, surgical approach | Dorsal/posterior approach |
| Abram [27] | Age, gender, cognitive impairment or dementia, side of surgery, surgical approach, implant head size, cementing, operating surgeon grade, assistant grade, intraoperative fracture | Posterior approach, left-side surgery |
| Saberi [4] | Age, sex, medical comorbidities, type of fracture, operation time, intraoperative complications, postoperative length of stay | Posterolateral surgical approach |
| Ames [28] | Age, sex, race, and associated comorbidities, surgeon volume for total hip arthroplasty | Surgeon volume for total hip arthroplasty |
| Enocson [7] | Age, gender, ASA, type of prosthesis | Female |
| Unwin [3] | Surgical approach, grade of surgeon, cemented or not | Posterior approach |
| Keene [29] | Surgical approach, operation time, operative blood loss | Posterior approach |
| Kock [30] | Surgical approach, enhanced soft tissue repair or not | Posterior approach |
FO global femoral offset, LLD leg length discrepancy, ASA American Society of Anaesthesiologists
Table 5.
Strong, moderate, and limited-evidence risk factors of dislocation after hemiarthroplasty
| Level of evidence | Risk factors for dislocation after hemiarthroplasty | Number of participants in high-quality studies | Number of participants in moderate-quality studies | Number of participants in low-quality studies |
|---|---|---|---|---|
| Strong evidence | Posterolateral approach | 102 | 71 | 215 |
| Moderate evidence | Patients with small acetabular coverage | 47 | ||
| Considerable change in postoperative offset of the hip | 35 | |||
| Limited evidence | Decreased postoperative FO, LLD and Wiberg angle | 40 | ||
| Residual length of the femoral neck > 0.5 cm in short patients | 22 | |||
| Delay in surgery of > 24 h | 27 | |||
| Cemented hip hemiarthroplasty | 27 | |||
| Mental disease | 13 | |||
| Small femoral neck | 13 | |||
| Patients with Bateman prostheses and osteonecrosis | 32 | |||
| Left-side surgery | 23 | |||
| Surgeon volume for total hip arthroplasty | 5714 | |||
| Male | 13 | |||
| Female | 21 |
Discussion
Hip HA was listed as the preferred technique by 85% of surgeons from the American Association of Hip and Knee Surgeons for treating displaced femoral neck fractures [10]. The operation for hip HA is an effective technique that enables early rehabilitation and restoration of the ability to perform daily activities. This is particularly important for elderly patients with limited mobility, many of whom have some degree of cognitive impairment. However, dislocation is a potential complication for hip HA that often requires closed or revision reduction, and can cause prolonged immobilisation or even increased mortality rate. A range of studies have investigated the incidence of dislocation following hip HA and potential risk factors. However, the risk factors identified and reported by these studies were mostly inconsistent and the level of evidence supporting individual risk factors was unclear. A systematic review of possible risk factors for dislocation following hip HA that specifically analysed the strength of evidence supporting each of the identified risk factors in the literature was necessary to provide more informative data for surgeons to minimise the risk of dislocation.
By evaluating the 17 studies included in this systematic review, the posterolateral approach was identified as a strong-evidence risk factor for dislocation following hip HA, when posterior capsulotomy is performed for prosthetic insertion [31]. This is logical since the posterolateral approach may break the integrity of the joint capsule and periarticular muscles, and result in insufficient soft tissue coverage for HA. With the aim of allowing faster patient recovery to prevent the deleterious consequences of immobility, this technique is being improved to reduce the risk of dislocation through anatomical reattachment of the short external rotators, as well as preservation and repair of the capsule and smaller anatomical structures [30]. However, the re-attached short external rotators may not provide sufficient stability, causing the suture line to fail postoperatively [3, 28]. If these procedures were not effective, other measures may be used to provide some stability, such as neutral position shoes, lower limb skin traction, and hip casts. In comparison, direct lateral [6] and anterolateral [6] approaches include anatomical repair with re-suturing of the strong tendon of the gluteus medium and/or vastus lateralis, which provides an additional degree of stability. Otherwise, direct anterior approach (DAA) [32], minimally invasive anterolateral approach (MIS-ALA, OCM) [33], and other approaches that maintain anatomical inter-muscular space can be recommended for reducing dislocation risk.
Patients with small acetabular coverage [8, 20] and low postoperative offset [8, 21, 22] as measured from radiographs were identified as two moderate-evidence risk factors for dislocation following hip HA. These factors may lead to poor soft tissue tension, with insufficient coverage of the shallow acetabulum and posterior tissue dysfunction which increase the risk of dislocation [8, 20, 21]. The restoration of global FO and leg length is therefore hindered during the operation. Eleven limited-evidence risk factors were also identified. For instance, a greater residual amount of femoral neck following hip HA increases the risk of dislocation, possibly due to a greater risk of varus positioning of the femoral stem [22]. Male patients had a higher dislocation risk compared to female patients, which may be due to their lower mean centre edge angle of Wiberg [8]. Better comprehension of these identified risk factors and their potential causes will not only help to identify patients with a higher risk of dislocation after hip HA, but will also contribute to the development of prevention strategies. Although the strong-evidence risk factor of posterolateral approach is not likely to be changed by further research, moderate- and low-evidence risk factors and their impacts remain to be proven by ongoing research.
The findings of this study are in alignment with other studies that identified factors affecting the rate of dislocation following hip HA. In one study, falls were found to be a primary mechanism of early dislocation, and the study recommended postoperative fall prevention along with accurate acetabular coverage and hip offset as measures to reduce dislocation rates. Other studies have recommended a direct lateral approach [22] or anterolateral approach [6] for reducing the risk of dislocation, as well as posterior soft tissue repair in patients with neuromuscular disease [24]. A delay in surgery was also identified as an important predictor of dislocation in hip HA [23], and a shorter preoperative time (not exceeding 48 h) is recommended [20].
This study has a number of limitations. First, the criteria used in this study for methodological quality assessment and evidence synthesis have been adopted by other systematic reviews, but the choice of these analysis techniques remain controversial [16–18, 34]. Publication bias and significant results preferred by authors were acquired by multivariable analysis. Potential bias also exists in patient selection, particularly for mono-centric studies. Second, the heterogeneity of study characteristics must be considered for the included studies. For instance, differences in the length of follow-up among studies may have led to varying incidences of dislocations. The facilities available at different institutes and experience of different surgeons within individual publications were inconsistent. These heterogeneities indirectly affected the classification of study quality and evidence synthesis [17, 18]. The predicted quality and strength of evidence for the risk factors identified in this study may therefore have been overestimated or underestimated.
Overall, our study provides a systematic review that informs surgeons on the most important risk factors for dislocation following hip HA based on the current evidence. Surgical strategies that may help reduce the risk of dislocation include abandoning the posterolateral approach and using the anterior, direct lateral, or anterolateral approaches during surgery, as well as maintaining appropriate acetabular coverage and hip offset. Dissemination of the outcomes of this study will contribute to directing research towards identified risk factors that need backing by stronger evidence to become useful recommendations for clinical guidelines.
Conclusion
The current literature presents strong evidence for posterolateral surgical approach as a risk factor for dislocation for patients who have undergone hip hemiarthroplasty. Other risk factors were identified in this study that were supported by moderate or low evidence, and their impacts require clarification through further high-quality studies such as prospective case–control studies. This systematic review provides evidence in helping surgeons develop optimal prevention strategies for postoperative dislocation in hip hemiarthroplasty.
Electronic supplementary material
Below is the link to the electronic supplementary material.
Acknowledgements
We greatly thank Xiuxiu Wang from Taiyuan University of Technology for the excellent work of diagram.
Funding
This study was supported by National Natural Science Foundation of China (Grant No. 81802204), Second Hospital of Shanxi Medical University Doctor’s Funds (No. 2017-105), the Natural Science Foundation of Shanxi Province (Grant No. 201801D221117), the Program for the Outstanding Innovative Teams of Higher Learning Institutions of Shanxi (2019L0410). Australian National Health and Medical Research Council (APP1120246)
Compliance with Ethical Standards
Conflict of Interest
The authors declare that they have no conflict of interest.
Ethical Standard Statement
This study has been performed in accordance with the ethical standards and was approved by the Ethics Committee of the Shanxi Medical University. The Ethical Number was 2018LL036.
Informed Consent
For this type of study informed consent is not required.
Footnotes
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Bin Wang and Haifeng Liu contributed equally to this work.
References
- 1.Bhandari M, Devereaux PJ, Tornetta P, 3rd, et al. Operative management of displaced femoral neck fractures in elderly patients. An international survey. The Journal of Bone and Joint Surgery American. 2005;87:2122–2130. doi: 10.2106/00004623-200509000-00027. [DOI] [PubMed] [Google Scholar]
- 2.Langlois J, Delambre J, Klouche S, et al. Direct anterior Hueter approach is a safe and effective approach to perform a bipolar hemiarthroplasty for femoral neck fracture: outcome in 82 patients. Acta Orthopaedica. 2015;86:358–362. doi: 10.3109/17453674.2014.1002987. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 3.Unwin AJ, Thomas M. Dislocation after hemiarthroplasty of the hip: a comparison of the dislocation rate after posterior and lateral approaches to the hip. Annals of the Royal College of Surgeons of England. 1994;76:327–329. [PMC free article] [PubMed] [Google Scholar]
- 4.Saberi S, Arabzadeh A, Khomeisi B, et al. Early complications following bipolar hemiarthroplasty for femoral neck fracture in elderly patients. Academic Journal of Surgery. 2014;1:45–48. [Google Scholar]
- 5.Poignard A, Bouhou M, Pidet O, et al. High dislocation cumulative risk in THA versus hemiarthroplasty for fractures. Clinical Orthopaedics and Related Research. 2011;469:3148–3153. doi: 10.1007/s11999-011-1987-7. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 6.Enocson A, Tidermark J, Tornkvist H, et al. Dislocation of hemiarthroplasty after femoral neck fracture: better outcome after the anterolateral approach in a prospective cohort study on 739 consecutive hips. Acta Orthopaedica. 2008;79:211–217. doi: 10.1080/17453670710014996. [DOI] [PubMed] [Google Scholar]
- 7.Enocson A, Pettersson H, Ponzer S, et al. Quality of life after dislocation of hip arthroplasty: a prospective cohort study on 319 patients with femoral neck fractures with a one-year follow-up. Quality of Life Research. 2009;18:1177–1184. doi: 10.1007/s11136-009-9531-x. [DOI] [PubMed] [Google Scholar]
- 8.Ninh CC, Sethi A, Hatahet M, et al. Hip dislocation after modular unipolar hemiarthroplasty. The Journal of Arthroplasty. 2009;24:768–774. doi: 10.1016/j.arth.2008.02.019. [DOI] [PubMed] [Google Scholar]
- 9.Sanchez-Sotelo J, Haidukewych GJ, Boberg CJ. Hospital cost of dislocation after primary total hip arthroplasty. The Journal of Bone and Joint Surgery American. 2006;88:290–294. doi: 10.2106/00004623-200602000-00006. [DOI] [PubMed] [Google Scholar]
- 10.Iorio R, Davis CM, 3rd, Healy WL, et al. Impact of the economic downturn on adult reconstruction surgery: a survey of the American Association of Hip and Knee Surgeons. The Journal of Arthroplasty. 2010;25:1005–1014. doi: 10.1016/j.arth.2010.08.009. [DOI] [PubMed] [Google Scholar]
- 11.Khan KS, Kunz R, Kleijnen J, et al. Five steps to conducting a systematic review. Journal of the Royal Society of Medicine. 2003;96:118–121. doi: 10.1177/014107680309600304. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 12.Ma X, Xing D, Ma J, et al. Risk factors for new vertebral compression fractures after percutaneous vertebroplasty: qualitative evidence synthesized from a systematic review. Spine. 2013;38:E713–722. doi: 10.1097/BRS.0b013e31828cf15b. [DOI] [PubMed] [Google Scholar]
- 13.Moher D, Liberati A, Tetzlaff J, et al. Preferred reporting items for systematic reviews and meta-analyses: the PRISMA statement. PLoS Medicine. 2009;6:e1000097. doi: 10.1371/journal.pmed.1000097. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 14.Knobloch K, Yoon U, Vogt PM. Preferred reporting items for systematic reviews and meta-analyses (PRISMA) statement and publication bias. Journal of Cranio-Maxillo-Facial Surgery. 2011;39:91–92. doi: 10.1016/j.jcms.2010.11.001. [DOI] [PubMed] [Google Scholar]
- 15.Duckitt K, Harrington D. Risk factors for pre-eclampsia at antenatal booking: Systematic review of controlled studies. BMJ (Clinical Research Ed) 2005;330:565. doi: 10.1136/bmj.38380.674340.E0. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 16.Gomes B, Higginson IJ. Factors influencing death at home in terminally ill patients with cancer: Systematic review. BMJ (Clinical Research Ed) 2006;332:515–521. doi: 10.1136/bmj.38740.614954.55. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 17.Urquhart DM, Hanna FS, Brennan SL, et al. Incidence and risk factors for deep surgical site infection after primary total hip arthroplasty: A systematic review. The Journal of Arthroplasty. 2010;25(1216–1222):e1211–1213. doi: 10.1016/j.arth.2009.08.011. [DOI] [PubMed] [Google Scholar]
- 18.Lievense AM, Bierma-Zeinstra SM, Verhagen AP, et al. Influence of obesity on the development of osteoarthritis of the hip: a systematic review. Rheumatology (Oxford) 2002;41:1155–1162. doi: 10.1093/rheumatology/41.10.1155. [DOI] [PubMed] [Google Scholar]
- 19.West S, King V, Carey TS, et al. Systems to rate the strength of scientific evidence. Evidence Report/Technology Assessment. 2002;47(Summ):1–11. [PMC free article] [PubMed] [Google Scholar]
- 20.Madanat R, Makinen TJ, Ovaska MT, et al. Dislocation of hip hemiarthroplasty following posterolateral surgical approach: a nested case-control study. International Orthopaedics. 2012;36:935–940. doi: 10.1007/s00264-011-1353-0. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 21.Mukka S, Lindqvist J, Peyda S, et al. Dislocation of bipolar hip hemiarthroplasty through a postero-lateral approach for femoral neck fractures: A cohort study. International Orthopaedics. 2015;39:1277–1282. doi: 10.1007/s00264-014-2642-1. [DOI] [PubMed] [Google Scholar]
- 22.Pajarinen J, Savolainen V, Tulikoura I, et al. Factors predisposing to dislocation of the Thompson hemiarthroplasty: 22 dislocations in 338 patients. Acta Orthopaedica Scandinavica. 2003;74:45–48. doi: 10.1080/00016470310013644. [DOI] [PubMed] [Google Scholar]
- 23.Salem KM, Shannak OA, Scammell BE, et al. Predictors and outcomes of treatment in hip hemiarthroplasty dislocation. Annals of the Royal College of Surgeons of England. 2014;96:446–451. doi: 10.1308/003588414X13946184903045. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 24.Suh KT, Kim DW, Lee HS, et al. Is the dislocation rate higher after bipolar hemiarthroplasty in patients with neuromuscular diseases? Clinical Orthopaedics and Related Research. 2012;470:1158–1164. doi: 10.1007/s11999-011-2139-9. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 25.Sierra RJ, Schleck CD, Cabanela ME. Dislocation of bipolar hemiarthroplasty: rate, contributing factors, and outcome. Clinical Orthopaedics and Related Research. 2006;442:230–238. doi: 10.1097/01.blo.0000183741.96610.c3. [DOI] [PubMed] [Google Scholar]
- 26.Biber R, Brem M, Singler K, et al. Dorsal versus transgluteal approach for hip hemiarthroplasty: An analysis of early complications in seven hundred and four consecutive cases. International Orthopaedics. 2012;36:2219–2223. doi: 10.1007/s00264-012-1624-4. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 27.Abram SG, Murray JB. Outcomes of 807 Thompson hip hemiarthroplasty procedures and the effect of surgical approach on dislocation rates. Injury. 2015;46:1013–1017. doi: 10.1016/j.injury.2014.12.016. [DOI] [PubMed] [Google Scholar]
- 28.Ames JB, Lurie JD, Tomek IM, et al. Does surgeon volume for total hip arthroplasty affect outcomes after hemiarthroplasty for femoral neck fracture? American Journal of Orthopedics (Belle Mead, NJ) 2010;39:E84–89. [PubMed] [Google Scholar]
- 29.Keene GS, Parker MJ. Hemiarthroplasty of the hip–the anterior or posterior approach? A comparison of surgical approaches. Injury. 1993;24:611–613. doi: 10.1016/0020-1383(93)90125-P. [DOI] [PubMed] [Google Scholar]
- 30.Ko CK, Law SW, Chiu KH. Enhanced soft tissue repair using locking loop stitch after posterior approach for hip hemiarthroplasty. The Journal of Arthroplasty. 2001;16:207–211. doi: 10.1054/arth.2001.20539. [DOI] [PubMed] [Google Scholar]
- 31.Bush JB, Wilson MR. Dislocation after hip hemiarthroplasty: anterior versus posterior capsular approach. Orthopedics. 2007;30:138–144. doi: 10.3928/01477447-20070201-05. [DOI] [PubMed] [Google Scholar]
- 32.Kunkel ST, Sabatino MJ, Kang R, et al. A systematic review and meta-analysis of the direct anterior approach for hemiarthroplasty for femoral neck fracture. European Journal of Orthopaedic Surgery and Traumatology. 2018;28:217–232. doi: 10.1007/s00590-017-2033-6. [DOI] [PubMed] [Google Scholar]
- 33.de Jong L, Klem T, Kuijper TM, et al. The minimally invasive anterolateral approach versus the traditional anterolateral approach (Watson-Jones) for hip hemiarthroplasty after a femoral neck fracture: an analysis of clinical outcomes. International Orthopaedics. 2018;42:1943–1948. doi: 10.1007/s00264-017-3756-z. [DOI] [PubMed] [Google Scholar]
- 34.Battle CE, Hutchings H, Evans PA. Risk factors that predict mortality in patients with blunt chest wall trauma: A systematic review and meta-analysis. Injury. 2012;43:8–17. doi: 10.1016/j.injury.2011.01.004. [DOI] [PubMed] [Google Scholar]
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