Fracture fixation versus hemiarthroplasty for unstable intertrochanteric fractures in elderly patients: A systematic review and network meta-analysis of randomized controlled trials

Is there a femoral morphology at risk of a cervical or pertrochanteric fracture? Description and validation of the "Neck shaft ratio" and the "Intertrochanteric distal ratio" after analyzing a continuous cohort of 126 bilateral fractures of the proximal femur

BACKGROUND

Proximal femur fractures constitute a public health concern given their high frequency and the aging population. The frequency of a contralateral fracture occurring can reach up to 15% of cases. Certain historical or demographic factors constitute risk factors for refracture, but the type of fracture, either of the femoral neck (FN) or pertrochanteric (PT), cannot be predicted. The objectives of this retrospective study were: firstly, to analyze several anatomical markers in order to determine whether they predispose to a certain type of fracture in the event of contralateral refracture, and secondly, to determine the predictive power of these possible radiological markers for the type of contralateral fracture.

HYPOTHESIS

The hypothesis was that the "Neck shaft ratio" (NSR) and the "Intertrochanteric distal ratio" (ITDR) made it possible to determine a proximal femoral morphology at risk of FN and/or PT fracture in the event of a second fracture.

MATERIAL AND METHODS

This continuous retrospective single-center series from January 2011 to December 2019 of patients who presented with bilateral fractures of the proximal femurs was analyzed. Radiographs, taken after the first fracture, of the contralateral femur were studied. Morphological measurements previously described in the literature were carried out as well as the NSR (ratio of the medial cortical thicknesses of the femoral neck at its narrowest and basicervical level) and the ITDR (ratio of the medial diaphyseal cortical thicknesses at 5mm and 20mm from the distal portion of the lesser trochanter). One hundred and twenty-six patients were included: 46/126 (36.5%) had bilateral FN, 50/126 (39.7%) bilateral PT and 30/126 (23.8%) one of each.

RESULTS

Only NSR and ITDR were significant predictive measures for FN or PT fracture type [0.54±0.11 vs. 0.81±0.16 (p<0.0001) and 0. 85±0.1 vs. 0.68±0.1 (p<0.0001), respectively]. These two ratios had an excellent predictive value for the type of fracture occurring on the contralateral side [NSR: AUC ROC = 0.91 (95% CI; 0.86-0.96); ITDR: AUC ROC = 0.81 (95% CI; %, 0.74-0.89)]. The NSR had excellent intra- and inter-observer reproducibility with an interclass correlation coefficient of 0.93 [95% CI: 0.86-0.97] and 0.91 [95% CI: 0.82-0.96] respectively, the same also applied for the ITDR with interclass correlation coefficient values of 0.93 [95% CI: 0.87-0.97] and 0.86 [95% CI: 0.73-0.93] respectively.

DISCUSSION

The NSR and ITDR ratios offer a simple and reproducible means to predict a morphological predisposition to a certain fracture type, respectively an FN and PT on the side contralateral to an initial osteoporotic proximal femur fracture. A prospective cohort study would be useful in defining a possible prognostic nature on the occurrence and/or time until refracture.

LEVEL OF EVIDENCE

III; retrospective control case.

A Novel Internal Fixation Design for the Treatment of AO/OTA-31A3.3 Intertrochanteric Fractures: Finite Element Analysis

OBJECTIVE

AO/OTA 31-A3.3 intertrochanteric fracture is the most unstable type of intertrochanteric fracture, with a high rate of postoperative complications and implant failure. We have designed a new intramedullary fixation, proximal femoral totally bionic nail (PFTBN), for the treatment of A3.3 intertrochanteric fracture. To test its biomechanical performance, we adopted the method of finite element analysis and compared PFTBN with proximal femoral nail antirotation (PFNA) and proximal femoral bionic nail (PFBN, another internal fixation we previously designed for stable intertrochanteric fractures).

METHODS

Mimics, 3-matic, ANSYS, and other software were used to construct a highly precise and realistic 3D digital model of the human femur. An AO/OTA 31-A3.3 intertrochanteric fracture of the femur was constructed according to the 2018 classification of AO/OTA, and then assembled with PFNA, PFBN and PFTBN models, respectively. The stress distribution and displacement distribution of the three groups of constructs were tested under three times the body weight load and one-foot standing configuration.

RESULTS

In terms of maximum stress and maximum displacement, the PFTBN group outperforms the PFBN group, and the PFBN group, in turn, surpasses the PFNA group. The maximum stress of PFTBN group was 408.5 Mpa, that of PFBN group was 525.4 MPa, and that of PFNA group was 764.3 Mpa. Comparatively, the maximum stress in the PFTBN group was reduced by 46.6% when contrasted with the PFNA group. Moreover, the stress dispersion within the PFTBN group was more evenly distributed than PFNA group. Regarding maximum displacement, the PFTBN group displayed the least displacement at 5.15 mm, followed by the PFBN group at 7.32 mm, and the PFNA group at 7.73 mm. Notably, the maximum displacement of the PFTBN group was 33.4% less than that observed in the PFNA group. Additionally, the relative displacement between the fragment and implant at the tip of pressure screw or helical blade was 0.22 mm in the PFTBN group, 0.34 mm in the PFBN group, and substantially higher 0.51 mm in the PFNA group.

CONCLUSION

The "lever-reconstruction-balance" theory provides a new perspective for us to understand the mechanical conduction of the proximal femur. Compared with PFNA, in treating A3.3 intertrochanteric fractures PFTBN can better reconstruct the function of lateral wall, restore physiological mechanical conduction, increase postoperative stability, and finally reduce the risk of postoperative cut-out and implant failure. It might be a better alternative for the treatment of A3.3 intertrochanteric fracture.

Intertrochanteric (Reverse Oblique) Fracture Subclassifications AO/OTA 31-A3 Have No Effect on Outcomes or Postoperative Complications

Background

Reverse oblique intertrochanteric fractures (ROFs) are unstable extracapsular hip fractures that present a mechanical challenge. These fractures are classified as AO/Orthopaedic Trauma Association (OTA) 31-A3 according to the Trauma Association classification system and can further be subclassified into 3 subtypes based on their specific characteristics. The study aimed to evaluate and compare the radiographic and clinical outcomes of the 3 subtypes of ROFs.

Methods

A retrospective study was conducted at a single high-volume, tertiary center, where data were collected from electronic medical records of consecutive patients who underwent surgical fixation of AO/OTA 31-A3 fractures. Patients with less than 1-year follow-up, pathological fractures, and revision surgery were excluded. The subtypes of fractures were classified as 31-A3.1 (simple oblique), 31-A3.2 (simple transverse), and 31-A3.3 (wedge or multi-fragmentary). The operation was done using 4 different fixation methods, and radiological evaluation was performed at routine intervals.

Results

The final population consisted of 265 patients (60.8% women) with a mean age of 77.4 years (range, 50-100 years) and the mean follow-up time was 35 months (range, 12-116 months). The incidence of medical complications was similar across the groups. However, there was a trend toward a higher incidence of orthopedic complications and revision rates in the 31-A3.2 group, although this was not statistically significant (p = 0.21 and p = 0.14, respectively).

Conclusions

Based on the findings of this study, no significant differences were observed between the groups, indicating that the subclassifications of AO/OTA 31-A3 fractures do not have a significant impact on surgical outcomes or the occurrence of postoperative complications.

Cemented bipolar hemiarthroplasty for unstable intertrochanteric fracture in elderly patients over 70 years: Boon or bane?

INTRODUCTION

The surgical management of intertrochanter femur fracture in elderly patient is still under debate. Various implants can be utilised but prosthetic replacement is gaining popularity. This study was performed to evaluate the functional and clinical outcomes of cemented bipolar arthroplasty as a primary treatment for unstable intertrochanteric fracture in elderly patients (> 70 years).

MATERIALS AND METHODS

Thirty-seven patients with unstable intertrochanteric fracture in elderly patient (> 70 years) who underwent cemented bipolar hemiarthroplasty. Intra-operative and post-operative complications were noted; functional outcomes were assessed using Harris hip score (HHS). All patients were followed up for a minimum of 12 months.

RESULTS

Overall 90% of patients has some minor or major intra or post-operative complication. One year mortality rate was 16% (6/37). Cardiopulmonary events were the most common life threatening incident. Mean fall in Haemoglobin was 1.6 gm/dL. The average time for full weight bearing mobilisation with the help of walker was 2.8 ± 1.2 days (1-8 days). The average duration of surgery was 58 ± 6 min (44-96 min) with an average blood loss of 126 ± 24 mL (90-380 mL). HHS at the end of 12 months was 77.

CONCLUSIONS

The use of bipolar hemiarthroplasty in senile patient with unstable hemiarthroplasty gives an advantage of early weight bearing. However, it is associated with risk of significant intra or post-operative morbidity due to intra-operative trauma, surgical time and blood loss during the surgery. Although hemiarthroplasty can be a single-time solution to the complexities of intertrochanter fracture in elderly patients but should be performed in selected patients only.

Should trochanteric fractures in elderly patients be treated by arthroplasty or internal fixation?

Most trochanteric fractures are treated by fixation, most often intramedullary. Nevertheless, the desire to have patients walk as soon as possible and the fear of fixation failure has driven some surgeons to carry out an arthroplasty instead, especially for unstable fractures and/or in patients with severe osteoporosis, in order to avoid the difficult conversion to arthroplasty later on if the fixation fails. The aim of this review was to specify the role, technique and results of performing arthroplasty in this context. In which fractures? Unstable fractures (A2.2, A2.3 and A3), especially in osteoporotic bone, which are the most difficult to reduce and fix, and in cases with associated osteoarthritis. For which patients? Arthroplasty should not be done in patients who have ASA≤3 due to greater blood loss and longer operative time. Since the postoperative Parker score often drops, arthroplasty should not be done in patients having a Parker score<6. What are the technical problems? Arthroplasty must be done by an experienced surgeon because of the lack of anatomical landmarks, although fracture fixation has its own demands (satisfactory reduction, appropriate length and position of cervicocephalic screw). What are the results and complications? Despite several comparative studies (randomized trials, meta-analysis and prospective studies), it is difficult to draw any conclusions. These studies show worse performance of dynamic hip screws relative to intramedullary nails. The complication and revision rates were higher for nails than arthroplasty, but not in every study, while the functional outcomes with nails (with or without immediate weightbearing) were better than those of arthroplasty beyond 6 months. What is the mortality rate? It was lower after nailing in a few studies but was mainly determined by the patient's comorbidities and preoperative Parker score. The best indication for arthroplasty may be self-sufficient patients over 70 years of age who have an unstable fracture with severe osteoporosis. Nevertheless, new studies should be done to compare arthroplasty to nailing with immediate return to weightbearing in patients having the same type of fracture, defined using 3D CT scan. Level of evidence: Expert advice.

Complication Rates and Survival of Nonagenarians after Hip Hemiarthroplasty versus Proximal Femoral Nail Antirotation for Intertrochanteric Fractures: A 15-Year Retrospective Cohort Study of 113 Cases

OBJECTIVE

Intertrochanteric fracture is a very common but serious type of hip fracture in nonagenarians. The surgical treatment remains a significant challenge for orthopedists. The objective of this study was to investigate postoperative complications and survival outcomes compared between bipolar hemiarthroplasty (HA) and proximal femoral nail anti-rotation (PFNA) in nonagenarians with intertrochanteric fractures, and to evaluate the efficacy and safety of the two surgical procedures in this patient population.

METHODS

A total of 113 consecutive nonagenarians who underwent bipolar HA or PFNA for the treatment of intertrochanteric fractures from January 2006 to August 2021 were retrospectively studied in the current paper. There were 34 males and 79 females, with a mean age of 92.2 years (range 90-101 years) at the time of operation. The average duration of follow-up was 29.7 months (range 1-120 months). The full cohort was divided into bipolar HA (77 cases) and PFNA (36 cases) groups. Damage control orthopedics was used to determine the optimal surgery time and assist in perioperative management. A restrictive blood transfusion strategy was employed, along with appropriate adjustments under multidisciplinary assessment, throughout the perioperative period. Perioperative clinical information and prognostic data were analyzed. Kaplan-Meier survival curves were used for survival analysis, and landmark analysis divided the entire follow-up period into 1-12 months (short-term), 13-42 months (medium-term) and 43-120 months (long-term) according to the configurations of Kaplan-Meier survival curves.

RESULTS

Both groups had similar general variables except for the proportion of high adjusted Charlson comorbidity index (aCCI) (≥6 points) (6.5% in bipolar HA group and 22.2% in PFNA group, p = 0.024). Intraoperative blood loss and transfusion requirements were greater, and the intraoperative transfusion rates were higher in the bipolar HA group compared to the PFNA group (all p < 0.05). The complications rates, 1- to 60-month cumulative all-cause mortality, postoperative optimal Harris hip score (HHS), and Barthel index (BI) presented no significant difference between the two groups (all p > 0.05). Both groups had similar overall survival curves (p = 0.37). However, landmark analysis revealed that bipolar HA group exhibited higher survival rates in medium-term (p = 0.01), while similar survival rates were observed in the short- and long-term post-operation periods (both p > 0.05). Cox regression with survival-time-dependent covariate calculated the hazard ratio (HR) of bipolar HA was 0.41 in medium-term (p = 0.039).

CONCLUSION

Bipolar HA is equally effective and reliable as PFNA for treating intertrochanteric fractures in nonagenarians. Despite resulting in more intraoperative blood loss and transfusions, bipolar HA therapy is associated with a higher medium-term survival rate compared to PFNA treatment. The application of damage control orthopedics and precise perioperative patient blood management could contribute to the positive clinical outcomes observed in this patient population.

Functional Outcome of Hemiarthroplasty of the Hip for Unstable Intertrochanteric Fractures of the Femur in Elderly Patients: A Prospective Study

Introduction It is frequently challenging to treat an unstable intertrochanteric fracture in elderly people by internal fixation because of difficult anatomical reduction, poor bone quality, the need for prolonged bed rest and restricted ambulation. As an alternative to internal fixation, cemented bipolar hemiarthroplasty has been used as a treatment for unstable intertrochanteric fractures to avoid the postoperative immobilization-related complications. The aim of this study was to evaluate the functional and clinical outcomes of primary cemented bipolar hemiarthroplasty for elderly patients with unstable intertrochanteric fractures. Methodology A prospective study was conducted that included 30 patients who were admitted to the apex trauma center at a tertiary care center from January 2019 to August 2020 with unstable intertrochanteric fractures (Association for Osteosynthesis/Orthopaedic Trauma Association, or AO/OTA, types 31-A2.2 and 31-A2.3); patients treated with cemented bipolar hemiarthroplasty, with at least one year of follow-up were included in the study. Basic descriptive statistics were used and the results were presented in frequencies, percentages for categorical variables and means and standard deviations for continuous variables. Results According to the Harris Hip Score, at the end of 12 months, 9 patients (30%) had excellent results, 14 patients (46.67%) had good results, 5 patients (16.67) had fair results, and 2 cases (6.67) had poor results. With cemented hemiarthroplasty, 87.7% of older patients with unstable intertrochanteric fractures were able to walk sooner, and the results were good. Conclusion Hemiarthroplasty of the hip with a cemented bipolar prosthesis appears to be a reliable treatment method for the management of unstable intertrochanteric fractures in elderly patients with osteoporosis; it allows for early ambulation and leads to a favorable functional outcome in most patients following surgery.

What Is the Best Treatment Choice for Concomitant Ipsilateral Femoral Neck and Intertrochanteric Fracture? A Retrospective Comparative Analysis of 115 Consecutive Patients

PURPOSE

Although a concomitant ipsilateral femoral neck and intertrochanteric fracture has been considered to be a rare type of injury, its incidence has been increasing, especially among elderly hip fracture patients. However, there is limited evidence on the optimal treatment option. This study surveys surgical outcomes of different implants in order to assist in selecting the best possible implant for a combined femoral neck and intertrochanteric fracture.

METHODS

The postoperative complications after the treatment of a concomitant ipsilateral femoral neck and intertrochanteric fracture via cephalomedullary nail (CMN), dynamic hip screw (DHS), and hip arthroplasty groups were analyzed by retrospectively reviewing the electronic medical records of 115 consecutive patients.

RESULTS

The patient demographics and perioperative details showed no significant discrepancies amongst different surgical groups, except for the operative time; a CMN had the shortest mean operative time (standard deviation) of 85.6 min (31.1), followed by 94.7 min (22.3) during a DHS, and 107.3 min (37.2) during an HR (p = 0.021). Of the 84 osteosynthesis patients, 77 (91.7%) achieved a fracture union. Only one (3.2%) of the 31 HR cases had a dislocation. The sub-analysis of the different osteosynthesis methods showed a higher incidence of excessive sliding and the nonunion of the fracture fragment in the DHS group than that in the CMN group (p = 0.004 and p = 0.022, respectively). The different surgical methods did not significantly vary in other outcome variables, such as the re-operation rate, mortality, and hip function.

CONCLUSIONS

For the surgical treatment of combined femoral neck and trochanteric fractures, osteosynthesis did not differ significantly from an HR in terms of the overall postoperative complications, reoperation and mortality rate, and hip function, however, the risk of nonunion and more mechanical complications should be considered when choosing a DHS. Our suggestion for the treatment of a femoral neck and ipsilateral trochanteric fracture is that a surgeon should choose wisely between an HR and a CMN depending on the patient's age, the displacement of the femoral neck, and one's expertise.

Functional outcome of conversion total hip arthroplasty (CTHA) using uncemented distally loading femoral stem for failed fixation of proximal femoral nail - A case series

Introduction and aims

There is paucity of prospective studies on conversion total hip arthroplasty (CTHA) for failed proximal femoral nailing. The objective of this study is to evaluate the functional outcome of CTHA using extensively porous coated distal loading stem for failed proximal femoral nailing.

Patients and methods

Fifteen consecutively operated patients for failed proximal femoral nail treated with single stage procedure of nail extraction and CTHA were included in this prospective observational study. All patients received metal-on-polyethylene bearing with uncemented press-fit acetabular cup (Pinnacle cup; DePuy, Warsaw [IN], USA) and extensively porous coated distally loading revision stem (Solution stem; DePuy, Warsaw [IN], USA). All patients were assessed preoperatively and postoperatively at one, three, six and more than twelve months using the Harris Hip Score (HHS). The responsiveness of HHS was assessed using Effect Size (ES) and Standardised Response Mean (SRM). ES and SRM >0.8 indicates adequate responsiveness.

Results

The mean duration of follow-up was 16.9 months for the overall cohort (SD: 7.9; range: 6-28 months). The mean preoperative HHS was 32 ± 6.1, the mean HHS at six months follow-up was 89.7 ± 4.0 and the mean HHS at final follow-up of atleast one year was 93.7 ± 3.0. There was a statistically and clinically significant improvement in the HHS from preoperatively to final follow-up postoperatively (p < 0.0001). At the final follow-up, twelve patients (80%) had an excellent outcome and three patients (20%) had a good outcome as per HHS grading. The ES was 9.87 and the SRM was 8.86 thereby suggesting adequate responsiveness. One patient developed surgical site infection and another patient developed dislocation. Both were successfully treated and subsequently the patients made uneventful recovery. None of the patients required revision surgery.

Conclusion

HHS has adequate responsiveness for assessing the functional outcome of CTHA. We recommend the use of an uncemented cup and uncemented extensively porous coated, distal loading stem for failed PFN fixation in intertrochanteric hip fractures.

Reduction with Pre-Drilling Combined with a Finger Reduction Tool in Difficult-to-Reduce Intertrochanteric Fracture

Objective

To investigate the feasibility of pre‐drilling combined with a finger reduction tool for the reduction of difficult‐to‐reduce intertrochanteric fractures.

Methods

Patients diagnosed with complicated intertrochanteric fractures during the period from July 2016 to May 2021 at the Affiliated Hospital of our College were enrolled in this study. All patients underwent reduction by pre‐drilling combined with a finger reduction tool followed by fixing with proximal femoral nail antirotation. The outcome of reduction was evaluated by intraoperative fluoroscopy. The operation time, intraoperative fluoroscopy frequency, and incidence of postoperative complications (including infection in the incision area, coxa vara, nail withdrawal, nail breakage, blade cut‐out, lower limb vein thrombosis, and pulmonary embolism) were recorded to evaluate the speed of the operation, the difficulty of the operation, and the prognosis of the patient, respectively. The Harris hip score at 9 months after surgery was used to evaluate the hip recovery.

Results

A total of 52 patients (17 men and 35 women), 61–88 (77.54 ± 7.40) years of age were included in the study. There were 14 patients with cardiovascular or cerebrovascular disease, ten patients with diabetes, three patients with Parkinson's disease, and three patients with respiratory diseases. The fractures included in the study were classified according to the Orthopedic Trauma Association 31 classification system as type A2.2 (n = 36) or type A2.3 (n = 16). The time from injury to surgery was 1–11 (3.35 ± 1.78) days, and the operation time ranged 31–101 (65.67 ± 14.17) min. The intraoperative blood loss ranged from 40 to 100 (67.69 ± 18.24) mL, and the number of intraoperative fluoroscopy images obtained was 12 to 32 (20.42 ± 5.27). The Harris hip score at 9 months after surgery ranged from 84 to 94 (90.06 ± 2.15). Patients were followed for 9–16 (10.63 ± 1.61) months. One patient died of acute myocardial infarction at 9 months after surgery. One patient suffered from nail withdrawal 5 months post‐operation and thus underwent hemiarthroplasty.

Conclusions

Satisfactory reduction can be achieved using a pre‐drilling femoral trochanter combined with a finger reduction tool for the management of difficult‐to‐reduce complex intertrochanteric fractures. This technique does not increase surgical trauma and also reduces the dose of radiation administered to the patient.

Distal fixation modular stem hemiarthroplasty versus proximal femoral nailing for unstable intertrochanteric fractures: a retrospective cohort study

The treatment of unstable intertrochanteric fractures (UITF) is a controversial issue in the current literature. The aim of this study was to compare the curative effects of distal fixation modular stem (DFMS) hemiarthroplasty with proximal femoral nailing (PFN) on UITFs in the elderly. From February 2017 to November 2019, 98 elderly (≥65 years) patients with UITF were included in this single-center retrospective cohort study. Mean follow-up duration was 24.1±11.9 months. Patients were divided into the DFMS group (52 patients) and the PFN group (46 patients). In the DFMS group, trochanteric fixation was performed using a trochanteric cable plate system. Primary outcome measures included Harris hip score (HHS), mobility score, implant related complications and mortality. Secondary outcome measures included hospitalization duration, surgical time and transfusion rate. Mean age of the patients was 78.7±7.2 years (65-96 years). DFMS group had longer surgical time, higher transfusion rates and longer hospital stays (p<0.05). Mean HHS was 80.7±10.5 and 81.9±12.2 in the DFMS group and PFN group, respectively. There was no statistically significant difference between the two groups in terms of HHS, mobility score and mortality. Implant failure rates were significantly higher in the PFN group (p=0.015). Implant failure, one year mortality and overall mortality rates were 0%, 15.4% and 17.3% in DFMS group and 10.9%, 15.2% and 19.5% in PFN group, respectively. Both surgical methods can be effectively used in the treatment of UITFs with similar satisfactory functional results and similar mortality rates. In addition, the DFMS group exhibited significantly lower implant failure rates and PFN group provided significantly lower surgical time duration, transfusion rate and hospital stay duration.

Treatment of Intertrochanteric Femur Fractures with Hip Arthroplasty in Older Patients: A Narrative Review of Indications and Outcomes

Intertrochanteric femur fractures are common in older patients and often have a significant impact on disability. The treatment aims to achieve a rapid return to the prior functional level with a low rate of complications and mortality. Surgical management by internal fixation is the mainstay of treatment for most of these fractures. Even when treated with intramedullary nails, the overall complication rates are high, especially for unstable or highly comminuted fractures or in the presence of poor bone quality. Hip arthroplasty is an alternative in older patients with intertrochanteric femur fractures at high risk of fixation failure or with concomitant intraarticular pathologies. Especially patients whose condition precludes prolonged bedrest and who are at risk of significant deterioration if their locomotor function cannot be restored rapidly are likely to benefit from hip arthroplasty. The choice of the surgical technique mainly depends on the surgeon’s preferences and the fracture characteristics. Bipolar hemiarthroplasty is the most common type of prosthesis used with primary or revision femoral stems. Compared with intramedullary nails, hip arthroplasty has a better early functional outcome and lower rates of surgical complications as well as reoperations. However, the functional outcome and the mortality rate in the longer term tend to favor intramedullary nails, even though the results are inconsistent, and a statistically significant difference cannot always be obtained. Currently, there are no guidelines that define the role of hip arthroplasty in the treatment of intertrochanteric femur fractures in older patients. The literature only offers an overview of the possibilities of the usage of hip arthroplasty, but methodological limitations are common, and evidence levels are low. Further studies are needed to identify the intertrochanteric fractures that are at high risk of internal fixation failure, the characteristics that determine which patients may benefit most from hip arthroplasty, and the optimal surgical technique.