***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    Input: Introduction There were higher rates of revision , complication , non-union , delayed union , and poorer functional outcomes reported in super-aged patients of undisplaced femoral neck fractures treated with internal fixation . Therefore , we design ed this r and omized comparative study aim ing to compare the effectiveness and long-term follow-up results of hemiarthroplasty ( HA ) with that of multiple cannulated screws ( MCS ) . Material s and methods Eligible participants were r and omly assigned into two groups for different methods of operation ( hemiarthroplasty group and internal fixation group ) . The related indexes and data of two groups were collected for comparative analysis during the average follow-up period of 38.68 ± 28.24 months . Results There were only two patients performed reoperation in HA group , and the reoperation rate of HA group ( 5.41 % , 2/37 ) was significantly lower than that of IF group ( 21.4 % , 9/41 ) ( P value = 0.000 ) . The comparison of survival curves for reoperation showed significant differences between two groups ( P value = 0.031).The results of Cox proportional hazards model suggested that only operation method significantly affected the occurrence of reoperation ( P value = 0.049 ) . The results of survival analysis showed that there was no significant difference in survival time between two groups ( P value = 0.682 ) . And in the Cox proportional hazards model , only age significantly affected the occurrence of death ( P value = 0.000 ) . The average Harris scores of two groups were all above 75 points , and there was no significant difference in Harris scores between the two groups ( P value greater than 0.05 ) . But in the early term follow-up , the excellent and good rate of hip joint function in HA group was significantly higher than that in IF group ( P value less than 0.05 ) . Conclusions Hemiarthroplasty with less postoperative complications , low reoperation rate and better function recovery in early stage provide a good choice for the treatment of super-aged patients with nondisplaced femoral neck fracture BACKGROUND Arthroplasty is now widely used to treat intra-capsular proximal femoral fractures ( PFFs ) in older patients , even when there is little or no displacement . However , whether arthroplasty is associated with lower mortality and complication rates in non-displaced or mildly displaced PFFs is unknown . The objectives of this prospect i ve study were : ( 1 ) to evaluate early mortality rates with the two treatment methods , ( 2 ) to identify risk factors for complications , ( 3 ) and to identify predictors of functional decline . HYPOTHESIS Arthroplasty and internal fixation produce similar outcomes in non-displaced fractures of patients older than 80 years with PFFs . MATERIAL AND METHODS This multicentre prospect i ve study included consecutive patients older than 80 years who were managed for intra-capsular PFFs at eight centres in 2014 .  Biometric data and geriatric assessment scores ( Parker Mobility Score , Katz Index of Independence , and Mini-Nutritional Assessment [ MNA ] score ) were collected before and 6 months after surgery . Independent risk factors were sought by multivariate analysis . We included 418 females and 124 males with a mean age of 87±4years . The distribution of Garden stages was stage I , n=56 ; stage II , n=33 ; stage III , n=130 ; and stage IV , n=323 . Arthroplasty was performed in 494 patients and internal fixation in 48 patients with non-displaced intra-capsular PFFs . RESULTS Mortality after 6 months was 16.4 % overall , with no significant difference between the two groups . By multivariate analysis , two factors were significantly associated with higher mortality , namely , male gender ( odds ratio [ OR ] , 3.24 ; 95 % confidence interval [ 95 % CI ] , 2.0 - 5.84 ; P<0.0001 ) and high ASA score ( OR , 1.56 ; 95 % CI , 1.07 - 2.26 ; P=0.019 ) . Two factors were independently associated with lower mortality , with 75 % predictive value , namely , high haematocrit ( OR , 0.8 ; 95 % CI , 0.7 - 0.9 ; P=0.001 ) and better Parker score ( OR , 0.5 ; 95 % CI , 0.3 - 0.8 ; P=0.01 ) . The cut-off values associated with a significant risk increase were 2 for the Parker score ( OR , 1.8 ; 95 % CI , 1.1 - 2.3 ; P=0.001 ) and 37 % for the haematocrit ( OR , 3.3 ; 95 % CI , 1.9 - 5.5 ; P=0.02 ) . Complications occurred in 5.5 % of patients . Surgical site infections were seen in 1.4 % of patients , all of whom had had arthroplasty . Blood loss was significantly greater with arthroplasty ( 311±197mL versus 201±165mL , P<0.0002 ) . Dependency worsened in 39 % of patients , and 31 % of patients lost self-sufficiency . A higher preoperative Parker score was associated with a lower risk of high postoperative dependency ( OR , 0.86 ; 95 % CI , 0.76 - 0.97 ; P=0.014 ) . DISCUSSION Neither treatment method was associated with decreased mortality or better function after intra-capsular PFFs in patients older than 80 years . Early mortality rates were consistent with previous reports . Among the risk factors identified in this study , age , preoperative self-sufficiency , and gender are not amenable to modification , in contrast to haematocrit and blood loss . CONCLUSION Internal fixation remains warranted in patients older than 80 years with non-displaced intra-capsular PFFs . LEVEL OF EVIDENCE III , prospect i ve case-control study Introduction : Although the preferred treatment for displaced femoral neck fractures in the elderly is hip arthroplasty , the treatment for impacted or undisplaced femoral neck fractures ( UFNF ) is still a subject of controversy . Our purpose was to systematic ally review studies of elderly patients with UFNF treated with internal fixation using screws :  ( i ) what is the reported mortality ; ( ii ) what is the reoperation rate ; ( iii ) what are the clinical and radiological outcomes ; and ( iv ) what is the method ological quality of the included studies ? Methods : This systematic review was performed through a search of PubMed and the Cochrane data base using a structured search algorithm including studies enrolling patients older than 60 years old , with UFNF treated with internal fixation using screws .  Our literature search returned 950 studies and 11 were selected for final abstract ion . Results : 6 studies reported mortality rate . At 1-year follow-up mortality was reported by 3 studies : 18.8 % ; 22 % , and 19 % . At 5 years , 1 study reported mortality rate of 42 % . Overall reoperation rate was reported by 9 studies and ranged from 8%-19 % , while conversion to hip arthroplasty was performed in the range between 8 % and 16 % according to 6 studies . Conclusions : Internal fixation with cannulated screws for UFNF in the elderly is a valuable option , although it has substantial reoperation and mortality rates . Further prospect i ve high- quality , r and omised controlled trials are required to establish the optimal approach for the treatment of UFNF INTRODUCTION The objective of this study was to identify indications and predictors for subsequent surgeries in the same hip and to evaluate life expectancy following screw fixation of undisplaced femoral neck fractures ( FNF ) . The study further aim ed to determine the necessary follow-up time for future studies aim ing to evaluate the treatment of such fractures . MATERIAL S AND METHODS This is a single-center retrospective cohort study with prospect ively collected data including skeletally mature patients with undisplaced FNFs operated between 2005 and 2013 . Gender , age at fracture , American Society of Anesthesiologists score , smoking status and excess use of alcohol were retrieved from electronical medical records . Further , complications leading to all consecutive reoperations were registered along with time from primary operation to all reoperations , type of procedure during subsequent surgeries and time of death . RESULTS 383 patients with a median ( range ) follow-up of 77 ( 23 - 125 ) months were identified . Within 1 , 2 and 5 years from primary surgery , 8 % , 17 % and 21 % respectively , had at least one subsequent surgery in the same hip . 10 % of the patients underwent salvage arthroplasty  , however , in long time survivors ; conversion to arthroplasty was estimated in one out of four . Posterior tilt of the femoral head was a predictor for new surgeries due to instability of the bone-implant construct , but not for later avascular necrosis . For patients 70 years or older , the one-year mortality in men was 32 % with an expected survival of approx . 2.5 years , compared to 17 % and 5.5 years in women . CONCLUSIONS Screw fixation of undisplaced femoral neck fractures appears to be a safe procedure in particular in the absence of a posterior tilt of the femoral head . Conversion to arthroplasty was estimated to occur in one out of four of long time survivors . Men have a particularly poor medical prognosis and should receive careful medical attention . In order to capture 80 % of reoperations , clinical studies and register studies must have a follow-up time of at least two years Background Reported revision of internal fixation for undisplaced intracapsular hip fractures is between 12 and 17 % at 1 year . This risk is greater for elderly patients , for whom mortality after such a fracture is also higher . Our purpose was to identify predictors of fixation failure and mortality for elderly patients sustaining undisplaced intracapsular hip fractures , and to assess whether their socioeconomic status affected their outcome . Methods During a 3-year period we prospect ively compiled a consecutive series of 162 elderly ( ≥65 years old ) patients who underwent internal fixation for an undisplaced ( Garden stage I or II ) intracapsular hip fracture . Patient demographics , American Society of Anesthesiologists ( ASA ) grade , and posterior tilt ( measured on the lateral radiograph ) were recorded pre-operatively . All patients were followed up for a minimum of 1 year . Each patient ’s socioeconomic status was assigned by use of the Scottish Index of Multiple Deprivation . Patient mortality was established by use of the General Register Office for Scotl and . Results There were 28 failures of fixation during the study period . In Cox regression analysis , ASA grade and the presence of posterior tilt ( p < 0.0001 ) were significant independent predictors of fixation failure . Overall unadjusted mortality at 1 year was 19 % ( n = 30/162 ) . Cox regression analysis also affirmed ASA grade to be the only significant independent predictor of 1-year mortality ( p = 0.003 ) . The st and ardised mortality rate for the cohort was 2.3 ( p < 0.001 ) , and was significantly greater for patients less than 80 years of age ( p = 0.004 ) . Socioeconomic status did not affect outcome , but the most deprived patients sustain their fracture at a significantly younger age ( p = 0.001 ) . Conclusion We have demonstrated that ASA grade and posterior tilt of the femoral neck are independent predictors of fixation failure of undisplaced intracapsular hip fractures in elderly patients , and ASA grade was also an independent predictor of mortality Abstract Hemiarthroplasty is the most commonly used treatment for displaced femoral neck fractures in the elderly . There is limited evidence in the literature of improved functional outcome with cemented implants , although serious cement-related complications have been reported . We performed a r and omized , controlled trial in patients 70 years and older comparing a cemented implant ( 112 hips )  with an uncemented , hydroxyapatite-coated implant ( 108 hips ) , both with a bipolar head . The mean Harris hip score showed equivalence between the groups , with 70.9 in the cemented group and 72.1 in the uncemented group after 3 months ( mean difference , 1.2 ) and 78.9 and 79.8 after 12 months ( mean difference , 0.9 ) . In the uncemented group , the mean duration of surgery was 12.4 minutes shorter and the mean intraoperative blood loss was 89 mL less . The Barthel Index and EQ-5D scores did not show any differences between the groups . The rates of complications and mortality were similar between groups . Both arthroplasties may be used with good results after displaced femoral neck fractures . Level of Evidence : Level I , therapeutic study . See the Guidelines for Authors for a complete description of levels of evidence & NA ;  Pain intensity is frequently measured on an 11‐point pain intensity numerical rating scale ( PI‐NRS ) , where 0=no pain and 10=worst possible pain . However , it is difficult to interpret the clinical importance of changes from baseline on this scale ( such as a 1‐ or 2‐point change ) . To date , there are no data driven estimates for clinical ly important differences in pain intensity scales used for chronic pain studies . We have estimated a clinical ly important difference on this scale by relating it to global assessment s of change in multiple studies of chronic pain . Data on 2724 subjects from 1 
    Output:
    
Conclusions Compared with the internal fixation group , patients that underwent hemiarthroplasty had a lower reoperation rate and an equivalent overall mortality rate .
Our meta- analysis suggests that hemiarthroplasty might be a better treatment choice than internal fixation in treating elderly patients with an undisplaced femoral neck fracture