Fixation of femoral neck fracture. Prospective comparison of von Bahr screws, Gouffon screws, and Hessel pins

Surgical interventions for treating intracapsular hip fractures in older adults: a network meta-analysis

BACKGROUND

Hip fractures are a major healthcare problem, presenting a considerable challenge and burden to individuals and healthcare systems. The number of hip fractures globally is rising rapidly. The majority of intracapsular hip fractures are treated surgically.

OBJECTIVES

To assess the relative effects (benefits and harms) of all surgical treatments used in the management of intracapsular hip fractures in older adults, using a network meta-analysis of randomised trials, and to generate a hierarchy of interventions according to their outcomes.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, Web of Science, and five other databases in July 2020. We also searched clinical trials databases, conference proceedings, reference lists of retrieved articles and conducted backward-citation searches.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and quasi-RCTs comparing different treatments for fragility intracapsular hip fractures in older adults. We included total hip arthroplasties (THAs), hemiarthroplasties (HAs), internal fixation, and non-operative treatments. We excluded studies of people with hip fracture with specific pathologies other than osteoporosis or resulting from high-energy trauma.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies for inclusion. One review author completed data extraction which was checked by a second review author. We collected data for three outcomes at different time points: mortality and health-related quality of life (HRQoL) - both reported within 4 months, at 12 months, and after 24 months of surgery, and unplanned return to theatre (at end of study follow-up). We performed a network meta-analysis (NMA) with Stata software, using frequentist methods, and calculated the differences between treatments using risk ratios (RRs) and standardised mean differences (SMDs) and their corresponding 95% confidence intervals (CIs). We also performed direct comparisons using the same codes.

MAIN RESULTS

We included 119 studies (102 RCTS, 17 quasi-RCTs) with 17,653 participants with 17,669 intracapsular fractures in the review; 83% of fractures were displaced. The mean participant age ranged from 60 to 87 years and 73% were women.  After discussion with clinical experts, we selected 12 nodes that represented the best balance between clinical plausibility and efficiency of the networks: cemented modern unipolar HA, dynamic fixed angle plate, uncemented first-generation bipolar HA, uncemented modern bipolar HA, cemented modern bipolar HA, uncemented first-generation unipolar HA, uncemented modern unipolar HA, THA with single articulation, dual-mobility THA, pins, screws, and non-operative treatment. Seventy-five studies (with 11,855 participants) with data for at least two of these treatments contributed to the NMA. We selected cemented modern unipolar HA as a reference treatment against which other treatments were compared. This was a common treatment in the networks, providing a clinically appropriate comparison. In order to provide a concise summary of the results, we report only network estimates when there was evidence of difference between treatments. We downgraded the certainty of the evidence for serious and very serious risks of bias and when estimates included possible transitivity, particularly for internal fixation which included more undisplaced fractures. We also downgraded for incoherence, or inconsistency in indirect estimates, although this affected few estimates. Most estimates included the possibility of benefits and harms, and we downgraded the evidence for these treatments for imprecision.  We found that cemented modern unipolar HA, dynamic fixed angle plate and pins seemed to have the greatest likelihood of reducing mortality at 12 months. Overall, 23.5% of participants who received the reference treatment died within 12 months of surgery. Uncemented modern bipolar HA had higher mortality than the reference treatment (RR 1.37, 95% CI 1.02 to 1.85; derived only from indirect evidence; low-certainty evidence), and THA with single articulation also had higher mortality (network estimate RR 1.62, 95% CI 1.13 to 2.32; derived from direct evidence from 2 studies with 225 participants, and indirect evidence; very low-certainty evidence). In the remaining treatments, the certainty of the evidence ranged from low to very low, and we noted no evidence of any differences in mortality at 12 months.  We found that THA (single articulation), cemented modern bipolar HA and uncemented modern bipolar HA seemed to have the greatest likelihood of improving HRQoL at 12 months. This network was comparatively sparse compared to other outcomes and the certainty of the evidence of differences between treatments was very low. We noted no evidence of any differences in HRQoL at 12 months, although estimates were imprecise. We found that arthroplasty treatments seemed to have a greater likelihood of reducing unplanned return to theatre than internal fixation and non-operative treatment. We estimated that 4.3% of participants who received the reference treatment returned to theatre during the study follow-up. Compared to this treatment, we found low-certainty evidence that more participants returned to theatre if they were treated with a dynamic fixed angle plate (network estimate RR 4.63, 95% CI 2.94 to 7.30; from direct evidence from 1 study with 190 participants, and indirect evidence). We found very low-certainty evidence that more participants returned to theatre when treated with pins (RR 4.16, 95% CI 2.53 to 6.84; only from indirect evidence), screws (network estimate RR 5.04, 95% CI 3.25 to 7.82; from direct evidence from 2 studies with 278 participants, and indirect evidence), and non-operative treatment (RR 5.41, 95% CI 1.80 to 16.26; only from indirect evidence). There was very low-certainty evidence of a tendency for an increased risk of unplanned return to theatre for all of the arthroplasty treatments, and in particular for THA, compared with cemented modern unipolar HA, with little evidence to suggest the size of this difference varied strongly between the arthroplasty treatments.

AUTHORS' CONCLUSIONS

There was considerable variability in the ranking of each treatment such that there was no one outstanding, or subset of outstanding, superior treatments. However, cemented modern arthroplasties tended to more often yield better outcomes than alternative treatments and may be a more successful approach than internal fixation. There is no evidence of a difference between THA (single articulation) and cemented modern unipolar HA in the outcomes measured in this review. THA may be an appropriate treatment for a subset of people with intracapsular fracture but we have not explored this further.

Internal fixation implants for intracapsular hip fractures in older adults

BACKGROUND

Hip fractures are a major healthcare problem, presenting a huge challenge and burden to patients, healthcare systems and society. The increased proportion of older adults in the world population means that the absolute number of hip fractures is rising rapidly across the globe. The majority of hip fractures are treated surgically. This review evaluates evidence for types of internal fixation implants used in joint-preserving surgery for intracapsular hip fractures.

OBJECTIVES

To determine the relative effects (benefits and harms) of different implants for the internal fixation of intracapsular hip fractures in older adults.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, Web of Science, Cochrane Database of Systematic Reviews, Epistemonikos, Proquest Dissertations and Theses, and National Technical Information Service in July 2020. We also searched clinical trials databases, conference proceedings, reference lists of retrieved articles and conducted backward-citation searches.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and quasi-RCTs comparing implants used for internal fixation of fragility intracapsular proximal femoral fractures in older adults. Types of implants were smooth pins (these include pins with fold-out hooks), screws, or fixed angle plates. We excluded studies in which all or most fractures were caused by specific pathologies other than osteoporosis or were the result of a high energy trauma.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies for inclusion. One review author extracted data and assessed risk of bias which was checked by a second review author. We collected data for seven outcomes: activities of daily living (ADL), delirium, functional status, health-related quality of life (HRQoL), mobility, mortality (reported within four months of surgery as early mortality, and at 12 months since surgery), and unplanned return to theatre for treating a complication resulting directly or indirectly from the primary procedure (such as deep infection or non-union). We assessed the certainty of the evidence for these outcomes using GRADE.

MAIN RESULTS

We included 38 studies (32 RCTs, six quasi-RCTs) with 8585 participants with 8590 intracapsular fractures. The mean ages of participants in the studies ranged from 60 to 84 years; 73% were women, and 38% of fractures were undisplaced. We report here the findings of the four main comparisons, which were between different categories of implants. We downgraded the certainty of the outcomes for imprecision (when data were available from insufficient numbers of participants or the confidence interval (CI) was wide), study limitations (e.g. high or unclear risks of bias), and inconsistency (when we noted substantial levels of statistical heterogeneity). Smooth pins versus fixed angle plate (four studies, 1313 participants) We found very low-certainty evidence of little or no difference between the two implant types in independent mobility with no more than one walking stick (1 study, 112 participants), early mortality (1 study, 383 participants), mortality at 12 months (2 studies, 661 participants), and unplanned return to theatre (3 studies, 736 participants). No studies reported on ADL, delirium, functional status, or HRQoL. Screws versus fixed angle plates (11 studies, 2471 participants) We found low-certainty evidence of no clinically important differences between the two implant types in functional status using WOMAC (MD -3.18, 95% CI -6.35 to -0.01; 2 studies, 498 participants; range of scores from 0 to 96, lower values indicate better function), and HRQoL using EQ-5D (MD 0.03, 95% CI 0.00 to 0.06; 2 studies, 521 participants; range -0.654 (worst), 0 (dead), 1 (best)). We also found low-certainty evidence showing little or no difference between the two implant types in mortality at 12 months (RR 1.04, 95% CI 0.83 to 1.31; 7 studies, 1690 participants), and unplanned return to theatre (RR 1.10, 95% CI 0.95 to 1.26; 11 studies, 2321 participants). We found very low-certainty evidence of little or no difference between the two implant types in independent mobility (1 study, 70 participants), and early mortality (3 studies, 467 participants). No studies reported on ADL or delirium. Screws versus smooth pins (seven studies, 1119 participants) We found low-certainty evidence of no or little difference between the two implant types in mortality at 12 months (RR 1.07, 95% CI 0.85 to 1.35; 6 studies, 1005 participants; low-certainty evidence). We found very low-certainty evidence of little or no difference between the two implant types in early mortality (3 studies, 584 participants) and unplanned return to theatre (5 studies, 862 participants). No studies reported on ADL, delirium, functional status, HRQoL, or mobility. Screws or smooth pins versus fixed angle plates (15 studies, 3784 participants) In this comparison, we combined data from the first two comparison groups. We found low-certainty evidence of no or little difference between the two groups of implants in mortality at 12 months (RR 1.04, 95% CI.083 to 1.31; 7 studies, 1690 participants) and unplanned return to theatre (RR 1.02, 95% CI 0.88 to 1.18; 14 studies, 3057 participants). We found very low-certainty evidence of little or no difference between the two groups of implants in independent mobility (2 studies, 182 participants), and early mortality (4 studies, 850 participants). We found no additional evidence to support the findings for functional status or HRQoL as reported in 'Screws versus fixed angle plates'. No studies reported ADL or delirium.

AUTHORS' CONCLUSIONS

There is low-certainty evidence that there may be little or no difference between screws and fixed angle plates in functional status, HRQoL, mortality at 12 months, or unplanned return to theatre; and between screws and pins in mortality at 12 months. The limited and very low-certainty evidence for the outcomes for which data were available for the smooth pins versus fixed angle plates comparison, as well as the other outcomes for which data were available for the screws and fixed angle plates, and screws and pins comparisons means we have very little confidence in the estimates of effect for these outcomes. Additional RCTs would increase the certainty of the evidence. We encourage such studies to report outcomes consistent with the core outcome set for hip fracture, including long-term quality of life indicators such as ADL and mobility.

Finite element analysis of the effect of cannulated screw placement and drilling frequency on femoral neck fracture fixation

BACKGROUND

Positioning of the implanted cannulated screw is paramount for stable femoral neck fracture fixation. To avoid overdrilling, the aim of this study is to determine the optimum configuration of three cannulated screws employed in femoral neck fracture fixation.

METHODS

Using a CT scan from a 28 year old healthy male, several models of femoral neck fracture fixation were developed using finite element analysis. After drilling small holes (in either fixed or random patterns) for screw insertion, the mechanical stresses on the screws were compared for three fracture types.

RESULTS

The inverted isosceles triangle was found to be the best screw configuration. Using finite element analysis, the upper limit of drilling frequency and the maximum stress on the screws for 30°, 50°, and 70° drilling were 14, 16, and 19 times and 46.1MPa, 61.9MPa, and 51.0MPa, respectively. The upper limit of drilling frequency and the maximum stress on the screws for subcapital type, transcervical type, and basicervical type were 14, 16, and 40 times and 24.7MPa, 61.9MPa, and 113.5MPa, respectively.

CONCLUSIONS

Results of this study had supported the use of the inverted isosceles triangle as the best screw configuration for femoral neck fracture fixation. Screw position, Pauwels angle, and drilling frequency can all affect the mechanical strength of femoral neck fracture fixation.

Two cannulated hip screws for femoral neck fractures: treatment of choice or asking for trouble?

INTRODUCTION

Undisplaced intracapsular fractures are predominantly treated with a minimally invasive fixation technique, whereas the standard treatment for displaced intracapsular fractures is still a subject of discussion. The purpose of this study was to identify the determinants influencing the outcome of intracapsular femoral neck fractures, treated with two cannulated hip screws.

PATIENTS AND METHODS

From January 1998 through December 2002 data of all consecutive patients with an intracapsular femoral fracture, treated with two cannulated screws, were documented. Consolidation was chosen as the primary endpoint, mortality and a reoperation for replacement of osteosynthesis were defined secondary endpoints.

RESULTS

One hundred and twelve patients were included in the study. Fifty six percent of the intracapsular fractures healed within 1 year. Consolidation was accomplished in 95% of the stable fractures. Consolidation rates were negatively influenced by unstable fractures and inadequate anatomical reduction. The position of the screws did not influence consolidation rates. Reintervention rates were related to the number of local complications and the fracture type.

CONCLUSION

In conclusion, the results of this study show that in case of operative treatment, undisplaced femoral neck fractures can be adequately fixated by two cannulated hip screws. Unstable, anatomically reduced femoral neck fracture (Garden III/IV) may be treated with a more stable implant (e.g. DHS) to avoid redisplacement. If adequate reduction cannot be achieved, endoprosthetic replacement is recommended.

The Value of Washers in Cannulated Screw Fixation of Femoral Neck Fractures

BACKGROUND

Given the limited evidence to support the technical aspects of screw placement for treatment of femoral neck fractures, we conducted an observational study to evaluate demographic and radiographic variables associated with fixation failure.

METHODS

Eligible patients with femoral neck fractures were treated with multiple cannulated screws across three academic centers during a 6-year period. The following variables were evaluated for their predictive value for fixation failure: age, gender, fracture type, presence of comminution, total number of screws, the absence of a washer, the screw configuration, reduction quality, the distance of the most inferior screw to the inferior neck, and screw alignment. Variables were evaluated separately and in a multivariable regression model.

RESULTS

Eighty patients were included in the study. The overall failure rate was 30%. We identified four variables associated with fixation failure. These included the lack of washers (odds ratio [OR], 11.2; p = 0.03), imperfect quality of reduction (OR, 9.7; p < 0.01), age greater than 75 years (OR, 5.1; p = 0.04), and displaced versus undisplaced fracture type (OR, 3.8; p < 0.01). These four variables accounted for 43% of the variability in fixation failure (R(2) = 0.43). All other variables including the distance of the most inferior screw to the inferior/medial neck were found to be not significant.

CONCLUSION

This study confirms previous findings in the literature that increased age, a displaced fracture type, and poor reduction increase the risk of fixation failure. Contradictory to current belief, there was no significant association between the distance of the inferior screw to the inferior/medial femoral neck cortex and fixation failure. A novel finding of the present study is that the use of washers significantly decreases the risk of fixation failure.

Optimum configuration of cannulated hip screws for the fixation of intracapsular hip fractures: a biomechanical study

The radiographs of a sample of patients who had canulated hip screw fixation for intracapsular femoral neck fractures were reviewed in our region. There were six different types of configurations used in these fixations which are divided into two groups: (I) triangular configurations, consisting of two parallel screws with a third screw placed either superiorly, inferiorly, anteriorly or posteriorly; and (II) linear configurations with two or three screws in a vertical line. In our study, we tested the relative strength of each configuration in a laboratory setting using synthetic bone models. Statistical analysis, at 5% significance level, using two-way ANOVA and post-hoc test was carried out to test the differences of the results between the configurations.Our results clearly show that the triangular configurations had a higher peak load, higher ultimate load, less displacement and more energy absorption before failure than other configurations.

Internal fixation implants for intracapsular proximal femoral fractures in adults

BACKGROUND

Numerous different implants with screws, pins and side plates have been used for the internal fixation of intracapsular hip fractures.

OBJECTIVES

To determine from randomised trials which implant is superior for the internal fixation of intracapsular proximal femoral fractures.

SEARCH STRATEGY

We searched the Cochrane Musculoskeletal Injuries Group specialised register. The date of the most recent search was December 2000.

SELECTION CRITERIA

Randomised and quasi-randomised trials comparing different implants for the internal fixation of intracapsular hip fractures in adults.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed trial quality, by use of a ten item scale, and extracted data. Additional information was sought from trialists. After grouping by implant type, comparable groups of trials were subgrouped and where appropriate, data were pooled using the fixed effects model.

MAIN RESULTS

Twenty-seven studies involving 5269 participants (5274 fractures) were included in the study. Considerable variation in the quality of methodology between studies was found and biases due to familiarity with some of the implants were noted. None of the implants tested were found to be significantly superior for any of the outcome measures related to fracture healing complications or mortality. The sliding hip screw was found to take longer to insert and to have an increased operative blood loss compared with multiple screws or pins.

REVIEWER'S CONCLUSIONS

No clear conclusions can be made on the choice of implant for internal fixation of intracapsular fractures from the available evidence within randomised trials.

An algorithm for preoperative prediction of reoperation risk after internal fixation of femoral neck fractures

An algorithm was designed for preoperative prediction of the risk for reoperation, and the mortality risk, after internal fixation of femoral neck fractures. Out of 51 reviewed studies of femoral neck fractures, eight met specified inclusion criteria such as low dropout rates, a minimum of ten surgeons performing the surgery, a minimum of 2 years follow-up, and a standard age, sex, and Garden class distribution. Five of these studies were used for the construction of the algorithm, and the remaining three for testing the specificity and sensitivity of the algorithm. A separate analysis of the influence of age on the reoperation rate was also performed. In the analysis of 399 reviewed cases of femoral neck fractures, the specificity for the algorithm in predicting the risk for reoperation was 96%, and the sensitivity was 51%. The positive predictive value for the algorithm in predicting the risk for reoperation was 77%, which was three times higher compared to the commonly used predictors age and Garden class (positive predictive value 25%). For prediction of the mortality risk the positive predictive value for-the algorithm was 57%.

Cannulated screws for fixation of femoral neck fractures. No difference between Uppsala screws and Richards screws in a randomized prospective study of 268 cases

We compared 2 types of cannulated hip screws in a randomized prospective study of 268 femoral neck fractures. Complications were defined as penetration of the screw into the joint, early redisplacement, nonunion or segmental collapse. During the first year, complications were noted in 31 of 130 patients treated with 3 Richards screws and in 34 of 138 patients treated with 2 Uppsala screws. Secondary arthroplasty was performed in 17 cases in the Richards group and in 16 cases in the Uppsala group. Clinical outcome did not differ between the groups.

Choice of implant for internal fixation of femoral neck fractures. Meta-analysis of 25 randomised trials including 4,925 patients

We reviewed all randomised trials comparing different implants for treating intracapsular fractures of the hip and, where possible, the data were combined. 25 randomised trials were identified involving 4,925 patients. Screws appeared to be superior to pins. It was not possible to determine the optimum number or type of screws. No advantage was shown for an implant with a side-plate.

Are hard-copy prints from peroperative fluoroscopy images useful as documentation?

We have examined the applicability of peroperative image documentation, in promoting early mobilization after osteosynthesis and saving the standard X-ray examination. One hundred and twenty-three patients with proximal femoral fractures were included in the investigation. Hard-copy reprints were recorded from peroperative fluoroscopy images by Fuji Film Thermal Imaging System FTI 200. These reprints were compared with the standard X-rays to assess the quality of the osteosynthesis and possible restriction in mobilization. The specificity of finding an unstable osteosynthesis was 0.40, whereas the sensitivity of finding a stable osteosynthesis was 0.96. In all, four unstable osteosyntheses were overlooked on the hard copy reprints. The specificity of finding patients in need of restricted mobilization was 0.44 and the sensitivity of finding patients allowed free mobilization was 0.93. Eight patients needing restricted mobilization were overlooked on the reprints. Hard-copy images do not safely reveal unstable osteosynthesis and cannot replace the standard X-rays taken postoperatively.

Outcomes after displaced fractures of the femoral neck. A meta-analysis of one hundred and six published reports

Methods of meta-analysis, a technique for the combination of data from multiple sources, were applied to analyze 106 reports of the treatment of displaced fractures of the femoral neck. Two years or less after primary internal fixation of a displaced fracture of the femoral neck, a non-union had developed in 33 per cent of the patients and avascular necrosis, in 16 per cent. The rate of performance of a second operation within two years ranged from 20 to 36 per cent after internal fixation and from 6 to 18 per cent after hemiarthroplasty (relative risk, 2.6; 95 per cent confidence interval, 1.4 to 4.6). Conversion to an arthroplasty was the most common reoperation after internal fixation and accounted for about two-thirds of these procedures. The remaining one-third of the reoperations were for removal of the implant or revision of the internal fixation. For the patients who had had a hemiarthroplasty, the most common reoperations were conversion to a total hip replacement, removal or revision of the prosthesis, and débridement of the wound. Although we observed an increase in the rate of mortality at thirty days after primary hemiarthroplasty compared with that after primary internal fixation, the difference was not significant (p = 0.22) and did not persist beyond three months. The absolute difference in perioperative mortality between the two groups was small. An anterior operative approach for arthroplasty consistently was associated with a lower rate of mortality at two months than was a posterior approach. Some reports showed promising results after total hip replacement for displaced fractures of the femoral neck; however, randomized clinical trials are still needed to establish the value of this treatment.

Internal fixation of femoral neck fractures. Dynamic Hip and Gouffon screws compared in 73 patients

A prospective, randomized study comparing the Dynamic Hip screws and the Gouffon screws in the treatment of femoral neck fractures was terminated before the planned number of patients had been admitted, owing to a preponderance of early failure of the Gouffon screws (P 0.014); thus only 73 patients entered the study. After three years' follow-up, 25/38 Gouffon screws and 12/35 Dynamic Hip screws had failed. Six patients treated with Gouffon screws and 14 treated with Dynamic Hip screws had died. The outcome still favoured the use of Dynamic Hip screws (P 0.02).

Uppsala screws or Hansson pins for internal fixation of femoral neck fractures? A prospective study of 180 cases

In a prospective randomized trial, two methods of internal fixation of femoral neck fractures were compared. Totally, 179 patients with 180 fractures were treated with either two Uppsala screws (n 96) or two Hansson pins (n 84). In all, 130 fractures were primarily displaced (Garden stages III and IV), whereas 88 percent of the fractures in both groups were well reduced. The patients were followed clinically and radiographically for 1 year. Thirty-six patients died within 12 months after the operation. The functional results and the incidence of segmental collapse and nonunion did not differ between the groups. However, at the 4-month follow-up, 2 of 59 of the Garden's stages III and IV in the Uppsala-screw group were found displaced, whereas the corresponding result in the Hansson-pin group was 9 of 52 (P = 0.03).

Fixation of femoral neck fractures. A four-flanged nail versus threaded pins in 200 cases

Two methods of internal fixation for cervical hip fractures were compared in a "randomized to surgeons" type of study. One hundred patients were treated with the Rydell four-flanged nail and 100 with the Gouffon pins. Redisplacement, nonunion, or segmental collapse occurred in 27 patients operated on with the Rydell nail and in 29 patients operated on with the Gouffon pins. According to the actuarial method of follow-up, the failure rates after 2 years were 31 and 33 percent in the two groups.