Improved operations for femoral neck fracture. A radiographic evaluation

Reduction Techniques for Young Femoral Neck Fractures

Young femoral neck fractures remain challenging fractures to treat. Reduction has repeatedly been shown to be the single most important determinant of patient outcome, and treating surgeons should do all they can to achieve anatomic reduction because this is an outcome variable within the surgeon's control. Whether an open or closed reduction is performed, we hope to provide the reader with reduction strategies when faced with this difficult fracture pattern. In addition, we hope to review indications and techniques for using the various treatment implants/modalities that are currently available as they pertain to reduction and fixation.

Incidence, Magnitude, and Predictors of Shortening in Young Femoral Neck Fractures

OBJECTIVES

To describe the incidence and magnitude of femoral neck fracture shortening in patients age younger than 60 years. Secondarily, to examine predictors of fracture shortening.

DESIGN

Retrospective chart review.

SETTING

Level I trauma centre.

PATIENTS/PARTICIPANTS

Sixty-five patients with a median age of 51 years (interquartile range: 42-56 years) were included. Seventy-one percent were male, 75% were displaced fractures, and 78% were treated with cancellous screws.

INTERVENTION

Internal fixation with multiple cancellous screws or sliding hip screw (SHS) + derotation screw.

MAIN OUTCOME MEASUREMENTS

Radiographic femoral neck shortening at a minimum of 6 weeks after fixation.

RESULTS

Fifty-four percent of patients had ≥5 mm of femoral neck shortening (22% had between ≥5 and <10 mm and 32% ≥10 mm). Initially, displaced fractures shortened more than undisplaced fractures (mean: 8.1 vs. 2.2 mm, P < 0.001), and fractures treated with SHS + derotation screw shortened more than fractures with cancellous screws alone (10.7 vs. 5.5 mm, P = 0.03). Even when adjusting for initial fracture displacement, fractures treated with SHS + derotation screw shortened an average of 2.2 mm more than fractures treated with screws alone (P = 0.03).

CONCLUSIONS

The incidence of clinically significant shortening in our young femoral neck fracture population was higher than anticipated, and 32% of patients experienced severe shortening of >1 cm. Our findings highlight the need for further research to determine the impact of severe shortening on functional outcome and to determine if implant selection affects fracture shortening.

LEVEL OF EVIDENCE

Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Fixation using alternative implants for the treatment of hip fractures (FAITH): design and rationale for a multi-centre randomized trial comparing sliding hip screws and cancellous screws on revision surgery rates and quality of life in the treatment of femoral neck fractures

BACKGROUND

Hip fractures are a common type of fragility fracture that afflict 293,000 Americans (over 5,000 per week) and 35,000 Canadians (over 670 per week) annually. Despite the large population impact the optimal fixation technique for low energy femoral neck fractures remains controversial. The primary objective of the FAITH study is to assess the impact of cancellous screw fixation versus sliding hip screws on rates of revision surgery at 24 months in individuals with femoral neck fractures. The secondary objective is to determine the impact on health-related quality of life, functional outcomes, health state utilities, fracture healing, mortality and fracture-related adverse events.

METHODS/DESIGN

FAITH is a multi-centre, multi-national randomized controlled trial utilizing minimization to determine patient allocation. Surgeons in North America, Europe, Australia, and Asia will recruit a total of at least 1,000 patients with low-energy femoral neck fractures. Using central randomization, patients will be allocated to receive surgical treatment with cancellous screws or a sliding hip screw. Patient outcomes will be assessed at one week (baseline), 10 weeks, 6, 12, 18, and 24 months post initial fixation. We will independently adjudicate revision surgery and complications within 24 months of the initial fixation. Outcome analysis will be performed using a Cox proportional hazards model and likelihood ratio test.

DISCUSSION

This study represents major international efforts to definitively resolve the treatment of low-energy femoral neck fractures. This trial will not only change current Orthopaedic practice, but will also set a benchmark for the conduct of future Orthopaedic trials.

TRIAL REGISTRATION

The FAITH trial is registered at ClinicalTrials.gov (Identifier NCT00761813).

Proximal femoral fractures: Principles of management and review of literature

The purpose of this study was to review the principles involved in the management of proximal femoral fractures as reported in the literature.

METHODS

A medical literature search in the MEDLINE (PubMed) and Cochrane database was undertaken to review strategies and principles in proximal femoral fracture treatment. Randomized control trials and meta analysis were given preference while case reports/small series were rejected.

RESULTS AND CONCLUSIONS

Early anatomical reduction and surgical fixation remains the best option to reduce the risk of complications like non-union and avascular necrosis in treating fracture neck femurs. Cancellous screws continue to be the preferred treatment for fixation of neck femur fractures in younger population until the benefit of using sliding hip screws is validated by large multicentric studies. In the geriatric age group, early prosthetic replacement brings down the mortality and morbidity associated with neck femur fractures. Sliding hip screw (DHS) is the best available option for stable inter trochanteric fractures. The use of intramedullary nails e.g. PFN is beneficial in treating inter trochanteric fractures with comminution and loss of lateral buttress. Intramedullary implants have been proven to have increased success rates in subtrochanteric fractures and should be preferred over extramedullary plate fixation systems.

Optimal internal fixation for femoral neck fractures: multiple screws or sliding hip screws?

INTRODUCTION

The number of hip fractures is likely to exceed 500,000 in the United States and 88,000 in Canada annually over the next 40 years. Hip fractures are associated with a 30% mortality rate at 1 year and profound temporary, and sometimes permanent, impairment of independence and quality of life.

OBJECTIVES

Although much focus has centered around the comparison of arthroplasty versus internal fixation devices in the treatment of femoral neck fractures, the optimal approach for internal fixation has been largely ignored. Identifying the optimal technique for internal fixation could reduce the historically high rates of revision surgery that have fueled arguments against fixing patients with displaced femoral neck fractures.

RESULTS

Both indirect and direct comparisons suggest a possible benefit for a sliding hip screw over multiple cancellous screws in reducing the need for revision surgery. The indirect nature of the comparison from the meta-analysis of arthroplasty versus internal fixation, and the small sample sizes, methodological limitations, and nonsignificant pooled estimate from the direct comparisons, leaves the issue very much in doubt.

CONCLUSIONS

Although the rationale for arthroplasty continues to gain popularity, previous studies suggest that we have yet to identify the best approach for internal fixation. Previous trials suggest that the issue is largely unresolved and solutions will likely come from larger randomized trials comparing alternative devices for fixing the hip.

In vitro femoral stiffness after femoral neck osteotomy and osteosynthesis with defined surgical errors

In our search for an osteosynthesis device that would tolerate the surgical errors of the inexperienced surgeon, we tested in vitro femoral stiffness in 75 human osteoporotic femora after internal fixation of a cervical neck osteotomy using three commonly used devices: two von Bahr screws (A. Ericsson AB, Sweden), two cannulated screws (Uppsala type, Olmed AB, Sweden), and two hookpins (LiH, PSAB, Sweden). The first device has its main grip in the cancellous bone by threads; the second has grip in cancellous and subchondral bone by threads; and the third, which has no threads, has its grip in cancellous bone by a hook pin. The intact specimen was in all instances stiffer (22-63%) than the osteosynthesized specimen (p < 0.001). An osteosynthesized femur with perfectly reduced bone ends was 14-23% stiffer than when reduction of the bone ends was insufficient, irrespective of device malposition (p < 0.001). Insufficient reduction of the osteotomy leaving a 20 degrees dorsal angulation of the femoral head combined with too far ventrally placed screws resulted in the lowest femoral stiffness. If reduction of osteotomy was sufficient, screws placed too far ventrally or converging screws did not result in decreased stiffness compared with optimal screw placement. Irrespective of the quality of reduction, osteosynthesis with the Uppsala screw resulted in all instances in a higher stiffness than using the other devices (p < 0.01). With the Uppsala screw design, femoral stiffness after optimal osteosynthesis was reduced by 22% compared with the intact femur, and in the most unfavorable position with combined malreduction and malpositioning it was reduced by 42%. Corresponding values for the von Bahr screws were 29% and 46%, respectively, and for the LiH screws 47% and 63%, respectively. Use of a device with threads and grip in the subchondral bone is recommended for fixation of femoral neck fractures in osteoporotic bone. Furthermore, the importance of anatomical reduction for fracture fixation is emphasized.

An algorithm for assessment of fracture displacement and pin positions in femoral neck fractures

A method for determination of both the displacement of the femoral head and the position of the fixation device in fixed femoral neck fractures is described. In routine AP and lateral radiographs of the hip, measurements are made of femoral neck-shaft angle, the diameter of the femoral head and neck, the distances from the center of the femoral head to the femoral neck axis and the distances from the femoral neck axis to the fixating screws. From these values the position of the femoral head and the fixating screws are determined by geometric calculations. A computer program in Q-BASIC was devised to perform the calculations and to produce graphic displays of cross-sections of the femoral head and neck, with the displacement of the head and the screw positions indicated. The accuracy of the method was evaluated by a new method using axial radiographs of hip specimens, which were compared with the computer-plotted graphs of the femoral head and neck. The mean error of the method was found to be +/- 5% of the femoral head diameter, approximately 2.5 mm.

Cortical screw support in femoral neck fractures. A radiographic analysis of 87 fractures with a new mensuration technique

In 87 femoral neck fractures, operated on with 2 von Bahr screws and followed for up to 2 years, the positions of the fixating screws were determined with a new mensuration technique which compensates for the variations in hip rotation in routine radiographs. The union rate of the fractures was related to the position of the screws. A posterior placement of the proximal screw and an inferior placement of the distal screw in both the femoral head and neck improved the outcome substantially.

Femoral neck fracture fixation with hook-pins. 2-year results and learning curve in 626 prospective cases

We performed a prospective 2-year follow-up study of 626 consecutive femoral neck fractures treated with closed reduction and hook-pin fixation in all cases. The woman:man ratio was 2.9:1, the displaced:undisplaced fracture ratio 2.6:1. Mean patient age was 78 (18-100) years. The first 476 fractures were operated on by one of six surgeons with special interest in the technique, while the remaining operations were performed by any of the 35 surgeons in the department, all specialists in orthopedic surgery. Mortality within two years was 31 percent. Healing complications (redisplacement, nonunion or segmental femoral head collapse) in the total material/survivors only were for undisplaced fractures 5/7 percent, for displaced fractures 30/41 percent and for the total material 23/32 percent. According to life-table analysis, the complication rate in the total material at two years was 24 percent. The rate of secondary arthroplasty for healing complications was 13/19 percent. For displaced fractures, as well as for the total material, the group of specially interested surgeons had better results than the department as a whole.

Redisplacement of nailed femoral neck fractures. 4-year follow-up of 110 cases

In 110 femoral neck fractures, we measured the articulotrochanteric distance and the anteroposterior position of the femoral head, preoperatively, postoperatively, and at a minimum follow-up of 2 years. In displaced fractures the size of the displacement could not be used to predict future incidence of fracture redisplacement or femoral head necrosis.

Contralateral percutaneous adductor tenotomy. An aid to peroperative fluoroscopy in hip fracture fixation

In 6 elderly patients with femoral neck fractures, contralateral hip disease made lateral fluoroscopy difficult. Percutaneous adductor tenotomy of the contralateral hip facilitated screening of guide-wire placement during the fixation of the fracture.

Hook-pin fixation of subcapital fractures of the femur: an atraumatic procedure?

Eighty-seven patients with subcapital fractures of the femur treated by hook-pin fixation were reviewed clinically and radiologically with an average follow-up time of 29 months. There were 58 undisplaced and 29 displaced fractures. Seven per cent of the undisplaced and 31 per cent of the displaced fractures developed avascular necrosis (AVN) and failure of fixation was seen in 3.5 per cent and 10 per cent respectively. Overall, 23 per cent of patients developed healing complications of which just over one-half had revision arthroplasty. The AVN rate in the undisplaced group was relatively low, though there was no clear advantage over simple screw fixation. In contrast, the incidence of AVN in displaced fractures was higher than with other methods. Fixation failure was related to surgical error in most instances.

Internal fixation of femoral neck fracture. No difference between the Rydell four-flanged nail and Gouffon's pins

Two methods of internal fixation of femoral neck fractures were compared in a prospective randomized study of 223 patients. Radiographic evidence of early redisplacement, nonunion, or late segmental collapse occurred in 45 of 122 patients operated on with the Rydell four-flanged hook nail and in 33 of 101 patients operated on with Gouffon pins. According to the actuarial method of follow-up, the failure rates after 2 years were respectively 41 and 35 percent in the nail and pin groups, which is a nonsignificant difference.