Four quadrant parallel peripheral screw fixation for displaced femoral neck fractures in elderly patients

Abstract

Background:The treatment options for displaced femoral neck fracture in elderly are screw fixation, hemiarthroplasty and total hip arthroplasty based primarily on age of the patient. The issues in screw fixation are ideal patient selection, optimal number of screws, optimal screw configuration and positioning inside the head and neck of femur. The problems of screw fixation may be loss of fixation, joint penetration, avascular necrosis of femoral head, nonunion, prolonged rehabilitation period and the need for second surgery in failed cases. We hereby present results of a modified screw fixation technique in femoral neck fractures in patients ≥50 years of age.Materials and Methods:Patients ≥50 years of age (range 50-73 years) who sustained displaced femoral neck fracture and fulfilled the inclusion criteria were enrolled in this prospective study. They were treated with closed reduction under image intensifier control and cannulated cancellous screw fixation. Accurate anatomical reduction was not aimed and a cross sectional contact area of >75% without varus was accepted as good reduction. Four screws were positioned in four quadrants of femoral head and neck, as parallel and as peripheral as possible. Radiological and functional results were evaluated periodically. Sixty four patients who could complete a minimum followup of two years were analyzed.Results:Radiologically, all fractures healed after mean duration of 10 weeks (range 8-12 weeks). There was no avascular necrosis. Nonanatomical healing was observed in 45 cases (70%). All patients except one had excellent functional outcome and could do cross-legged sitting and squatting. Chondrolysis with progressive head resorption was seen in one case, which was converted to total hip arthroplasty.Conclusion:Closed reduction and cannulated cancellous screw fixation gives satisfactory functional results in large group of elderly patients. The four quadrant parallel peripheral (FQPP) screw fixation technique gives good stability, allows controlled collapse, avoids fixation failure and achieves predictable bone healing in displaced femoral neck fracture in patients ≥50 years of age.

Author’s reply

“…Only 20 “saw bone” femora were tested. With 64 patients of FNF completing 2 years of followup in our study2 and performing the same in more than 200 cases in the past 6 years without any subtrochanteric fracture, we justify FQPP screw fixation pattern.

Figure 2A line diagram showing screw head positions at the entry site for different configurations. The first picture shows horizontal configuration of three screws in cadaver settings (note the closeness of the screws; they are almost in horizontal line).

…”

“…Only 20 “saw bone” femora were tested. With 64 patients of FNF completing 2 years of followup in our study2 and performing the same in more than 200 cases in the past 6 years without any subtrochanteric fracture, we justify FQPP screw fixation pattern.…”

“…The degree of intolerance for nonanatomical reduction is unjustified in FNF cases, compared to the degree of tolerance for the same in several other fracture scenarios. Similarly, the high degree of tolerance for imperfect fixation in FNF is unjustified.We have addressed the “washers” issue earlier 10. According to us, the conclusion in that study11 was derived from a pure statistical association.…”

“…We have addressed the “washers” issue earlier 10. According to us, the conclusion in that study11 was derived from a pure statistical association.…”

Case Series of Four Quadrant Parallel Peripheral Screw Fixations for Fractured Neck of Femur and Their Outcome

“…9,10 Sathish et al 11 concluded that by adding the fourth screw and keeping the screws in peripheral portion of the head and neck, the area of fixation can be easily increased in FNFs fixation.…”