Rigid osteosynthesis decreases the late complication rate after femoral neck fracture. The influence of three different osteosynthesis devices evaluated in 369 patients

Surgical management of bifocal femoral fractures: a systematic review and pooled analysis of treatment with a single implant versus double implants

INTRODUCTION

Fractures of the proximal femur accompanied by a fracture of the femoral shaft are relatively rare, with a reported prevalence between 1 and 12%. Multiple surgical options are available, consisting of treatment with a single implant or with double implants. Controversy exists about the optimal management. A systematic review and pooled analysis were performed to assess the most reliable treatment for bifocal femoral fractures of the femur.

MATERIALS AND METHODS

A literature search was conducted on July 15, 2022. Selected studies were screened on title and abstract by two researchers independently, and full texts were read by both authors. Emphasis was put on adverse events such as postoperative infection, healing complications, malalignment, and functional outcome using either a single implant or double implants.

RESULTS

For the proximal femoral fractures, no significant difference could be confirmed for avascular necrosis of the femoral neck (5.1% for single implant and 3.8% for double implants), nonunion (6.4% for single implant and 7.8% for double implants), or varus malalignment (6.6% for single implant and 10.9% for double implants). This study also suggests that the number of implants is irrelevant for complications of the femoral shaft regarding the rates of postoperative infection and healing complications. Pooled rates of bone healing complications were 1.6-2.7-fold higher when patients were treated with a single implant, but statistical significance could not be confirmed. For hardware failure, revision surgery, leg length discrepancy, and functional outcome, no difference between the two groups was found either.

CONCLUSIONS

The pooled proportions of all postoperative complications had overlapping confidence intervals; thus, no inference about a statistically significant difference on the number of implants used for treating ipsilateral fractures of the femur can be made. Both treatment groups showed a similar functional outcome at the last moment of follow-up, with more than 75% of the patients reporting a good outcome.

Biplane double-supported screw fixation (F-technique): a method of screw fixation at osteoporotic fractures of the femoral neck

The present work introduces a method of screw fixation of femoral neck fractures in the presence of osteoporosis, according to an original concept of the establishment of two supporting points for the implants and their biplane positioning in the femoral neck and head. The provision of two steady supporting points for the implants and the highly increased (obtuse) angle at which they are positioned allow the body weight to be transferred successfully from the head fragment onto the diaphysis, thanks to the strength of the screws, with the patient’s bone quality being of least importance. The position of the screws allows them to slide under stress with a minimal risk of displacement. The method was developed in search of a solution for those patients for whom primary arthroplasty is contraindicated. The method has been analysed in relation to biomechanics and statics. For the first time, a new function is applied to a screw fixation—the implant is presented as a simple beam with an overhanging end.

Valgus intertrochanteric osteotomy with single-angled 130° plate fixation for fractures and non-unions of the femoral neck

Non-union of femoral neck fractures may occur due to mechanical and biological factors. Valgus intertrochanteric osteotomy (VITO) alters hip biomechanics and enhances fracture union. The double-angled 120° plate is usually used for internal fixation of the osteotomy. It allows the osteotomy to heal with medialisation and verticalisation of the femoral shaft. This deformity causes medial ligament strain of the knee joint, genu valgum and ultimately osteoarthritis. This work presents our experience in treating vertical fractures and non-unions of the femoral neck by VITO and fixation by a single-angled 130º plate. Thirty-six patients presented with 19 recent vertical femoral neck fractures, and 17 non-unions were included. They were 26 men and ten women, and their ages averaged 37 years. Preoperative planning and VITO technique are described. Union was achieved in 35 patients (97%), and one recent fracture failed to unite (3%). Time to fracture union averaged four months in recent fractures and eight months in un-united fractures. All patients with united fractures had an almost normal configuration of the upper femur. Avascular necrosis of the femoral head was reported in five patients. Twenty-two patients (61%) were pain free, nine (25%) had hip pain on lengthy walks and the remaining five (14%) had persistent pain. Preoperative limb shortening averaged 2.5 cm, and post-operative shortening averaged 0.5 cm. We recommend VITO and fixation by a single-angled 130º plate for vertical femoral neck fractures and non-unions in relatively young adult patients.

VALGUSING INTERTROCHANTERIC OSTEOTOMY FOR THE TREATMENT OF FEMORAL NECK NON-UNIONS: REPORT OF 32 CASES

The purpose of the present study was to review the results of femoral neck non-unions treatment with valgusing intertrochanteric osteotomy.

METHODS

Between 1988 and 2003 we treaded thirty two femoral neck non-unions with valgusing osteotomy and fixation. The mean follow-up time was 9.8 years and the mean age was 41.7 years.

RESULTS

Twenty eight (87.4%) of the thirty two valgusing osteotomies evolved to femoral neck union, while four cases (12.6%) evolved to total hip arthroplasty. Eight cases evolved to partial osteonecrosis.

CONCLUSIONS

The valgusing intertrochanteric osteotomy for treating femoral neck non-unions achieved consolidation in 87.4% (28/32). However, only 56.2% (18/32) achieved full recovery of hip function.

More than two years delay in the union of fracture neck of femur after primary intervention

Introduction

More than two years delay in the union of fracture neck of femur is a very rare entity.

The treatment of an established non union depends on numerous factors including age of the patient, vascularity of the femoral head and other factors. It is timing of intervention that is not clearly defined in the literature.

Case presentation

We report 2 cases where fracture neck of femur in 2 Asian males of 37 and 52 years of age took more than 2 years to unite after primary intervention.

Conclusion

We believe if the implant is holding and patient is able to bear some weight, some of these fractures may unite without any further intervention.

Osteosynthesis and primary valgus intertrochanteric osteotomy in displaced intracapsular fracture neck of femur with osteoporosis in adults

Fifty-three adults sustaining intracapsular femoral neck fractures (subcapital 38 and transcervical 15) with osteoporosis were treated primarily by osteosynthesis with valgus intertrochanteric osteotomy. Final evaluation was done in 50 patients (1 patient died and 2 lost to follow up, were not considered). Union was achieved in 47 (94%) patients in an average period of 12.2 weeks (range 10-18 weeks) with 100% union at osteotomy site. An axial collapse between 2 and 14 mm was observed in 74% of patients at the fracture site. Average neck shaft angle achieved was 141 degrees . Retroversion of the femoral head was seen in 28% of patients postoperatively, but none demonstrated a further posterior tilt of proximal femoral fragment, thus preventing implant cut through. One of the four patients with avascular necrosis of the femoral head exhibited late segmental collapse between 98 and 171 weeks. Final results were excellent to good in 76% of patients (average hip score 92), fair in 18% (average Harris hip score 73) and poor in 6% (average Harris hip score 30). Deep infection in 2%, superficial infection in 4%, implant penetration into the joint in 4%, limb length discrepancy in 6% and external rotation in 68% were other complications. Primary osteosynthesis with valgus intertrochanteric osteotomy is a dependable procedure to provide stable fixation in fresh fractures of the neck of femur with osteoporosis. The potential benefit of retaining a viable biologic joint justifies the usefulness of this procedure.

Femoral neck fractures in older patients: indication for osteosynthesis

In almost all the patients over 65 years of age with intracapsular femoral neck fractures who we treated over a 2-year period, we used osteosynthesis with Ace 6.5-mm cannulated cancellous screws. We then followed them for at least 24 months. Each of the seven nondisplaced fractures healed. Of the 20 displaced fractures, 14 were rated as healed, 5 as failures, and 1 as a late segmental collapse. Among the 14 displaced fractures with an operative delay of 1 day, 12 healed, whereas only 2 of the 6 fractures with an operative delay of 2 days or more did so. Of the 12 typical fractures (with a medial spike in the head fragment), 10 healed, as did 4 of the 8 crescent or mixed-type fractures. The treatment of choice for nondisplaced fractures is osteosynthesis. Displaced fractures that occur on the day of operation or the day before should be treated with osteosynthesis if they are the typical type. The rest of the displaced fractures should be considered candidates for primary prosthetic replacement.

The treatment of nonunion after intracapsular fracture of the proximal femur

Nonunion is a frequent complication of displaced intracapsular fractures of the femoral neck and occurs in as many as 43% of patients. The incidence can be reduced by prompt anatomic reduction and stable fixation. The treatment of an established nonunion depends on numerous factors including the age of the patient, the vascularity and sphericity of the femoral head, alignment of the neck and shaft, and potential limb length discrepancy. An algorithm constructed from literature-based evidence of the results of available procedures for treatment of nonunion is presented and the roles of refixation, osteotomy, grafting, and prosthetic replacement are considered.

Mechanobiology of initial pseudarthrosis formation with oblique fractures

Mechanical stresses play an important role in regulating tissue differentiation in a variety of contexts during skeletal development and regeneration. It has been shown that some intermittent loading at a fracture site can accelerate secondary fracture healing. However, it has not been shown how the stress and strain histories resulting from mechanical loading of a fracture might, in some cases, inhibit normal fracture healing and induce pseudarthrosis formation. In this study, finite element analysis is used to calculate hydrostatic stress and maximum principal tensile strain patterns in regenerating tissue around the site of an oblique fracture. Using a mechanobiologic view on tissue differentiation, we compared calculated stress and strain patterns within the fracture callus to the histomorphology of a typical oblique pseudarthrosis. Tissue differentiation predictions were consistent with the characteristic histomorphology of oblique pseudarthrosis: in the interfragmentary gap. tensile strains led to "cleavage" of the callus; at the ends of both fracture fragments, hydrostatic pressure and tensile strain caused fibrocartilage formation, and, at discrete locations of the periosteum at the oblique fracture ends, mild hydrostatic tension caused bone formation. We also found that discrete regions of high hydrostatic pressure correlated with locations of periosteal bone resorption. When previous findings with distraction osteogenesis are considered with these observations, it appears that low levels of hydrostatic pressure may be conducive to periosteal cartilage formation but high hydrostatic pressure may induce periosteal bone resorption during bone healing. We concluded that tissue differentiation in pseudarthrosis formation is consistent with concepts previously presented for understanding fracture healing, distraction osteogenesis, and joint formation.

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.