The management of severely comminuted fractures of the femoral shaft, using the external fixator

External fixation of complex femoral shaft fractures

Conversion of temporary external fixation to an intramedullary nail within the first 2 weeks after a femoral shaft fracture is standard practice. However, due to financial constraints, in large parts of the world external fixation of femoral shaft fractures is often the definitive treatment. Out of 60 fractures, 47 were followed-up for a minimum period of 39 weeks. The average follow-up time was 75 weeks. Fourteen fractures were closed, and 33 open. Forty-four fractures united at an average of 31 weeks. There were four non-unions, three of them infected. Secondary surgical procedures were performed for four non-unions and in eight cases of delayed union. One re-fracture occurred, which was successfully treated with repeat external fixation. Only six patients regained full range of motion. The average flexion was 72 degrees . Pin tract infections occurred in 26 patients, leading to loosening of four pins. Satisfactory results can be obtained with definitive external fixation of femoral shaft fractures. Pin tract infections, although a common occurrence, are not a major problem and can be treated by local wound care and antibiotic therapy. The most common problem is significant decrease in the range of motion of the knee.

[Single-plane external fixation of fresh fractures of the femur: critical analysis of 53 cases]

PURPOSE OF THE STUDY

External fixation has not been widely used for femoral fractures and few series are reported in the literature. External fixation is generally reserved for severe open fractures, for vessel injury or multiple trauma with life threatening. We present a retrospective analysis of a serie treated in a single center in order to detail the indications of this fixation technique.

MATERIAL AND METHODS

From 1984 to Jun 2002, 49 patients with femoral fractures were treated by external fixation. The series included 36 men and 13 women, mean age 31 years. All were victims of high-energy trauma: traffic accident (n = 40), fall from high level (n = 4), firearm wound (n = 5). Multiple fractures were present in all patients except seven and 24 patients had multiple injuries. Forty fractures were open fractures: two type 1, ten type 2, four type 3a, 23 type 3b and five type 3c in the Gustilo classification. Twenty-seven were shaft fractures and 26 involved the distal metaphyseoepiphyseal portion of the femur. Loss of cortical stock was noted in five cases and total loss of a segment in four. Surgery was deferred in 19 patients, mean six days. A single-plane external fixation was used (Orthofix) with a femorofemoral frontolatateral assembly. Transepiphyseal screw fixation was also used to stabilize the distal fracture in eleven cases.

RESULTS

One patient with a bifocal fracture of the femur died from head trauma. Three patients required above knee amputation after failure of a vessel bypass or due to septic necrosis of the reconstruction flap. Five patients required a second reduction within days of external fixation. On the AP view, femoral alignment was successfully reestablished at +/- 5 degrees in 45 cases, ranged from 5 degrees to 10 degrees in seven and was greater than 10 degrees in one. On the lateral view, alignment was between 5 degrees and 10 degrees in 42 cases and greater than 10 degrees in one. Femur length was equal to the healthy side in 23 cases, and was shortened 1-2 cm in 26. Four metaphyseal fractures resulted in a 3 cm shortening. Bone healing time was available for 42 patients (1 death, 3 amputations, 3 lost to follow-up). Elective conversion to internal fixation was performed in ten patients (five lateral cortical plates and five centromedullary nailings). These patients all achieved first-intention bone healing with a mean time of 7.4 months. Exclusive external fixation was planned for 34 fractures. First-intention healing was achieved in 25 (17 shaft and 8 distal) without bone graft with an average time of 7.3 months. Ten patients had one or more osteitis foci on pin tracts. Two patients in this group developed recurrent fracture after removal of the external fixator. Nine fractures did not heal and required revision with centromedullary nailing (n = 5) or plate fixation with autograft (n = 4). Nailings for nonunion were successful but plate fixation was compromised by infection in one patient and recurrent fracture after plate removal in another. Fourteen patients underwent joint mobilization under general anesthesia and 14 had open arthrolysis. Mean follow-up was 2.8 years. Mean active flexion was 90 degrees (30-130 degrees). Ten patients exhibited flexion between 30 degrees and 60 degrees and 19 between 70 degrees and 100 degrees. Knee flexion was greater than 110 degrees in 15 patients. Residual 10 degrees flexion was noted in six knees. Mean leg length discrepancy was 0.4 +/- 0.6 after distal fracture and 0.8 +/- 1.3 after diaphyseal fracture.

DISCUSSION

The indications and results of external fixation in this series are in line with reports in the literature. For diaphyseal fractures, healing is long and difficult, partly because of the insufficient mechanical properties of external fixation. The rate of infection and stiff knee is high, particularly for distal fractures of the femur.

CONCLUSION

External fixation remains the only solution to stabilize certain open diaphyseal fractures or for patients with life-threatening multiple injuries. This techniques allows control of the other traumatic lesions while waiting for internal fixation. For fractures of the distal femur, external fixation can only be advocated for metaphyseodiaphyseal fractures with an intact or reconstructed epiphyseal portion.

Effects of one-plane and two-plane external fixation on sheep osteotomy healing and complications

OBJECTIVES

Comparison of one-plane and two-plane external fixation in terms of successful healing, incidence of complications, and biomechanical stability in a sheep model.

BACKGROUND

Rigid fixation is preferred in open and comminuted fractures with a reduced blood supply, preventing infection and healing delay, but more often a flexible device is recommended even in unfavourable healing conditions.

METHODS

The left tibiae of fifteen sheep were osteotomized and laterally fixed with a four-screw unilateral fixator frame (axial stiffness 183 N/mm) to a 3 mm gap size. In 9 of 15 sheep, an additional four-screw unilateral external fixator was anterolaterally attached (total axial stiffness of both frames 388 N/mm). After sacrificing, quality of osteotomy healing was assessed by mechanical and radiological evaluations. Osteogenesis was measured using fluorescence microscopy.

RESULTS

Two distal fractures through the pin-tracks, three non-unions and four deep infections occurred after two-plane fixation. These failures excluded, osteotomy healing showed inferior results after two-plane fixation with reduced callus formation, bone mineral content, and bending stiffness amounts, respectively. Osteogenesis was halved following two-plane fixation in the remaining sheep.

CONCLUSIONS

Two-plane fixation was not sufficient to reach successful osteotomy healing in our study. While higher rigidity was expected to prevent complications, healing in this group might have been disturbed by a reduced blood supply. The optimal stabilisation for a given fracture depends on many factors, including the biomechanical and biological environment.

RELEVANCE

Considering our results and the literature discussed in this manuscript, good bone healing with minor risks of infections can be achieved using an unilateral one-plane fixator with only four screws, and its application on a muscle free position like the medial and anterior site of the sheep tibia.

Performance of external fixation devices in femoral fractures; the ultimate challenge? A laboratory study with plastic rods

Whether or not external fixation should be applied to the femur, and on what grounds, will depend upon a variety of factors. It is rarely considered to be the treatment of first choice. External fixation can, however, be indicated in certain circumstances. Looking for optimal rigidity in such cases we tested and compared the stability of 14 different femoral external fixators in an experimental model. It was found that the weight of the different frames varied from 400 to 2000 g. The comparative stability also varied widely. Movements of between 1 mm and 4 cm and rotations varying from almost 0 degrees to 16 degrees were measured at the (experimental) fracture site, based upon the geometry of an adult patient. In view of this finding primary bone-healing would not be expected to occur, since it demands more stability than external femoral fixation can offer. A relatively simple two-dimensional (unilateral) frame can be as rigid as a three-dimensional one, in response to all but transverse loading.

Cerclage wiring in the management of comminuted fractures of the femoral shaft

A retrospective series of 20 patients is presented, comprising 21 fractures of the femoral shaft treated by open reduction and internal fixation (usually by medullary nailing) combined with cerclage wiring. Most of the patients were young with comminuted fractures of the femoral shaft, many with multiple injuries. The aims of stable reduction and early sound union of the fracture in anatomical position were achieved in all cases and that of early mobilization of the knee to a good ultimate range of flexion in almost all cases.