Iatrogenic femoral neck fracture: an unusual cause

INTRODUCTION

Intramedullary nailing is currently a common method of closed internal fixation of diaphyseal fractures in long bones.¹ However, this technique is not devoid of complications.² Among these, the iatrogenic fracture of the femoral neck - during anterograde intramedullary nailing of the femur - is rarely reported in the literature and remains little known.² There are only 25 cases in which the authors mainly incriminate a misplaced introduction point.

In this paper, the authors report a case of iatrogenic fracture of the femoral neck whose cause has never been described.

CASE REPORT

A 29-year-old patient, right-handed, driver of military heavyweight vehicles, with no notable antecedents, no smoking, admitted to the emergency department following a road accident.

Clinical examination revealed a swelling right thigh with pain in palpation. The cutaneous and vasculo-nervous examinations were normal as well as examination of ipsilateral knee and hip.

X-rays revealed an oblique fracture of the femoral diaphysis with a third fragment (Figure 1). The ipsilateral hip X-rays were normal.

The intramedullary nailing was decided and performed in the same day. After locoregional anesthesia and installation on orthopedic table, fluoroscopic incidences of the femoral diaphysis were performed to verify the reduction of the fracture but also the state of the proximal and distal femoral epiphysis in search of associated fracture line.

During the procedure, trepanation was performed at the pisiform fossa under fluoroscopic control, successful at the first attempt. The passage of the guide rod and reamers with ascending diameter to size 12, 5 was achieved without difficulty. The introduction of the nail diameter 11 was performed without impaction. The difficulty arose with the proximal screwing. It was necessary to perform some impactions. The introduction of this screw was blocked despite proper drilling and tapping.

The postoperative X-rays revealed the occurrence of a femoral neck fracture; the fracture line was distant from the point of introduction of the nail (Figure 2). The patient was reopereted the next day by the placement of a femoral reconstruction nail with 2 cervical screws (Figure 3).

Both fractures consolidated after 5 months. Total foot support was authorized in the 6 months and a return to previous activities after 7 months. At the last follow-up of 14 months, the patient had no clinical or radiological abnormalities (Figure 4).

DISCUSSION

Intramedullary nailing of the femur has become a common treatment of diaphyseal fractures and even a treatment of choice given many advantages such as conservation of the fracture hematoma and the reduction of the risk of infection. However, like any surgical procedure, it exposes to other known risks such as rotational disorders, nonunion and other rare risks like iatrogenic fractures of the femoral neck.^3,4

The iatrogenic fracture of the femoral neck during the femoral nailing remains a little-known complication and is rarely reported in the literature. We found only 25 cases reported (Table 1).

This complication is confusing with the femoral neck fracture associated to femoral diaphysis fracture. Indeed, this association appears in 2.5% to 6% of cases of femoral diaphyseal fractures and is diagnosed late in 19% to 31% of cases.¹⁰ Yang et al describe that X-rays is insufficient to detect an occult non displaced fracture of the femoral neck and propose the realization of a tomodensitometry of the hip or a fluoroscopic examination before the surgical act.⁸ In our case, this possibility of confusion has been ruled out by performing a digital good quality X-rays as well as fluoroscopic front and side views before surgery.

Although this intraoperative complication is poorly described, several authors have studied the issue and have tried to advance theories to avoid this incident. Harper reported 2 cases and relates this complication to the wrong direction of the nail during the introduction.⁵ Christie in his retrospective study reporting 4 cases on a series of 143 femoral nailing, links this incident to a lateral introduction point in the trochanteric region obliging the operator to introduce the nail obliquely.³ Simonian described 4 cases in a series of 315 femoral nailing and based on Miller's cadaveric studies to incriminate an anterior introduction point; he also identified the impaction of the prominent edge of the nail on a valgum neck (cervico-trochanteric angle greater than 135°) as the cause of this type of complication.^7,11 Khan described 3 cases and incriminates the forced use of the curved awl in the wrong direction and the realization of multiple entry points.⁴ Castellanos described 4 cases in a series of 494 nailing and insists that the introduction of the nail from the pisiform fossa would be more adequate than the top of the greater trochanter.¹⁰

Thus, we found that in the majority of the writings, the authors revolve around errors related to the point of initial introduction or the introduction of the nail. But it also seems likely that the iatrogenic fracture of the cervix is not entirely due to an inappropriate point of introduction, excessive insertion depth, an oblique nail, or nail impaction. Deep and Apivatthakakul each reported respectively a clinical case related to the removal of a broken reamer and the insertion of a nail with inverted curvature.^1;2 In the case we report here, the point of introduction was well at the level of the pisiform dimple and the nail was introduced without impaction. The difficulty arose during the setting up of the proximal locking screw requiring some impactions, which suggests that this is the cause of the iatrogenic fracture of the femoral neck. This has never been described.

CONCLUSION

Intramedullary nailing as a treatment for femoral diaphyseal fractures remains a treatment of choice, however the surgeon must keep in mind that such complication can occur during all stages of nailing and that he must be vigilant and respect all steps of this procedure. We propose to avoid the kind of maneuver that can cause iatrogenic fracture of the femoral neck. A reboring of the cervical screw path would be more suitable and will avoid this incident.

Funding: No funding sources

Conflict of interest: None declared

Ethical approval: Not required

REFERENCES

1. 1. Apivatthakakul T, Arpornchayanon O. Iatrogenic femoral neck fracture caused by mal-insertion of a curved intramedullary nail. Injury. 2001;32(9): 727-9.
2. 2. Deep K, Sharp I, Hay SM. Femoral neck fracture complicating intramedullary nailing of femoral shaft: a case report. Injury. 1999;30(6):445-7.
3. 3. Christie J, Court-Brown C. Femoral neck fracture during closed medullary nailing: brief report. J Bone Joint Surg Br. 1988;70(4):670.
4. 4. Khan FA, Ikram MA, Badr AA, Al-Khawashki H. Femoral neck fracture: a complication of femoral nailing, Injury. 1995;26(5):319–21.
5. 5. Harper MC, Henstrof J. Fractures of the femoral neck associated with technical errors in closed intramedullary nailing of the femur. J Bone Joint Surg Am. 1986;68(4):624-6.
6. 6. Böstman O, Varjonen L, Vainionpää S, Majola A, Rokkanen P. Incidence of local complications after intramedullary nailing and after plate fixation of femoral shaft fractures. J Trauma. 1989;29(5):639-45.
7. 7. Simonian PT, Chapman JR, Selzuick HS, Benirschke SK, Claudi BF, Swiontkowski MF. Iatrogenic fracture of the femoral neck during closed nailing of the femoral shaft. J Bone Joint Surg Br. 1994;76(2):293-6.
8. 8. Yang KH, Han DY, Park HW, Kang HJ, Park JH. Fracture of the ipsilateral neck of the femur in shaft nailing. The role of CT in diagnosis. J Bone Joint Surg Br. 1998;80(4):673–8.
9. 9. Bonnevialle P, Glasson JM, Determe P, Bellumore Y, Mansat M. Iatrogenic cervical fracture after femoral diaphyseal nailing. Rev Chir Orthop Reparatrice Appar Mot. 1999;85(4):397–403.
10. 10. Castellanos J, Garcia-Nuño L, Cavanilles-Walker JM, Roca J. Iatrogenic Femoral Neck Fracture During Closed Nailing of the Femoral Shaft Fracture. Eur J Trauma Emerg Surg. 2009;35(5):479–81.
11. 11. Miller SD, Burkart B, Damson E, Shrive N, Bray RC. The effect of the entry hole for an intramedullary nail on the strength of the proximal femur. J Bone Joint Surg Br. 1993;75(2):202-6.