International Journal of Orthopaedic Surgery

: 2021  |  Volume : 29  |  Issue : 2  |  Page : 58--60

Bilateral floating knee treated by intramedullary nailing on orthopedic table: A case report with review of literature

Omar Lazrek1, El Mehdi Sabri1, Moncef Boufettal2, Bassir Rida Allah2, Moulay Omar Lamrani1, Mohammed Kharmaz1, Mustapha Mahfoud1, Ahmed Bardouni1, Mohamed Salah Berrada1,  
1 Department of Traumatology and Orthopedic Surgery Hospital IBN SINA, Rabat, Morocco
2 Department of Traumatology and Orthopedic Surgery Hospital IBN SINA, Rabat, Morocco; Laboratory of Anatomy, Faculty of Medicine Rabat, University Med V Rabat, Rabat, Morocco

Correspondence Address:
Omar Lazrek
Department of Traumatology and Orthopedic Surgery Hospital IBN SINA, km7 route meekness, villa oumnia, salé, Rabat.


Floating knee is a lesion entity first described in 1975 by Blake and McBride. Bilateral involvement is exceptional. It occurs for high-energy trauma and is usually accompanied by other potentially life-threatening lesions. Our patient presented a trauma of lower limbs following a motorcycle accident. The clinically evoked diagnosis was confirmed after standard radiological assessment.

How to cite this article:
Lazrek O, Sabri EM, Boufettal M, Rida Allah B, Lamrani MO, Kharmaz M, Mahfoud M, Bardouni A, Berrada MS. Bilateral floating knee treated by intramedullary nailing on orthopedic table: A case report with review of literature.Int J Orthop Surg 2021;29:58-60

How to cite this URL:
Lazrek O, Sabri EM, Boufettal M, Rida Allah B, Lamrani MO, Kharmaz M, Mahfoud M, Bardouni A, Berrada MS. Bilateral floating knee treated by intramedullary nailing on orthopedic table: A case report with review of literature. Int J Orthop Surg [serial online] 2021 [cited 2023 Mar 26 ];29:58-60
Available from:

Full Text


Floating knee is a lesion entity described in 1975 by Blake and McBride.[1] It is the association of a femur fracture with an ipsilateral fracture of the tibia. This lesion isolates the knee from the rest of the limb. Bilateral floating knees are rarely observed in orthopedic practice. Fraser’s classification distinguishes four types of floating knee, depending on the seat of the fractures. The treatment is surgical and several means of osteosynthesis are possible. The complications are frequent, first of a general nature which can cause the death of the patient (fatty embolism, pulmonary embolism, associated lesions), and local (infection, malunion, nonunion, knee stiffness). In our patient, we opted before the seat of the fractures for nailing femurs (anterograde) and shins is seen. The purpose of this paper is not only to report this rare entity but also to review the literature.

 Case Report

It is the observation of a 21-year-old woman who is polytraumatized and a victim of an accident of the public road (motorcycle accident) with cranial impact point, pelvis, and the two lower limbs, with the following clinical examination: deformation of both thighs and legs, no cutaneous opening, and peripheral pulses were present. The radiograph shows a fracture of the right obturator frame with bilateral floating knees and a fracture of the right medial malleolus [Figure 1]. The patient was treated in surgical resuscitation and operated after hemodynamic stabilization by intramedullary nailing of two tibias and two femurs on orthopedic tables with concomitant bilateral traction and cradling stays of the internal malleolus [Figure 2]. The evolution at 18 months was marked by a complete resumption of walking without crutches, a consolidation of different fracture centers.{Figure 1} {Figure 2}


Bilateral floating knees are rare. Only three cases are found in the literature from 1969 to 2011. Mechanism of the trauma is poorly described. As with our patient, it is a polytrauma in 37% of cases according to Fraser et al.,[1] and 14.2% have severe head trauma.[2]

On the nosological plane, type I extra-articular floating knees are much more common than their type II joint variations in all non-exclusive series, especially for bilateral floating knees; or two out of three series are type I.[3]

Fracture consolidation remains a problem with the existence of nonunion on a fracture site in 20% of the cases. Although the rate of nonunion has decreased with nailing, it varies in series from 4% to 11% for the femur and from 3% to 30% for the tibia. The factors involved in the consolidation are age, sex, type of knee floating, the seat (distal femur, diaphyseal tibia).

Rethnam et al.[4] conducted a 3-year prospective study on 29 patients. They recommend treatment with anterograde intramedullary nailing, except in cases of severe open fracture. Currently, the recommended treatment for type I floating knee with diaphyseal fracture uses double emergency nailing.[5],[6] Some teams recommend antebral nailing for the tibia and retrograde nailing for the femur.[4]

In our exceptional case with the simultaneous presence of bilateral floating knee, the treatment consisted of closed antegrade closure of the two diaphyseal fractures, tibia and femur, with bilateral traction on the orthopedic table; the image intensifier was placed between the limbs. Due to the speed of management of both floating knees, the patient did not present any serious peri- or postoperative complication and the evolution to date is satisfactory.


Bilateral floating knee is underreported in the literature. Rapid and concomitant management of both limbs is essential. The femoral fixation of first intention is the recommended attitude. However, the first tibial fixation is preferred in the event of significant decay or ischemia of the leg as well as in the bilateral knees floating.

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.


1Fraser RD, Hunter GA, Waddell JP. Ipsilateral fracture of the femur and tibia. J Bone Joint Surg Br 1978;60-B:510-5.
2van Raay JJ, Raaymakers EL, Dupree HW. Knee ligament injuries combined with ipsilateral tibial and femoral diaphyseal fractures: The “floating knee.” Arch Orthop Trauma Surg 1991;110:75-7.
3Rios JA, Ho Fung V, Ramirez N, Hernandez R. Floating knee injuries treated with a single incision technique versus traditional antegrade femur fixation: A comparative study. Am J Orthop 2004;33:468-72.
4Rethnam U, Yesupalan RS, Nair R. The floating knee. Epidemiology, prognostic indicators and outcome following surgical management. J Traum 2007;1:1-8.
5Bonnevialle JP, Kany J, Samaran P, Pascal JF, Rongiers M, Leininger P, et al. Fractures associées homolatérales diaphysaires fémorale et tibiale. Rév Chir Orthop1993;79:55-9.
6Oh CW, Oh JK, Min WK, Jeon IH, Kyung HS, Ahn HS, et al. Management of ipsilateral femoral and tibial fractures. Int Orthop 2005;29:245-50.