Bilateral Concomitant Open Distal Femur Fractures Associated with Bilateral Quadricipital Tendon Rupture: A Case Report

Fractures of the distal femur present 3–6% of all femoral fractures with 5–10% being open [1, 2]. This injury has a high incidence in young males who are involved in high-energy trauma [3] and old women due to bone fragility [4]. These fractures are often intra-articular and comminuted and understanding its characteristics is crucial to optimize the outcome [4].

Various associated injuries such as ipsilateral femoral neck, intertrochanteric, acetabular, tibial plateau, patellar, and phalangeal fractures [1] can be found depending on the mechanism of injury. In addition, soft tissue afflictions such as ACL ruptures and vascular injuries are also reported [1].

Herein, we present the case of a patient presenting with concomitant bilateral open distal femur fractures and bilateral rupture of the quadriceps tendons. As per the review of literature and to the best of our knowledge, this is the first case reporting a combination of such injuries.

A 45-year-old male patient was admitted to our emergency department for management of bilateral lower limbs trauma after a fall from the third floor during a fire escape. He landed on a sleeping mattress on flexed knees collapsing on his hands and chest. He was found to have bilateral open fractures of the distal femurs, with the right femur having a C3.3 and the left femur an A3.3 OA/OTA fracture pattern (Fig. 1), associated to multiple stable vertebral and costal fractures with no sensorimotor deficits, with an APACHE II score of five. The lacerations and open wounds on both sides were type III Gustilo Anderson injury patterns.

He was taken to the operating room for open reduction internal fixation of his bilateral fractures. The lacerations were cleaned thoroughly with lavage, betadine, and hydrogen peroxide. Wounds were extended proximally and laterally, establishing a lateral approach to the distal femur. Dissection was performed until reaching the articular surface distally and reflecting the vastus lateralis proximally. Starting with the right side, the comminuted distal femur fracture was identified. The condylar fracture was addressed first and fixed with two compression screws placed anterolaterally to antero-medially with fluoroscopic assessment of the involved articular surface. Going proximally to the comminuted distal femur shaft, reduction was maintained using bone holding forceps and the distal fragment was fixed using a lag screw. The pin for the distal central 8-mm screw was inserted and a 15-holes anatomical locking compression plate (LCP) was placed and fixed at the condylar screw site. Traction alongside control on alignment and rotation was done with satisfactory results by holding the proximal part of the plate to the proximal fragment via a bone holding forceps. The plate was fixed with six proximal and five distal locking screws. The same procedure was done on the left side without articular involvement. During the surgery, both quadriceps tendons were found to be ruptured. It was a cleanly lacerated full thickness tear. Two number 5 nonabsorbable sutures, using the Krackow stitch were utilized to repair both tendons. The superior poles of the patella were debrided to expose the bone and with a 2.5-mm drill, 3 longitudinal holes were created in the patella, medial, middle, and lateral. The sutures were passed through the holes and were tied while placing the knee in full extension. Long leg bivalve casts were placed bilaterally, and complete immobilization was kept for 6 weeks after which casts were replaced with extension knee braces. At 1-month follow-up, radiographs of both femurs were done showing adequate alignment (Fig. 2). Physical therapy in bed was started after 6 weeks, consisting of bilateral quadriceps strengthening and continuous passive range of motion 0–40° that was advancing slowly as tolerated till reaching full range of motion. Weight-bearing was initiated at 18 weeks postoperatively.

The patient had a slow progressive recovery after which he was able to achieve full range of motion alongside the ability to ambulate. However, 6 months postoperatively, delayed union was noticed at the right metaphyseal-diaphyseal junction fracture, where healing was absent on three cortices. After observation for 1 year, injection of mesenchymal cells from the iliac crest was performed percutaneously under fluoroscopic guidance. At 14 months postoperatively, the patient presented with acute severe pain of the right femur and investigations showed a failure of the hardware that was due to the nonunion (Fig. 3). He was then admitted for surgical management where an anterior bridge plate was placed, fixed with three proximal and three distal screws. The old LCP is removed, the nonunion site debrided, and a new LCP was placed with seven proximal (6 locking and 1 compression) and five distal screws. Right iliac crest autograft was placed at the fracture site. After the re-do osteosynthesis, uneventful recovery was noted, and the patient showed radiographic and clinical evidence of healing with no complications (Fig. 4). After 4 years of follow-up, bilateral complete healing with a normal function of both lower limbs and a normal gait were achieved (Fig. 5). Removal of hardware from both femurs was later done with radiological and surgical signs of bony healing (Fig. 6, 7).

Various associated injuries are described with distal femur fractures; however, rupture of the quadriceps tendon is a rare association. A case report by Calmet et al. [5] describes two cases of Hoffa-type distal femur fractures with injury to the extensor mechanism. One of them is a quadriceps tendon rupture, while the other is a patellar tendon injury. According to our extensive literature review, bilateral quadriceps rupture associated to a bilateral distal femur fracture has not been previously reported in the literature. A post-traumatic bilateral transphyseal fracture of the femur was also reported in the literature due to a mechanism involving hyperextension of both knees [6].

As for the fracture displacement, it is affected by three main forces: the quadriceps tendon, the gastrocnemius, and the adductor muscles. The axial pull of the quadriceps tendon mainly leads to shortening. The gastrocnemius muscle pulls the distal fragment into flexion, and the adductors lead to varus displacement [7]. In our case, the quadriceps tendon did not have a role in the displacement which may have led to this abnormal displacement.

Being a post-traumatic fracture, nonunion is more prone to occur than in a non-post-traumatic fracture due to the higher rates of metabolic demands by the patient [8]. Risk factors of nonunion in distal femur fractures include open fractures, bone loss, infection, broken implants, loss of fracture reduction, stiff construct, and excessive shearing stress [9]. It can usually be prevented by avoiding stiff constructs and the use of gross autograft bone may be beneficial [9]. An infection may have been the cause of nonunion in our patient, but it is unlikely since asepsis was maintained throughout the whole operation, and casts were applied later on. In fact, since the nonunion occurred in only one leg and the same construct was done in both legs, nonunion could have been caused by a higher bone loss in the affected leg or a loss of reduction since it was done at first. The construct could not be the reason since it is applied on the left side as well. If a single lateral plate was used, the risk of nonunion would have been much higher. The definitive treatment in these cases with a medial bone loss of more than 2 cm would be a medial plate augmentation with bone grafting [10].

Classifying this fracture is an important prerequisite in order to devise the best management. Several classifications are available for distal femur fractures, among which are Neer’s classification, Seinsheimer classification, and the AO classification which is currently the gold standard. The AO classification is based on Muller’s classification, which is based on the anatomic relation to the articular surface [7]. The fractures are divided as extra-articular (type A), partial articular (type B), and complete articular with bicondylar detachment (type C) [7] with a different treatment for each one [4].

The treatment being usually surgical may also be conservative [5]. Before the treatment, a complete trauma evaluation is very important and after that the treatment usually begins with an external fixation in open fractures and ends most of the time with a permanent internal fixation [4]. In the case reported by Calmet et al. [5], internal fixation using 4 cancellous lag screws was performed due to the fracture being open and associated with extensive soft tissue injury. Other treatments of supracondylar distal femur fracture include flexible intramedullary nails [11], plate fixation [12] using condylar plates, locking plates or blade plates [4], buttress plates with screws, total knee arthroplasty which is attempted in osteoporotic patients with severe comminuted fracture or preexisting arthritis [4] and distal femur replacement in patients with a previous total knee replacement [13]. The selection of the definitive fixation is based on the patient’s status and the characteristics of the fracture. In this case, the decision to undergo osteosynthesis was taken intraoperatively when it was feasible to adequately decontaminate the soft tissue with acceptable coverage rendering it a single-stage surgery, taking into consideration femur involvement, patient age, and severe injuries.

In similar cases such asfloating knee injuries where injury to both the femur and tibia occur in the same knee, the timing of treatment should be a case-by-case matter. However, the surgical sequence must be the same starting with the femur fixation followed by the tibia stabilization taking into account the condition of the skin as well as focusing on the reduction of complications as their rate is high during such operations [14, 15]. In long bone open fractures such as this case, a feasible alternative to amputation and bone transport especially if the fragment is major portion of a joint would-be sterilization and reimplantation of autograft as this technique allows a more physiological return to daily activities [16].

This is the first case of bilateral concomitant open fractures of the distal femur with bilateral rupture of the quadriceps tendons. One of the most important things when dealing with traumatic cases is achieving a sterile wound site in order to reduce the risk of infection. A lot of fixation techniques may be suitable but patients presenting with traumatic contexts have multiple injuries most of the time which may induce a higher biological and metabolic demand for than patients with isolated injuries. The use of biological supplementations such as aspirated autograft cells or gross autograft bone initially may be beneficial in preventing nonunion.

This study protocol was reviewed and approved by Saint George’s Hospital Ethics Committee on September 2021. Written informed consent was obtained from the patient for publication of the details of their medical case and any accompanying images.

The authors have no conflicts of interest to declare.

No funding was received for this study.

Mohammad Darwish and Dany Aouad: data collection and writing; Elias Saidy and Jamal Saade: writing; Georgio lati: writing and revision; Mohammad Daher: writing and submission; Alexandre Nehme: surgeon who did the surgery and final review.

All data that support the findings of this study are included in this article.