The Pediatric "Floating Knee" Injury: A State-of-the-Art Multicenter Study

Pediatric floating knee injuries: Clinical modifiers affecting sports and transfer outcomes

AIM

This study assessed the functional outcome, and the clinical modifiers that influence them with the aim to assist the clinician plan a better management strategy in Paediatric Floating Knee (PFK) injuries.

METHODS

A quasi-prospective, single-center observational study was designed to determine the functional and radiological outcomes in children (

RESULTS

Of 32 patients with PFK injury, twenty-five patients with a mean follow-up of 43 months (SD = 18) who completed the PODCI questionnaire were analysed. Fourteen (56%) children had open fractures (Lett's D or E types) with 6 open femur and 12 open tibia fractures. Majority underwent surgical fixation, 8 children required staged reconstruction and 11 children required soft tissue procedure in the ipsilateral limb. The mean time to union for femur and tibia fractures was 3.86 months (SD = 5.3) and 3.5 months (SD = 2.9), respectively with delayed union/non-unions in 3 femoral and 4 tibial fractures. The mean knee range of movement (RoM) was 102° (SD = 34.1) with limb shortening in 6 children, and overgrowth in 3 children. The mean normative PODCI (transfer) score was 35.6 (normal range: -74 to 52) and mean PODCI (sports) score was 37.6 (normal range: -33 to 56). Both the PODCI scores demonstrated strong inverse correlation with higher ISS(p < 0.01) and > 4 cm of bone loss (p < 0.01) but poor correlation with age at injury (p = 0.5), open fracture (p = 0.17), comminuted femoral and/or tibial fracture patterns (p > 0.05) and loss of soft tissue cover (p = 0.08).

CONCLUSIONS

Early recognition of clinical modifiers such as high ISS and bone loss > 4 cm warrants targeted limb reconstruction strategy and can help to prognosticate outcome.

Collapse

Key Words

• Clinical modifiers
• Functional outcome
• Letts classification
• PODCI
• Pediatric floating knee injury

Collapse

MESH Headings

• Child
• Humans
• Fractures, Open/diagnostic imaging
• Fractures, Open/surgery
• Knee Injuries/diagnostic imaging
• Knee Injuries/surgery
• Lower Extremity
• Prospective Studies
• Retrospective Studies
• Tibial Fractures/diagnostic imaging
• Tibial Fractures/surgery
• Treatment Outcome
• Adolescent

Collapse

Grants Collapse

Affiliation(s)

Sagar Tontanahal Department of Paediatric Orthopaedics, No. 1106, Paul Brand Building, Christian Medical College, Vellore, 632004, India
Deeptiman James Department of Paediatric Orthopaedics, No. 1106, Paul Brand Building, Christian Medical College, Vellore, 632004, India
Abhay Gahukamble Department of Paediatric Orthopaedics, No. 1106, Paul Brand Building, Christian Medical College, Vellore, 632004, India
Vrisha Madhuri Department of Paediatric Orthopaedics, No. 1106, Paul Brand Building, Christian Medical College, Vellore, 632004, India
Thomas Palocaren Department of Paediatric Orthopaedics, No. 1106, Paul Brand Building, Christian Medical College, Vellore, 632004, India.

Collapse

Bilateral floating knee injury in a child with down syndrome: A case report

INTRODUCTION AND IMPORTANCE

Floating knee injury is a rare injury that involves a simultaneous fracture of the femur and tibia. It is more common among young men and is generally caused by high-speed blows. Down syndrome is a chromosomal disorder associated with various musculoskeletal conditions. Children with Down syndrome have generalized ligamentous laxity, joint hypermobility, and hypotonia, leading to musculoskeletal conditions such as atlantoaxial instability, hip instability, and patellar instability.

CASE PRESENTATION

A 10-year-old boy with Down syndrome was admitted to the emergency room due to a car accident. Radiographic examinations revealed a diaphyseal fracture of the right femur and a diaphyseal open fracture of the tibia compatible with floating knee injury Type-D, and a physeal fracture of the distal femur (Salter-Harris type 2) and a metaphyseal fracture of the proximal tibia compatible with floating knee injury Type-C. The patient underwent preoperative investigations, including a neck radiograph, cardiology evaluation, pulmonary assessment, and hematologic check. The patient underwent surgery to fix all fractures.

CLINICAL DISCUSSION

The necessary investigations were carried out to perform anesthesia and measures before, during, and after the operation. Down syndrome may help the patient recover, especially the ROM, due to various musculoskeletal conditions, such as generalized ligamentous laxity, joint hypermobility, and hypotonia.

CONCLUSION

Children with Down syndrome may have various musculoskeletal conditions that can complicate the treatment of other injuries such as floating knee injury. Preoperative investigations should be performed to identify any potential complications.

The Floating Knee in Pediatric Patients: A Single-Center Retrospective Study From a Referral Center

Introduction

An ipsilateral fracture of the femur and tibia (also known as floating knee) is a rare injury in pediatric patients. Recent advances rapidly made the use of intramedullary elastic nails the standard of care in the management of long bone fractures, including floating knee injuries, in patients with immature skeletons. Currently, we have observed a trend of fixing both fractured bones, thus improving functional outcomes, and reducing sequelae. The aim of this study was to report our experience in the management and functional outcomes of floating knee injuries in a single trauma-I level center.

Materials and methods

This is a retrospective study of consecutive cases from June 1, 2018, to March 31, 2022, from a single trauma center. Preoperative and postoperative records and radiographs were assessed, including the epidemiological data and characteristics of the fractures type of treatment, mechanism of injury, complications, and functional evaluation at the last follow-up, which was performed according to the criteria described by Karlstrom and Olerud.

Results

Twenty-five patients were included during the four years of study, of which 18 were male (72%), and the mean age was 9.6 years. Overall, 96% of the cases were related to traffic accidents. An analysis of the provided treatment showed that 19 cases (76%) were resolved with surgery on at least of the bones, and six cases were managed with simultaneous orthopedic treatments in both injuries. Excellent outcomes were achieved in 15 cases (60%), good outcomes in three, fair outcomes in five, and poor outcomes in one. Concerning the classification of injuries according to the criteria developed by Letts and Vincent,it was observed that type D was the most frequent one. With regard to exposed bone injuries, 15 cases presented with open fractures. Complications were found in eight (32%) cases, of which five were related to limb discrepancy and three with functional limitations of the knee, with changes in its range of motion. There was also one case of nonunion of the distal tibia.

Conclusion

Traffic accidents are the main cause of floating knees. Surgical management of the fractures brought satisfactory outcomes and reduced complications. Thus, fixation of injuries is recommended for early return to daily activities and for a reduction in residual complications.