Dynamic Locking Screws 5.0 vs. Standard Locking Screws in Fracture of Distal Femur Treated With Locked Plate Fixation

Phase 4

Terminated

Interventions: Device: DLS 5.0 (Dynamic locking screws)
Device: SLS (Standard locking screw)

Brief Summary: The purpose of this study is to evaluate the performance of Dynamic Locking Screws (DLS) used to stabilize the shaft component of distal femur fractures in comparison to standard locking screws (SLS). The hypothesis is that DLS will lead to better functional outcomes (WOMAC score) due to increased and more symmetrical callus formation and fewer non-unions.

Recruitment & Eligibility

Inclusion Criteria

21 years and older
Closed or open distal femur fracture (AO 33 A1-3, 33 C1-3) including distal femur fractures above a total knee arthroplasty
Ability to walk independently prior to injury
Eligible for treatment with ORIF of the distal femur with a large fragment locking plate (LISS, LCP)
Willing and able to comply with post-operative protocol and return for follow-up.
Ability to understand the content of the patient information / informed consent form and participate in the clinical investigation
Signed informed consent

Exclusion Criteria

Additional ipsi- or contralateral lower extremity fracture
Any kind of implant at the ipsilateral proximal femur
Pre-existing malunion or nonunion of the ipsilateral lower extremity
Segmental bone defect requiring bone grafting
More than 4 weeks between injury and surgery
Pathologic fracture due to a disease other than osteoporosis (eg, tumor, metastasis)
Polytrauma
Active malignancy
Any not medically managed severe systemic disease
Recent history of substance abuse (ie, recreational drugs, alcohol) that would preclude reliable assessment
Pregnancy or women planning to conceive within the study period
Prisoner
Participation in any other medical device or medicinal product study within the previous month that could influence the results of the present study

Arm && Interventions

Group	Intervention	Description
DLS 5.0 (Dynamic Locking Screws)	DLS 5.0 (Dynamic locking screws)	ORIF with DLS 5.0 (Dynamic Locking Screws)
SLS (Standard locking screw)	SLS (Standard locking screw)	ORIF with SLS (Standard locking screw)

Primary Outcome Measures

Name	Time	Method
Western Ontario and McMaster Universities Index (WOMAC)	12 months after surgery	To assess pain, stiffness, and physical function

Secondary Outcome Measures

Name	Time	Method
Quality of Life (EuroQol-5D)	Preoperative, 6 weeks ±7 days, 12 weeks ± 7 days, 6 months ± 30 days, 12 months up to 425 days after surgery
Range of Motion (ROM)	6 weeks ±7 days, 12 weeks ± 7 days, 6 months ± 30 days, 12 months up to 425 days after surgery	Assessment of passive ROM of the knee (flexion - extension)
Timed Up-and-go Test (TUG)	12 weeks ± 7 days, 6 months ± 30 days	The TUG measures the time (in seconds) that it takes for an individual to rise from an armchair (chair seat height = 45 cm / 1.5 feet), walk 3 meters (= 10 feet) to a line drawn on the floor, turn around and return to the chair. The time is measured from a seated position (back against the backrest) with a stopwatch started on the command "ready - go" and stopped when the seated position is reached again.
Full Weight-bearing Status	weekly measurement at home	Assessment of the timepoint when the patient : * can bear the whole body weight on the affected leg at single-leg-stance for 3 seconds * can walk without walking aid * has no intake of analgesics * has a pain level experienced at the fracture site during weight bearing over two consecutive measurements with a value of ≤ 3 as measured on a 0-10 numeric rating scale (NRS), where 0 = no pain and 10 = worst pain imaginable
WOMAC	Preoperative, 6 weeks ±7 days, 12 weeks ± 7 days, 6 months ± 30 days, 12 months up to 425 days after surgery	To assess pain, stiffness, and physical function

Locations (12): University of Missouri Orthopaedics
🇺🇸
Columbia, Missouri, United States
Washington University Orthopedics
🇺🇸
Saint Louis, Missouri, United States
Wilhelminenspital
🇦🇹
Wien, Austria
Harborview Medical Center
🇺🇸
Seattle, Washington, United States
BGU Tübingen
🇩🇪
Tübingen, Germany
Cantonal Hospital Chur
🇨🇭
Chur, Switzerland
Universitätsklinikum des Saarlandes
🇩🇪
Homburg, Germany
Hospital of the University of Pennsylvania
🇺🇸
Philadelphia, Pennsylvania, United States
Charité Berlin, Campus Virchow Klinikum
🇩🇪
Berlin, Germany
UC Davis Medical Center
🇺🇸
Sacramento, California, United States
Luzerner Kantonsspital
🇨🇭
Luzern, Switzerland
Universitätsspital Zürich
🇨🇭
Zürich, Switzerland