Evaluation of Handling and Possible Complications Related to the Newly Developed Angular Stable Locking System (ASLS) (ASLS-Pre)

Prospective Multicenter Case Series to Evaluate Handling and Possible Complications Related to the Angular Stable Locking System in Patients With Proximal and Distal Tibial, Femoral and Humeral Fractures Treated With Intramedullary Nails

In many cases, the existing locking bolts and screws in intramedullary nails do not provide sufficient stability. Due to the play between screw and nail, the reduction can be lost and the instability can result in malunions, nonunions, or pseudoarthrosis. Consequently, secondary angular fracture dislocation (defined as a difference of the angle of 10° or more from the post-operative to the follow-up x-rays) can be observed in approximately 30% of patients after conventional intramedullary nailing of proximal third tibial fractures and in approximately 0-2% in patients with distal third tibial fractures. Therefore, an Angular Stable Locking System for Intramedullary Nails (ASLS) was developed to reduce the risk of secondary loss of reduction by providing axial and angular stability. ASLS provides angular stable fixation between nails and screws with resorbable sleeves used as dowels in the nail locking holes.

The present study evaluates the handling of ASLS and the surgeon's compliance as well as any complications occurring during the baseline and the follow-up period in patients with proximal and distal tibial, femoral and humeral fractures treated with intramedullary nails. Furthermore, the relationship of any occurred complications to ASLS will be assessed.

Study Overview

• Status: Completed
• Conditions: Humerus Fracture; Femur Fracture; Tibia Fracture

• Study Type: Observational
• Enrollment (Anticipated): 30

Contacts and Locations

Study Locations

• Austria
  • Innsbruck, Austria, 6020
    • Medizinische Universität Innsbruck, Abteilung Unfallchirurgie und Sporttraumatologie
• Germany
  • Berlin, Germany, 13353
    • Charité - Universitätsmedizin Berlin, Centrum für Muskuloskeletale Chirurgie
  • Mainz, Germany, 55131
    • Universitätsklinikum Mainz, Klinik und Poliklinik für Unfallchirurgie
  • Tuebingen, Germany, 72076
    • BG Unfallklinik Tübingen

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Probability Sample

Study Population

orthopedic clinics

Description

Inclusion Criteria:

• The patient is ≥ 18 years old
• One of the following bones is fractured so that the fracture is affecting the proximal or the distal third of the bone without affecting the joint surface: Humerus, Femur, Tibia
• The fracture is fixed with one of the following cannulated implants Humerus: Expert HN, Expert PHN. Femur: Expert LFN, Expert RAFN, CFN, DFN, AFN. Tibia: Expert TN, CTN.
• The patient is willing and able to participate in the study follow-up according to the CIP.
• The patient is able to understand and read local language at elementary level.
• The patient is willing and able to give written informed consent to participate in the study.

Exclusion criteria:

• The patient is legally incompetent.
• Preexistent malunion or nonunion of the bone that is planned to be treated with ASLS.
• The patient suffers from a polytrauma (multiple injuries, whereof one or the combination of several injuries is life-threatening).
• The patient suffers from active malignancy.
• The patient is affected by drug or alcohol abuse.
• The patient has participated in any other device or drug related clinical trial within the previous month.

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort
Surgical; Patients with proximal and/or distal tibial, femoral and/or humeral fractures treated with intramedullary nails and the Angular Stable Locking System(ASLS)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Surgeon's compliance and handling-oriented questionnaire	During surgery

Secondary Outcome Measures

Outcome Measure	Time Frame
Rate of Complications	6 months
General pain and pain at fracture site assessed by VAS	6 months
Walking ability in patients with femoral or tibial fractures using the Parker mobility score	6 months

Collaborators and Investigators

• Sponsor: AO Clinical Investigation and Publishing Documentation
• Collaborators: Synthes Inc.
• Investigators: Principal Investigator: Dankward Hoentzsch, MD, BG Unfallklinik Tübingen, 72076 Tübingen, Germany

Study record dates

Study Major Dates

• Study Start: August 1, 2008
• Primary Completion (ACTUAL): July 1, 2009
• Study Completion (ACTUAL): August 1, 2009

Study Registration Dates

• First Submitted: November 17, 2008
• First Submitted That Met QC Criteria: November 17, 2008
• First Posted (ESTIMATE): November 19, 2008

Study Record Updates

• Last Update Posted (ACTUAL): July 22, 2021
• Last Update Submitted That Met QC Criteria: July 21, 2021
• Last Verified: August 1, 2009

More Information

Terms related to this study

• Keywords: Complications; Angular stable locking system; Handling test
• Additional Relevant MeSH Terms: Wounds and Injuries; Leg Injuries; Arm Injuries; Femoral Fractures; Fractures, Bone; Tibial Fractures; Humeral Fractures
• Other Study ID Numbers: ASLS-Pre-08