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

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00793637
Recruitment Status : Completed
First Posted : November 19, 2008
Last Update Posted : August 6, 2009
Synthes Inc.
Information provided by:
AO Clinical Investigation and Documentation

Brief Summary:

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.

Condition or disease
Humerus Fracture Femur Fracture Tibia Fracture

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Study Type : Observational
Estimated Enrollment : 30 participants
Observational Model: Case-Only
Time Perspective: Prospective
Official Title: 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
Study Start Date : August 2008
Actual Primary Completion Date : July 2009
Actual Study Completion Date : August 2009

Resource links provided by the National Library of Medicine

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

Primary Outcome Measures :
  1. Surgeon's compliance and handling-oriented questionnaire [ Time Frame: During surgery ]

Secondary Outcome Measures :
  1. Rate of Complications [ Time Frame: 6 months ]
  2. General pain and pain at fracture site assessed by VAS [ Time Frame: 6 months ]
  3. Walking ability in patients with femoral or tibial fractures using the Parker mobility score [ Time Frame: 6 months ]

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

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Ages Eligible for Study:   18 Years and older   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Sampling Method:   Probability Sample
Study Population
orthopedic clinics

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.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT00793637

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Medizinische Universität Innsbruck, Abteilung Unfallchirurgie und Sporttraumatologie
Innsbruck, Austria, 6020
Charité - Universitätsmedizin Berlin, Centrum für Muskuloskeletale Chirurgie
Berlin, Germany, 13353
Universitätsklinikum Mainz, Klinik und Poliklinik für Unfallchirurgie
Mainz, Germany, 55131
BG Unfallklinik Tübingen
Tuebingen, Germany, 72076
Sponsors and Collaborators
AO Clinical Investigation and Documentation
Synthes Inc.
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Principal Investigator: Dankward Hoentzsch, MD BG Unfallklinik Tübingen, 72076 Tübingen, Germany

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Responsible Party: Prof. Dr. med. Dankward Höntzsch, BG Unfallklinik Tübingen, Schnarrenbergstrasse 95 Identifier: NCT00793637    
Other Study ID Numbers: ASLS-Pre-08
First Posted: November 19, 2008    Key Record Dates
Last Update Posted: August 6, 2009
Last Verified: August 2009
Keywords provided by AO Clinical Investigation and Documentation:
Angular stable locking system
Handling test
Additional relevant MeSH terms:
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Fractures, Bone
Femoral Fractures
Humeral Fractures
Tibial Fractures
Wounds and Injuries
Leg Injuries
Arm Injuries