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Evaluation of Bisphosphonate Coated Pins for Extern Fixation in Tibia Osteotomy (PFX)

The recruitment status of this study is unknown. The completion date has passed and the status has not been verified in more than two years.
Verified May 2012 by Region Skane.
Recruitment status was:  Active, not recruiting
AddBio AB
Information provided by (Responsible Party):
Region Skane Identifier:
First received: May 23, 2012
Last updated: December 7, 2012
Last verified: May 2012
The purpose of this study is to evaluate the relative osseomechanical strength of a novel coated pin/screw in a clinical model.

Condition Intervention Phase
Device: Biphosfonate
Phase 3

Study Type: Interventional
Study Design: Intervention Model: Single Group Assignment
Masking: Double Blind (Participant, Outcomes Assessor)
Primary Purpose: Treatment
Official Title: Evaluation of Bisphosphonate Coated Pins for Extern Fixation in Tibia Osteotomy

Further study details as provided by Region Skane:

Primary Outcome Measures:
  • To evaluate the relative osseomechanical strength of a novel coated pin/screw in a clinivcal mode. [ Time Frame: 2011-07-01-2012-02-01 ]
    To evaluate the relative osseomechanical strength of a novel coated pin/screw

Estimated Enrollment: 30
Study Start Date: April 2011
Estimated Study Completion Date: February 2013
Primary Completion Date: November 2012 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Pin fixation Device: Biphosfonate
External pins coated by biphosfonate.

Detailed Description:

The pin fixation and the risk for pin loosening and pintract infection is intimately connected Moroni et al., Magyar et al. Toksvig-Larsen and W-Dahl) The pin performance ratio for insertion to extraction torque (PPI) varies significantly between screw types.

The extraction torque force is the most important value and it is estimated that a removal torque around 300 Nm probably will be the best bon-pin fixation in clinical practice.

In animal studies and even in clinical studies the hydroxyapatite (HA) coated screw retained the highest level of osseointegration. However, the fixation for HAscrews is, especially in diaphyseal bone, the risk for too tight fixation, with extreme difficulties to remove the screws in few cases as a result ( high pain and seldom it is impossible to remove the screw) Coating by biphosphonate is a new novel technique with preclinical appealing performance, which theoretically should make this coating very appealing in clinical practice. The theory behind this technique is that it create a good pinfixation reasonable easy to remove.

The current most used cortical screw designs performed poorest in terms of fixation (PPI)


Using the hemicallotasis technique for correction in high tibial osteotomies today, HA coated (Osteotite) conical 130/50 screws is used in the proximal tibia - the metaphysic - and plain (standard) cortical conical screws 110/40 is used in the diaphysis.

To study the effect of an improved pin coating a study including 30 patients randomised to the standard procedure today or the novel technique using biphosphonate coated screws.

In the metaphysic, the randomisation will be between the HA coated (Osteotite) screws and the biphosphonated coated screws 130/50 (screw thread 50mm) In the diaphysis the randomisation will be between the plain standard 110/40 screws and the biphosphonate 110/40 coated screws

Totally 30 patients will be studied which means totally 120 pins. This has been based on power calculations resulting in 23 patients in each group and calculated on extraction torque force. This is a clinical study and 30 patients is estimated due to expected drop out.


Ages Eligible for Study:   20 Years to 80 Years   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • All patients which are diagnostiserade med arthr and needs an operation.
  Contacts and Locations
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Please refer to this study by its identifier: NCT01745276

Orthopeadic Clinic Hospital
Hassleholm, Sweden, 28125
Sponsors and Collaborators
Region Skane
AddBio AB
  More Information

Responsible Party: Region Skane Identifier: NCT01745276     History of Changes
Other Study ID Numbers: PFX-2009378
Study First Received: May 23, 2012
Last Updated: December 7, 2012

Keywords provided by Region Skane:
Pin fixation

Additional relevant MeSH terms:
Joint Diseases
Musculoskeletal Diseases
Rheumatic Diseases
Bone Density Conservation Agents
Physiological Effects of Drugs processed this record on May 25, 2017