WO2008030201A1

WO2008030201A1 - Manipulation of distraction osteogenesis via drug delivery unit containing distractor

Info

Publication number: WO2008030201A1
Application number: PCT/TR2006/000042
Authority: WO
Inventors: Ersoy Konas; Mehmet Emin Mavili; Halil Ibrahim Canter
Original assignee: Individual
Current assignee: Individual
Priority date: 2006-09-07
Filing date: 2006-09-07
Publication date: 2008-03-13
Anticipated expiration: 2009-03-07
Also published as: TR200904307T2

Abstract

A distractor contains drug delivery unit can release any kind of drugs after surgical intervention while distraction process going on. As the geared rod turns for the distraction, the movement is transmitted to the piston of the delivery unit. The long head of the piston is fixed to the distal mobile part of the distractor and the short head of the piston is inserted in to the posterior orifice of the container which can be designed any kind of geometrical shape or volume. The anterior orifice of the container is located at the distraction zone. It has been demonstrated that continious osteoinductive agent releasing while distraction, facilitates ossification. Any kind of drug can be used to manipulate distraction ostegeogenesis with this device.

Description

MANIPULATION OF DISTRACTION OSTEOGENESIS VIA DRUG DELIVERY UNIT CONTAINING DISTRACTOR

The invention concerns a distractor, used for distraction osteogenesis. The distractor has the capability of drug releasing at the application site while the distraction process going on after surgical intervention.

Distraction osteogenesis involves creation of new bone by the gradual distraction of two bony fragments following their surgical division. The technique is well-established and widely accepted for bone lengthening and defect filling. It has widespread clinical applications in hypoplastic skeleton, cancer surgery, craniofacial anomalies, trauma treatment, traumatic growth disturbances, limb deformities, and nonunion.

Distraction osteogenesis has several advantages over conventional techniques, including less invasive intervention, easier control of infection and minimal donor site morbidity. However, long period of rigid fixation is the most important disadvantage of this technique. Any decrease of the distraction period would improve patient comfort and compliance. Previous attempts to shorten the distraction osteogenesis time, by increasing the rate of distraction have been unsuccessful and associated with high incidence of bony non-union. Control of the infection is another important factor on the success of the distraction osteogenesis. Performance of effective distraction osteogenesis can be enhanced by application of different kind of drugs. These substances have been delivered localized areas or specific bones in the body, thus avoiding systemic toxicity and the need for higher quantities of the desired drug to achieve therapeutic levels at the site of action.

Different types of distraction models and distractors have been developed in last two decades. Continious distraction, two or three dimentional distractions, simultaneous multidirectional distractions, bifocal, trifocal, quadrifocal distractions are among the new developments of distraction osteogenesis. The mechanical technology supplies serious contribution on the technique with spring scale distractors ( Tuncbilek G, Mavili ME, Vargel I₁ Enacar A, Erk Y. Midface distraction using spring scale attached to rigid external device. Plast Reconstr Surg. 2004 Apr 15;113(5):1410-6.) or remote controlable microhydrolik distractor ( Wiltfang J, Kessler P, Merten HA, Neukam FW. Continuous and intermittent bone distraction using a microhydraulic cylindeπan experimental study in minipigs.Br J Oral Maxillofac Surg. 2001 Feb;39(1):2-7. ) on continious distraction.

Besides these developments recent investigations are focused on the bioabsorbable distractors. Although there are many investigations and developments on distraction technologies none of them focused on improving drug delivery system containing distractor. There is only one external distractor described, which has drug injection systems (Grayson BH, Rowe NM, Hollier LH Jr, Williams JK, McCormick S, Longaker MT, McCarthy JG. Development of a device for the delivery of agents to bone during distraction osteogenesis.J Craniofac Surg. 2001 Jan;12(1):19- 25.). Increased infection risks caused by external localization of the distractor and direct contact of bone with atmosphere and necessity of recurrent drug injections are important disadvantages of the distractor. Another important problem with the device is distance of the injection area with the distraction gap. - ~ ^» ' u υ u (J 4 Z

According to the invention these problems solved by means of an internal mounted, drug delivery system containing distractor. With the initiation of the distraction process, osteotomised bony segments becomes separated from each other and certain amount of drug is released in to the distraction gap from the container with the help of a piston.

While the patent invention shall now be described with reference to the preferred embodiments shown in the drawings, it should be understood that the intention is not to limit the invention only to the particular embodiments and medications but rather to cover all alterations, different kind of medications, modifications and equivalent arrangements within the scope of appended claims.

The invention is composed of two major parts, integrated each other called distraction and drug delivery units. The drug delivery unit is consists of injection piston 4 and container 5. The distractor is composed of geared rod 1, outer body 2, main body 3 and fixation plates 6, 7 (Figure 1,2,3). Part list:

1. Geared rod

2. Outer body

3. Main body

4. Piston

5. Container

6. Fixation plate

7. Fixation plate

A geared rod 1 transfers the movement through the main body 3 to the distal segment of the distractor (elongation of the main body 3). This movement causes the separation of proximal and distal parts of the distractor and also bony segments, fixated on the distractor. The long head of the piston 4 of the drug delivery unit is attached to the distal part of the distractor 3 and short head is inserted into the container 5. As the distraction continues, movement of the distal part of the distractor 3 is transferred to the piston 4 and short head of the piston causes the injection of the drug from the container 5 to the distraction gap.

Claims

Claims:

1. An internally mounted distractor for distraction osteogenesis, has capability of drug releasing at the application site while the distraction process going on after surgical intervention by means of the movements of the distractor.

2. A mechanical system which releases any kind of drug with the rotation of the geared rod 1. The movement is transmitted to the piston 4 which is inserted in to the container 5 causes the injection of the drug.

3. A mechanical system as mentioned in claim 2, integrated with the distraction unit, releases drug with the movement of the piston 4 inserted in to the container 5.

4. The piston 4 as mentioned in claim 3 has the same or slightly smaller diameter with the inner diameter of the container 5 which will fit to the posterior orifice of the container 5 (Figure 4). The piston (Figure 1, 2, 3, 4) is designed in same geometrical shape or form with the container 5 for easy sliding in it.

5. The container 5 as claimed in claim 3 has two orifices. The posterior orifice is closed with the piston (Figure 1 , 2, 3, 4) and the anterior one is located at the distraction zone.