Dynamization module for external fixation strut

An adjustment sleeve that may be slidably disposed within an axial bore of a strut housing, the adjustment sleeve comprising:

• a first and a second bores extending from a top surface to a bottom surface of the adjustment sleeve;
• a first sleeve member having a proximal end, a distal end, and at least a partial axial bore extending from the distal end towards the proximal end;
• a second sleeve member adjoining the first sleeve member, wherein the second sleeve member comprises a body having an annular surface that is substantially proximal to the distal end of the first sleeve member, and a beveled end that is slidably disposed within the axial bore of the first sleeve member;
• a biasing mechanism between the first sleeve member and the second sleeve member positioned between the first sleeve member and the second sleeve member;
• and
• an adjustment mechanism that comprises an element that passes through the second bore and comes in contact with the beveled end of the second sleeve member, wherein adjusting the element changes a vertical position of the element in relation to the adjustment sleeve and is thereby operable to control a longitudinal displacement of the beveled end that is slidably disposed within the axial bore of the first sleeve member and is in contact with the element.

A method of assembling a strut having a longitudinal axis defined therethrough, the method comprising:

• providing a strut housing having a housing adjustment aperture and at least a partial axial bore defined therethrough;
• providing an adjustment sleeve slidably disposed within the axial bore of the strut housing, wherein the adjustment sleeve comprises
• a first and a second bores extending from a top surface towards a bottom surface of the adjustment sleeve,
• a first sleeve member having a proximal end, a distal end, and at least a partial axial bore extending from the distal end towards the proximal end,
• a second sleeve member adjoining the first sleeve member, wherein the second sleeve member comprises a body having an annular surface that is substantially proximal to the distal end of the first sleeve member, the second sleeve member having a beveled end that is slidably disposed within the axial bore of the first sleeve member, and
• a biasing mechanism positioned between the first sleeve member and the second sleeve member;
• releasably coupling the strut housing with the adjustment sleeve with a fastener, wherein the fastener extends from the housing adjustment aperture to the first bore;
• and controlling, with an adjustment member, a longitudinal placement of the beveled end that is slidably disposed within the axial bore of the first sleeve member, wherein the adjustment mechanism comprises an element that passes through the second bore and comes in contact with the beveled end of the second sleeve member, wherein adjusting the element changes a vertical position of the element in relation to the adjustment sleeve.

A method of adjusting the position of two bone segments, the method comprising:

• identifying a patient in need of having the position of the two bone segments adjusted;
• affixing an external fixation frame to the two bone segments, wherein the external fixation frame comprises two or more fixation plates or rings;
• connecting the two or more fixation plates or rings of the external fixation frame with one or more struts that provide for bone dynamization, each of the one or more struts having a longitudinal axis defined therein and comprising:
• a strut housing having a housing adjustment aperture and at least a partial axial bore defined therethrough;
• an adjustment sleeve slidably disposed within the axial bore of the strut housing, the adjustment sleeve comprising:
• first and second bores extending from a top surface towards a bottom surface of the adjustment sleeve;
• a first sleeve member having a proximal end, a distal end, and at least a partial axial bore extending from the distal end towards the proximal end;
• a second sleeve member adjoining the first sleeve member, wherein the second sleeve member comprises a body having an annular surface that is substantially proximal to the distal end of the first sleeve member, the second sleeve member having a beveled end that is slidably disposed within the axial bore of the first sleeve member;
• and
• a biasing mechanism positioned between the first sleeve member and the second sleeve member;
• a fastener that releasably couples the strut housing to the adjustment sleeve, wherein the fastener extends from the housing adjustment aperture to the first bore;
• and
• an adjustment mechanism that comprises an element that passes through the second bore and comes in contact with the beveled end of the second sleeve member, wherein adjusting the element changes a vertical position of the element in relation to the adjustment sleeve and is thereby operable to control a longitudinal displacement of the beveled end that is in contact with the element and is slidably disposed within the axial bore of the first sleeve member;
• and
• adjusting an amount of dynamization of the strut to maximize a strength of bone growth between the two bone segments during bone remodeling.