Ergonomic knob insert for hollow stick

Abstract

Described is a knob insert for application to the gripping end of a hockey stick. The knob insert comprises a rounded, oblique, cylindrical support structure, transitional shaft and tang aligned on a common longitudinal central axis. The support structure comprises a greater diameter rounded, cantle-like support and gripping structures.

What is claimed is: 
     
         1 . A knob insert for insertion into the hollow shaft of a hockey stick, the knob insert comprising a tang for insertion into the hollow shaft of the hockey stick, a knob adapted to be grasped by the hand of an athlete when the tang is inserted into the hollow shaft of the hockey stick, and a step between the tang and the knob adapted to abut an end surface of the hollow shaft of the hockey stick when the tang is inserted therein, the tang, step and knob being aligned along a central longitudinal axis extending from a tang end to a knob end of the knob insert, wherein
 the knob comprises an anterior cantle region and a corresponding posterior cantle region, the anterior and posterior cantle regions being between the step and the knob end and on opposing sides of an imaginary coronal plane containing the central longitudinal axis and divided by an imaginary sagittal plane that contains the central longitudinal axis and is orthogonal to the imaginary coronal plane; the anterior and posterior cantle regions each providing a curved support surface for the hand of the athlete when the athlete is gripping the hockey stick, the anterior cantle region and the posterior cantle region each having a radius of curvature in the sagittal plane, the radius of curvature of the anterior cantle region being less than the radius of curvature of the posterior cantle region,   the tang and the knob comprise a shaft that extends from a position proximate the tang end to a position proximate the knob end of the knob insert,   the knob further comprises a sheath that is coupled to and surrounds the shaft, and   the shaft and the sheath are discrete components having different properties.   
     
     
         2 . A knob insert adapted for insertion into the hollow shaft of a hockey stick, the knob insert comprising a central longitudinal axis, a tang for insertion into the hollow shaft of the hockey stick, a knob adapted to be grasped by the hand of an athlete when the tang is inserted into the hollow shaft of the hockey stick, a step between the tang and the knob, a tang end, and a knob, the tang and knob ends being opposing ends of the knob insert and aligned the central longitudinal axis, the knob comprising a flange proximate the knob end, an anterior cantle region, and a posterior cantle region, wherein
 (i) the anterior and posterior cantle regions are between the step and the flange,   (ii) the anterior and posterior cantle regions, in combination, provide a curved support surface for the hand of the athlete,   (iii) each of the anterior and posterior cantle regions are bisected into symmetrical halves by an imaginary sagittal plane that contains the central longitudinal axis, and   (iv) the anterior and posterior cantle regions are on opposing sides of and asymmetric relative to each other about an imaginary coronal plane that contains the central longitudinal axis and is orthogonal to the sagittal plane.   
     
     
         3 . The knob insert of any preceding claim wherein the longitudinal axis is substantially linear. 
     
     
         4 . The knob insert of any preceding claims wherein a ratio of the radius of curvature of the posterior cantle region to the radius of curvature of the anterior cantle region is at least 1:2, respectively. 
     
     
         5 . The knob insert of any preceding claims wherein a ratio of the radius of curvature of the posterior cantle region to the radius of curvature of the anterior cantle region is at least 1:3, respectively. 
     
     
         6 . The knob insert of any preceding claims wherein a ratio of the radius of curvature of the posterior cantle region to the radius of curvature of the anterior cantle region is at least 1:5, respectively. 
     
     
         7 . The knob insert of any preceding claims wherein a ratio of the radius of curvature of the posterior cantle region to the radius of curvature of the anterior cantle region is less than 1:20. 
     
     
         8 . The knob insert of any preceding claims wherein a ratio of the radius of curvature of the posterior cantle region to the radius of curvature of the anterior cantle region is less than 1:15, respectively. 
     
     
         9 . The knob insert of any preceding claims wherein a ratio of the radius of curvature of the posterior cantle region to the radius of curvature of the anterior cantle region is less than 1:10, respectively. 
     
     
         10 . The knob insert of any preceding claims wherein the knob has an outer diameter that varies as a function of position along the central longitudinal axis with the minimum outer diameter occurring at a position along the longitudinal axis that is greater than 50% of the distance between the knob end and the step, as measured from the step. 
     
     
         11 . The knob insert of any preceding claims wherein the knob has an outer diameter that varies as a function of position along the central longitudinal axis with the minimum outer diameter occurring at a position along the longitudinal axis that is greater than 55% of the distance between the knob end and the step, as measured from the step. 
     
     
         12 . The knob insert of any preceding claims wherein the knob has an outer diameter that varies as a function of position along the central longitudinal axis with the minimum outer diameter occurring at a position along the longitudinal axis that is greater than 60% of the distance between the knob end and the step, as measured from the step. 
     
     
         13 . The knob insert of any preceding claims wherein the knob has an outer diameter that varies as a function of position along the central longitudinal axis with the minimum outer diameter occurring at a position along the longitudinal axis that is greater than 65% of the distance between the knob end and the step, as measured from the step. 
     
     
         14 . The knob insert of any of  claims 10  to  13  wherein the minimum diameter of the knob is about 65% to 95% of the diameter of the knob at the step. 
     
     
         15 . The knob insert of any of  claims 10  to  13  wherein the minimum diameter of the knob is about 65% to 90% of the diameter of the knob at the step. 
     
     
         16 . The knob insert of any of  claims 10  to  13  wherein the minimum diameter of the knob is about 70% to 90% of the diameter of the knob at the step. 
     
     
         17 . The knob insert of any of  claims 10  to  13  wherein the minimum diameter of the knob is about 65% to 85% of the diameter of the knob at the step. 
     
     
         18 . The knob insert of any of  claims 10  to  13  wherein the minimum diameter of the knob is about 70% to 85% of the diameter of the knob at the step. 
     
     
         19 . The knob insert of any of  claims 10  to  13  wherein the minimum diameter of the knob is about 75% to 85% of the diameter of the knob at the step. 
     
     
         20 . The knob insert of any preceding claims wherein the imaginary sagittal plane bisects the knob into symmetrical halves. 
     
     
         21 . The knob insert of any preceding claims wherein the knob insert has a length, as measured from the tang end to the knob end and along the central longitudinal axis of 4.5 to 8 inches. 
     
     
         22 . The knob insert of any preceding claims wherein the knob insert has a length, as measured from the tang end to the knob end and along the central longitudinal axis of 4.5 to 7.5 inches. 
     
     
         23 . The knob insert of any preceding claims wherein the knob insert has a length, as measured from the tang end to the knob end and along the central longitudinal axis of 4.5 to 7 inches. 
     
     
         24 . The knob insert of any preceding claims wherein the knob insert has a length, as measured from the tang end to the knob end and along the central longitudinal axis of 4.5 to 6.5 inches. 
     
     
         25 . The knob insert of any preceding claims wherein the knob insert has a length, as measured from the tang end to the knob end and along the central longitudinal axis of 5 to 8 inches. 
     
     
         26 . The knob insert of any preceding claims wherein the knob insert has a length, as measured from the tang end to the knob end and along the central longitudinal axis of 5 to 7.5 inches. 
     
     
         27 . The knob insert of any preceding claims wherein the knob insert has a length, as measured from the tang end to the knob end and along the central longitudinal axis of 5 to 7 inches. 
     
     
         28 . The knob insert of any preceding claims wherein the knob insert has a length, as measured from the tang end to the knob end and along the central longitudinal axis of 5 to 6.5 inches. 
     
     
         29 . The knob insert of any preceding claims wherein the knob insert has a length, as measured from the tang end to the knob end and along the central longitudinal axis of 5.5 to 8 inches. 
     
     
         30 . The knob insert of any preceding claims wherein the knob insert has a length, as measured from the tang end to the knob end and along the central longitudinal axis of 5.5 to 7.5 inches. 
     
     
         31 . The knob insert of any preceding claims wherein the knob insert has a length, as measured from the tang end to the knob end and along the central longitudinal axis of 5.5 to 7 inches. 
     
     
         32 . The knob insert of any preceding claims wherein the knob insert has a length, as measured from the tang end to the knob end and along the central longitudinal axis of 5.5 to 6.5 inches. 
     
     
         33 . The knob insert of any preceding claims wherein the knob insert has a length, as measured from the tang end to the knob end and along the central longitudinal axis of 6 to 8 inches. 
     
     
         34 . The knob insert of any preceding claims wherein the knob insert has a length, as measured from the tang end to the knob end and along the central longitudinal axis of 6 to 7.5 inches. 
     
     
         35 . The knob insert of any preceding claims wherein the knob insert has a length, as measured from the tang end to the knob end and along the central longitudinal axis of 6 to 7 inches. 
     
     
         36 . The knob insert of any preceding claims wherein the knob insert has a length, as measured from the tang end to the knob end and along the central longitudinal axis of 6 to 6.5 inches. 
     
     
         37 . The knob insert of any preceding claims wherein the sheath comprises a polymer. 
     
     
         38 . The knob insert of any preceding claims wherein the sheath comprises an injection molded polymer. 
     
     
         39 . The knob insert of any preceding claims wherein the sheath comprises an injection molded thermoplastic polymer. 
     
     
         40 . The knob insert of any preceding claims wherein the sheath comprises a thermoplastic vulcanizate. 
     
     
         41 . The knob insert of any preceding claims wherein the sheath comprises a polymeric material having a durometer hardness of 75 Shore A, 5 sec, injection molded. 
     
     
         42 . The knob insert of any preceding claims wherein the insert shaft and the sheath comprise materials having a chemically distinct composition. 
     
     
         43 . The knob insert of any preceding claims wherein the insert shaft comprises a polymeric material. 
     
     
         44 . The knob insert of any preceding claims wherein the insert shaft comprises a thermoplastic polymeric material. 
     
     
         45 . The knob insert of any preceding claims wherein the insert shaft comprises a composite of a thermoplastic polymeric and a fiber reinforcing material. 
     
     
         46 . The knob insert of any preceding claims wherein the insert shaft comprises a composite of a thermoplastic polymer and a glass fiber reinforcing material. 
     
     
         47 . The knob insert of any preceding claims wherein the insert shaft has a flexural strength of at least 10,000 psi as determined in accordance with ASTM D790. 
     
     
         48 . The knob insert of any preceding claims wherein the insert shaft has a flexural strength of at least 15,000 psi as determined in accordance with ASTM D790. 
     
     
         49 . The knob insert of any preceding claims wherein the insert shaft has a flexural strength of at least 20,000 psi as determined in accordance with ASTM D790. 
     
     
         50 . The knob insert of any preceding claims wherein the insert shaft has a flexural strength of at least 25,000 psi as determined in accordance with ASTM D790. 
     
     
         51 . The knob insert of any preceding claims wherein the insert shaft has a flexural strength of at least 30,000 psi as determined in accordance with ASTM D790. 
     
     
         52 . The knob insert of any preceding claims wherein the insert shaft has a flexural strength of at least 35,000 psi as determined in accordance with ASTM D790. 
     
     
         53 . The knob insert of any preceding claims wherein the insert shaft has a flexural strength of at least 40,000 psi as determined in accordance with ASTM D790. 
     
     
         54 . The knob insert of any preceding claims wherein the knob insert has a mass of 80 to 115 grams. 
     
     
         55 . The knob insert of any preceding claims wherein the knob insert has a mass of 40 to 75 grams. 
     
     
         56 . The knob insert of any preceding claims wherein the knob insert has a mass of 100 to 150 grams. 
     
     
         57 . The knob insert of any preceding claims wherein the posterior cantle region smoothly transitions about the central longitudinal axis to the anterior cantle region. 
     
     
         58 . The knob insert of any preceding claims wherein the knob end has a circumference that is at least 110% of the circumference of the neck. 
     
     
         59 . The knob insert of any preceding claims wherein the knob end has a circumference that is at least 150% of the circumference of the neck. 
     
     
         60 . The knob insert of any preceding claims wherein the knob end has a circumference that is at least 200% of the circumference of the neck. 
     
     
         61 . The knob insert of any preceding claims wherein the knob end has a circumference that is at least 300% of the circumference of the neck. 
     
     
         62 . The knob insert of any preceding claims wherein the tang has a length measured along the central longitudinal axis of about 2 to about 12 inches. 
     
     
         63 . The knob insert of any preceding claims wherein the tang has an end that is chamfered at an angle of about 30° to 60° from the longitudinal sides of the tang and toward the longitudinal central axis to allow for easier initial guided insertion of the tang into the hollow end of the stick. 
     
     
         64 . The knob insert of any preceding claims wherein the tang has grooves, which run parallel to the central longitudinal axis of the tang. 
     
     
         65 . The knob insert of any preceding claims wherein the tang has chamfered corners which are parallel to the central longitudinal axis of the knob. 
     
     
         66 . The knob insert of any preceding claims wherein the knob has a length, as measured along central longitudinal axis  1 . 1 , that is about 5 to about 95% of the length of the knob and the tang has a complementary length, as measured along the central longitudinal axis, that is about 95 to about 5% of the length of the knob. 
     
     
         67 . The knob insert of any preceding claims wherein the knob has a length, as measured along central longitudinal axis that is about 15 to about 85% of the length of the knob insert and the tang has a complementary length, as measured along the central longitudinal axis, that is about 85 to about 15% of the length of the knob insert. 
     
     
         68 . The knob insert of any preceding claims wherein the knob has a length, as measured along central longitudinal axis that is about 25 to about 75% of the length of the knob insert and the tang has a complementary length, as measured along the central longitudinal axis, that is about 75 to about 25% of the length of the knob insert. 
     
     
         69 . The knob insert of any preceding claims wherein the knob has a length, as measured along central longitudinal axis that is about 35 to about 65% of the length of the knob insert and the tang has a complementary length, as measured along the central longitudinal axis, that is about 65 to about 35% of the length of the knob insert. 
     
     
         70 . The knob insert of any preceding claims wherein the knob has a length, as measured along central longitudinal axis that is about 40 to about 60% of the length of the knob insert and the tang has a complementary length, as measured along the central longitudinal axis, that is about 60 to about 40% of the length of the knob insert. 
     
     
         71 . The knob insert of any preceding claims wherein the knob comprises a neck between the flange and the tang. 
     
     
         72 . The knob insert of any preceding claims wherein the neck has a length measured along the central longitudinal axis of at least about 0.25 inches. 
     
     
         73 . The knob insert of any preceding claims wherein the neck has a length measured along the central longitudinal axis in the range of about 0.25 to about 4 inches. 
     
     
         74 . The knob insert of any preceding claims wherein the neck has a length measured along the central longitudinal axis in the range of about 1 to about 4 inches. 
     
     
         75 . The knob insert of any preceding claims wherein the neck has a length measured along the central longitudinal axis in the range of about 1 to about 2 inches. 
     
     
         76 . The knob insert of any preceding claims wherein the shaft comprises a ceramic, metal, polymer, composite, wood or a composite or laminate thereof. 
     
     
         77 . The knob insert of any preceding claim wherein the shaft comprises a ceramic, metal, polymer, composite, or a composite or laminate thereof. 
     
     
         78 . The knob insert of any preceding claim wherein the shaft has an overall shape that generally corresponds to the overall shape of the knob. 
     
     
         79 . The knob insert of any preceding claim wherein the shaft is bisected by the sagittal plane into symmetric halves. 
     
     
         80 . The knob insert of any preceding claim wherein the shaft comprises an anterior cantle region a posterior cantle region. 
     
     
         81 . The knob insert of any preceding claim wherein the shaft comprises an anterior cantle region and a posterior cantle region, each of which gradually curves away from central longitudinal axis with shaft anterior cantle region having a radius of curvature R CASP2  in the sagittal plane that is less than the radius of curvature R CPSP2  of shaft posterior cantle region in the sagittal plane. 
     
     
         82 . The knob insert of any preceding claim wherein the shaft comprises an anterior cantle region and a posterior cantle region, each of which gradually curves away from central longitudinal axis with shaft anterior cantle region having a radius of curvature R CASP2  in the sagittal plane that is less than the radius of curvature R CPSP2  of shaft posterior cantle region in the sagittal plane and the ratio of R Pc  to R Ac  is at least 2:1. 
     
     
         83 . The knob insert of any preceding claim wherein the shaft comprises an anterior cantle region and a posterior cantle region, each of which gradually curves away from central longitudinal axis with shaft anterior cantle region having a radius of curvature R CASP2  in the sagittal plane that is less than the radius of curvature R CPSP2  of shaft posterior cantle region in the sagittal plane and the ratio of R CPSP2  to R CASP2  is at least 3:1. 
     
     
         84 . The knob insert of any preceding claim wherein the shaft comprises an anterior cantle region and a posterior cantle region, each of which gradually curves away from central longitudinal axis with shaft anterior cantle region having a radius of curvature R CASP2  in the sagittal plane that is less than the radius of curvature R CPSP2  of shaft posterior cantle region in the sagittal plane and the ratio of R CPSP2  to R CASP2  is at least 4:1. 
     
     
         85 . The knob insert of any preceding claim wherein the shaft comprises an anterior cantle region and a posterior cantle region, each of which gradually curves away from central longitudinal axis with shaft anterior cantle region having a radius of curvature R CASP2  in the sagittal plane that is less than the radius of curvature R CPSP2  of shaft posterior cantle region in the sagittal plane and the ratio of R CPSP2  to R CASP2  is at least 5:1. 
     
     
         86 . The knob insert of any preceding claim wherein the shaft comprises an anterior cantle region and a posterior cantle region, each of which gradually curves away from central longitudinal axis with shaft anterior cantle region having a radius of curvature R CASP2  in the sagittal plane that is less than the radius of curvature R CPSP2  of shaft posterior cantle region in the sagittal plane and the ratio of R CPSP2  to R CASP2  is at least about 20:1. 
     
     
         87 . The knob insert of any preceding claim wherein the shaft comprises an anterior cantle region and a posterior cantle region, each of which gradually curves away from central longitudinal axis with shaft anterior cantle region having a radius of curvature R CASP2  in the sagittal plane that is less than the radius of curvature R CPSP2  of shaft posterior cantle region in the sagittal plane and the ratio of R CPSP2  to R CASP2  is in the range of about 4:1 to about 17.5:1. 
     
     
         88 . The knob insert of any preceding claim wherein the shaft comprises an anterior cantle region and a posterior cantle region, each of which gradually curves away from central longitudinal axis with shaft anterior cantle region having a radius of curvature R CASP2  in the sagittal plane that is less than the radius of curvature R CPSP2  of shaft posterior cantle region in the sagittal plane and the ratio of R CPSP2  to R CASP2  is in the range of about 5:1 to about 10:1. 
     
     
         89 . The knob insert of any preceding claim wherein the shaft comprises an anterior cantle region and a posterior cantle region, each of which gradually curves away from central longitudinal axis with shaft anterior cantle region having a radius of curvature R CC1  in the coronal plane that is of comparable magnitude to the radius of curvature R CC2  of shaft posterior cantle region in the coronal plane. 
     
     
         90 . A combination of a hockey stick and a knob insert, the knob insert corresponding to the knob insert of any of the preceding claims and being inserted into a hollow end of the hockey stick. 
     
     
         91 . A combination of a hockey stick and a knob insert, the knob insert corresponding to the knob insert of any of the preceding claims, the knob insert being inserted into a hollow end of the hockey stick wherein the anterior cantle region of knob is on the same side of the hockey stick as the blade of the hockey stick. 
     
     
         92 . The combination of any of the preceding claims wherein the knob comprises a cavity at the knob end sized to accommodate a motion sensor. 
     
     
         93 . The combination of any of the preceding claims wherein the knob comprises a cavity at grip end of the knob sized to accommodate a motion sensor, and the combination further comprises an electronic motion sensor housed in the cavity. 
     
     
         94 . The combination of any preceding claim wherein the sheath has an outer surface having a coefficient of friction that is at least 50% of the coefficient of friction of the outer surface of the hockey stick adjacent the knob insert. 
     
     
         95 . The combination of any preceding claim wherein the sheath has an outer surface having a coefficient of friction that is at least 60% of the coefficient of friction of the outer surface of the hockey stick adjacent the knob insert. 
     
     
         96 . The combination of any preceding claim wherein the sheath has an outer surface having a coefficient of friction that is at least 70% of the coefficient of friction of the outer surface of the hockey stick adjacent the knob insert. 
     
     
         97 . The combination of any preceding claim wherein the sheath has an outer surface having a coefficient of friction that is at least 80% of the coefficient of friction of the outer surface of the hockey stick adjacent the knob insert. 
     
     
         98 . The combination of any preceding claim wherein the sheath has an outer surface having a coefficient of friction that is at least 90% of the coefficient of friction of the outer surface of the hockey stick adjacent the knob insert. 
     
     
         99 . The combination of any preceding claim wherein the sheath has an outer surface having a coefficient of friction that is at least 100% of the coefficient of friction of the outer surface of the hockey stick adjacent the knob insert. 
     
     
         100 . The combination of any preceding claim wherein the sheath has an outer surface having a coefficient of friction that is at least 110% of the coefficient of friction of the outer surface of the hockey stick adjacent the knob insert. 
     
     
         101 . The combination of any preceding claim wherein the sheath has an outer surface having a coefficient of friction that is at least 120% of the coefficient of friction of the outer surface of the hockey stick adjacent the knob insert. 
     
     
         102 . A knob insert of any preceding claim inserted into a hollow end of the hockey stick wherein the anterior cantle region of knob insert, when engaged with the hypothenar of the gripping hand provides increased leverage on the hockey stick. 
     
     
         103 . A knob insert of any preceding claim inserted into a hollow end of the hockey stick wherein the anterior cantle region of the knob insert, when engaged with the hypothenar of the gripping hand, increases the surface area of contact between the hand and the hockey stick. 
     
     
         104 . A knob insert of any preceding claim inserted into a hollow end of the hockey stick wherein the anterior cantle region of knob, when engaged with the hypothenar of the gripping hand provides increased surface area between the knob insert and the hand thus distributing pressure from a smaller focused area to a larger less-focused distribution of pressure to the gripping hand. 
     
     
         105 . A knob insert of any preceding claim inserted into a hollow end of the hockey stick wherein the knob sheath, when gripped by the hand provides improved contact with the palmer arches of the gripping hand and the hockey stick resulting in improved grip, control and power transfer from the hands to the stick. 
     
     
         106 . A knob insert of any preceding claim inserted into a hollow end of the hockey stick wherein the tang having a longitudinal length roughly half the length of the overall knob insert while keeping the plurality of the knob insert and the handle of the hockey stick within the grip of the hand. 
     
     
         107 . A knob insert of any preceding claim inserted into a hollow end of the hockey stick wherein the tang, when fully inserted into the hollow end of a hockey stick, will generally not impact the flex of the stick. 
     
     
         108 . The knob insert of any preceding claims wherein the insert shaft is made of a material having the mechanical properties of Tensile Strength at yield, 73° of at least 18,000 psi using ASTM/ISO procedure D638. 
     
     
         109 . The knob insert of any preceding claims wherein the insert shaft is made of a material having the mechanical properties of Tensile Strength at yield, 73° of at least 19,000 psi using ASTM/ISO procedure D638. 
     
     
         110 . The knob insert of any preceding claims wherein the insert shaft is made of a material having the mechanical properties of Tensile Strength at yield, 73° of at least 21,000 psi using ASTM/ISO procedure D638. 
     
     
         111 . The knob insert of any preceding claims wherein the insert shaft is made of a material having the mechanical properties of Tensile Strength at yield, 73° of at least 23,000 psi using ASTM/ISO procedure D638. 
     
     
         112 . The knob insert of any preceding claims wherein the insert shaft is made of a material having the mechanical properties of Tensile Strength at yield, 73° of at least 26,000 psi using ASTM/ISO procedure D638. 
     
     
         113 . The knob insert of any preceding claims wherein the insert shaft is made of a material having the mechanical properties of Tensile Strength at yield, 73° of at least 29,000 psi using ASTM/ISO procedure D638. 
     
     
         114 . The knob insert of any preceding claims wherein the insert shaft is made of a material having the mechanical properties of Tensile Strength at yield, 73° of at least 31,000 psi using ASTM/ISO procedure D638. 
     
     
         115 . The knob insert of any preceding claims wherein the insert shaft is made of a material having the mechanical properties of Tensile Strength at yield, 73° of at least 33,000 psi using ASTM/ISO procedure D638. 
     
     
         116 . The knob insert of any preceding claims wherein the insert shaft is made of a material having the mechanical properties of Tensile Strength at yield, 73° of at least 37,000 psi using ASTM/ISO procedure D638. 
     
     
         117 . The knob insert of any preceding claims wherein the insert shaft is made of a material having the mechanical properties of Tensile Strength at yield, 73° of at least 41,000 psi using ASTM/ISO procedure D638. 
     
     
         118 . The knob insert of any preceding claims wherein the insert shaft is made of a material having the mechanical properties of Tensile Strength at yield, 73° of at least 45,000 psi using ASTM/ISO procedure D638. 
     
     
         119 . The knob insert of any preceding claims wherein the insert shaft is made of a material having the mechanical properties of Tensile Strength at yield, 73° of at least 50,000 psi using ASTM/ISO procedure D638. 
     
     
         120 . The knob insert of any preceding claims wherein the insert shaft is made of a material having the mechanical properties of Tensile Strength at yield, 73° of at least 70,000 psi using ASTM/ISO procedure D638. 
     
     
         121 . The knob insert of any preceding claims wherein the sheath comprises an anterior cantle region and a posterior cantle region. 
     
     
         122 . The knob insert of any preceding claims wherein the sheath comprises an anterior cantle region and a posterior cantle region, each of which gradually curves away from central longitudinal axis with sheath anterior cantle region having a radius of curvature R CASP1  in the sagittal plane that is less than the radius of curvature R CPSP1  of sheath posterior cantle region in the sagittal plane. 
     
     
         123 . The knob insert of any preceding claims wherein the sheath comprises an anterior cantle region and a posterior cantle region, each of which gradually curves away from central longitudinal axis with sheath anterior cantle region having a radius of curvature R CASP1  in the sagittal plane that is less than the radius of curvature R CPSP1  of sheath posterior cantle region in the sagittal plane and the ratio of R CPSP1  to R CASP1  is at least 2:1. 
     
     
         124 . The knob insert of any preceding claims wherein the sheath comprises an anterior cantle region and a posterior cantle region, each of which gradually curves away from central longitudinal axis with sheath anterior cantle region having a radius of curvature R CASP1  in the sagittal plane that is less than the radius of curvature R CPSP1  of sheath posterior cantle region in the sagittal plane and the ratio of R CPSP1  to R CASP1  is at least 3:1. 
     
     
         125 . The knob insert of any preceding claims wherein the sheath comprises an anterior cantle region and a posterior cantle region, each of which gradually curves away from central longitudinal axis with sheath anterior cantle region having a radius of curvature R CASP1  in the sagittal plane that is less than the radius of curvature R CPSP1  of sheath posterior cantle region in the sagittal plane and the ratio of R CPSP1  to R CASP1  is at least 4:1. 
     
     
         126 . The knob insert of any preceding claims wherein the sheath comprises an anterior cantle region and a posterior cantle region, each of which gradually curves away from central longitudinal axis with sheath anterior cantle region having a radius of curvature R CASP1  in the sagittal plane that is less than the radius of curvature R CPSP1  of sheath posterior cantle region in the sagittal plane and the ratio of R CPSP1  to R CASP1  is at least 5:1. 
     
     
         127 . The knob insert of any preceding claims wherein the sheath comprises an anterior cantle region and a posterior cantle region, each of which gradually curves away from central longitudinal axis with sheath anterior cantle region having a radius of curvature R CASP1  in the sagittal plane that is less than the radius of curvature R CPSP1  of sheath posterior cantle region in the sagittal plane and the ratio of R CPSP1  to R CASP1  is at least about 20:1. 
     
     
         128 . The knob insert of any preceding claims wherein the sheath comprises an anterior cantle region and a posterior cantle region, each of which gradually curves away from central longitudinal axis with sheath anterior cantle region having a radius of curvature R CASP1  in the sagittal plane that is less than the radius of curvature R CPSP1  of sheath posterior cantle region in the sagittal plane and the ratio of R CPSP1  to R CASP1  is in the range of about 4:1 to about 17.5:1. 
     
     
         129 . The knob insert of any preceding claims wherein the sheath comprises an anterior cantle region and a posterior cantle region, each of which gradually curves away from central longitudinal axis with sheath anterior cantle region having a radius of curvature R CASP1  in the sagittal plane that is less than the radius of curvature R CPSP1  of sheath posterior cantle region in the sagittal plane and the ratio of R CPSP1  to R CASP1  is in the range of about 5:1 to about 10:1. 
     
     
         130 . The knob insert of any preceding claims wherein the sheath has a radius of curvature, in the coronal plane on either side of the sagittal plane. 
     
     
         131 . The knob insert of any preceding claims wherein the sheath has a radius of curvature, in the coronal plane on either side of the sagittal plane which are asymmetrical. 
     
     
         132 . The knob insert of any preceding claims wherein the sheath has a radius of curvature, in the coronal plane on either side of the sagittal plane which are comparable. 
     
     
         133 . The knob insert of any preceding claims wherein the sheath has a radius of curvature, in the coronal plane on either side of the sagittal plane, which gradually curve away from the central longitudinal axis. 
     
     
         134 . The knob insert of any preceding claims wherein the sheath has a radius of curvature in the left coronal plane, R CCP1  and a radius of curvature in the right coronal plane, R CCP2  on either side of the sagittal plane. 
     
     
         135 . The knob insert of any preceding claims wherein the sheath has a radius of curvature in the left coronal plane, R CCP1  and a radius of curvature in the right coronal plane, R CCP2  on either side of the sagittal plane. 
     
     
         136 . The knob insert of any preceding claims wherein the sheath has a radius of curvature in the left coronal plane, R CCP1  and a radius of curvature in the right coronal plane, R CCP2  on either side of the sagittal plane are comparable and have a ratio of about 2:1 to about 1:2. 
     
     
         137 . The knob insert of any preceding claims wherein the sheath has a radius of curvature in the left coronal plane, R CCP1  and a radius of curvature in the right coronal plane, R CCP2  on either side of the sagittal plane are comparable and have a ratio of about 1.75:1 to about 1:1.75. 
     
     
         138 . The knob insert of any preceding claims wherein the sheath has a radius of curvature in the left coronal plane, R CCP1  and a radius of curvature in the right coronal plane, R CCP2  on either side of the sagittal plane are comparable and have a ratio of about 1.5:1 to about 1:1.5. 
     
     
         139 . The knob insert of any preceding claims wherein the sheath has a radius of curvature in the left coronal plane, R CCP1  and a radius of curvature in the right coronal plane, R CCP2  on either side of the sagittal plane are comparable and have a ratio of about 1.1:1 to about 1:1.1. 
     
     
         140 . The knob insert of any preceding claims wherein the shaft has a radius of curvature, in the coronal plane on either side of the sagittal plane. 
     
     
         141 . The knob insert of any preceding claims wherein the shaft has a radius of curvature, in the coronal plane on either side of the sagittal plane which are asymmetrical. 
     
     
         142 . The knob insert of any preceding claims wherein the shaft has a radius of curvature, in the coronal plane on either side of the sagittal plane which are comparable. 
     
     
         143 . The knob insert of any preceding claims wherein the shaft has a radius of curvature, in the coronal plane on either side of the sagittal plane, which gradually curve away from the central longitudinal axis. 
     
     
         144 . The knob insert of any preceding claims wherein the shaft has a radius of curvature in the left coronal plane, R CCP3  and a radius of curvature in the right coronal plane, R CCP4  on either side of the sagittal plane. 
     
     
         145 . The knob insert of any preceding claims wherein the shaft has a radius of curvature in the left coronal plane, R CCP3  and a radius of curvature in the right coronal plane, R CCP4  on either side of the sagittal plane. 
     
     
         146 . The knob insert of any preceding claims wherein the shaft has a radius of curvature in the left coronal plane, R CCP3  and a radius of curvature in the right coronal plane, R CCP4  on either side of the sagittal plane are comparable and have a ratio of about 2:1 to about 1:2. 
     
     
         147 . The knob insert of any preceding claims wherein the shaft has a radius of curvature in the left coronal plane, R CCP3  and a radius of curvature in the right coronal plane, R CCP4  on either side of the sagittal plane are comparable and have a ratio of about 1.75:1 to about 1:1.75. 
     
     
         148 . The knob insert of any preceding claims wherein the shaft has a radius of curvature in the left coronal plane, R CCP3  and a radius of curvature in the right coronal plane, R CCP4  on either side of the sagittal plane are comparable and have a ratio of about 1.5:1 to about 1:1.5. 
     
     
         149 . The knob insert of any preceding claims wherein the shaft has a radius of curvature in the left coronal plane, R CCP3  and a radius of curvature in the right coronal plane, R CCP4  on either side of the sagittal plane are comparable and have a ratio of about 1.1:1 to about 1:1.1. 
     
     
         150 . The knob insert of any preceding claims, wherein the tang has a cross-sectional shape that is any of polygonal, oval, and round. 
     
     
         151 . The knob insert of  claim 150 , wherein the tang has a cross-sectional shape that is a regular or irregular polygon. 
     
     
         152 . The knob insert of  claim 150 , wherein the tang has a cross-sectional shape that is any of triangular, square, rectangular, pentagonal, hexagonal, octagonal, oval and round.