Pronation and/or Dorsiflexion of First Joint For Evaluation of Second Joint

Abstract

A method and apparatus for reliably positioning a 3-segment limb, such as a leg or arm for imaging and medical analysis, which can accommodate for the patient's “natural alignment”. The apparatus positions the limb in such a way that the position of the proximal segment is controlled while an known external torque is applied at a known rate to the distal segment. The location of each of the limb's three segments is recorded using either external or internal measurement techniques, and the relative motions between the proximal and intermediate segments are used in the orthopedic evaluation of the proximal joint. Furthermore, the relative motions between the intermediate and distal segments are used in the orthopedic evaluation of the distal joint. By applying a known torque at a known rate, clinicians will be provided with valuable information related to joint range of motion, stability, laxity, and compliance.

That which is claimed: 
     
         1 . An apparatus for evaluating leg movement characteristics of a patient, said patient having a leg, said leg including an upper and lower leg portion, a knee between said upper and leg portion, and a foot, and an ankle intermediate said lower leg portion and said foot, said apparatus comprising:
 a frame;   a first femur stabilizer assembly for selective attachment relative to said upper leg portion and for fixing said upper leg portion relative to said frame;   a first patella stabilizer assembly for selective attachment relative to said leg proximate said knee and for fixing said knee relative to said frame;   a foot support assembly for selective attachment relative to said foot and for maintaining said foot in dorsiflexion such that said ankle tends to be resistant to movement relative to said lower leg portion; and   a rotation assembly for rotating said foot relative to said frame while said foot support assembly is maintaining said foot in dorsiflexion.   
     
     
         2 . The apparatus as claimed in  claim 1 , wherein said foot support assembly includes a dorsiflexion wedge. 
     
     
         3 . The apparatus as claimed in  claim 1 , wherein said foot support assembly includes an ankle dorsiflexion adjustment feature which can be adjusted to further accommodate different natural alignment states of different ankles of patients. 
     
     
         4 . The apparatus as claimed in  claim 1 , wherein said foot support assembly further includes an ankle pronation feature to further accommodate different natural alignment states of different ankles of patients. 
     
     
         5 . The apparatus of  claim 1 , wherein said rotation assembly is configured to provide rotation of said foot by exerting a torque thereon, and further comprising measurement device configured to measure said torque. 
     
     
         6 . An apparatus for evaluating leg movement characteristics of multiple patients, each patient having a leg, said leg including an upper and lower leg portion, a knee between said upper and leg portion, a foot, and an ankle intermediate said lower leg portion and said foot, said apparatus comprising:
 a frame;   a first femur stabilizer assembly for selective attachment relative to said upper leg portion and for fixing said upper leg portion relative to said frame;   a first patella stabilizer assembly for selective attachment relative to said leg proximate said knee and for fixing said knee relative to said frame;   a foot support assembly for selective attachment relative to said foot and including an ankle dorsiflexion adjustment feature to accommodate different natural alignment states of different ankles of patients; and   a rotation assembly for rotating said foot relative to said frame while said foot support assembly is maintaining said foot to accommodate said different natural alignment states of different ankles of patients.   
     
     
         7 . The apparatus as claimed in  claim 6 , wherein said foot support assembly includes a dorsiflexion wedge. 
     
     
         8 . The apparatus as claimed in  claim 6 , wherein said foot support assembly includes an ankle dorsiflexion adjustment feature which can be adjusted to further accommodate different natural alignment states of different ankles of patients. 
     
     
         9 . The apparatus as claimed in  claim 6 , wherein said foot support assembly further includes an ankle pronation feature to further accommodate different natural alignment states of different ankles of patients. 
     
     
         10 . The apparatus of  claim 6 , wherein said rotation assembly is configured to provide rotation of said foot by exerting a torque thereon, and further comprising measurement device configured to measure said torque. 
     
     
         11 . An apparatus for evaluating leg movement characteristics of a patient, said patient having a leg, said leg including an upper and lower leg portion, a knee between said upper and leg portion, and a foot, and an ankle intermediate said lower leg portion and said foot, said apparatus comprising:
 a frame;   a first femur stabilizer assembly for selective attachment relative to said upper leg portion and for fixing said upper leg portion relative to said frame;   a first patella stabilizer assembly for selective attachment relative to said leg proximate said knee and for fixing said knee relative to said frame;   a foot support assembly for selective attachment relative to said foot and for maintaining said foot in pronation such that said ankle tends to be resistant to movement relative to said lower leg portion; and   a rotation assembly for rotating said foot relative to said frame while said foot support assembly is maintaining said foot in dorsiflexion.   
     
     
         12 . The apparatus as claimed in  claim 11 , wherein said foot support assembly includes a pronation wedge. 
     
     
         13 . The apparatus as claimed in  claim 11 , wherein said foot support assembly includes an ankle pronation adjustment feature which can be adjusted to further accommodate different natural alignment states of different ankles of patients. 
     
     
         14 . The apparatus of  claim 11 , wherein said rotation assembly is configured to provide rotation of said foot by exerting a torque thereon, and further comprising measurement device configured to measure said torque. 
     
     
         15 . An apparatus for evaluating leg movement characteristics of multiple patients, each patient having a leg, said leg including an upper and lower leg portion, a knee between said upper and leg portion, a foot, and an ankle intermediate said lower leg portion and said foot, said apparatus comprising:
 a frame;   a first femur stabilizer assembly for selective attachment relative to said upper leg portion and for fixing said upper leg portion relative to said frame;   a first patella stabilizer assembly for selective attachment relative to said leg proximate said knee and for fixing said knee relative to said frame;   a foot support assembly for selective attachment relative to said foot and including an ankle pronation adjustment feature to accommodate different natural alignment states of different ankles of patients; and   a rotation assembly for rotating said foot relative to said frame while said foot support assembly is maintaining said foot to accommodate said different natural alignment states of different ankles of patients.   
     
     
         16 . The apparatus as claimed in  claim 15 , wherein said foot support assembly includes a pronation wedge. 
     
     
         17 . The apparatus as claimed in  claim 15 , wherein said foot support assembly includes an ankle pronation adjustment feature which can be adjusted to further accommodate different natural alignment states of different ankles of patients. 
     
     
         18 . The apparatus of  claim 15 , wherein said rotation assembly is configured to provide rotation of said foot by exerting a torque thereon, and further comprising measurement device configured to measure said torque. 
     
     
         19 . A method for evaluating leg movement characteristics of a patient, said patient having a leg, said leg including an upper and lower leg portion, a knee between said upper and leg portion, and a foot, and an ankle intermediate said lower leg portion and said foot, said method comprising the steps of:
 A) providing an apparatus including an upper leg supporting portion and a foot support assembly, said foot support assembly for selective attachment relative to said foot;   B) supporting said upper leg portion of said patient with said upper leg supporting portion of said apparatus, and supporting said foot of said patient with said foot support assembly of said apparatus;   C) adjusting said foot support portion such that said foot of said patient is maintained in dorsiflexion such that said ankle tends to be resistant to movement relative to said lower leg portion;   D) rotating said foot support assembly relative to said upper leg supporting portion such that a torque is applied to said leg while said foot support assembly is maintaining said foot in dorsiflexion; and   E) measuring movement of said lower leg relative to said upper leg.   
     
     
         20 . The method as claimed in  claim 19 , wherein in step “C”, said foot of each of said patients is also maintained in pronation dorsiflexion such that said ankle tends to be resistant to movement relative to said lower leg portion. 
     
     
         21 . The method as claimed in  claim 19 , wherein in step “D”, a measured torque is applied to said foot support assembly. 
     
     
         22 . A method for evaluating leg movement characteristics of multiple patients, each patient having a leg, said leg including an upper and lower leg portion, a knee between said upper and leg portion, a foot, and an ankle intermediate said lower leg portion and said foot, said method comprising the steps of:
 A) providing an apparatus including an upper leg supporting portion and a foot support assembly, said foot support assembly for selective attachment relative to said foot;   B) supporting said upper leg portion of said patient with said upper leg supporting portion of said apparatus, and supporting said foot of each of said patients with said foot support assembly of said apparatus;   C) adjusting said foot support so as to accommodate different natural alignment states of different ankles of each of said patients;   D) rotating said foot support assembly relative to said upper leg supporting portion such that a torque is applied to said leg while said foot support assembly is maintaining said foot in pronation; and   E) measuring movement of said lower leg relative to said upper leg.   
     
     
         23 . The method as claimed in  claim 22 , wherein in step “C”, said foot of each of said patients is also maintained in pronation so as to accommodate different natural alignment states of different ankles of each of said patients. 
     
     
         24 . The method as claimed in  claim 22 , wherein in step “D”, a measured torque is applied to said foot support assembly. 
     
     
         25 . The method as claimed in  claim 22 , wherein in step “D”, a second measured torque is applied to said foot support assembly.