<prompt> Seddon grading is used for -Classification of nerve injuriesGrading of open fracturesClassification Potts paraplegiaGrading of severity of malignant bone tumours  <response>: Ans. is a c i.e., Classification of nerve injuries Classification Potts paraplegia o Seddons classification is used in :i Peripheral nerve injuryii Potts paraplegiaSeddons classification of nerve injurieso Seddon identified three types of injuries :1 Neuropraxia There is contusion of the peripheral nerve which causes reversible physiological nerve conduction block. The axis cylinder i.e., axon with its endoneurium is preserved. Thus, there is physiological conduction block without anatomic disruption. The injury is temporary and recovery is complete. It is seen in crutchpalsy, tourniquet palsy, and Saturday night palsy.2 Axonotemesis There is injury to axon but endoneurium is preserved. Spontaneous recovery is expected in some cases. This is seen in closed fractures and dislocations.3 Neurotemesis There is complete anatomical section of nerve. No recovery possible. It is seen in open wound.Seddons classification for potts paraplegiaEarly onset paraplegiaLate onset paraplegiaActive diseaseHealed diseaseOccurs within 2 yearsAfter 2 yearsCauseso Inflammatory edemao Granulation tissueo Tubercular abscesso Caseous tissueo Tubercular debrisCauseso Stenosis of vertebral canalo Internal gibbuso Infective endarteritiso Prolonged stretching of cord over deformityo Pathological dislocation 