Experimental Study Of The Stability And The Biomechanical Effect Of Radial Styloidectomy On The Wrist

Objective: To investigate the motion and the Stability biomechanicalchange of normal wrist and the wrist after Radial styloidectomy And toexplore the effect of Radial styloidectomy on the wrist and to providetheoretical base of the clinical treatment of the carpal disease. To provide atheoretical basis for the clinicalMethod: Eight fresh-frozen cadaver wrists were used. Deep cryogenicrefrigerator. Every specimens were confirmed no the carpal bone changes。Thearticular surface of the distal radius divided into radial and ulnar side andRadial side is divided into four parts.These specimens were placed on theCSS-44020biomechanical test machine,and were drived by the strength of100N with the speed of5㎜/s to make the movement of flexion、extension、radial deviation and ulnar deviation and checked the range of the wrists. In theback side of the wrist, Lister tubercle ulnar at about2~3cm incision along thedorsal margin of the distal radius Then the pressure sensitive films wereinserted into the wrists. Then Test change of the wrist biomechanical.Removal of the radial styloid,To investigate the motion and the Stability biomechanical change of wistResult:1The range of wrist movement.1.1the range of wrist movement have degrees when The radial styloidexcision3/4:Radial deviation, ulnar deviation, with large differences. The range ofactivities of the wrist After The radial styloid excision3/4: flexion was74.75°±2.65°extension was61.50°±3.274°radial deviation Was23.75°±3.15°ulnar deviation was37.88°±3.74°.2Changes of the biomechanics of the wrist.: 2.1The range of activities of the wrist After The radial styloid excision1/4and1/4:There was No statistically significant difference compared withnormal wrist.（P>0.05）2.2The range of activities of the wrist After The radial styloid excision3/4: The scaphoid fossa stress tend to concentrate, Stress transfer to the ulnar.3The lunate fossa highest pressure changes. The Wrist stability testscapholunate pitch, Carpal heigh ratio,thescapholunate angle changes havesignificant Statistically significant differenceConclusion: the wrist stability change is not statistically significantwhen The radial styloid excision range between0to1/2. When theexcised range of more than1/2The wrist stability obvious change The stress ismore concentrated, The stress is more concentrated and shift to the ulnar Thelunate withstand greater stress as potential factors for aseptic necrosis of thelunate bone We believe that the excision of the radial styloid process rests inbetween1/4to1/2...