KNEE BALANCER

• Main Author: KITO YUKARI
• Format: Patent
• Language: English; Japanese
• Published: 17.12.2015
• Subjects: BANDAGES, DRESSINGS OR ABSORBENT PADS; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF,TUBULAR STRUCTURES OF THE BODY, E.G. STENTS; FILTERS IMPLANTABLE INTO BLOOD VESSELS; FIRST-AID KITS; FOMENTATION; HUMAN NECESSITIES; HYGIENE; MEDICAL OR VETERINARY SCIENCE; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; PROSTHESES; TREATMENT OR PROTECTION OF EYES OR EARS

PROBLEM TO BE SOLVED: To facilitate insertion to a knee joint before completing ostectomy, and measure a balance of left and right ligaments and a distance change of a joint fissure when a constant pressure is continuously applied in the full range of motion from the extension to the flexion, and thereby perform ostectomy adjustment satisfactorily.SOLUTION: A paddle 50 of a knee balancer 10 is inserted between a tibia base plate BP and a thighbone distal end, while an upper paddle 54 is stored in a concave of a lower paddle 52. When a switch valve 62 is turned ON, nitrogen is sent into a gas cylinder 42 of an actuator 40 from a nitrogen supply source 60, and an elevating body 30 or the upper paddle 54 comes up. The upper paddle 54 comes into abutment with the thighbone distal end and lift it, however is tilted under the influence of a tensile strength of an inside collateral ligament MLa and an outside collateral ligament MLb. An interval distance H and a tilt between the lower paddle 52 and the upper paddle 54 of this time can electronically be sensed by a distance sensor 70 and an angle encoder 34. 【課題】 骨切除を完了する前の膝関節への挿入を容易にするとともに、伸展から屈曲の全可動域で連続して一定圧力を印加した際の左右の靭帯のバランスと関節裂隙の距離変化を測定し、骨切除調整を良好に行う。【解決手段】 ニーバランサ１０のパドル５０は、下パドル５２の凹面内に上パドル５４が収納された状態で、脛骨ベースプレートＢＰと大腿骨遠位端との間に挿入される。スイッチバルブ６２をＯＮとすると、窒素供給源６０から窒素がアクチュエータ４０の気体シリンダ４２に送り込まれ、昇降体３０ないし上パドル５４が上昇する。上パドル５４は、大腿骨遠位端に当接して持ち上げるが、内側側副靭帯ＭＬａ及び外側側副靭帯ＭＬｂの引っ張りの強さの影響を受けて傾く。このときの下パドル５２と上パドル５４との間隔距離Ｈ及び傾きθは、距離センサ７０及び角度エンコーダ３４によって電子的に知ることができる。【選択図】図１