1.5 zomangira zokha

Ma mbale otsika otsika kwambiri opindika m'mphepete komanso mbiri yamba yotakata sizingamveke bwino. Ikupezeka muutali wokhazikika kwambiri.

Ubwino wa titaniyamu zomangira aloyi:

1. Mphamvu zapamwamba. Kachulukidwe wa titaniyamu ndi 4.51g/cm³, wokwera kuposa wa aluminiyamu komanso wocheperapo kuposa wachitsulo, mkuwa ndi faifi tambala, koma mphamvu zake ndizokwera kwambiri kuposa zitsulo zina. Zopangira zopangira titaniyamu ndi zopepuka komanso zamphamvu.
2. Kukana kwa dzimbiri kwabwino, titaniyamu ndi titaniyamu aloyi m'ma media ambiri ndizokhazikika kwambiri, zomangira za titaniyamu zitha kugwiritsidwa ntchito kumadera osiyanasiyana owononga mosavuta.
3. Kutentha kwabwino kwa kutentha ndi kutsika kwa kutentha. Zomangira za alloy za Titanium zimatha kugwira ntchito kutentha mpaka 600 ° C ndi kuchotsera 250 ° C, ndipo zimatha kusunga mawonekedwe awo popanda kusintha.
4. Non-magnetic, non-toxic.Titanium ndi chitsulo chosapanga maginito ndipo sichidzapangidwa ndi maginito m'madera okwera kwambiri a maginito.Osati omwe alibe poizoni, ndipo ali ndi mgwirizano wabwino ndi thupi la munthu.
5. Poyerekeza ndi chitsulo ndi mkuwa, titaniyamu imakhala ndi nthawi yayitali kwambiri yochepetsera kugwedezeka pambuyo pa kugwedezeka kwa makina ndi kugwedezeka kwamagetsi. Izi zingagwiritsidwe ntchito ngati mafoloko akukonzekera, zigawo za vibration za mankhwala akupanga grinders ndi mafilimu ogwedezeka a zokuzira zomvera zapamwamba.

Mapangidwe a ulusi poyambira wononga mwachangu komanso torque yotsika. Kusankhidwa kwakukulu kwa mbale ndi ma mesh, kuphatikiza ma mastoid ndi ma meshes akanthawi, ndi zovundikira mabowo otsekera.

Kulimba kowononga, kuli bwino?

Zitsulo zimagwiritsidwa ntchito kwambiri pa opaleshoni ya mafupa kuti aphimbe malo ophwanyidwa, kukonza mbale ku fupa, ndi kukonza fupa kumalo opangira mkati kapena kunja.

Komabe, pamene mphamvu ya torque ikuwonjezeka, screw imapeza mphamvu yaikulu ya torque (Tmax), panthawi yomwe mphamvu yogwiritsira ntchito wononga pa fupa imachepetsedwa ndipo imatulutsidwa patali pang'ono.Kutulutsa mphamvu (POS) ndiko kukanikiza kupotoza wononga fupa. Nthawi zambiri amagwiritsidwa ntchito ngati chizindikiro kuti ayese mphamvu yogwiritsira ntchito screw.Pakali pano, mgwirizano pakati pa torque yaikulu ndi mphamvu yokoka sichidziwikabe.

Zachipatala, madokotala a mafupa nthawi zambiri amaika wononga ndi pafupifupi 86% Tmax.Komabe, Cleek et al. anapeza kuti 70% Tmax screw kuyika pa tibia wa nkhosa akhoza kukwaniritsa pazipita POS, kusonyeza kuti mphamvu torsion mopitirira muyeso angagwiritsidwe ntchito kuchipatala, zomwe zingachepetse kukhazikika kwa fixation.

Kafukufuku waposachedwa wa humerus mu cadavers aumunthu ndi Tankard et al. anapeza kuti POS yochuluka inapezedwa pa 50% Tmax. Zifukwa zazikulu za kusiyana kwa zotsatira zomwe zili pamwambazi zikhoza kukhala kusagwirizana kwa zitsanzo zomwe zimagwiritsidwa ntchito komanso miyeso yosiyana.

Chifukwa chake, Kyle M. Rose et al. ochokera ku United States anayeza ubale pakati pa Tmax ndi POS zosiyanasiyana ndi zomangira zomwe zimayikidwa mu tibia ya cadavers za anthu, komanso kusanthula ubale pakati pa Tmax ndi BMD ndi makulidwe a fupa la cortical. ndi yayikulu kwambiri kuposa ya 100% Tmax. Panalibe kusiyana pakati pa BMD ndi makulidwe a cortical pakati pa magulu a tibia, ndipo panalibe mgwirizano pakati pa Tmax ndi ziwirizi. Ngakhale 70% ndi 90% Tmax imatha kukwaniritsa POS yofananira, pali zabwino zina pakuwonjeza wononga, koma torque siyenera kupitilira 90%, apo ayi zotsatira zake zidzakhudzidwa.

Chitsime: Ubale Pakati pa Insertional Torque ndi Pullout Strength of Surgical Screws.Techniques in Orthopaedics: June 2016 - Volume 31 - Issue 2 - p 137-139.