Ana amfani da kalmar ''quarter crack'' yawanci a yanayin lafiyar kofaton doki kuma tana nufin nau'in raunin kofato da ke faruwa a yankin kwata ko diddige na kofato. Musamman, tsaga kwata shine tsaga ko fissure a tsaye wanda ke faruwa a bangon kofato, yawanci yana farawa daga ƙungiyar jijiyoyin jini (yankin da kofato ya haɗu da fata) kuma yana shimfiɗa ƙasa. Irin wannan rauni na iya zama mai zafi sosai kuma yana iya shafar ikon doki na tafiya ko gudu cikin kwanciyar hankali. Jiyya yawanci ya ƙunshi gyaran takalmin gyaran kafa, da kuma magance duk wata matsala da ta shafi abinci ko sarrafa doki.