Three main problems that can cause a luxating patella. 1  The first abnormality that is usually present is a trochlear groove that is too shallow. In order for the patella not to jump out of this tract, the groove must be deep enough to accommodate and cradle the patella as it moves up and down in the groove.
The longest river in South Africa is the Orange River which starts off life in the Drakensberg Mountains and works its way westwards to Alexander Bay and then onto the west coast of South Africa.
Updated May 28, 2017. This following is a list of the ten longest rivers in the world, according to the Times Atlas of the World. Only 111 miles apart, the Nile River in Africa is the longest river in the world in comparison to its runner-up, the Amazon River, located in South America. Discover some key facts about each river and their residence country, along with its length in miles and kilometers.