Given an abstract of a paper, generate a title for this paper such that conveys the key focus of the paper.

Example input: Abstract: Some patients converted from ventricular fibrillation to organized rhythms by defibrillation-trained ambulance technicians (EMT-Ds) will refibrillate before hospital arrival. The authors analyzed 271 cases of ventricular fibrillation managed by EMT-Ds working without paramedic back-up. Of 111 patients initially converted to organized rhythms, 19 (17%) refibrillated, 11 (58%) of whom were reconverted to perfusing rhythms, including nine of 11 (82%) who had spontaneous pulses prior to refibrillation. Among patients initially converted to organized rhythms, hospital admission rates were lower for patients who refibrillated than for patients who did not(53% versus 76%, P = NS), although discharge rates were virtually identical (37% and 35%, respectively). Scene-to-hospital transport times were not predictively associated with either the frequency of refibrillation or patient outcome. Defibrillation-trained EMTs can effectively manage refibrillation with additional shocks and are not at a significant disadvantage when paramedic back-up is not available.
Example output: Refibrillation managed by EMT-Ds
Example explanation: The abstract is about refibrillation and it is also mentioned in the abstract that it is managed by EMT-Ds. So it is an apt title.
Q: Abstract: Ball-and-socket ankle is a rare deformity associated with such pre-existing conditions as congenital shortening of the lower limb, coalition of tarsal bones, absent digital rays and aplasia or hypoplasia of the fibula. We have observed seven patients with this deformity for an average of six years from initial examination at 20 days to 3.5 years. Arthrography showed that the configuration of the ankle was apparently normal in patients under 10 months of age and that a ball-and-socket joint develops by four to five years of age, possibly in compensation for the loss of inversion and eversion caused by tarsal coalition. Ball-and-socket joint is therefore probably not congenital, but is an acquired deformity secondary to various pre-existing congenital conditions.
A:
Genesis of the ball-and-socket ankle.