Fateful High Bar Competition

A 10 year old girl was referred from her general pediatrician due to persistent prickling und loss of muscle function in both legs. It all started after competing in school gymnastics, who could cling longest to the high bar hands-free in a bent position over the inguinae. Our patient won after 10 minutes, however she immediately felt paresthesia in lower legs and reduced muscle function in both legs when bending the knees.
In further medical history she denied having B-symptoms or infections within the last weeks.
Further history was completely normal: No regular medication, no allergies. The mother reported one brother of hers suffered from occasional paresthesia when crossing legs.

Good general condition. Examination of abdomen (especially lower abdominal and inguinal area), lungs, heart and osseous structures (pelvis, spine) without any pain, bruises, swelling, crepitation or other pathological findings.
Muscular strength: Quadriceps muscle right leg M1/5, left leg M3/5. Any other muscles of lower and upper extremities M5/5.
Sensibility: Right leg with hypesthesia around patellar bone. Left leg without any findings.
Reflexes: Patellar tendon reflex both legs not provokable, achilles tendon reflex symmetrical.
Stand/walk: Walking with straight legs possible. As soon as the knees were to be bent, there was a complete loss of strength (cf. video).