NHS provided equipment failed through course of normal use causing accident - England

My daughter (20) has special needs and attends a special needs college in England. To help with her mobility she uses a “crocodile walker” to get about at college. When not using the walker she is a wheelchair user.

This crocodile walker was supplied by the NHS following an assessment and subsequent set-up / configuration by an occupational therapist.

Yesterday, the supporting arm sheared off causing my daughter to fall to the floor and land on her hip. Fortunately it appears that no bones are broken. However my daughter is now in a lot of pain and is very scared of moving / walking. She is also requiring extra support at home to keep her mobile / bathed / toiletted.

As well as needing the walker replaced, I need to understand why and how the equipment failed, what can be done to ensure any replacement doesn’t fail in the same way, and to seal immediate extra support whilst she recovers.

What’s the best way of approaching this and who should I contact?