The Philadelphia Collar is a rigid two-piece cervical orthosis used by orthopaedic surgeons, emergency physicians and physiotherapists to immobilise the cervical spine. It limits flexion extension and rotation of the neck following trauma, during post-operative stabilisation and neurological management. The lightweight medical-grade EVA foam construction provides firm cervical support but is comfortable for the patient during extended use. Radiolucent construction enables X-ray and MRI imaging without removal of the collar during the clinical assessment period.