IN-TWIN

Study Summary

IN-TWIN: Traumatic Incomplete Tetraplegia Without Instability: a Prospective Multicenter Feasibility Study of Outcomes and Prognosis, is a multicenter, international, prospective, observational study under the collaboration of the AO Foundation, AO Spine, that seeks to obtain information and data that could inform the feasibility of administering a set of additional core and optional outcome assessments in cervical spinal cord injury (SCI) patients with incomplete tetraplegia without spinal instability to capture the aspects of neurologic impairment that may not be well represented in the standard motorsensory examinations.

Approximately 50 patients with acute traumatic cervical SCI are anticipated to enroll across all sites within 7 days of their injury.

Most studies on acute cervical spinal cord injuries (SCIs) tend to focus on more severely injured patients, i.e. those with American Spinal Injury Association (ASIA) Impairment Scale (AIS) Grade A to C. Despite being increasingly common, patients with "mild" injuries, i.e. cervical SCIs with less severe neurological deficits (AIS Grade D or sensory deficits only) with ongoing spinal cord compression but without instability of the spinal column are an understudied group in the field of SCI. 

One challenge in studying patients with milder forms of cervical SCI relates to identifying outcome measures that capture clinical changes. The International Standards for Neurologic Classification of Spinal Cord Injury (ISNCSCI) examination, despite being widely adopted and performed in most centers, focuses exclusively on motor/sensory functions and fails to assess other outcomes such as, gait impairment, neuropathic pain, spasticity, bladder dysfunction, and hand function/dexterity, all of which are important to patients with mild cervical injuries. This renders the ISNCSCI examination and AIS grading system insensitive in determining how treatment decisions could influence outcomes of these patients. Without a way to characterize the neurological impairments in a manner that is sensitive and responsive to change, it is extremely difficult to fill the knowledge gap of how to best manage this growing segment of SCI patients. 

The goal of this study is to obtain information and data that could inform the feasibility of administering a set of additional core and optional outcome assessments in cervical SCI patients with incomplete tetraplegia without spinal instability to capture the aspects of neurologic impairment that may not be well represented in the ISNCSCI examination.

Study Site Locations

  • University of California, San Francisco: Zuckerberg San Francisco General Hospital (San Francisco, California, United States of America)
  • Baltimore, Maryland, USA
  • Milwaukee, Wisconsin, USA
  • São Paulo, Brazil
  • Toronto, Canada
  • Vancouver, Canada
  • Murnau Am Staffelsee, Germany
  • New Delhi, India
  • Porto, Portugal

What is involved? 

  • ​Access to the patient's hospitalization records for the SCI visit. 
  • Assessments of gait and balance (the "Ten-Meter Walk Test" and Walking Index for Spinal Cord Injury, WISCI v2) during the initial hospital stay, and at 3 months and 6 months post-injury.
  • Assessments of hand strength and sensation (Graded Redefined
    Assessment of Strength Sensation and Prehension, GRASSP v2, digital dynamometer grip strength testing, and an assessment of pinch grip strength) during the initial hospital stay, and at 3 months and 6 months post-injury.
  • International Standard for Neurological Classification of Spinal Cord Injury (ISNCSCI) motor and sensory assessments conducted at 3 months and 6 months post-injury. 
  • Questionnaires on health and well-being (Short Form-36, SF-36 v2, and Spinal Cord Independence Measure, SCIM v3) conducted at 3 months and 6 months post-injury.
  • Pain assessment questionnaires (Neuropathic Pain Scale, NPS) conducted at 3 months and 6 months post-injury.  

Who can participate?

Patients who meet the following inclusion criteria are eligible for admission into the study:

  • ZSFG hospital admission less than 7 days from time of injury
  • Age 18 - 80
  • AIS grade D acute SCI involving neurological levels between C2 and C8 inclusive.
  • English speaking
  • Presence of spinal cord compression on the MRI
  • Absence of biomechanical instability to the extent that would mandate stabilization surgery by the treating surgeon
  • Ability to provide informed consent according to the IRB/EC defined and approved procedures