Abstract
STUDY DESIGN: Retrospective, descriptive study.
OBJECTIVES: To describe the characteristics and outcomes of patients with spinal canal stenosis who suffer significant spinal cord injury (SCI) due to hyperextension injury of the cervical spine. To compare their characteristics and outcomes with all patients suffering traumatic cervical SCI and with the total cohort of patients admitted to a Spinal Injuries Unit for rehabilitation.
SETTING: Spinal Injuries Unit (SIU), Princess Alexandra Hospital, Brisbane.
METHODS: Demographic, injury and outcome data were obtained from an existing database and by review of the medical records of 575 patients admitted to and discharged from the SIU between July 1st, 1995 and July 1st 2002. Main outcome measures were: change in American Spinal Injury Association (ASIA) scale category, change in ASIA motor score, discharge Functional Independence Measure (FIM) score and change in FIM score, length of stay (LOS), primary means of mobility at discharge and discharge destination. Standard statistical methods were used to compare groups.
RESULTS: A total of 18 (3%) of the 575 patients were found to have cervical canal stenosis and hyperextension injury (the CCS/HI group). This represents 8% of the total group suffering traumatic injury to the cervical spinal cord (the total cervical trauma: TCT group, n = 225). This CCS/HI group was found to have a mean age at injury of 55.1 years compared to 37.1 and 37.8 years respectively for the TCT and total groups. Ninety-four percent of patients were found to have a neurological level at admission at C1-3 or C4-5 compared to 75.6% of the TCT group and only 5.6% of patients had an ASIA Impairment Category A lesion at admission compared to 38.7% of the TCT group. Falls (55.6%) was the most common cause of injury in the CCS/HI group with motor vehicle accidents (33.8%) most common in the TCT group.
The mean change in ASIA motor score between admission and discharge was 34.7 compared to 20.4 for the TCT group. Degree of impairment (measured by a change in ASIA Category) improved in 28% of patients and mean change in total FIM score was 41.3. There was no difference seen with the TCT group. LOS was shorter for these patients (111.1 days vs. 161.6 days). The primary means of mobility at discharge was “walking” for 50% of this group (compared to 28.4% for the TCT group) while the next most common means of mobility was “power wheelchair” at 28% (17% of TCT group). Most patients (55.4%) were discharged to their previous home following rehabilitation and 22.3% were discharged to another rehabilitation unit or acute hospital.
CONCLUSIONS: Patients with cervical spinal canal stenosis who suffer hyperextension injury constitute a distinct subgroup with the total group of traumatic cervical spinal cord injuries. This study suggests that they are older at the time of injury, have more rostral cervical injuries, are more likely to have incomplete injuries and that falls is the most common cause of injury. They have greater improvement in motor function but this does not appear to result in greater function at discharge as measured by the FIM. There appears to be a dichotomy with results for mobility at discharge with patients either being able to walk or requiring a power wheelchair. LOS in the SIU is shorter but a higher percentage are discharged to another hospital or rehabilitation unit.
These abstracts were prepared by Dr Robert J. Moore. Correspondence should be addressed to him at Spine Society of Australia, Institute of Medical and Veterinary Science, The Adelaide Centre for Spinal Research, Frome Road, Adelaide, South Australia 5000.