Surgical Stabilization

After traumatic SCI, surgical stabilization serves multiple purposes. Apart from the primary goal of decompression of neural structures, the restoration of mechanical stability can reduce pain, eliminate the need for a cervical collar or other activity restrictions, and facilitate nursing and other rehabilitation. The precise method of mechanical stabilization can be variable but consists of non-surgical rigid orthosis, versus open stabilization through a variety of anterior, posterior or circumferential instrumentation and fusion maneuvers.

Author YearCountry
Research Design
Score
Total Sample Size
Methods Outcome
Rimoldi et al.  (1992)

USA

Case Series

N=147

Population: Mean age: 30 yr; Gender: males=115, females=32; Level of injury range: T9-L5; Level of severity: complete=56, incomplete=91; Mean time since injury: 23 days.

Intervention: Participants who received surgical stabilization and/or decompression were retrospectively analyzed.

Outcome Measures: American Spinal Injury Association (ASIA) Impairment Scale (AIS); Operation time; Rehabilitation time; Complications.

1.     120 stabilizations were performed: 112 posterior and eight anterior.

2.     68 decompressions were performed: 34 posterior and 34 anterior.

3.     AIS motor score improved an average of eight points in participants with incomplete injury but did not improve in those with complete.

4.     AIS motor score improvement was positively correlated with earlier surgery and with performing stabilization before/instead of decompression.

5.     Operation time was shorter for sublaminar wires than Harrington rods and Drummond wires (292 min versus 297 min versus 351 min) and for posterior than anterior procedures (292-351 min versus 380 min).

6.     Rehabilitation time was shorter in participants stabilized with sublaminar wires than with Drummond wires or Harrington rods (73 versus 92 versus 119 days) and was longer in those requiring postoperative immobilization.

7.     Surgical complications (n=37) included kyphosis, pseudarthrosis, infection, pain, and hardware failure; these were correlated with later time-to-surgery.

8.     Non-surgical complications (n=19) included deep vein thrombosis, pulmonary embolism, and pressure sores; there was no correlation with time-to-surgery.

9.     Blood loss was greater in anterior than posterior procedures.

Bucci et al. (1988)

USA

Case Series

NInitial=49, NFinal=48

Population: Mean age: 30.3 yr; Gender: males=42, females=7; Injury etiology: motor vehicle accident=28, fall=7, sports=14; Level of injury: cervical.

Intervention: Individuals who underwent immobilization (n=20) or immobilization and fusion (n=28) following SCI. Outcomes were assessed at 3 mo.

Outcome Measures: Spinal Instability, Treatment Failure, Malalignment, Neurological Improvement, Neurological Deterioration.

1.     There were significantly more individuals in the immobilization group with spinal instability (p<0.01).

2.     There was no significant difference between groups in treatment failure, malalignment, neurological improvement or deterioration.

Capen et al., (1985)

USA

Case Series

NInitial=212, NFinal=166

Population: Mean age: 26.7 yr; Gender: males=179, females=43; Level of severity: complete=96, incomplete=99, normal=17.

Intervention: Participants who received surgical stabilization of the cervical spine were retrospectively analyzed. Stabilization involved posterior fusion (n=114), anterior fusion (n=88), or combined fusion (n=10).

Outcome Measures: Mortality, Complications, Neurological impairment, Stabilization maintenance.

 

1.     No perioperative mortality occurred in any of the groups.

2.     Complications were reported in the anterior group (n=18), posterior group (n=22), and combined group (n=3).

3.     Neurological impairment occurred in the anterior group (n=4) and posterior group (n=1), but not combined group.

4.     In the anterior group at 4 yr follow-up (n=59), six participants required graft replacement, 36 demonstrated loss of reduced alignment, and 36 demonstrated degenerative changes around the fusion mass.

5.     In the posterior group at 4 yr follow-up (n=98), four participants required rewiring, none demonstrated loss of reduced alignment, and two demonstrated degenerative changes around the fusion mass; 73 demonstrated significant extension of fusion mass beyond intended levels.

6.     In the combined group at 2 yr follow-up (n=9), no participants demonstrated issues with graft/wire, loss of reduced alignment, or degenerative changes around the fusion mass; two demonstrated extension of fusion mass beyond intended area.

Discussion

Non-operative methods of spine stabilization are sometimes used, especially for cervical spine injuries. Halo vest immobilization is most commonly indicated for injuries of the atlantoaxial joint or high cervical spine. To specifically assess individuals with sub-axial cervical spine injuries, Bucci et al. (1988) published a retrospective review of immobilization plus surgery versus immobilization with halo vest alone. Many of the nonsurgical individuals eventually required crossover to receive surgical treatment, and some experienced neurological worsening during halo vest application. As such, for this type of sub-axial cervical spine injuries, surgery is generally preferred to halo vest immobilization in sufficiently unstable injuries.

Rimoldi et al. (1992) assessed the effect of stabilization method on rehabilitation time in thoracolumbar SCI. Although the surgical constructs used are outdated and no longer in use, the finding that individuals judged to have a more mechanically stable construct, and whom were able to avoid orthosis use, may be generalizable.

Among individuals receiving surgical stabilization of the cervical spine, a common management dilemma is whether to provide stabilization from an anterior approach, a posterior approach, or both. Capen et al. (1985) published a retrospective analysis suggesting small proportions of neurologic worsening in each group; however, this study is of limited use today as the fixation techniques are no longer in use.

Conclusion

There is conflicting level 4 evidence (based on three case series: Bucci et al. 1988; Capen et al. 1985; Rimoldi et al. 1992) on the effectiveness of surgical and non-surgical mechanical stabilization methods post SCI. Methods described in the literature are quite dated and no longer used clinically.