Minimum 5-year follow-up surgical results of post-traumatic thoracic and lumbar kyphosis treated with anterior instrumentation: comparison of anterior plate and dual rod systems.

STUDY DESIGN

A retrospective follow-up study of post-traumatic thoracic and lumbar kyphosis after anterior instrumentation with anterior plate and dual rod systems.

OBJECTIVE

To investigate the outcome of anterior vertebrectomy, anterior strut grafting, and anterior instrumentation in patients with > 30 degrees sagittal contour deformity.

SUMMARY OF BACKGROUND DATA

Post-traumatic kyphosis may lead to mechanical pain due to the impairment of physiologic sagittal contours as well as cosmetic complaints.

METHODS

Forty patients with post-traumatic kyphosis were followed for a minimum of 5 years. Mean age was 44.7 +/- 12.4 years (range, 18-65 years); 18 were female and 22 were male. All patients underwent anterior vertebrectomy and decompression; anterior fusion was carried out with costal or iliac ala grafts. Patients were randomly assigned into 2 treatment groups: correction and internal fixation was performed by using either plate-screw (n = 20) or double rod-screw (n = 20). Patients were also evaluated clinically by using Pain and Functional Assessment Scale (PFA) and SRS-22 questionnaire.

RESULTS

Before surgery, the mean value for local sagittal contours was 51.4 degrees +/- 13.8 degrees; after surgery, it was reduced to 7.0 degrees +/- 7.6 degrees, resulting in an 88.7% +/- 11.3% correction (P = 0.00). At the last follow-up visit, a mean correction loss of 1.4 degrees +/- 1.8 degrees was found. A statistically significant improvement in local kyphosis angles and PFA scores was found after surgery and at the last visit. In 92.5% of the patients (n = 36), pain completely resolved; and in the remaining 3 patients, it is markedly reduced. Neurologic improvement was achieved in all of the 24 patients with neural claudication and other neurologic findings. Solid fusion mass was obtained in all patients. The type of instrumentation system did not differ significantly in terms of kyphotic deformity correction rates, correction losses, PFA scores, and SRS-22 scores. Final PFA scores showed a statistically significant correlation with SRS-22 scores (r = -0.918, P < 0.01). Final pain, function, mental status, self image and satisfaction domain scores and total SRS-22 score were > or = 4. The time from trauma to operation and the severity of kyphotic deformity were inversely correlated with postoperative correction rates. On the other hand, these 2 parameters were positively correlated with both final PFA and final SRS-22 scores (P < 0.01).

CONCLUSIONS

In light of the present study's findings, we suggest that the technique of anterior decompression, strut grafting, and anterior instrumentation is an effective method for the treatment of post-traumatic kyphotic deformity and that the success of the technique depends on the time from trauma to operation and the severity of baseline deformity, regardless of the type of instrumentation.