We evaluated the maturation of grafted bone in
cases of successful fusion after a one- or two-level posterior lumbar interbody
fusion (PLIF) using interbody carbon cages. We carried out a five-year
prospective longitudinal radiological evaluation of patients using
plain radiographs and CT scans. One year after surgery, 117 patients
with an early successful fusion were selected for inclusion in the
study. Radiological evaluation of interbody bone fusion was graded
on a 4-point scale. The mean grades of all radiological and CT assessments
increased in the five years after surgery, and differences compared
to the previous time interval were statistically significant for
three or four years after surgery. Because the grafted bone continues
to mature for three years after surgery, the success of a fusion
should not be assessed until at least three years have elapsed.
There were no significant differences in the longitudinal patterns
of grafted bone maturity between iliac bone and local bone. However,
iliac bone grafting may remodel faster than local bone.
We reviewed seven children with torticollis due to refractory atlanto-axial rotatory fixation who were treated in a halo vest. Pre-operative three-dimensional CT and sagittal CT imaging showed deformity of the superior articular process of C2 in all patients. The mean duration of halo vest treatment was 67 days (46 to 91). The mean follow-up was 34 months (8 to 73); at the latest review six patients demonstrated remodelling of the deformed articular process. The other child, who had a more severe deformity, required C1-2 fusion. We suggest that patients with atlanto-axial rotatory fixation who do not respond to conservative treatment and who have deformity of the superior articular process of C2 should undergo manipulative reduction and halo-vest fixation for two to three months to induce remodelling of the deformed superior articular process before C1-2 fusion is considered.
We have reviewed 1858 patients who had undergone a cervical laminoplasty and identified 43 (2.3%) who had developed a C5 palsy with a MMT (MRC) grade of 0 to 2 in the deltoid, with or without involvement of the biceps, but with no loss of muscular strength in any other muscles. The clinical features and radiological findings of patients with (group P; 43 patients) and without (group C; 100 patients) C5 palsy were compared. CT scanning of group P revealed a significant narrowing of the intervertebral foramen of C5 (p <
0.005) and a larger superior articular process (p <
0.05). On MRI, the posterior shift of the spinal cord at C4–5 was significantly greater in group P, than in group C (p <
0.01). This study is the first to correlate impairment of the C5 nerve root with a C5 palsy. It may be that early foraminotomy in susceptible individuals and the avoidance of tethering of the cord by excessive laminoplasty may prevent a post-operative palsy of the C5 nerve root.