METHODS: Sixty-six consecutive patients who had primary thyroid surgery were prospectively included in the present study between late January and early August 1998.
RESULTS: A total of 96 capsular dissections were performed at thyroid surgery. Grades two and three ZT were recognized in 77 (80.2%) dissections. In general 49 (63.6%) of them were associated with significant pressure symptoms. In 43 (87.8%) of the dissections with pressure symptoms, grade 3 ZT was observed (mean weight of goitre: 154.8 g). Interestingly in this group, 16 (37.2%) patients with pressure symptoms had a goitre that was < 100 g and in one patient it was only 21 g.
CONCLUSIONS: The pressure symptom of the thyroid gland does not always appear to be due to the large size of the goitre. In a relatively small-size goitre the ZT may cause significant pressure symptoms. Observations in the present study supported a strong association of enlarged ZT with pressure symptoms. We believe this is unlikely to be simply a coincidence but rather a consequence of the enlarged tubercle. Nonetheless a prospective randomized study is called for to allow meaningful and objective evidence to be drawn.
METHODS: The scoliosis curves were divided into eight zones. CT scans were used to assess perforations: Grade 0, Grade 1( 4 mm). Anterior perforations were classified into Grade 0, Grade 1( 6 mm). Grade 2 and 3 (except lateral grade 2 and 3 perforation over thoracic vertebrae) were considered as 'critical perforations'.
RESULTS: 1986 screws in 137 patients were analyzed. The overall perforation rate was 8.4% after exclusion of the lateral perforation. The highest medial perforation rate was at the transitional proximal thoracic (PT)/main thoracic (MT) zone (6.9%), followed by concave lumbar (6.7%) and convex main thoracic (MT) zone (6.1%). The overall critical medial perforation rate was 0.9%. 33.3% occurred at convex MT and 22.2% occurred at transitional PT/MT zone. There were 39 anterior perforations (overall perforation rate of 2.0%). 43.6% occurred at transitional PT/MT zone, whereas 23.1% occurred at concave PT zone. The overall critical anterior perforation rate was 0.6%. 5/12 (41.7%) critical perforations occurred at concave PT zone, whereas four perforations occurred at the transitional PT/MT zone. There were only two symptomatic left medial grade 2 perforations (0.1%) resulting radiculopathy, occurring at the transitional main thoracic (MT)/Lumbar (L) zone.
CONCLUSION: Overall pedicle perforation rate was 8.4%. Highest rate of critical medial perforation was at the convex MT zone and the transitional PT/MT zone, whereas highest rate of critical anterior perforation was at the concave PT zone and the transitional PT/MT zone. The rate of symptomatic perforations was 0.1%.