Complications of thoracic pedicle screws in scoliosis treatment.
METHODS
A retrospective study.


OBJECTIVE
To analyze complications with thoracic pedicle screws in scoliosis treatment at our Department over a 3-year period (1999-2001).


BACKGROUND
The use of pedicle screws remains controversial for thoracic scoliosis for fear of complications.


METHODS
A total of 115 consecutive patients who underwent posterior fusion using 1035 transpedicular thoracic screws were reviewed. All patients presented a main thoracic scoliosis with a mean Cobb angle of 75.4 degrees (range, 60 degrees -105 degrees ). For thoracic screw placement, a mini-laminotomy technique was used, inserting a spatula inside the vertebral canal to palpate the borders of the pedicle. Postoperative CT scan was used in 25 patients (21.7%) to study a total of 311 screws, when the screw position was questionable.


RESULTS
An independent spine surgeon retrospectively reviewed medical records and radiographs of the patients, at a mean follow-up of 4 years. There were 18 screws misplaced (1.7%) in a total of 13 patients (11.3%). Screw malposition was symptomatic only in 1 patient (pleural effusion and fever) and asymptomatic in the other 12 cases (10.4%). Other complications included intraoperative pedicle fractures in 15 patients (13%), dural tears (without neurologic complications) in 14 cases (12.1%), and superficial wound infections in 2 (1.7%). Another operation for screw removal was performed in 5 patients (4.3%), due to pleural effusion (in 1 case), asymptomatic late lateral loosening of a malpositioned screw (in 1), and the possible future risks related the intrathoracic screw position despite the lack of any symptoms (in 3). Two cases (1.7%) were retreated due to wound infection, without removing instrumentation. There was no loss of correction at follow-up.


CONCLUSIONS
The thoracic pedicle screw placement in scoliosis patients requires utmost caution. The mini-laminotomy technique was beneficial in increasing safety of the procedure with an acceptable incidence of complications.
Di Silvestre
Mario
M
Spine Surgery Department, Istituti Ortopedici Rizzoli, Bologna, Italy. mario.disilvestre@ior.it
Parisini
Patrizio
P
Lolli
Francesco
F
Bakaloudis
Georgios
G
D000293:Adolescent; D000328:Adult; D001863:Bone Screws / Q000009:adverse effects* / Q000592:standards; D002648:Child; D004388:Dura Mater / Q000293:injuries; D006801:Humans; D016268:Internal Fixators / Q000009:adverse effects / Q000592:standards; D007796:Laminectomy / Q000379:methods / Q000592:standards; D008875:Middle Aged; D010996:Pleural Effusion / Q000209:etiology; D011183:Postoperative Complications / Q000209:etiology* / Q000473:pathology / Q000517:prevention & control; D012189:Retrospective Studies; D012600:Scoliosis / Q000601:surgery*; D016103:Spinal Fractures / Q000209:etiology; D013123:Spinal Fusion / Q000009:adverse effects* / Q000295:instrumentation*; D013530:Surgical Wound Infection / Q000209:etiology; D013904:Thoracic Vertebrae / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*