Atlantoaxial fixation using plate and screw method: a report of 160 treated patients.
ABSTRACT We review our experience with the use of the plate and screw method of fixation in the treatment of 160 patients with atlantoaxial instability during a 14-year period at our center. We previously described this method of fixation in 1994.
Between 1988 and 2001, 160 patients with atlantoaxial instability were treated with the use of a plate and screw method of fixation at the Department of Neurosurgery at King Edward Memorial Hospital in Bombay, India. The study group was composed of 91 males and 69 females (mean age, 23 yr; age range, 18 mo-79 yr). Atlantoaxial instability was a result of congenital abnormality in 132 patients (83%) and occurred after trauma in 28 patients (17%). All patients had mobile, completely reducible atlantoaxial dislocation. For 3 months postoperatively, a hard cervical collar was used. The mean follow-up period was 42 months (range, 4 mo-14 yr).
Three patients died in the postoperative phase. Successful stabilization of the atlantoaxial region was documented with dynamic radiography in the other 157 patients. There was no incidence of implant rejection. In one patient, one screw was found to be broken 18 months after surgery; however, firm bony fusion was documented in this patient. There were no neurological, vascular, or infective complications.
The plate and screw method of fixation with the use of intra-articular bone grafts in patients with atlantoaxial instability yielded a 100% fusion rate with a low incidence of complications.
Article: Modified C1 lateral mass screw insertion using a high entry point to avoid postoperative occipital neuralgia.[show abstract] [hide abstract]
ABSTRACT: For the past decade, a screw-rod construct has been used commonly to stabilize the atlantoaxial joint, but the insertion of the screw through the C1 lateral mass (LM) can cause several complications. We evaluated whether using a higher screw entry point for C1 lateral mass (LM) fixation than in the standard procedure could prevent screw-induced occipital neuralgia. We enrolled 12 consecutive patients who underwent bilateral C1 LM fixation, with the modified screw insertion point at the junction of the C1 posterior arch and the midpoint of the posterior inferior portion of the C1 LM. We measured postoperative clinical and radiological parameters and recorded intraoperative complications, postoperative neurological deficits and the occurrence of occipital neuralgia. Postoperative plain radiographs were used to check for malpositioning of the screw or failure of the construct. Four patients underwent atlantoaxial stabilization for a transverse ligament injury or a C1 or C2 fracture, six patients for os odontoideum, and two patients for C2 metastasis. No patient experienced vertebral artery injury or cerebrospinal fluid leak, and all had minimal blood loss. No patient suffered significant occipital neuralgia, although one patient developed mild, transient unilateral neuralgia. There was also no radiographic evidence of construct failure. Twenty screws were positioned correctly through the intended entry points, but three screws were placed inferiorly (that is, below the arch), and one screw was inserted too medially. When performing C1-C2 fixation using the standard (Harms) construct, surgeons should be aware of the possible development of occipital neuralgia. A higher entry point may prevent this complication; therefore, we recommend that the screw should be inserted into the arch of C1 if it can be accommodated.Journal of Clinical Neuroscience 10/2012; · 1.25 Impact Factor
Article: Clinical and radiological comparison of treatment of atlantoaxial instability by posterior C1-C2 transarticular screw fixation or C1 lateral mass-C2 pedicle screw fixation.[show abstract] [hide abstract]
ABSTRACT: We compared the clinical and radiological results of posterior atlantoaxial fixation surgery using transarticular screws to those using a polyaxial screw-rod system in 55 patients with symptomatic atlantoaxial instability. Patients underwent posterior C1-C2 fixation: 28 patients (group 1) underwent C1-C2 transarticular screw fixation and 27 patients (group 2) underwent C1 lateral mass-C2 pedicle screw fixation. Patients were followed-up for at least 24 months. The clinical and radiological results were evaluated in the early postoperative period and at 3, 6, 12 and 24 months after surgery. Long-term postoperative stability and bone fusion were examined. After surgery, 93% of patients in group 1 and 96% of patients in group 2 were free of neck pain. The solid fusion rates were 82% for group 1 patients and 96% for group 2 patients at 12 months (p<0.092). In group 1, three patients showed fibrous union. Four patients had hardware failure due to a screw malposition (one in group 1) and pseudoarthrodesis (two in group 1 and one in group 2). One patient in group 1 had cerebrospinal fluid leakage. One patient in group 2 had occipital neuralgia. One vertebral artery injury occurred during the screw placement in group 1 and another in group 2 during the muscle dissection. C1-C2 transarticular screw fixation and C1 lateral mass-C2 pedicle screw fixation both produced excellent results for stabilization of the atlantoaxial complex, but the radiological outcome tended to be superior in C1 lateral mass-C2 pedicle screw fixation.Journal of Clinical Neuroscience 07/2010; 17(7):886-92. · 1.25 Impact Factor
Article: Posterior C1-2 fusion with C1 lateral mass and C2 isthmic screws: accuracy of screw position, alignment and patient outcome.[show abstract] [hide abstract]
ABSTRACT: Transarticular screw fixation is seen as the "gold standard" in instrumented fusion of C1 and C2. However, drawbacks are the necessity of a reduction before instrumentation and a risk of vertebral artery injury. Therefore, C1 lateral mass and C2 isthmic screws are an alternative. The present study assessed the feasibility of C1-2 stabilization with C1 lateral mass and C2 isthmic screws and evaluated quality of life. All data of 35 consecutive patients treated from May 2006 to September 2009 were collected. Patients had C1 lateral mass and C2 isthmic screws. Twenty patients were operated on for traumatic instabilities, six for neoplastic instabilities, five for infectious instabilities and two each for degenerative and congenital instabilities. Sixty-six of 70 C1 screws had an ideal position, while four were placed suboptimal without the need for revision. Twelve of 68 C2 screws were not ideal but acceptable; one screw needed a surgical revision. There was one non-surgery related case of neurological deterioration after multilevel instrumentation. No vascular injuries occurred. Realignment was correct in all patients. After a median follow-up of 12 months, patients showed a reduction of pain, disability and improvements in EQ-5D items. SF36 data compared with a normative population and a historical cohort showed lower levels of function in all domains. C1-C2 instrumented fusion with lateral mass and isthmic screws is a safe procedure. Sufficient screw position and alignment was possible in all cases. Therefore, at our institution transarticular screws were abandoned in favor of C1 lateral mass and C2 isthmic screws.Acta Neurochirurgica 12/2011; 154(2):305-12. · 1.52 Impact Factor