Occipitocervical Reconstruction with the OMI Loop: Results of a Multicenter Evaluation

Introduction: Reconstruction of the unstable craniocervical junction remains a major challenge. Most existing fixation systems have one of the following disadvantages: a) need for complex bending of the implant; b) lack of flexibility to use either screw or cable/wire fixation and c) lack of a stabilizing cross–link. We present the 12 month followup of a multicenter evaluation of the OMI loop, a precontoured, titanium occipitocervical fixation system.

Methods: A total of 30 patients (11 M; 19 F) with rheumatoid arthritis (n = 14); trauma (n =7); metastatic tumor (n=3); Chiari (n=2); pseudoarthrosis/other (n=4) underwent occipitocervical reconstruction. Occipital fixation involved screws alone (n=20), wire/cable alone (n=7) or a combination of screw/cable (n=3). Cervical fixation involved transarticular screws (n=l), lateral mass screws (n=1) and wire/cable (n=29). Bone graft (most frequently autograft) was used in 25 cases. Bone cement was used to augment the fixation in 8 cases. Postoperative immobilization consisted of a hard collar in 23 cases and a halo in 7 patients.

Results: A solid reconstruction was achieved in all cases without evidence of hardware failure. There were no neurological complications. Two patients with quadriplegia and significant co–morbidities died of medical complications. There were 3 infections (2 superficial, one deep) which responded to dressings/antibiotics.

Conclusions: Our preliminary experience indicates that the OMI loop is a versatile, easy to use precontoured occipitocervical fixation device which is associated with excellent clinical results in a wide array of indications.