1065 NEW DIAGNOSIS OF OBSTRUCTIVE SLEEP APNEA FOLLOWING ANTERIOR CERVICAL DISCECTOMY AND FUSION, WORSENED BY RHEUMATOID ARTHRITIS

Introduction Onset of obstructive sleep apnea (OSA) following anterior cervical discectomy and fusion (ACDF) has been published in a retrospective study of 12 patients. Association of obstructive as well as central sleep apnea with Rheumatoid arthritis (RA) affecting the cervical vertebrae has also been observed. Here we present a case of new diagnosis of OSA following ACDF and subsequent worsening caused by RA and further instrumentalization affecting the cervical spine. Report of Case A 66 yr old female with history of hypertension and rheumatoid arthritis and no prior diagnosis of OSA, underwent ACDF of C5-6 and C6-7 in 2012 due to progressive increase in pain, numbness and loss of grip strength in the right upper extremity. Postsurgically in recovery she was noted to have apneic episodes. Following discharge she underwent investigation with oximetry and subsequent polysomnography (PSG) and was diagnosed with mild OSA and placed of CPAP at 8cm H20. Two years later, her neurological symptoms worsened. Re Imaging showed pseudoarthrosis of C6-7 and autofusion of C3-5, likely from RA. She underwent C6-7 decompressive foraminotomy as well as C4-T2 posterior instrumented fixation. On recent followup with sleep medicine, her husband reported worsened snoring and increased apneic episodes. Since last PSG, she had lost 20-30lbs. On exam her Friedman score was 1. PSG demonstrated moderate OSA this time. POLYSOMNOGRAPHY 6/2012 POLYSOMNOGRAPHY 11/2018 Total sleep time (TST): 415 mins AHI: 13.7 [Supine 40.5, Off back 12.5] Mean O2: 95.6% PLMI: 0.0 /hr Total sleep time (TST): 440 mins AHI: 24.7 [Supine -, Off back 24.7] Mean O2: 95.3% PLMI: 0.0 /hr Conclusion Association of of OSA after ACDF has been investigated in the only retrospective study of 12 patients by Guilleminault. Development of positional dyspnea after ACDF was also reported by Zhang and associates. This case highlights, the need for prospective investigation to establish association between OSA and ACDF. It also highlights the association of RA and OSA, which have been reported in the past, due to reduced neck width, subluxation of C3-4 and compression of medulla by odontoid.