Abstract
Background and Study Aims Single-level circumferential or pincer stenosis (PS) affects few patients with degenerative
cervical myelopathy (DCM). The surgical technique and medium-term results of a one-session
microsurgical 360-degree (m360°) procedure are presented.
Patients Between 2013 and 2018, the data of 23 patients were prospectively collected out of
371 patients with DCM. The m360° procedure comprised a microsurgical anterior cervical
decompression and fusion (ACDF), with additional plate fixation, followed by flipping
the patient and performing a microsurgical posterior bilateral decompression via a
unilateral approach in crossover technique.
Results The mean age of the patients was 72 years (range: 50–84); 17 patients were males.
The mean follow-up time was 12 months (range: 6–31). The patients filled in the patient-derived
modified Japanese Orthopaedic Association (P-mJOA) questionnaire on average 53 months
after surgery. One patient received a two-level ACDF. Lesions were mostly (92%) located
at the C3/C4 (8/24), C4/C5 (7/24), and C5/C6 (7/24) levels. Functional X-rays showed
segmental instability in 10 of 23 patients (44%). All preoperative T2-weighted magnetic
resonance imaging (MRI) showed an intramedullary hyperintensity. The median preoperative
mJOA score was 13 (range 3), and it improved to 16 (range 3) postoperatively. The
mean improvement rate in the mJOA score was 73%. When available, postoperative MRI
confirmed good circumferential decompression with persistent intramedullary hyperintensity.
There were two complications: a long-lasting radicular paresthesia at C6 and a transient
C5 palsy. No revision surgery was required.
Conclusion The one-session m360° procedure was found to be a safe surgical procedure for the
treatment of PS, and the medium-term clinical outcome was satisfactory.
Keywords degenerative cervical myelopathy - cervical spondylotic myelopathy - over-the-top
decompression - modified Japanese Orthopaedic Association score - pincer stenosis
