Conservative management of ossification of the posterior longitudinal ligament. A review.

OBJECT Ossification of the posterior longitudinal ligament (OPLL) can result in significant myelopathy. Surgical treatment for OPLL has been extensively documented in the literature, but less data exist on conservative management of this condition. METHODS The authors conducted a systematic review to identify all reported cases of OPLL that were conservatively managed without surgery. RESULTS The review yielded 11 published studies reporting on a total of 480 patients (range per study 1-359 patients) over a mean follow-up period of 14.6 years (range 0.4-26 years). Of these 480 patients, 348 (72.5%) were without myelopathy on initial presentation, whereas 76 patients (15.8%) had signs of myelopathy; in 56 cases (15.8%), the presence of myelopathy was not specified. The mean aggregate Japanese Orthopaedic Association score on presentation for 111 patients was 15.3. Data available for 330 patients who initially presented without myelopathy showed progression to myelopathy in 55 (16.7%), whereas the other 275 (83.3%) remained progression free. In the 76 patients presenting with myelopathy, 37 (48.7%) showed clinical progression, whereas 39 (51.5%) remained clinically unchanged or improved. CONCLUSIONS Patients who present without myelopathy have a high chance of remaining progression free. Those who already have signs of myelopathy at presentation may benefit from surgery due to a higher rate of progression over continued follow-up.