Surgical Management of Ossification of the Posterior Longitudinal Ligament

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.

Ossified posterior longitudinal ligament: management strategies and outcomes

PURPOSE

This study was designed to determine the management strategies and outcomes of ossification of the posterior longitudinal ligament (OPLL) of the cervical spine.

METHODS

One hundred twenty-one patients with radiologically proven OPLL including early form of OPLL (EOPLL) and hypertrophy of the posterior longitudinal ligament (HPLL) underwent surgical intervention either by the anterior procedure or posterior procedure from 1993 to 2002. The anterior approach with direct removal of OPLL was performed on 111 patients with one- or two-level OPLL, whereas expansive laminoplasty was performed as the choice posterior procedure on 10 cases with extensive OPLL. The surgery-related outcome was excellent or good for 88% and fair for 12%. This clinical improvement correlated well with the severity of the preoperative myelopathy. Two patients underwent the second anterior procedure after expansive laminoplasty. OPLL associated with dural ossification may show cerebrospinal fluid leakage after resection of the OPLL and dural ossification.

CONCLUSIONS

One- or two-level OPLL can be resected by an anterior approach with partial corpectomy, whereas expansive laminoplasty is indicated for multilevel compressive myelopathy due to OPLL. EOPLL and HPLL should be carefully examined with radiological workups because they are a prestage form of OPLL.