Object. Numerous surgical procedures have been developed for treatment of ossification of the posterior longitudinal ligament (OPLL) of the cervical spine, and these can be performed via three approaches: anterior, posterior, or combined anterior—posterior. The optimal approach in cases involving OPLL-induced cervical myelopathy, however, remains controversial. To address this issue, the authors assessed the benefits and limitations of expansive open-door laminoplasty for OPLL-related myelopathy by evaluating mid- and long-term clinical results. Methods. Clinical results obtained in 72 patients who underwent expansive open-door laminoplasty between 1983 and 1997 and who were followed for at least 5 years were assessed using the Japanese Orthopaedic Association (JOA) scoring system. The mean preoperative JOA score was 9.2 ± 0.4; at 3 years postoperatively, the JOA score was 14.2 ± 0.3 and the recovery rate (calculated using the Hirabayashi method) was 63.1 ± 4.5%, both having reached their highest level. These favorable results were maintained up to 5 years after surgery. An increase in cervical myelopathy due to progression of the ossified ligament was observed in only two of 30 patients who could be followed for more than 10 years. Severe surgery-related complications were not observed. Preoperative JOA score, age at the time of surgery, and duration between onset of initial symptoms and surgery affected clinical results. Conclusions. Mid-term and long-term results of expansive open-door laminoplasty were satisfactory. Considering factors that affected surgical results, early surgery is recommended for OPLL of the cervical spine.

Object. Ossification of the posterior longitudinal ligament (OPLL) often progresses after surgery, and this may cause late-onset neurological deterioration. There have been few studies, however, to clarify any correlation between progression and clinical outcome, partly because of the lack of studies involving reliable and reproducible methods by which detection of progression is made possible. The authors conducted a multicenter study to investigate the occurrence of postoperative progression and to elucidate the possible risk factors in a large-scale patient population, and a novel computer-assisted measurement method was used to provide the basis for future clinical studies. Methods. The authors analyzed lateral plain radiographs obtained immediately and at 1 and 2 years after surgery in 131 patients who underwent posterior decompression at 13 institutions. The x-ray films were transformed via scanner into digital images; the length and thickness of ossifications were measured using a new computer-assisted measurement system, and the incidence of progression was determined. Odds ratios for progression according to age group and types of OPLL were determined and compared to elucidate significant risk factors of progression. Conclusions. This is the first multicenter study to investigate the incidence of OPLL progression after posterior decompression by using a standardized measurement method. The rate of postoperative progression at 2 years was 56.5%, which was comparable with results reported in other studies. Progression occurred more frequently in younger-age rather than in older-age patient populations at both 1 and 2 years postoperatively. Mixed-type and continuous-type OPLL progressed more frequently than the segmental-type lesion at 2 years. The results of the present study could serve as basis for future studies to assess the efficacy of drug therapy to prevent OPLL progression.

The present study showed the beneficial effect of the exercise program aimed at improving flexibility, body balance, muscle power, and walking ability in preventing falls in the elderly.

Object. The segmental-type of ossification of the posterior longitudinal ligament (OPLL) of the cervical spine is distinct from other types in its morphological features. Whether the results of expansive open-door laminoplasty for the segmental-type are different from those for other types remains unclear. To clarify this issue, the long-term results after surgical treatment of segmental-type OPLL were compared with those of other types. Methods. Clinical results were documented in 57 patients who underwent expansive open-door laminoplasty and were followed for a minimum of 7 years, results were quantified using the Japanese Orthopaedic Association (JOA) scoring system to determine function. Segmental-type OPLL was observed in 10 patients (Group 1) and other types in 47 patients (Group 2). Preoperative JOA scores were not significantly different between the two groups. As many as 5 years after surgery, clinical results were favorable and maintained in both groups, and no significant intergroup difference in postoperative JOA scores was observed; however, after 5 years postoperatively, JOA scores decreased in both groups. The decrease was greater in Group 1, and a significant intergroup difference in JOA scores was demonstrated when analyzing final follow-up data. In Group 1, the authors found that the degree of late-onset deterioration relating to cervical myelopathy positively correlated with the cervical range of motion. Conclusions. The long-term results of expansive open-door laminoplasty in the treatment of segmental-type OPLL were inferior to those for other types. Cervical mobility may contribute to the development of late deterioration of cervical myelopathy.

Minodronate is a potent nitrogen-containing bisphosphonate that can be administered according to a monthly (every 4 weeks) dosing regimen. A 6-month, cluster-randomized, open-label, multicenter, crossover trial was conducted to test the preference of Japanese patients with osteoporosis for monthly bisphosphonate versus weekly bisphosphonate. One hundred and forty-seven patients (postmenopausal women and men) with primary osteoporosis were recruited at eight outpatient clinics. The clinics were randomized into two groups according to the dosing protocol-monthly minodronate followed by weekly alendronate or risedronate for a total of 24 weeks, or weekly alendronate or risedronate followed by monthly minodronate for 24 weeks. Patient preference for either the monthly or weekly bisphosphonate regimen was evaluated using a preference questionnaire. One hundred and fifteen patients (78.2 %) who completed the trial were processed for the analyses. Significantly more patients preferred the monthly bisphosphonate regimen (65.2 %) than the weekly bisphosphonate regimen (15.7 %) (P = 0.007). 'Dosing schedule fits lifestyle better' was the most common reason given for the patient preference for both the monthly (32.0 %) and weekly bisphosphonate (33.3 %) regimens. Significantly more patients found the monthly bisphosphonate regimen to be more convenient (73.0 %) than the weekly bisphosphonate regimen (13.9 %) (P < 0.0001). The safety profiles of the two regimens were similar. The present trial demonstrated a strong patient preference for and the convenience of the monthly bisphosphonate regimen over the weekly bisphosphonate regimen in Japanese patients with osteoporosis.