Different standing postures are the influencing factors for the efficacy of laminoplasty in the treatment of K-Line (−) patients with ossification of the posterior longitudinal ligament

Abstract

Abstract Objective To investigate the relationship between different standing postures and surgical outcomes of K-Line (−) ossification of the posterior longitudinal ligament (OPLL) patients after laminoplasty with a titanium basket. Summary of Background Data There is a lack of data evaluating the relationship between the postoperative satisfaction of K-Line (−) patients and their standing postures. Methods OPLL patients enrolled in the study were divided into a K-Line (+) group (Group A) and a K-Line (− group (Group B) in natural and relaxed standing positions. We compared the postoperative outcomes after cervical laminoplasty with titanium basket surgery using the Japanese Orthopaedic Association score (JOA), recovery rate and the degree of improvement in the six JOA score items. The degree of satisfaction with the outcome was assessed at the 1-year follow-up using a 7-point numerical rating scale. Results A total of 34 K-Line (+) patients with OPLL (age 61.9 ± 2.9 years) in Group A and 40 K-Line (−)patients with OPLL (age 60.4 ± 3.5 years) in Group B in natural and relaxed standing positions were recruited. In Group A, the mean preoperative and postoperative JOA scores were 10.1 ± 1.4 and 13.1 ± 0.8 points, respectively, and in Group B, the mean preoperative and postoperative JOA scores were 9.7 ± 1.3 and 11.1 ± 0.9 points, respectively. A significant improvement in the JOA score was seen in both groups postoperatively, but the recovery rate of the patients’ JOA scores was significantly lower in Group B. In Group A, significant improvements were seen in all JOA score items, but in Group B, improvements were seen only in upper- and lower-extremity sensory functions. Conclusion Different standing postures are risk factors in the treatment of K-Line (−) patients, and therefore, natural and relaxed standing positions should be given more attention before devising the surgical plan.