Hiroki Ushirozako

Treatment of popliteal cysts via arthroscopic enlargement of unidirectional valvular slits

Abstract Objective. The aim of the present study was to investigate the efficacy of arthroscopic enlargement of unidirectional valvular slits for the treatment of popliteal cysts and to evaluate potential factors affecting the outcomes of our arthroscopic procedure. Methods. Twenty-nine patients aged 43–77 years with popliteal cysts were treated with arthroscopic cyst decompression. Surgery was performed via two posterior portals after creating a transseptal portal. Rauschning and Lindgren clinical score, magnetic resonance images, and osteoarthritic grade were evaluated pre- and postoperatively, and cartilage degeneration class was confirmed via arthroscopy. The mean follow-up period was 22.9 ± 14.6 months (range, 9–60 months). Results. Twelve cysts disappeared completely (group D), while 16 reduced and one enlarged (group R) in size by the final follow-up. Twenty-two (75.9%) of 29 popliteal cysts diminished to a volume that was less than 10% of the preoperative volume. Clinical scores improved in 93.1% of the patients, and more patients (68.8%) in group R had positive joint effusion at the final follow-up compared with group D (17.7%; p < 0.01). Conclusions. Arthroscopic cyst decompression was effective in the treatment of symptomatic popliteal cysts. Intra-articular pathologies associated with joint effusion should be corrected simultaneously.

Snapping Knee Caused by Medial Meniscal Cyst

Snapping phenomenon around the medial aspect of the knee is rare. We present this case of snapping knee caused by the sartorius muscle over a large medial meniscal cyst in a 66-year-old female. Magnetic resonance images demonstrated a large medial meniscal cyst with a horizontal tear of the medial meniscus. Arthroscopic cyst decompression with limited meniscectomy resulted in the disappearance of snapping, and no recurrence of the cyst was observed during a 2-year follow-up period.

Changes of bone mineral density and serum pentosidine during a 27-month follow-up of monthly minodronate in osteoporotic patients

ABSTRACT Purpose: Monthly regimen of minodronate for osteoporosis more than two years has not been reported yet. The aim of this study is to elucidate the effect of monthly minodronate (M-MIN) on bone mineral density (BMD) and serum pentosidine (Pen) during 27 months. Materials and methods: The study consisted of 52 newly treated patients (73.3 ± 8.8 years) (new group) and 47 patients (75.9 ± 9.5 years) who were switched from either alendronate or risedronate (switch group). Monthly minodronate (50 mg/every 4 weeks) was administered for 27 months. Lumbar, femoral neck, and total hip BMDs and serum pentosidine were monitored at baseline and after 9, 18, and 27 months of treatment. Results: In the new condition, lumbar, neck, and total hip BMDs increased significantly by 9.07%, 3.15%, and 3.06%, respectively. Only the lumbar BMD significantly increased in the switch condition. Serum Pen increased in both groups in a time-dependent manner. In the group switch, multivariate logistic regression analysis revealed that the initial change in serum intact procollagen type I N-terminal propeptide (P1NP) at 9 months was an independent predictor of changes in neck and total hip BMDs at 27 months (OR = 1.039, 95% CI 1.003–1.077, p = 0.032 for neck and OR = 1.055, 95% CI 1.009–1.104, p = 0.020 for total hip). Conclusions: Monthly minodronate treatment increased BMDs in newly treated patients over 27 months. Serum Pen increased with M-MIN therapy, possibly indicating prolonged bone turnover. The initial 9-month changes in serum P1NP predicted the 27-month changes in hip BMDs when M-MIN replaced alendronate or risedronate.

Cut-off values of and factors associated with a negative influence on Neck Disability Index

PurposeThe Neck Disability Index (NDI) is used to evaluate patients with cervical spine disease. However, few reports have defined the cut-off values of the NDI. The purpose of this study was to identify the cut-off values of and factors with a negative impact on NDI.MethodsA total of 487 volunteers were divided into three groups based on disability: none, mild, and disabled. The cut-off values of the NDI were determined using receiver-operating characteristic curves. After these groups were divided based on sex and age adjustment was performed, the factors with a negative impact on NDI were investigated using multiple logistic regression analysis.ResultsGroups none, mild, and disabled included 207, 186, and 94 volunteers, respectively. The cut-off values of the NDI in each group were 0–5, 6–17, and ≥ 18%, respectively. After adjusting for age, groups none, mild, and disabled had 65, 56, and 23 males, respectively, and 92, 103, and 56 females, respectively. In multiple logistic regression analysis, the factors with a negative impact on NDI in males were manual work (odds ratio [OR] 1.924), higher T1 slope minus cervical lordosis (OR 1.043), and higher C2-7 sagittal vertical axis (OR 1.029, P < 0.05). Among females, the factors were hand-grip strength (OR 0.936), body fat percentage (OR 0.942), and sporting activity (OR 0.456, P < 0.05).ConclusionDeterioration in NDI was associated with cervical spinal malalignment and manual labor in males and lack of physical activity and sarcopenia in females.Graphical abstractThese slides can be retrieved under Electronic Supplementary Material.

Transcranial Motor Evoked Potential Monitoring for the Detection of Nerve Root Injury during Adult Spinal Deformity Surgery

Study Design Retrospective study. Purpose We aimed to determine the utility of transcranial motor evoked potential (TcMEP) monitoring for the detection of intraoperative nerve root injury. Overview of Literature Intraoperative neuromonitoring is important for the prediction of neurological injuries or postoperative paralysis. Nerve root injury can develop as a complication of adult spinal deformity (ASD) surgery. Methods We analyzed 295 patients who underwent ASD surgery using multi-channel TcMEP monitoring between 2010 and 2016 (58 men, 237 women; median age, 68 years; follow-up period ≥1 year). We defined the alarm point as a TcMEP amplitude <30% of that at baseline, and nerve root injury as meeting the focal TcMEP alerts shortly following surgical procedures with the presence of postoperative motor deficits in the selected muscles. Patients were classified into two groups, as those with nerve root injury and those with true-negatives. Results Seven patients (2.4%) exhibited neurological events related to nerve root injury, comprising six true-positive and one false-negative cases. TcMEP monitoring from multiple myotomes was effective in detecting nerve root injury. Compared to the 248 true-negative cases, the seven cases of nerve root injury were associated with significantly different preoperative pelvic tilt (PT) values, sacral slope values, and degree of change in PT. The cutoff for the degree of change in PT for predicting nerve root injury, with the best sensitivity and specificity, was 17.5°. Multivariate logistic analyses revealed that a change of >17.5° in PT (odds ratio, 17.5; 95% confidence interval, 1.994–153.560; p =0.010) was independently associated with intraoperative nerve root injury. Conclusions Multi-channel TcMEP monitoring may be useful for detecting nerve root injuries. A change in PT of >17.5° may be a significant risk factor for neurological events related to intraoperative nerve root injury.

Minimum Clinically Important Differences in Oswestry Disability Index Domains and Their Impact on Adult Spinal Deformity Surgery

Study Design Retrospective study. Purpose To calculate the minimum clinically important difference (MCID) for total and individual domains of the Oswestry Disability Index (ODI) and assess score distribution and changes over time in surgically treated adult spinal deformity (ASD) patients. Overview of Literature Despite the common use of ODI for assessing ASD, there are no robust studies defining MCID values for this index. Methods This study included 240 consecutive ASD patients with a minimum of 2 years of follow-up. We calculated MCID values for total and individual ODI domains using all or part of the Scoliosis Research Society-22R questionnaire as anchors. Using current MCID values, we measured the acquisition rates in patients who acquired MCID at follow-up in both total and individual ODI domains. Differences in pathology, age, and locations of the upper and lower instrumented vertebrae were analyzed. Results MCID of the total ODI score was 11%, with an area under the curve of 0.737. Each domain ranged from 0 to 2, with 1 being the most common value. In the pain and standing domains, >60% of the patients acquired MCID, although acquisition rates of the personal care, lifting, sleep, and sexual activity domains were relatively low (20%–35%). Patients with MCID had more radiographic improvement in lumbar lordosis, sagittal vertical axis, and T1 pelvic angle than those without MCID (p<0.05). Conclusions To our knowledge, this is the first study to describe MCID of ODI (11%) after ASD surgery. In the pain and standing domains, most patients acquired MCID although the rates of acquisition of MCID in the personal care, lifting, sleep, and sexual activity domains were low. Spine surgeons should counsel their patients regarding the benefits and setbacks of ASD surgery.

Arthroscopic Debridement of the Posterior Compartment of the Knee after Total Knee Arthroplasty

Arthroscopic debridement of the posterior compartment of the knee after total knee arthroplasty is difficult because it is tough to obtain intercondylar notch views. Herein, we performed arthroscopic debridement of the posterior compartment of an infected knee after total knee arthroplasty by using a transseptal portal in a 62-year-old woman with rheumatoid arthritis. Palpation of anatomical landmarks and posterior capsule protection are important for safe creation of a transseptal portal following to making 2 posterior portals.