Search

Background: The Bisurface knee prosthesis was designed in 1989 to improve knee flexion without affecting the durability of the prosthesis. The prosthesis has a unique ball-and-socket joint in the midposterior portion of the femoral and tibial components, which functions as a posterior stabilizing cam mechanism and causes femoral rollback. The femoral component was made of alumina ceramic. The purpose of this study was to review the clinical results of the first 223 arthroplasties performed with this prosthesis in order to assess whether this new implant had achieved its design objectives.Methods: From December 1989 to May 1994, all patients who were scheduled for primary total knee arthroplasty were enrolled in a prospective study of the Bisurface knee. The patients were evaluated clinically according to The Hospital for Special Surgery knee-rating system and with a self-administered questionnaire, and they were evaluated radiographically according to the system of the Knee Society. Kaplan-Meier survivorship analysis was performed with revision of the knee or recommendation for revision as the end point.Results: One hundred and sixty-six patients treated with a total of 223 consecutive primary total knee arthroplasties were enrolled in the study, and 182 knees were followed for 3.9 to 9.0 years (mean, 5.8 years). Preoperatively, the mean Hospital for Special Surgery knee score was 44.5 points. At the time of latest follow-up, the mean knee score was 86.3 points. The mean preoperative and postoperative ranges of flexion were 119 and 124 degrees, respectively. The patients, even those with a good preoperative range of motion, rarely lost deep flexion of the knee after the procedure. A revision operation was performed in eight knees (because of infection in five, instability in two, and breakage of the peg of the patellar component in one). Two knees had recurrent medial-lateral subluxations of the femorotibial articulation, which were treated nonoperatively. No prosthesis had loosened aseptically and no alumina ceramic femoral component had broken by the time of latest follow-up. The rate of survival of the implant was 94 percent (95 percent confidence interval, 90 to 98 percent) at six years. According to the patient questionnaires, 20 percent of the knees sometimes felt loose in daily living activities, which prompted us to improve the intrinsic stability of the prosthesis by improving the congruity of the ball-and-socket joint.Conclusions: Total knee arthroplasty with the Bisurface prosthesis resulted in an excellent range of motion and a high level of satisfaction with the operation; the durability of the prosthesis is promising. [ABSTRACT FROM AUTHOR]

Interpersonal violence is a major cause of maxillofacial fractures. The aim of this study was to analyze the characteristics of these fractures associated in an effort to develop more effective management. The clinical records and radiographs of 272 patients with maxillofacial fractures associated with interpersonal violence collected during a 36-year period were retrospectively analyzed. Two hundred and nineteen patients were male (80.5%) and 53 (19.5%) were female. The patients ranged in age from 1 to 77 years. Two hundred and two patients (74.3%) were aged 10 to 29 years. The injury was the result of impact by a fist/hand/elbow in 224 patients (82.3%). The fracture site was the mandible in 191 patients (70.2%), the midface in 78 (28.7%), and both sites in 3 (1.1%). One hundred and eight (39.6%) of 273 mandibular fractures were in the angle, 75 (27.5%) were in the symphysis, and 90 (33.0%) were at other sites. Forty-three (53.1%) of 81 fractures in the midface were in the zygoma, 19 (23.5%) were in the maxilla, and 19 (23.5%) were at other sites. Fractures were more common on the left side. Nine patients (3.3%) also had injuries at other body sites. Ninety-five patients (34.9%) were treated by maxillomandibular fixation, 84 (30.9%) by open reduction and internal fixation, 59 (21.7%) by observation, 14 (5.1%) by intramaxillary splinting, 14 (5.1%) by transcutaneous reduction, and 6 (2.2%) by other procedures. Interpersonal violence-related maxillofacial fractures have characteristic features, especially with regard to site and laterality.

Study Design: A cross-sectional study., Objective: To gain an insight into the prevalence, morphology, and distribution of thoracic ossification of the posterior longitudinal ligament of the spine (T-OPLL) by computed tomography (CT) and review of the literature., Summary of Background Data: The epidemiology and cause of T-OPLL remains obscure. To date, to the best of our knowledge, there is no study that has comprehensively evaluated the thoracic spine by CT to assess the prevalence, distribution, and morphology of T-OPLL in a sufficiently large size of sample with wide distribution of age., Methods: The participants of this study were the patients who have undergone chest CT for the examination of pulmonary diseases in our institute. The patients with previous thoracic spine surgery and younger than 15 years were excluded. Prevalence, distribution, and morphology of T-OPLL were reviewed., Results: A total of 3013 patients (1261 females and 1752 males) with the mean age of 65 years were recruited. The CT-based evidence of T-OPLL was noted in 56 (38 females and 18 males) individuals (1.9%). Most frequently encountered type was liner type, followed by continuous cylindrical type and mixed type. Continuous waveform and beaked type were less frequently encountered. Statistical analyses revealed that T-OPLL was noted at a significantly higher rate among the females. The mean age of T-OPLL-positive males was significantly higher than that of T-OPLL-negative males. Furthermore, there was significant difference of body mass index between T-OPLL-positive and T-OPLL-negative individuals. Most of T-OPLLs were confirmed in higher or middle thoracic regions and the highest peak was found at T3-T4. T-OPLL was noted after the age of 40 years with the peak distribution found at the age of 60 years., Conclusion: The prevalence of T-OPLL in Japanese was 1.9%. Further studies that characterize definitive subtypes of T-OPLL on CT are warranted so as to establish possible association between clinical manifestations and size and/or subtypes of T-OPLL., Level of Evidence: N/A.

Study Design: A cross-sectional study., Objective: To gain an insight for the prevalence, morphology, and distribution of thoracic ossification of the yellow ligament (OYL) by computed tomography (CT) and review of the literature., Summary of Background Data: The epidemiology and etiology of OYL remains obscure. To date, to the best of our knowledge, there is no study that comprehensively evaluated thoracic spine by CT to assess the prevalence, distribution, and morphology of OYL in a large enough sample size with wide age distribution., Methods: The participants of this study were the patients who have undergone chest CT for the examination of pulmonary diseases in our institute. The patients with previous thoracic spine surgery and younger than 15 years were excluded. Prevalence, distribution, and morphology of thoracic OYL were reviewed., Results: A total of 3013 patients (1261 females and 1752 males) with the mean age of 65 years were recruited. The CT-based evidence of OYL was noted in 1094 (428 females and 666 males) individuals (36%). Single-level involvement was noted in 532 cases, whereas 562 individuals presented multilevel involvement.Statistical analyses revealed that OYL was noted at a significantly higher rate among the males (P = 0.022). Of a total of 2051 OYLs, 779 central type OYLs, a mushroom-shaped ossification localized at the center of laminae, and 1272 noncentral type OYLs were noted. Distribution of the thoracic OYL formed 2 peaks with the highest and second highest peak found at T10-T11 and T4-T5, respectively. Interestingly, OYL is noted at consistent rates after the age of 30; however, its size increased in age-dependent manners., Conclusion: The prevalence of thoracic OYL in Japanese was 36%. A further study disclosing the association between clinical manifestations and size and/or morphology of OYL is warranted.

Maxillofacial fractures in Japanese children were retrospectively analyzed. The subjects were 287 patients aged 15 years and younger seeking treatment for maxillofacial fractures in the Department of Oral and Maxillofacial Surgery, Nara Medical University. The patients were 186 males and 101 females. Injuries most frequently occurred as a result of traffic accidents in 125 patients, 92 of which were bicycle-related accidents. Injuries by falling from one level to another were found in 49, primarily in younger children. One hundred seventy-nine fractures occurred in the mandible, 100 in the midface, and 8 in both. In the mandible, fractures most frequently occurred in condyle followed by symphysis. In the midface, alveolus was mostly involved. The facial injury severity scale ranged from 1 to 9 with an average of 1.83 and was higher in traffic accidents. Injury to other sites of the body was found in 33 patients, 28 of which occurred in traffic accidents. Observation was most frequently chosen in 84 patients. Intramaxillary fixation was chosen in 79, primarily for alveolar fractures and in younger children. Maxillomandibular fixation was chosen in 62 for mandibular fractures in older children. Open reduction and internal fixation was performed in 40, primarily in older children. The facial injury severity scale was higher in patients treated by open reduction and internal fixation and maxillomandibular fixation. Maxillofacial fractures in Japanese children showed characteristic features primarily depending on their age in terms of etiology, patterns, and treatment modalities.

Study Design: Clinical case series., Objective: To present a new innovative treatment option for cysts of the terminal ventricle., Summary of Background Data: Invasive surgery including laminectomy and cyst fenestration has been the sole reported method of treatment for this rare pathology., Methods: Four cases of symptomatic cyst of the terminal ventricle of the spinal cord were treated by percutaneous aspiration using real-time guidance with magnetic resonance imaging (MRI) and optically-tracking navigation., Results: Three patients were treated successfully by this percutaneous method, and for 1 patient the treatment was converted to conventional surgery after a single unsuccessful trial of percutaneous puncture. All patients were relieved of their symptoms without any complication. Follow-up MRI revealed continued shrinkage of the cysts after both surgery and MRI-guided percutaneous fenestration., Conclusion: MRI-navigated percutaneous aspiration can be a minimally-invasive treatment option for symptomatic cysts of the terminal ventricle, and therefore, can be indicated before more invasive surgery might be scheduled.