Primary treatment of atlantoaxial rotatory fixation in children: a multicenter, retrospective series of 125 cases.

OBJECTIVE: The primary treatment for atlantoaxial rotatory fixation (AARF) remains controversial. The aim of this study was to investigate the primary treatment for AARF and create an algorithm for primary treatment. METHODS: The authors analyzed the data of 125 pediatric patients at four medical institutions from April 1989 to December 2018. The patients were reported to have neck pain, torticollis, and restricted neck range of motion and were diagnosed according to the Fielding classification as type I or II. As a primary treatment, 88 patients received neck collar fixation, and 28 of these patients did not show symptom relief and required Glisson traction. Thirty-seven patients were primarily treated with Glisson traction. In total, 65 patients, including neck collar treatment failure patients, underwent Glisson traction in hospitals. RESULTS: The success rate of treatment was significantly higher in the Glisson traction group (97.3%) than in the neck collar fixation group (68.2%) (p = 0.0001, Wilcoxon test). In the neck collar effective group, Fielding type I was more predominant (p = 0.0002, Wilcoxon test) and the duration from onset to the first visit was shorter (p = 0.02, Wilcoxon test) than that in the neck collar ineffective group. Using multivariate logistic regression analysis with the above items, the authors generalized from the estimated formula: logit [p(success group by neck collar fixation group)|duration from onset to the first visit (x1), Fielding type (x2)] = 0.4(intercept) - 0.15x1 + 1.06x2, where x1 is the number of days and x2 = 1 (for Fielding type I) or -1 (for Fielding type II). In cases for which the score is a positive value, the neck collar should be chosen. Conversely, in cases for which the score is a negative value, Glisson traction should be the first choice. CONCLUSIONS: According to this formula, in patients with Fielding type I AARF, neck collar fixation should be allowed only if the duration from onset is ≤ 10 days. In patients with Fielding type II, because the score would be a negative value, Glisson traction should be performed as the primary treatment.

Medium-term clinical results of unicompartmental knee arthroplasty for the treatment for spontaneous osteonecrosis of the knee with four to 15 years of follow-up.

BACKGROUND: Unicompartmental knee arthroplasty (UKA) is an option for the treatment of spontaneous osteonecrosis of the knee (SONK). However, there are limited studies focusing on this area. This study presents medium-term clinical outcome data of UKA for SONK. METHODS: We reviewed 50 SONK knees in 48 patients that were treated by UKA. The mean age, height, and body weight were 73 years, 153 cm, and 57 kg, respectively. The mean follow-up was 8.4 years (range, four to 15 years). Preoperatively, we measured the size and the volume (estimated by width × length × depth) of the necrotic bone mass on T1-weighted magnetic resonance imaging. The clinical results were evaluated serially at follow-up visits radiographically and with the Knee Society Scoring (KSS) and Oxford Knee Scoring (OKS) systems. RESULTS: There were no revisions, re-operations, or major complications. The mean sizes of the necrotic lesions were 17.2 mm (14.7-22.3 mm) in width, 28.2 mm (6.2-34.7 mm) in length, and 11.3 mm (3.2-14.5 mm) in depth. The mean volume was approximately 5.4 cm3 (0.7-10.3 cm3). The mean flexion of the knee, KSS Knee Score, Function Score, and OKS increased from a preoperative 128.7-137.5°, 52.3-91.3, 39.7-90.2, and 21.6-40.2, respectively, at the latest follow-up. At the last follow-up, all patients had good or excellent OKS. CONCLUSIONS: This study demonstrates that UKA is a good option and is reliable for the treatment of SONK irrespective of necrotic bone mass size.

Characterizing the course of back pain after osteoporotic vertebral fracture: a hierarchical cluster analysis of a prospective cohort study.

This study demonstrated four distinct patterns in the course of back pain after osteoporotic vertebral fracture (OVF). Greater angular instability in the first 6 months after the baseline was one factor affecting back pain after OVF. PURPOSE: Understanding the natural course of symptomatic acute OVF is important in deciding the optimal treatment strategy. We used latent class analysis to classify the course of back pain after OVF and identify the risk factors associated with persistent pain. METHODS: This multicenter cohort study included 218 consecutive patients with ≤ 2-week-old OVFs who were enrolled at 11 institutions. Dynamic x-rays and back pain assessment with a visual analog scale (VAS) were obtained at enrollment and at 1-, 3-, and 6-month follow-ups. The VAS scores were used to characterize patient groups, using hierarchical cluster analysis. RESULTS: VAS for 128 patients was used for hierarchical cluster analysis. Analysis yielded four clusters representing different patterns of back pain progression. Cluster 1 patients (50.8%) had stable, mild pain. Cluster 2 patients (21.1%) started with moderate pain and progressed quickly to very low pain. Patients in cluster 3 (10.9%) had moderate pain that initially improved but worsened after 3 months. Cluster 4 patients (17.2%) had persistent severe pain. Patients in cluster 4 showed significant high baseline pain intensity, higher degree of angular instability, and higher number of previous OVFs, and tended to lack regular exercise. In contrast, patients in cluster 2 had significantly lower baseline VAS and less angular instability. CONCLUSIONS: We identified four distinct groups of OVF patients with different patterns of back pain progression. Understanding the course of back pain after OVF may help in its management and contribute to future treatment trials.

Proposal of new classification of femoral trochanteric fracture by three-dimensional computed tomography and relationship to usual plain X-ray classification.

PURPOSE: Classification of femoral trochanteric fractures is usually based on plain X-ray findings using the Evans, Jensen, or AO/OTA classification. However, complications such as nonunion and cut out of the lag screw or blade are seen even in stable fracture. This may be due to the difficulty of exact diagnosis of fracture pattern in plain X-ray. Computed tomography (CT) may provide more information about the fracture pattern, but such data are scarce. In the present study, it was performed to propose a classification system for femoral trochanteric fractures using three-dimensional CT (3D-CT) and investigate the relationship between this classification and conventional plain X-ray classification. METHODS: Using three-dimensional (3D)-CT, fractures were classified as two, three, or four parts using combinations of the head, greater trochanter, lesser trochanter, and shaft. We identified five subgroups of three-part fractures according to the fracture pattern involving the greater and lesser trochanters. In total, 239 femoral trochanteric fractures (45 men, 194 women; average age, 84.4 years) treated in four hospitals were classified using our 3D-CT classification. The relationship between this 3D-CT classification and the AO/OTA, Evans, and Jensen X-ray classifications was investigated. RESULTS: In the 3D-CT classification, many fractures exhibited a large oblique fragment of the greater trochanter including the lesser trochanter. This fracture type was recognized as unstable in the 3D-CT classification but was often classified as stable in each X-ray classification. CONCLUSIONS: It is difficult to evaluate fracture patterns involving the greater trochanter, especially large oblique fragments including the lesser trochanter, using plain X-rays. The 3D-CT shows the fracture line very clearly, making it easy to classify the fracture pattern.