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1.
RSC Adv ; 12(32): 20714-20720, 2022 Jul 14.
Article in English | MEDLINE | ID: mdl-35919137

ABSTRACT

The fluorescence spectral fingerprint, also known as the excitation-emission matrix (EEM), is used to assess and visualize therapeutic drug photodegradation in combination with chemometrics. Examination of EEM-parallel factor analysis (PARAFAC) data showed that an individual component was easily separated from a mixture of photogenerated products of a heterocyclic pharmacophore, in this case, phenothiazine drugs (PTZs). Detailed investigations of both structure-EEM relationships and kinetics revealed that the components extracted from EEM-PARAFAC could be quantitatively attributed to such photogenerated products as phenothiazine sulfoxide and carbazole derivatives. EEM in combination with principal component analysis (PCA) could be used as a mapping tool to visualize information of the photodegradation process of PTZs. We also assessed the photostability of various types of PTZs containing side chains by using validated EEM-PARAFAC methodology.

2.
Phys Med Biol ; 64(12): 125003, 2019 06 10.
Article in English | MEDLINE | ID: mdl-31096205

ABSTRACT

Some recently developed brain-dedicated positron emission tomography (PET) scanners measure subjects in a sitting position. Sitting enables PET scanning under more natural conditions for the subjects and also helps with making the scanners smaller. It is unclear, however, how much the degree of head motion when sitting differs from the supine posture commonly employed in clinical PET. In this report, we describe development of a markerless and contactless head motion tracking system and a study of healthy volunteers in several different postures to determine the optimum posture for brain PET. We used Kinect® (Microsoft) and developed software that can measure head motion with about 1 mm (translation) and less than 1° (rotation) accuracy. In the volunteer study, we measured the amount of head motion, with and without head fixation, in supine, normal sitting, and reclining postures. The results indicated that the normal sitting posture without head fixation had the largest head movement, and that the reclining and supine postures were similarly effective for minimizing head movement (average head movement of about 0.5 mm during 1 min). We also visualized the influence that head motion had on images for each pose by simulating the actual motions obtained from the volunteer study using a digital Hoffman phantom. Comparisons with the original image showed that the extent to which motion was reduced in the reclining and supine postures were quantitatively equivalent. The head motions of the volunteer studies were also reproduced using a mannequin head on a motorized stage to assess how well the proposed motion measurement system worked when used for motion correction. The results indicated that even though the system improved image quality for all postures, the reclining and supine postures could provide better image quality than the normal sitting posture.


Subject(s)
Brain/diagnostic imaging , Positron-Emission Tomography/methods , Sitting Position , Supine Position , Adult , Female , Head Movements , Humans , Male , Phantoms, Imaging , Rotation , Software , Young Adult
3.
J Foot Ankle Surg ; 54(1): 37-40, 2015.
Article in English | MEDLINE | ID: mdl-25459094

ABSTRACT

Inadequate primary treatment of calcaneal fractures frequently results in persistent, residual pain. This can be caused by subtalar arthritis, an increased calcaneal width, and/or calcaneal fibular impingement of the peroneal tendons. Many patients experience multiple disorders simultaneously, requiring a combination of procedures to treat the injury. The purpose of the present study was to evaluate the clinical outcomes of arthroscopic debridement with lateral calcaneal ostectomy for residual pain after a calcaneal fracture. Four feet (4 patients) were treated with arthroscopic debridement and lateral calcaneal ostectomy. The patients were 3 males and 1 female, with a mean age of 55.3 ± 14.1 years. The mean follow-up duration was 33.5 ± 10.5 months postoperatively. Three patients received worker's compensation as a result of their condition. The patients were examined for improvement in pain levels using the numeric pain intensity scale and healing was assessed using the Japanese Society of Surgery of the Foot score. The mean Japanese Society of Surgery of the Foot score improved from 64.5 ± 13.8 preoperatively to 82.5 ± 7.1 postoperatively. The mean postoperative numeric pain intensity scale score was 2.3 ± 1.9. No complications, such as deep infection or problems with wound healing, were observed in any of the patients. The simultaneous use of arthroscopic subtalar debridement and lateral calcaneal ostectomy is a valuable intervention for the treatment of residual pain after a calcaneal fracture in patients who present with increased calcaneal width and mild or no degenerative changes in the subtalar joint.


Subject(s)
Calcaneus/surgery , Fractures, Bone/surgery , Adult , Aged , Arthroscopy , Calcaneus/injuries , Debridement , Female , Fractures, Bone/complications , Humans , Male , Middle Aged , Osteotomy , Pain/etiology , Pain/surgery , Talus/surgery
4.
J Orthop Surg Res ; 9: 93, 2014 Oct 10.
Article in English | MEDLINE | ID: mdl-25300562

ABSTRACT

BACKGROUND: Cam-type femoroacetabular deformity in acetabular dysplasia (AD) has not been well clarified. The primary purpose of this study was to determine the prevalence and characteristics of femoroacetabular deformity in symptomatic AD patients. METHODS: We retrospectively reviewed the cases of 86 women (92 hips) and eight men (eight hips) with symptomatic AD. The mean patient age was 37.9 (range, 14-60) years. All participants underwent lateral cross-table and lateral whole-spine radiographic examinations to measure the alpha angle and pelvic tilt. Pelvic computed tomography scans were used to measure femoral anteversion. The patients were classified into two groups: AD only group, containing hips with an alpha angle less than 55°; and AD with cam-type femoroacetabular deformity (AD + cam-type deformity) group, containing hips with an alpha angle greater than or equal to 55°. RESULTS: Of the patients with AD, 40 hips displayed additional radiographic evidence of cam-type morphology, while 60 hips had exclusive AD morphology. The patients in the AD + cam-type deformity group had significantly increased forward pelvic tilt in the standing position (p = 0.023) and decreased femoral anteversion (p =0.047) compared with the AD only group. CONCLUSIONS: Our data revealed that 40% of patients with AD also had radiographic evidence of cam-type femoroacetabular deformity. Greater forward pelvic tilt in the standing position and decreased femoral anteversion seemed to be associated with the cam-type deformity in these patients. These results indicate the morphological features that are most likely to induce secondary symptoms to developmental hip dysplasia. It is suggested that the symptoms in the AD + cam-type deformity group could arise through femoroacetabular impingement (FAI) after periacetabular osteotomy, because a predisposition was present preoperatively.


Subject(s)
Acetabulum/pathology , Femoracetabular Impingement/epidemiology , Acetabulum/diagnostic imaging , Adolescent , Adult , Biomechanical Phenomena , Case-Control Studies , Female , Femoracetabular Impingement/diagnostic imaging , Femoracetabular Impingement/physiopathology , Humans , Middle Aged , Pelvic Bones/physiopathology , Prevalence , Retrospective Studies , Tomography, X-Ray Computed , Young Adult
5.
Foot Ankle Int ; 34(3): 434-8, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23520302

ABSTRACT

BACKGROUND: The safety of posterior ankle arthroscopy is still the subject of debate. The purpose of this study was to evaluate the anatomical relationship between the posterior portals and the neurovascular structures using magnetic resonance imaging (MRI) to determine the safety of posterior portals in posterior ankle arthroscopy. METHODS: Forty ankles from 38 patients who had undergone MRI scanning for ankle disorders were assessed (18 males, 20 females). For each ankle, the angles of the presumed position of the portals to the posterior neurovascular structures and the malleoli were measured on 4-mm proximal slices from the anterior tip of the fibula. The shortest distance from the sural nerve and the tibialis posterior neurovascular bundle to the position of the posterior portals was measured. RESULTS: The average distance between the posteromedial portal and the tibialis posterior neurovascular bundle was 18 ± 3 mm, whereas the average distance between the posterolateral portal and the sural nerve was 15 ± 3 mm. In 100% of ankles, there were no neurovascular structures lying within the region between the anterior tip of fibula and the posteromedial portal or between the posterior tip of fibula and the posteromedial portal. In 32 ankles (80%), the medial neurovascular structures were present on the medial side of the line running between the anterior tip of medial malleolus and the posteromedial portal. CONCLUSION: The posterior neurovascular structures were not in immediate proximity to where we estimated the posteromedial and posterolateral portals to be located. CLINICAL RELEVANCE: The findings of the present MRI-based study suggest that arthroscopic instruments oriented toward the fibula may be safely introduced into the posterior ankle without injuring the neurovascular structures.


Subject(s)
Ankle Injuries/surgery , Arthroscopy/instrumentation , Magnetic Resonance Imaging/methods , Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Retrospective Studies , Treatment Outcome
6.
Am J Sports Med ; 41(3): 528-34, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23348075

ABSTRACT

BACKGROUND: The defect size of an osteochondral lesion of the talus is one of the most important prognostic factors for deciding clinical outcomes. However, the prognostic factors for small osteochondral lesions of the talus are unknown. PURPOSE: To investigate the significant prognostic factors for small osteochondral lesions of the talus using arthroscopic bone marrow stimulation techniques. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Fifty ankles in 50 patients treated with arthroscopic bone marrow stimulation techniques for an osteochondral lesion of the talus (<150 mm(2)) were evaluated for prognostic factors. The patients were 22 men and 28 women (mean age, 35.0 years). Outcomes were measured using the American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot Scale, Berndt and Harty scale, and Saxena criteria. RESULTS: The mean lesion size was 62 mm(2) (range, 7-119 mm(2)). The mean AOFAS score improved from 74 (range, 18-90) preoperatively to 90 (range, 67-100) postoperatively. The Saxena criteria results were excellent, good, fair, and poor in 36 (72%), 8 (16%), 5 (10%), and 1 (2%) patients, respectively. The Berndt and Harty scale results were good in 34 (68%), fair in 6 (12%), and poor in 10 (20%) patients. Linear regression analyses showed prognostic significance for lesion depth and outcome. Medial lesions had a significantly higher incidence of poor outcomes than lateral lesions (P < .05). Among the medial lesions, lesions uncovered with the medial malleolus had inferior outcomes compared with covered lesions (P < .0001). There was no association between clinical outcome and lesion size or body mass index. In older patients (≥40 years), there was a significant trend toward inferior clinical outcomes (P < .05). CONCLUSION: Arthroscopic bone marrow stimulation techniques provided satisfactory clinical outcomes. However, older patients, deep lesions, and medial lesions uncovered with the medial malleolus were associated with inferior clinical outcomes.


Subject(s)
Arthroplasty, Subchondral , Arthroscopy , Cartilage, Articular/surgery , Curettage , Talus/surgery , Adolescent , Adult , Age Factors , Aged , Cartilage, Articular/injuries , Child , Female , Humans , Ligaments, Articular/injuries , Ligaments, Articular/surgery , Linear Models , Male , Middle Aged , Prognosis , Talus/injuries , Treatment Outcome , Young Adult
7.
Knee Surg Sports Traumatol Arthrosc ; 21(6): 1418-26, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23328985

ABSTRACT

PURPOSE: This study aimed to investigate the relationship between clinical outcomes, patient demographics and the 3D-geometric profiles of the osteochondral lesion of the talus (OLT) following arthroscopic debridement and bone marrow stimulation. METHODS: Between 2005 and 2011, arthroscopic debridement and bone marrow stimulation were performed on 50 ankles with OLT mean age of 36.0 (19.1) years and mean follow-up time of 35.5 (20.2) months. Clinical data were assessed using validated Japanese Society of Surgery of the Foot scoring. An outcome was deemed unsatisfactory if the JSSF score was less than 80. Magnetic resonance imaging and X-rays were used to assess the 3D-geometric profiles of the OLT. RESULTS: The mean preoperative and postoperative scores were 73.4 (13.6) and 89.6 (11.5), respectively (p < 0.001). Unsatisfactory outcomes were identified in 12 % of patients. Linear regression analyses showed that lesion depth and patient age were significantly negatively correlated with postoperative scores (p < 0.001). High prognostic significances were attributed to defect depth and age of patient, and cut-off values of 7.8 mm and 80 years, respectively, were recommended to avoid a postoperative score less than 80. No significant correlations between poor clinical outcome and the other lesion profiles or demographic factors were identified. CONCLUSION: Using 3D-geometric and demographic profiles, defect depth and age of patient are essential prognostic factors in OLT and may act as a basis for preoperative surgical decisions. A lesion depth ≥ 7.8 mm and age ≥ 80 years predict an unsatisfactory outcome following arthroscopic debridement and bone marrow stimulation.


Subject(s)
Bone Diseases/diagnosis , Cartilage Diseases/diagnosis , Cartilage, Articular/surgery , Talus/surgery , Adolescent , Adult , Aged , Arthroplasty, Subchondral , Arthroscopy , Bone Diseases/surgery , Cartilage Diseases/surgery , Debridement , Female , Humans , Male , Middle Aged , Young Adult
8.
Arch Orthop Trauma Surg ; 133(3): 321-31, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23224562

ABSTRACT

PURPOSES: To date, actual results of a minimally invasive distal linear metatarsal osteotomy (DLMO) via more explicit radiographic delineation are poorly understood and radiographic findings and clinical results have not been systematically correlated. Purposes of this study were (1) to evaluate the effectiveness of DLMO using a precise radiographic mapping system; and (2) to determine the relationship between radiographic outcomes and clinical results. MATERIALS AND METHODS: In 2008-2011, DLMO was performed in 30 patients (36 feet) who had reducible symptomatic hallux valgus. Clinical data were assessed using American Orthopaedic Foot and Ankle Society (AOFAS) score. Radiographs were reviewed at preoperative and final follow-up for delineations of first ray construct, hallux valgus angle (HVA), intermetatarsal angle (IMA), distal metatarsal articular angle, and other radiographic profiles. Correlation between postoperative AOFAS score and degree of malalignment was also analyzed. RESULTS: A total of 36 feet had predominantly moderate hallux valgus (26 feet with HVA: 21-39°; 23 feet with IMA: 12-17°). Mean preoperative and postoperative AOFAS scores were 70.2 ± 11.3 and 95 ± 6.4, respectively (p < 0.001). Mapping system revealed improvements of first ray construct deformity (p < 0.05). Significant reductions in all angular measurements were observed at final follow-up period (p < 0.001) and correlated significantly with changes in AOFAS score (p < 0.001). Nine feet (25 %) were observed with recurrence of deformity which showed HVA >15°. Significant sesamoid lateralization was observed (p < 0.05). Twenty-four feet (66.7 %) showing overall sagittal malunions were found with significant plantar angulation (p = 0.026) and non-significant plantar displacement compared with preoperative reference (p = 0.43). These radiographic abnormalities were not related to clinical outcomes including postoperative AOFAS scores (p > 0.05). CONCLUSION: DLMO is an acceptable procedure to correct reducible hallux valgus in most patients with moderate level of severity. Sagittal malunion, recurrence, and sesamoid lateralization are possibly radiographic abnormalities but are not associated with clinical impairments.


Subject(s)
Hallux Valgus/diagnostic imaging , Hallux Valgus/surgery , Metatarsal Bones/diagnostic imaging , Metatarsal Bones/surgery , Adolescent , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Minimally Invasive Surgical Procedures , Osteotomy , Radiography , Treatment Outcome , Young Adult
9.
Arthroscopy ; 28(12): 1882-8, 2012 Dec.
Article in English | MEDLINE | ID: mdl-23089350

ABSTRACT

PURPOSE: This study aimed to investigate the factors that influence the time to union after arthroscopic ankle arthrodesis. METHODS: From June 2005 to October 2010, 46 patients (50 ankles) underwent arthroscopic ankle arthrodesis with 6.0-mm cannulated cancellous screws. There were 22 men and 24 women (mean age, 63 years). Medical records and radiographs were retrospectively reviewed. Screw configurations used were as follows: 3 transmedial and translateral malleolar screws (ML3) in 12 ankles (24%), 2 transmedial and translateral malleolar screws (ML2) in 4 ankles (8%), 3 transmedial malleolar screws (M3) in 23 ankles (46%), and 2 transmedial malleolar screws (M2) in 11 ankles (22%). RESULTS: Radiographic fusion was achieved in 46 (92%) of the 50 ankles. The mean time to fusion was 11.0 ± 4.5 weeks for ML3, 13.1 ± 3.3 weeks for ML2, 9.7 ± 2.7 weeks for M3, and 12.5 ± 3.5 weeks for M2 (P < .05). The mean American Orthopaedic Foot & Ankle Society scores were 81.3 ± 2.2 for ML3, 83.5 ± 4.4 for ML2, 88.3 ± 1.5 for M3, and 85.3 ± 2.2 for M2. The mean time until radiographic fusion was 10.2 ± 3.4 weeks for correction angles of less than 10° and 13.2 ± 3.4 weeks for angles of 10° or greater (P < .01). In obese patients a significant difference in ankle fusion time was observed (12.6 ± 3.5 weeks for patients with body mass index ≥25 v 9.4 ± 2.9 weeks for patients with body mass index <25, P < .01). CONCLUSIONS: Overall, this study showed that arthroscopic ankle arthrodesis achieves a high rate of union, with fastest union achieved with 3 parallel screws placed medially from the distal tibia into the talus. Care should be taken when one is designing treatment strategies for obese patients and/or patients with large correction angles. LEVEL OF EVIDENCE: Level IV, retrospective case series.


Subject(s)
Ankle Joint/surgery , Arthrodesis/instrumentation , Bone Screws , Wound Healing/physiology , Adult , Aged , Aged, 80 and over , Ankle Joint/diagnostic imaging , Arthrodesis/methods , Arthroscopy , Body Mass Index , Female , Humans , Male , Middle Aged , Obesity/physiopathology , Radiography , Retrospective Studies , Time Factors
10.
Foot Ankle Surg ; 16(4): e88-90, 2010 Dec.
Article in English | MEDLINE | ID: mdl-21047598

ABSTRACT

Osteonecrosis is a serious complication of acute lymphoblastic leukemia (ALL) therapy. The spontaneous regression or healing of osteonecrosis is rare. An unusual case of an osteochondral defect of the talus secondary to osteonecrosis is herein presented. We treated a 26-year-old female who presented with an osteochondral defect of the talus after necrosis. ALL had previously been diagnosed in 1994 and the patients had been treated with chemotherapy included corticosteroid. She was thereafter diagnosed to have bilateral osteonecrosis of the talus in 1996, and thus had been treated with weight-bearing restriction using a patellar tendon bearing brace. She felt pain in her right ankle in 2006. Magnetic resonance imaging (MRI) showed an osteochondral defect in the lateral aspect of the talus and normal bone marrow signal in the right ankle. We performed arthroscopic treatment by means of a bone marrow stimulation technique. At second-look arthroscopy, the aspect of the talus was completely covered by fibrocartilage like tissue. This procedure is therefore considered to be one option for the treatment of an osteochondral defect of the talus after necrosis in young patients.


Subject(s)
Arthroscopy , Cartilage/surgery , Osteonecrosis/chemically induced , Osteonecrosis/surgery , Talus/surgery , Adrenal Cortex Hormones/adverse effects , Adult , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Bone Marrow/physiology , Cartilage/pathology , Female , Humans , Magnetic Resonance Imaging , Precursor Cell Lymphoblastic Leukemia-Lymphoma/drug therapy , Talus/pathology , Wound Healing
11.
J Orthop Sci ; 13(1): 3-6, 2008 Jan.
Article in English | MEDLINE | ID: mdl-18274848

ABSTRACT

BACKGROUND: A Maisonneuve fracture consists of a proximal fibular fracture with associated syndesmotic ligament disruption and injury to the medial ankle structures. The treatment outcome is good in most cases, although poor results have also been reported. The purpose of this study was to investigate intra-articular lesions in Maisonneuve fractures. METHODS: The subjects consisted of four patients (four ankle joints) who had suffered a Maisonneuve fracture and had undergone surgical treatment between June 2005 and November 2005. The mean age was 24. 2 years. At the time of surgery, we performed ankle arthroscopy and determined the presence of tibiofibular syndesmosis disruption, cartilaginous damage, and ligament damage. Lesions of the articular cartilage were graded by depth as determined by inspection and probing. RESULTS: All four of the cases had cartilaginous damage to the medial section of the talar dome. Lateral lesions were not observed. Chondral debris and hemarthrosis were noted in virtually all cases, and each ankle had a tear on the anterior inferior tibiofibular ligament and interosseous tibiofibular ligament. No patients had a tear of the posterior inferior tibiofibular ligament. CONCLUSIONS: Arthroscopy was useful in identifying associated intra-articular lesions in Maisonneuve fractures.


Subject(s)
Ankle Injuries/pathology , Arthroscopy , Fibula/injuries , Fractures, Bone/pathology , Fractures, Bone/surgery , Ligaments, Articular/injuries , Adult , Ankle Injuries/complications , Ankle Injuries/surgery , Cohort Studies , Fractures, Bone/complications , Humans , Male , Range of Motion, Articular , Recovery of Function , Treatment Outcome
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