Kazuki Kanazawa
Fukuoka University
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Featured researches published by Kazuki Kanazawa.
American Journal of Sports Medicine | 2013
Ichiro Yoshimura; Kazuki Kanazawa; Akinori Takeyama; Chayanin Angthong; Takahiro Ida; Tomonobu Hagio; Hirofumi Hanada; Masatoshi Naito
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 mm2) 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 mm2 (range, 7-119 mm2). 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.
Arthroscopy | 2012
Ichiro Yoshimura; Kazuki Kanazawa; Akinori Takeyama; Takahiro Ida; Tomonobu Hagio; Chayanin Angthong; Masatoshi Naito
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.
Journal of Orthopaedic Science | 2008
Ichiro Yoshimura; Masatoshi Naito; Kazuki Kanazawa; Akinori Takeyama; Takahiro Ida
BackgroundA 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.MethodsThe 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.ResultsAll 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.ConclusionsArthroscopy was useful in identifying associated intra-articular lesions in Maisonneuve fractures.
Journal of Foot & Ankle Surgery | 2012
Daisuke Noda; Ichiro Yoshimura; Kazuki Kanazawa; Tomonobu Hagio; Masatoshi Naito
It is well known that rupture of the flexor hallucis longus tendon can be associated with open injuries and that closed rupture of the flexor hallucis longus tendon is rare. Tendon injuries of the foot can occur secondary to direct, indirect, or repetitive injury. Repetitive tendon injuries can cause tendinitis or stenosing tenosynovitis. Tendinitis is associated with internal tendon injury that can present with tendon thickening, mucinoid degeneration, nodule development, or in situ partial tears. Stenosing tenosynovitis is the development of tendon adhesions within the tendon sheath that interfere with tendon gliding, known as trigger toe. The flexor hallucis longus tendon is susceptible to injury along its entire course. A total of 35 cases of complete or partial closed ruptures of the flexor hallucis longus tendon have been reported. We present the case of complete subcutaneous rupture of the flexor hallucis longus tendon associated with trauma at the proximal phalangeal head.
Foot & Ankle International | 2013
Ichiro Yoshimura; Masatoshi Naito; Kazuki Kanazawa; Takahiro Ida; Kunihide Muraoka; Tomonobu Hagio
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.
Journal of Foot & Ankle Surgery | 2015
Ichiro Yoshimura; Ryuji Ichimura; Kazuki Kanazawa; Takahiro Ida; Tomonobu Hagio; Hirotaka Karashima; Masatoshi Naito
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 workers 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.
Journal of Foot & Ankle Surgery | 2013
Kazuki Kanazawa; Ichiro Yoshimura; Teruaki Shiokawa; Tomonobu Hagio; Masatoshi Naito
We surgically treated an osteochondral lesion associated with a stress fracture of the tarsal navicular. The surgical procedure involved the confirmation and complete resection of the lesion under direct vision, followed by the transplantation of block-shaped iliac bone grafts. The postoperative computed tomography scan showed that the lesions had disappeared, the grafted bone had fused, and the stress fracture had healed. However, the tarsal navicular joint surface was slightly irregular. The patient was able to resume her sports activities 15 weeks after surgery. We have described a novel method to reconstruct the tarsal navicular after osteochondral lesion resection.
Foot and Ankle Surgery | 2010
Ichiro Yoshimura; Masatoshi Naito; Kazuki Kanazawa; Akinori Takeyama; Hirotaka Karashima; Takahiro Ida; Tomohiro Nomura
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.
Journal of the American Podiatric Medical Association | 2016
Terufumi Shibata; Ichiro Yoshimura; Kazuki Kanazawa; Tomonobu Hagio; So Minokawa; Masaya Nagatomo; Masatoshi Naito
Mortons neuroma is a common condition that mainly affects middle-aged women, and many articles have addressed the surgical treatment of this condition. Previous reports have described bilateral neuroma excision in women but not in men. We report a rare case of bilateral neuromas in a male patient treated with simultaneous neurectomy.
Foot & Ankle Orthopaedics | 2016
So Minokawa; Ichiro Yoshimura; Masatoshi Naito; Kazuki Kanazawa; Tomonobu Hagio
Category: Hindfoot Introduction/Purpose: Distal first metatarsal osteotomies are recommended for surgical treatment of mild to severe hallux valgus (HV) deformities. Angthong et al. reported that minimally invasive distal linear metatarsal osteotomy (DLMO) exhibited good outcomes, with no major complications. However, avascular necrosis of the metatarsal head following a distal osteotomy has been reported, because an aggressive plantar cut can disrupt the soft tissue plantarly, thereby disrupting the blood supply of digital arteries. The purpose of this study was to evaluate the in vivo blood flow of the pre- and post-osterotomy metatarsal head in patients with HV using laser Doppler flowmetry (LDF). Methods: Between April and November 2015, DLMO was performed on seven patients with HV. The patients comprised one male and four females, with a mean age at surgery of 43.4 (21–62) years. The primary surgical indications for DLMO were all levels of severity of possible manual correction in patients with foot pain. The patients were placed in the supine position, and without a tourniquet, a 1.5-cm skin incision was centered over the medial aspect of the first metatarsal neck. A 2.0-mm Kirschner wire was inserted manually from the wound to the medial side of the hallux using a retrograde technique. Under direct vision, the Kirschner wire was introduced into the medullary canal of the first metatarsal shaft. Blood flow measurements of the pre- and post-osteotomy first metatarsal head in the seven patients were performed by LDF (ALF21 N; ADVANCE Co., Tokyo, Japan). The probe was touched to the first metatarsal head. The blood flow measurements were repeated three times, and the mean values were calculated. Results: On preoperative plain radiographs, the mean hallux valgus angle was 38.0° (range: 22.4–45.8°), and the mean intermetatarsal angle was 17.0° (range: 10.4–21.9°). The mean pre- and post-DLMO systolic blood pressure at the time of the measurements was 87.3±7.76 and 88.1±8.25 mmHg, respectively (P=0.85). The mean pre- and post-DLMO blood flow rate was 1.71±0.68 and 1.66±0.49 ml/min/100 g, respectively (P=0.90). Conclusion: Steven et al. reported that a distal osteotomy can lead to avascular necrosis of the metatarsal head, because an aggressive plantar cut can disrupt the soft tissue plantarly, thereby disrupting the blood supply of digital arteries. However, we found that blood flow of the pre- and post-osteotomy metatarsal head was present in all patients examined, with no significant difference in the blood flow rates of the metatarsal head before and after DLMO. Based on the present results, it is possible to avoid major complications, such as avascular necrosis of the metatarsal head, because DLMO is minimally invasive and involves less release of the soft tissue.