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Journal of Bone and Joint Surgery, American Volume | 2009

Postoperative Incomplete Reduction of the Sesamoids as a Risk Factor for Recurrence of Hallux Valgus

Ryuzo Okuda; Mitsuo Kinoshita; Toshito Yasuda; Tsuyoshi Jotoku; Naoshi Kitano; Hiroaki Shima

BACKGROUND It is unknown whether postoperative incomplete reduction of the sesamoids is a risk factor for the recurrence of hallux valgus. The purpose of the present study was to clarify the relationship between the postoperative relative sesamoid position and the recurrence of hallux valgus. METHODS Dorsoplantar weight-bearing radiographs of sixty normal feet (the control group) and sixty-five feet with hallux valgus (the hallux valgus group) in a study of adult women were reviewed. The feet in the hallux valgus group were treated with a proximal metatarsal osteotomy, and the radiographs were assessed preoperatively, at the early follow-up interval (at a mean of 3.1 months), and at the most recent follow-up interval (at a mean of forty-five months). The position of the medial sesamoid was classified with a grading system ranging from I through VII as described by Hardy and Clapham. In the feet with hallux valgus, we defined a grade of IV or less as the normal position of the medial sesamoid (the normal-position group) and grade V or greater as lateral displacement of the sesamoid (the displacement group). RESULTS Fifty feet (83%) in the control group were classified as grade IV or less and ten, as grade V. All feet in the hallux valgus group were classified as grade V or greater preoperatively, forty-eight feet (74%) were classified as grade IV or less at the early follow-up evaluation, and forty-two feet (65%) were classified as grade IV or less at the most recent follow-up evaluation. The average hallux valgus angle in the hallux valgus group was 38.3 degrees (range, 25 degrees to 60 degrees ) preoperatively, 11.9 degrees (range, 4 degrees to 28 degrees ) at the time of the early follow-up, and 13.9 degrees (range, 0 degrees to 33 degrees ) at the time of the most recent follow-up. There was no significant difference in the average hallux valgus angle between the early and most recent follow-up evaluations in the feet that were considered to be in the normal-position group at the time of the early follow-up (p = 0.084). In the feet that were considered to be in the displacement group at the time of the early follow-up, the average hallux valgus angle at the time of the most recent follow-up was significantly greater than that at the time of the early follow-up (19.5 degrees +/- 8.4 degrees compared with 15.0 degrees +/- 5.8 degrees ) (p = 0.0082). The feet that were in the displacement group at the time of the early follow-up had a greater risk of having recurrence of the hallux valgus at that time than did those in the normal-position group (odds ratio, 10.0; 95% confidence interval, 2.75 to 36.33). CONCLUSIONS Postoperative incomplete reduction of the sesamoids can be a risk factor for the recurrence of hallux valgus. The identification of incomplete reduction of the sesamoids intraoperatively may allow modification of surgical procedures and improvement of the surgical results.


Journal of Bone and Joint Surgery, American Volume | 2001

The dorsiflexion-eversion test for diagnosis of tarsal tunnel syndrome

Mitsuo Kinoshita; Ryuzo Okuda; Junichi Morikawa; Tsuyoshi Jotoku; Muneaki Abe

Background: The clinical diagnosis of tarsal tunnel syndrome lacks objectivity and consistency. We have devised a new diagnostic physical examination test in which the tibial nerve is compressed as it runs beneath the flexor retinaculum behind the medial malleolus. In this test, the ankle is passively maximally everted and dorsiflexed while all of the metatarsophalangeal joints are maximally dorsiflexed and held in this position for five to ten seconds. Methods: We performed this test on fifty normal volunteers (100 feet) and on thirty-seven patients (forty-four feet) treated operatively for tarsal tunnel syndrome between 1987 and 1997. We performed the maneuver both preoperatively and postoperatively and recorded any consequent changes in the signs and symptoms; during the operation we observed the altered anatomical relationships in the tarsal tunnel that were produced by the maneuver. The average duration of follow-up was three years and eleven months. Results: Before the operation, the signs and symptoms of tarsal tunnel syndrome were intensified or induced by the maneuver in fifteen of the twenty feet of the patients who reported numbness, in fifteen of the seventeen feet of those who reported pain alone, and in six of the seven feet of those who had combined numbness and pain. Local tenderness was intensified in forty-two of forty-three feet, and it was induced in one foot in which it had been previously absent. A Tinel sign became more pronounced in forty-one feet, and the sign was induced in three feet in which it had been absent previously. During the operation, the tibial nerve was stretched and compressed beneath the laciniate ligament when the ankle was dorsiflexed, the heel was everted, and the toes were dorsiflexed. Preoperative signs and symptoms disappeared on an average of 2.9 months after the operation, and they could not be induced by repeating the test except in three patients, all of whom had tarsal tunnel syndrome subsequent to a fracture of the calcaneus. In the normal volunteers, no symptoms or signs could be induced by the test. Conclusion: This new physical examination test is effective in facilitating the diagnosis of tarsal tunnel syndrome.


American Journal of Sports Medicine | 2005

Arthroscopic findings in chronic lateral ankle instability: do focal chondral lesions influence the results of ligament reconstruction?

Ryuzo Okuda; Mitsuo Kinoshita; Junichi Morikawa; Toshito Yasuda; Muneaki Abe

Background There are few studies that have assessed the influence of focal chondral lesions on the results of ligament reconstruction for chronic lateral ankle instability. Hypothesis Focal chondral lesions do not influence the results of ligament reconstruction. Study Design Case series; Level of evidence, 4. Methods Arthroscopic examination of the ankle was performed on 30 consecutive patients immediately before ligament reconstruction using the palmaris longus tendon. Clinical assessment was performed using the Karlsson scoring scale. A radiologic assessment was performed on stress radiographs of the ankle. Preoperative anteroposterior and lateral weightbearing radiographs of the ankle did not show any joint space narrowing in any ankle. The mean duration of follow-up was 38 months. Results On arthroscopy, focal chondral lesions were found in 19 ankles (63%). Chondral lesions were located on the medial side of the tibial plafond in 13 ankles (43%), on the lateral side in 2 ankles (7%), on the lateral side of the talar dome in 3 ankles (10%), and on the medial side in 9 ankles (30%). Postoperative mean Karlsson scores in patients without chondral lesions and in those with chondral lesions were 99.1 and 98.4 points, respectively. Postoperative mean talar tilt angles in patients without chondral lesions and in those with chondral lesions were 5.9° and 4.7°, respectively. There were no significant differences in the clinical and radiologic results between patients with chondral lesions and those without chondral lesions. Conclusions Reconstruction of the lateral ligament can be successful regardless of the presence of focal chondral lesions in patients with chronic lateral ankle instability when preoperative weightbearing radiographs of the ankle do not show any joint space narrowing.


Journal of Bone and Joint Surgery, American Volume | 2007

The Shape of the Lateral Edge of the First Metatarsal Head as a Risk Factor for Recurrence of Hallux Valgus

Ryuzo Okuda; Mitsuo Kinoshita; Toshito Yasuda; Tsuyoshi Jotoku; Naoshi Kitano; Hiroaki Shima

BACKGROUND The relationship between the shape of the first metatarsal head and hallux valgus deformity remains controversial. The purpose of the present study was to retrospectively analyze differences in the radiographic appearance of the shape of the lateral edge of the first metatarsal head between women with normal feet and those with hallux valgus and to clarify the relationship between the shape of the lateral edge and the postoperative recurrence of hallux valgus deformity. METHODS Dorsoplantar weight-bearing radiographs of sixty normal feet in women (the control group) and sixty feet in women with hallux valgus (the hallux valgus group) were reviewed. The feet in the hallux valgus group were treated with a proximal metatarsal osteotomy, and the radiographs of those feet were assessed preoperatively, at the time of early follow-up (mean, 3.4 months), and at the time of the most recent follow-up (mean, forty-eight months). The shape of the lateral edge, which was defined as consisting of the articular and lateral surfaces of the first metatarsal head, was examined. The shape of the lateral edge was classified as one of three types: round (type R), angular (type A), and intermediate (type I). We defined the round sign as being positive when the shape of the lateral edge was classified as type R. RESULTS Prior to surgery, the prevalence of the type-R shape was significantly greater in the hallux valgus group than it was in the control group (78.3% compared with 1.7%; p < 0.0001) and the prevalence of type-A shape was significantly lower in the hallux valgus group than in the control group (3.3% compared with 81.7%; p < 0.0001). In the hallux valgus group, the prevalence of the type-R shape at the time of the early follow-up after surgery was significantly lower than that before surgery (p < 0.0001). Feet with a positive round sign at the time of the early follow-up had a greater risk of having recurrence of the hallux valgus deformity at the time of the most recent follow-up than did those without a round sign at the time of the early follow-up (odds ratio, 12.71; 95% confidence interval, 3.21 to 50.36). CONCLUSIONS There is a significant relationship between a round-shaped lateral edge of the first metatarsal head and hallux valgus, and a positive round sign after a proximal first metatarsal osteotomy can be a risk factor for the recurrence of hallux valgus.


Foot & Ankle International | 2003

Tarsal tunnel syndrome associated with an accessory muscle.

Mitsuo Kinoshita; Ryuzo Okuda; Junichi Morikawa; Muneaki Abe

Between 1986 and 1999, we surgically treated 41 patients (49 feet) with Tarsal Tunnel Syndrome (TTS) in whom seven (eight feet) were associated with an accessory muscle. An accessory flexor digitorum longus muscle was present in six patients, and an accessory soleus muscle was in one patient (both feet). Three of them were males and four females, with the mean age of 33.1 years (12 to 59 years). The mean interval from the onset of symptoms to operation was 7.5 months (range, six to nine months). All patients with an accessory muscle had a history of trauma or strenuous sporting activity. The diagnosis of TTS was made based on physical findings in all the patients (eight feet) and confirmed in five patients (six feet) by electrophysiological examination. Imaging examinations (radiography, ultrasonography, MRI) revealed abnormal bone and soft tissue lesions in and around the tarsal tunnel. Preoperative signs and symptoms disappeared average 4.1 months after decompression of the tibial nerve in addition to excision of the muscle. No functional deficit was observed at final follow-up (24 to 88 months).


Journal of Bone and Joint Surgery, American Volume | 2009

Radiographic measurements in patients with hallux valgus before and after proximal crescentic osteotomy.

Hiroaki Shima; Ryuzo Okuda; Toshito Yasuda; Tsuyoshi Jotoku; Naoshi Kitano; Mitsuo Kinoshita

BACKGROUND Radiographic measurements such as those of the hallux valgus angle and the intermetatarsal angle are essential parameters for assessing the severity of hallux valgus deformities and the extent of surgical correction required. However, to our knowledge, no study has investigated the reliability of the measurements that are made radiographically before and after a proximal crescentic osteotomy of the first metatarsal. The purpose of the present study was to investigate the intraobserver and interobserver reliability of different methods that are used to measure the angles and to determine the most reliable method. METHODS We selected twenty preoperative and twenty postoperative dorsoplantar weight-bearing radiographs for patients who had undergone a proximal crescentic osteotomy of the first metatarsal. Three foot and ankle surgeons measured the hallux valgus angle and the intermetatarsal angle with use of five different methods. We calculated the intraobserver and interobserver correlation coefficients and agreement to determine the most reliable method. RESULTS Significant differences were observed among the methods with regard to the postoperative hallux valgus angle (p < 0.05) and the preoperative and postoperative intermetatarsal angles (p < 0.01 for both). The method in which a line connecting the centers of the first metatarsal head and the proximal articular surface of the first metatarsal was used to define the longitudinal axis of the first metatarsal yielded the highest intraobserver and interobserver correlation coefficients for the preoperative hallux valgus and intermetatarsal angles and the postoperative hallux valgus angle. For this method alone, the intraobserver and interobserver agreements for the angular measurements were found to be >80%. CONCLUSIONS A line connecting the centers of the first metatarsal head and the proximal articular surface of the first metatarsal to define its longitudinal axis yields the best intraobserver and interobserver reliability for the measurement of the hallux valgus and intermetatarsal angles. Therefore, this method can be recommended for evaluating radiographs before and after a proximal crescentic osteotomy performed for the treatment of hallux valgus.


American Journal of Sports Medicine | 2006

Tarsal Tunnel Syndrome in Athletes

Mitsuo Kinoshita; Ryuzo Okuda; Toshito Yasuda; Muneaki Abe

Background The details of the occurrence of tarsal tunnel syndrome in athletes have not been well documented in the literature, and more data on tarsal tunnel syndrome related to sporting activity are necessary to enable better recognition of this condition. Hypothesis Sporting activities make athletes vulnerable to the occurrence of tarsal tunnel syndrome under specific conditions. Study Design Case series; Level of evidence, 4. Methods Between 1986 and 2002, 18 patients with tarsal tunnel syndrome related to sporting activities were surgically treated, of whom 15 patients (21 feet; mean age, 17.8 years) were competitive athletes and 3 were recreational sports amateurs (4 feet; mean age, 52.7 years). To assess the role of physical factors and sporting activities in making athletes vulnerable to the occurrence of tarsal tunnel syndrome, the authors reviewed the medical charts and evaluated the results of treatment. The mean duration of follow-up was 58.6 months. Results Activities that triggered tarsal tunnel syndrome were those that applied a heavy burden on the ankle joint such as sprinting, jumping, and performing ashibarai in judo under specific physical conditions. Predisposing underlying physical factors were flatfoot deformity and an existence of talocalcaneal coalition, accessory muscles, and bony fragments around the tarsal tunnel. The majority of patients were able to return to the same sport after treatment. Conclusion Tarsal tunnel syndrome occurs in athletes involved in strenuous sporting activities, especially when predisposing physical factors are present.


Clinical Orthopaedics and Related Research | 2000

Distal soft tissue procedure and proximal metatarsal osteotomy in hallux valgus.

Ryuzo Okuda; Mitsuo Kinoshita; Junichi Morikawa; Tsuyoshi Jotoku; Muneaki Abe

The results of a distal soft tissue procedure and a proximal metatarsal osteotomy in patients with symptomatic hallux valgus deformity were reviewed. The series consisted of 33 patients (47 feet; mean age of patients, 44 years). The average followup period was 48 months. At followup, 41 feet (29 patients, 85%) were free from pain at the first metatarsophalangeal joint. In six feet (four patients), the pain was improved but persisted. The mean hallux valgus angle was 38° before surgery and 13.8° after surgery. The mean intermetatarsal angle was 17.7° before surgery and 7° after surgery. The postoperative hallux valgus angle and intermetatarsal angle in patients who had pain at the first metatarsophalangeal joint after surgery were greater than those in patients without pain after surgery. This procedure corrects the hallux valgus deformity and relieves the symptoms, but careful attention should be paid to the surgical technique to obtain consistent and satisfactory results.


Foot & Ankle International | 1999

Reconstruction for chronic lateral ankle instability using the palmaris longus tendon: is reconstruction of the calcaneofibular ligament necessary?

Ryuzo Okuda; Mitsuo Kinoshita; Junichi Morikawa; Tsuyoshi Jotoku; Muneaki Abe

The palmaris longus tendon was used to reconstruct the anterior talofibular ligament (ATFL) in 27 ankles with chronic lateral instability. The mean age of the patients at surgery was 23 years, and the follow-up was more than 2 years. The functional evaluation showed excellent or good results in all ankles. Twenty-seven ankles were divided into two groups according to operative findings: group A consisted of 11 ankles with old isolated injury of the ATFL, and group B consisted of 16 ankles with old combined injuries of the ATFL and the calcaneofibular ligament. There were no significant differences in clinical results between group A and group B. The preoperative mean talar tilt angles on stress radiograph in group B were significantly larger than those in group A. At follow-up, there were no significant differences in the mean talar tilt angles between group A and group B. We demonstrate that reconstruction of the calcaneofibular ligament along with the ATFL is not necessary for patients with chronic combined lateral ligament instability.


Foot & Ankle International | 2008

Proximal Metatarsal Osteotomy for Hallux Valgus: Comparison of Outcome for Moderate and Severe Deformities

Ryuzo Okuda; Mitsuo Kinoshita; Toshito Yasuda; Tsuyoshi Jotoku; Hiroaki Shima

Background: We compared the results of a distal soft-tissue procedure with a proximal crescentic osteotomy of the first metatarsal for moderate and severe hallux valgus. Materials and Methods: The series consisted of 54 feet treated with this procedure. The average followup was 30 months. Fifty-four feet were divided into two groups including Group M (moderate) (24 feet, preoperative hallux valgus angle of 40 degrees or less and preoperative intermetatarsal angle of less than 18 degrees) and Group S (severe) (30 feet, preoperative hallux valgus angle of greater than 40 degrees or preoperative intermetatarsal angle of 18 degrees or greater). Results: The difference between Group M and S was not significant with regard to the age of patients, duration of followup, or postoperative pain and function scores on the American Orthopaedic Foot and Ankle Society scale. However, postoperative alignment score in Group M was significantly greater than that in Group S (p = 0.038). Postoperative hallux valgus and intermetatarsal angles in Group S were significantly greater than those in Group M, respectively (p = 0.025, p = 0.001). The prevalence of recurrent hallux valgus (hallux valgus angle of 20 degrees or greater) in Group S was significantly higher than that in Group M (p = 0.013). Conclusion: This procedure is an effective method for relieving pain and improving function regardless of the severity of hallux valgus. However, the correction of moderate hallux valgus is likely to be better than that of severe hallux valgus.

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Hisateru Niki

St. Marianna University School of Medicine

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Shinobu Tatsunami

St. Marianna University School of Medicine

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