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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.


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.


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.


Acta Orthopaedica Scandinavica | 2000

Unfavorable effect of knee immobilization on Achilles tendon healing in rabbits.

Toshito Yasuda; Mitsuo Kinoshita; Muneaki Abe; Yuro Shibayama

This study was undertaken to assess the effect of knee immobilization on the treatment of Achilles tendon rupture. After their Achilles tendons were severed, rabbits were divided into 2 groups. In Group A, only the ankle joint was immobilized. In Group B, both the knee and ankle joints were immobilized. At 4 weeks after surgery, both the ultimate tensile force and stiffness of the severed tendons were significantly greater in Group A than in Group B. In Group A, dense collagen fibers were seen in the repaired tendons, and the bundles of collagen fibers were parallel to one another along the axis of the tendons. In contrast, in Group B, dilated veins and capillaries were seen in the repaired tendons, and the proliferation of connective tissue containing collagen fibers was severely reduced around these veins and capillaries and was in general irregular and uneven. These results suggest that knee immobilization retards the healing of a ruptured Achilles tendon without suture, due to congestion and tension deprivation produced by keeping the tendon static.


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.


Clinical Orthopaedics and Related Research | 2005

Proximal metatarsal osteotomy: relation between 1- to greater than 3-years results.

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

We analyzed the relationship between the 1-year and greater than 3-years results of a distal soft tissue procedure with a proximal osteotomy for hallux valgus in the same patient population. The series consisted of 55 feet treated with this procedure. The results at 1 year and greater than 3 years were evaluated. The final followup was greater than 3 years. Patients with pain in the first metatarsophalangeal joint at the 1-year followup had a greater risk of having pain at the final followup than did patients without pain at the 1-year followup. Patients with metatarsalgia at the 1-year followup had a greater risk of having metatarsalgia at the final followup than did patients without metatarsalgia at the 1-year followup. The extension of the first metatarsophalangeal joint at the final followup was greater than extension at the 1-year followup. In 48 feet (87%), radiologic evaluation showed no or minimal changes in the hallux valgus and intermetatarsal angles between 1 year and greater than 3 years followup. The data suggest the 1-year results predict those beyond 3 years, although the extension of the first metatarsophalangeal joint may increase 1 year after surgery. Level of Evidence: Prognostic study, Level III. See the Guidelines for Authors for a complete description of levels of evidence.


American Journal of Sports Medicine | 2007

Reconstruction of Chronic Achilles Tendon Rupture with the use of Interposed Tissue between the Stumps

Toshito Yasuda; Mitsuo Kinoshita; Ryuzo Okuda

Background The gap between the tendon stumps in chronic Achilles tendon rupture has reportedly been filled with interposed scar tissue. In the authors’ clinical experience, this interposed tissue is often thick and resists tension, so they considered it was possible to use the interposed tissue for reconstruction of Achilles tendon rupture. Hypothesis Scar tissue interposed between the tendon stumps has the capacity to form tendon-like repair tissue in patients with chronic Achilles tendon rupture. Study Design Case series; Level of evidence, 4. Methods Six patients with chronic rupture of the Achilles tendon underwent tendon reconstruction with the use of interposed tissue between the stumps. The average time from the primary injury to surgery was 22 weeks (range, 9 to 30 weeks). Preoperative magnetic resonance imaging (MRI), histology of the interposed tissue, and clinical results were evaluated. The average postoperative follow-up period was 31 months (range, 24 to 43 months). Results Preoperative T2-weighted MRI in all cases revealed that chronically ruptured Achilles tendons were thickened and fusiform-shaped with diffuse intratendinous high-signal alterations throughout. Longitudinal high-signal bands were seen throughout the tendon, except at the musculotendinous junction and insertion on the calcaneus. Histologically, scar tissue interposed between the tendon stumps consisted of dense collagen fibers, and degenerative changes were not seen. After surgery, no patient had difficulty in walking or stair climbing, and all were able to perform a single-limb toe raise. The mean preoperative and postoperative American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot scores were 88.2 and 98.3 points, respectively; the difference was statistically significant (P = .0277). Conclusion Interposed tissue between the tendon stumps is suitable for repair of chronic Achilles tendon rupture if preoperative MRI shows a thickened fusiform-shaped Achilles tendon with diffuse intratendinous high-signal alterations throughout.


Foot & Ankle International | 2015

Proximal Supination Osteotomy of the First Metatarsal for Hallux Valgus

Toshito Yasuda; Ryuzo Okuda; Tsuyoshi Jotoku; Hiroaki Shima; Takashi Hida; Masashi Neo

Background: Risk factors for hallux valgus recurrence include postoperative round-shaped lateral edge of the first metatarsal head and postoperative incomplete reduction of the sesamoids. To prevent the occurrence of such conditions, we developed a proximal supination osteotomy of the first metatarsal. Our aim was to describe this novel technique and report the outcomes in this report. Methods: Sixty-six patients (83 feet) underwent a distal soft tissue procedure combined with a proximal supination osteotomy. After the proximal crescentic osteotomy, the proximal fragment was pushed medially, and the distal fragment was abducted, and then the distal fragment of the first metatarsal was manually supinated. Outcomes were assessed using the American Orthopaedic Foot & Ankle Society (AOFAS) score and radiographic examinations. The average follow-up duration was 34 (range, 25 to 52) months. Results: The mean AOFAS score improved significantly from 58.0 points preoperatively to 93.8 points postoperatively (P < .0001). The mean hallux valgus and intermetatarsal angle decreased significantly from 38.6 and 18.0 degrees preoperatively to 11.0 and 7.9 degrees postoperatively, respectively (both, P < .0001). Sixty-nine feet (69/83, 83%) had a positive round sign preoperatively, and 66 feet (66/83, 80%) had a negative round sign postoperatively. According to the Hardy’s classification of position of the sesamoids, all feet were classified as grade V or greater preoperatively, and 49 feet (49/83, 59%) were classified as grade IV or less postoperatively. Three feet (3/83, 4%) had recurrence of hallux valgus, defined as a hallux valgus angle ≥ 25 degrees. Conclusion: The rates of occurrence of a positive round sign and incomplete reduction of the sesamoids significantly decreased postoperatively, which may have contributed to the low hallux valgus recurrence rates. We conclude that a proximal supination osteotomy was an effective procedure for correction of hallux valgus and can achieve a low rate of hallux valgus recurrence. Level of Evidence: Level IV, retrospective case series.

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K. Mori

Osaka Medical College

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