Comparison of symptomatic unstable ankle with and without os subfibulare.

BACKGROUND: This study aimed to compare the patients background, clinical scores, condition of the lateral ligament, mechanical instabilities, and chondral lesions in ankles with symptomatic os subfibulare compared to those in ankles with chronic lateral instability without os subfibulare. METHODS: Of the 212 ankles with a chronic lateral instability that were surgically treated, 72 ankles had an os subfibulare. All ankles were examined by arthroscopy during surgery. Age, sex, preoperative American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot Scale scores, remnant condition of the lateral ligaments, and chondral lesions were compared between ankles with symptomatic os subfibulare and ankles with chronic lateral instability without os subfibulare. RESULTS: There were no statistically significant differences between the groups in terms of the sex ratio (males: females, 35:37 vs. 53:87, n.s.) and the AOFAS Ankle-Hindfoot Scale scores (median; 75 vs. 77, n.s.). There were statistically significant differences in patient age (median: 20 vs. 24.5 years, p < 0.01), talar tilt angle (median: 9.0° vs 12.0°, p < 0.01), anterior drawer distance (6.2 vs. 7.0 mm, p < 0.01), chondral lesions (G0:G1:G2:G3, 35:21:66:5 vs. 40:44:27:29, p < 0.01), condition of the anterior talofibular ligament (intact: repairable remnant: poor remnant, 0:70:2 vs. 1:112:27, p < 0.01), and condition of the calcaneofibular ligament (intact: repairable remnant: poor remnant, 44:26:2 vs. 77:35:28, p < 0.01) between the groups. CONCLUSION: This study suggests that the condition of the lateral ligaments including mechanical instability and cartilage of the ankle were less severe in the ankles with symptomatic os subfibulare than in those with chronic lateral instability without os subfibulare. The patients' age was lower in the ankles with symptomatic os subfibulare than in those with chronic lateral instability without os subfibulare. The clinical scores and gender ratio were not statistically different between the group.

Accessory Anterolateral Talar Facet Syndrome After Treatment of Neglected Fracture of the Lateral Process of the Talus: A Case Report.

Fracture of the lateral process of the talus has often been missed or confused with lateral ankle sprain, and this can lead to long-term untreated cases of nonunion, malunion, and subtalar joint osteoarthritis. In a review of the published data, accessory anterolateral talar facet syndrome was not found after treatment of nonunion of the lateral process of the talus fracture. This report presents the case of a 40-year-old male snowboard instructor who suffered from a neglected fracture of the lateral process of the talus and was treated with open reduction using an iliac autogenous bone graft. Subsequently, partial resection of the anterior aspect of the process was required to treat the impingement syndrome that developed secondary to the united but enlarged lateral process. The patient resumed his activities a year after the second operation. We describe the consequences of misdiagnosis of the lateral process of the talus and its management.

Glomus Tumor in the Tarsal Tunnel: A Case Report.

Glomus tumors are painful benign neoplasms. They commonly present in the hand and are mostly solitary lesions. We report a rare case of multiple glomus tumors in the lower leg. Moreover, 1 of the tumors was in the tarsal tunnel. Resection of the tumors resulted in the early diagnosis of glomus tumors and complete symptom relief. Because of its rarity, diagnosing an extradigital glomus tumor is difficult. Recognition of glomus tumors allows for an early diagnosis and resection, and preoperative magnetic resonance imaging helps in the detection of multiple lesions. Before resection, we considered tarsal tunnel syndrome in the differential diagnosis because of the symptoms and location of the tumor. Tarsal tunnel syndrome is a comparatively well-known disease in the foot. When tarsal tunnel syndrome is suspected, a glomus tumor should also be considered in the differential diagnosis.

The short-term effect after a single injection of high-molecular-weight hyaluronic acid in patients with enthesopathies (lateral epicondylitis, patellar tendinopathy, insertional Achilles tendinopathy, and plantar fasciitis): a preliminary study.

BACKGROUND: Hyaluronic acid (HA) with a high molecular weight of 2700 kDa is approved in Japan to treat osteoarthritis of the knee, periarthritis scapulohumeralis, and knee pain associated with rheumatoid arthritis. The purpose of this preliminary study was to investigate the short-term efficacy, safety, and injectable volume of HA in the treatment of enthesopathies. METHODS: A total of 61 patients (16 with lateral epicondylitis, 14 with patellar tendinopathy, 15 with insertional Achilles tendinopathy, and 16 with plantar fasciitis) were each administered a single injection of HA (up to 2.5 ml). Efficacy and safety were assessed by comparing the visual analog scale (VAS) for pain and local symptoms before injection (baseline) and at 1 week after injection. We also investigated the injectable volume by means of the difference in syringe weight before and after injection and by the judgment of the administering investigator. RESULTS: The injection of HA resulted in a change in VAS (mean ± SD) of -2.20 ± 2.26 cm for the four sites overall and -2.55 ± 2.43 cm for lateral epicondylitis, -2.01 ± 2.16 cm for patellar tendinopathy, -1.80 ± 1.91 cm for insertional Achilles tendinopathy, and -2.38 ± 2.61 cm for plantar fasciitis. The injection of HA also improved local symptoms in each site. It was also determined that 2.5 ml of HA can be injected in each of the four sites. CONCLUSION: A single injection of HA resulted in similar improvements of pain in each of the four enthesopathies (lateral epicondylitis, patellar tendinopathy, insertional Achilles tendinopathy, and plantar fasciitis). These results suggest that HA could be clinically effective in the treatment of enthesopathies.

Anterior Ankle Impingement Syndrome With Spur Fragmentation: Is It an Os Talotibiale?

Background: Bone fragments are often found in ankles with anterior bony impingement. However, whether they are detached osteophytes or accessory bones remains unknown. Methods: Among the 66 continuously enrolled cases of ankles with anterior bony impingement, 32 had a fragment located at the anterior margin of the tibia. The cases of posterior impingement, lateral instability, osteochondral lesions, or free bodies simultaneously treated were excluded. The enrolled subjects were classified into 2 groups: ankles without (group A) and with remarkable spurs (group B). The patients' backgrounds, location of the fragments, clinical scores, and other parameters required to resume sports were compared. The Japanese Society for Surgery of the Foot (JSSF) ankle rating scale was used to evaluate preoperative and postoperative ankle conditions, and the Self-Administered Foot Evaluation Questionnaire (SAFE-Q) was used to evaluate postoperative sports abilities. Results: Eight (seven subjects) and 11 ankles were classified into groups A and B, respectively, and the mean age of the 18 patients was 25.4 (range, 16-37) years. No statistical differences in patient backgrounds or fragment sizes between the groups existed. In group A, the fragments were located on the lateral plateau in 7 of the 8 ankles, whereas in group B, their locations varied. The patients were followed up for a median of 48 months (range, 24-168). No complications were observed. The postoperative JSSF and SAFE-Q sports activity scores were significantly higher in group A than in group B (P <.01 and <.001, respectively). The postoperative term to return to their original sports activities was significantly shorter in group A (P < .05). Conclusion: Anterior bony fragments of the ankle without a remarkable spur were located at a specific site, and the results of arthroscopic treatment were better than in those with remarkable spurs. Such a fragment may be called an os talotibiale. Level of Evidence: Level III, retrospective cohort study.

Treatment of Symptomatic Os Supranaviculare in Athletes.

BACKGROUND: Although the incidence of os supranaviculare (OSSN) is generally low, symptomatic OSSN affects athletes. The aim of this study was to assess the variations of OSSN and the results of osteosynthesis between the OSSN and the navicular bone. METHODS: Eleven feet of 10 elite athletes with symptomatic OSSN were treated. There were 3 male and 7 female patients with an average age of 19 years. Eight feet exhibited navicular stress fracture (NSF). Operative treatment was performed in 9 feet of 8 patients and 2 conservatively. Seven OSSNs were fixed with 1 or 2 screw(s) according to their size, using an autologous bone graft. The accompanying NSF was also treated surgically in 4 feet. Foot condition was evaluated using the Japanese Society for Surgery of the Foot (JSSF) midfoot rating scale and sports activity score of the Self-Administered Foot Evaluation Questionnaire (SAFE-Q). RESULTS: The median OSSN was 12.7 mm in width, 5.6 mm in length, and 6.6 mm in height. The dorsal surface of the OSSN required at least 70 mm2 to be fixed using 2 screws. Seven OSSNs of 6 patients treated surgically successfully fused with the navicular. Two small OSSNs that were not stabilized with screws also fused after surgical treatment for NSF. However, one of the 2 OSSNs with NSF treated nonoperatively did not achieve fusion. The patients were followed up for 24-161 months. The median JSSF score improved from 87 to 97.7 postoperatively (P = .00312). The median postoperative SAFE-Q sports score was 84.8. All patients returned to their original activities. CONCLUSION: Our results suggest that osteosynthesis with autologous bone graft was effective for symptomatic OSSNs. Even when the OSSN was small and not suitable for internal fixation, treatment of NSF was effective for union of OSSNs. The OSSN possibly belongs to a part or subtype of NSF.

Osteochondral Lesion of the Tibial Plafond Induced by Malposition of Soft Suture Anchors Used for the Deltoid Ligament Repair: A Case Report.

CASE: A 24-year-old elite female rugby player complained of prolonged symptoms after a surgical repair of the deltoid ligament performed 2 years previously. Ankle arthroscopy revealed an osteochondral lesion in the tibial plafond at the medial gutter, with the fibers of the soft suture anchor exposed in the joint. The anchors were removed, and the cysts were filled with autogenous cancellous bone. The patient returned to the elite-level rugby games 5 months after the operation without any symptoms. CONCLUSION: We must be aware that even soft anchors can cause arthritis if improperly positioned.

Treatment of Intra-Articular Lesions After Posterior Inferior Tibiofibular Ligament Injury: A Case Series of Elite Rugby Players.

Background: Surgical intervention is not typically used to treat symptoms after mild tibiofibular ligament injuries without ankle dislocation or subluxation. Purpose: To describe outcomes in patients arthroscopically treated for unique intra-articular lesions after sustaining syndesmosis injury of the ankle. Study Design: Case series; Level of evidence, 4. Methods: A total of 11 elite male rugby players with a mean age of 21.0 years (range, 17-28 years) were referred to our hospital for prolonged posterior ankle pain after a high ankle sprain during rugby football. The patients were examined using standing view radiography, computed tomography (CT) and magnetic resonance imaging (MRI) to determine the extent of ligament damage. Posterior ankle arthroscopy was performed to examine intra-articular lesions. The patients were evaluated using the American Orthopaedic Foot and Ankle Society (AOFAS) ankle/hindfoot rating scale and sports activity score of the Self-Administered Foot Evaluation Questionnaire (SAFE-Q). Results: The average reduced tibiofibular overlap on the standing mortise view was 1.2 mm (range, 0.5-2.0 mm) compared with the opposite ankles. Mason type 1 fracture was detected on CT in 6 patients, and ossification of the interosseous membrane was detected in 2 patients. A bone bruise in the posterior malleolus was observed on MRI in all but 1 patient. Intra-articular fragments located in the posterior ankle were observed and removed arthroscopically. Symptoms improved rapidly after arthroscopic treatment in all patients. All patients returned to rugby games at a median of 11 weeks postoperatively. The median AOFAS scores improved from 77 preoperatively to 100 postoperatively (P < .01), and the median SAFE-Q sports activity subscale score improved from 49.4 to 100 (P < .01). Conclusion: All unique intra-articular lesions that developed in rugby football players after syndesmosis injury were able to be treated arthroscopically. Patients returned to playing rugby football without syndesmosis reduction. Posterior ankle arthroscopy was effective in patients with residual symptoms after syndesmosis injury.

Advancement of Periosteal and Capsular Complexes With or Without Augmentation Using a Free Graft From Lower Extensor Retinaculum: A Comparative Study With Propensity Score Matching.

Background: This study compared the outcome of the L-shaped (L-AD) advancement of the periosteal and capsular complexes with or without augmentation using a free graft of the lower extensor retinaculum (AUG) in patients with chronic lateral ankle instability. Methods: A matched pair analysis was performed of retrospectively collected medical records of patients undergoing lateral ankle ligament repair who had completed at least 2 years of follow-up. Patients who underwent L-AD with AUG and patients undergoing L-AD alone were matched for age, sex, stress radiography findings, and body mass index. Patients with general joint laxity, osteoarthritic changes in the ankle, and subtalar symptoms and who underwent simultaneous surgical treatment for conditions other than that for lateral ankle ligament were excluded. A total of 46 patients were included in the study (23 patients in each group). Clinical outcome scores and postoperative mechanical instability were compared. Results: The median American Orthopaedic Foot & Ankle Society (AOFAS) score improved significantly (P < .001) from 72 to 97 in the L-AD alone group and from 77 to 100 in the L-AD with AUG group. The mean (±SD) talar tilt angles improved significantly from 11.1 to 4.7 degrees postoperatively (P < .001) in the L-AD alone group vs 9.7 to 5.2 degrees (P < .001) in the L-AD with AUG group. The mean anterior drawer distances were improved significantly postoperatively from 6.4 to 4.7 mm (P < .001) in the L-AD alone group, and from 6.5 to 4.5 mm (P < .001) in the L-AD with AUG group. Conclusion: The L-AD technique significantly improved AOFAS scores and mechanical instability of ankles with chronic lateral instability with a very low complication rate. Additional augmentation using a free graft showed no advantages in the ankle with a talar tilt of <20 degrees. Level of Evidence: Level III, retrospective case-control series.

Fibrocartilaginous Bed Injury of the Posterior Tibial Tendon Sheath: A Report of 3 Cases.

CASES: Three athletes (2 female gymnasts and 1 male rugby player) complained of persistent posteromedial ankle pain after an ankle injury. Arthroscopy of the ankle and tendoscopy of the posterior tibial tendon (PTT) were performed in 2 patients with prolonged symptoms and in 1 patient with acute severe pain. A small rupture at the fibrocartilaginous bed of the PTT with pinhole communication between the PTT sheath and the ankle joint cavity was detected, and open repair of the fibrocartilaginous bed was performed. CONCLUSION: All patients returned to their respective sports without any residual symptoms after open repair of the fibrocartilaginous bed.

Arthroscopic Treatment of Posterior Ankle Impingement Syndrome: Mid-Term Clinical Results and a Learning Curve.

PURPOSE: To report mid-term clinical results of posterior ankle arthroscopy in the treatment of posterior ankle impingement syndrome (PAIS) and to assess the learning curve and its influence on the results. METHODS: This was a retrospective evaluation of the clinical outcomes of posterior ankle arthroscopy and its learning curve in a series of patients with PAIS. Demographic and clinical data, surgical time, the American Orthopaedic Foot Ankle Society (AOFAS) ankle/hindfoot scores, and time to resumption of sports were recorded. RESULTS: Fifty-nine patients with 72 posterior ankle arthroscopies were evaluated at a mean follow-up period of 60 months (24-133 months). Causes of PAIS were an os trigonum (50), a large posterior talar process (14), and soft-tissue impingement (8). There were 29 male and 30 female patients. The average age was 21.8 years (12-74 years). The average preoperative AOFAS score improved significantly from 79.6 to 97.6 postoperatively (P < .0001). The average time taken to resume training was 5.3 weeks, and the time to return to a competitive condition was 13.4 weeks. The times to resumption of training were shorter in elite athletes than local competitive athletes. The learning curve of the posterior ankle arthroscopy was detected and determined by a logarithmic trendline and moving averages. An experience of 26 cases was required to be proficient in posterior arthroscopies. The postoperative AOFAS scores were not statistically different between the initial and the latest 10 series each. CONCLUSIONS: The mid-term follow-up results of endoscopic treatment for the PAIS were good, with a high success rate in returning to sports activities. Although a learning curve effect was detected in our series of arthroscopic treatment for the PAIS due to os trigonum, a low volume of experience did not affect the results. LEVEL OF EVIDENCE: Level IV, therapeutic case series.

Morphologic Analysis of Nonosseous Talocalcaneal Coalitions Using 3D Reconstruction.

BACKGROUND: Resection of talocalcaneal coalitions has generally involved osseous coalitions. We attempted to evaluate the morphology of nonosseous talocalcaneal coalitions. This study aimed to investigate if the calcaneal articular surface area of feet with talocalcaneal coalitions is different than that of normal feet. METHODS: Twenty nonosseous talocalcaneal coalition cases with analyzable computed tomography (CT) scans were compared to 20 control cases. Three-dimensional models of the talus and calcaneus were constructed, and the surface areas of the posterior facet (SPF), whole talocalcaneal joint of the calcaneus (SWJ), and coalition site (SCS) of each 3D-CT model were measured. "Calibrated" values of the 2 groups were created to adjust for relative size of the tali and then compared. The preoperative and postoperative AOFAS Ankle-Hindfoot scale was calculated for 9 cases that had undergone single coalition resection. RESULTS: The calibrated SPF and SWJ were significantly greater in the coalition group than in the control group (40% and 12%, respectively). No significant difference was detected between the calibrated (SWJ - SCS) value of the coalition group and the calibrated SWJ value of the control group. The AOFAS scale was improved postoperatively in all 9 cases analyzed. CONCLUSION: The calcaneal articular surface of nonosseous talocalcaneal coalition feet in our series was larger than that of the normal feet. This study indicates that the total calcaneal articular surface after coalition resection may be comparable to the calcaneal articular surface of normal feet. We suggest that the indication for coalition resection be reconsidered for nonosseous coalition. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Severe Talonavicular Osteoarthritis After a Neglected Navicular Stress Fracture: A Case Report.

CASE: A 17-year-old high school rugby player complained of right midfoot pain for 18 months. Radiographs showed severe osteoarthritic changes in the right talonavicular joint. A navicular fracture, talonavicular joint narrowing, a talar head cyst, and proximal navicular fragmentation were detected on computed tomography (CT). The patient underwent removal of the osteochondral fragments and fracture reduction and returned to rugby 8 months postoperatively. CT showed a remodeling of the talonavicular joint 2 years postoperatively. CONCLUSION: In a young athlete, reconstruction of the talonavicular joint should be attempted before joint fusion, even if the joint shows signs of secondary osteoarthritis.

Pathoanatomy of the Jones Fracture in Male University Soccer Players.

BACKGROUND: Jones fractures are relatively common in soccer players and require an extended recovery period because this type of fracture has a high incidence of delayed union, nonunion, and refracture. There has been some previous research on risk factors for Jones fracture, but no study has yet investigated the effect of the length of the fifth metatarsal bone and the positional relationship of the articular surface of the fifth metatarsal bones and the tarsal bones. Clarification of the characteristics of the foot structure that predispose soccer players to Jones fracture may aid in the prevention of this injury. PURPOSE: To investigate the association between Jones fracture and foot structure as assessed with a mapping system on weightbearing dorsoplantar and lateral foot radiographs. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: We used a mapping system to evaluate the radiographs of 60 feet from 30 university soccer players with Jones fractures and a control group of 60 feet from 60 male university soccer players without Jones fracture. The groups were compared regarding the length of the fifth metatarsal and the positions of the metatarsal and tarsal bones. RESULTS: Analysis of weightbearing dorsoplantar foot radiographs showed that the fifth metatarsal was significantly longer and that its proximal tip was positioned more proximally in the Jones fracture group as compared with the control group. Analysis of weightbearing lateral foot radiographs showed that the reference points for the medial arch were significantly higher in the Jones fracture group than in the control group. CONCLUSION: This study indicated that the proximally longer fifth metatarsal may cause greater stress at the base of the fifth metatarsal bone because the lever arm becomes long. In addition, high medial longitudinal arch may contribute to increased load on the lateral side of the foot. Thus, these anatomic features may be useful to identify soccer players at high risk of Jones fracture at medical checkup.

Recent Developments in the Treatment of Ankle and Subtalar Instability.

It was nearly a centenary ago that severe ankle sprain was recognized as an injury of the ankle ligament(s). With the recent technological advances and tools in imaging and surgical procedures, the management of ankle sprains - including subtalar injuries - has drastically improved. The repair or reconstruction of ankle ligaments is getting more anatomical and less invasive than previously. More specifically, ligamentous reconstruction with tendon graft has been the gold standard in the management of severely damaged ligament, however, it does not reproduce the original ultrastructure of the ankle ligaments. The anatomical ligament structure of a ligament comprises a ligament with enthesis at both ends and the structure should also exhibit proprioceptive function. To date, it remains impossible to reconstruct a functionally intact and anatomical ligament. Cooperation of the regenerative medicine and surgical technology in expected to improve reconstructions of the ankle ligament, however, we need more time to develop a technology in reproducing the ideal ligament complex.

Osteochondral lesion of the tibial plafond treated with a retrograde osteochondral autograft: a report of two cases.

BACKGROUND: Osteochondral lesions (OCLs) of the tibial plafond (OLTPs) are rare, and few studies provide treatment recommendations. We describe two cases of an OLTP that were treated with retrograde osteochondral autograft. CASE REPORTS: The first case was a 27-year-old basketball player and the second case was a 38-year-old soccer player. We harvested osteochondral autografts from the nonweight-bearing area of the lateral femoral condyle of the patient's ipsilateral knees. The grafts were reversed and inserted into the bone tunnel reaching the OLTPs starting proximally and moving distally. The first patient was able to play professional basketball 14 months after the procedure and continues to play 5 years and 6 months later. The second patient was able to play recreational soccer 9 months after the procedure and continues to play 4 years later. CONCLUSION: Use of the retrograde osteochondral autograft produced satisfactory results including the return to sports. The retrograde osteochondral autograft can be considered recommendable for treating OLTPs.

Early bone in-growth ability of alumina ceramic implants loaded with tissue-engineered bone.

To enhance early bonding of an alumina ceramic implant to bone, we evaluated a method of seeding the implant surface with bone marrow mesenchymal cells that differentiated to osteoblasts and bone matrix prior to implantation. The usefulness of the method was evaluated in Japanese white rabbits. In our study, an alumina ceramic test piece loaded with differentiated osteoblasts and bone matrix by a tissue engineering technique was implanted into rabbit bones. Three weeks after the procedure, evaluation of mechanical bonding and histological examination were performed. Histological examination of the noncell-loaded implant surfaces showed no bone infiltration into the implant gap. However, the cell-loaded implant surfaces exhibited new bone infiltration into the implant gap with mechanical bonding. In the mechanical test, the average failure load was 0.60 kgf for the noncell-loaded side and 1.49 kgf for the cell-loaded side. Preculturing mesenchymal cells on the surface of the alumina ceramic prior to implantation increased the debonding strength by two and half times. The present findings indicate early bonding between the implant and bone three weeks after the procedure.

Relationship Between Displacement and Degenerative Changes of the Sesamoids in Hallux Valgus.

BACKGROUND: Although the tangential sesamoid view is used to visualize the sesamoid position relative to the first metatarsal head, correctly evaluating patients with severe varus of the first metatarsal is difficult. Computed tomography (CT) can be helpful due to its cross-sectional images in any plane. The purposes of this study were to evaluate the alignment of the tibial sesamoid and investigate the relationship between malalignment and degenerative change in the sesamoid metatarsal joint (SMJ) using simulated weight-bearing CT imaging in patients with hallux valgus. METHODS: In total, 269 feet from 142 patients with hallux valgus were included. The mean age was 63.7 years (range, 33-87 years). An anteroposterior weight-bearing radiograph was assessed for sesamoid position into 3 grades: grade 1, the tibial sesamoid was medial to the axis of the first metatarsal; grade 2, the tibial sesamoid was located below the first metatarsal axis; and grade 3, the tibial sesamoid was lateral to the first metatarsal axis. The hallux valgus and intermetatarsal angles (HVA and IMA, respectively) were measured. The lateral shift of the tibial sesamoid relative to the first metatarsal was classified into 3 grades on simulated weight-bearing CT classification: grade 1, tibial sesamoid was entirely medial to the intersesamoid ridge; grade 2, tibial sesamoid was subluxated laterally but located below the intersesamoid ridge; and grade 3, tibial sesamoid was located entirely lateral to the intersesamoid ridge. The differences of HVA and IMA in each grade were confirmed by using 1-way analysis of variance with Bonferroni post hoc corrections. Furthermore, multiple linear regression analysis was used to predict the degenerative change in the SMJ for age, sex, sesamoid position determined by CT or plain radiography, HVA, and IMA. The χ2 test was used for descriptive statistics to analyze the agreement between radiography or CT classifications of sesamoid position against degenerative change in the SMJ. RESULTS: Based on the radiographic classification of the tibial sesamoid position, 7 feet were classified as grade 1, 72 were grade 2, and 190 were grade 3, respectively. Based on the CT classification, 34 feet were classified as grade 1, 116 were grade 2, and 119 were grade 3. Degenerative change in SMJ progressed according to the sesamoid shift relative to the first metatarsal using either radiography or CT. In radiography, statistically significant differences were found except for the difference in HVA between grades 1 and 2. In addition, statistically significant differences were found between HVA and IMA, along with the grades in CT.In multiple linear regression, degenerative change was correlated with age and sesamoid position in CT and radiographic classifications. CONCLUSION: Our study showed that lateral shift of the tibial sesamoid increased in association with progression of the hallux valgus deformity. Furthermore, increasing lateral shift of the tibial sesamoid was associated with worsening degenerative change within the SMJ. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Pathogenesis of Fifth Metatarsal Fractures in College Soccer Players.

BACKGROUND: The pathogenesis of fifth metatarsal stress fractures remains uncertain. HYPOTHESIS: Physical characteristics and environmental factors, which have received limited attention in the literature thus far, might be involved in the development of fifth metatarsal stress fractures. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: To test the study hypothesis, a medical examination and survey of the living environment of collegiate soccer players was conducted and correlated with the existence of fifth metatarsal stress fractures. The survey and measurements were conducted in 273 male athletes from the same college soccer team between 2005 and 2013. A medical examination comprising assessment of stature, body weight, body mass index, foot-arch height ratio, toe-grip strength, quadriceps angle, leg-heel angle, functional reach test, single-leg standing time with eyes closed, straight-leg raise angle, finger-floor distance, heel-buttock distance, ankle joint range of motion, and a general joint laxity test were performed once a year, along with a questionnaire survey. The survey was also repeated when a fifth metatarsal stress fracture was diagnosed. The study participants were separated into a fifth metatarsal stress fracture injury group and a noninjury group. The measurement items and survey items were compared, and the association between the factors and the presence or absence of injuries was analyzed. RESULTS: Toe-grip strength was significantly weaker in the injury group compared with the noninjury group, suggesting that weak toe-grip is associated with fifth metatarsal stress fracture (P < .05). In addition, fifth metatarsal stress fractures were more common in the nondominant leg (P < .05). Between-group comparisons of the other items showed no statistically significant differences. CONCLUSION: The association between weak toe-grip strength and fifth metatarsal fracture suggests that weak toe-grip may lead to an increase in the load applied onto the lateral side of the foot, resulting in stress fracture. The finding of stress fracture being more common in the nondominant leg needs further study.