Painful Accessory Navicular and Spring Ligament Injuries in Athletes.

Painful accessory navicular and spring ligament injuries in athletes are different entities from more common posterior tibialis tendon problems seen in older individuals. These injuries typically affect running and jumping athletes, causing medial arch pain and in severe cases a pes planus deformity. Diagnosis requires a detailed physical examination, standing radiographs, and MRI. Initial treatment focuses on rest, immobilization, and restriction from sports. Orthotic insoles may alleviate minor pain, but many patients need surgery to expedite recovery and return to sports. The authors review their approach to these injuries and provide surgical tips along with expected rehabilitation to provide optimal outcomes.

Navicular drop is negatively associated with flexor hallucis brevis thickness in community-dwelling older adults.

BACKGROUND: Flatfoot is characterized as a lower longitudinal arch and is a common foot deformity in older adults. Foot intrinsic muscle dysfunction has been considered as one of the factors for a lower medial longitudinal arch. The objective of this study was to investigate the association of the navicular drop with the thickness of foot intrinsic muscles in older adults. RESEARCH QUESTION: Which intrinsic muscle contributes most to support the medial longitudinal arch in older adults? METHODS: We studied 88 community-dwelling older adults (mean age 74.2 ± 6.2 years). We measured the navicular height, the calcaneus inclination, and hallux valgus angle on the right foot in the sitting and standing positions using a 3D foot scanner. Then, we calculated the navicular drop and changes in the calcaneus inclination from the sitting to the standing position. The muscle thickness of the flexor hallucis brevis (FHB), flexor digitorum brevis (FDB), and abductor hallucis (AbH) was measured on the right foot using Bmode ultrasonography. RESULTS: Multiple regression analysis demonstrated that FHB thickness was significantly associated with navicular height in the standing positions (ß = 8.568, P = 0.016) as well as navicular drop (ß = -9.495, P = 0.037) after adjusting for age, sex, height, weight, and hallux valgus angle. There was no association with FDB or AbH. The thickness of any intrinsic muscle was not associated with the calcaneus inclination or changes in the calcaneus inclination. SIGNIFICANCE: Our data suggest that FHB plays an important role in preventing navicular drop and that intrinsic muscles likely do not contribute to the rearfoot angle in older adults.

Effects of the Short Foot Exercise With Neuromuscular Electrical Stimulation on Navicular Height in Flexible Flatfoot in Thailand: A Randomized Controlled Trial.

OBJECTIVES: Flatfoot, or low medial longitudinal arch, contributes to back and lower extremity injuries and is caused by weak abductor hallucis (AbdH) muscles. The purpose of this study was to investigate the effects of short foot exercise (SFE) alone or with neuromuscular electrical stimulation (NMES) on navicular height, the cross-sectional area (CSA) of the AbdH muscle, and AbdH muscle activity in flexible flatfoot. METHODS: Thirty-six otherwise healthy people with flexible flatfoot were randomly assigned to a group that received SFE with placebo NMES treatment (the control group) or a group that received both SFE and NMES treatment (the experimental group). Each group received 4 weeks of treatment (SFE alone or SFE with NMES). Navicular height, the CSA of the AbdH muscle, and AbdH muscle activity were assessed before and after the intervention. RESULTS: No significant differences were found in navicular height or the CSA of the AbdH muscle between the control and experimental groups, while AbdH muscle activity showed a statistically significant difference between the groups (SFE=73.9±11.0% of maximal voluntary isometric contraction [MVIC]; SFE with NMES=81.4±8.3% of MVIC; p<0.05). Moreover, the CSA of the AbdH muscle showed a statistically significant increase after treatment in the SFE with NMES group (pre-treatment=218.6±53.2 mm2; post-treatment=256.9±70.5 mm2; p<0.05). CONCLUSIONS: SFE with NMES was more effective than SFE alone in increasing AbdH muscle activity. Therefore, SFE with NMES should be recommended to correct or prevent abnormalities in people with flexible flatfoot by a physiotherapist or medical care team.

Measurement of Dorsal First Ray Mobility: A Topical Historical Review and Commentary.

Despite evidence that instability of the first ray (first metatarsal and medial cuneiform) alters the loading mechanics of the foot, surprisingly few studies have linked the condition with disorders of the foot. A factor limiting this research is the difficulty associated with measuring first ray mobility (FRM). To quantify dorsal FRM, clinicians and researchers have devised a variety of methods that impose a dorsally directed load, and record displacement. The methods include manual examination, radiographs, mechanical devices, and handheld rulers. Since different methods yield different results; each of these methods is worthy of scrutiny. This article reviews the methods used to quantify dorsal FRM and offers commentary on how the testing procedures could be standardized. The measurement of dorsal FRM informs surgical decisions, orthotic prescriptions, and research design strategies mostly as it pertains to the identification and treatment of first ray hypermobility. This review found sufficient support to recommend continued use of radiographs and mechanical devices for quantifying dorsal displacement, whereas measurements acquired with handheld rulers are prone to the same subjective error attributed to manual examination procedures. Since measures made with radiographs and existing mechanical devices have their own drawbacks, the commentary recommends ideas for standardizing the testing procedure and calls for the development of a next-generation device to measure dorsal FRM. This future device could be modeled after arthrometers that exist and are used to quantify stability at the knee and ankle. Level of Evidence: Level V, expert opinion.

Postoperative Medial Cuneiform Position Correlation With Patient-Reported Outcomes Following Cotton Osteotomy for Reconstruction of the Stage II Adult-Acquired Flatfoot Deformity.

BACKGROUND: Residual supination of the midfoot during reconstruction of the stage II adult-acquired flatfoot deformity (AAFD) is often addressed with a medial cuneiform (Cotton) osteotomy after adequate correction of the hindfoot valgus deformity. The purpose of this study was to determine if there was a correlation between postoperative alignment of the medial cuneiform and patient-reported outcomes. METHODS: Sixty-three feet in 61 patients with stage II AAFD who underwent a Cotton osteotomy as part of a flatfoot reconstruction were included in the study. Radiographic angles were measured on weightbearing lateral radiographs at a minimum of 40 weeks postoperatively. Pearson's correlation analysis was used to determine if there was an association between postoperative radiographic angles and Foot and Ankle Outcome Score (FAOS) at a minimum of 24 months postoperatively. Patients were also divided into mild plantarflexion (cuneiform articular angle [CAA] ≥-2 degrees) and moderate plantarflexion (CAA <-2 degrees) groups to evaluate for differences in clinical outcomes. RESULTS: Postoperative CAA was significantly positively correlated with the postoperative FAOS symptoms ( r = .27, P = .03), daily activities ( r = .29, P = .02), sports activities ( r = .26, P = .048), and quality of life ( r = .28, P = .02) subscales. Patients in the mild plantarflexion group had statistically and clinically better outcomes compared with the moderate plantarflexion group in the FAOS symptoms ( P = .04), daily activities ( P = .04), and sports activities ( P = .01) subscales. CONCLUSIONS: Our study suggests that the surgeon should avoid excessive plantarflexion of the medial cuneiform and use the Cotton osteotomy judiciously as part of a flatfoot reconstruction for stage II AAFD. LEVEL OF EVIDENCE: Level III, comparative series.

[Use of bisphosphonates in horses - a review]. / Einsatz von Bisphosphonaten beim Pferd ­ eine Literaturübersicht.

Systemic administration of tiludronate or clodronate decreases lameness in some horses suffering from navicular syndrome within 2-6 months of treatment. In horses that fail to respond to the first treatment, a follow-up treatment may still improve the lameness. Horses with a lameness duration of less than 6 months have better odds of experiencing improvement in lameness. Bisphosphonate (BP) treatment can result in renal damage, and it is recommended to assess renal function prior to and after treatment. Horses with pre-existing renal compromise should not be treated with BP, as this may promote deterioration of their renal status. Furthermore, BP should not be administered concurrently with non-steroidal antiinflammatory medications or other nephrotoxic drugs. One of the most common side effects of BP treatment in the horse is development of colic signs, which usually resolves with hand walking. In cases where medical treatment is warranted, N-butylscopolamine, xylazine, detomidine or butorphanol should be administered alone or in combination. The treatment with non-steroidal antiinflammatory medications is not recommended. In horses with muscle fasciculations, plasma electrolyte concentrations should be determined. The route of administration for BP should follow manufacturer recommendations, as local applications such as intraarticular injections or administration via regional limb perfusion may not be safe and are thus currently not recommended.

Validation of normalized truncated navicular height as a clinical assessment measure of static foot posture to determine flatfoot in children and adolescents: A cross sectional study.

BACKGROUND: Reliability of clinical measures of static foot posture has been widely debated. However, validity of these measures has not been fully established especially in a pediatric population. The purpose of the study was to investigate reliability and validity of normalized truncated navicular height (NTNH) in assessment of static foot posture to determine flatfoot in children and adolescents using radiographic measures as a criterion gold standard measure. METHODS: A sample of 612 participants aged 6-18 years (12.3±3.3) were enrolled in the study. Clinical assessment of static foot posture using NTNH was compared to the gold standard radiographic measures. Reliability, validity and diagnostic accuracy were investigated. The optimal cutoff point for flatfoot using NTNH was calculated. RESULTS: NTNH demonstrated sensitivity of 98.4%, high positive predictive (PV +) value of 89.2%. The positive likelihood ratio was 19 and the negative likelihood ratio was 0.02. The area under the receiver operating curve (AUC) was 0.96 indicating high validity and diagnostic accuracy of NTNH. The optimal cutoff point for diagnosing flatfoot was NTNH≤0.195. CONCLUSION: NTNH is a valid and diagnostically accurate clinical measure of static foot posture in children and adolescents.

Radiographic Evaluation of First Metatarsal and Medial Cuneiform Morphology in Juvenile Hallux Valgus.

BACKGROUND: Operative treatment of juvenile hallux valgus (JHV) has a high recurrence rate. The aim of this study was to better understand the pattern of radiographic deformity. METHODS: Standing radiographs of 93 feet in 57 patients with JHV, and 50 feet in 36 normal patients were measured. Measurements included: hallux valgus angle (HVA), first metatarsal physis status (open or closed), intermetatarsal angle (IMA), distal metatarsal articular angle (DMAA), Meary's angle, medial cuneiform angle (MCA), relative first to second metatarsal length ratio (1:2 MT ratio), cuneiform obliquity (CO), and congruency of the metatarsophalangeal joint (MTPJ). JHV groups were defined as normal (HVA 0-15 degrees), mild-moderate (HVA 15-35), or severe (HVA > 35) and were analyzed. RESULTS: Seventy of 93 feet (75%) with JHV presented with mild-moderate JHV (average HVA of 26.2 ± 5.6 degrees), and 23 feet (25%, 23/93) presented with severe JHV (average HVA of 41.9 ± 5.3 degrees). Multivariable analysis determined that DMAA ( P < .001), MCA ( P = .04), and congruency ( P < .001) were independently associated with JHV and its severity (normal vs mild-moderate vs severe). Severe JHV cases had larger DMAA ( P = .01), larger IMA ( P = .01), larger 1:2 MT ratio ( P = .02), and were less frequently congruent ( P = .03) compared with mild-moderate JHV cases. CONCLUSION: Deformity in JHV was highly correlated with both the proximal and distal morphology of the first metatarsal and medial cuneiform. Severe JHV was associated with increased bony deformity and increased incongruity of the MTPJ. Treatment should be individualized, but JHV treatment algorithms can take this information into account. LEVEL OF EVIDENCE: Level III, comparative study.

Comparison of Intercuneiform 1-2 Joint Mobility Between Hallux Valgus and Normal Feet Using Weightbearing Computed Tomography and 3-Dimensional Analysis.

BACKGROUND: An association has been reported between hallux valgus and hypermobility of the first ray, but subluxation of the intercuneiform 1-2 joint was also suspected in some cases. However, dynamics of the intercuneiform 1-2 joint has seldom been investigated. This study used weightbearing computed tomography (CT) and a 3-dimensional (3D) analysis system to evaluate displacement of the intercuneiform 1-2 joint, intercuneiform 2-3 joint, and second cuneonavicular joint due to weightbearing in hallux valgus and normal feet. METHODS: Patients were 11 women with hallux valgus (mean age, 56 years; mean hallux valgus angle, 43 degrees; mean first-second intermetatarsal angle, 22 degrees) and 11 women with normal feet (mean age, 57 years; mean hallux valgus angle, 14 degrees; mean first-second intermetatarsal angle, 9 degrees). Each patient was placed supine with the lower limbs extended, and CT was performed under nonweightbearing and weightbearing conditions (load equivalent to body weight). 3D models reconstructed from CT images were used to compare displacement of the intermediate cuneiform relative to the medial cuneiform under nonweightbearing and weightbearing conditions. RESULTS: Relative to the medial cuneiform, the middle cuneiform was displaced by 0.1 and 0.8 degrees due to dorsiflexion, 0.2 and 1.0 degrees due to inversion, and 0.7 and 0.7 degrees due to abduction in normal feet and feet with hallux valgus, respectively, with the latter having significantly greater dorsiflexion ( P = .0067) and inversion ( P = .0019). There was no significant intergroup difference at the intercuneiform 2-3 joint and second cuneonavicular joint. CONCLUSION: This study clarified the detailed load-induced displacement of the cuneiform 3-dimensionally. Compared with normal feet, hallux valgus feet had significantly greater mobility of the intercuneiform 1-2 joint, suggesting hypermobility of this joint. LEVEL OF EVIDENCE: Level III, case-control study.

Fluoroscopic and Gait Analyses for the Functional Performance of a Custom-Made Total Talonavicular Replacement.

The present study evaluated the restoration of joint function in a special clinical case: a professional rock climber who underwent an original total talonavicular replacement with a custom-made prosthesis after a complex articular fracture. Full body gait analysis and 3-dimensional joint kinematics using single-plane fluoroscopy were performed on the same day at the 30-month follow-up examination. Gait analysis was performed using stereophotogrammetric, dynamometric, electromyographic, and baropodometric systems. Gait analysis showed good restoration of rotation, as well as moment patterns in the main lower limb and foot joints in the operated leg. At the artificial tibiotalar joint, videofluoroscopic analysis revealed a flexion capability of about 20°, together with a few degrees of motion in the frontal and transverse planes. The neighboring joints of the foot did not present with severe kinematic abnormalities. A full talonavicular replacement can be a viable and effective solution for complex ankle injury sequelae, even in patients with highly demanding functionality.

A Finite Element Model of the Foot/Ankle to Evaluate Injury Risk in Various Postures.

The foot/ankle complex is frequently injured in many types of debilitating events, such as car crashes. Numerical models used to assess injury risk are typically minimally validated and do not account for ankle posture variations that frequently occur during these events. The purpose of this study was to evaluate a finite element model of the foot and ankle accounting for these positional changes. A model was constructed from computed tomography scans of a male cadaveric lower leg and was evaluated by comparing simulated bone positions and strain responses to experimental results at five postures in which fractures are commonly reported. The bone positions showed agreement typically within 6° or less in all anatomical directions, and strain matching was consistent with the range of errors observed in similar studies (typically within 50% of the average strains). Fracture thresholds and locations in each posture were also estimated to be similar to those reported in the literature (ranging from 6.3 kN in the neutral posture to 3.9 kN in combined eversion and external rotation). The least vulnerable posture was neutral, and all other postures had lower fracture thresholds, indicating that examination of the fracture threshold of the lower limb in the neutral posture alone may be an underestimation. This work presents an important step forward in the modeling of lower limb injury risk in altered ankle postures. Potential clinical applications of the model include the development of postural guidelines to minimize injury, as well as the evaluation of new protective systems.

Orthopedic Conditions of the Premature and Dysmature Foal.

Incomplete ossification of the cuboidal bones is a common finding in premature and dysmature foals, and possibly in foals with hypothyroidism. Radiographs of the carpus and tarsus should be performed in any high-risk foal to obtain a diagnosis. Goals of treatment include limiting weight bearing and exercise. The prognosis is guarded depending on the degree of incomplete ossification.

Genetic Influence on Accessory Navicular Bone in the Foot: A Korean Twin and Family Study.

An accessory navicular bone (AN) is the most common accessory ossicle in the foot. The presence of an AN bone can trigger various foot problems, such as posterior tibial tendon pathology, flattening of the medial longitudinal arch, and medial foot pain. Despite the clinical influence of presence of an AN in foot disease, the research regarding its inheritance is still insufficient. A total of 135 pairs of monozygotic (MZ) twins, 25 pairs of dizygotic (DZ) twins, and 676 singletons from families were enrolled in order to estimate genetic influences on AN. After confirmation of zygosity and family relationship with a tandem repeat marker kit and questionnaires, the presence and type of the AN was classified through bilateral feet radiographic examination. The heritability of an AN was estimated using quantitative genetic analysis based on a variance decomposition model considering various types of family relationships: father-offspring pair, mother-offspring pair, and pooled DZ twin and sibling pairs. As a result, approximately 40.96% of the participants in this study had an AN in either foot, with type II being the most common type. The heritability for the presence of any type of an AN in any foot was estimated as 0.88 (95% CI [0.82, 0.94]) after adjusting for age and sex. Specifically, type II AN showed the highest heritability of 0.82 (95% CI [0.71-0.93]). The high heritability of an AN found in this large twin and family study suggests that an AN is determined by the substantial influence of genetic factor.

A point mutation in Fgf9 impedes joint interzone formation leading to multiple synostoses syndrome.

Human multiple synostoses syndrome (SYNS) is an autosomal dominant disorder characterized by multiple joint fusions. We previously identified a point mutation (S99N) in FGF9 that causes human SYNS3. However, the physiological function of FGF9 during joint development and comprehensive molecular portraits of SYNS3 remain elusive. Here, we report that mice harboring the S99N mutation in Fgf9 develop the curly tail phenotype and partially or fully fused caudal vertebrae and limb joints, which mimic the major phenotypes of SYNS3 patients. Further study reveals that the S99N mutation in Fgf9 disrupts joint interzone formation by affecting the chondrogenic differentiation of mesenchymal cells at the early stage of joint development. Consistently, the limb bud micromass culture (LBMMC) assay shows that Fgf9 inhibits mesenchymal cell differentiation into chondrocytes by downregulating the expression of Sox6 and Sox9. However, the mutant protein does not exhibit the same inhibitory effect. We also show that Fgf9 is required for normal expression of Gdf5 in the prospective elbow and knee joints through its activation of Gdf5 promoter activity. Signal transduction assays indicate that the S99N mutation diminishes FGF signaling in developmental limb joints. Finally, we demonstrate that the conformational change in FGF9 resulting from the S99N mutation disrupts FGF9/FGFR/heparin interaction, which impedes FGF signaling in developmental joints. Taken together, we conclude that the S99N mutation in Fgf9 causes SYNS3 via the disturbance of joint interzone formation. These results further implicate the crucial role of Fgf9 during embryonic joint development.

Osteomyelitis of the accessory and body of the navicular bone: a case report.

A 16-year-old boy developed left foot pain of unknown cause that was unresponsive to conservative treatment, associated with fever and difficulty walking. He was admitted to our hospital with osteomyelitis of the accessory and body of the navicular bone. Surgery could not be performed because the patient had been diagnosed with Wiskott-Aldrich syndrome. After antibiotic therapy, laboratory abnormalities and pain had resolved. One year after treatment, the patient had returned to his original level of sports activity. Both an accessory navicular and the body of the navicular bone may develop osteomyelitis in immunocompromised patients; early diagnosis is important for prescribing effective conservative treatment.

Buttress Plating Versus Anterior-to-Posterior Lag Screws for Fixation of the Posterior Malleolus: A Biomechanical Study.

OBJECTIVES: The preferred method of fixation for posterior malleolus fractures remains controversial, and practices vary widely among surgeons. The purpose of this study was to compare anterior-to-posterior (AP) lag screws with posterior buttress plating for fixation of posterior malleolus fractures in a human cadaveric model. METHODS: Posterior malleolus fractures involving 30% of the distal tibial articular surface were created in 7 pairs of fresh frozen cadaveric ankles. One specimen in each pair was randomly assigned to fixation with either 2 AP lag screws or a one-third tubular buttress plate without supplemental lag screws. Each specimen was then subjected to cyclic loading from 0% to 50% of body weight for 5000 cycles followed by loading to failure. Outcome measures included permanent axial displacement during each test cycle (axial displacement at no load), peak axial displacement during each test cycle (axial displacement at 50% body weight), load at 1-mm axial displacement, ultimate load, and axial displacement at ultimate load. RESULTS: The buttress plate group showed significantly less peak axial displacement at all time points during cyclic loading. Permanent axial displacement was significantly less in the buttress plate group beginning at cycle 200. There were no significant differences between the 2 groups during load-to-failure testing. CONCLUSION: Posterior malleolus fractures treated with posterior buttress plating showed significantly less displacement during cyclical loading compared with fractures fixed with AP lag screws. Surgeons should consider these findings when selecting a fixation strategy for these common fractures. Further research is warranted to investigate the clinical implications of these biomechanical findings.

Weight-bearing three-dimensional computed tomography analysis of the forefoot in patients with flatfoot deformity.

BACKGROUND: The recent classifications for posterior tibial tendon dysfunction (PTTD) stage II are based on forefoot deformity, but there is still no consensus regarding a detailed explanation of the clinical condition. The purposes of this study were to clarify the clinical condition of flatfoot deformity using three-dimensional (3D) computed tomography (CT) imaging under loading on both healthy and flat feet and to compare 3D movement of the forefoot in response to load. METHODS: Ten volunteers and 10 PTTD stage II patients with symptomatic flatfoot deformity were examined. CT scans of 20 healthy and 20 flat feet were performed under non-loading and full weight-bearing conditions. Images of the tibia and foot arch bones (talus, calcaneus, navicular, and first and fifth metatarsal bones) were reconstructed into 3D models. Rotations of individual tarsal bone or metatarsal bone were described by the Eulerian angles. RESULTS: Compared with healthy feet, flat feet experienced plantarflexion of the fifth metatarsal bone relative to the first metatarsal bone under loading conditions. We defined this phenomenon as synonymous with forefoot varus on the coronal plane. CONCLUSIONS: The results of this study have clarified part of the clinical condition of the forefoot in flatfoot deformity and may have applications in basic research of the staging advancement and substage classification of PTTD.

Altered Kinematics and Time to Stabilization During Drop-Jump Landings in Individuals With or Without Functional Ankle Instability.

CONTEXT: It has been proposed that altered dynamic-control strategies during functional activity such as jump landings may partially explain recurrent instability in individuals with functional ankle instability (FAI). OBJECTIVE: To capture jump-landing time to stabilization (TTS) and ankle motion using a multisegment foot model among FAI, coper, and healthy control individuals. DESIGN: Cross-sectional study. SETTING: Laboratory. PATIENTS OR OTHER PARTICIPANTS: Participants were 23 individuals with a history of at least 1 ankle sprain and at least 2 episodes of giving way in the past year (FAI), 23 individuals with a history of a single ankle sprain and no subsequent episodes of instability (copers), and 23 individuals with no history of ankle sprain or instability in their lifetime (controls). Participants were matched for age, height, and weight (age = 23.3 ± 3.8 years, height = 1.71 ± 0.09 m, weight = 69.0 ± 13.7 kg). INTERVENTION(S): Ten single-legged drop jumps were recorded using a 12-camera Vicon MX motion-capture system and a strain-gauge force plate. MAIN OUTCOME MEASURES: Mediolateral (ML) and anteroposterior (AP) TTS in seconds, as well as forefoot and hindfoot sagittal- and frontal-plane angles at jump-landing initial contact and at the point of maximum vertical ground reaction force were calculated. RESULTS: For the forefoot and hindfoot in the sagittal plane, group differences were present at initial contact (forefoot: P = .043, hindfoot: P = .004). At the hindfoot, individuals with FAI displayed more dorsiflexion than the control and coper groups. Time to stabilization differed among groups (AP TTS: P < .001; ML TTS: P = .040). Anteroposterior TTS was longer in the coper group than in the FAI or control groups, and ML TTS was longer in the FAI group than in the control group. CONCLUSIONS: During jump landings, copers showed differences in sagittal-plane control, including less plantar flexion at initial contact and increased AP sway during stabilization, which may contribute to increased dynamic stability.