BACKGROUND:

Most studies on the prevalence of flexible pes planus (FPP) have been conducted in pediatric populations and older adults. There is limited comparable information on these parameters for the adolescent age group. The purpose of this study was to report the prevalence of FPP and its association with body mass index (BMI), body height, and gender among healthy and fit adolescents.

METHODS:

The data for this study were derived from a medical database containing records of 17-year-old males and females before their recruitment into mandatory military service. Information on the disability codes associated with FPP according to the Regulations of Medical Fitness Determination was retrieved. Logistic regression models were used to assess the association between BMI, body height, and gender to various grades of FPP severity.

RESULTS:

The study cohort included 825 964 adolescents (467 412 males and 358 552 females). The prevalence was 12.4% for mild FPP and 3.8% for severe FPP among the males and 9.3% and 2.4%, respectively, for the females. An increased BMI was associated with FPP in both males (overweight: odds ratio [OR] 1.385, confidence interval [CI] 1.352-1.419, P < .001; obese: OR 1.765, CI 1.718-1.813, P < .001) and females (overweight: OR 1.408, CI 1.365-1.620, P < .001; obese: OR 1.549, CI 1.481-1.620, P < .001). Body height was associated with a decreased risk of FPP when the highest height quintile was compared with the lowest height quintile in both males (OR 0.782, CI 0.762-0.802, P < .001) and females (OR 0.730, CI 0.707-0.754, P < .001) for all FPP severity grades.

CONCLUSIONS:

There was a greater prevalence of FPP among males compared with females in a general healthy adolescent age group. FPP was associated with increased BMI and shorter body height for all grades of FPP severity.

LEVEL OF EVIDENCE:

Level II, diagnostic study.

Flexible flatfoot in childhood is a common cause for repetitive consultations and the diagnosis is verified by the clinical examination. In most cases the findings are age-dependent variants of the norm and if asymptomatic there is no need for treatment. In the first decade of life symptomatic flexible flatfoot should initially be treated with shoe inserts. Further diagnostic steps are required once conservative treatment is unsuccessful or a rigid structural deformity is found in the clinical examination. The underlying reasons may be neuropathic or structural anatomical in origin. Lateral column lengthening as described by Evans or minimally invasive arthroereisis are well established surgical options but for arthroereisis the number of long-term studies is low. In general the indications for surgical and conservative therapy have to be judged with caution although parents often see an urgent need for treatment.

BACKGROUND:

No single radiographic measurement takes into account complete foot alignment. We have created the Tripod Index (TI) to allow assessment of complex foot deformities using a standing anteroposterior (AP) radiograph of the foot. We hypothesized that TI would demonstrate good intraobserver and interobserver reliability and correlate with currently accepted radiographic parameters, in both flatfoot and cavovarus foot deformities.

METHODS:

Three groups of patients were studied: 26 patients (30 feet) with flatfoot, 29 patients (30 feet) with cavovarus foot, and 51 patients (60 feet) without foot deformity as controls. Weight-bearing radiographs were obtained: foot AP with a hemispherical marker around the heel plus standard lateral and hindfoot alignment views. Radiographic measurements were made by 2 blinded investigators. Statistical analysis included intraclass correlation coefficients (ICCs), correlation of the TI with existing radiographic measurements using Pearson coefficients, and comparison between patient groups using analysis of variance.

RESULTS:

Intraobserver and interobserver ICCs of TI (0.99 and 0.98, respectively) were excellent. In the flatfoot group, TI significantly correlated with AP talonavicular coverage angle (r = 0.43), medial cuneiform-fifth metatarsal height (r = -0.59), coronal plane hindfoot alignment (r = 0.53), and clinical hindfoot alignment (r = 0.39). In the cavovarus foot group, TI correlated significantly with AP talonavicular coverage angle (r = 0.77), calcaneal pitch angle (r = 0.39), medial cuneiform-fifth metatarsal height (r = -0.65), coronal plane hindfoot alignment (r = 0.55), and clinical hindfoot alignment (r = 0.61). Statistically significant differences between flatfoot-control and cavovarus foot-control were found in TI, AP talonavicular coverage angle, lateral talo-first metatarsal angle, calcaneal pitch angle, medial cuneiform-fifth metatarsal height, coronal plane hindfoot alignment, and clinical assessment of hindfoot alignment (all with P < .001).

CONCLUSION:

The TI was demonstrated to be a valid and reliable radiographic measurement to quantify the magnitude of complex foot deformities when evaluating flatfoot and cavovarus foot.

CLINICAL RELEVANCE:

The TI may be helpful as an integrated assessment of complex foot deformities. Further clinical studies are recommended.

LEVEL OF EVIDENCE:

Level III, retrospective comparative study.

BACKGROUND:

The acquisition of flatfoot by an adult is thought to primarily be caused by posterior tibial tendon dysfunction, although some other causes, such as congenital flexible flatfoot or an accessory navicular, may also be responsible. The objective of this study was to evaluate the bone rotation of each joint in the medial longitudinal arch (MLA) and compare the response in healthy feet with that in flat feet by analyzing the reconstructive three-dimensional (3D) CT image data during weightbearing.

METHODS:

CT scans of 20 healthy feet and 24 feet with flatfoot deformity were taken in non-load condition followed by full-body weightbearing condition. Images of the tibia and MLA bones (first metatarsal bone, cuneiforms, navicular, talus, and calcaneus) were reconstructed into 3D models. The volume merge method in three planes was used to calculate the bone-to-bone relative rotations.

FINDINGS:

Under loading conditions, the flatfoot dorsiflexed more in the first tarsometatarsal joint, and everted more in the talonavicular and talocalcaneal joints compared with the healthy foot. The total relative rotation was larger in the flatfoot compared with the healthy foot only in the first tarsometatarsal joint.

INTERPRETATION:

Supporting the MLA in the sagittal direction and the subtalar joint in the coronal direction may be useful for treating flatfoot deformity. The first tarsometatarsal joint may play an important role in diagnosing or treating flatfoot deformity.

Lateral column lengthening (LCL) has been shown to radiographically restore the medial longitudinal arch. However, the impact of LCL on foot function during gait has not been reported using validated clinical outcomes and gait analysis.Thirteen patients with a stage II flatfoot who had undergone unilateral LCL surgery and 13 matched control subjects completed self-reported pain and functional scales as well as a clinical examination. A custom force transducer was used to establish the maximum passive range of motion of first metatarsal dorsiflexion at 40 N of force. Foot kinematic data were collected during gait using 3-dimensional motion analysis techniques.Radiographic correction of the flatfoot was achieved in all cases. Despite this, most patients continued to report pain and dysfunction postoperatively. Participants post LCL demonstrated similar passive and active movement of the medial column when we compared the operated and the nonoperated sides. However, participants post LCL demonstrated significantly greater first metatarsal passive range of motion and first metatarsal dorsiflexion during gait than did controls (P < .01 for all pairwise comparisons).Patients undergoing LCL for correction of stage II adult-acquired flatfoot deformity experience mixed outcomes and similar foot kinematics as the uninvolved limb despite radiographic correction of deformity. These patients maintain a low arch posture similar to their uninvolved limb. The consequence is that first metatarsal movement operates at the end range of dorsiflexion and patients do not obtain full hindfoot inversion at push-off. Longitudinal data are necessary to make a more valid comparison of the effects of surgical correction measured using radiographs and dynamic foot posture during gait.Level III, comparative series.

OBJECTIVES:

The authors aim to present the common MRI appearances of surgically proven spring ligament tears as minimal radiological literature exists regarding injury to this increasingly important structure.

MATERIALS AND METHODS:

Our retrospective review identified a treatment group comprising 13 cases of surgically proven spring ligament injury and a 96-patient comparison group. All patients underwent standard musculoskeletal MRI sequences of the foot and ankle. Images were reviewed by a registrar-grade orthopedic surgeon and a consultant musculoskeletal radiologist for abnormalities of the spring ligament complex.

RESULTS:

MRI findings in relation to surgically proven injury of the superior-medial portion of the spring ligament included proximal thickening >5 mm in 92 % and distal thinning <2 mm in 85 % of proven injures to the spring ligament complex. Common abnormalities of the medio-plantar portion comprised ligament thickening >7 mm in 31 % and intra-substance signal heterogenicity demonstrated in 38 % of cases.

CONCLUSIONS:

The complex orientation of the medio-plantar ligament makes its evaluation unreliable due to the difficulty obtaining diagnostic quality imaging and our inability to correlate MRI findings in this portion of the ligament with surgically proven injury. However, MRI abnormalities of the superior-medial ligament are consistent, reproducible, and correlate with surgical pathology. As our incomplete understanding of the flexible flatfoot deformity evolves, our ability to recognize injury to the spring ligament may encourage novel surgical treatments looking to incorporate its repair or reconstruction into deformity correction.

OBJECTIVE:

This study aimed to characterize the effect of obesity on foot-ground contact in young individuals affected by Down syndrome (DS) during quiet upright stance.

DESIGN:

This is a cross-sectional study on 118 individuals with Down syndrome, 59 with obesity aged 3-18 yrs and 59 with normal weight, age- and sex-matched forming the control group. Both groups were evaluated while standing on a pressure-sensitive mat. Foot-ground contact was characterized using contact area and mean pressure calculated for the rearfoot, the midfoot, and the forefoot.

RESULTS:

The results show that obesity significantly influences the foot-ground interaction, with some differences related to sex. In particular, the females with obesity exhibited larger contact areas and higher plantar pressures (in the forefoot and the midfoot) with respect to the control group, whereas in the males with obesity, only the plantar pressures were found higher than those of the controls. Flatfoot is the prevalent arch type for both groups, but its incidence seems to be unrelated to obesity.

CONCLUSIONS:

The modifications introduced by obesity in foot-ground contact pressure and area may represent a factor capable of aggravating existing negative podiatric issues associated with Down syndrome. Thus, planning periodical monitoring of foot-ground contact during childhood and adolescence is recommended to avoid possible problems related to adverse effects of repeated excessive mechanical stresses on the plantar region.

PURPOSE.

To evaluate any correlation between various foot angles and their respective American Orthopaedic Foot and Ankle Society (AOFAS) scores for pain, and the effectiveness of a medial arch orthosis.

METHODS.

81 children with bilateral symptomatic flatfoot were randomised into orthosis (n=55) and control (n=26) groups. The orthosis group consisted of 33 male and 22 female patients aged 36 to 204 (mean, 99) months and they were given a medial arch support. The control group consisted of 15 male and 11 female patients aged 36 to 192 (mean, 100) months and they were managed with analgesics. Foot angles including anteroposterior (AP) and lateral talocalcaneal (TC) angles, AP and lateral talo- first metatarsal (TFM) angles, calcaneal pitch angle (in lateral plane), and talonavicular (TN) angle were measured, as were AOFAS scores for pain for the forefoot, midfoot, and hindfoot.

RESULTS.

After orthosis treatment, all AOFAS scores and all foot angles (except for the AP-TN angle) improved significantly. In the controls, all AOFAS scores (except for the midfoot score) and only the AP-TFM angle improved significantly. In the orthosis group, the AOFAS hindfoot score correlated positively with the lateral TC angle of the left foot (r=0.345, p=0.010) and negatively with the calcaneal pitch angle of the right foot (r=-0.33, p=0.015). In the control group, the lateral TFM angle of the left foot correlated negatively with the AOFAS forefoot (r=-0.566, p=0.003) and midfoot scores (r=-0.497, p=0.001), whereas the calcaneal pitch angle of the left foot correlated positively with the AOFAS forefoot score (r=0.497, p=0.010).

CONCLUSION.

Medial arch support orthosis significantly improved AOFAS scores and foot angles. Calcaneal pitch angle and lateral TC angle correlated well with AOFAS hindfoot scores.

PURPOSE.

To compare outcomes of different conservative treatments for flatfoot using the foot print index and valgus index.

METHODS.

150 symptomatic flatfoot patients and 50 controls (without any flatfoot or lower limb deformity) aged older than 8 years were evaluated. The diagnosis was based on pain during walking a distance, the great toe extension test, the valgus index, the foot print index (FPI), as well as eversion/ inversion and dorsiflexion at the ankle. The patients were unequally randomised into 4 treatment groups: (1) foot exercises (n=60), (2) use of the Thomas crooked and elongated heel with or without arch support (n=45), (3) use of the Rose Schwartz insoles (n=18), and (4) foot exercises combined with both footwear modifications (n=27).

RESULTS.

Of the 150 symptomatic flatfoot patients, 96 had severe flatfoot (FPI, >75) and 54 had incipient flatfoot (FPI, 45-74). The great toe extension test was positive in all 50 controls and 144 patients, and negative in 6 patients (p=0.1734, one-tailed test), which yielded a sensitivity of 96% and a positive predictive value of 74%. Symptoms correlated with the FPI (Chi squared=9.7, p=0.0213). Combining foot exercises and foot wear modifications achieved best outcome in terms of pain relief, gait improvement, and decrease in the FPI and valgus index.

CONCLUSION.

The great toe extension test was the best screening tool. The FPI was a good tool for diagnosing and grading of flatfoot and evaluating treatment progress. Combining foot exercises and foot wear modifications achieved the best outcome.

BACKGROUND:

Residual forefoot supination is commonly encountered during a flatfoot reconstruction, and a new technique for its treatment is described. Contrary to the standard Cotton osteotomy, a plantar closing wedge osteotomy of the medial cuneiform (PCWOMC) was performed, which has a number of advantages.

METHODS:

We followed 10 feet in 9 patients who had a PCWOMC performed as the last step of a standard flatfoot reconstruction for the correction of residual forefoot supination. These patients were evaluated pre- and postoperatively by standardized radiographic parameters, Short Form-12 (SF-12), and Foot and Ankle Outcome Score (FAOS).

RESULTS:

Patients were followed for an average of 25.8 months with final radiographic analysis performed at an average of 9.9 months. A significant difference (P < .001) between pre- and postoperative parameters was demonstrated for both lateral talus-first metatarsal angle and medial-cuneiform-to-ground distance. Likewise, there was a statistically significant improvement in the SF-12 score and 4 out of 5 components of the FAOS. One patient developed internal hardware-related symptoms, which were relieved following implant removal. All osteotomies healed uneventfully.

CONCLUSION:

A PCWOMC can be considered an alternative to the Cotton osteotomy for the treatment of forefoot supination deformity in adult flatfoot reconstruction. The main advantage of this technique over the Cotton osteotomy was simplicity, as an additional dorsal incision and bone graft were not required.

LEVEL OF EVIDENCE:

Level IV, retrospective case series.