Aetiology, diagnosis, and treatment of brachymetatarsia: a narrative review

Brachymetatarsia (BM), or hypoplastic metatarsal, is an abnormal shortening of one or more metatarsal bones with a female-to-male ratio of 10.53:1. Different causes are described in the literature, such as congenital, acquired, or iatrogenic, associated with different conditions and syndromes. Its presence may develop deformity and pain; however, often feet are pain free and the major worries of patients are cosmetics. Non-operative treatments aim to improve the comfort of metatarsal heads and the possible dorsal conflict through comfortable shoes or the use of specific orthotics. The surgical treatment is anything but straightforward, with "one-stage" or "two stage" techniques, the latter better called "by gradual distraction". One-stage procedures are more rapid techniques but have limited ability to restore the desired length due to neurovascular compromise caused by acute lengthening. Insufficient correction is also possible. On the contrary, by gradual distraction procedures allow gradual distraction lengthening of more than 1.5 cm, but require the use of an external fixator, with a higher risk of complications in more than about 50% of surgeries. The adjacent metatarsal shortening should be considered in combination with other techniques, to diminish the excessive lengthening. In each case, surgeries should be always decided on each patient's concerns, deformities, and clinical needs.

[The talometatarsal-index ("TMT-Index") : A valuable X-ray parameter for differentiating between normal feet and planovalgus deformity in children and adolescents]

INTRODUCTION

The development of the shape of the shape from childhood to adulthood is a complex continuum. Deviations from this process occur frequently and, especially in asymptomatic patients, do not always include the need for therapeutic intervention. In the current S2-guideline on the juvenile flexible flatfoot, established x‑ray parameters for assessing the flatfoot deformity were judged to be sensitive, whereby no statement was made regarding the value of the parameters among themselves. The aim of the present work is to assess the talometatarsal Index (TMTInd) in comparison to established angle measurements.

METHODS

Twenty-two feet with and 22 feet without planovalgus deformity (age: 10-14 years) were investigated. Established radiological parameters (lateral view: talocalcaneal angle (TC-lat), calcaneal pitch angle (Calc-B), Costa-Bartani angle (Costa-B), talometatarsal‑I angle (TMTI-lat); dorsoplantar view: talometatarsal-I-basis angle (TMTIB), talonavicular coverage (TNG), calcaneal metatarsal- V angle (Calc-MTV), talocalcaneal angle (TC-dp), and talometatarsal‑I angle (TMTI-dp)) were measured on standardized X‑ray images and compared with the values of the TMTInd.

RESULTS

All parameters other than Calc-MTV, TC-dp, TC-lat and Calc‑B, showed a statistically significant difference between normal and planovalgus feet, although for almost all values measured (apart from TMTI-lat and TMTInd) there was a large overlap area (>10°) between the two groups. The comparison of TMTInd to all other parameters showed the highest discrimination factor (area-under-the-curve) for the TMTInd in the distinction between the groups.

CONCLUSION

Compared to conventional radiological parameters, the TMTInd shows the highest validity in the distinction between normal and planovalgus feet and can provide valuable information in clinical decision-making with regard to therapy specification.

Intra-bone nuclear DNA variability in Second World War metatarsal and metacarpal bones

DNA analysis of Second World War skeletal remains is challenging because of the limited yield of DNA that is usually recovered. Recent forensic research has focused on determining which skeletal elements are superior in their preservation of DNA, and little focus has been placed on measuring intra-bone variability. Metatarsals and metacarpals outperformed all the other bones in DNA yield when analyzing all representative skeletal elements of three Second World War victims, and intra-bone variability was not studied. Soft-tissue remnants were found to contribute to higher DNA yield in trabecular bone tissue. Because metatarsals and metacarpals are composed of trabecular epiphyses and a dense diaphysis, the goal of this study was to explore intra-bone variability in DNA content by measuring nuclear DNA quantity and quality using the PowerQuant System (Promega). A total of 193 bones from a single Second World War mass grave were examined. From each bone, DNA was extracted from the compact diaphysis and from both spongy epiphyses combined. This study confirms higher DNA quantity in epiphyses than diaphyses among all the bones analyzed, and more DNA was obtained from metacarpal epiphyses than from metatarsal epiphyses. Therefore, whenever the possibility for sampling both metacarpals and metatarsals from skeletal remains exists, collecting metacarpals is recommended. In cases in which the hands are missing, metatarsals should be sampled. In any case, epiphyses are a richer source of DNA than diaphyses.

Long Term Result of Weil Osteotomy and Callotasis for Bilateral Brachymetatarsia: A Case Report

Introduction:

Brachymetatarsia can be treated by lengthening of the affected metatarsals or shortening of the normal neighboring metatarsals. Combination of the two methods may be more effective rather than using one skill due to less complications.

Case Report:

A 56-year-old female patient with the bilateral first, fourth-ray brachymetatarsia underwent Weil osteotomy of the second, third, fifth metatarsals, and callotasis of the fourth metatarsal. Follow-up examination had been carried out since the surgery was done about 10 years ago.

Conclusions:

In the decade after observation, the patient was very satisfied with the shape and function of the feet, and no complications occurred.

Flexion location of the first metatarsophalangeal joint and the location of forefoot bend in general purpose women's footwear

BACKGROUND

General purpose footwear could have a built-in flexion location which may not match the anatomical fulcrum location for an individual's foot. Mismatched fulcra impact on joint function, and may delay healing of an injured first metatarsophalangeal joint (first MP joint). This study compared the location of the first MP joint in an asymptomatic sample of the South African female population to the bend location set within the lasts (used by footwear manufacturers) to find whether mismatches of the flexion locations of the joint to the bending location of the footwear were likely.

METHODS

The study used a three dimensional foot measurement database of 453 female participants to find the fulcrum location of the first MP joint. The distance between the heel and the first MP joint was expressed as a percentage of the overall length of the unshod foot. Similar measures for sandals and closed shoes were derived, and all were compared to manufacturer last data.

RESULTS

The location of first MP joint ranged from 70% to 79% of total foot length, significantly different from last design specifications of 63% or 66% (p<0.0001). The range of first MP joint fulcrum locations in the same size feet occurred in a wide 24mm mediolateral band under the forefoot, termed a flexion zone.

CONCLUSIONS

The first MP joint cannot properly function as a fulcrum unless footwear has a matching flexion location. Footwear designs should incorporate a wide flexion zone located under the forefoot to permit the range of first MP joint flexion locations. Recommendations to patients are to select appropriate flexible footwear to prevent shear forces, reduce strain, prevent injury and enable range of motion function and healing of injury.

Reliability of analysis of the bone mineral density of the second and fifth metatarsals using dual-energy x-ray absorptiometry (DXA)

Background

Metatarsal fractures, especially of the fifth metatarsal, are common injuries of the foot in a young athletic population, but the risk factors for this injury are not well understood. Dual-energy x-ray absorptiometry (DXA) provides reliable measures of regional bone mineral density to predict fracture risk in the hip and lumbar spine. Recently, sub-regional metatarsal reliability was established in fresh cadaveric specimens and associated with ultimate fracture force. The purpose of this study was to assess the reliability of DXA bone mineral density measurements of sub-regions of the second and fifth metatarsals in a young, active population.

Methods

Thirty two recreationally active individuals participated in the study, and the bone density of the second (2MT) and fifth (5MT) metatarsals of each subject was measured using a Hologic QDR x-ray bone densitometer. Scans were analyzed separately by two raters, and regional bone mineral density, bone mineral content, and area measurements were calculated for the proximal, shaft, and distal regions of the bone. Intra-rater, inter-rater, and scan-rescan reliability were then determined for each region.

Results

Proximal and shaft bone mineral density measurements of the second and fifth metatarsal were reliable. ICC's were variable across regions and metatarsals, with the distal region being the poorest.

Conclusions

Bone mineral density measurements of the metatarsals may be a better indicator of fracture risk of the metatarsals than whole body measurements. A reliable method for measuring the regional bone mineral densities of the metatarsals was found. However, inter-rater reliability and scan-rescan reliability for the distal regions were poor. Future research should examine the relationship between DXA bone mineral density measurements and fracture risk at the metatarsals.

Childhood metatarsal shaft fractures: treatment outcomes and relative indications for surgical intervention

PURPOSE

Although the epidemiology of childhood metatarsal fractures is known, the appropriate treatment has not been elucidated. This study was undertaken to ascertain the outcomes of both non-operative and surgical treatment of these common childhood injuries and to discern any indications for treatment.

METHODS

A retrospective review was performed of all children identified from 2006 to 2007 with a metatarsal fracture by the ICD-9 code, 825.25. After dividing the cohort into groups by age in years (0-5, 6-10, 11-15, 16 and older), we collected demographics, mechanism of injury, and associated injuries, as well as clinical information concerning metatarsal involvement, treatment, complications, return to activities/sports, and residual pain. Radiographic information was also collected, including fracture location, displacement, comminution, and union.

RESULTS

We identified 337 children that met the criteria. The mean age was 10.5 years (range 1.8-20.6). Only ten children had surgery. Only age, multiplicity of metatarsal fracture, and fracture translation was statistically different between the non-surgical and surgical cohorts. None of the patients under the age of 12 years underwent surgical intervention (p = 0.005). Evidence of multiple metatarsal fractures was seen in only 28 % of the non-surgical group compared to 70 % of the surgical group (p = 0.009). The amount of fragment translation significantly correlated with a decision for surgery (p = 0.001), but not angulation. Logistic regression demonstrated that, for every year of age, the likelihood for surgery increased by 32 % and that children were 6.6 times more likely to have surgery if they had multiple metatarsal fractures. Complete union was achieved in 84.6 %, with no difference in treatment groups regarding the time of release to full activities, and of the 50 delayed unions, only two required subsequent operative interventions. Return to sports took longer in the operative group, with a mean of 4.0 compared to 2.1 months (p < 0.001). Only 14 children complained of residual post-treatment pain and all of those cases had been treated without surgery. The presence of post-treatment pain did not correlate with the mechanism of injury or the amount of displacement.

CONCLUSION

Each metatarsal injury pattern is unique and surgeons should utilize their clinical judgment to determine appropriate treatment; however, there appears to be some relative indications for surgical treatment. Whereas open and articular fractures may be absolute indications for surgery, the relative indications for surgical intervention in metatarsal shaft fractures appear to be adolescent age and multiple fractures. Successful non-surgical management may consist of a short-leg walking cast for a mean of 4 weeks and activity restrictions for an additional month. However, children should be followed to radiographic union, since 15.4 % may have a delayed union and 4.3 % have short-term residual problems related to the injury.