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Bipartite hallucal sesamoid bones: Relationship with hallux valgus and metatarsal index

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The objective was to relate the incidence of the partition of the hallucal sesamoid bones to the size of the first metatarsal and the hallux valgus deformity. In a sample of 474 radiographs, the frequency of appearance of bipartite sesamoids was studied. The length and relative protrusion of the first metatarsal, and the hallux abductus angle, were measured and compared between the feet with and without sesamoid partition. The results showed that 14.6% of the feet studied had at least one partite sesamoid, that the sesamoid most frequently divided was the medial, and that unilateral partition was the most common. No difference was found in the incidence of partite sesamoids between men and women, or between left and right feet. Protrusion and length of the first metatarsal are greater in feet with partite sesamoids than in feet without this condition. A significantly higher incidence of bipartite medial sesamoid was obtained in feet with hallux valgus compared with normal feet.
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SCIENTIFIC ARTICLE
Bipartite hallucal sesamoid bones: relationship with hallux
valgus and metatarsal index
Pedro V. Munuera & Gabriel Domínguez & María Reina &
Piedad Trujillo
Received: 23 April 2007 /Revised: 15 June 2007 /Accepted: 8 July 2007 / Published online: 2 September 2007
#
ISS 2007
Abstract
Objective The objective was to relate the incidence of the
partition of the hallucal sesamoid bones to the size of the
first metatarsal and the hallux valgus deformity.
Materials and Methods In a sample of 474 radio graphs, the
frequency of appearance of bipartite sesamoids was studied.
The length and relative protrusion of the first metatarsal,
and the hallux abductus angle, were measured and
compared between the feet with and without sesamoid
partition.
Results The results showed that 14.6% of the feet studied
had at least one partite sesamoid, that the sesamoid most
frequently divided was the medial, and that unilateral
partition was the most common. No difference was found
in the incidence of partite sesamoids between men and
women, or between left and right feet.
Conclusion Protrusion and length of the first metatarsal are
greater in feet with partite sesamoids than in feet without
this condition. A significantly higher incidence of bipartite
medial sesamoid was obtained in feet with hallux valgus
compared with normal feet.
Keywords Bipartite hallucal sesamoid bones
.
First
metatarsal length
.
Hallux valgus
Introduction
The sesamoids are small bones of rounded or oval
morphology that owe their name to their similarity to the
seed of Sesamun indicum, a plant of eastern India used as a
purgative by physicians of Ancient Greece. The bones are
located completel y or partially within a tendon, and
although their anatomical location is usually the same,
some sesamoids appear infrequently. There are sesamoids
that always ossify and others that remain in a cartilaginous
or fibrocartilaginous state throughout life, so authors differ
in reporting the frequency of appearance of particular
sesamoids [1].
In the forefoot, two sesamoids are constantly found
under the head of the first metatarsal. These sesamoids
often develop from several ossification centres. When the
fusion of these ossification centres is defective, partition of
the sesamoids takes place [2]. The form and size of the
segments of a partite sesamoid can vary considerably and
have been described previously [3].
Sometimes, the presence of bipartite sesamoids has been
associated with a painful pathology of the great toe, but
association between hallux valgus and bipartite sesamoids
of the hallux has been reported on few occasions [47]. In
1992, Weil and Hill [4] carried out what is, as far as we
know, the only existing stud y on the frequency of
appearance of partite sesamoids in feet with and without
hallux valgus. Occasionally, it has also been associated with
variations in the length of the first metatarsalspecifically,
with the metatarsal formula index plus [7, 8]. We are
unaware of any studies in the medical literat ure that have
been carried out with the aim of determining whether such
a relationship exists or not.
Hallux valgus has often been associated with an increase
in the length of the first metatarsal [915]. This leads to the
Skeletal Radiol (2007) 36:1043 1050
DOI 10.1007/s00256-007-0359-6
P. V. Munuera
:
G. Domínguez
Department of Podiatrics, University of Seville,
Seville, Spain
P. V. Munuera (*)
:
G. Domínguez
:
M. Reina
:
P. Trujillo
Departamento de Podología,
Centro Docente de Fisioterapia y Podología,
C/ Avicena, s/n. 41009,
Seville, Spain
e-mail: pmunuera@us.es
notion that if the presence of bipartite sesamoids is related
to the hallux valgus deformity, it might also be related to
variations in the length of the first metatarsal.
This study has been designed with the aim of testing
whether the presence of bipartite sesamoids is greater in
feet with hallux valgus than in normal feet and determining
whether its appearance is more frequent in index plus feet
than in feet with another type of metatarsal index.
Materials and methods
The sample of this study comprised 474 feet (237 left and
237 right) belonging to 238 individuals (in 2 individuals,
only one foot was X-rayed), of whom 99 were women
and 139 men, with a mean age of 23.82±2.68 years old.
These participants were patients attending the Clinical
Podiatric Service at the University of Seville during the
period 20032006 due to hallux valgus or some other
problem of the rest of the foot (124), and podiatry students
volunteering to take part in the research (114). Each
participant was asked for written consent. The work was
approved by the Experimentation Ethics Committee of the
University of Seville.
The inclusion criteria were:
1. To be in the third decade of life (20 30 years old), so
that the growth physes had already closed [1618], and
to avoid degenerative alterations of the first metatarsal
that could affect its length
2. Never to have undergone osteoarticular surgery on the
first ray
3. Never to have suffered serious trauma to the first ray
that could have altered its osseous morphology
4. Not to suffer from degenerative osteo articular diseases
or neuromuscular imbalances
In each individual, weight-bearing dorsoplantar radiog-
raphy was performed with the two feet together, the ray
centred between the naviculars of both feet, with the tube
inclined 15° with respect to the vertical, and at a distance of
one metre from the foot. The kilovolts and milliamps per
second were fixed as indicated by the manufacturer (45 kV
and 4.0 mA). A digital image of each radiograph was
created, using a scanner, enabling the exploration of images
on positive film (EPSON EXPRESSION 1680 Pro®; Seiko
Epson Corporation, Nagano, Japan). The radiographic
measurements were made using AutoCAD® software
(Autodesk, San Rafael, CA, USA), whose effectiveness
for the measurement of radiographs has previously been
demonstrated [19]. The following measurements were
taken: relative protrusion between the first and second
metatarsals, to test whether the metatarsal formula is index
plus, index minus, or index plus-minus [20]; the length of
the first metatarsal, to test whether, in the feet with bipartite
sesamoids, only the protrusion of the first metatarsal varies,
or also the absolute length; the hallux abductus angle, to
compare it between feet with bipartite sesamoids and those
without; and length of the second metatarsal, to enable us to
express the length of the first metatarsal as a percentage of
the length of the second. All measurements were made by
the same observer (PVM), who also recorded the appear-
ance of partite sesamoids. Intra-observer reliability of these
radiographic measurements has previously been tested, and
the high intra-class correlation coefficient obtained showed
that it was acceptable [2123].
The first metatarsal protrusion is not an absolute
measurement, but rather a measurement of the length of
the first metatarsal relative to that of the second metatarsal.
This metatarsal protrusion distance is a measurement
between the two arcs that represent the first and second
metatarsal lengths. The method used to measure relative
metatarsal pr otrusion is that propos ed by Ha rdy and
Clapham [9]. This consisted of tracing a transverse line
on the tarsus, joining the posterior end of the tubercle of the
navicular and the lateral-distal end of the calcaneus. The
point where the axis of the second metatarsal intersects this
line was the centre of two arcs that pass through the distal-
most points of the first and second metatarsal heads
(Fig. 1). The relative protrusion between these two
metatarsals was obtained by measuring the distance
Fig. 1 Method of measuring the relative metatarsal protrusion
between the first and second metatarsals, according to Hardy and
Clapham [9]. p: protrusion
1044 Skeletal Radiol (2007) 36:1043 1050
between the two arcs. With the values for the protrusion of
the first metatarsal, three groups were created in accordance
with the metatarsal index described by Nilsonne [20]:
index plus-minus, if the protrusion of the first metatarsal was
equal to that of the second, or differed by values not exceeding
± 0.5 mm; index plus, if the protrusion of the first metatarsal
was greater than that of the second by more than 0.5 mm; and
index minus, if the protrusion of the first metatarsal was less
than that of the second by more than 0.5 mm.
The method of measuring the length of the first and
second metatarsals was that used by Heden and Sorto [10]
in 1981 (Fig. 2). It consisted of determining the distance
between the distal end of the metatarsal head and the
bisection of its base. The point that those authors identified
as bisection of the metatarsal base was the point of
intersection of the longitudinal axis of the metatarsal with
a line connecting the proximal-medial and proximal-lateral
ends of the metatarsal base.
In order to standardise the measurement of the length of
the first metatarsal, its value was expressed as a percentage
of the total length of the second metatarsal. This procedure
was previously carried out to the same end by other authors
[13, 24]. The hallux abductus angle was measured in
accordance with the procedure described by Coughlin et al.
[25]. The values of this angle were used to create two
groups: feet without hallux valgus, in which the hallux
abductus angle was less than or equal to 15°; and feet with
hallux valgus, in which this angle exceeded 15° [25].
ThedatawereanalysedusingtheSPSS14.0for
Windows (SPSS Science, Chicago, IL, USA). A descriptive
analysis was made of the frequency of appearance of
bipartite sesamoids, their distribution b y gender, the
bilaterality, and the groups created. The descriptive analysis
also yielded the mean, standard deviation, and 95%
confidence interval for each radiographic measurement.
The frequency of appearance of bipartite sesamoids was
compared between the three types of metatarsal index,
using the Chi-squared test, comparing the groups two by
two. The Chi-squared test was also used to compare the
occurrence of bipartite sesamoids between feet with and
those without hallux valgus, between men and women, and
between left and right feet. In addition, the values for first
metatarsal protrusion, length of the first metatarsal, and
hallux abductus angle were compared between the feet that
had bipartite sesamoids and those that did not, using
Students t test for independent samples. The use of this
statistical test was decided on after checking that the data
Fig. 2 Method of measuring the first metatarsal length. A: distal end
of the first metatarsal head; B: point of intersection of the first
metatarsal longitudinal axis with a line connecting the proximal-
medial and proximal-lateral ends of the metatarsal base
Table 1 Frequency of appearance and distribution of partite sesamoids
Participants (N=238) Feet (N=474) Total amount
Male (n=139) Female (n=99) Male (n=277) Female (n =197) Medial Lateral
Medial unilateral 8 14 8 14 22
Medial bilateral 8 8 16 16 32
Lateral unilateral 8 2 8 2 10
Lateral bilateral 1 0 2 0 2
Both unilateral 2 0 2 0 2 2
Both bilateral 1 0 2 0 2 2
Medial unilateral in one foot,
lateral unilateral in the other
10 20 11
Total 29 24 40 32 59 17
Skeletal Radiol (2007) 36:1043 1050 1045
followed a normal distribution using the Kolmogorov
Smirnov test. P values below 0.05 were considered
statistically significant.
Results
Frequency of appearance and distribution of partite
sesamoids
In the 474 feet studied, 76 partite sesamoids were observed.
We found one foot with tripartite medial sesamoid, one foot
with multipartite medial sesamoid, and one foot with
tripartite lateral sesamoid. The remaining cases were all
bipartite sesamoids. These results are shown in Table 1.
Comparison of the male feet in which there was at least one
partite sesamoid with the female feet in which there was at
least one partite sesamoid yielded a Pearson Chi-squared
value of 0.73, meaning there was no difference regarding
the frequency of appearance of parti te sesamoids between
men and women.
With regard to the side affected, the sample studied
included 237 left feet and 237 right feet. Twenty-eight
medial sesamoids and 8 lateral sesamoids were found to be
partite in left feet. Twenty-nine medial sesamoids and
8 laterals were found to be partite in right feet. There was
no significant difference in the occurrence of partite
sesamoids between left and right feet (P=0.90).
Bipartite sesamoids according to the metatarsal index
and the size of the first metatarsal
The descriptive values of the radiographic measurements
made in all the participants in this study are shown in
Table 2. According to the method used in this study to
measure the protrusion of the first metatarsal, 71.5% of the
feet were index plus type, 19.6% of the feet were index
minus type, and 8.9% of the feet were index plus-minus
type. The distribution of partite sesamoids according to the
metatarsal index is shown in Table 3. The results of
comparing the frequency with which the feet of the three
groups had partition in any of the sesamoids are shown in
Table 4. The differences were not signifi cant. In contrast,
when comparing the values of the protrusion and the length
of the first metatarsal between the feet that had partite
sesamoids and those that did not, significant differences
were obtained. There was also a significant difference when
these values were compared between the feet that had
partition in the medial sesamoid and those that did not.
However, the difference was not significant when compar-
ing between feet that had partition in the lateral sesamoid
and those that did not. The results of these comparisons can
be seen in Table 5.
Bipartite sesamoids in feet with and without hallux valgus
Of the 474 feet studied, 119 (25.1%) had a hallux abductus
angle great er than 15°, and 355 (74.9%) had a hallux
abductus angle equal to or less than 15°. The distribution of
partite sesamoids according to the hallux abductus angle is
shown in Table 6. In 3 feet without hallux valgus and in 1
foot with hallux valgus, both the medial and the lateral
sesamoid were partite. When comparing the frequency of
partition in either of the two sesamoids between feet with
and without hallux valgus using the Pearson Chi-squared
test, the difference was significant (P<0.0001). When
comparing the frequency of partition in the medial
sesamoid between feet with and without hallux valgus, the
difference was also significant (P<0.0001). However, when
comparing the frequency of partition in the lateral sesamoid
between feet with and without hallux valgus, there was no
significant difference ( P=0.99). When comparing the
hallux abductus angle values between the feet that had
partite sesam oids and those that did not, significant differ-
ences were obtained. The difference was also signi ficant
Table 2 Mean, standard deviation, and 95% confidence interval of
the radiographic variables measured
Mean ± SD 95% CI
Hallux abductus angle (°) 12.4±6.8 11.813.1
First metatarsal length (%) 85.2±3.0 84.985.4
First metatarsal protrusion (mm) 2.2±3.0 1.92.5
Table 3 Distribution of partite sesamoids according to the metatarsal
index
Feet with
partite sesamoids
(%)
Partite
sesamoids
Total (%)
Medial Lateral
Index plus 56/339 (16.5) 46 13 59 (80.8)
Index minus 9/93 (9.7) 8 1 9 (12.3)
Index
plus-minus
4/42 (9.5) 3 2 5 (6.9)
Total 69/474 (14.6) 57 16 73 (100)
Table 4 Pearson Chi-squared test to compare the frequency of
appearance of partite sesamoids among the three groups created
according to the protrusion of the first metatarsal
P value
Index plus vs. index minus 0.11
Index plus vs. index plus-minus 0.24
Index minus vs. index minus 0.98
1046 Skeletal Radiol (2007) 36:1043 1050
when these values were compared for the feet that had
partition in the medial sesamoid (Fig. 3). However, the
difference was not significant when compared for the feet
that had partition in the lateral sesamoid. The results of this
comparison can be seen in Table 7.
Discussion
Intra-observer reliability of the measurement procedure has
been tested by the authors in previous works [2123]. In
those studies, the reproducibility of the measurement
procedure was checked by using five radiographs chosen
at random from each group, and by taking the measure-
ments on three occasions, with intervals of a week between
measurements. The data obtained were used to calculate the
intra-class correlation coefficient, which was greater than
0.90 for these measurem ents. According to these data, the
reproducibility of the measurements is acceptable with the
methods used.
Frequency of appearance and distribution of partite
sesamoids
Several earlier works have reported data on the frequency of
partition in the sesamoids of the first metatarsophalangeal
joint. The percentage can vary from 4% [26, 27] to 33.5%
[28]. Our results regarding the frequency of appearance
were close to those of Dobas and Silvers [29], who reported
that 19.3% of the feet in their sample had at least one partite
sesamoid, and those of Inge and Ferguson [3], who reported
a frequency of 10.7%. We observed that 15.2% of the feet
in our samp le had at least one partite sesamoid. We
coincide with all the authors consulted in that the sesamoid
most frequently found to be partite was the medial [24, 8,
2630]. Some authors attribute the cause to the fact that the
medial sesamoid is more subject to trauma than the lateral
one because of its location [3, 6, 28, 30], as in normal
conditions the medial sesamoid is found more plantar than
the lateral [31].
With regard to bilaterality, the literature contains different
opinions. Some authors, such as García and Parkes [32]or
Jahss [2], state that the most frequent circumstance is that
the sesamoids are bilaterally partite, while others, such as
Rodeo et al. [30] or Inge and Ferguson [3], dissent, claiming
that they are most frequently unilateral. Our results were
more in concordance with the authors who assert that it is
more frequent to find unilateral partition. Specifically, these
results were similar to those obtained by Dobas and Silvers
[29], who reported 35.7% of bilaterality for the tibial
sesamoid, and 4.3% of bilaterality for the peroneal sesa-
moid. Fifty-three of the participants of our sample had
partite sesamoids, of whom 19 (34%) had partite sesamoids
bilaterally.
We have found few studies addressing the distribution of
partite sesamoids between men and women. Rodeo et al.
[30] sustained that the incidence was equal for the two
sexes. According to the data of Dobas and Silvers [29],
20.9% of the male feet and 17.1% of the female feet studied
had partition in one or more sesamoids. Although they did
not make a statistical analysis to compare these values
between men and women, we can see that the percentages
are very similar. Carpintero et al. [8], however, observed a
significantly higher incidence of partite sesamoids in
female feet than in male feet. The results of our study were
Table 5 Comparison of the protrusion and length of the first metatarsal between feet with one or more partite sesamoids and those without,
between feet with partite medial sesamoid and those without, and between feet with partite lateral sesamoid and those without
Mean ± SD Mean ± SD P
One or more partite sesamoids No partition
First metatarsal protrusion 3.4±3.1 mm First metatarsal protrusion 1.9±3.0 mm < 0.0001*
First metatarsal length 86.1±3.5% First metatarsal length 85.0±2.8% 0.006*
Medial sesamoid partition No partition
First metatarsal protrusion 3.3±3.2 mm First metatarsal protrusion 2.0±3.0 mm 0.003*
First metatarsal length 86.1±3.5% First metatarsal protrusion 85.0±2.8% 0.009*
Lateral sesamoid partition No partition
First metatarsal protrusion 3.3±2.4 mm First metatarsal protrusion 2.1±3.3 mm 0.122
First metatarsal length 85.4±3.2% First metatarsal protrusion 85.1±2.9% 0.739
*Significant difference
Table 6 Distribution of partite sesamoids according to the hallux
abductus angle
Feet with partite
sesamoids (%)
Partite sesamoids Total
Medial Lateral
HAA>15° 35/119 (29.4) 32 4 36
HAA<15° 34/355 (9.6) 25 12 37
Total 69/474 (14.6) 57 16 73
HAA: hallux abductus angle
Skeletal Radiol (2007) 36:1043 1050 1047
in accordance with those works that reported a similar
incidence for the two sexes.
With regard to the side affected, we studied the same
number of left and right feet, and found practically the same
number of partite medial and lateral sesamoids in the feet of
both sides. This similarity in the distribution of partite
sesamoids between left and right feet was also observed by
Dobas and Silvers [29], and by Kiter et al. [27].
Bipartite sesamoids according to the metatarsal index
and the size of the first metatarsal
We found only on e study associating partition of the
sesamoids with the metatarsal index [ 8 ]. In that work, the
authors reported a higher frequency of bipartite sesamoids
in Egyptian and index plus feet. In our sample, we observed
that the percentage of index plus feet in which partite
sesamoids appeared was higher than for index minus or
index plus-minus feet. However, the Chi-squared test did
not show significant differences in the frequency of
appearance of partite sesamoids among the three groups.
In contrast, the group of feet with partite sesamoids showed
greater length and greater protrusion of the first metatarsal.
Carpintero et al. [8] attributed this higher incidence of
bipartite sesamoids in index plus type feet to the increase
in pressure that a longer first metatarsal exerts on the
sesamoids.
The sesam oids appear wh ere tendons change their
direction, and in these zones they protect the tendon and
give it mechanical support. The hallucal sesamoids, besides
protecting the tendon of the flexor hallucis longus, give
mechanical support to the intrinsic musculature partially
inserted in them, so that the vector of plantar force is
greater on the hallux, helping to stabilise the hallux on the
ground during the push-o ff phase [33]. It is possible that the
plantar intrinsic musculature of the hallux exert s greater
traction on the sesamoids by passing under a metatars al that
is longer and has more protrusion. If the tension received in
the sesamoids were sufficient to fragment the ossification
centre and div ide it into two (o r more) nuclei, the
subsequent ossification of these separate centres would
give rise to partition of the sesamoid. It is thought that the
Fig. 3 Bilateral bipartite medial
sesamoid in a patient with
bilateral index plus and hallux
valgus. Hallux abductus angle
value is shown for the right foot.
Index plus is show for the left
foot. Arrows bipartite medial
sesamoid
Table 7 Comparison of the
hallux abductus angle between
feet with one or more partite
sesamoids and those without,
between feet with partite me-
dial sesamoid and without, and
between feet with partite lateral
sesamoid and those without
*Significant difference
Mean ± SD Mean ± SD P
One or more partite sesamoids No partition
Hallux abductus angle 16.0±6.8° Hallux abductus angle 11.8±6.6° < 0.0001*
Medial sesamoid partition No partition
Hallux abductus angle 16.7±6.8° Hallux abductus angle 11.8 ± 6.6° < 0.0001*
Lateral sesamoid partition No partition
Hallux abductus angle 12.4±5.1° Hallux abductus angle 12.4 ± 6.8° 1.00
1048 Skeletal Radiol (2007) 36:1043 1050
defective fusion of various centres of ossification is the
cause of partition in the sesamoids [2, 3 , 26]. Further
research would be necessary with regard to how the size of
the first metatarsal could affect partition of the sesamoids.
Bipartite sesamoids in feet with and without hallux valgus
Apart from Weil and Hill [4], who specifically associated
the hallux valgus deformity with the presence of bipartite
sesamoids, few authors have reported the presence of
partite sesamoids in feet with this deformity [57]. Weil
and Hill [4 ], in a retrospective radiographic study, detected
that 32.3% of the 500 feet with hallux valgus studied had
bipartite tibial sesamoid, compared with 15.2% of the 500
feet without hallux valgus in their sample. The authors
concluded that there was a high incidence of bipartism in
hallux valgus, and that it could be a contributory factor in
the development of this deformity. In our study, the
incidence of partite sesamoids was higher in feet with
hallux valgus than in normal feet. The Chi-squared test
showed that this was a significant difference. The incidence
of partition in the feet with hallux valgus approached that
reported by Weil and Hill [4]. Furthermore, comparison of
the hallux abductus angle between the group of feet in
which there was partition of one or more sesamoids and the
group of feet without such partition showed a statistically
significant difference ( P<0.0001). However, the two
comparisons made in this section of the study (Chi-squared
and Students t tests) showed no significant difference when
this comparison was limited to a bipartite lateral sesamoid.
This suggests that the differences observed specifically
involve the medial sesamoid.
Although it has been demonstrated that there is a higher
incidence of partition of the medial sesamoid in feet with
hallux valgus, it is not clear whether the partition occurs as
a result of the deformity or, contrarily, the development of
the deformity is furthered by the presence of a partite
sesamoid. Assuming the following hypotheses, we can
deduce that the medial sesamoid is divided as a conse-
quence of the hallux valgus deformity: it is known that in
the advanced hallux valgus deformity, the medial sesamoid
changes to a more plantar position and falls below the
intersesamoid plantar crest of the first metatarsal, which
ends up eroding it [26, 34]. This would result in excessive
trauma and stress in the medial sesamoid, which could
cause the partition of the sesamoid if such stress fragments
the ossification centre and the resul ting nuclei do not fuse.
It is also known that the abductor hallucis muscle produces
more flexion than abduction when the hallux rotates in
valgus as the deformity advances [7, 35]. This would
increase the antero-posterior tension received by the medial
sesamoid, and could contribute to the transverse division of
the medial sesamoid before it ossifies.
Weil and Hill [4] claimed that a bipartite medial
sesamoid could contribute to the development of the hallux
valgus deformity. T hey asserted that when there is a
transverse separation of the sesamoid, a mechanical
lengthening of the musculature takes place on the medial
side of the metatarsophalang eal joint, creating the tendency
towards hallux abductus. However, Aper et al. [33, 36]
demonstrated that excision of the distal half of the medial
sesamoid did not compromise the normal working of the
flexor musculature of the hallux.
Whether partition of the medial sesamoid promotes
hallux valgus, or hallux valgus promotes partition of the
medial sesamoid, remains unknown. What is put forward
by the authors in this section of the work is no more than a
hypothesis. A study comparing the incidence of partite
tibial sesam oid between feet in which hallux valgus has
begun before sesamoid ossification starts and feet in which
hallux valgus has appeared after ossification of the
sesamoids would help to resolve this question.
Conclusion
In the sample studied in this work, partition of the hallucal
sesamoids affected men and women, and the left and right
sides, equally, and was more frequent unilaterally. The feet
with partition of one or more sesamoids had greater
protrusion and greater length of the first metatarsal than the
feet without partite sesamoids. A significantly higher
incidence of partition of the medial sesamoid was observed
in the feet with hallux valgus than in the feet without hallux
valgus. However, it remains unknown whether the partition
of the medial sesamoid is the cause or the consequence of
this deformity.
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1050 Skeletal Radiol (2007) 36:1043 1050
... The imaging retrospective study of 500 cases of HV and 500 cases of non-HV foot in Theumann et al. [6] showed that the incidence of multiple seed bone in HV foot (32.3%) was significantly higher than that in non-HV foot (15.2%). Munuera et al. [8] found that there were significant differences between the HV angle of the multiseeded and nonfractionated feet by 474 foot imaging studies. Usually, there are two sesamoid below the head of the first metatarsal, the inner side one named tibial hallux sesamoid (THS) and the offside one named fibular hallux sesamoid (FHS); besides, THS is bigger than FHS [9][10][11]. ...
... Thus far, physical examination, radiographs, and other specialized studies assist with the classification of sesamoid pathology [7,8]. And the main treatment about HV is surgery which includes tissue surgery and osseous surgery. ...
Article
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The hallucal sesamoid bones (HSBs), having an important role in reducing load per unit area on the first metatarsal head, can be injured commonly which also affected the first metatarsophalangeal joint and the surrounding structure. Meanwhile, differences among each HSB type may be a major factor affecting the occurrence and development of HV. So far, many researchers had learned that there are three different conditions in hallucal sesamoid bone affecting the choice of clinical surgery corresponding to different solutions in clinic. Thus, it is necessary to study the anatomical morphological characteristics of the HSB which can be helpful in clinical diagnosis and treatment, especially hallux valgus (HV). 150 X-ray and three-dimensional (3D) computed tomographic (CT) images consist of 72 left and 78 right metatarsals were applied in this anatomic study between two variables and showed by a simple scatter plot. The first metatarsophalangeal joint is divided into four different types: type I (no HSB, 1.3%), type II (with one HSB, 0.07%), type IIIa (with two HSBs when THB is bigger, 28%), type IIIb (with two HSBs when FHB is bigger, 65.3%), and type IV (with three HSBs, 4.7%). There was no statistical difference between the left and right sides, except HVA, Meary, and pitch (P
... Bipartite sesamoids may be a variation of normal anatomy. It has been estimated that 14.6% of feet have at least one partite sesamoid, most frequently the medial sesamoid [10]. Bipartite sesamoids may be confused with a single sesamoid with fracture. ...
... Different variants have been described, of which the bipartite medial sesamoid seems to be the most common variant (up to 14%). [2][3][4][5] Turf toe injury usually occurs in sports activities. 6,7 A commonly proposed injury mechanism is forced axial loading onto the dorsally extended first MTP joint. ...
Article
Full-text available
We present a case of a 25-year-old male professional soccer player who complained of severe pain over the first metatarsal head after opponent contact during a soccer game. Clinical findings showed swelling and tenderness. Initial radiographs showed a diastasis of a bipartite medial sesamoid between the fragments as compared to radiographs taken 4 years earlier of the same foot. A computed tomography scan was performed objectifying the widened interval and also showing an angulation of the proximal fragment. Open reduction and screw fixation were performed, leading to adequate positioning of the 2 bipartite fragments. The patient showed good clinical recovery and returned to the same performance level. Turf toe injury with diastasis of a medial bipartite sesamoid can be treated successfully with this operative technique. Levels of Evidence: Level V: Case report
Article
Hallux valgus deformity is an abnormal aberration of the main metatarsal and parallel aberration of the Hallux (Big Toe), which is mistakenly interpreted as an augmentation of bone or tissue surrounding the Big Toe joint. Objective: The goal of this cross-sectional study was to determine the prevalence of hallux valgus in adults and the variables that cause it. Methods: A sample of 160 young adults (both genders aging b/w 18 to 55 years) was evaluated for hallux valgus using the non-probability purposive sampling technique in Lahore Pakistan. The data were collected through a standardized Bunion Questionnaire and Manchester scale. It took six months to complete, whereas, the data was analyzed using SPSS version 21. Results: For data analysis means, standard deviations were used along with chi-square testing. Adults had a 37.5 percent prevalence of hallux valgus, and the current study indicated that the primary risk variables were growing age, with females suffering more than males. The usage of heels on a regular basis was one of the key risk factors for patients with hallux valgus. Conclusion: The outcomes of the research might lead to improved biomechanical therapies to eliminate needless foot posture loads and the usage of non-ergonomic shoes.
Article
Turf toe injuries have been increasing in numbers in recent years. Injury to the plantar restraints of the first metatarsophalangeal joint can lead to significant disability in athletes, affecting their push-off and ability to perform on the athletic field. Most turf toe injuries can be treated conservatively with rest, ice, compression, immobilization if needed, and a dedicated rehabilitation program; however, in some injuries, the plantar restraints are torn and the joint becomes unstable. If necessary, turf toe injury and its many variants can be surgically repaired with the expectation that the athlete will be able to return to play.
Article
Background We investigated the role of first metatarsal head shape in the etiology of hallux valgus. By pedobarographic analysis, we evaluated whether first metatarsal head shape causes an alteration in plantar pressure values that would result in metatarsalgia. Methods Referrals to our clinic for metatarsalgia, plantar fasciitis, and calcaneal spur were scanned retrospectively. Patients with severe hallux valgus, pes planus, gastrocnemius stiffness, generalized joint laxity, neuromuscular disease, or a history of lower-extremity orthopedic surgery were excluded. Sixty-two patients with plantar pressure assessment and radiographic evaluation were included. These patients were invited for reassessment after 10 years. Feet were divided into three groups by metatarsal head shape: round, square, and chevron. On anteroposterior radiographs, the hallux valgus and intermetatarsal angles, relative first metatarsal length, lateral sesamoid subluxation, and presence of bipartite sesamoid were noted. Plantar pressure was assessed with pedobarography. Results Feet with round-shaped first metatarsal heads had a statistically significantly greater progression in hallux valgus angle than the other shapes. Plantar pressures under the first, second and third, and fourth and fifth metatarsals increased with time. This can explain the mechanism of transfer metatarsalgia and painful callosities under the first metatarsal in hallux valgus. There was no correlation between hallux valgus angle, relative metatarsal length, and lateral sesamoid subluxation. Conclusions We found a strong relation between round-shaped first metatarsal head and hallux valgus angle progression. No patients had a risk factor responsible for hallux valgus. In other words, this study gives approximately 10-year natural history results in nearly normal feet.
Article
A wide variety of pathologies can affect the hallux sesamoid complex of the foot, including traumatic, micro traumatic, degenerative, inflammatory, vascular, infectious, and neoplastic conditions. Symptoms are quite nonspecific, mainly related to pain in the plantar surface of the first metatarsal head. In this context, imaging is important for the etiologic diagnosis of hallux sesamoid complex pathology with implications in patient management. The hallux sesamoid complex has a complex anatomy, and pathologic processes of this region are poorly known of radiologists. Besides, some entities such as “sesamoiditis” remain poorly defined in the literature. Schematically, conditions affecting sesamoids will be divided into two major groups: intrinsic anomalies (sesamoid bone being the center of the pathologic process) and extrinsic anomalies (diseases secondarily involving sesamoid bones). Thus, in this article, after a review of anatomical key points and pathologies affecting the hallux sesamoid complex, a practical multimodality approach for the diagnosis of hallux sesamoid pathologies will be proposed.
Article
Full-text available
Background and Aims: Hallux sesamoid bones forms an integral part of the first metatarsophalangeal joint for stability during weight bearing. Hallux sesamoids are paired bones located on the plantar aspect of the first metatarsal head within the flexor hallucis longus tendon. Hallucal sesamoids vary in shape and size; can be single, double, bipartite and multipartite. Traumatic insult to the hallux sesamoids can lead to fracture & dislocation, while majority of symptomatic hallux sesamoids can be treated non-surgically; certain specific injuries require a high index of suspicion, careful management, and surgical intervention. Hence present study was taken up to know the incidence, presence/absence, number and partition of hallux sesamoid to enlighten the surgeons and radiologists in early diagnosis and treatment of cases presenting with history of trauma, pain and fractures of foot. Methods: Retrospective radiographic study on the incidence, anatomical variants & distribution ofhallux sesamoids inlOOO radiographs ofthe foot. Result: Hallux Sesamoid bones were seen plantar to first metatarsal head in 994 radiographs [99.4%], while the absence ofHallucal sesamoids were noted in 6 radiographs [0.6%], Single Hallucal sesamoid were noted in 9 radiographs [0.9%], medial bipartition was noted in 20 radiographs [2%], lateral bipartition was noted in 15 radiographs [1.5%]. Conclusion: Knowledge regarding hallux sesamoids helps us in differentiating the various conditions arising out of fractures of foot bones with overlapping signs and symptoms, from actual involvement of sesamoid bone itself, which assists in the early diagnosis and management of foot pathologies.
Article
During the past twenty years there have appeared in the literature numerous papers relating to the sesamoid bones of the great toe and their clinical significance. One is impressed, in reading most of these articles, by the uncertainty regarding the embryology, anatomy and function of these small structures, and by the number of disputed points relative to their surgical pathology and treatment. In view of this uncertainty, and because no thorough survey of the literature has appeared, we report this study made in connection with the follow-up investigation of our own cases. Our plan is to review the literature, to cite the results of our own anatomic and pathologic studies and finally to report a series of cases in which sesamoidectomy was performed for the relief of pain. HISTORICAL SUMMARY Not always have the sesamoid bones of the great toe played a rôle of such relative insignificance as they play
Article
A survey of this type cannot be used to point to any definite factor or factors predisposing to the development of hallux valgus. Nevertheless, a comparison of measurements in the morbid and control groups shows several outstanding differences: 1) There was a high degree of correlation between valgus and intermetatarsal angle in the two groups combined (coefficient, 0·7) but the correlation was higher in those cases with a degree of valgus greater than 25 degrees than in the remainder (coefficients, 0·36 and 0·53). 2) In the control group the first metatarsal was longer than tile second by a mean measure of 2 millimetres; in the morbid group by a mean measure of 4 millimetres. For a high degree of valgus and a low intermetatarsal angle the first metatarsal tends to be longer than the second by a significantly greater amount than when the high valgus is associated with iligh intermetatarsal angle. 3) In 90 per cent of the control cases there was a lateral displacement of the medial sesamoid of the first metatarsal of 3 degrees or less, whereas 88 per cent of the morbid group showed a displacement of 4 degrees or more. There was very little overlap in the distributions of this observation in the two groups. There was a high correlation between the degree of this displacement and the severity of hallux valgus. 4) Rotation of the hallux was not observed among the controls; in the morbid group those cases showing rotation had an average degree of valgus of 36 degrees while the rest had an average of 19 degrees. The mean degree of valgus in the morbid group was 32·0 degrees and that of the controls 15·5 degrees. The mean angle between the axes of the first and second metatarsals was 13·0 degrees in the morbid group and 8·5 degrees in the controls. Since tile morbid group consisted largely of women (98 per cent) it is important to know that in the control group the only measure showing a statistically significant sex difference is that of intermetatarsal angle, but that, even so, the mean difference is only 1·3 degrees. Thus tile sex difference between the two groups is probably only of minor importance. The role of age in influencing the observations cannot be clearly elucidated from the data at present available. It can only be stated that there is no positive indication that age is a controlling factor in the departure observed in the morbid group from the control observations.
Article
A retrospective radiographic study was undertaken to determine the incidence of a bipartite tibial sesamoid and its relationship in hallux abducto valgus (HAV) deformity. It was found that the incidence of a bipartite tibial sesamoid associated with HAV deformity was twice as frequent than a bipartite tibial sesamoid in a general foot population. The authors conclude that the tibial sesamoid plays an important role in the development of HAV deformity.
Article
Hallux rigidus is a rather frequent, painful limitation of movements in the metatarsophalangeal joint of the great toe caused by arthrosis. A mechanical limitation of dorsal flexion due to osteophytes frequently causes a progressive plantar flexion with compensatory hypermotility in the interphalangeal joint. Therapeutic measures with technical modification of shoes and physical therapy are often insufficient and operative therapy aims at arthrodesis or remobilisation of the great toe's metatarsophalangeal joint.
Article
The great toe sesamoids have been well reported in the literature, in every aspect. Much has been written about the normal anatomic variation of partite metatarsophalangeal sesamoids. It is the purpose of this article to present a theory explaining the common occurrence of a symptomatic partite sesamoid. The authors believe there is a high rate of occurrence of symptomatic partite sesamoids, especially when associated with hallux abducto valgus. Presented is information concerning the internal and external structural components of a bipartite metatarsal sesamoidal joint, which may inherently lead it to symptomatology.
Article
In 25 normal subjects and 10 patients with mild 'idiopathic' hallux valgus, electromyographic investigations revealed muscle imbalance between adductor and abductor muscles in the development of the deformity. Muscle imbalance becomes worse in time with stresses of weight bearing. Whether the muscle imbalance is a primary cause or a secondary result of the deformity is not clear. In hallux valgus, adductor hallucis muscle is markedly weak, but abductor hallucis muscle loses the abductor's function completely and works only as a flexor. Flexor hallucis brevis also loses some of its function as a flexor because its tendon stretches and moves plantarwards as a result of mechanical malalignments. At the MP joint of the great toe, the adductor force is relatively stronger than it is in normals because there is total loss of abductor force.