stress fractures occur due to repetetive loading of the bones with submaximal stress rather 
 than a single traumatic event .
they can occur in all bones of the lower extremity , 
 particularly in people predisposed to repetetive strain , such as athletes .
any sports 
 involving repetitive jumping , cutting , landing , long distance running , tennis , basketball 
 may predispose the athlete to stress fractures .
the incidence increases with a sudden 
 increase in intensity or duration of training , poor physical conditioning , or incorrect 
 footwear .
excessive forefoot or ankle varus , leg length discrepancy , a high or low 
 longitudinal arch , muscle imbalance and tightness are other risk factors . in women , repeated 
 stress , low bone mineral density and dietary restraint have been reported as a specific risk 
 triad1 .
vitamin k promotes clotting and is involved in the activation of important proteins in 
 blood coagulation , prothrombin ( ii ) , factor vii , factor ix , and factor x , as well as protein 
 c and protein s. deficiency of these factors can result in defective clotting and a bleeding 
 disorder .
when vitamin k was discovered , it was believed to have only the role of supporting 
 coagulation , and it was given the name 
because of low plasma concentration , vitamin k has been 
 assessed by functional methods , using prothrombin time to determine its effect on clotting 
 time .
further research has shown that it also functions as a coenzyme that enhances calcium 
 incorporation into bone .
the currently known forms of vitamin k can be grouped into the 
 following three categories : vitamin k1 ( phytomenadione or phytomenadione ) , vitamin k2 
 ( menaoquinones ) , and vitamin k3 ( menadione ) . vitamins k1 and k3 are fat - soluble , whereas 
 vitamin k2 is water - soluble .
technically , only vitamin k1 is recognized as a true vitamin , 
 which is essential for human and animal well - being and present in fresh green vegetables 
 such as broccoli , cabbage , lettuce , and spinach .
vitamins k2 and k3 can be derived as 
 metabolites of vitamin k1 in various tissues or the gastrointestinal tract in animals or 
 humans . it has been shown that vitamin k2 modulates the genetic expression of collagen type 
 1 and osteocalcin which leads to increased produciton of these proteins by osteoblasts3 .
its reducing effect on osteoblasts 
 apoptosis4 and stimulating effect on 
 other bone blastic proteins , such as osteoprotegerin and osteopontin5 , have been reported . regarding bone remodelling resorption , 
 the reduction of osteoclast production from bone marrow cells6 and induction of osteoclasts apoptosis
these 
 metabolic effects are achieved through vitamin k2 s ability to downregulate inflammation 
 ( il-6 , pge2 ) and cell proliferation while increasing apoptosis7 .
it should be emphasized that this would be effective only if 
 osteoclastic activity is excessively high .
vitamin k2 may reduce the accelerated bone 
 resorption induced by menopausal hormonal loss8 or corticosteroid treatment9 , 
 10 .
vitamin k deficiency as a possible 
 contributing factor for stress fractures has not been described before , although there are 
 reports documenting its effect on osteoporotic femoral neck fractures .
a 13-year - old basketball player was admitted complaining of right foot pain for the 
 previous 5 days .
he had 
 no remarkable medical history , except for a deficiency of vitamin k when he was 3 or 4  years 
 old .
he never had any bleeding disorder and the parents did not remember why vitamin k level 
 was checked . he had been playing basketball since he was 10  years old .
his practices were 
 1.5 to 2 hours / day , 5 days a week .
he reported no recent increase in the intensity or 
 duration of the training sessions .
he did not have pain during normal activities of daily 
 living , but he was unable to practice because of pain .
physical examination findings were tenderness of the plantar fascia and lateral 
 side of the ankle with palpation , low medial longitudinal arches , and tight hamstrings and 
 achilles tendons .
magnetic resonance imaging showed edema of the cuboid and third cuneiform 
 bones , together with mild effusion of the surrounding soft tissues .
tendonitis of the flexor 
 hallucis and digitorum longi were also present ( fig . 

1.magnetic resonance imaging ( mri ) findings of the 
 patient on admission showing edema of the cuboid and third cuneiform bones , mild 
 effusion of the surrounding soft tissues , tendonitis of the flexor hallucis and 
 digitorum longi ) .
the 
 foot was immobilized for 4 weeks and he received physiotherapy consisting of electrical 
 stimulation ( both tens for pain relief and muscle stimulation for strengthening ) and 
 hydrotherapy during this time .
his normal activities of daily living were allowed with the 
 immobilized foot . between the 4th and 6th weeks , he reported about 80% improvement of 
 symptoms and partial weight bearing was allowed .
he had only mild tenderness of the plantar 
 fascia on palpation . at the end of the 6th week , he reported diffuse and more severe pain . 

diffuse tenderness on the dorsal and 
 plantar surfaces of the foot was evident and ankle movements were painful and limited . 

updated imaging was ordered and showed increased areas of edema of both the cuboid and the 
 third cuneiform bones and surrounding soft tissues when compared with the first imaging . 

there was also edema of the talar bone on the navicular side and the proximal first 
 metatarsal bone which had not been present prior .
2.magnetic resonance imaging ( mri ) findings of the patient at 6th 
 week showing increased areas of edema of both the cuboid and the third cuneiform bones 
 and surrounding soft tissues , edema of the talar bone on the navicular side and the 
 proximal first metatarsal bone , tenosynovitis of the flexor hallucis and digitorum 
 longi ) .
the test results were as follows ( nr , 
 normal range):hb : 11.5  g / dl ( nr : 1116 ) , erythrocyte sedimentation rate ( esr ) : 33  mm / h ( nr : 
 < 15 ) , c - reactive protein ( crp ) : 1.75  mg / dl ( nr : < 0.22 ) , rheumatoid factor ( rf ) : 8 iu/ 
 ml ( nr : < 14 ) , antinuclear antibody ( ana ) : negative , fasting blood sugar : 104  mg / dl ( nr : 
 70100 ) , calcium : 10  mg / dl ( nr : 9.210.7 ) , phosphorus : 4.6  mg / dl ( nr : 3.15.3 ) , alkaline 
 phosphatase ( alp ) : 263 u / l ( nr : 169618 ) , parathormone ( pth ) : 38  pg / ml ( nr : 1472 ) , vitamin 
 d , 25 hydroxy : 28.2 ng / ml ( nr : 2580 ) , vitamin b12 : 592 pg / ml ( nr : 200835 ) , blood urea 
 nitrogen ( bun ) : 9  mg / dl ( nr : 4.6722.43 ) , creatinine : 0.79  mg / dl ( nr : 0.51.1 ) , alt : 22 u / l 
 ( nr : 1659 ) , ast : 18 u / l ( nr : 1036 ) .   magnetic resonance imaging ( mri ) findings of the 
 patient on admission showing edema of the cuboid and third cuneiform bones , mild 
 effusion of the surrounding soft tissues , tendonitis of the flexor hallucis and 
 digitorum longi magnetic resonance imaging ( mri ) findings of the patient at 6th 
 week showing increased areas of edema of both the cuboid and the third cuneiform bones 
 and surrounding soft tissues , edema of the talar bone on the navicular side and the 
 proximal first metatarsal bone , tenosynovitis of the flexor hallucis and digitorum 
 longi although not routinely ordered in practice , as the parents reported a nonspecific history , 
 and the other findings did not explain the clinical situation , serum vitamin k level was 
 ordered , with the result < 0.1 ng / ml ( nr : 0.122 ) . at the time of blood sampling for 
 vitamin k testing , fasting blood sugar test was repeated because of the above - normal range 
 during the first test ; the result was 88  mg / dl .
dietary habits were also questioned ; an 
 exact food diary could not be obtained , but his parents stated that he had fresh green 
 vegetables like broccoli and lettuce on an average of 3 to 4 times per week .
overall , his 
 diet was quite balanced , with consumption of lean meat or fish , dairy products , citrus 
 fruits on a daily basis .
his foot was immobilized for an additional 2 weeks , and partial weight bearing was then 
 allowed . during the total and partial non - weight bearing periods , he performed isometric 
 exercise and hamstring and achilles stretches .
he was encouraged to consume more fresh green 
 vegetables for at least one meal per day . following 5 months from the beginning of the 
 symptoms ,
he started practicing with longitudinal arch supports ; he started participating in 
 games at the 6th month .
stress fractures of the lower extremities are common in athletes and they are being more 
 commonly diagnosed both by increased awareness of the physicians and by imaging techniques . 

gait , limb 
 length discrepancy , and tightness of the proximal muscles and tendons should be noted in the 
 physical examination as well as the general appearance of the foot regarding shape , 
 deformity , swelling , pain and tenderness , and range of motion . the present case exhibited 
 low medial longitudinal arches and tight hamstrings as well as short achilles tendons ; these 
 were all predisposing factors for stress fractures .
these factors were appropriately 
 corrected during the treatment process and after the patient returned to sport . in general
, 
 the severity of the fracture and pain can dictate how soon an athlete can re initiate 
 regular training . in this case , the initial expectation was to restart training with a 
 gradual increase in intensity after 6 weeks however , this was no achieved in our case .
a 
 second magnetic resonance imaging was ordered as the patient s symptoms and physical 
 examination findings progressed despite treatment .
although this case was not bilateral , as the condition progressed , 
 these issues were considered .
esr and crp were elevated ; this was not unexpected as there was an inflammatory 
 reaction in the body .
it was 
 rechecked in the same sample extracted to test vitamin k level , and shown to be within the 
 normal range .
serum vitamin k level is not routinely checked as it is found in very low 
 concentrations in the serum ; instead , prothrombin time is used to determine its effect on 
 clotting time .
the patient had no history of any bleeding disorder , including no excessive 
 bleeding after circumcision .
the parents did not recall the patient s previous history of 
 serum vitamin k level .
although the previous test results were unavailable , it was reported 
 to be low .
they had not been advised to take any action on the situation . after finding the 
 level to be lower than normal limits
, we investigated his dietary habits , as vitamin k is 
 found in green leafy vegetables such as spinach , broccoli , lettuce , and others .
our patient 
 had some of these vegetables as part of his diet , but like many of teenagers of his age , he 
 was not motivated to consume them .
poor vitamin k staus is reported to be associated with 
 low bone mass , osteoporosis , and fracture risk in adults12,13,14 , but its relationship with stress fractures has not been reported . 

considering the effects of vitamin k on osteocalcin , it was concluded that the vitamin k 
 requirement of children is much larger than that of adults because osteocalcin synthesis is 
 at least 10-fold higher during growth than after peak bone mass has been reached15 . in an epidemiological study investigating 

the association of hip fracture incidence and intake of calcium , magnesium , vitamin d , and 
 vitamin k in japan , a striking pattern of high intake of vitamin k and low incidence of hip 
 fractures in eastern areas of japan was apparent , with the opposite pattern  a low intake of 
 vegetables rich in vitamin k and a high incidence of hip fracture  in western areas16 .
the observers found significant inverse 
 associations between hip fracture incidence and each nutrient , but after adjusting for 
 covariates , the strongest correlation was seen with vitamin k. the effects of calcium and vitamin d on bone metabolism are very well known with no doubt 
 that individuals should have adequate intake through diet and/or supplements .
the need is 
 increased in certain conditions like adolescence , pregnancy , and post - menapausal states . 

calcium and vitamin d deficiency may lead to both osteoporotic fractures and stress 
 fractures .
the deficiency of vitamin k , apart from its effects on bleeding , has been linked 
 with osteoporotic fractures ; however , it has not currently been related to the poor healing 
 of stress fractures . in the present case
, there were clear risk factors such as repetitive 
 loading with poor mechanics resulting from low medial longitudinal arches , tight hamstrings , 
 and achilles tendons .
however , although measures to treat the condition were taken , the 
 progress was not as expected , and progressively worsened . assessing serum vitamin k level 

was not initially planned until the parents reported that a previous history was present . 
 the patient s eating habits were like most of the adolescents of his age , but he was not 
 very strict on eating no vegetables .
he cooperated when he was encouraged to increase the 
 amount of green vegetables in his diet .
the present case can not be directly related to vitamin k deficiency alone , and , as 
 mentioned above , an unhealing stress fracture due to vitamin k deficiency has not been 
 reported previously .
the patient returned to full sport activities at the 6th month , which 
 is the approximate time period to be expected with many types of stress fracures .
thus , a 
 claim that increasing the amount of green vegetables in his diet necessarily improved the 
 situation is unfounded .
additionally , a follow - up vitamin k level assessment was not 
 performed and it is not known whether the level reached normal limits after the dietary 
 changes . in conclusion , along with assessing calcium and vitamin d status , which has a very 
 well - documented effect on bone metabolism , we advise questioning on consumption of green 
 vegetables to gain a full picture on the potential vitamin k level in patients with stress 
 fractures , especially if healing does not occur as expected . if a poor status is confirmed , 
 encouraging the patient to consume green vegetables in at least one meal a day might assist 
 in the healing process .
it is not recommended to examine serum vitamin k levels in patients 
 with stress fractures on a routine basis .
 [ purpose ] to report an adolescent male basketball player with nonhealing stress fractures 
 of the foot and discuss the probable factors . [ subject and methods ] a 13-year - old 
 basketball player presented with right foot pain . 
 he had been playing basketball for three 
 years and practicing 5 days / week . 
 he denied any increase in daily training intensity . 
 
 magnetic resonance imaging confirmed stress fractures of the cuboid and cuneiform , with 
 mild edema of the soft tissues between the tarsal bones and tenosynovitis of the flexor 
 hallucis and flexor digitorum longi . 
 the foot was immobilized for 4 weeks , with 
 progressive weight bearing introduced at the fifth week . at the 6th week , while still 
 restricted to partial weight bearing , he reported diffuse severe pain . 
 the entire foot was 
 painful with palpation , and new imaging showed stress fractures of the talus , cuboid , 
 cuneiform , and proximal first metatarsal bones , and tenosynovitis of the flexor hallucis 
 longus and flexor digitorum longus tendons with progression of the soft tissue edema 
 around the tarsal bones . 
 acute phase reactants were elevated ; vitamin k level was low . 
 
 [ results ] he started participating in games again at the 6th month post - injury . 
 
 [ conclusion ] management of patients with stress fractures includes immobilization , 
 physical therapy , and biomechanical arrangements . 
 if the expected healing does not occur , 
 a deficiency of vitamin k might be considered as a factor . 
 questioning on dietary habits 
 of the patient and encouraging adequate intake of the deficient nutrient might assist in 
 the healing process . 
INTRODUCTION
SUBJECT AND METHODS
RESULTS
DISCUSSION