AUTHOR AND EDITOR INFORMATION

Section 1 of 11  

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• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Multimedia
• References

INTRODUCTION

Section 2 of 11  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Multimedia
• References

Background

Stress fractures are a common problem in various populations, including runners and military trainees.^{1, 2, 3} These fractures can occur with as little as 2-3 weeks of training, be very mild, and cause only minimal changes to the bone, which eventually heals, or they may progress to a complete fracture that requires surgical fixation. Although rare, poor outcomes may occur in the form of nonunions or avascular necrosis. Certain stress fractures have a higher risk of poor outcome, including anterior tibial and femoral neck stress fractures (FNSFs). 

(See also the eMedicine articles Femoral Head Avascular Necrosis [in the Sports Medicine section], Avascular Necrosis, Femoral Head and Stress Fracture [in the Radiology section], and Stress Fracture [in the Physical Medicine and Rehabilitation section], as well as Risk Factors for Bone tress Injuries: A Follow-up Study of 102,515 Person-Years and Total Hip Arthroplasty in the Older Population on Medscape.)

FNSFs are some of the most difficult injuries to diagnose. The pain associated with such an injury may be poorly localized in the hip and may be referred to the thigh or back. Physical examination findings are not very specific for this injury, and diagnostic radiographs in the form of x-ray films, bone scans, and/or magnetic resonance images (MRIs) are often necessary.⁴ Failure to diagnose FSNFs may lead to catastrophic consequences, including avascular necrosis of the femoral head and the need for a hip replacement in otherwise healthy young individuals.^{5, 6, 7} A high index of suspicion in the appropriate risk populations is the key to diagnosing and treating FNSFs.

(See also the eMedicine article Femoral Neck Stress and Insufficiency Fractures.) 

For excellent patient education resources, visit eMedicine's Foot, Ankle, Knee, and Hip Center; Breaks, Fractures, and Dislocations Center; and Sports Injury Center. Also, see eMedicine's patient education articles Broken Leg and Total Hip Replacement.

Frequency

United States

Stress fractures may develop in up to 15% of runners and military trainees.³ Of those patients who develop stress fractures, about 5-10% of the fractures are in the femoral neck.⁸ Stress fractures on the compression side (the inferior aspect) of the femoral neck are more common than stress fractures on the tension side (the superior aspect).

Functional Anatomy

The femoral neck lies between the femoral head and femoral shaft, demarcated by the greater and lesser trochanters. Weight-bearing forces from the trunk cause a compressive force on the inferior aspect of the femoral neck, whereas the superior aspect is subject to tensile forces.^{6, 9} The blood supply to the femoral head runs through the femoral neck; thus, an FNSF may disrupt the blood supply to the femoral head and cause avascular necrosis of the femoral head.⁶

Sport-Specific Biomechanics

The load of the runner's body weight is transmitted down the lower extremities through the bones and may exceed 3-5 times the body weight in the femoral neck during running. Muscles help to absorb forces and distribute load, especially the gluteus medius. The weight of the trunk and upper extremities applies compressive forces to the inferior aspect of the femoral neck. Conversely, tensile forces act upon the superior aspect of the femoral neck. These forces become important in the prognosis and management of the stress fracture. A sudden reduction in weight and lower muscle mass combined with daily training was associated with an increased risk of FNSF in US Naval Academy plebes.³

CLINICAL

Section 3 of 11  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Multimedia
• References

History

• Runners and military trainees develop stress fractures as the duration, frequency, and intensity of weight-bearing activities is increased. Furthermore, changes in running surfaces, such as from a flat surface to hills, or carrying a pack may increase the risk of stress fractures.
• The patient reports a gradually worsening deep, achy pain in the hip, groin, or thigh.
• Usually, pain initially occurs after an activity. As the stress of training continues, pain occurs during training and becomes more intense.
• Unless the form of the activity is modified, the pain gradually worsens over a few weeks to the point where the patient is unable to walk without pain.
• Continued activity will probably result in completion of the stress fracture.

Physical

• Physical examination reveals the patient to have an antalgic gait.
• Unlike many other stress fractures, it is not possible to palpate the femoral neck and determine the presence of the usual bony tenderness of a stress fracture. However, hip palpation may suggest another diagnosis, such as a hip flexor strain, if pain is present at the anterior inferior iliac spine and upon hip flexion. Other possible diagnoses include greater trochanteric bursitis, adductor strain, or a pubic ramus stress fracture. (See also the eMedicine articles Trochanteric Bursitis [in the Sports Medicine section], Adductor Strain [in the Physical Rehabilitation and Medicine section], and Pelvic Fractures [in the Orthopedic Surgery section].)
• Pain at the extremes of passive range of motion (ROM), especially external and internal rotation, is the most sensitive sign for stress fractures.
• Pain that is associated with log rolling, axially loading a supine patient (heel tap), and with single-leg standing or hopping also suggests a stress fracture. (Note: Performing a single-leg hopping test in a patient with a potential FNSF is risky and may cause completion of the stress fracture; this practice is not advised.)

Causes

• Improper training is the most obvious cause for a stress fracture.
• • Increasing the duration, frequency, and/or intensity of training too quickly does not allow for proper bone and supporting muscle adaptation, resulting in microscopic damage to the bone, which cannot be healed quickly.
• In the military population, trainees who have initially lower levels of fitness and higher body mass indexes are at an increased risk of stress fractures.¹ A history of a previous stress fracture is also a risk factor for a recurrence. In addition, coxa vara has been associated with an increased risk of FNSF.¹⁰
• Other hypothesized risk factors for FNSF include improper footwear, leg-length discrepancies, and a change of the running surface.
• Females with the female athlete triad (ie, disordered eating, menstrual dysfunction, premature osteoporosis) are also at increased risk for stress fractures. (See also the eMedicine article Female Athlete Triad.)
• Young women who exercise regularly can increase the bone density of their femoral neck.
• Plebes undergoing training at the US Naval Academy who had significant weight loss and smaller muscle mass were associated with a much higher incidence of stress fracture than their fitness-matched cohorts.³

DIFFERENTIALS

Section 4 of 11  

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• Follow-up
• Miscellaneous
• Multimedia
• References

Other Problems to Be Considered

Avascular Necrosis, Femoral Head

Bone tumors

Degenerative arthritis

Hip capsulitis and synovitis

Inflammatory arthropathy

Legg-Calve-Perthes Disease (in the Radiology section) (See also Legg-Calve-Perthes Disease [in the Emergency Medicine section] and Legg-Calve-Perthes Disease [in the Orthopedic Surgery section].)

Rectus femoris tendonitis

Referred pain from a herniated disk in the lower back

Septic hip

Slipped Capital Femoral Epiphysis (in children)

Trochanteric Bursitis

WORKUP

Section 5 of 11  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Multimedia
• References

Lab Studies

• Consider laboratory studies with a complete blood cell (CBC) count and erythrocyte sedimentation rate (ESR) if infection, inflammatory arthropathy, or a tumor is suspected.

Imaging Studies

• X-ray films
• • Obtain anteroposterior and frog-leg views.
  • Obtain appropriate radiographs if femoral shaft or pubic ramus fractures are suspected. (See also the eMedicine article Femur Injuries and Fractures.)
  • If the initial radiographs are negative (and they often are), and the suspicion for FNSF is high based on the patient history and physical examination, obtain a bone scan or MRI.⁴ Instruct the patient to remain non-weight bearing on crutches until the study is obtained.
  • If the patient's symptoms are mild, or bone scanning or MRI is unavailable, the patient should be on crutches, non-weight bearing or touchdown weight bearing, until the bone scan/MRI is obtained or repeat films in 2 weeks are negative.
• MRI yields more diagnostic information than bone scanning and is especially more useful in difficult cases.⁴

Other Tests

• Other tests, such as hip joint aspiration for a septic joint, are only indicated if the clinician is considering alternative diagnoses.

TREATMENT

Section 6 of 11  

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• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Multimedia
• References

Acute Phase

Rehabilitation Program

Physical Therapy

Follow the acute treatment principles of protection, rest, ice, compression, elevation, medication, and modalities (PRICEMM). This treatment regimen is most appropriate for compression (as opposed to tension) fractures. Patient compliance is important.

• Protection – Crutches with non–weight-bearing ambulation until relief of pain at rest is achieved
• Rest – Non-weight bearing if there is pain at rest; may do alternative exercises to maintain cardiovascular conditioning (eg, swim, upper-extremity Exercycle [Exercycle Company, Franklin, Mass])
• Ice – To assist with pain reduction
• Elevation – Usually difficult
• Medication – Consider low-dose nonsteroidal anti-inflammatory drugs (NSAIDs) for pain relief or narcotics, if the patient has severe pain.
• Modalities – Not much help acutely

Medical Issues/Complications

If the stress fracture is on the compression side of the femoral neck and if the fracture is not displaced, patients usually do well with conservative management (non-weight bearing on crutches), with a gradual progression to touchdown weight bearing, partial weight bearing, then to no crutches in 4-6 weeks, depending upon the clinical response.

Tension-side fracture treatment is somewhat controversial, with some physicians advocating surgical pinning (even for nondisplaced fractures) and others advocating conservative treatment such as for compression-side fractures. In a compliant patient who will maintain non-weight bearing on crutches, a trial of conservative treatment with non-weight bearing on crutches is recommended for both types of fractures unless displacement is present, in which case, urgent referral for operative evaluation and fixation is indicated.

Treatment of the tension-side stress fracture is based on the completeness of the fracture (ie, unicortical vs bicortical), which, in turn is, based on a classification scheme. In general, bicortical tension-side fractures are treated surgically.

Surgical Intervention

Surgical intervention is dependent upon the type of fracture. Compression-side fractures can be treated with conservative therapy. Nondisplaced tension-side treatment is controversial, with some physicians advocating prophylactic surgical fixation and others advocating a trial of conservative therapy in compliant patients. Urgently refer the patient for orthopedic evaluation for surgical fixation in cases with displaced fractures.

Consultations

Regardless of the presence or absence of fracture displacement, tension-side stress fractures of the femoral neck should be managed in coordination with an orthopedic specialist.

Other Treatment

Review the patient's diet; ensure adequate calcium and vitamin D intake, and supplement as needed. Consider oral contraceptives for amenorrheic women; such agents may aid in the recovery of bone mass in these women. Athletes with eating disorders may need psychologic and nutritional support.

Recovery Phase

Rehabilitation Program

Physical Therapy

As the patient’s pain decreases, gradually increase activity from non-weight bearing to touchdown weight bearing, then to partial weight bearing, and eventually, discontinuation of the crutches. This process usually takes 4-6 weeks. Coordinate the patient's rehabilitation with the orthopedic specialists for those individuals who have hips with surgical pinning. After the patient is able to walk 1.5 miles without pain (usually in 8-12 wk, but sometimes longer), begin a gradual return to a running program. Usually, it takes approximately 2.5 months to be able to run 3 miles pain free. If pain returns during the rehabilitation period, decrease the patient's activity until walking is pain free again.

Non–weight-bearing training can also play a role in the patient's rehabilitation. Activities such as running in water with an appropriate floatation vest can be helpful. Upper-extremity resistance exercises and aerobic training can also be used.

Medical Issues/Complications

A very mild pain may return briefly when the patient first attempts to run. If the pain is more than a very mild intensity, the stress fracture may not have healed completely yet and needs additional rest. If the patient's pain is severe, obtain another x-ray to check for displacement. Avascular necrosis, nonunion, malunion, and eventual hip replacement may result from complications of an FNSF that is not diagnosed in time or that is rehabilitated too quickly.

Surgical Intervention

If the patient's pain persists for longer than 2 weeks—despite true compliance with non–weight-bearing status on a tension-side, nondisplaced stress fracture—consider surgical fixation, if the procedure has not already been performed.

Consultations

Consult an orthopedic specialist if the patient's rehabilitation for an FSNF is not progressing adequately.

Other Treatment (Injection, manipulation, etc.)

Ensure the patient has an adequate calcium and vitamin D intake. If an eating disorder is present, monitor the patient's treatment and help the patient recover proper dietary and weight-management habits.

Maintenance Phase

Rehabilitation Program

Physical Therapy

Monitor the patient's activity to ensure that the same training errors that initially resulted in the stress fracture are not committed again. Gradual increases in mileage (£10%/wk) are generally accepted as safe and effective. Likewise, the intensity of the patient's workouts should increase gradually, not dramatically.

Medical Issues/Complications

If the same type of pain reappears despite therapy, the patient should return to the clinician to check for a recurrent stress fracture.

Surgical Intervention

If the femoral neck was surgically fixed, consult the orthopedic specialist regarding when (if ever) the pins should be removed.

Consultations

Obtain an orthopedic consultation if the patient's recovery is not progressing adequately.

Other Treatment

The patient should continue calcium supplementation, if necessary. Monitor for recurrence of an eating disorder, if appropriate.

MEDICATION

Section 7 of 11  

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The goals of pharmacotherapy are to reduce morbidity and to prevent complications in patients with FNSFs.

Drug Category: Mineral supplements

Calcium supplementation may be necessary for patients with FNSFs. The average daily recommendations for children aged 9-18 years is 1300 mg of calcium daily. Individuals aged 19-50 years and postmenopausal women should have a daily calcium intake of 1000 mg of calcium. Middle-aged women and males 50 years and older should receive 1200 mg of calcium daily. Vitamin D supplementation may also be necessary.

Drug Name	Calcium citrate (Citracal)
Description	Moderates nerve and muscle performance by regulating the action potential excitation threshold. Give the amount that is needed to supplement an individual's diet to reach the recommended daily amounts.
Adult Dose	200 mg PO qd
Pediatric Dose	Not established
Contraindications	Renal calculi, hypercalcemia, hypophosphatemia, renal or cardiac disease, patients with digitalis toxicity
Interactions	May decrease the effects of tetracyclines, atenolol, salicylates, iron salts, and fluoroquinolones; IV administration antagonizes the effects of verapamil; large intakes of dietary fiber may decrease calcium absorption and levels
Pregnancy	A - Fetal risk not revealed in controlled studies in humans
Precautions	Caution in digitalized patients and in the presence of respiratory failure or acidosis

Drug Category: Nonsteroidal anti-inflammatory drugs

NSAIDs have analgesic, anti-inflammatory, and antipyretic activities. The mechanism of action of these agents is not known, but they may inhibit cyclooxygenase activity and prostaglandin synthesis. Other mechanisms may exist as well, such as inhibition of leukotriene synthesis, lysosomal enzyme release, lipoxygenase activity, neutrophil aggregation, and various cell membrane functions. Many NSAIDs are currently on the market. There is no evidence to support that one agent is more efficacious than another; however, individual response may differ.

The routine use of NSAIDs for treating stress fractures has been called into question because these drugs have been shown to slow bone formation and may mask the pain that serves as a guide for the timing of advancing rehabilitation.¹¹ Therefore, administer NSAIDs sparingly for initial pain, if at all. Furthermore, with the other complications of NSAIDs (eg, gastrointestinal [GI] bleeding) and the known difficulties with COX-2 inhibitors, caution is advised.

Drug Name	Naproxen (Aleve, Naprelan, Naprosyn, Anaprox)
Description	For relief of mild to moderate pain; inhibits inflammatory reactions and pain by decreasing the activity of cyclooxygenase, which results in a decrease of prostaglandin synthesis. May slow bone healing, so use sparingly.
Adult Dose	500 mg PO followed by 250 mg PO q6-8h; not to exceed 1.25 g/d
Pediatric Dose	<2 years: Not established >2 years: 2.5 mg/kg/dose PO; not to exceed 10 mg/kg/d
Contraindications	Documented hypersensitivity; peptic ulcer disease; recent GI bleeding or perforation; renal insufficiency
Interactions	Coadministration with aspirin increases the risk of inducing serious NSAID-related side effects; probenecid may increase the concentrations and, possibly, the toxicity of NSAIDs; may decrease the effect of hydralazine, captopril, and beta-blockers; may decrease the diuretic effects of furosemide and thiazides; may increase PT duration when taking anticoagulants (instruct patients to watch for signs of bleeding); may increase the risk of methotrexate toxicity; phenytoin levels may be increased when administered concurrently
Pregnancy	B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals
Precautions	Category D in third trimester of pregnancy; acute renal insufficiency, interstitial nephritis, hyperkalemia, hyponatremia, and renal papillary necrosis may occur; patients with preexisting renal disease or compromised renal perfusion risk acute renal failure; leukopenia occurs rarely, is transient, and usually returns to normal during therapy; persistent leukopenia, granulocytopenia, or thrombocytopenia warrants further evaluation and may require discontinuation of drug

Drug Name	Ketoprofen (Actron, Orudis, Oruvail)
Description	For relief of mild to moderate pain and inflammation. Small dosages are initially indicated in small and elderly patients and in those with renal or liver disease. Doses over 75 mg do not increase therapeutic effects. Administer high doses with caution, and closely observe patient for response. May slow bone healing, so use sparingly.
Adult Dose	25-50 mg PO q6-8h prn; not to exceed 300 mg/d
Pediatric Dose	<3 months: Not established 3 months to 12 years: 0.1-1 mg/kg PO q6-8h >12 years: Administer as in adults
Contraindications	Documented hypersensitivity
Interactions	Coadministration with aspirin increases the risk of inducing serious NSAID-related side effects; probenecid may increase the concentrations and, possibly, the toxicity of NSAIDs; may decrease the effect of hydralazine, captopril, and beta-blockers; may decrease the diuretic effects of furosemide and thiazides; may increase PT duration when taking anticoagulants (instruct patients to watch for signs of bleeding); may increase the risk of methotrexate toxicity; phenytoin levels may be increased when administered concurrently
Pregnancy	B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals
Precautions	Category D in third trimester of pregnancy; caution in patients with congestive heart failure, hypertension, and decreased renal and hepatic function; caution in the presence of coagulation abnormalities or during anticoagulant therapy

FOLLOW-UP

Section 8 of 11  

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• Follow-up
• Miscellaneous
• Multimedia
• References

Return to Play

Once the athlete has completed the walk/run rehabilitation program and is able to run 3 miles without pain, gradually increase the mileage (no more than 10% per wk) until the goal level is obtained. Gradual sport-specific drills and higher-intensity training should be accomplished over a few weeks.

Complications

Complications of FNSFs include recurrence of the stress fracture and avascular necrosis of the femoral head.

Prevention

Prevention of FNSFs includes gradually increasing the intensity and duration of training; halting/decreasing training upon return of symptoms; and reevaluating the patient for stress fracture recurrence, adequate calcium intake, and further treatment of an eating disorder (if appropriate).

Prognosis

Compression-side fractures have an excellent prognosis. Usually, if the injury is diagnosed early and the patient does not return to training too rapidly, tension-side fractures also do well. However, up to 25% of patients may have residual hip pain, discomfort, and gait problems 5-7 years after treatment.

Displaced fractures have a guarded prognosis until after surgical fixation, and then the patients undergo evaluation for another 4-6 weeks. Even after surgical fixation, displaced FNSFs have a high prevalence of avascular necrosis, with one case series reporting a rate of 24%.⁶ The authors reported persistent pain and a poor outcome occurred in 19% of the 42 patients.

MISCELLANEOUS

Section 9 of 11  

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• Follow-up
• Miscellaneous
• Multimedia
• References

Medical/Legal Pitfalls

• FNSFs are difficult to diagnose; however, the patient's history and physical examination findings that are indicative of pain upon internal and/or external rotation of the hip or pain upon single-leg standing or hopping should arouse clinical suspicion of an FNSF. (Note: Single-leg hopping may complete the fracture and should be discouraged.)

  The patient should be restricted to crutches, non-weight bearing, or touchdown weight bearing, if it causes no pain. Perform further investigation, including radiography, bone scanning, and/or MRI. A missed FSNF that was originally diagnosed as bursitis or tendonitis—thus allowing the patient to return to sports, only to have the patient snap the femoral neck and eventually require an artificial hip—is not a good outcome. A completed displaced FNSF has about a 20% chance of having a poor outcome even with surgical fixation; thus, diagnosing these injuries before completion of the fracture is essential.

MULTIMEDIA

Section 10 of 11  

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• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Multimedia
• References

Media file 1:  Radiograph showing a tension-side, completed femoral neck stress fracture.
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Media type:  X-RAY

Media file 2:  Radiograph showing sclerosis on the compression side of the femoral neck.
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Media type:  X-RAY

Media file 3:  Radiograph are often initially negative for stress fractures, including femoral neck stress fractures. Repeating x-ray films in 2 weeks may show the changes of a stress fracture, but approximately 20% of cases do not. Bone scanning or magnetic resonance imaging may be necessary to rule out a stress fracture. In the x-ray film for this patient, no changes were seen, but a bone scan showed an obvious compression stress fracture of the right femoral neck.
	View Full Size Image
Media type:  Nuclear Image

REFERENCES

Section 11 of 11

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Multimedia
• References

1. Shaffer RA, Rauh MJ, Brodine SK, Trone DW, Macera CA. Predictors of stress fracture susceptibility in young female recruits. Am J Sports Med. Jan 2006;34(1):108-15. [Medline]. [Full Text].
2. DeFranco MJ, Recht M, Schils J, Parker RD. Stress fractures of the femur in athletes. Clin Sports Med. Jan 2006;25(1):89-103, ix. [Medline].
3. Armstrong DW 3rd, Rue JP, Wilckens JH, Frassica FJ. Stress fracture injury in young military men and women. Bone. Sep 2004;35(3):806-16. [Medline].
4. Shin AY, Gillingham BL. Fatigue fractures of the femoral neck in athletes. J Am Acad Orthop Surg. Nov 1997;5(6):293-302. [Medline].
5. Weistroffer JK, Muldoon MP, Duncan DD, Fletcher EH, Padgett DE. Femoral neck stress fractures: outcome analysis at minimum five-year follow-up. J Orthop Trauma. May 2003;17(5):334-7. [Medline].
6. Lee CH, Huang GS, Chao KH, Jean JL, Wu SS. Surgical treatment of displaced stress fractures of the femoral neck in military recruits: a report of 42 cases. Arch Orthop Trauma Surg. Dec 2003;123(10):527-33. [Medline].
7. Pihlajamäki HK, Ruohola JP, Kiuru MJ, Visuri TI. Displaced femoral neck fatigue fractures in military recruits. J Bone Joint Surg Am. Sep 2006;88(9):1989-97. [Medline].
8. Egol KA, Koval KJ, Kummer F, Frankel VH. Stress fractures of the femoral neck. Clin Orthop Relat Res. Mar 1998;348:72-8. [Medline].
9. Jones BH, Harris JM, Vinh TN, Rubin C. Exercise-induced stress fractures and stress reactions of bone: epidemiology, etiology, and classification. Exerc Sport Sci Rev. 1989;17(1):379-422. [Medline].
10. Carpintero P, Leon F, Zafra M, et al. Stress fractures of the femoral neck and coxa vara. Arch Orthop Trauma Surg. Jul 2003;123(6):273-7. [Medline].
11. Stovitz SD, Arendt EA. NSAIDs should not be used in treatment of stress fractures [letter]. Am Fam Physician. Oct 15 2004;70(8):1452, 1454. [Medline]. [Full Text].
12. Beck TJ, Ruff CB, Mourtada FA, et al. Dual-energy X-ray absorptiometry derived structural geometry for stress fracture prediction in male U.S. Marine Corps recruits. J Bone Miner Res. May 1996;11(5):645-53. [Medline].
13. Blomfeldt R, Törnkvist H, Eriksson K, et al. A randomised controlled trial comparing bipolar hemiarthroplasty with total hip replacement for displaced intracapsular fractures of the femoral neck in elderly patients. J Bone Joint Surg Br. Feb 2007;89(2):160-5. [Medline].
14. Kunesová M, Koudela K Jr, Koudela K Sr, Koudelová J. [Magnetic resonance imaging for examination of proximal femoral fractures: its contribution to clinical medicine] [Czech]. Acta Chir Orthop Traumatol Cech. Dec 2006;73(6):380-6. [Medline].
15. Lloyd T, Petit MA, Lin HM, Beck TJ. Lifestyle factors and the development of bone mass and bone strength in young women. J Pediatr. Jun 2004;144(6):776-82. [Medline].
16. Macaulay W, Yoon RS, Parsley B, Nellans KW, Teeny SM. Displaced femoral neck fractures: is there a standard of care?. Orthopedics. Sep 2007;30(9):748-9. [Medline].
17. Maitra RS, Johnson DL. Stress fractures. Clinical history and physical examination. Clin Sports Med. Apr 1997;16(2):259-74. [Medline].
18. Pihlajamäki HK, Ruohola JP, Weckström M, Kiuru MJ, Visuri TI. Long-term outcome of undisplaced fatigue fractures of the femoral neck in young male adults. J Bone Joint Surg Br. Dec 2006;88(12):1574-9. [Medline].
19. Provencher MT, Baldwin AJ, Gorman JD, Gould MT, Shin AY. Atypical tensile-sided femoral neck stress fractures: the value of magnetic resonance imaging. Am J Sports Med. Sep 2004;32(6):1528-34. [Medline].
20. Raaymakers EL. Fractures of the femoral neck: a review and personal statement. Acta Chir Orthop Traumatol Cech. 2006;73(1):45-59. [Medline].
21. Shimizu T, Miyamoto K, Masuda K, et al. The clinical significance of impaction at the femoral neck fracture site in the elderly. Arch Orthop Trauma Surg. Sep 2007;127(7):515-21. [Medline].
22. Strömqvist B, Hansson LI, Ljung P, Ohlin P, Roos H. Pre-operative and postoperative scintimetry after femoral neck fracture. J Bone Joint Surg Br. Jan 1984;66(1):49-54. [Medline]. [Full Text].
23. Yih-Shiunn L, Chien-Rae H, Wen-Yun L. Surgical treatment of undisplaced femoral neck fractures in the elderly. Int Orthop. Oct 2007;31(5):677-82. [Medline].

Article Last Updated: Nov 7, 2007