STRESS FRACTURE OF THE NECK OF THE FEMUR

Multiple stress fractures of unilateral femur: A case report

BACKGROUND

Stress fractures of the femoral neck are not common in clinical practice, and simultaneous stress fractures of the femoral neck and proximal femur of the unilateral femur are even more rare. We introduce a case of this type of fracture that was treated in our department, analyze the causes, and review similar stress fractures reported in the literature to provide references for the diagnosis and treatment of such conditions.

CASE SUMMARY

A 62-year-old female, with a free medical history, was admitted to the hospital mainly due to pain in the right hip and worsening pain in the right thigh. The patient had no obvious history of trauma. X-ray and computed tomography showed fracture of the femoral neck and proximal femur. The patient had undergone surgery 1 year prior to address a fracture of the left proximal femur that had occurred in a traffic accident. Our first consideration was stress fracture of the femoral neck; however, simultaneous stress fractures of the femoral neck and proximal femur of the unilateral femur were seen. The femoral neck stress fracture was a tension fracture, with obvious displacement and varus deformity of the hip. Considering that the patient was an elderly female, we performed total hip arthroplasty. Follow-up X-rays showed that the stress fracture of the proximal femur had mostly healed after 3 mo.

CONCLUSION

Muscle fatigue and hip varus deformity provide an anatomical basis for the occurrence of femoral neck stress fractures.

Early diagnosis of femoral neck stress fractures may decrease incidence of bilateral progression and surgical interventions: A case report and literature review

INTRODUCTION

Early intervention in femoral neck stress fractures (FNSFs) can be self- limiting, but they have an insidious presentation. High index of suspicion for an occult fracture is necessary to avoid bilateral progression and/or operative interventions.

CASE PRESENTATION

A 83-year-old female, non-athlete, presents with multiple comorbidities and progressive bilateral FNSFs. Initially the patient presented with groin pain and radiographs demonstrated a non-displaced compression type fracture of the right femoral neck without any inciting events. Subsequently, during a post-operative visit of her right hip, a work-up for new onset contralateral groin pain revealed a non-displaced tension type fracture on the left femoral neck. Both FNSFs were treated with percutaneous cannulated screw fixation.

DISCUSSION

Vitamin D deficiency, poor nutrition, and osteoporosis have been associated with developing stress fractures. This presents an interesting question of whether these frequently referenced risk factors play an interrelated role. Treatment algorithms are controversial, but have been successful in preventing the progression of occult stress fractures. Yet, identification of FNSFs represents a major challenge in diagnosis for clinicians.

CONCLUSION

This case report documents an uncommon fracture pattern in the elderly population. With an aging population, it is pertinent to avoid missed opportunities for prompt diagnosis and implementation of noninvasive methods of treatment. Therefore, paying attention to the risk factors with a high index of suspicion would be ideal.

Femoral Neck Stress Fractures in Sport: A Current Concepts Review

Femoral neck stress fractures (FNSFs) account for 3% of all sport-related stress fractures. The commonest causative sports are marathon and long-distance running.

The main types of FNSF are compression-sided, tension-sided and displaced. The most common reported symptom is exercise-related groin pain. Radiographs form the first line of investigation, with MRI the second-line investigation.

The management of FNSFs is guided by the location and displacement of the fracture. Delay in diagnosis is common and increases the likelihood of fracture displacement. Sporting outcomes are considerably worse for displaced fractures. Education programmes and treatment protocols can reduce the rates of displaced FNSFs.

This article aims to provide a current concepts review on the topic of FNSFs in sport, assess the current evidence on the epidemiology and pathophysiology of these injuries, detail the current recommendations for their imaging and management, and review the recorded sporting outcomes for FNSFs in the existing literature.

From this study, we conclude that although FNSFs are a rare injury, they should be considered in all athletes presenting with exercise-related hip pain, because delay in diagnosis and subsequent fracture displacement can significantly impair future return to sport. However, when detected early, FNSFs show promising results in terms of return-to-sport rates and times.

Simultaneous Bilateral Femoral Neck Stress Fracture in a Young Stone Mason

Unilateral stress fractures of the femoral neck are very uncommon and bilateral involvement is even rarer. They commonly occur in athletes, military recruits, older persons, or individuals with underlying metabolic disorders and very seldom in normal individuals. We present a rare case of simultaneous bilateral fracture neck of femur in a 25-year-old man who came with complaints of pain in bilateral groin for 1 month. There was no history of trauma or history suggestive of excessive activity prior to the onset of pain, but there was history of lifting heavy weights daily. On evaluation with MRI scan bilateral fracture of the femur neck was diagnosed and patient was operated on bilaterally with internal fixation done using dynamic hip screw. Patient then regained his routine activity over a period of 6 months and on follow-up at 1 year no avascular necrosis changes were seen in the femur head. We presented this case because of its unusual presentation and the diagnostic challenge it poses.

The comprehensive description of stress fractures: a new classification system

BACKGROUND

Stress fractures represent a fatigue failure of bone, occurring with a spectrum of severity of structural injury, and healing potential varies by location. There is no comprehensive classification system for stress fractures incorporating both clinical and radiographic characteristics of the injury that is applicable to all bones. We introduce a system that is reproducible, generalizable, easy to use, and clinically relevant, with three descriptors: fracture grade, fracture location, and imaging modality.

METHODS

After a review of current classification systems, a five-tier system was proposed to determine fracture grade: Grade I indicated asymptomatic stress reaction on imaging, Grade II indicated pain with no fracture line, Grade III indicated non-displaced fracture, Grade IV indicated displaced fracture, and Grade V indicated nonunion. Example cases of each grade with clinical vignettes and images were prepared to test the interobserver and intraobserver reliability of the system by the test and retest evaluation among fifteen clinicians. A questionnaire and recall test assessed the ease of use, clinical applicability, and recall accuracy.

RESULTS

Test and retest analysis showed that the system had almost perfect agreement in intraobserver reliability with a kappa value of 0.81. The overall intraobserver reliability showed almost perfect agreement with a kappa value of 0.81. Almost perfect agreement with a kappa value of 0.83 was also produced when these responses were compared with our assessment. The overall interobserver reliability had substantial agreement with a kappa value of 0.78. The reliability of the group compared with that of the answer key was almost perfect with a kappa value of 0.83. The recall test showed an overall accuracy of 97.3%. Of the fifteen evaluators who completed questionnaires, fourteen (93.3%) said that the system would be easily remembered, would facilitate communication among colleagues, and would be useful in clinical practice.

CONCLUSIONS

The proposed stress fracture classification system is clinically relevant, easily applied, and generalizable, and has excellent interobserver and intraobserver reliability.

The classification systems of stress fractures: a systematic review

BACKGROUND

Stress fractures of the upper and lower extremity are troublesome overuse injuries in athletes and nonathletes alike. These injuries have a broad spectrum of severity and prognosis. We performed a systematic search of the literature, which revealed multiple classification systems; however, we did not uncover a general system that offered both validated radiographic and clinical parameters.

METHODS

A literature search was conducted using Ovid/Medline, Embase, and the Cochrane Library, with publication dates ranging from 1960 to December 2009. Inclusion criteria included all studies and review articles regarding stress or fatigue fractures and their classification.

RESULTS

Forty-three studies and/or articles were identified for this review. Of these articles, 27 classification systems were referenced. Sixteen of the systems were applicable to any injury location, and 1 applied to specific bones (femoral neck, tibia, tarsal navicular, pars interarticularis, and fifth metatarsal). Four classification systems were referenced more often than others. Of the classification systems, 11 were based on radiographs alone, while the other 16 used a variety of radiographic modalities, including radiographs, bone scans, computed tomography, ultrasound, and magnetic resonance imaging.

CONCLUSION

There are many different stress fracture classification systems in the literature. These systems employ various imaging modalities, but few include clinical parameters. Many are site specific. Of those that are widely applicable, no general classification system has been shown to be reproducible, easily accessible, safe, inexpensive, and clinically relevant. A gold standard classification system for describing stress fractures has yet to be determined.

Stress fractures of the femur in athletes

Femoral stress fractures represent an uncommon but important lower-extremity injury in athletes and soldiers. Careful assessment of the involved and contralateral lower extremity and the spine is required to make the diagnosis. Based on a review of the literature, specific treatment is based on individual patient assessment. In most cases, nonoperative management results in an excellent outcome. Certain fractures will require operative intervention to prevent displacement or to reduce a displaced fracture and return stability to the lower extremity. Complications in athletes with femoral stress fractures are rare. Most athletes can expect to return to their preinjury level of competition, if they are compliant with the treatment plan.

Femoral neck stress fractures and metabolic bone disease

OBJECTIVE

To determine whether metabolic bone disease plays a role in the cause of femoral neck stress fractures.

STUDY DESIGN

Twenty-three patients with femoral neck stress fractures were enrolled prospectively in the study. Examination included computed tomography bone densitometry, trace mineral analysis, and histomorphometric analysis of the iliac crest in thirteen patients who underwent surgical treatment of their stress fractures. A control group of fifteen patients undergoing iliac crest bone grafting for scaphoid nonunions underwent similar examinations.

SETTING

Tertiary military medical center.

RESULTS

Patients with femoral neck stress fractures had lower bone mineral density than did control patients (p = 0.010), but no trace mineral deficiencies or consistent histomorphometric differences were noted.

CONCLUSIONS

Bone mineral density is decreased in patients with femoral neck stress fractures. Despite observations of decreased bone mineral density in the stress fracture group, osteoporosis, as determined by histomorphometry, is not a consistent finding.

Femoral neck stress fracture presenting as gluteal pain in a marathon runner: case report

A case is described of a 50-year-old man with a femoral neck stress fracture presenting as gluteal pain. An operative pinning procedure of the femoral neck was performed for stabilization. Femoral neck stress fractures are often misdiagnosed early in their presentation. The signs and symptoms can mimic those of more commonly seen disorders. Appropriate physiatric history and physical examination, along with indicated studies, will help prevent misdiagnosis and potentially serious complications associated with musculoskeletal pathology.

Stress fractures of the femoral neck

Stress fractures of the femoral neck are uncommon injuries. In general these injuries are seen in two distinct populations: (1) young, healthy, active individuals such as recreational runners, endurance athletes, or military recruits; and (2) the elderly who have osteoporosis. Stress fractures can be classified as either fatigue or insufficiency fractures and result from untoward cyclic loading or impaired bone quality. The key to treatment is early diagnosis, which may require scintigraphy or magnetic resonance imaging. Nondisplaced compression type stress fractures can be treated nonoperatively with protected weight-bearing and frequent radiographic followup. Tension type stress fractures should be stabilized internally to prevent the adverse consequences of fracture displacement.

Fatigue Fractures of the Femoral Neck in Athletes

Fatigue fractures of the femoral neck are potentially disabling injuries if the diagnosis is missed or delayed and proper treatment is not provided. Previously considered primarily an injury of military personnel, femoral-neck fatigue fractures are becoming increasingly more common among nonmilitary athletes. The pathogenesis of this condition is multifactorial. Ultimately, fracture is thought to be caused by repetitive submaximal stresses that occur with a frequency that exceeds the adaptive ability of the bone. The clinical hallmark of a femoral-neck fatigue fracture in an impact-loading athlete is nonspecific, activity-related hip pain that is relieved by rest. Plain radiographs obtained initially are often negative. Radionuclide imaging is useful but not specific. Magnetic resonance imaging has demonstrated better specificity, sensitivity, and accuracy than are available with other modalities in the diagnosis of this injury. Treatment of compression-side injuries is generally conservative. Treatment of tension-side injuries remains controversial. The authors recommend aggressive treatment of tension-side injuries to prevent the potentially catastrophic sequelae of displacement, which include osteonecrosis, malunion, and coxarthrosis.

Displaced stress fracture of the femoral neck in an active amenorrhoeic adolescent

Female athletes in endurance sports are at risk of osteoporosis which predisposes them to femoral neck stress fractures. These require early diagnosis and treatment to avoid catastrophic consequences.

A clinical study of stress fractures in sports activities

One hundred thirty-one patients with 169 stress fractures were treated between January 1984 and January 1990. The highest incidence was in teenage girls (25.5%), and the predominant sites were tibia (31.5%) and femur (12.5%). The mean interval between the start of hard training and the onset of symptoms was 2.7 months and the mean amount of increased activities was 93.7%. Volleyball (24.3%) and running (17.3%) had the majority of incidents, and 95 (72.5%) patients were professional athletes. Radionuclide bone scans were needed in 61 (46.6%) patients and 16 (12.2%) showed multiple lesions. Asymptomatic stress fractures were found in 12 (9.2%) patients, and only five showed recurrence at the other sites. Eleven (6.5%) cases were treated operatively, and involved the tarsal navicular (2.9%) and femur (2.4%).

Femoral neck stress fractures

Fifty-four femoral neck stress fractures were studied prospectively to evaluate treatment methods. Fifty-four fractures in 49 patients were identified in a 4 year prospective study that included 1,049 stress fractures of all types. From our evaluation of treatment methods, a modification of existing classification systems was developed based on radiographic findings and treatment. Differences from earlier studies were noted in racial diversity, in nonprogression of tension-side fractures, and in return to function.

Nine-year functional nonunion of a femoral neck stress fracture: treatment with internal fixation and fibular graft. A case report

Open reduction and internal fixation utilizing a full thickness fibular graft was performed on a patient who presented with a 9-year-old functional nonunion of a femoral neck stress fracture. During this period, the patient had remained fully ambulatory, with intermittent episodes of hip pain. Our experience indicates that the treatment of old, nonunited stress fractures of the femoral neck with a fibular bone graft and internal fixation contributes to a successful result, lending support while stimulating osteogenesis as the nonunion heals. Use of rigid internal fixation will eliminate motion at the site of the fracture, enhancing incorporation of the bone graft and, thereby, speeding the patient's recovery.

A Survey of Overuse and Traumatic Hip and Pelvic Injuries in Athletes

In brief: Two hundred and twenty-two hip and pelvic injuries in 204 patients (114 men and 90 women) were retrospectively assessed at a general sports medicine clinic over a two-year period. The three most common bone injuries were sacroiliitis, pelvic and femoral neck stress fractures, and osteitis pubis. The three most common soft-tissue injuries were gluteus medius strain/tendinitis, trochanteric bursitis, and hamstring strain. Running, fitness classes, and racket sports were the most commonly involved activities. Overuse accounted for 82.4% of injuries and trauma 17.6%. Treatment consisted of modified activity, local muscle rehabilitation, physiotherapy, oral anti-inflammatory medication, infrequent corticosteroid injection, orthoses and/or heel lifts, change of footwear, and gradual reintroduction of the specific sport.

Stress fractures of the femur in runners

Early diagnosis, followed by conservative management, permitted five of six long-distance runners to return to running after they had suffered stress fractures of the femur. The sixth patient developed a displaced fracture of the femoral neck which was openly reduced and internally fixated at surgery: this athlete returned to marathoning one year later. In the series there were two fractures of the femoral neck and four of the proximal medical shaft of the femur. Although early diagnosis depends upon a complete history, physical examination and x-ray film results, bone scanning is a further aid when x-ray films still do not confirm the presumptive diagnosis.