A femoral neck stress fracture is defined as the most common stress fracture of the femur and is a type of injury that stems from fatigue and insufficiency of the skeletal structure to maintain its function and integrity [1] [2]. Hence, it is not surprising that athletes (particularly endurance runners and other sports that put a significant weight on the hip joint for a prolonged period of time) and especially military personnel are the primary groups in whom a femoral neck stress fracture is encountered [1] [3] [4]. Elderly individuals suffering from a degenerative bone disease (mainly osteoporosis) are the second important class of patients who are at increased risk [1] [5]. A strong predilection towards female gender exists when it comes to femoral neck stress fracture and stress fractures in general [1] [2] [3]. In fact, the "female athlete triad" - amenorrhea, eating disorders, and osteopenia greatly predisposes to a stress fracture [1] [4]. The most important sign is anterior groin pain [5] [6]. Pain is usually absent at rest and appears during physical activity (for example, during running), one of the key findings that point toward this clinical entity [5] [6]. Additional features include erythema, local swelling, reduced range of motion at the hip joint, and pain when rotating the hip [1] [5].

• Hunting

  Prather H, Hunt D. Issues unique to the female runner. Phys Med Rehabil Clin N Am 2005;16:691–709. PubMed Google Scholar 6. Clement DB, Ammann W, Taunton JE, Lloyd-Smith R, Jesperson D, McKay H, Goldring J, Matheson GO. [link.springer.com]

• Erythema

  Additional features include erythema, local swelling, reduced range of motion at the hip joint, and pain when rotating the hip. [symptoma.com]

• Hip Pain

  Because the condition may lead to disastrous complications, femoral neck stress fracture must also be kept in mind in the differential diagnosis of pediatric hip pain. [ncbi.nlm.nih.gov]

• Knee Pain

  Patients commonly present with hip, groin, gluteal, thigh, or knee pain, depending on the location of the injury [18,72,73]. In a study by Clement and colleagues [72], 71 patients who had 74 stress fractures of the femur were studied. [78stepshealth.us]

  Slipped capital femoral epiphysis should be suspected in the child with a history of hip, groin, thigh or knee pain who walks with a limp. [aafp.org]

  Eliminating the existence of these other conditions is both necessary and more effective in determining a diagnosis of patellar stress fracture. 16, 21, 52 Femur Femoral stress fractures typically present with hip, groin, gluteal, thigh, or knee pain, [dovepress.com]

  Epub 2014 Mar 12.〔 PUBMED 〕 Usefulness of knee arthroscopy for diagnosis of knee pain in pediatric patients: comparison with preoperative clinical diagnosis. Arch Orthop Trauma Surg. 2013 May; 133(5): 669-73. [kofu.hosp.go.jp]

• Thigh Weakness

  How to spot a groin strain The most common signs include: Pain in the inner thigh or groin Pain with stretching Swelling or bruising of the inner thigh Weakness bringing the thigh together Treatment may include: Ice Reduced activity Rest Physical therapy [childrensortho.com]

• Joint Swelling

  Exercise or activity-induced anterior groin pain is the hallmark of this type of injury and can be accompanied by a reduced range of motion at the hip joint, swelling, local erythema, or bone tenderness. [symptoma.com]

• Excitement

  I try to avoid pain killers because then the pain subsides for a bit, and I get all excited thinking that it's going away, but once the Ibuprofin wears off, the pain comes back. The Dr. says he's not worried about it and that I am healing fine. [steadyhealth.com]

• Forgetful

  As of this weekend just gone, I'm either 5 or 6 weeks back into running (forget which) and I'm at 30/30/90. No adverse symptoms. [forum.slowtwitch.com]

Although signs and symptoms of a femoral neck stress fracture are evident in most cases, studies have confirmed that a significant amount of time (several weeks to even months) passes from initial injury to the diagnosis [1] [2] [5] [6] [7]. This delay in recognition puts the patient at risk for the development of numerous complications, one of them being displacement of the hip [1] [5]. Hence, the physician must obtain a detailed history (during which the exact course of symptoms and injury occurrence must be covered) and perform a physical examination that will reveal the location of the injury (although this may not be enough in the case of minor injuries) [1] [6]. The hop test (hopping on the affected extremity) is established as a reliable non-specific exam for bony injury of the hip and about 70% of individuals with a femoral neck stress fracture report pain during this examination [1]. To make a definite diagnosis, imaging studies need to be employed. Plain radiography is a useful first-line study that can detect stress fractures [1] [5], but many patients have normal radiographs, which is why more advanced studies are necessary when clinical and X-ray findings are not in accordance. Computed tomography (CT) is not recommended for evaluation of skeletal injuries, but magnetic resonance imaging (MRI) and bone scintigraphy are regarded as the crucial methods to delineate the exact site of fracture and its severity [1] [5] [6].

1. Avrahami D, Pajaczkowski JA. Femoral neck stress fracture in a female athlete: a case report. J Chiropr Med. 2012;11(4):273-279.
2. Niva MH, Kiuru MJ, Haataja R, Pihlajamaki HK. Fatigue injuries of the femur. J Bone Joint Surg Br. 2005;87:1385–1390
3. Niva M.H., Mattila VM, Kiuru MJ, Pihlajamaki HK. Bone stress injuries are common in female military trainees: a preliminary study. Clin Orthop Relat Res. 2009;467:2962–2969.
4. Okamoto S, Arai Y, Hara K, Tsuzihara T, Kubo T. A displaced stress fracture of the femoral neck in an adolescent female distance runner with female athlete triad: a case report. Sports Med Arthrosc Rehabil Ther Technol. 2010;2:6.
5. Onibere OA, Sugathan HK. A case report of missed femoral neck stress fracture. SICOT-J. 2015;1:2.
6. O’Kane JW. Anterior hip pain. Am Fam Physician. 1999;60(6):1687–1696.
7. Clough TM. Femoral neck stress fracture: the importance of clinical suspicion and early review. Br J Sports Med. 2002;36(4):308–309.