Skip to content

Avascular Necrosis On X Ray

MRI findings of AVN include decreased signal intensity in the subchondral region on both T1- and T2-weighted images, suggesting edema (water signal) in early disease. This relatively nonspecific finding is often localized in the medial aspect of the femoral head. This abnormality is observed in 96% of cases.Assouline-Dayan Y, Chang C, Greenspan A, et al. Pathogenesis and natural history of osteonecrosis. Semin Arthritis Rheum. 2002 Oct. 32(2):94-124. [QxMD MEDLINE Link].

Houdek MT, Wyles CC, Collins MS, Howe BM, Terzic A, Behfar A, et al. Stem Cells Combined With Platelet-rich Plasma Effectively Treat Corticosteroid-induced Osteonecrosis of the Hip: A Prospective Study. Clin Orthop Relat Res. 2018 Feb. 476 (2):388-397. [QxMD MEDLINE Link].
Shah KN, Racine J, Jones LC, Aaron RK. Pathophysiology and Risk Factors for Osteonecrosis. Current Reviews in Musculoskeletal Medicine. Sept 2015. 8(3): 201–209:[QxMD MEDLINE Link]. [Full Text].Dudkiewicz I, Covo A, Salai M, et al. Total hip arthroplasty after avascular necrosis of the femoral head: does etiology affect the results?. Arch Orthop Trauma Surg. 2004 Mar. 124(2):82-5. [QxMD MEDLINE Link].

Iqbal B, Currie G. Value of SPECT/CT in the diagnosis of avascular necrosis of the head of femur: A meta-analysis. Radiography (Lond). 2022 May. 28 (2):560-564. [QxMD MEDLINE Link].Hernigou P, Dubory A, Homma Y, Guissou I, Flouzat Lachaniette CH, Chevallier N, et al. Cell therapy versus simultaneous contralateral decompression in symptomatic corticosteroid osteonecrosis: a thirty year follow-up prospective randomized study of one hundred and twenty five adult patients. Int Orthop. 2018 May 9. [QxMD MEDLINE Link].

Bachiller FG, Caballer AP, Portal LF. Avascular necrosis of the femoral head after femoral neck fracture. Clin Orthop Relat Res. 2002 Jun. 87-109. [QxMD MEDLINE Link].van den Blink QU, Garcez K, Henson CC, Davidson SE, Higham CE. Pharmacological interventions for the prevention of insufficiency fractures and avascular necrosis associated with pelvic radiotherapy in adults. Cochrane Database Syst Rev. 2018 Apr 23. 4:CD010604. [QxMD MEDLINE Link]. Hasse B, Ledergerber B, Egger M, Flepp M, Bachmann S, Bernasconi E, et al. Antiretroviral treatment and osteonecrosis in patients of the Swiss HIV Cohort Study: a nested case-control study. AIDS Res Hum Retroviruses. 2004 Sep. 20(9):909-15. [QxMD MEDLINE Link]. In early AVN, osteoblastic activity and blood flow are increased; thus, the sensitivity of radionuclide bone scan is better than that of plain films at this stage.In the early stage, interstitial edema and plasmostasis is confined to the bone marrow. As the severity progresses, osteocytes continue to disappear and necrotic tissue fills the medullary spaces. New living bone is laminated onto dead trabeculae with partial resorption of dead bone. In the subchondral trabeculae, bone resorption exceeds formation leading to the net removal of bone, loss of structural integrity of trabeculae, subchondral fracture, and joint incongruity.

Van Laere C, Mulier M, Simon JP, et al. Core decompression for avascular necrosis of the femoral head. Acta Orthop Belg. 1998 Sep. 64(3):269-72. [QxMD MEDLINE Link].
MRI is the most sensitive and specific imaging procedure for AVN, of the hip with an overall sensitivity that exceeds 90%. The specificity of MRI is also very high. The use of gadolinium is particularly useful in early detection.A meta-analysis of seven studies of SPECT in patients with avascular necrosis (AVN) of the femoral head reported a pooled sensitivity and specificity of 94% (95% confidence interval of 87-97%) and 75% (95% confidence interval of 68-81%) respectively. Lovecchio FC, Manalo JP, Demzik A, Sahota S, Beal M, Manning D. Avascular Necrosis Is Associated With Increased Transfusions and Readmission Following Primary Total Hip Arthroplasty. Orthopedics. 2017 May 1. 40 (3):171-176. [QxMD MEDLINE Link]. Luo RB, Lin T, Zhong HM, Yan SG, Wang JA. Evidence for using alendronate to treat adult avascular necrosis of the femoral head: a systematic review. Med Sci Monit. 2014 Nov 26. 20:2439-47. [QxMD MEDLINE Link].

Ng FH, Lai TKB, Lam SY, Pan NY, Luk WH. Hybrid Magnetic Resonance Imaging with Single Photon Emission Computed Tomography/Computed Tomography Bone Scan for Diagnosis Of Avascular Necrosis of Femoral Head. J Clin Imaging Sci. 2021. 11:2. [QxMD MEDLINE Link]. [Full Text].
Bose VC, Baruah BD. Resurfacing arthroplasty of the hip for avascular necrosis of the femoral head: a minimum follow-up of four years. J Bone Joint Surg Br. 2010 Jul. 92(7):922-8. [QxMD MEDLINE Link].

Lau RL, Perruccio AV, Evans HM, Mahomed SR, Mahomed NN, Gandhi R. Stem cell therapy for the treatment of early stage avascular necrosis of the femoral head: a systematic review. BMC Musculoskelet Disord. 2014 May 16. 15:156. [QxMD MEDLINE Link]. [Full Text].
Aaron RK, Voisinet A, Racine J, Ali Y, Feller ER. Corticosteroid-associated avascular necrosis: dose relationships and early diagnosis. Ann N Y Acad Sci. 2011 Dec. 1240(1):38-46. [QxMD MEDLINE Link].

William Gilliland, MD, MPHE, FACP, FACR Staff Rheumatologist, Walter Reed Army Medical Center; Professor of Medicine, Assistant Dean of Curriculum, Uniformed Services University of the Health Sciences
Qi WX, Tang LN, He AN, Yao Y, Shen Z. Risk of osteonecrosis of the jaw in cancer patients receiving denosumab: a meta-analysis of seven randomized controlled trials. Int J Clin Oncol. 2014 Apr. 19(2):403-10. [QxMD MEDLINE Link].[Guideline] Murphey MD, Roberts CC, Bencardino JT, Appel M, Arnold E, Chang EY, et al. ACR Appropriateness Criteria Osteonecrosis of the Hip. J Am Coll Radiol. 2016 Feb. 13 (2):147-55. [QxMD MEDLINE Link].

Woo SB, Hellstein JW, Kalmar JR. Narrative [corrected] review: bisphosphonates and osteonecrosis of the jaws. Ann Intern Med. 2006 May 16. 144(10):753-61. [QxMD MEDLINE Link].
Histology is the criterion standard for diagnosis of AVN. However, bone biopsy is not routinely performed because of the availability of sensitive noninvasive tests such as MRI.Hasegawa Y, Iwata H, Torii S, et al. Vascularized pedicle bone-grafting for nontraumatic avascular necrosis of the femoral head. A 5- to 11-year follow-up. Arch Orthop Trauma Surg. 1997. 116(5):251-8. [QxMD MEDLINE Link].

Wang GJ, Sweet DE, Reger SI, et al. Fat-cell changes as a mechanism of avascular necrosis of the femoral head in cortisone-treated rabbits. J Bone Joint Surg Am. 1977 Sep. 59(6):729-35. [QxMD MEDLINE Link]. Zuo W, Sun W, Zhao D, Gao F, Su Y, Li Z. Investigating Clinical Failure of Bone Grafting through a Window at the Femoral Head Neck Junction Surgery for the Treatment of Osteonecrosis of the Femoral Head. PLoS One. 2016. 11 (6):e0156903. [QxMD MEDLINE Link]. [Full Text]. Plain radiographic findings are unremarkable in early stages of AVN. Nevertheless, the American College of Radiology considers x-ray of the pelvis the most appropriate initial imaging study in patients at risk for AVN who present with hip pain.Both an anteroposterior view of the pelvis and a frog-leg lateral view of the hip are necessary, as articular collapse or cortical depression may be seen on only one of those projections.Fink JC, Leisenring WM, Sullivan KM, et al. Avascular necrosis following bone marrow transplantation: a case-control study. Bone. 1998 Jan. 22(1):67-71. [QxMD MEDLINE Link].Goker B, Block JA. Risk of contralateral avascular necrosis (AVN) after total hip arthroplasty (THA) for non-traumatic AVN. Rheumatol Int. 2006 Jan. 26(3):215-9. [QxMD MEDLINE Link].Khan AA, Sándor GK, Dore E, Morrison AD, Alsahli M, Amin F, et al. Bisphosphonate associated osteonecrosis of the jaw. J Rheumatol. 2009 Mar. 36(3):478-90. [QxMD MEDLINE Link].

The central area of decreased uptake is surrounded by an area of increased uptake. This phenomenon is known as the doughnut sign and indicates the reactive zone surrounding the necrotic area.
Histology is the criterion standard for diagnosis of AVN, although it is usually unnecessary. The histologic specimen is usually obtained during surgery, although it is occasionally obtained during diagnostic bone biopsy. Histologic changes are observed in both cortical bone and bone marrow.Piuzzi NS, Chahla J, Schrock JB, LaPrade RF, Pascual-Garrido C, Mont MA, et al. Evidence for the Use of Cell-Based Therapy for the Treatment of Osteonecrosis of the Femoral Head: A Systematic Review of the Literature. J Arthroplasty. 2017 May. 32 (5):1698-1708. [QxMD MEDLINE Link].

Chiu HY, Wang IT, Huang WF, Tsai YW, Shiu MN, Tsai TF. Increased risk of avascular necrosis in patients with psoriatic disease: A nationwide population-based matched cohort study. J Am Acad Dermatol. 2017 May. 76 (5):903-910.e1. [QxMD MEDLINE Link].
Ristow JJ, Ellison CM, Mickschl DJ, Berg KC, Haidet KC, Gray JR, et al. Outcomes of shoulder replacement in humeral head avascular necrosis. J Shoulder Elbow Surg. 2018 Sep 14. [QxMD MEDLINE Link].

Several different staging systems have been developed and continue to be used. Ficat initially developed an AVN staging system based on radiologic findings. This staging system was revised after the widespread use of MRI in the workup of AVN. The staging system presented in the below table is based on the consensus of the Subcommittee of Nomenclature of the International Association on Bone Circulation and Bone Necrosis (ARCO: Association of Research Circulation Osseous).The most important consideration is collapse of the femoral head cortex. Repair and complete recovery may be possible prior to collapse. Afterward, the collapse is irreversible. Pilge H, Bittersohl B, Schneppendahl J, Hesper T, Zilkens C, Ruppert M, et al. Bone Marrow Aspirate Concentrate in Combination With Intravenous Iloprost Increases Bone Healing in Patients With Avascular Necrosis of the Femoral Head: A Matched Pair Analysis. Orthop Rev (Pavia). 2016 Nov 17. 8 (4):6902. [QxMD MEDLINE Link]. [Full Text]. Hernigou P, Trousselier M, Roubineau F, Bouthors C, Chevallier N, Rouard H, et al. Stem Cell Therapy for the Treatment of Hip Osteonecrosis: A 30-Year Review of Progress. Clin Orthop Surg. 2016 Mar. 8 (1):1-8. [QxMD MEDLINE Link]. [Full Text].Mathieu D, Marroni A, Kot J. Tenth European Consensus Conference on Hyperbaric Medicine: recommendations for accepted and non-accepted clinical indications and practice of hyperbaric oxygen treatment. Diving Hyperb Med. 2017 Mar. 47 (1):24-32. [QxMD MEDLINE Link]. [Full Text].

Can you see avascular necrosis on X-ray?
X-rays. They can reveal bone changes that occur in the later stages of avascular necrosis. In the condition’s early stages, X-rays usually don’t show any problems. MRI and CT scan.
Advanced AVN is characterized by deformity of the articular surface and by calcification, which are also easily detected with radiography and CT scanning.Wang CJ, Cheng JH, Huang CC, Yip HK, Russo S. Extracorporeal shockwave therapy for avascular necrosis of femoral head. Int J Surg. 2015 Dec. 24 (Pt B):184-7. [QxMD MEDLINE Link].

Aldridge JM 3rd, Urbaniak JR. Avascular necrosis of the femoral head: role of vascularized bone grafts. Orthop Clin North Am. 2007 Jan. 38(1):13-22, v. [QxMD MEDLINE Link].
Ninomiya S. An epidemiological survey of idiopathic avascular necrosis of the femoral head in Japan. Annual Report of Japanese Investigation Committee for Intractable Disease. 1989.Computed tomography (CT) is not commonly used for assessment of osteonecrosis in pediatric patients. In adults, CT is used principally to provide information for surgical planning, by determining the severity and location of articular collapse and providing evidence of early secondary degenerative joint disease.

Felten R, Perrin P, Caillard S, Moulin B, Javier RM. Avascular osteonecrosis in kidney transplant recipients: Risk factors in a recent cohort study and evaluation of the role of secondary hyperparathyroidism. PLoS One. 2019. 14 (2):e0212931. [QxMD MEDLINE Link]. [Full Text].
The next stage is characterized by a reparative process (reactive zone) and shows low signal intensity on T1-weighted scans and high signal intensity on T2-weighted scans. This finding is diagnostic for AVN (see images below).Bagan JV, Murillo J, Jimenez Y, et al. Avascular jaw osteonecrosis in association with cancer chemotherapy: series of 10 cases. J Oral Pathol Med. 2005 Feb. 34(2):120-3. [QxMD MEDLINE Link].

What are red flags for avascular necrosis?
The pain from acute, evolving AVN is unremitting; rest pain is a red flag for this diagnosis. With degeneration, the pattern of pain resembles any arthrosis. Swelling is a key feature; it can resemble Charcot in the acute phase.
Rolston VS, Patel AV, Learch TJ, Li D, Karayev D, Williams C, et al. Prevalence and Associations of Avascular Necrosis of the Hip in a Large Well-characterized Cohort of Patients With Inflammatory Bowel Disease. J Clin Rheumatol. 2018 May 24. [QxMD MEDLINE Link].

Steffen RT, Athanasou NA, Gill HS, Murray DW. Avascular necrosis associated with fracture of the femoral neck after hip resurfacing: histological assessment of femoral bone from retrieval specimens. J Bone Joint Surg Br. 2010 Jun. 92(6):787-93. [QxMD MEDLINE Link].
Freiberger JJ. Utility of hyperbaric oxygen in treatment of bisphosphonate-related osteonecrosis of the jaws. J Oral Maxillofac Surg. 2009 May. 67(5 Suppl):96-106. [QxMD MEDLINE Link].

How do you diagnose avascular necrosis?
How is avascular necrosis diagnosed?X-ray. This test uses invisible electromagnetic energy beams to make images of internal tissues, bones, and organs onto film.Computed tomography scan (also called a CT or CAT scan). … Magnetic resonance imaging (MRI). … Radionuclide bone scan. … Biopsy. … Functional evaluation of bone.
In mild-to-moderate AVN, radiographs demonstrate sclerosis and changes in bone density. In advanced disease, bone deformities, such as flattening, subchondral radiolucent lines (crescent sign), and collapse of the femoral head, are evident (see images below).Urbaniak JR, Coogan PG, Gunneson EB, et al. Treatment of osteonecrosis of the femoral head with free vascularized fibular grafting. A long-term follow-up study of one hundred and three hips. J Bone Joint Surg Am. 1995 May. 77(5):681-94. [QxMD MEDLINE Link]. Han J, Gao F, Li Y, Ma J, Sun W, Shi L, et al. The Use of Platelet-Rich Plasma for the Treatment of Osteonecrosis of the Femoral Head: A Systematic Review. Biomed Res Int. 2020. 2020:2642439. [QxMD MEDLINE Link]. [Full Text]. Kawai K, Tamaki A, Hirohata K. Steroid-induced accumulation of lipid in the osteocytes of the rabbit femoral head. A histochemical and electron microscopic study. J Bone Joint Surg Am. 1985 Jun. 67(5):755-63. [QxMD MEDLINE Link].

What are the black lines on Xrays?
The bones in the x-ray identify themselves as the while areas, and the air is black. So, you can understand the breaches of the bones will appear as the sharp black lines. In case of the hairline fractures, the fractures will appear as a thin black line.
Dodson TB. Intravenous bisphosphonate therapy and bisphosphonate-related osteonecrosis of the jaws. J Oral Maxillofac Surg. 2009 May. 67(5 Suppl):44-52. [QxMD MEDLINE Link].Lawson-Ayayi S, Bonnet F, Bernardin E, et al. Avascular necrosis in HIV-infected patients: a case-control study from the Aquitaine Cohort, 1997-2002, France. Clin Infect Dis. 2005 Apr 15. 40(8):1188-93. [QxMD MEDLINE Link]. Enright H, Haake R, Weisdorf D. Avascular necrosis of bone: a common serious complication of allogeneic bone marrow transplantation. Am J Med. 1990 Dec. 89(6):733-8. [QxMD MEDLINE Link]. Gao F, Sun W, Li Z, Guo W, Wang W, Cheng L, et al. High-Energy Extracorporeal Shock Wave for Early Stage Osteonecrosis of the Femoral Head: A Single-Center Case Series. Evid Based Complement Alternat Med. 2015. 2015:468090. [QxMD MEDLINE Link].Claßen T, Becker A, Landgraeber S, Haversath M, Li X, Zilkens C, et al. Long-term Clinical Results after Iloprost Treatment for Bone Marrow Edema and Avascular Necrosis. Orthop Rev (Pavia). 2016 Mar 21. 8 (1):6150. [QxMD MEDLINE Link]. [Full Text].Sugano N, Takaoka K, Ohzono K, et al. Rotational osteotomy for non-traumatic avascular necrosis of the femoral head. J Bone Joint Surg Br. 1992 Sep. 74(5):734-9. [QxMD MEDLINE Link].SPECT scanning provides images of the radioactivity within the target organ in 3 dimensions. With this modality, overlying and underlying areas of radioactivity may be separated into sequential tomographic planes, thus providing increased image contrast and improved lesion detection and localization, as compared with planar scintigraphy. SPECT scanning is used as an alternative to MRI when MRI cannot be performed or when the results of MRI are indeterminate.

The ACR advises that MRI is the most sensitive and specific imaging modality for diagnosis and provides optimal evaluation of the likelihood of articular collapse. The ACR found insufficient medical literature to conclude if patients would benefit from CT without IV contrast but it may be appropriate.
Bosco G, Vezzani G, Mrakic Sposta S, Rizzato A, Enten G, Abou-Samra A, et al. Hyperbaric oxygen therapy ameliorates osteonecrosis in patients by modulating inflammation and oxidative stress. J Enzyme Inhib Med Chem. 2018 Dec. 33 (1):1501-1505. [QxMD MEDLINE Link]. [Full Text].

Pritchett JW. Statin therapy decreases the risk of osteonecrosis in patients receiving steroids. Clin Orthop. 2001 May. (386):173-8. [QxMD MEDLINE Link].
During a physical exam, a health care provider will press around your joints, checking for tenderness. They might also move the joints through different positions to see if the range of motion is lessened. Because most people don’t develop symptoms until avascular necrosis is advanced, your health care provider might recommend surgery. The options include: Avascular necrosis (AVN) within bone is a rare pathology but can affect many sites in the foot and ankle. AVN of the first metatarsal head will not be covered in this document but it is a rare, but frequently quoted, complication of correction of hallux valgus using a lateral release and a distal chevron osteotomy.

Pain and swelling isolated to the base of the toe. Pain may be metatarsalgic in nature or nocturnal (typical of AVN). The affected toe may be elevated form the ground, swollen and, in later stages, dislocated dorsally.

Figure 10: Example of circumferential plating of a comminuted navicular fracture without lag screws; robust attention to preserving the medial column; late collapse of the navicular can be seen
Figure 4: sagittal CT slice through the 2nd MTPJ showing the relative involvement of the dorsum of the head; this illustrates how a dorsal wedge resection osteotomy would rotate articular surface into contact with the base of the proximal phalanx

Petrie MJ, Blakey CM, Chadwick C, Davies HG, Blundell, CM, Davies MB. A new and reliable classification for fractures of the navicular and associated injuries to the midfoot. Bone Joint J 2018:100-B (2);176-182.
In a seminal paper from 1970, Mulfinger & Trueta described the blood supply to the talus: anastomoses principally located inferiorly within the sinus tarsi/tarsal canal and from within the deltoid ligament (Figures 12&13). Sources of these anastomoses are:

Surgical appearances are classic of a punched out dorso-central lesion often with loose bodies and de-laminated cartilage (Figure 2). Histologically, most reports suggest a clear picture of AVN.
Although the eponymous condition known as Freiberg’s disease has historically been viewed as a separate disease process, it shares all pathological features and some clinical and radiological features with AVN affecting other bones in the hindfoot.Smillie (1957) described 5 progressive stages of the disease based upon a mixture of radiographic and intra-operative findings. This staging process does not act as a tool for determining treatment.

What does bone necrosis look like on X-ray?
The classic MR appearance of osteonecrosis is that of a segmental area of low signal intensity in the subchondral bone, bounded by a low signal intensity border. This border may sometimes appear as a dark line adjacent to a bright line — the so-called “double line sign”.
Impaired vascularity: approx 1/3 of the population may have an absent 2 dorsal metatarsal artery ≈ possible poor watershed blood supply from neighbouring vessels

The pain from acute, evolving AVN is unremitting; rest pain is a red flag for this diagnosis. With degeneration, the pattern of pain resembles any arthrosis. Swelling is a key feature; it can resemble Charcot in the acute phase.
Figure 7b: the well-corticated appearance of a chronic stress fracture in the axial plane watershed between the medial 2/3 and lateral 1/3 of the navicularDeformity occurs with collapse of the talus and is thus governed by the location of the collapse. Not infrequently, the tibial plafond and calcaneus can demonstrate simultaneous areas of AVN. Joint replacement. This surgical procedure removes and replaces an arthritic or damaged joint with an artificial joint. This may be considered only after other treatment options have failed to relieve from pain and/or disability. Computed tomography scan (also called a CT or CAT scan). This is an imaging test that uses X-rays and a computer to make detailed images of the body. A CT scan shows details of the bones, muscles, fat, and organs. CT scans are more detailed than general X-rays.Biopsy. A procedure in which tissue samples are removed (with a needle or during surgery) from the body for exam under a microscope. It’s done to find cancer or other abnormal cells or remove tissue from the affected bone.

This condition may happen in any bone. It most commonly happens in the ends of a long bone. It may affect one bone, several bones at one time, or different bones at different times.
Core decompression. For this surgical procedure, the inner layer of bone is removed to reduce pressure, increase blood flow, and slow or stop bone and/or joint destruction.Radionuclide bone scan. This nuclear imaging technique uses a very small amount of radioactive material, which is injected into the blood to be detected by a scanner. This test shows blood flow to the bone and cell activity within the bone.

The goal of treatment is to improve functionality and stop further damage to the bone or joint. Treatments are needed to keep joints from breaking down, and may include:
Magnetic resonance imaging (MRI). This test uses large magnets, radiofrequencies, and a computer to make detailed images of organs and structures within the body.Avascular necrosis is a disease that results from the temporary or permanent loss of blood supply to the bone. It happens most commonly in the ends of a long bone.

Avascular necrosis is a disease that results from the temporary or permanent loss of blood supply to the bone. When blood supply is cut off, the bone tissue dies and the bone collapses. If avascular necrosis happens near a joint, the joint surface may collapse.
Bisphosphonates are associated with osteonecrosis of the mandible. Prolonged, repeated exposure to high pressures (as experienced by commercial and military divers) has been linked to AVN, though the relationship is not well understood.Other techniques such as metal on metal resurfacing may not be suitable in all cases of avascular necrosis; its suitability depends on how much damage has occurred to the femoral head. Bisphosphonates which reduce the rate of bone breakdown may prevent collapse (specifically of the hip) due to AVN.

Is AVN Stage 1 curable?
Although physical therapy cannot cure avascular necrosis, it can slow down the progression of the disease and decrease associated pain. It is suggested that patients with Stage 1 and 2 osteonecrosis could benefit from a physical therapy program.
Risk factors include bone fractures, joint dislocations, alcoholism, and the use of high-dose steroids. The condition may also occur without any clear reason. The most commonly affected bone is the femur. Other relatively common sites include the upper arm bone, knee, shoulder, and ankle. Diagnosis is typically by medical imaging such as X-ray, CT scan, or MRI. Rarely biopsy may be used.Progression of the disease could possibly be halted by transplanting nucleated cells from bone marrow into avascular necrosis lesions after core decompression, although much further research is needed to establish this technique. In many cases, there is pain and discomfort in a joint which increases over time. While it can affect any bone, about half of cases show multiple sites of damage. The intravertebral vacuum cleft sign (at white arrow) is a sign of avascular necrosis. Avascular necrosis of a vertebral body after a vertebral compression fracture is called Kümmel’s disease.

What are the stages of X-ray avascular necrosis?
Stage 1 has a normal x-rays but MRI reveals the dead bone. Stage 2 can be seen on regular x-ray but there is no collapse of the femoral ball. Stage 3 shows signs of collapse (called a crescent sign) on x-ray. Stage 4 has collapse on x-ray and signs of cartilage damage (osteoarthritis).
When AVN affects the scaphoid bone, it is known as Preiser disease. Another named form of AVN is Köhler disease, which affects the navicular bone of the foot, primarily in children. Yet another form of AVN is Kienböck’s disease, which affects the lunate bone in the wrist.The amount of disability that results from avascular necrosis depends on what part of the bone is affected, how large an area is involved, and how effectively the bone rebuilds itself. The process of bone rebuilding takes place after an injury as well as during normal growth. Normally, bone continuously breaks down and rebuilds—old bone is resorbed and replaced with new bone. The process keeps the skeleton strong and helps it to maintain a balance of minerals. In the course of avascular necrosis, however, the healing process is usually ineffective and the bone tissues break down faster than the body can repair them. If left untreated, the disease progresses, the bone collapses, and the joint surface breaks down, leading to pain and arthritis.

X-ray images of avascular necrosis in the early stages usually appear normal. In later stages it appears relatively more radio-opaque due to the nearby living bone becoming resorbed secondary to reactive hyperemia. The necrotic bone itself does not show increased radiographic opacity, as dead bone cannot undergo bone resorption which is carried out by living osteoclasts. Late radiographic signs also include a radiolucency area following the collapse of subchondral bone (crescent sign) and ringed regions of radiodensity resulting from saponification and calcification of marrow fat following medullary infarcts.
The main risk factors are bone fractures, joint dislocations, alcoholism, and the use of high-dose steroids. Other risk factors include radiation therapy, chemotherapy, and organ transplantation. Osteonecrosis is also associated with cancer, lupus, sickle cell disease, HIV infection, Gaucher’s disease, and Caisson disease (dysbaric osteonecrosis). The condition may also occur without any clear reason.Cases of avascular necrosis have been identified in a few high-profile athletes. It abruptly ended the career of American football running-back Bo Jackson in 1991. Doctors discovered Jackson to have lost all of the cartilage supporting his hip while he was undergoing tests following a hip-injury he had on the field during a 1991 NFL Playoff game. Avascular necrosis of the hip was also identified in a routine medical check-up on quarterback Brett Favre following his trade to the Green Bay Packers in 1992. However, Favre would go on to have a long career at the Packers.

How quickly does avascular necrosis develop?
AVN can progress through these stages quite rapidly over a period of just a few months or it may take 12 – 18 months. This is in contrast to osteoarthritis of the hip which is a generally slowly progressive condition that takes years to develop.
A variety of methods may be used to treat the most common being the total hip replacement (THR). However, THRs have a number of downsides including long recovery times and short life spans of the hip joints. THRs are an effective means of treatment in the older population; however, in younger people, they may wear out before the end of a person’s life.Upon reperfusion, repair of bone occurs in 2 phases. First, there is angiogenesis and movement of undifferentiated mesenchymal cells from adjacent living bone tissue grow into the dead marrow spaces, as well as entry of macrophages that degrade dead cellular and fat debris. Second, there is cellular differentiation of mesenchymal cells into osteoblasts or fibroblasts. Under favorable conditions, the remaining inorganic mineral volume forms a framework for establishment of new, fully functional bone tissue.

Other treatments include core decompression, where internal bone pressure is relieved by drilling a hole into the bone, and a living bone chip and an electrical device to stimulate new vascular growth are implanted; and the free vascular fibular graft (FVFG), in which a portion of the fibula, along with its blood supply, is removed and transplanted into the femoral head. A 2016 Cochrane review found no clear improvement between people who have had hip core decompression and participate in physical therapy, versus physical therapy alone. There is additionally no strong research on the effectiveness of hip core decompression for people with sickle cell disease.Pathology of avascular necrosis, with a photograph of a cross-section of the involved bone at top left. The reactive zone shows irregular trebaculae with empty lacunae, and fibrosis of the marrow space.The hematopoietic cells are most sensitive to low oxygen and are the first to die after reduction or removal of the blood supply, usually within 12 hours. Experimental evidence suggests that bone cells (osteocytes, osteoclasts, osteoblasts etc.) die within 12–48 hours, and that bone marrow fat cells die within 5 days.In children, avascular osteonecrosis can have several causes. It can occur in the hip as part of Legg–Calvé–Perthes syndrome, and it can also occur as a result after malignancy treatment such as acute lymphoblastic leukemia and allotransplantation.

When do you suspect avascular necrosis?
Symptoms. AVN can cause pain in the hip, thigh or knee. The hip joint usually becomes stiffer, and pain can either start abruptly or build over weeks or months.
Avascular necrosis most commonly affects the ends of long bones such as the femur. Other common sites include the humerus, knees, shoulders, ankles and the jaw.

Another high-profile athlete was American road racing cyclist Floyd Landis, winner of the 2006 Tour de France, the title being subsequently stripped from his record by cycling’s governing bodies after his blood samples tested positive for banned substances. During that tour, Landis was allowed cortisone shots to help manage his ailment, despite cortisone also being a banned substance in professional cycling at the time.

Treatments may include medication, not walking on the affected leg, stretching, and surgery. Most of the time surgery is eventually required and may include core decompression, osteotomy, bone grafts, or joint replacement. About 15,000 cases occur per year in the United States. People 30 to 50 years old are most commonly affected. Males are more commonly affected than females.

Avascular necrosis (AVN), also called osteonecrosis or bone infarction, is death of bone tissue due to interruption of the blood supply. Early on, there may be no symptoms. Gradually joint pain may develop which may limit the ability to move. Complications may include collapse of the bone or nearby joint surface.

Avascular necrosis usually affects people between 30 and 50 years of age; about 10,000 to 20,000 people develop avascular necrosis of the head of the femur in the US each year.Osteonecrosis is most common in the hip, but also seen in the humerus, knee, and talus and more rarely seen in the smaller bones of the wrist such as the lunate or scaphoid.

Avascular necrosis/Osteonecrosis is a degenerative bone condition characterised by the death of cellular components of the bone secondary to an interruption of the subchondral blood supply. It typically affects the epiphysis of long bones at weight-bearing joints. Advanced disease may result in subchondral collapse which threatens the viability of the joint involved. Non-traumatic cases will typically present with mechanical pain of variable onset and severity and often difficult to localize. In early disease, the physical examination is often normal which inevitably causes a delay in diagnosis.The content on or accessible through Physiopedia is for informational purposes only. Physiopedia is not a substitute for professional advice or expert medical services from a qualified healthcare provider. Read moreNonoperative treatment begins with patient education and addressing known risk factors, such as smoking and alcohol abuse. In addition, corticosteroids should be avoided. A functional outcome measure is useful for establishing the patient’s baseline function and setting measurable goals. See Outcome Measures Database for more. Appropriate treatment for avascular necrosis is necessary to prevent further deterioration of the joint. If untreated, most patients will experience severe pain and limitation of movement within two years. Although physical therapy cannot cure avascular necrosis, it can slow down the progression of the disease and decrease associated pain. It is suggested that patients with Stage 1 and 2 osteonecrosis could benefit from a physical therapy program. Most patients will eventually need surgical treatment, such as core decompression or arthroplasty.

Physical therapy treatment focuses on exercises to maintain joint mobility and strengthen the muscles around the affected joint. During physical therapy, excessive compressive and shear forces on the joint should be avoided. The outcome depends on the lesion’s size and stage at the initiation of the treatment.
For example, if a case presents itself where the patient has osteonecrosis of the femoral head. Avascular necrosis most commonly affects the hip in more than 72% of the cases. The patient will have mild chronic pain in the hip, the groin, around the buttocks and at the antero-medial thigh, with a normal radiograph, they should undergo observation for ONFH and a Hip joints MRI. This pain is most commonly aggravated by activity and internal rotation in flexion. As the disease progresses, the pain may also become present at rest. Without treatment, 85% will progress to the collapse of the articular surface and will eventually require total hip arthroplasty.Physical therapy after surgery is also a key component for recovery. It starts immediately the day after surgery. They prepare the patients for discharge by showing them how to do their everyday activities like getting in and out of bed and walking with a walker or crutches. (level 5)

What is the gold standard test for avascular necrosis?
MRI and CT scans can provide a detailed image of the changes in bone occurring at an early stage of the disease. However, MRI is considered the gold standard for the detection of AVN.
When refering to evidence in academic writing, you should always try to reference the primary (original) source. That is usually the journal article where the information was first stated. In most cases Physiopedia articles are a secondary source and so should not be used as references. Physiopedia articles are best used to find the original sources of information (see the references list at the bottom of the article).

In the beginning, this disease is asymptomatic. It is also plausible there is a segmental collapse present and the patient doesn’t feel it. As the disease progresses, the hip can become stiffer, which is visible in the gait of the patient when he starts to limp. Pain is also observed by support on the leg, in the buttock, groin, and thigh.
Osteonecrosis can be diagnosed with a thorough check of the historical background of the patient combined with physical examination. Steroid exposure and alcohol abuse are important risk factors. The age of the patient can also provide clues to the disease because patients with osteonecrosis are generally younger than those with osteoarthritis. Locking, popping, or a painful click during mobilization of the affected joint can point to the presence of loose osteochondral fragments. In further stages of the disease, loss of mobilization and increased pain can be detected. Once osteonecrosis is detected, the physician should assess other joints that may be at risk, such as the hip, shoulder, and knee. Symptoms include pain and decreased range of motion in the affected joint. In some cases, the condition is diagnosed during routine x-ray imaging, due to a lack of overt symptoms. The most common location for this condition to manifest is the head or neck of the femur or humerus, and the knee joint. If you believe that this Physiopedia article is the primary source for the information you are refering to, you can use the button below to access a related citation statement.When treating hip pain, non-surgical treatments should always be considered first. In some cases, conservative treatments such as rest, activity restriction, physical therapy, and/or pain medication can resolve the pain and swelling. Advanced Imaging helps our doctors better understand what’s going on deep inside your hip socket. We may recommend specialized advanced imaging studies, which are all available at CHOP: If the hip pain or discomfort caused by avascular necrosis does not improve with non-operative treatment, or if your doctor is concerned about further collapse of the ball and worsening of your condition, surgery for AVN may be recommended.A diagnosis of AVN may be suspected after a detailed history and physical examination, and x-rays may be sufficient to confirm the diagnosis. In cases of early AVN, however, x-rays may not show the condition and further imaging may be necessary.

Avascular necrosis (AVN), also known as osteonecrosis, is most common in the femoral head. In early disease the X-ray can be normal, and MRI may be required if the diagnosis is suspected clinically.Study the course material in the free to access tutorials and galleries sections – then sign up to take your course completion assessment. Login or register to get started.

AVN most commonly affects the hips. Eponyms are attributed to AVN of some of the less common sites, for example AVN of the second metatarsal head can be referred to as ‘Freiberg’s infraction, and AVN of the lunate bone can be referred to as ‘Keinbock’s disease’.
X-rays use invisible electromagnetic energy beams to produce images of internal tissues, bones, and organs on film. Standard X-rays are performed for many reasons, including diagnosing tumors or bone injuries.Access your health information from any device with MyHealth. You can message your clinic, view lab results, schedule an appointment, and pay your bill.