Osteonecrosis of the femoral head (ONFH), also known as ischemic necrosis of the femoral head (AVNFH), is a common disease in orthopedics. The Expert Consensus on the Diagnosis and Treatment of Femoral Head Necrosis (2012 Edition) was launched after discussion, modification and supplementation of the Expert Recommendations on the Diagnosis and Treatment of Femoral Head Necrosis.
I. Overview.
The definition of osteoclastic necrosis of the femoral head (ONFH) by ARCO and AAOS: ONFH is a disease in which the blood supply to the femoral head is interrupted or damaged, causing death of bone cells and bone marrow components and subsequent repair, which then leads to structural changes of the femoral head and collapse of the femoral head, causing joint pain and joint dysfunction in patients, and is a common and intractable disease in the field of orthopedics.
ONFH can be divided into two categories: traumatic and non-traumatic. The former is mainly caused by hip trauma such as femoral neck fracture and hip dislocation, while the latter is mainly caused by corticosteroid application, alcoholism, decompression sickness, sickle cell anemia and idiopathic in China.
Second, the diagnostic criteria.
Referring to the diagnostic criteria proposed by the Japanese Ministry of Health and Welfare Osteonecrosis Research Society (JIC) and Mont, the following diagnostic criteria were formulated in China.
1.Clinical symptoms, signs and history Arthralgia mainly in the groin, hip and thigh area, occasionally accompanied by knee pain and limited internal rotation of the hip joint, often with a history of hip trauma, corticosteroid application, alcoholism and occupational history such as divers.
2.MRI T1WI shows band-like low signal or T2WI shows double line sign.
3.X-ray film changes Common sclerosis, cystic changes and crescentic signs and other appearances.
4.CT scan changes: sclerotic bands around necrotic bone, repaired bone, or subchondral bone fracture.
5.Nuclear bone scan shows perfusion defect (cold area) at the initial stage; necrosis repair stage shows cold area in hot area, i.e. “bagel-like” changes.
6. Bone biopsy shows more than 50% of osteocyte vacuoles in the trabeculae and involvement of multiple adjacent trabeculae, with bone marrow necrosis.
Expert advice: meeting two or more criteria can confirm the diagnosis: except for 1, 2, 3, 4 and 6 can be diagnosed by meeting one of them.
Third, differential diagnosis.
Patients with similar clinical symptoms, x-ray changes or MRI changes should be differentiated.
1, intermediate and advanced hip osteoarthritis It may be confused when the joint space is narrowed and subchondral cystic changes appear, but its CT shows sclerosis with cystic changes and Mill changes are mainly low signal, which can be differentiated accordingly.
2, acetabular dysplasia secondary to osteoarthritis Femoral head wrapping incomplete, narrowing and loss of joint space, osteosclerosis, cystic changes, and similar changes in the corresponding area of the acetabulum, easy to distinguish.
3, ankylosing spondylitis involving the hip joint Common in adolescent males, mostly bilateral sacroiliac joint involvement, which is characterized by HLA-B27 positive, the femoral head remains round, but the joint space is narrowed, disappeared or even fused, easy to distinguish. Some patients with long-term application of corticosteroids can be combined with ONFH, the head of the femur can appear collapse but often not heavy.
4, rheumatoid arthritis Most commonly seen in women, the femoral head remains round, but the joint space becomes narrow and disappears; common femoral head joint surface and acetabular bone erosion, easy to distinguish.
5, chondroblastoma within the femoral head MRI T2WI shows lamellar high signal, CT scan shows irregular osteolytic destruction.
6.Transient osteoporosis (ITOH) It can be seen in middle-aged and young people, and is a temporary painful bone marrow edema; radiographs show reduced bone mass in the femoral head, neck and even rotor: MRI shows uniform low signal in T1WI and high signal in T2WI, which can range to the femoral neck and rotor, without banded low signal, and can be distinguished from ONFH. The lesion can be dissipated within 3-12 months.
7, subchondral incomplete fracture Most commonly seen in elderly patients over 60 years old, without obvious history of trauma, showing sudden onset of hip pain, inability to walk, and limited joint movement. x-ray shows slightly flattening of the upper outer femoral head, T1 and T2-weighted phase of MRI shows subchondral low signal lines, surrounding bone marrow edema, and T2 lipid suppression phase shows lamellar high signal.
8, hyperpigmented villous nodular synovitis Most often occurs in the knee joint, and hip joint involvement is rare. CT and radiographs may show cortical bone erosion of the femoral head, neck or acetabulum, and mild to moderate narrowing of the joint space. MRI shows extensive synovial hypertrophy with a uniform distribution of low or moderate signal.
9, synovial herniation pit This is a benign lesion of synovial tissue proliferation invading the cortex of the femoral neck, MRIT, T1WI low signal, T2WI high signal small circular lesion, located in the upper cortex of the femoral neck, usually asymptomatic.
10, bone infarction Osteonecrosis occurring in the long bone stem has different imaging manifestations at different times, MRI manifestations are: ① acute stage: the center of the lesion shows equal or slightly high signal with normal bone marrow in T1WI, high signal in T2WI, long T1 and long T2 signal at the edge; ② subacute stage: the center of the lesion shows similar or slightly low signal with normal bone marrow in T1WI, similar or slightly high signal with normal bone marrow in T2WI, and long T1 and long T2 signal at the edge. (2) subacute stage: the center of the lesion showed similar or slightly low signal in T1WI and similar or slightly high signal in T2WI, with long T1 and long T2 signal at the edges.
Fourth, staging and staging.
Once the diagnosis of femoral head necrosis is confirmed, staging should be made to guide the development of a reasonable treatment plan and accurately determine the prognosis. Experts recommend mainly using ARCO staging and Steinberg staging, with reference to Ficat staging. Regarding the staging criteria of femoral head necrosis, domestic experts refer to the aforementioned staging and JIC staging, and put forward improved staging, which can be referred to.
Fifth, the treatment of femoral head necrosis.
There are many treatment methods for femoral head necrosis, and the development of a reasonable treatment plan should take into account factors such as staging, necrosis volume, joint function, and patient age, occupation and compliance with joint preservation treatment.
(i) Non-surgical treatment.
It is mainly applied to patients with early stage of femoral head necrosis.
1.Protective weight-bearing The use of double crutches can effectively reduce pain, but the use of wheelchairs is not advocated.
2.Medication Non-steroidal anti-inflammatory drugs, low-molecular heparin, alendronate sodium, etc. have certain efficacy, and vasodilator drugs also have certain efficacy.
3.TCM treatment Take the holistic view of Chinese medicine as the guide, follow the basic principles of “combining movement and static, tendons and bones, internal and external treatment, and cooperation between doctors and patients”, and emphasize early diagnosis, combination of disease and evidence, and early standardized treatment. For patients in the subclinical stage, Chinese herbal medicines are mainly used to activate blood circulation and resolve blood stasis, supplemented by removing phlegm and dampness and tonifying kidney and bone, which can promote necrosis repair and prevent or reduce collapse; for femoral head necrosis with pain and other symptoms before collapse, on the basis of protective weight-bearing, Chinese herbal medicines are used to activate blood circulation and resolve blood stasis, promote water and dampness, which can relieve pain and improve joint function; for post-collapse femoral head necrosis, together with surgical repair surgery, can improve surgical effect.
4.Physical therapy includes extracorporeal shock wave, high frequency electric field, hyperbaric oxygen, magnetic therapy, etc., which are beneficial to relieve pain and promote bone repair.
5.Braking and appropriate traction are suitable for ARCO stage I and II cases.
(ii) Surgical treatment.
Most patients with ONFH will face surgical treatment, which includes two major types of surgeries: preserving the patient’s own femoral head and artificial hip arthroplasty. Femoral head preservation surgery includes medullary core decompression, bone grafting, osteotomy, etc. It is suitable for patients with ARCO stages I and II and IIIa and IIIb, and patients with ONFH with 15% or more necrosis volume. If the method is appropriate, artificial joint replacement can be avoided or postponed.
1, femoral head medullary core decompression The history of medullary core decompression is long and the efficacy is certain. At present, it can be divided into fine needle drilling decompression surgery and coarse channel medullary decompression surgery. The difference mainly lies in the different diameter of the decompression channel. The diameter of the orifice of multi-needle drilling decompression is 3mm, 3.5mm or 4mm; the diameter of the orifice of coarse channel medullary core decompression is 6mm or more. Experts recommend using a fine needle (about 3mm in diameter) and drilling multiple holes under fluoroscopic guidance. It can be combined with implant materials. Medullary core decompression combined with stem cell transplantation (or concentrated autologous bone marrow single nucleus cell transplantation) is currently a Class III medical technology under the control of the Ministry of Health and is not widely performed in China. Based on the good results of clinical application in some domestic units, experts suggest that it should be applied with caution after the establishment of a multicenter long-term follow-up reporting system with large samples.
2.Bone grafting without hemorrhage There are more applications such as trans-femoral rotor decompression bone grafting and trans-femoral head neck bulb decompression bone grafting. The bone grafting methods include compression bone grafting, support bone grafting, etc. The applied bone grafting materials include autologous cancellous bone, allograft bone and bone replacement material.
3.Osteotomy The necrotic area is moved out of the weight-bearing area of the femoral head. The osteotomies used in clinical practice include internal or external osteotomy and transfemoral rotational osteotomy. Osteotomy is chosen on the principle of not altering the femoral medullary cavity.
4.Autogenous bone graft with blood transport Autogenous bone graft can be divided into periprosthetic bone flap graft and fibula graft. There are various choices of periprosthetic bone flaps with vascular tips: ① iliac (membrane) flap transfer with ascending branch of the lateral femoral vessel; ② greater trochanteric flap transfer with ascending branch of the lateral femoral vessel; ③ greater trochanteric flap transfer with transverse branch of the lateral femoral vessel; ④ iliac (membrane) flap transfer with deep vascular tip of the rotating iliac; ⑤ the whole femoral head or even part of the femoral neck is involved, the transverse branch of the greater trochanteric flap can be combined with iliac (membrane) flap of ascending branch to reconstruct the femoral head (neck); (6) deep-branched greater trochanteric flap of the medial vessels of the rotating femur and deep-branched iliac flap of the superior gluteal vessels in the posterior approach to the hip joint; (7) bone flap (column) with the femoral squared tip: periprosthetic bone flap with vascularized tip is less invasive, more effective, and easy to grasp the surgical method, which is recommended: to increase the strong support within the femoral head, tantalum can be jointly implanted when applying periprosthetic bone flap with vascularized tip Metal rods can effectively avoid postoperative femoral head collapse, which has good short-term efficacy and long-term efficacy is yet to be determined: the surgical effect of anastomotic vascularized fibula graft is also more certain: if this method is properly applied, the efficacy is better and it is recommended: the choice of various vascularized bone flaps can be considered according to their advantages and disadvantages, the operator’s proficiency and other factors.
5.Artificial joint replacement Once the femoral head has collapsed heavily (ARCO stage IIIc, stage IV), and there is serious loss of joint function or pain, artificial joint replacement should be chosen: it is generally believed that the medium and long-term efficacy of non-cemented or hybrid prosthesis is better than cemented prosthesis; artificial joint replacement for femoral head necrosis is different from joint replacement for other diseases, and some related issues should be noted: ① Patients long-term application of corticosteroids, or have underlying disease need to continue treatment, so the infection rate is increased; ② long-term non-weight-bearing, osteoporosis and other reasons lead to easy penetration of the prosthesis into the acetabulum; ③ had performed surgery to preserve the femoral head, will bring a variety of technical difficulties; ④ hormonal ONFH, alcoholic ONFH is not only the lesion of the femoral head, its surrounding that is, the whole body bone has also been damaged: Therefore, hormonal ONFH, alcoholic ONFH line artificial joint replacement of long-term results, may not be as osteoarthritis or traumatic ONFH.
Sixth, the principles of treatment plan selection.
The choice of treatment plan should be based on the stage of necrosis, the patient’s age, the patient’s compliance with joint preservation treatment and other comprehensive considerations.
(A) the choice of treatment for different stages of femoral head necrosis.
For non-traumatic ONFH cases, if the diagnosis is confirmed on one side, the contralateral side should be highly suspected and bilateral MRI examination is advisable, and follow-up every 3-6 months is recommended.
Treatment of asymptomatic ONFH is recommended for ONFH with large necrotic volume (>30%) and necrosis located in the weight-bearing zone should be treated aggressively and should not wait for symptoms to appear: a combination of medullary core decompression or non-surgical treatment tools is recommended.
ARCO stage I: if it belongs to asymptomatic, non-weight-bearing area, lesion area <15%, it can be closely observed and regularly followed up; those with symptoms or lesions >15% should be actively treated with non-surgical treatment such as lower limb traction and drugs, and also feasible to preserve joint surgical treatment, and medullary core decompression (stem cell transplantation or concentrated autologous bone marrow single nucleus cell transplantation) is recommended.
ARCO Stage II: In cases where the femoral head has not yet collapsed, marrow core decompression (stem cell transplantation or concentrated autologous bone marrow single nucleus cell transplantation), autologous bone graft with hematopoiesis, bone graft without hematopoiesis (15% < necrosis < 30%) are recommended.
ARCO stage IIIa, IIIb: various autologous bone grafts with hematopoiesis are recommended.
ARCO stage IIIc, IV: In ONFH cases, if the symptoms are mild and the age is young, joint preservation surgery can be chosen and bone grafting with vascular autologous bone (such as greater trochanteric bone flap with vascular tip combined with iliac bone graft, etc.) is recommended; artificial total hip replacement is recommended for severe femoral head collapse.
Femoral head preservation surgery can often be performed with a combination of one or more of several procedures, and a combination is recommended, such as medullary core decompression with bone flap grafting. Non-surgical treatment should also be within the scope of comprehensive treatment.
(B) age factors and the choice of treatment options.
In young and middle-aged ONFH cases, due to the greater activity of the patient, treatment options should be chosen that can preserve the head and not adversely affect the possible arthroplasty of the human ding: recommended: medullary core decompression (stem cell transplantation), autologous bone grafting with blood flow, bone grafting without blood flow (15% < necrosis range < 30%).
In middle-aged ONFH cases, if in the earlier stages of ONFH (no collapse), every effort should be made to preserve the head, such as medullary core decompression, bone grafting with or without blood transport; if in the middle and late stages of ONFH, the patient’s subjective wishes and technical conditions should be combined to choose head-preserving treatment or human ding arthroplasty. When deciding to perform artificial joint replacement, preoperative prosthesis selection should fully consider the possibility of secondary revision.
For elderly (>55 years old) ONFH cases, artificial total hip arthroplasty is recommended.
For elderly ONFH cases, it depends on the patient’s original daily activity status, hip bone quality, and life expectancy. It is recommended to perform bipolar (tripolar) artificial femoral head replacement or artificial total hip arthroplasty.
VII. Efficacy evaluation and rehabilitation exercise.
The evaluation of the efficacy of ONFH can be divided into clinical evaluation and imaging evaluation. Clinical evaluation adopts hip function score (such as Harris score, WOMAC score, Chinese Medical Association Orthopedic Branch percentage method for efficacy evaluation, etc.), and should be evaluated on a case-by-case basis according to the same stage, similar necrosis area, and the same treatment method. Gait analysis information is also recommended. Imaging evaluation can be applied to X-ray films with concentric circle templates to observe femoral head shape, joint space and acetabular changes. MRI data should be available for the evaluation of lesions up to stage II. For patients with hemorrhagic bone graft, DSA should be performed and used to evaluate hemorrhagic recovery. Experts recommend the establishment of case files for ONFH patients to accumulate more valuable information, which can help evaluate the efficacy of different etiologies, different necrosis periods, different ages, and different treatment methods, and help reach a consensus on more standardized treatment of ONFH.
Rehabilitation exercise can prevent wasting muscle atrophy in patients with ONFH, and is an effective means to promote early recovery of function. The functional exercise should be mainly active, supplemented by passive, from small to large, from less to more, gradually increasing, and according to the stage of ischemic necrosis of femoral head, treatment modality, hip function score and gait analysis data, choose the appropriate exercise method.
(1) Reclining leg lift method: lie on your back, lift the affected leg, flex the hip and knee 900, and repeat the action. 200 times per day, divided into 3-4 times. Apply to: ONFH conservative treatment and post-surgical treatment of bedridden period.
(2) Sitting partition: sit on a chair, hands on knees, feet shoulder-width apart, left leg to the left, right leg to the right while fully abducting and adducting. 300 times daily in 3 to 4 sessions. Application: ONFH conservative treatment and post-surgical treatment can be partially weight-bearing period.
(3) Standing leg lift method: hold the fixation with hands, keep the body upright, lift the affected leg so that the body is at a right angle to the thigh, flex the hip and knee 90 degrees, and repeat the action. 300 times daily, in 3~4 times. Apply to: ONFH conservative treatment and surgical treatment can be part of the weight-bearing period.
(4) support squatting method: hand holding a fixed object, body upright, feet shoulder-width apart, squatting and then stand up, the action is repeated. 300 times a day, in 3 to 4 times. Application: ONFH conservative treatment and surgical treatment can be fully weight-bearing period.
(5) Internal rotation and abduction method: hand holding a fixed object, legs are doing full internal rotation, abduction and circle movement. 300 times daily, divided into 3~4. Apply to: ONFH conservative treatment and surgical treatment can be fully weight-bearing period.
(6) Adhere to the training of walking with crutches or cycling exercise. Used in: ONFH conservative treatment and surgical treatment can be fully weight-bearing period.