特发性髋关节炎诱因——股骨髋臼撞击

临床上可见部分成年人及年轻人表现出髋关节炎症状,近期研究发现股骨髋臼撞击可能是其产生的重要原因.股骨髋臼撞击是由于股骨和髋臼解剖学异常造成两者不相匹配,运动终末期产生异常碰撞所致,患者常诉腹股沟处疼痛,同时伴有髋关节活动范围减小,特异性体检及良好的影像学资料均可呈阳性.引起碰撞原因众多,其机制可分为凸轮碰撞和钳夹碰撞两种.非手术治疗只能暂时缓解症状,不能阻止关节进一步退变;手术治疗可解除碰撞因素,缓解症状,并阻止病变继续发展,早期手术对患者更有利;近期随访表明,术后患者关节功能较术前明显改善,且股骨头缺血坏死等手术并发症发生率极低.     

髋关节撞击综合征的诊断和治疗

目的 探讨髋关节撞击综合征(FAI)的临床诊断和治疗的体会.方法 通过总结2002年以来29例门诊患者和5例手术患者的临床资料,分析该综合征的临床表现,骨科检查的特点以及放射学检查的特征性改变.结果 29例门诊患者中大部分患者起病隐袭,发展缓慢,髋关节的骨科检查可见特征性撞击试验阳性.X线片发现11例股骨头有"枪柄样畸形",20例CE角大于40°,4例髋臼后倾.核磁共振造影检查能够提供准确的盂唇损伤的诊断依据.其中5例患者接受了手术治疗.结论 FAI能够引起髋关节疼痛并导致髋骨关节炎,早期发现是治疗的关键.     

Femoroacetabular impingement: role of imaging

Osteopetrosis is a rare skeletal condition first described by German radiologist Heinrich Albers-Schonberg. The most important technical difficulty is drilling due to hard bone in patients with osteopetrosis; recommendations have been made to use high-speed electric drill bits. But, the unavailability of this special drill bit in most of the centres makes the job more difficult. The study was conducted from 2009 to 2012; the cases are selected from Outpatients Department of Postgraduate Institute of Medical Education and Research. The patients were in the age group of 10–50 years with a mean age of 26 years. Five cases were included in the study: four patients had subtrochanteric fractures, and one had segmental fracture of the humerus. Open reduction and internal fixation was done in all the fractures using metal-cutting drill bit. The use of metal-cutting drill bit in osteopetrosis not only made our job easy but also prevented thermal necrosis of the bone to a large extent. The union rate was 100 % in our series, and there was no infection in any of our cases. In the treatment for fractures in osteopetrosis, the use of a metal-cutting drill bit along with careful attention to drilling technique can help avoid bit breakage and thermal bone injury that may produce ring sequestrum or destroy the already scant osteogenic cells.     

High prevalence of cam deformity in dysplastic hips: A three‐dimensional CT study

Cam deformity could lead to suboptimal articulation by causing secondary femoroacetabular impingement after periacetabular osteotomy; however, the inherent femoral head‐neck morphology in dysplastic hips and the effect of an additional osteoarthritic deformity have not been well described. We compared femoral head‐neck morphology using three‐dimensional imaging of normal and dysplastic hips in pre/early (Tönnis grade 0 and 1) and advanced stage osteoarthritis (Tönnis grade 2). Using computed tomography, we measured the circumferential α‐angle and head‐neck offset ratio in 68 dysplastic hips and 24 normal hips. Locations of the head‐neck junction were represented by the clock position. In the pre/early group, the α‐angle was significantly larger at the anterosuperior and inferior aspects (1, 2, and 5–7 o'clock) and head‐neck offset ratio was smaller at the anterosuperior aspect (2 o'clock) than in the control group. The α‐angle was significantly larger at the anterior aspects (1–4 o'clock) in the advanced group than in the pre/early group. The maximum α‐angle was most commonly found at 2 o'clock (60%, 41/68 hips) in dysplastic hips. The prevalence of cam deformity (maximum α‐angle >55°) was 4.2% (1/24 hips) in the control group, 22% (11/50 hips) in the pre/early group, and 50% (9/18 hips) in the advanced group. Cam deformity, inherent in the pre/early group, was found with relatively high frequency. The higher prevalence in the advanced group reflected degeneration‐modified changes. When performing periacetabular osteotomy, preoperative radiographic assessments should include the femoral head‐neck junction to prevent secondary femoroacetabular impingement, especially in patients with advanced stage osteoarthritis. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1613–1619, 2016.     

Femoroacetabular impingement syndrome--pre-arthritis of the hip

The diagnosis of femoroacetabular impingement (FAI) syndrome is relatively recent. Therefore, the concept of early hip arthritis development is an interesting issue. The assumed prevalence of this disease is rather high and any postponement of necessity to perform total hip arthroplasty (THA) for hip arthritis, as a FAI sequela, should bring benefits to medical care as well as economy. To make an exact diagnosis it is necessary, in addition to essential clinical examination and standard conventional radiography, to carry out MRI that, in indicated cases, is combined with arthrography. Surgical treatment includes extensive procedures, such as controlled surgical dislocation of the hip with modeling of the femoral head and periacetabular osteotomy. In the case of primary surgery for FAI, short- and middleterm results so far obtained are promising, but only long-term results will show whether, and for how many years, this therapy is able to postpone the necessity of THA. For the future, biological therapy using autologous hyaline cartilage transfer will remain a challenge also for this indication.     

Femoroacetabular impingement: a cause for osteoarthritis of the hip

A multitude of factors including biochemical, genetic, and acquired abnormalities may contribute to osteoarthritis of the hip. Although the pathomechanism of degenerative process affecting the dysplastic hip is well understood, the exact pathogenesis for idiopathic osteoarthritis has not been established. Based on clinical experience, with more than 600 surgical dislocations of the hip, allowing in situ inspection of the damage pattern and the dynamic proof of its origin, we propose femoroacetabular impingement as a mechanism for the development of early osteoarthritis for most nondysplastic hips. The concept focuses more on motion than on axial loading of the hip. Distinct clinical, radiographic, and intraoperative parameters can be used to confirm the diagnosis of this entity with timely delivery of treatment. Surgical treatment of femoroacetabular impingement focuses on improving the clearance for hip motion and alleviation of femoral abutment against the acetabular rim. It is proposed that early surgical intervention for treatment of femoroacetabular impingement, besides providing relief of symptoms, may decelerate the progression of the degenerative process for this group of young patients.     

Femoroacetabular impingement caused by a femoral osseous head–neck bump deformity: clinical,radiological, and experimental results

Femoroacetabular impingement is often associated with reduced femoral anteversion or an osseous bump deformity on the femoral head–neck junction. We report prospectively on 17 patients showing an osseous bump at the anterolateral head–neck junction on radiography (22 hips) and typical signs of femoroacetabular impingement on clinical examination. Following three plans of treatment, nine patients (10 hips) underwent nonoperative treatment, and eight patients (12 hips) had surgery. In eight hips with labral defects but minor cartilage damage, the bump was surgically removed via trochanter flip osteotomy. Two hips were treated surgically through an anterior surgical approach without hip dislocation. Four hips with severe signs of osteoarthritis and significantly reduced range of motion underwent total replacement. To elucidate a local osteogenic differential potential, tissue specimens of the perilesional capsule were investigated immunohistochemically. Various antigens and protein synthesis products served to identify osteoblastic and progenitor cells. There was a significant improvement in internal rotation and pain relief in patients who underwent surgical resection of the osseous bump. No avascular osteonecrosis or other significant severe side effects were observed during follow-up. In contrast, no nonoperatively treated patients improved. Furthermore, immunohistochemical studies showed perilesional recruitment of osteoprogenitor cells.     

Femoroacetabular impingement syndrome: a narrative review for the chiropractor

Objective:

To familiarize the chiropractic clinician with the clinical presentation, radiographic features, and conservative versus surgical treatment options for managing femoroacetabular impingement (FAI) syndrome.

Background:

FAI syndrome is a relatively new clinical entity to be described in orthopedics, and has been strongly linked with pain and early osteoarthritis of the hip in young adults. Hip joint radiographs in these patients often appear normal at first—particularly if the clinician is unfamiliar with FAI. The role of conservative therapy in managing this disorder is questionable. Surgical treatment ultimately addresses any acetabular labral or articular cartilage damage, as well as the underlying osseous abnormalities associated with FAI. The most commonly used approach is open surgical hip dislocation; however, more recent surgical procedures also involve arthroscopy.

Conclusion:

In FAI syndrome—a condition unknown to many clinicians (including medical)—chiropractors can play an important role in its diagnosis and referral for appropriate management.     

In vivo hip joint contact distribution and bony impingement in normal and dysplastic human hips

Our objectives were to clarify the 3D articular contact areas of the in vivo normal hip joint and acetabular dysplasia during specific positions using magnetic resonance imaging (MRI), voxel‐based registration, and proximity mapping. Forty‐two normal and 24 dysplastic hips were examined. MRI was performed at four positions: neutral; 45° flexion; 15° extension; and the Patrick position. Femur and pelvis bone models were reconstructed at the neutral position and superimposed over the images of each different position using voxel‐based registration. The inferred cartilage contact and bony impingement were investigated using proximity mapping. The femoral head translated in the anterior or posteroinferior, anterosuperior, and posteroinferior direction from neutral to 45° flexion, 15° extension, and the Patrick position, respectively. Multiple regression analyses showed age, femoral head sphericity, and acetabular sphericity to be associated with higher hip instability. The present technique using subject‐specific models revealed the in vivo hip joint contact area in a population of healthy individuals and dysplastic patients without radioactive exposure. These results can be used for analyzing disease progression in the dysplastic hip and pathogenesis of acetabular labral tear. © 2013 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 31:1611–1619, 2013     

Femoroacetabular cup impingement after resurfacing arthroplasty of the hip

Femoroacetabular cup impingement (FACI), defined as the presence of a bony spur or indentation at the femoral neck corresponding to the abutment site of metallic cup, was observed in 9 (11%) of the 84 hips with contemporary resurfacing arthroplasty of the hip. All FACIs occurred in men after a mean of 14 months (range, 8-24 months) postoperatively. Five patients had persistent groin pain if the hip was moved into flexion, abduction, and external rotation. One patient sustained a late-onset fracture through the femoral neck already weakened by postoperative change of osteonecrosis. Mean postoperative Harris hip score in the FACI group was poorer than that in the non-FACI group (P = .003). Multiple logistic regression analysis showed a significant association of FACI with a low acetabular cup inclination (odds ratio, 1.42; 95% confidence interval, 1.01-1.99; P = .046) and a high cup uncoverage ratio (odds ratio, 1.36; 95% confidence interval, 1.01-1.84; P = .045).     

Femoroacetabular impingement and risk factors: a study of 50 cases

Objective: To study the asphericity of the femoral head in femoroacetabular impingement using the radiological indices alpha angle and triangular index, and correlation with risk factors. Methods: The study was conducted retrospectively from January 2008 to June 2010 on 50 consecutive patients with suspected cam type femoroacetabular impingement of the hip who reported to the orthopaedics outpatients department of the Postgraduate Institute of Medical Education and Research. Ten controls were also used in the study. Radiographs of the affected hip were taken and then the alpha angle and triangular index were measured and correlated with various risk factors. Results: In the anteroposterior view the alpha angle range was from 55° to 106° for the cases and from 54° to 70° for the controls. In the lateral view the range was from 62° to 104° for the cases and from 54° to 62° for the controls. The mean alpha angle in the anteroposterior view was measured as 75°± 10° in the cases and 61°± 6° in the controls, and the mean in the lateral view was 74°± 8° in the cases and 58°± 6° for the controls. The triangular index range in the radiographs was from 1 to 7 in the cases and from 0 to 1 for the controls. The mean triangular index in the radiographs was 2.9 ± 1.2 for the cases and 0.2 ± 0.4 for the controls. Conclusion: There was no significant correlation between the age and gender of the patient and the femoroacetabular impingement. However, there was significant correlation between the body mass index of the patient and the femoroacetabular impingement.     

Experimentally induced cam impingement in the sheep hip

Sheep hips have a natural non‐spherical femoral head similar to a cam‐type deformity in human beings. By performing an intertrochanteric varus osteotomy, cam‐type femoro‐acetabular impingement (FAI) during flexion can be created. We tested the hypotheses that macroscopic lesions of the articular cartilage and an increased Mankin score (MS) can be reproduced by an experimentally induced cam‐type FAI in this ovine in vivo model. Furthermore, we hypothesized that the MS increases with longer ambulatory periods. Sixteen sheep underwent unilateral intertrochanteric varus osteotomy of the hip with the non‐operated hip as a control. Four sheep were sacrificed after 14, 22, 30, and 38‐weeks postoperatively. We evaluated macroscopic chondrolabral alterations, and recorded the MS, based on histochemical staining, for each ambulatory period. A significantly higher prevalence of macroscopic chondrolabral lesions was found in the impingement zone of the operated hips. The MS was significantly higher in the acetabular/femoral cartilage of the operated hips. Furthermore, these scores increased as the length of the ambulatory period increased. Cam‐type FAI can be induced in an ovine in vivo model. Localized chondrolabral degeneration of the hip, similar to that seen in humans (Tannast et al., Clin Orthop Relat Res 2008; 466: 273–280; Beck et al., J Bone Joint Surg Br 2005; 87: 1012–1018), can be reproduced. This experimental sheep model can be used to study cam‐type FAI. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31: 580–587, 2013     

Open‐MRI measures of cam intrusion for hips in an anterior impingement position relate to acetabular contact force

Open MRI in functional positions has potential to directly and non‐invasively assess cam femoroacetabular impingement (FAI). Our objective was to investigate whether open MRI can depict intrusion of the cam deformity into the intra‐articular joint space, and whether intrusion is associated with elevated acetabular contact force. Cadaver hips (9 cam; 3 controls) were positioned in an anterior impingement posture and imaged using open MRI with multi‐planar reformatting. The β‐angle (describing clearance between the femoral neck and acetabulum) was measured around the entire circumference of the femoral neck. We defined a binary “MRI cam‐intrusion sign” (positive if β < 0°). We then instrumented each hip with a piezoresistive sensor and conducted six repeated positioning trials, measuring acetabular contact force (F). We defined a binary “contact‐force sign” (positive if F > 20N). Cam hips were more likely than controls to have both a positive MRI cam‐intrusion sign (p = 0.0182, Fisher's exact test) and positive contact‐force sign (p = 0.0083), which represents direct experimental evidence for cam intrusion. There was also a relationship between the MRI cam‐intrusion sign and contact‐force sign (p = 0.033), representing a link between imaging and mechanics. Our findings indicate that open MRI has significant potential for in vivo investigation of the cam FAI mechanism. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:205–216, 2016.     

Femoroacetabular impingement and comparison of radiological indexes: a study on 50 cases

To study the asphericity of femoral head in femoroacetabular impingement using radiological indices such as alpha angle and triangular index, and to compare the alpha angle and triangular index measured in the radiograph and MRI. The study was conducted prospectively from January 2008 to June 2009 on 50 consecutive patients of suspected cam-type FAI hip, reporting to orthopedics outpatients department of Postgraduate Institute of Medical Education and Research. Radiograph of the affected hip was taken, and then alpha angle and triangular index are measured and compared. The mean alpha angle in anteroposterior view was measured as 75° ± 10°, and the mean in lateral view was 740 ± 80. In MRI the mean alpha angle was 79° ± 9°. The mean triangular index in radiograph was 2.9 ± 1.2. In MRI the mean triangular index was 2.6 ± 0.8. Frog-leg lateral view is sufficient for the diagnosis of the cam-type femoroacetabular impingement. But MRI is required in cases, where surgical intervention is planned to rule out other pathological condition and for decision making.     

Magnetic resonance arthrography of labral disorders in hips with dysplasia and impingement

Despite the fact that classic studies on osteoarthritis of the hip have shown the periphery of the hip to be prone to degeneration, it was not until recently that an abnormal acetabular labrum has been associated with osteoarthritis. This study was designed to determine whether magnetic resonance arthrography can show differences in disorders of the labrum (tears, size, ganglion formation) expected in symptomatic patients with developmental dysplasia of the hip and anterior femoroacetabular impingement. Fourteen patients in each group were evaluated preoperatively not only clinically but also with conventional radiographs and magnetic resonance arthrographs. In both conditions, disorders of the labrum localized identically with a predilection to the anterosuperior quadrant of the acetabulum. Labral tears were observed in nine hips of each group. The labrum was enlarged in 12 hips with dysplasia but in none of the hips with impingement. Ganglion formation in the periacetabular area was seen in 10 hips with dysplasia and three hips with impingement. These findings provide evidence that the anterosuperior acetabulum represents the initial fatiguing site of the hip under both conditions. Based on these data, the size of the labrum and the presence of soft tissue ganglia seem to be good predictors for the presence of developmental dysplasia, whereas the presence of tears did not differentiate between conditions. The capability of magnetic resonance arthrography to show these differences in labral disorders suggests this method is a helpful diagnostic tool that can aid in defining the most appropriate treatment strategy.     

Gender differences in 3D morphology and bony impingement of human hips

For the proper diagnosis or treatment of hip joint disorders caused by anatomical abnormalities, the normal hip joint morphology must be studied to understand its influence on the maximum range of motion (ROM) until bony impingement by focusing on gender differences. Acetabular and femoral morphologies were analyzed from 3D CT images of 106 normal hip joints from elderly men (n = 36 joints) and women (n = 70 joints), and measurements of ROM until bony impingement were made in four directions (flexion, extension, and external and internal rotation at 90° flexion) using surface models of the pelvis and femur reconstructed from the CT data. Gender differences were found not only in joint orientation, including anteversion and inclination of the acetabulum and femoral neck anteversion, but also in the shape around the joint, including the acetabular rim and the femoral neck. This ROM study also showed gender differences in all four standard directions. In conclusion, significant gender differences were observed in the acetabular and femoral morphology, which led to significant gender differences in ROM until bony impingement. © 2010 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 29:333–339, 2011