The hereditary predisposition to hip osteoarthritis and its association with abnormal joint morphology.

OBJECTIVE: Genetic factors and abnormalities of joint morphology are important in the aetiology of hip osteoarthritis (OA). The extent to which genetic influences are manifest through joint morphology has undergone limited investigation. Using a cohort with an hereditary predisposition to end-stage hip OA and a control group with no inherited risk, we aimed to identify associations with abnormal joint morphology and clinical features. DESIGN: One hundred and twenty-three individuals (mean age 52 years) with a family history of total hip arthroplasty (THA) (termed 'sibkids') were compared with 80 spouse controls. Morphology was assessed using standardised radiographs and cam, dysplasia, and pincer deformities defined. Regression modelling described the association of cohort with abnormal joint morphology, adjusting for confounders [age, gender, body mass index (BMI), OA, and osteophyte]. RESULTS: Sibkids had an odds ratio of 2.1 [95%confidence interval (CI) 1.3-3.5] for cam deformity. There were no differences in the prevalence of dysplasia or pincer deformities. In both groups, hips with cam deformities or dysplasia were more likely to have clinical features than normal hips [odds ratio (OR) 4.46 (1.8-11.3), and 4.40 (1.4-14.3) respectively]. Pincer deformity was associated with positive signs in the sibkids but not in the controls (OR 3.0; 1.1-8.2). DISCUSSION: After adjustment for confounders that cause secondary morphological change, individuals with an hereditary predisposition to end-stage hip OA had a higher prevalence of morphological abnormalities associated with hip OA. Sibkids were more likely to demonstrate clinical features in the presence of pincer deformity, suggesting that the genes are acting not only through abnormal morphology but also through other factors that influence the prevalence of pain.

Genetic predisposition to the presence and 5-year clinical progression of hip osteoarthritis.

OBJECTIVE: Genetic factors are important in the aetiology of hip osteoarthritis (OA), but studies are limited by cross-sectional design and poor association with clinically important disease. Identifying cohorts with progressive OA will facilitate development of OA biomarkers. Using a middle-aged cohort with genetic predisposition to hip OA and a control group, we compared the prevalence of clinical and radiographic hip OA and incidence of progression over 5 years. DESIGN: 123 individuals (mean age 52 years) with a family history of total hip arthroplasty (THA) ('sibkids') were compared with 80 (mean age 54 years) controls. The prevalence of radiographic OA [scored according to Kellgren & Lawrence (K&L)], clinical features, and incidence of clinical progression over a 5-year period were compared. A multivariate logistic regression model was used to adjust for confounders. RESULTS: Sibkids had odds ratios (ORs) of 2.7 [95% confidence interval (CI) 1.1-6.3, P = 0.02] for hip OA (K&L grade ≥2), 3.4 (1.4-8.4, P = 0.008) for clinical signs, and 2.1 (0.8-5.8, P = 0.14) for signs and symptoms. Over 5 years, sibkids had ORs of 4.7 (1.7-13.2, P = 0.003) for the development of signs, and 3.2 (1.0-10.3, P = 0.047) for the development of signs and symptoms. DISCUSSION: Compared to a control group and after adjustment for confounders, individuals with genetic predisposition to end-stage hip OA have higher prevalence of OA, clinical features, and progression. In addition to structural degeneration, the inherited risk may include predisposition to pain. Genetically-loaded cohorts are useful to develop hip OA biomarkers, as they develop progressive disease at a young age.

Getting to the heel of the problem: plantar fascia lesions.

Heel pain is a frequent disabling symptom. Clinical diagnosis is often difficult with a large range of possible diagnoses. Lesions of the plantar fascia form an important group. We present a review describing the common lesions of the plantar fascia, including plantar fasciitis, plantar fascia rupture, plantar fibromatosis, and plantar xanthoma, and illustrate them with appropriate magnetic resonance imaging (MRI) and ultrasound imaging. We also address foreign-body reactions, enthesopathy, and diabetic fascial disease.

The use of beam angulation to overcome anisotropy when viewing human tendon with high frequency linear array ultrasound.

Anisotropy is the property of tendons, nerves and muscles to vary in their ultrasound appearance depending on the angle of insonation of the incident ultrasound beam. Loss of reflectivity in tendons may also denote underlying disease. We describe beam angulation, a simple technique available with most modern ultrasound machines, which allows the operator to overcome the potential pitfall of anisotropy in ultrasound assessment of peripheral tendons.

Power Doppler ultrasound of rheumatoid synovitis: quantification of therapeutic response.

The aim of this study is to quantify power Doppler assessment of therapeutic response in rheumatoid synovitis. 13 patients (6 male, 7 female) with rheumatoid arthritis, who had an acute exacerbation of small joint synovitis in the hands, were examined with quantitative power Doppler, before and after intravenous corticosteroid treatment. All patients were examined by a single radiologist, using an ATL HDI 5000 ultrasound machine (ATL, Boswell). The images were analysed using a specially developed software package (HDI Lab), which quantifies power Doppler signal. All patients improved clinically following treatment, which was reflected in functional disability scores, and in the C-reactive protein levels and erythrocyte sedimentation rate. In all cases, there was a significant decrease in synovial vascularity as measured by the mean amplitude of signal on quantitative power Doppler. Quantitative power Doppler may allow objective assessment of treatment in small joint synovitis.

MRI after operative reduction for developmental dysplasia of the hip.

We performed MRI on 13 infants after operative reduction for developmental dysplasia of the hip (DDH). Using an axial gradient-echo sequence, MRI accurately depicted the acetabular anatomy and confirmed adequate reduction in 12 patients. The one patient with redislocation after surgery was correctly identified. MRI can be carried out quickly, inexpensively and without risk of radiation and is the investigation of choice to confirm adequate reduction in DDH.

Genetic influences in the aetiology of tears of the rotator cuff. Sibling risk of a full-thickness tear.

From a retrospective, cohort study of 205 patients diagnosed with full-thickness tears of the rotator cuff, we determined, using ultrasound, the prevalence of such tears in their 129 siblings. Using 150 spouses as controls, the relative risk of full-thickness tears in siblings versus controls was 2.42 (95% CI 1.77 to 3.31). The relative risk of symptomatic full-thickness tears in siblings versus controls was 4.65 (95% CI 2.42 to 8.63). The significantly increased risk for tears in siblings implies that genetic factors play a major role in the development of full-thickness tears of the rotator cuff.

Protocol for the Femoroacetabular Impingement Trial (FAIT): a multi-centre randomised controlled trial comparing surgical and non-surgical management of femoroacetabular impingement.

AIMS: Femoroacetabular Junction Impingement (FAI) describes abnormalities in the shape of the femoral head-neck junction, or abnormalities in the orientation of the acetabulum. In the short term, FAI can give rise to pain and disability, and in the long-term it significantly increases the risk of developing osteoarthritis. The Femoroacetabular Impingement Trial (FAIT) aims to determine whether operative or non-operative intervention is more effective at improving symptoms and preventing the development and progression of osteoarthritis. METHODS: FAIT is a multicentre superiority parallel two-arm randomised controlled trial comparing physiotherapy and activity modification with arthroscopic surgery for the treatment of symptomatic FAI. Patients aged 18 to 60 with clinical and radiological evidence of FAI are eligible. Principal exclusion criteria include previous surgery to the index hip, established osteoarthritis (Kellgren-Lawrence ≥ 2), hip dysplasia (centre-edge angle < 20°), and completion of a physiotherapy programme targeting FAI within the previous 12 months. Recruitment will take place over 24 months and 120 patients will be randomised in a 1:1 ratio and followed up for three years. The two primary outcome measures are change in hip outcome score eight months post-randomisation (approximately six-months post-intervention initiation) and change in radiographic minimum joint space width 38 months post-randomisation. ClinicalTrials.gov: NCT01893034. Cite this article: Bone Joint Res 2014;3:321-7.

Non-invasive imaging of cartilage in early osteoarthritis.

Treatment for osteoarthritis (OA) has traditionally focused on joint replacement for end-stage disease. An increasing number of surgical and pharmaceutical strategies for disease prevention have now been proposed. However, these require the ability to identify OA at a stage when it is potentially reversible, and detect small changes in cartilage structure and function to enable treatment efficacy to be evaluated within an acceptable timeframe. This has not been possible using conventional imaging techniques but recent advances in musculoskeletal imaging have been significant. In this review we discuss the role of different imaging modalities in the diagnosis of the earliest changes of OA. The increasing number of MRI sequences that are able to non-invasively detect biochemical changes in cartilage that precede structural damage may offer a great advance in the diagnosis and treatment of this debilitating condition.

Localized cartilage assessment with three-dimensional dGEMRIC in asymptomatic hips with normal morphology and cam deformity.

BACKGROUND: Cam deformities cause femoroacetabular impingement and damage the acetabular labral-chondral complex. The aims of this study were to investigate the potential of delayed gadolinium-enhanced magnetic resonance imaging of cartilage (dGEMRIC) to detect cartilage disease in asymptomatic hips with cam deformities compared with morphologically normal hips, establish whether dGEMRIC could identify advanced disease in hips with positive clinical findings, and establish whether cartilage damage correlated with the severity of the cam deformity. METHODS: Subjects were recruited from a prospective study of individuals with a family history of osteoarthritis and their spouses who served as control subjects. Their symptoms and impingement test results were recorded. Asymptomatic hips with normal radiographic joint-space width were placed in a subgroup according to the presence of a cam deformity and the impingement test result. dGEMRIC was performed on a 3-T system, studying two regions of interest: the anterosuperior aspect of the acetabular cartilage (T1(acet)) and the total femoral and acetabular cartilage (T1(total)). The ratio T1(acet)/T1(total) gave the relative glycosaminoglycan content in the anterosuperior aspect of the acetabular cartilage. The cohort was placed in subgroups by joint morphology, impingement test status, and genetic predisposition; the mean T1 scores were compared, and the alpha angle and T1 were correlated. RESULTS: Of thirty-two subjects (mean age, fifty-two years), nineteen had cam deformities. Hips with a cam deformity had reduced acetabular glycosaminoglycan content compared with normal hips (mean T1(acet)/T1(total), 0.949 and 1.093, respectively; p = 0.0008). Hips with a positive impingement test result had global depletion of glycosaminoglycan compared with hips with a negative result (mean T1(total), 625 ms versus 710 ms; p = 0.0152). T1(acet) inversely correlated with the magnitude of the alpha angle (r = -0.483, p = 0.0038), suggesting that the severity of cartilage damage correlates with the magnitude of the cam deformity. All of these differences occurred irrespective of genetic predisposition. CONCLUSIONS: The dGEMRIC technique can detect cartilage damage in asymptomatic hips with cam deformities and no radiographic evidence of joint space narrowing. This damage correlates with cam deformity severity. Further study of the application of dGEMRIC as an imaging biomarker of early osteoarthritis is justified to validate its prognostic accuracy, identify subjects for clinical trials, and evaluate the effectiveness of surgical procedures.

Ultrasound of the small joints of the hands and feet: current status.

The aim of this article was to review the current status of ultrasound imaging of patients with rheumatological disorders of the hands and feet. Ultrasound machines with high-resolution surface probes are readily available in most radiology departments and can be used to address important clinical questions posed by the rheumatologist and sports and rehabilitation physician. There is increasing evidence that ultrasound detects synovitis that is silent to clinical examination. Detection and classification of synovitis and the early detection of bone erosions are important in clinical decision making. Ultrasound has many advantages over other imaging techniques with which it is compared, particularly magnetic resonance. The ability to carry out a rapid assessment of many widely spaced joints, coupled with clinical correlation, the ability to move and stress musculoskeletal structures and the use of ultrasound to guide therapy accurately are principal amongst these. The use of colour flow Doppler studies provides a measure of neovascularisation within the synovial lining of joints and tendons, and within tendons themselves, that is not available with other imaging techniques. Disadvantages compared to MRI include small field of view, poor image presentation, and difficulty in demonstrating cartilage and deep joints in their entirety. Contrast-enhanced magnetic resonance provides a better measure of capillary permeability and extracellular fluid than does ultrasound. The ability to image simultaneously multiple small joints in the hands and feet and their enhancement characteristics cannot be matched with ultrasound, though future developments in 3-D ultrasound may narrow this gap. Magnetic resonance provides a more uniform and reproducible image for long-term follow-up studies.

Imaging in shoulder disorders.

Clinical assessment of the patient with shoulder symptoms can usually localize the cause to one of a few syndromes, each associated with specific imaging questions. MRI is used as the primary form of investigation for recurrent dislocation, SLAP lesions and PSI, as well as articular cartilage, synovial disease, tumours and infection. Ultrasound plays the leading role in impingement, acromioclavicular disease, dynamic assessment and guided therapy. Both techniques are reported to play a role in adhesive capsulitis. In our hospital, approximately four times as many shoulder ultrasound examinations as shoulder MRI are carried out, but elsewhere these proportions will vary according to the prevalence of clinical syndromes in the population being treated.

Posteromedial subtalar coalition: imaging appearances in three cases.

OBJECTIVE: To define the imaging appearances in three cases of posteromedial subtalar coalition. DESIGN: Three patients who presented with hindfoot pain were found to have non-osseous coalition involving the posteromedial hindfoot. This entity is distinct from conventional middle facet coalition as the sustentaculum is uninvolved. RESULTS: Plain radiographs, available in two cases, demonstrated subtle irregularity of the posterior facet. MRI (three cases) demonstrated a mixed bony and cartilaginous mass lying posterior to the sustentaculum. There was trabecular oedema within the mass and adjacent talus, and narrowing of the space between the middle and posterior facets. Prominence and dilatation of the posterior tibial veins with tenosynovitis of the adjacent tibialis posterior tendon was seen. CT demonstrated the bony mass but did not detect the adjacent bony oedema. CONCLUSION: Posteromedial subtalar coalition may present with hindfoot pain and stiffness. The presence of a pseudarthrosis posterior to a normal middle facet is characteristic. The abnormality can be difficult to detect on plain radiographs.

Imaging assessment of anterior knee pain and patellar maltracking.

Anterior knee pain is a common complaint in the orthopaedic clinic. The differential diagnosis is wide and the principal goal of initial assessment is to detect remediable causes. The majority of patients do not have a specific disease and increasingly interest has focused on the role of patello-femoro-tibial morphology and of patellar maltracking in the aetiology of anterior knee pain. Classification in this group of patients is poor and there is no uniform agreement on which patient groups benefit from treatment and which treatment is best. Much of the literature involves relatively small numbers of patients, is poorly controlled and there is little agreement on outcome measures. The purpose of this review is to outline the current status of the imaging assessment of recalcitrant anterior knee pain with particular reference to patellar maltracking.

Imaging of plant-thorn synovitis.

We describe a case of plant-thorn synovitis of the elbow resulting from a thorn injury. This caused recurrent pain and swelling of the elbow over a 3-month period. A magnetic resonance imaging examination was initially requested to exclude septic arthritis, and demonstrated a joint effusion, synovitis, and a 2-cm linear opacity embedded in the synovium. Ultrasound was performed prior to surgery to confirm these findings and provide accurate localization of the thorn fragment, later removed at surgery. To our knowledge this is the first example of this condition that has been confirmed by radiological imaging prior to surgery.

The role of MRI in the assessment of scaphoid fracture healing: a pilot study.

Twenty-two patients with fracture of the scaphoid treated by cast immobilisation underwent clinical examination, radiography and MR scanning 6 weeks after injury. On clinical and plain radiographic criteria alone, 12 patients were considered sufficiently healed to warrant mobilisation. The remaining 10 patients were considered unhealed and were immobilised for a further period. A musculoskeletal radiologist, blinded to the clinical diagnosis, reviewed the MRI scans. Of the 10 patients considered unhealed, 5 had the MR appearances of a united fracture, based on normal marrow signal across the fracture line on T1-weighted images. Of the 12 patients deemed to have united, union could be confirmed by MRI criteria in only 5, but all 12 were healed at 1 year. The results suggest that MRI can provide additional information in this group of patients. It can confirm bony union in a high proportion of patients deemed clinically non-united. Its use in this context will allow a more rapid mobilisation and return to normal function. The significance of persistent MR signal abnormalities in patients who have clinical and radiographic signs of healing merits further study.

Measurement of the anteroposterior translation of the humeral head using MRI.

Anteroposterior translation of the humeral head within the glenohumeral joint was investigated using MRI. Ten normal shoulders, 11 recurrent anterior dislocations, 10 stabilised shoulders after the Putti-Platt operation and one shoulder with multidirectional instability, were scanned. The arm was positioned in internal and external rotation and in an overhead position. Gradient echo volume acquisition scans were carried out, and 22 were suitable for evaluation. Consistent results were obtained in the normal shoulders. The unstable and unstable shoulders showed higher variance, but there was no significant anterior translation in external rotation in any group. The range of external rotation was significantly reduced in the unstable and stabilised shoulders. A trend towards posterior translation was found in internal rotation with a mean of 1 (+/- 0.44) in normal, 0.89 (+/- 1.67) in unstable and 1.6 (+/- 1.4) in stabilised shoulders.

MRI of Hoffa's fat pad.

The infrapatellar fat pad of Hoffa is commonly injured but rarely discussed in the radiological literature. Abnormalities within it most commonly are the consequences of trauma and degeneration, but inflammatory and neoplastic diseases of the synovium can be confined to the fat pad. The commonest traumatic lesions follow arthroscopy, but intrinsic signal abnormalities can also be due to posterior and superior impingements syndromes and following patellar dislocation. Infrapatellar plica syndrome may also be traumatic in aetiology. The precise aetiology of ganglion cysts is not understood; the principal differential diagnosis is a meniscal or cruciate cyst. Hoffa's fat pad contains residual synovial tissue, meaning that primary neoplastic conditions of synovium may originate and be confined to the fat pad. Inflammatory changes along the posterior border of the pad may also be used to help differentiate effusion from acute synovitis on unenhanced MR examinations.

Limited magnetic resonance imaging in low back pain instead of plain radiographs: experience with first 1000 cases.

AIM: We report our experience with the first 1000 patients with non-traumatic low back pain (LBP) without radiculopathy undergoing limited sequence magnetic resonance imaging (MRI) instead of plain radiography. METHODS: Between January 1996 and December 1998, 1042 patients with low back pain unresponsive to conservative treatment were examined using a limited MR protocol comprising sagittal T1-weighted and STIR imaging. Plain radiographs were not performed. RESULTS: Malignancy, infection, vertebral fracture, spondylitis, pars defects and cord tumours were detected in 20%. Of the 82 osteoporotic vertebral fractures detected, 51 (62%) were recent and 31 had normal marrow signal indicating that they were old. Eighty pars defects were identified, 45(56%) had spondylolisthesis, 29(37%) were undisplaced and 6 (7%) had pars oedema only. Neoplastic disease was found in 17(8%) of which none was suspected before imaging. Benign neoplastic diseases such as vertebral AVM/haemangiomata were excluded. Twenty-one patients had a variety of disorders including ankylosing spondylitis (7), large vessel aneurysm (3), discitis (2), ovarian cyst (2), sequestered disc (2), sacral insufficiency fracture (2) and one patient each with burst fracture, retroperitoneal haematoma and a previously unsuspected horseshoe kidney. CONCLUSION: The majority of patients with LBP are best assessed clinically and imaging is usually not required. In patients with worrying symptoms, MRI with a limited protocol detects a greater number of abnormalities than previously reported studies using plain radiographs and has replaced plain radiography in our hospital. We report our experience with the first 1000 patients and highlight issues such as protocols, detection rates and communication issues.

Assessment of patellar maltracking using combined static and dynamic MRI.

Between January 1995 and Jul 1997, 474 patients with anterior knee pain resistant to conservative treatment were referred for MR of the knee. The MR examination consisted of routine sequences with an additional patellofemoral dynamic examination using a technique that has been developed at this institution. The dynamic study examines both knees simultaneously, with the patient supine and the quadriceps loaded. No gating or restraint apparatus is needed. Patellar subluxation or tilt was present in 188(40%) of cases, bilateral in 104 and unilateral in 84 cases (right 39, left 45). It was classified as mild in 51%, moderate in 39% and severe in 10%. Subluxation was more prevalent in females than males (42% vs. 37%) and this was most obvious in the severe group where 68% were female. In 90 knees selected at random, four measurements of patellofemoral morphology were obtained using reconstructed images from a volume gradient echo sequence. These measurements were correlated with the degree of subluxation or tilt. A tibial tubercle distance greater than 20 mm, a femoral sulcus angle greater than 150 degrees, sulcus depth less than 4 mm were specific for subluxation but no measurement proved to be sufficiently sensitive to preclude a tracking study. MRI can be used to define more precisely the anatomy of the extensor mechanism and its relationship to the femur and tibia, in both a static and dynamic setting. In this way, patients with anterior knee pain can be classified more accurately and the outcomes of treatment more reliably assessed.