Design, Development and Validation of a Knee Brace to Standardize the US Imaging Evaluation of Knee Osteoarthritis.

OBJECTIVE: A repeatable and reliable follow-up of knee injuries would be desirable to prevent delayed diagnosis and to monitor the efficacy of the applied treatment over time. Ultrasound (US) techniques are an attractive option to this purpose, since they are safe, low-cost and non-invasive. However, its use in the clinical practice is limited by the high dependency on the operator's experience. Hence, the objective of this study is to provide a standardization of the US image acquisition process for knee osteoarthritis (OA) allowing an extended clinical use of US technologies in this domain. METHODS: Clinical specifications were provided by expert musculoskeletal radiologists thus identifying the subject poses and the US probe positions needed to evaluate the cartilage structure, signs of synovitis and joint effusion. Such considerations were used to derive the technical requirements needed for the development of a wearable brace equipped with specific openings to guide the correct placement of the probe. The feasibility of the developed wearable brace was tested on three healthy volunteers, which were asked to acquire informative US images, similar to the reference images performed by the musculoskeletal radiologist. RESULTS: Thanks to the knee brace, the untrained subjects were able to self-acquire informative B-mode images comparable to the corresponding images acquired by an expert clinician. DISCUSSION/CONCLUSION: The use of a knee brace intended for knee OA US diagnosis demonstrated the possibility to standardize the acquisition protocol and make its application achievable also for untrained subjects, representing a key step toward tele-ultrasonography.

Does Osteoarthritis of the Ipsilateral Hip Develop After Knee Rotationplasty? A Radiologic Study on Patients with Long-term Survival Undergoing Surgery for Bone Tumors.

BACKGROUND: During routine check-ups of long-term surviving knee rotationplasty patients referred to our institute, we noted that the operated limb radiograph showed signs of hip osteoarthritis in some patients, and that one patient reported hip pain. We wondered whether radiographic changes and symptoms are common in patients undergoing rotationplasty due to mechanical or overloading problems during gait. Based on these considerations, we wished to determine how frequently arthrosis or arthritis would arise in the ipsilateral hip to a knee rotationplasty at long-term follow-up. To our knowledge, this issue has not been explored. Clinicians and patients should be aware of any problems that may affect the hip over time that could result in treatment. QUESTIONS/PURPOSES: At a minimum of 10 years after rotationplasty, in a single-center series, we therefore asked: (1) What proportion of patients reported hip pain at rest and with activity? (2) What proportion have radiographically visible arthritic changes in the ipsilateral or contralateral hip? (3) What proportion of patients have changes in the hip morphology (femoral rotation, cervicodiaphyseal angle, acetabular angle, osteopenia)? METHODS: Between 1986 to 2009, 42 patients underwent rotationplasty in our institute. They represent the 16.5% of a series of 254 children (age 3 to 14 years) affected by high-grade bone sarcomas located in the distal half of the femur. Three more patients were adolescents older than 15 years and were treated with rotationplasty because of the tumor volume and extracompartmental involvement. Of these 45 patients, 14 died of disease at a mean of 37 months; 31 patients were survivors at the time the study was done. Three of these long-term survivors were known to be alive but did not come for a clinic visit in the last 5 years. The remaining 28 patients were invited to participate in a research study on the long-term assessment of rotationplasty, and all agreed to participate. Unfortunately, 10 patients living far from our Institute could not come in the 2 days established for the assessment due to family or work constraints. AP plain radiographs of the pelvis were taken in 17 patients with long-term survival after knee rotationplasty. Patients were positioned in a standard weightbearing position, wearing their own prosthesis. Hip osteoarthritis was assessed using the Croft grading system. The presence of hip pain was assessed with the self-reported Numeric Rating Scale (NRS), with scores ranging from 0 to 10, at rest and during daily life activities. Femoral rotation, osteopenia, the cervicodiaphyseal and the acetabular angles were measured on radiographs. The median (range) age at follow-up was 32 years (22 to 45), the median age at the time of the intervention was 9 years (6 to 17), and the median follow-up duration after surgery was 25 years (11 to 30). RESULTS: One of the 17 patients complained of mild pain (NRS score of 2) in the ipsilateral hip during walking. No other patient claimed to have hip pain at rest or during walking or other daily life activities. Eleven of 17 patients had signs of OA according to the Croft grading system: one had Grade 1 OA, seven had Grade 2, and three had Grade 3. Six patients did not show any sign of OA in the ipsilateral hip. Two patients had Grade 1 OA and one had Grade 2 OA of the contralateral hip. Sixteen patients had femoral external rotation. An increased valgus cervicodiaphyseal angle and acetabular angle were present in 10 and 9 patients, respectively. Osteopenia at the ipsilateral hip when compared with the contralateral, was present in all patients but one, with varying degrees of severity. CONCLUSIONS: In this small series, signs of osteoarthritis of the hip ipsilateral to the rotationplasty were present in a high proportion of patients at a minimum follow-up interval of 10 years after surgery, although only one participant reported hip pain. The finding of arthrosis in the hip above a rotationplasty is potentially important because it may be related to gait abnormalities that may modify the hip's morphology over time. It is encouraging that symptomatic hip pain was uncommon in our patients, but this could become more of a clinical problem with longer follow-up and result in therapeutic intervention. Patients (or the parents of patients) undergoing this procedure should be informed that they might develop hip arthritis during young adulthood. LEVEL OF EVIDENCE: Level IV, therapeutic study.

Association between markers of bone loss and urinary lithogenic risk factors in osteopenic postmenopausal women.

In this study, we explored if urinary lithogenic risk parameters could have some application for monitoring bone health status. We recruited 20 women with postmenopausal osteopenia and a negative medical history for nephrolithiasis. Markers of lithogenic risk were evaluated on 24-h urine and fastingmorning urine. Serum levels of bone turnover markers (BTM) were measured in fasting-blood samples. We found that cross-linked telopeptide of type I collagen (CTX) was significantly correlated with 24-h calcium excretion. N-terminal propeptide of type I procollagen (PINP) correlated with 24-h excretion of potassium, calcium and citrate. CTX had considerably increased in patients with pH less than 5.5. Low citrate levels (less than 3.3 mmol/24 h) were associated with lower levels of CTX and PINP. Our findings suggest that a low-grade acidosis and some lithogenic risk factors are detectable in a proportion of patients with postmenopausal osteopenia. Further studies are necessary to confirm that this evaluation could be clinically relevant.

Contrast enhanced MRI and ¹8F-FDG PET-CT in the assessment of multiple myeloma: a comparison of results in different phases of the disease.

OBJECTIVES: The aim of our study was to compare the accuracy of contrast enhanced MRI and FDG PET-CT in the staging, treatment evaluation and follow-up of multiple myeloma. METHODS: We retrospectively reviewed 210 PET-CT and 210 MRI studies of patients affected by multiple myeloma. MRI was always performed within 15 days of PET-CT. All the images have been evaluated by two expert oncologic radiologists. RESULTS: Patient population included 81 females and 110 males (age 61.9 ± 9.9 years-old). Sixty-two patients have been evaluated at diagnosis, 58 at the end of therapies and 90 during follow-up. In 12/62 patients (19.4%) at diagnosis, differences between MRI and PET-CT findings determined changes in the staging: PET-CT was responsible for 11 down-staging (17.7%) and MRI only for one (1.6%). In 27/40 patients (67.5%) with good or complete clinical response to therapies the normalization of findings was faster for PET-CT than MRI. Ten out of 90 patients (10/90 - 11.1%) in follow-up protocol presented clinical recurrence of the disease: MRI detected active lesions in 8 of them (80.0%) and PET-CT in 5 patients (50.0%, all detected by MRI too). CONCLUSIONS: MRI achieved better results than PET-CT in the staging and in patients with multiple myeloma recurrence. PET-CT, showed prompt change of imaging findings, faster than MRI, in patients with positive response to therapy.