ISCHIOFEMORAL IMPINGEMENT DUE TO A SOLITARY EXOSTOSIS.

Ischiofemoral impingement is a rare cause of hip pain related to narrowing of the space between the ischial tuberosity and the lesser trochanter. It is usually seen in middle-aged women. We report a rare case of a young male patient presenting with ischiofemoral impingement due to a solitary exostosis at the lesser trochanter. Imaging, especially Magnetic Resonance Imaging (MRI), is an excellent tool to confirm the diagnosis by demonstrating narrowing of the ischiofemoral space and soft tissue edema in the muscle belly of the quadratus femoris muscle.

Postsurgical compartment syndrome of the forearm diagnosed in a child receiving a continuous infra-clavicular peripheral nerve block.

Opinions diverge as to whether or not regional anaesthesia delays the diagnosis of evolving acute compartment syndrome. Withholding regional anaesthesia from patients with painful orthopaedic injuries may be ethically unacceptable, however. In this report, we describe a case of acute compartment syndrome in a 4-year old child who underwent resection of a forearm osteochondroma. Analgesia was satisfactory during the first post-operative night, but the child later complained of pain despite an effective infra-clavicular block. Motor function and sensibility were disturbed and the fingers were swollen. The forearm cast was removed as it was suspected to be causing external compression. Pain disappeared while motor function and sensation recovered. The child was discharged without any complications. Despite an effective peripheral nerve block and the young age of the patient, the diagnosis of acute compartment syndrome could be made thanks to a well-defined post-operative analgesia protocol, a high level of suspicion and careful clinical assessment when break-through pain occurred.

TruFit Plug for Repair of Osteochondral Defects-Where Is the Evidence? Systematic Review of Literature.

OBJECTIVE: Treatment of osteochondral defects remains a challenge in orthopedic surgery. The TruFit plug has been investigated as a potential treatment method for osteochondral defects. This is a biphasic scaffold designed to stimulate cartilage and subchondral bone formation. The aim of this study is to investigate clinical, radiological, and histological efficacy of the TruFit plug in restoring osteochondral defects in the joint. DESIGN: We performed a systematic search in five databases for clinical trials in which patients were treated with a TruFit plug for osteochondral defects. Studies had to report clinical, radiological, or histological outcome data. Quality of the included studies was assessed. RESULTS: Five studies describe clinical results, all indicating improvement at follow-up of 12 months compared to preoperative status. However, two studies reporting longer follow-up show deterioration of early improvement. Radiological evaluation indicates favorable MRI findings regarding filling of the defect and incorporation with adjacent cartilage at 24 months follow-up, but conflicting evidence exists on the properties of the newly formed overlying cartilage surface. None of the included studies showed evidence for bone ingrowth. The few histological data available confirmed these results. CONCLUSION: There are no data available that support superiority or equality of TruFit compared to conservative treatment or mosaicplasty/microfracture. Further investigation is needed to improve synthetic biphasic implants as therapy for osteochondral lesions. Randomized controlled clinical trials comparing TruFit plugs with an established treatment method are needed before further clinical use can be supported.

Does infrapatellar fat pad resection in total knee arthroplasty impair clinical outcome? A systematic review.

INTRODUCTION: The infrapatellar fat pad (IPFP) is often removed during total knee arthroplasty (TKA). No evidence based guidelines on changes in clinical outcome have yet been described. The aim of this review is to investigate whether regular removal of the IPFP during TKA should be performed. MATERIAL AND METHODS: Seven databases were systematically searched. Clinical studies, in which TKA with IPFP resection was compared with IPFP preservation, were included. Risk of bias was assessed using the Cochrane collaboration tool. Studies reporting anterior knee pain, patellar tendon length, range of motion, patellar vascularisation or functional outcome were included. RESULTS: The indication for TKA varied in the different studies: osteoarthritis (OA), rheumatic arthritis (RA) and multiple indications (OA, RA and osteonecrosis). After IPFP resection: 1. For OA, no differences in function, range of motion, and anterior knee pain were found. 2. In the RA study, there was a trend towards more discomfort and a decrease in function. 3. In OA and RA patients a decrease in patellar tendon length was observed. 4. One study reported no decrease in patellar vascularisation. DISCUSSION: Limitations of this review are the high risk of bias scores of the included studies, the varying outcome measures, follow up, number and type of participants. Randomised clinical trials are required to support or refute the results, contributing to a possible future evidence based guideline on IPFP resection during TKA.

Peroxisome proliferator activated receptor alpha activation decreases inflammatory and destructive responses in osteoarthritic cartilage.

OBJECTIVE: Peroxisome proliferator activated receptor α (PPARα) agonists are used in clinical practice as lipid-lowering drugs and are also known to exert anti-inflammatory effects on various tissues. We hypothesized that PPARα activation leads to anti-inflammatory and anti-destructive effects in human OA cartilage. METHODS: Cartilage explants obtained from six OA patients were cultured for 48 h with 10 ng/ml interleukin (IL)1ß as a pro-inflammatory stimulus. 100 µM Wy-14643, a potent and selective PPARα agonist, was added to the cultures and gene expression of matrix metalloproteinase (MMP)1, MMP3, MMP13, collagen type II (COL2A1), aggrecan and PPARα in cartilage explants and the release of glycosaminoglycans (GAGs), nitric oxide (NO) and prostaglandin E(2) (PGE(2)) in the culture media were analyzed and compared to the control without Wy-14643. RESULTS: Addition of Wy-14643 decreased mRNA expression of MMP1, MMP3 and MMP13 in cartilage explants that responded to IL1ß, whereas Wy-14643 did not affect gene expression of COL2A1 and aggrecan. Wy-14643 also decreased secretion of inflammatory marker NO in the culture medium of cartilage explants responding to IL1ß. Wy-14643 inhibited the release of GAGs by cartilage explants in culture media. CONCLUSION: PPARα agonist Wy-14643 inhibited the inflammatory and destructive responses in human OA cartilage explants and did not have an effect on COL2A1 or aggrecan mRNA expression. These effects of PPARα agonists on osteoarthritic cartilage warrant further investigation of these drugs as a potential therapeutic strategy for osteoarthritis (OA).

Fibula metastasis as the presenting feature of vaginal cancer.

BACKGROUND: Metastatic bone involvement in vaginal carcinoma has not been reported in the literature. CASE: A 74-year-old woman was referred for a painful fibula to the orthopedic surgeon. A work-up revealed an isolated metastatic bone lesion in the right fibula of a primary squamous carcinoma of the vagina. Rather surprisingly this lesion had been missed during all previously regular clinical gynecological examinations. Palliative therapy including bone resection and radiotherapy of the metastatic lesion were given. CONCLUSION: This case highlights: (1) the unique presentation of a vaginal cancer by pain in the lower leg secondary to a metastasis in the fibula; (2) that a speculum examination can mask a mid-vaginal lesion; (3) the importance of aggressive treatment of a solitary bone metastasis in order to provide effective palliation.

The infrapatellar fat pad should be considered as an active osteoarthritic joint tissue: a narrative review.

INTRODUCTION: Osteoarthritis (OA) of the knee joint is caused by genetic and hormonal factors and by inflammation, in combination with biomechanical alterations. It is characterized by loss of articular cartilage, synovial inflammation and subchondral bone sclerosis. Considerable evidence indicates that the menisci, ligaments, periarticular muscles and the joint capsule are also involved in the OA process. This paper will outline the theoretical framework for investigating the infrapatellar fat pad (IPFP) as an additional joint tissue involved in the development and progression of knee-OA. METHODS: A literature search was performed in Pubmed from 1948 until October 2009 with keywords InFrapatellar fat pad, Hoffa fat pad, intraarticular adipose tissue, knee, cartilage, bone, cytokine, adipokine, inflammation, growth factor, arthritis, and OA. RESULTS: The IPFP is situated intracapsularly and extrasynovially in the knee joint. Besides adipocytes, the IPFP from patients with knee-OA contains macrophages, lymphocytes and granulocytes, which are able to contribute to the disease process of knee-OA. Furthermore, the IPFP contains nociceptive nerve fibers that could in part be responsible for anterior pain in knee-OA. These nerve fibers secrete substance P, which is able to induce inflammatory responses and cause vasodilation, which may lead to IPFP edema and extravasation of the immune cells. The IPFP secretes cytokines, interleukins, growth factors and adipokines that influence cartilage by upregulating the production of matrix metalloproteinases (MMPs), stimulating the expression of pro-inflammatory cytokines and inhibiting the production of cartilage matrix proteins. They may also stimulate the production of pro-inflammatory mediators, growth factors and MMPs in synovium. CONCLUSION: These data are consistent with the hypothesis that the IPFP is an osteoarthritic joint tissue capable of modulating inflammatory and destructive responses in knee-OA.

Medical and surgical management of paraneoplastic pyoderma gangrenosum--a case report and review of the literature.

We present a case of a 44-year-old male with pyoderma gangrenosum (PG) presenting simultaneously with diagnosis of acute leukemia. His skin disease was stabilized with corticosteroids and most lesions cleared after chemotherapy-induced remission of the malignancy, but the largest lesion remained necrotic. Surgical treatment of the large necrotic ulcer included debridement followed by split-thickness skin graft while maintaining corticoid therapy. Unfortunately, relapse of the pyoderma gangrenosum with bullous lesions heralded relapse of the ultimately fatal malignancy. This case illustrates: (1) PG presenting simultaneously with a haematologic malignancy (2) Relapse with atypical bullous lesions with return of the malignancy and (3) The use of surgical modalities in managing patients with PG, a disease notorious for surgical complications.

Analysis of surgical errors in malpractice claims in Belgium.

The relative importance of the different factors that cause surgical error is unknown. Malpractice claim file analysis may help to identify leading causes of surgical errors and identify opportunities for prevention. We retrospectively reviewed 427 surgical malpractice claims from 3202 malpractice liability cases in which patients alleged error between 1996 and 2006. Surgeon-reviewer examined the litigation file and medical record to determine whether and injury attributable to surgical error had occurred and, if so, what factors contributed. Detailed descriptive information concerning etiology and outcome was recorded. The reviewer identified surgical errors that resulted in patient injury in the 427 studied claims. Sixty-three percent of these cases involved significant or major injury; 6% involved death. In most cases (48%), errors occurred in intra operative care; 15% in preoperative care; 37% in postoperative care. Nine percent of the cases had errors occurring during multiple phases of care; in 28%, more than one clinician played a contributory role. System factors contributed to error in 90% of cases. The leading system factors were inexperience/lack of technical competence (57%) and communication breakdown (42%). Cases with technical errors (57%) were more likely than those without technical errors (43%) to involve elective surgery (57% vs. 60%, Fisher's Exact Test < 0.001). There were no clear contributions to error from multiple personnel (26% vs. 31%, Fisher's Exact Test 0.28) and errors in multiple phases of care (73% vs. 68%, Fisher's Exact Test 0.28). In addition technical error cases were more likely than those without technical errors to have been caused by lack of clear lines (14% vs. 21%, Fisher's Exact Test 0.03), abnormal or different anatomy (6% vs. 2%, Fisher's Exact Test 0.04), interruption or distraction (14% vs. 4%, Fisher's Exact Test < 0.001). On the other hand, they were less likely to have been caused by judgment errors (47% vs. 59%, Fisher's Exact Test < 0.001). There were significant more problems caused by the numbers of personnel involved in university hospitals than in non-university hospitals. On the other hand, they were less likely to have been caused by failure of vigilance/memory (16% vs. 58% Fisher's Exact Test < 0.001), breakdown (19% vs. 50%, Fisher's Exact Test < 0.001), lack of supervision (2% vs. 34%, Fisher's Exact Test < 0.001) and lack of clear lines (1% vs. 22%, Fisher's Exact Test < 0.001) in university hospitals than in non-university hospitals. System factors play an important role in most surgical errors, including technical errors and some non technical errors. Malpractice claims analysis could encrypt the leading areas for intervening to reduce errors.

Imaging findings of a subcutaneous angioleiomyoma.

Angioleiomyoma is a benign smooth muscle tumor arising from the vessel walls.The tumor can occur anywhere in the body, but is most often seen in the extremities, particularly in the lower leg. The most common presentation is a solitary subcutaneous nodular lesion, which is either painful or painless. We report a rare case of a slowly growing solid angioleiomyoma of the right lower leg in a 34-old-year old man. Although imaging characteristics on MR imaging and ultrasound are nonspecific, angioleiomyoma should be considered in the differential diagnosis when a mobile, slowly growing and well vascularised lesion is encountered in the extremities.

Superior sulcus tumor arising in an azygos lobe.

A non-small cell lung cancer presenting as a superior sulcus tumor in an azygos lobe has not yet been reported. We present such a case in a 69-year-old man undergoing complete resection after induction chemoradiotherapy and discuss the specific location of a superior sulcus tumor and the aberrant anatomy of an azygos lobe.

Nodular fasciitis: correlation of MRI findings and histopathology.

OBJECTIVE: To compare the histopathology of nodular fasciitis (NF) with the magnetic resonance imaging (MRI) findings in order to evaluate the basis of the MR signal characteristics. DESIGN AND PATIENTS: Ten patients with NF, nine females and 1 male, with an age ranging from 13 to 58 years (mean 26.8 years) were studied. MRI findings, available in all 10 patients, were compared with the histopathology in nine patients, and an area-to-area comparative study of the whole specimen section histopathology and MRI was performed in two patients. RESULTS: On the basis of an excisional biopsy or resection specimen, the nine lesions were classified into myxoid ( n=4), cellular ( n=3) and fibrous ( n=2) subtypes. Four myxoid lesions with a subcutaneous location showed a homogeneous SI comparable with muscle on T1-weighted images, high SI on T2-weighted images, and had homogeneous enhancement. One cellular lesion presented with homogeneous, slightly higher SI than muscle on T1-weighted images and inhomogeneous, high SI on T2-weighted images. Alcian blue stain of the whole specimen section revealed the lesion had two parts corresponding to different enhancement patterns on MRI. The blue-stained myxoid part showed markedly diffuse enhancement, while the non-stained cystic space had only peripheral enhancement. Two other cellular lesions had the same appearance on both T1- and T2-weighted images and showed inhomogeneous, diffuse enhancement. One fibrous subtype lesion presented with inhomogeneous, overall slightly higher SI than muscle on T1-weighted images, lower SI at the periphery and high SI in the center on STIR images and only peripheral enhancement. Microscopy and CD-31 staining of the lesion showed more extracellular matrix, with poor vascularity in the center and more collagenous matrix with higher vascularity at the periphery. CONCLUSION: Although similar findings were found in some lesions, the large histologic variability of NF hampers the definition of a prototype of NF on MRI. However, the MRI appearance of the myxoid subtype is rather characteristic. Histologic findings reflect the different SI characteristics and enhancement pattern on MRI.

Reliability of measuring volume by different methods for tumors of the musculoskeletal system.

In the present study different methods for determining the volume of a tumor were evaluated. For 12 models, the real volume, the volume according to measurement of the surface area on MRI, an ellipsoid and a cylindrical approximation of the volume, as well as the maximum diameter, were determined. There appeared to be a good correlation between all calculated volumes and the real volume. The error (mean: 17%) and the standard deviation (SD: 14%) on this error were smallest if the volume was determined by means of determination of the surface area. The ellipsoid approximation resulted in a smaller error (mean: 0%) but a higher standard deviation (SD: 27%). The cylindrical approximation resulted in unacceptable deviations (mean: 51%; SD: 40%). Volume was significantly related to the maximal diameter to the power of 2.3. Volume calculated according to this power resulted in an error of 18%. Standard deviation in this case however was unacceptable (SD: 89%). Volume calculation based upon the determination of the surface area has given the best and most reliable results. Ellipsoid approximation was less reliable, but faster and cheaper. Cylindrical approximation was unacceptable. Size, expressed as maximal diameter of the tumor, was also unacceptable as a parameter for volume.

Surgery for primary bone sarcomas of the pelvis.

Primary bone sarcomas of the pelvis represent the most challenging problem in limb-saving surgery. Chondrosarcoma is the most common type, followed by osteosarcoma and Ewing's sarcoma. The symptoms are often vague, so that the diagnosis is made late, when the tumor has already reached a large size. Nowadays hindquarter amputation is reserved for complex tumors involving the sacrum, the sciatic nerve, the iliac vessels or the bladder. Internal hemipelvectomy should be undertaken whenever possible; the reconstructive techniques are based on the three anatomic regions concerned: ilium, periacetabular area, and pubis. Complications occur in more than 50% of the patients. The 5-year survival rate is about 55%. Special scores, such as the MSTS/ISOLS and the TESS score, should be used to make the various studies comparable.

MR imaging of clear cell sarcoma (malignant melanoma of the soft parts): a multicenter correlative MRI-pathology study of 21 cases and literature review.

OBJECTIVE: To evaluate MR imaging and pathology findings in order to define the characteristic features of clear cell sarcoma of the soft tissues (malignant melanoma of the soft parts). DESIGN AND PATIENTS: MR examinations of 21 patients with histologically proven clear cell sarcoma of the musculoskeletal system were retrospectively reviewed and assessed for shape, homogeneity, delineation, signal intensities on T1- and T2-weighted images, contrast enhancement, relationship with adjacent fascia or tendon, secondary bone involvement, and intratumoral necrosis. In 19 cases the pathology findings were available for review and for a comparative MR-pathology study. RESULTS: On T1-weighted images, lesions were isointense (n=3), hypointense (n=7) or slightly hyperintense to muscle (n=11). Immunohistochemical examination was performed in 17 patients. All 17 specimens showed positivity for HMB-45 antibody. In nine of 11 lesions with slightly increased signal intensity on T1-weighted images, a correlative MR imaging-pathology study was possible. All nine were positive to HMB-45 antibody. CONCLUSIONS: Clear cell sarcoma of the musculoskeletal system often has a benign-looking appearance on MR images. In up to 52% of patients, this lesion with melanocytic differentiation has slightly increased signal intensity on T1-weighted images compared with muscle. As the presence of this relative higher signal intensity on T1-weighted images is rather specific for tumors displaying melanocytic differentiation, radiologists should familiarize themselves with this rare entity and include it in their differential diagnosis when confronted with a well-defined, homogeneous, strongly enhancing mass with slightly higher signal intensity compared with muscle on native T1-weighted images.

Magnetic resonance imaging of soft tissue tumors.

This article outlines the ability of MR imaging in staging, grading, tissue characterization, and posttherapeutic surveillance of soft tissue tumors. Well-known staging parameters, such as extent, relationship with adjacent structures, and detection of intralesional necrosis, are used in the MR protocol for locoregional staging. Bone scintigraphy and high-resolution CT scan of the lungs are best methods for ruling out metastatic spread. A variety of (solitary or combinations of) grading parameters are described in the radiological literature. The role of MR imaging is to afford recognition of these lesions that need further aggressive work-up, excluding all others. Despite controversial reports, the definite role of MR imaging in grading of soft tissue tumors seems to become established. As for grading, a lot of individual imaging characteristics used for tissue characterization have low sensitivity, but combinations of parameters (age, site, signal intensities) are more useful and often allow to predict a specific diagnosis or to narrow down the list of differential diagnoses. Local recurrences of soft tissue tumors are frequent and can be detected accurately by an easy-to-use MR algorithm.

Clinical relevance of acetabular erosion in young patients with a bipolar hip prosthesis.

In elderly patients bipolar hip prostheses are often used for intracapsular fractures of the femoral neck and are often complicated by pain after a few years; this pain is frequently related to acetabular erosion seen on xray. In this study 18 bipolar hip prostheses were used in the treatment of a proximal femoral sarcoma in a young patient population (mean age: 39.6 years). Their quality of life was evaluated by TESS and MSTS scores, after a mean follow-up of 81.8 months (range 8-171 months). A radiologic grading system was used to assess acetabular erosion on plain xrays. The patients did not report significant pain, they enjoyed a very good quality of life, and they did not show any obvious acetabular erosion. The use of a bipolar implant appears as a good alternative to total hip replacement in the treatment of relatively young patients who have to undergo proximal femoral tumor resection procedures and have a normal acetabulum.

Late peritoneal metastasis in a patient with osteosarcoma.

A 19-year-old man with a high-grade osteosarcoma of the femur, treated with neoadjuvant chemotherapy, surgery, and adjuvant chemotherapy suffered from lung metastases 15 months after diagnosis. They were resected. Thirteen months later, he had vague abdominal complaints which, after analysis, proved to be caused by peritoneal metastasis. A review of the literature, possible physiopathological mechanisms of increased occurrence of unusual metastases and the role of bone scintigraphy in the follow-up of patients with osteosarcoma are discussed.