Synovial cyst: an uncommon cause of back pain

Synovial cyst is an uncommon cause of back pain and radiculopathy. This case report describes the magnetic resonance imaging findings of two lumbar synovial cysts with special emphasis on the differential diagnoses of other extradural cystic lesions.     

Intra-articular fibrous band of the ankle: an uncommon cause of post-traumatic ankle pain

A case of an intra-articular fibrous band of the ankle is presented with emphasis on the MR imaging appearances. This entity is an important but uncommon cause of post-traumatic ankle pain and is well recognized within the arthroscopy literature, but there is little if any documentation of this condition in the imaging literature.     

A rare cause of chest pain: Cardiac synovial sarcoma

A 30-year-old male presented to the emergency department complaining of chest pain. Workup revealed a large cardiac mass causing compression of the cardiac chambers as the cause of his chest discomfort. This mass was subsequently diagnosed as a cardiac synovial sarcoma. Cardiac synovial sarcomas are very rare, primary malignant tumors of the heart, accounting for less than one percent of all cardiac tumors (Lv et al.,2010, Talukder et al., 2010). While only a few cases have been documented in the literature, this particular case demonstrates the importance of the continued work up for etiology of chest pain once more common etiologies like coronary heart disease (CHD) have been excluded, independent of patient age or comorbidities.     

Scrotal leiomyoma: An uncommon cause of chronic scrotal swelling

Leiomyoma is a benign tumor that arises from smooth muscle. It may be encountered at any part of the body especially the uterus. However, scrotal localization is very uncommon, hence it often requires radiologic and pathology correlation to establish an accurate diagnosis and make optimal decisions for subsequent treatment. We present a case of an 82-years-old male, presenting with a left scrotal mass. Ultrasound and MRI demonstrated a left paratesticular mass. Surgery was then indicated and pathology results were consistent with a scrotal leiomyoma.     

The quadriceps tendon cyst: an uncommon cause of chronic anterior knee pain

The causes of knee pain are manifold. One of the uncommon causes of chronic anterior knee pain are cysts and ganglia. Magnetic resonance imaging not only reveals the intra-articular pathology but also accurately depicts such cystic structures about the knee. As part of this case report, a cyst of the lateral border of the quadriceps tendon is presented as a cause of such discomfort. Although cystic lesions around the knee are a common clinical problem, the described location is rare. After surgical revision of the lateral border of the quadriceps tendon and excision of the cyst, the patient was found to be asymptomatic.     

An uncommon cause of acquired osteosclerosis in adults: hepatitis C-associated osteosclerosis

Hepatitis C-associated osteosclerosis (HCAO) is a rare sclerosing bone condition characterized by debilitating, predominantly lower extremity bone pain, accelerated bone turnover, and a generalized increase in histologically normal trabecular and cortical bone tissue. Herein we report the clinical presentation and imaging results of the 19th case of HCAO. Clinicians, particularly those caring for a population at risk for HCV infection, should be aware of this uncommon condition. The etio-pathogenesis of HCAO remains obscure but may bear important lessons in bone biology that could lead to new treatment options for osteoporosis.     

Desmoid tumor of the mesentery. An uncommon cause of ureteral obstruction]

Desmoid tumors are rare lesions with a local invasive potential and a risk of recurrence considered as benign due to the absence of metastases. They are included in fibromatoses and may be associated with Gardner's syndrome. The authors report an unusual case, in a 26 year old man, of a desmoid tumor invading ileon, right colon, appendix and the right ureter and responsible of a ureteral obstruction. Etiologic factors (traumatic, hormonal, auto-immune...) are discussed. The treatment of choice to lower the risk of recurrence is the complete surgical removal of the tumor.     

Inverted papilloma: An uncommon benign cause of a ureteral filling defect

A case of inverted papilloma of the ureter in a 62-year-old man is presented along with a literature review of 14 cases. This rare benign tumor should enter the differential diagnosis of a ureteral filling defect especially when it has a smooth configuration. Preoperative consideration of this diagnosis may lead to intraoperative confirmation of pathology and conservative resection.     

Localised pigmented villonodular synovitis: an uncommon cause of knee pain mimicking a meniscal tear

A previously well 30 year old man presented with a short history of intra-articular mechanical locking, swelling, and anteromedial joint line pain. There was localised tenderness, and McMurray's test was positive. Arthroscopy revealed a 3.6 x 2.6 x 1.5 cm firm pedicular localised pigmented villonodular synovitis originating from the insertion of the anterior horn of the medial meniscus. Owing to its size and consistency, mini-arthrotomy was required. This allowed a return to sporting activities. Localised pigmented villonodular synovitis can mimic symptoms of a meniscal tear.     

An uncommon cause of cemented unicompartmental knee arthroplasty failure: fracture of metallic components

Purpose

Despite good overall clinical results, unicompartmental knee replacements (UKR) are not without their problems and failures have been reported. The most common causes of UKR failure are component loosening, poor patient selection, poor surgical technique, polyethylene wear and progression of arthritis in other compartments. The purpose of this study is to present a series of atraumatic fractures of metallic components in a UKR treated in a single orthopaedic centre.

Method

Since 1999, 121 failed unicompartmental knee arthroplasties have been referred to our centre. In six of these, atraumatic breakage of a metal component in the cemented UKR was seen and included in this study. Pre-operative alignment, BMI and implant longevity were documented. The femoral implant failed in 4 patients and the tibial implant in a further 2.

Results

All the femoral implant fractures occurred within 3 years of UKR surgery (mean: 22.2 months, SD: 10.6 months). Tibial implant breakage occurred at a mean of 8.5 years (SD: 2.4 months) following UKR. All patients were treated with conversion to a navigated total knee replacement. A primary total knee arthroplasty was used in all cases with one patient requiring a tibial component incorporating a wedge and stem following breakage of the original UKR tibial implant.

Conclusion

Fracture of the metallic components is a potential cause of failure of unicompartmental knee arthroplasty. In our experience, the incidence of this complication was 4.9 % of all UKR failures. Patients with a BMI greater than 30 and a progressive deterioration in limb alignment were at greater risk.

Level of evidence

IV.