Fatigue stress fractures of the pelvis: a rare cause of low back pain in female athletes.

Stress fracture of the pelvis represents one rare differential diagnosis among the manifold causes of low back pain in female athletes. We report a case of fatigue stress fracture of the pelvis in a 24-year-old female athlete as an unusual differential diagnosis of low back pain that should be taken into consideration. According to the literature the incidence of low back pain in athletes ranges from 1% to 30% and is influenced by sport type, gender, training intensity, training frequency and technique. In some cases, no specific pain generator is found, which makes diagnosis and treatment difficult. The frequency of the injury and the treatment options are discussed, based on published studies.

In-vitro MRI detectability of interbody test spacers made of carbon fibre-reinforced polymers, titanium and titanium-coated carbon fibre-reinforced polymers.

The purpose of this study was to investigate how different materials affect the magnetic resonance imaging (MRI) detectability of interbody test spacers (ITS). We evaluated the post-implantation MRI scans with T1 TSE sequences for three different ITS made of titanium, carbon fibre-reinforced polymers (CFRP) and titanium-coated CFRP, respectively. The main target variables were total artefact volume (TAV) and median artefact area (MAA). Additionally, implant volume (IV)/TAV and cross section (CS)/MAA ratio were determined. The t test and Newman-Keuls test for multiple comparisons were used for statistical analysis. TAV and MAA did not differ significantly between CFRP and titanium-coated CFRP, but were approximately twice as high for the titanium ITS (p < 0.001). MRI detectability was optimum for CFRP and titanium-coated CFRP, but was limited at the implant-bone interface of the titanium ITS. The material's susceptibility and the implant's dimensions affected MRI artefacting. Based on TAV, the volume of titanium surface coating in the ITS studied has no influence on susceptibility in MRI scans with T1 TSE sequences.

Arthrodesis of the knee after failed infected total knee arthroplasty.

Infection after total knee arthroplasty (TKA) can be a challenging and difficult problem to treat. In selected patients, knee arthrodesis is a well-recognized salvage procedure after infected TKA. The authors retrospectively reviewed their experience with this treatment option, presenting 20 patients (8 women, 12 men), performed between 1990 and 2002. The average age was 67 years (range: 47-81 years) and the mean number of previous surgical procedures was 6 (range: 4-11 procedures). There were multiple indications for knee arthrodesis, including extensive bone or soft tissue loss, poor bone stock, and recurring infections. One-stage fusion was done in 7 knees while, on the other 13, arthrodesis was performed as two-stage fusions. The average clinical follow-up was 4.5 years (range: 2-11 years). 18 of the 20 patients were interviewed and graded using the Visual Analogue Scale (VAS) for pain, the Short Form-36 Health Survey (SF-36), and the Knee injury and Osteoarthritis Outcome Score (KOOS) questionnaire that has knee-related quality of life items. According to the VAS, the mean intensity was 3.4 points. 6 (33%) of the patients had no difficulty with the knee and 9 (50%) of them had mild or moderate difficulty. The SF-36 scores were similar to those for normative data for patients after TKA, with only the social functioning, role emotional, and physical functioning scores being lower and the role physical and social functioning scores being higher. Three of 20 fusions failed, whereas two knees became non-infected non-unions. In one, the knee infection persisted and required above-knee amputation. The two-stage arthrodesis gave the most predictable rate of fusion. Persistent infection and extensive bone stock losses led to failure even under the best circumstances. In our opinion, arthrodesis of the knee is a satisfactory salvage procedure following a failed TKA, and can provide reliable expectation for a stable, painless extremity for high-functioning patients who are able to walk.

A study of effectiveness of knee arthroscopy after knee arthroplasty.

PURPOSE: The purpose of this study was to investigate the outcome of arthroscopy in painful knee arthroplasty without evidence of infection, fracture, wear, and component loosening or malposition that had been refractory to conservative treatment. In addition, a literature review of 498 cases (MEDLINE 1966 to 2002) was performed. TYPE OF STUDY: Case series. METHODS: From 1997 to 2000, 27 patients (20 women, 7 men) had undergone arthroscopies because of poor results following total knee arthroplasty. Before the operation, the patients had suffered symptoms for an average of 11 months (range, 3 to 41 months). The average onset of symptoms after knee arthroplasty was 26 months (range, 3 to 59 months). The average patient age was 70 years (range, 42 to 81 years) and the average follow-up was 34 months (range, 24 to 52 months). At the initial operation, 19 patients had received total condylar surface replacement and 8 had received hemireplacement. Patients were evaluated using the Knee Society rating system. A review of the literature was performed by initial identification of the articles from a MEDLINE database followed by the use of cross references. RESULTS: All of the patients were available for follow-up. Eighteen of the 27 procedures resulted in an improvement in the patient's knee score. The average Knee Society ratings increased from 71 points before arthroscopy to 85 at follow-up for the knee score. The average functional scores were 69 and 83 points, respectively. The Knee Society pain score improved from 32 to 41 points. Nine patients underwent a subsequent open revision after arthroscopic diagnosis or treatment. Operative diagnoses included arthrofibrosis, impinging hypertrophic synovitis, impinging posterior cruciate ligament stump, prosthesis loosening or wear, symptomatic pseudomeniscus, an infrapatellar spur, and meniscal rupture. There was 1 infection as a complication associated with the arthroscopic procedure. CONCLUSIONS: Arthroscopic treatment of painful knee arthroplasty provides reliable expectations for improvement in function, decrease in pain, and improvement in knee scores for most patients. LEVEL OF EVIDENCE: Level IV, Case Series.

Morbus Teutschländer - a massive soft-tissue calcification of the foot in a patient on long-term hemodialysis.

Morbus Teutschländer is a benign metabolic disorder involving soft-tissue masses near large joints and a rarely observed form of extraskeletal calcifications. For example, it is seen in patients with chronic renal failure, but in most cases it remains clinically silent. In a minority of patients, this soft-tissue calcification is responsible for complications. Various locations of calcium deposits have been characterized. Advanced age and increased calcium x phosphate product are some of the underlying reasons, but local factors are involved as well. Prevention should be preferred because the treatment is generally difficult. We describe the case of a morbus Teutschländer in a 58-year-old woman with chronic renal failure on hemodialysis presenting with a massive soft-tissue calcification of the foot with a compression of a cutaneous nerve secondary due to uremic tumoral calcinosis. The tumoral masses was successfully excised, and at the 1-year follow-up, the patient had no discomfort. Clinical and radiological features and treatment are discussed, and a review of soft-tissue calcifications is given.