[Irritation of the iliopsoas tendon after total hip arthroplasty]

Chronic irritation of the iliopsoas tendon is a rare cause of persistent pain after total joint replacement of the hip. In the majority of cases, pain results from a mechanical conflict between the iliopsoas tendon and the anterior edge of the acetabular cup after total hip arthroplasty. Pain can be reproduced by active flexion of the hip and by active raising of the straightened leg. In addition, painful leg raising against resistance and passive hyperextension are suggestive of an irritation of the iliopsoas tendon. Symptoms evolve from a mechanical irritation of the iliopsoas tendon and an oversized or retroverted acetabular cup, screws penetrating into the inner aspect of the ilium, or from bone cement protruding beyond the anterior acetabular rim. The diagnosis may be assumed on conventional radiographs and confirmed by CT scans. Fifteen patients with psoas irritation after total hip replacement are reported on. Eleven patients were treated surgically. The acetabular cup was revised and reoriented with more anteversion in six patients, isolated screws penetrating into the tendon were cut and leveled in three patients, and prominent bone cement in conflict with the tendon was resected once. A partial release of the iliopsoas tendon only was performed in another patient. Follow-up examination (range: 11-89 months) revealed that nine patients were free of pain and two patient had mild residual complaints. Psoas irritation in combination with total hip replacement can be prevented by a correct surgical technique, especially with proper selection of the cup size and insertion of the acetabular cup avoiding a rim position exceeding the level of the anterior acetabular rim.

Septic mucormycosis in acute t-cell leucemia – pathogen detection in skin lesions

We report on a 43-year old patient with an acute T-Cell Leucemia, currently in Aplasia after Chemotherapy, showing five targetoid bluish skin lesions. Due to a three weeks history of septic symptoms he was under treatment with antibiotics and antifungals. Multiple septic foci were localized (N. caudatus, liver, kidneys, lung, spine and right psoas). Microbiology analyses of various blood cultures and of the aspirate of the psoas abscess showed initially negative results. Clinically the skin lesions were suspected to be of septic or thrombogenic origin. A 5 mm punch biopsy was performed and separated for microbiological diagnostic and conventional histology. Surprisingly large fungal agents in mostly intravascular distribution were seen histologically and identified as Lichtheimia corymbifera (syn. Absidia corymbifera) by PCR. Cultures remained negative. The patient died on the following day. Lichtheimia corymbifera is a fungus belonging to the family of mucormycosis. Aspergillosis and mucormycosis are the most common mold infections in patients with hematological malignancies, clinically often indistinguishable. However, the true incidence of mucormycosis is not known and probably underestimated because of difficulties in diagnosis. Mucormycosis typically causes acute, aggressive, and frequently angioinvasive infections presenting with solitary local skin necrosis. The fact that the pathogenic fungus was isolated from a very discrete skin lesion but was not detected in blood cultures, and only later in the PCR of the aspirate of the psoas abscess, makes this case exceptional.