Comparison of extramedullary versus intramedullary referencing for tibial component alignment in total ankle arthroplasty.

BACKGROUND: The majority of total ankle arthroplasty (TAA) systems use extramedullary alignment guides for tibial component placement. However, at least 1 system offers intramedullary referencing. In total knee arthroplasty, studies suggest that tibial component placement is more accurate with intramedullary referencing. The purpose of this study was to compare the accuracy of extramedullary referencing with intramedullary referencing for tibial component placement in total ankle arthroplasty. METHODS: The coronal and sagittal tibial component alignment was evaluated on the postoperative weight-bearing anteroposterior (AP) and lateral radiographs of 236 consecutive fixed-bearing TAAs. Radiographs were measured blindly by 2 investigators. The postoperative alignment of the prosthesis was compared with the surgeon's intended alignment in both planes. The accuracy of tibial component alignment was compared between the extramedullary and intramedullary referencing techniques using unpaired t tests. Interrater and intrarater reliabilities were assessed with intraclass correlation coefficients (ICCs). RESULTS: Eighty-three tibial components placed with an extramedullary referencing technique were compared with 153 implants placed with an intramedullary referencing technique. The accuracy of the extramedullary referencing was within a mean of 1.5 ± 1.4 degrees and 4.1 ± 2.9 degrees in the coronal and sagittal planes, respectively. The accuracy of intramedullary referencing was within a mean of 1.4 ± 1.1 degrees and 2.5 ± 1.8 degrees in the coronal and sagittal planes, respectively. There was a significant difference (P < .001) between the 2 techniques with respect to the sagittal plane alignment. Interrater ICCs for coronal and sagittal alignment were high (0.81 and 0.94, respectively). Intrarater ICCs for coronal and sagittal alignment were high for both investigators. CONCLUSIONS: Initial sagittal plane tibial component alignment was notably more accurate when intramedullary referencing was used. Further studies are needed to determine the effect of this difference on clinical outcomes and long-term survivability of the implants. LEVEL OF EVIDENCE: Level III, retrospective comparative study

Rapid, progressive neuropathic arthropathy of the hip in a patient co-infected with human immunodeficiency virus, hepatitis C virus and tertiary syphilis: case report

BACKGROUND: Syphilis is a chronic infection that is classified into three stages. In its tertiary stage, syphilis spreads to the brain, heart and other organs; the lesions may involve the skin, mucous membranes and bones. Neuropathic arthropathy associated with tertiary syphilis has rarely been described in Europe and its association with HIV-HCV co-infection has not been reported so far.This article reports the case of a man with tertiary syphilis presenting with rapidly evolving neuropathic arthropathy of the hip and extensive bone destruction. CASE PRESENTATION: On initial presentation, the patient complained of progressively worsening left-sided coxalgia without localized or generalized inflammation. The patient reported to have no history of previous infections, trauma or cancer. Plain x-ray films of the left coxofemoral joint showed marked degeneration with necrosis of the proximal epiphysis of femur and morphological alterations of the acetabulum without protrusion. Primary coxarthrosis was diagnosed and hip arthroplasty was offered, but the patient declined treatment. Three months later, the patient presented a marked deterioration of his general condition. He disclosed that he was seropositive for HCV and HIV, as confirmed by serology. Syphilis serology testing was also positive. A Girdlestone's procedure was performed and samples were collected for routine cultures for bacteria and acid fast bacilli, all resulting negative.Although histological findings were inconclusive, confirmed positive serology for syphilis associated with progressive arthropathy was strongly suggestive of tertiary syphilis, probably exacerbated by HIV-HCV co-infection. The patient partially recovered the ability to walk. CONCLUSIONS: Due to the resurgence of syphilis, this disease should be considered as a possible cause of neuropathic arthropathy when other infectious causes have been ruled out, particularly in patients with HIV and/or HCV co-infection