Pinpoint accuracy: guided core biopsy diagnostic accuracy in musculoskeletal lesions.

BACKGROUND: Core biopsy is integral in the work-up of diagnosis for musculoskeletal lesions. Prior to referral through Christchurch hospital-a tertiary referral centre for sarcomas/musculoskeletal lesions, many patients undertake guided core biopsy in peripheral hospitals. We wished to assess the accuracy of these biopsies undertaken in the peripheral centres and compare to those done in the tertiary setting. METHODS: A retrospective analysis of image-guided core biopsies done in the South Island of New Zealand over a 5 year period was performed. An electronic database enquiry was made, and electronic notes were then screened for core biopsy results including subsequent biopsies done of the same lesion. Results from guided core biopsy were then recorded as diagnostic if the pathologist was able to reach or a definitive diagnosis, or guide management sufficiently. RESULTS: 223 patients with 229 biopsies were analysed. Overall accuracy of core biopsies were 83% across all centres. There were similar results between CT and ultrasound as well as soft tissue and bone lesions. Between the regions, the peripheral centres showed high accuracy compared with the tertiary centres. CONCLUSION: The regional centres demonstrated high diagnostic yield, and the current practice of providing core biopsy locally where possible prior to referral to a tertiary sarcoma, remains valid.

Tibial metaphyseal cones combined with short stems perform as well as long stems in revision total knee arthroplasty.

BACKGROUNDS: There is uncertainty around optimal tibial stem length in revision total knee arthroplasty (rTKA) utilizing a tibial trabecular metal (TM) cone. The purpose of this study was to compare: (1) functional outcomes, (2) radiographic outcomes and (3) implant survivorship in rTKA utilizing TM cones combined with either short stems (SS) or long stems (LS) at minimum 2 years follow-up. METHODS: In this retrospective, multi-centre study, patients undergoing rTKA utilizing a TM cone between 2008 and 2019 were included. Patients were divided into: SS group (no diaphyseal engagement), and LS group (diaphyseal engagement). All relevant clinical charts and post-operative radiographs were examined. Oxford Knee Score (OKS) and EuroQol-5D (EQ-5D-5L) data were collected at most recent follow-up. RESULTS: In total, 44 patients were included: 18 in the SS group and 26 in the LS group. The mean time of follow-up was 4.0 years. Failure free survival was 94.4% for the SS group and 92.3% for the LS group. All failures were for prosthetic joint infections managed with debridement, antibiotics, and implant retention. At most recent follow-up, 3 patients demonstrated radiographic signs of lucency (1 SS 2 LS, P = 1) and the mean OKS were 37 ± 4 and 36 ± 6 (P = 0.73) in the SS and LS groups, respectively. CONCLUSION: Tibial SS combined with TM cones performed as well as LS in rTKA at minimum 2 years follow-up. A tibial SS in combination with a TM cone is a reliable technique to achieve stable and durable fixation in rTKA.