No abstract

No abstract

Background Unicompartmental knee arthroplasty (UKA) is a recognized procedure for treatment of medial compartment osteoarthritis. UKA using minimally invasive surgery (MIS) has the theoretical advantage of less bone resection and quicker rehabilitation. Whether the function of patients with UKA compares with that of patients with conventional TKA is unclear. Questions/purposes We determined (1) the length of stay and complications associated with a short-stay MIS protocol; (2) whether MIS techniques allow for accurate positioning of the implant and alignment of the limb; (3) the change in functional scores; (4) the revision rate, reasons for revision, and survival of this implant. Patients and Methods We prospectively followed 100 patients who had 114 UKAs. All completed an International Knee Society (IKS) score preoperatively, at 1 year, and at last followup. We determined survivorship. Minimum followup was 5.2 years (mean, 7.4 years; range, 5.2-9 years). Results Mean length of stay was 1.2 days, with 41% discharged the same day. The perioperative complication rate was 6%. The mean IKS score improved from 77 to 93 and was 86 at last followup. The mean hip-knee-ankle axis changed from 6°varus to 1.7°varus. Twenty-two patients underwent a revision procedure at a mean 6.2 years after the index procedure. Survivorship of the prosthesis was 78% at 9 years. Conclusions The short-stay protocol was not associated with a high perioperative complication rate. This technique is associated with improvement in function and restoration of limb alignment, allowing accurate positioning of the implant. Compared with other reports of survival of UKA, this implant had a lower survivorship and increased revision rate.

A five-day-old boy was referred with a soft-tissue mass in his right upper arm. Plain radiographs and ultrasound demonstrated a lesion extending from the axilla to the elbow on the posterolateral aspect of the humerus. Open biopsy confirmed the diagnosis of congenital haemangiopericytoma. After MRI and selective angiography, excision biopsy was carried out, but no adjuvant therapy was administered. At further examination, four years and ten months later, he was noted to have three small nodules at the site of the original tumour. Excision biopsy confirmed this to be a local recurrence, although the lesion was less cellular with no appreciable mitotic activity. Congenital haemangiopericytoma is a rare cause of a soft-tissue mass in children. Most tumours are benign, and recurrence is uncommon. The treatment is controversial, but most centres recommend the use of adjuvant chemotherapy, combined with complete excision. We recommend treatment with doxorubicin. Orthopaedic surgeons should be familiar with this tumour since 30% to 50% of cases occur in the limbs.