Patient-reported outcomes after primary rotating hinge total knee arthroplasty: a multi-centre clinical cohort study.

PURPOSE: Rotating hinge prostheses for total knee arthroplasty (TKA) are mostly used in revision setting; however, evidence on the use of these constrained devices in primary setting is scarce and inconsistent. Therefore, we aimed to evaluate the functional outcomes after third-generation rotating hinge implants in primary TKA with a minimal follow-up of two years in a large dual-centre observational retrospective clinical trial. METHODS: The hospital databases of two centres were searched for primary rotating hinge arthroplasty from January 2007 to January 2015. A minimum follow-up of at least two years was assured. Patients meeting the inclusion criteria were asked to fill out two self-reported functional scores, the Oxford Knee Score (OKS) and Forgotten Joint Score (FJS), to measure the functional status of the knee. RESULTS: In total, 267 primary rotating hinge knee arthroplasties in 242 patients were performed in two centres. The three major indications were axial malalignment (valgus/varus > 15°), 87/267 (33%), persistent ligamentous instability (28%) and neuromuscular disorders (12%). 184 patients with 202 primary rotating hinge knee arthroplasties could be included that provided data of the self-reported outcome measures (OKS and FJS). A mean OKS score of 37.71 (± 9.23) and a mean FJS score of 63.65 (± 31.01) could be obtained. CONCLUSION: This large clinical study suggests that constrained devices provide the best results when treating bone-on-bone tricompartimental osteoarthritis of the knee with severe axial deviation (valgus/varus > 15°) and/or persistent ligamentous instability.

A case of an atraumatic implant failure after primary rotating-hinge total knee arthroplasty.

Rotating-hinge knee implants are fully constrained knee prostheses commonly used for revision total knee arthroplasty. Nevertheless, rotating-hinge devices have been increasingly utilized in primary setting. Complications are inevitable in orthopedic surgery, however, implant breakage after RHK arthroplasty has been rarely described in medical literature. We present a rare case of 70-year-old Caucasian, male patient who suffered an atraumatic femoral stem breakage in a primary NexGen ® Rotating Hinge Knee (Zimmer-Biomet ® , Warsaw, IN, USA).

Avulsion Fracture of the Anterior Intercondylar Eminence in an Eight-year-old Child: ACase Report.

INTRODUCTION: Avulsion fractures of the tibial intercondylar eminence are rare and occur mostly in children. The purpose of this paper is to present a case of this rare pathology and to underline the importance of early diagnosis. CASE REPORT: A male 8-year-old child presented with pain in his left knee and difficulties to walk after a combined injury of falling and contact trauma. Radiographic studies with conventional X-ray and computed tomography (CT) scan depicted a fracture of the intercondylar eminence. In this Type II fracture according to the classification of Meyers and McKeever, an operative treatment with knee arthroscopy was established to remove the loose bone. Post-operative, the knee was immobilized in extension for 4 weeks. Physiotherapy was initiated immediately after surgery. The follow-up CT scan 6weeks after injury showed a starting consolidation and the magnetic resonance imaging scan 8 weeks after injury a complete consolidation of the fracture. CONCLUSION: Hyperflexion and rotation trauma result rather in bony avulsions than in ligamentous lesions in pediatric patients. Early diagnostic examination with conventional X-ray and CTscans is performed to not miss concomitant injuries. Depending on the type of eminentiaintercondylaris fracture, an operative or conservative treatment is indicated.