To analyse the distribution of osteoarthritis of the knee, to determine what proportion of patients may be suitable for a partial knee replacement and finally to assess the risk of wear progression. The intra-operative articular surface mappings were collected for 250 consecutive patients undergoing knee arthroscopy. Patients were graded using the Outerbridge Classification. Radiographs including antero-posterior standing, postero-anterior flexion (Rosenberg), lateral and skyline views were graded (Kellgren and Lawrence) and compared with the arthroscopic findings. 13.3% of knees showed ‘isolated’ medial disease of Outerbridge Grade 3 or worse. Isolated lateral disease was noted in 1.4%, patello-femoral disease in 24.3%, bi-compartmental (Medial/PFJ) disease in 30.9% with tibio-femoral and tri-compartmental disease in 15.2%. The combination of lateral and patello-femoral disease was seen in 14.8%. The mean age of patients with tri-compartmental disease (60.9 years) was greater than the mean age of those suffering with osteoarthritis limited to one or two compartments (54 years) Radiological analysis revealed AP views had only 66% sensitivity and 73% specificity for the presence of Grade 3/4 lesions in the medial compartment. Rosenberg views had 73% sensitivity and 83% specificity. Skyline views had a sensitivity of 56% and 100% specificity.Statement of purpose
Summary of methods used and results
SPECT/CT might be a promising diagnostic modality in patients with painful total knee arthroplasty. It was the purpose of our study to introduce a novel standardised SPECT/CT algorithm for assessing patients with painful primary total knee arthroplasty and to evaluate its clinical applicability and inter- and intra-observer variation and reliability. A novel SPECT/CT localisation scheme, which consists of 9 tibial, 9 femoral and 4 patellar regions on standardised transverse, coronal, and sagittal slices was introduced. It was assessed in 18 consecutive patients with painful knees after total knee arthroplasty. The localisation and level of the tracer uptake on SPECT/CT were noted using a color coded 10 steps graded scale (0-100). The inter and intra-observer reliability were assessed. The femoral and tibial prosthetic component position was assessed in the CT images after 3D reconstruction and aligning them to standardised frames of reference. The average root mean square difference±standard deviations and ranges of these measured angles are presented along with the intraclass correlation coefficients for inter- and intraobserver reliability.Introduction
Methods
