The KOOS-12 shortform shows no ceiling effect, good responsiveness and construct validity compared to standard outcome measures after total knee arthroplasty.

Purpose: To investigate the validity, responsiveness and ceiling effect of the recently introduced KOOS-12 and compare its performance to the KOOS, OKS, WOMAC and UCLA activity scales.

Methods: Patients from an independent multicentre study examining a medially stabilized knee system prospectively completed the KOOS, OKS, WOMAC and UCLA preoperatively and at 1 year postoperatively. KOOS-12 scores were calculated from the full length KOOS data.

The kinematic relationship between sitting and standing posture and pelvic inclination and its significance to cup positioning in total hip arthroplasty.

Purpose: The aim of this study is to describe the influence of sitting and standing posture on sagittal pelvic inclination in total hip replacement patients to assist with correct acetabular component positioning.

Methods: Lateral radiographs of the pelvis and lumbar spine in sitting and standing positions were extracted. Pelvic tilt was measured using the vertical inclination of a line from the anterior superior iliac spine (ASIS) to pubic tubercle.

The effect of obesity on the clinical, functional and radiological outcome of cementless total hip replacement: a case-matched study with a minimum 10-year follow-up.

1420 primary cementless THRs with a minimum follow-up of 10-years were stratified according to BMI: non-obese (BMI<30kg/m(2)) and obese (BMI≥30kg/m(2)). Median age at surgery was younger in obese patients (P<0.001).

Squeaking: Current knowledge and how to avoid it.

This review aims to update the reader with current thinking and research related to the well documented phenomenon of squeaking hip arthroplasties. The etiology of squeaking is multifactorial and still not well understood. We aim to share our own experience and views on the combination of factors we believe increases the likelihood of squeaking, along with mechanisms by which the sound may be generated.