Abstract. OBJECTIVES. Cam femoroacetabular impingement (FAI – femoral head-neck deformity) and developmental dysplasia of the hip (DDH – insufficient acetabular coverage) constitute a large portion of adverse hip loading and early degeneration. Spinopelvic anatomy may play a role in hip stability thus we examined which anatomical relationships can best predict range of motion (ROM). METHODS. Twenty-four cadaveric hips with cam FAI or DDH (12:12) were CT imaged and measured for multiple femoral (alpha angles, head-neck offset, neck angles, version), acetabular (centre-edge angle, inclination, version), and spinopelvic features (pelvic incidence). The hips were denuded to the capsule and mounted onto a robotic tester. The robot positioned each hip in multiple flexion angles (Extension, Neutral 0°, Flexion 30°, Flexion 60°, Flexion 90°); and performed internal-external rotations to 5 Nm in each position. Independent t-tests compared the anatomical parameters and ROM between FAI and DDH (CI = 95%). Multiple linear regressions determined which anatomical parameters could predict ROM. RESULTS. The FAI group demonstrated restricted ROM in deep hip flexion, with DDH showing higher ROM in Flexion 30° (+20%, p = 0.03), 60° (+31%, p = 0.001), and 90° (+36%, p = 0.001). In Neutral 0° and Flexion 30°, femoral neck and version angles together predicted ROM (R. 2. = 60%, 58% respectively); whereas in Flexion 60°, pelvic incidence and femoral neck angle predicted ROM (R. 2. = 77%). In Flexion 90°, pelvic incidence and radial alpha angle together predicted ROM (R. 2. = 81%), where pelvic incidence alone accounted for 63% of this variance. CONCLUSIONS. Pelvic incidence is essential to predict hip ROM. Although a cam deformity or acetabular undercoverage can elevate risks of labral tears and progressive joint degeneration, they may not be primary indicators of restrictive hip impingement or dysplastic instability. Better delineating additional spinopelvic characteristics can formulate early diagnostic tools and improve opportunities for nonsurgical management. Declaration of Interest. (b) declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported:I declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project

Background. Acetabular labral tears can cause pain and microinstability and are the most common indication for hip arthroscopy. Hip labral repair demonstrates better clinical outcome scores at a mean of 3.5 years post surgery than labral excision and tends to be performed in a younger age group. While different labral stitch configurations are possible, the most frequently used are a mattress stitch passed though the hip labrum at its widest part, or a simple loop surrounding the labrum. To determine the strength of variousrepair techniques and the impact suture passer sizesonhip labrum failure after cyclic loading. Methods. 35 unattached fresh-frozen bovine hip labrums were assigned to 5 repair techniques (7 specimens each): Group 1: horizontal mattress using a penetrating grasper; Group 2: vertical mattress using a penetrating grasper; Group 3: vertical mattress using asuture lasso; Group 4: Oblique repair using a penetrating grasper; Group 5: vertical mattress using a penetrating grasper and monopolar radio frequency device. Using a materials testing machine and after a 10N preload, each contruct was subjected to 20 cycles at 5N–80N. Cyclic elongation, peak-to-peak displacement, ultimate failure load, stiffness, and failure mode were recorded. Results. Group 1 (249N) had lower ultimate load than groups 2 (277N), 3 (289N), 4 (281N), and 5 (278N) (p<0.05) and higher peak to peak displacement, cyclic elongation (14mm) than group 3 (12mm) (p<0.05). Group 2 (15mm) had higher peak to peak displacement than group 3 (p<0.05). Group 3 had lower cyclic elongation and peak to peak displacements than group 4 (p<0.05). Conclusion. A horizontal mattress hip labrum repair demonstrates lower ultimate failure load than a vertical mattress or an oblique suture repair. A smaller diameter suture passing device demonstrated less cyclic displacement but no difference in ultimate failure load than a large diameter device. Radiofrequency treatment did not have any effect on the strength of the suture repair configuration. Level of evidence. Level 5

Objectives

The aim of this study was to systematically review the literature on measurement of muscle strength in patients with femoroacetabular impingement (FAI) and other pathologies and to suggest guidelines to standardise protocols for future research in the field.

Objectives

All-suture anchors are increasingly used in rotator cuff repair procedures. Potential benefits include decreased bone damage. However, there is limited published evidence for the relative strength of fixation for all-suture anchors compared with traditional anchors.

Recently, femoroacetabular impingement has been recognised as a cause of early osteoarthritis. There are two mechanisms of impingement: 1) cam impingement caused by a non-spherical head and 2) pincer impingement caused by excessive acetabular cover. We hypothesised that both mechanisms result in different patterns of articular damage. Of 302 analysed hips only 26 had an isolated cam and 16 an isolated pincer impingement. Cam impingement caused damage to the anterosuperior acetabular cartilage with separation between the labrum and cartilage. During flexion, the cartilage was sheared off the bone by the non-spherical femoral head while the labrum remained untouched. In pincer impingement, the cartilage damage was located circumferentially and included only a narrow strip. During movement the labrum is crushed between the acetabular rim and the femoral neck causing degeneration and ossification.

Both cam and pincer impingement lead to osteoarthritis of the hip. Labral damage indicates ongoing impingement and rarely occurs alone.

Objectives

Excessive acetabular coverage is the most common cause of pincer-type femoroacetabular impingement. To date, an association between acetabular over-coverage and genetic variations has not been studied. In this study we investigated the association between single nucleotide polymorphisms (SNPs) of paralogous Homeobox (HOX)9 genes and acetabular coverage in Japanese individuals to identify a possible genetic variation associated with acetabular over-coverage.