Synovial cells from the subacromial bursa in patients with rotator cuff tears are a superior cell source in vitro, suggesting that mesenchymal stem cells from this tissue could be good candidates for biological augmentation of rotator cuff repair.

Preoperative predictors of poorer outcomes from hip arthroscopic labral preservation, capsular plication, and cam osteoplasty in the setting of BDDH are age ≥42 years old, broken Shenton line, osteoarthritis, Tönnis angle ≥15°, and VCA angle ≤17° on preoperative radiographs. Intraoperative predictors of poorer outcomes are severe acetabular chondral damage and even mild femoral chondral damage. Although the patients in the setting of BDDH may have good outcomes from isolated hip arthroscopy, caution is suggested for those with the aforementioned risk factors.

Purpose To develop a statement on the diagnosis, classification, treatment, and rehabilitation concepts of posterolateral corner (PLC) injuries of the knee using a modified Delphi technique. Methods A working group of three individuals generated a list of statements relating to the diagnosis, classification, treatment, and rehabilitation of PLC injuries to form the basis of an initial survey for rating by an international group of experts. The PLC expert group (composed of 27 experts throughout the world) was surveyed on three occasions to establish consensus on the inclusion/exclusion of each item. In addition to rating agreement, experts were invited to propose further items for inclusion or to suggest modifications of existing items at each round. Pre‐defined criteria were used to refine item lists after each survey. Statements reaching consensus in round three were included within the final consensus document. Results Twenty‐seven experts (100% response rate) completed three rounds of surveys. After three rounds, 29 items achieved consensus with over 75% agreement and less than 5% disagreement. Consensus was reached in 92% of the statements relating to diagnosis of PLC injuries, 100% relating to classification, 70% relating to treatment and in 88% of items relating to rehabilitation statements, with an overall consensus of 81%. Conclusions This study has established a consensus statement relating to the diagnosis, classification, treatment, and rehabilitation of PLC injuries. Further research is needed to develop updated classification systems, and better understand the role of non‐invasive and minimally invasive approaches along with standardized rehabilitation protocols. Level of evidence Consensus of expert opinion, Level V.

Purpose. To determine the characteristics of MSCs from hip and compare them to MSCs from knee. Methods. Synovial tissues were obtained from both the knee and the hip joints in 8 patients who underwent both hip and knee arthroscopies on the same day. MSCs were isolated from the knee and hip synovial samples. The capacities of MSCs were compared between both groups. Results. The number of cells per unit weight at passage 0 of synovium from the knee was significantly higher than that from the hip (P < 0.05). While it was possible to observe the growth of colonies in all the knee synovial fluid samples, it was impossible to culture cells from any of the hip samples. In adipogenesis experiments, the frequency of Oil Red-O-positive colonies and the gene expression of adipsin were significantly higher in knee than in hip. In osteogenesis experiments, the expression of COL1A1 and ALPP was significantly less in the knee synovium than in the hip synovium. Conclusions. MSCs obtained from hip joint have self-renewal and multilineage differentiation potentials. However, in matched donors, adipogenesis and osteogenesis potentials of MSCs from the knees are superior to those from the hips. Knee synovium may be a better source of MSC for potential use in hip diseases.

Patients with a broken Shenton line, FNS angle >140°, CE angle <19°, or BMI >23 kg/m(2) at the time of surgery are not good candidates for the arthroscopic management of DDH.