Relationship between thoracic alignment asymmetry and hip joint alignment during isometric hip rotation: a comparison of femoral head deviation between left and right sides.

Only healthy adult men were studied, with an average age of 27 and no pain, deformity or relevant history. The authors say plainly that data from people with actual disease conditions are still needed, and that pain and deformity could change the measurements. Everyone was measured once, at rest and during a single isometric task. No treatment was given or tested, so the study cannot say whether changing thoracic alignment changes hip alignment or helps anything. Only two of the 26 men had a thorax deviated to the right, so the comparison between left-deviated and right-deviated groups rests almost entirely on one group. Bone shape was not imaged. The authors list this as a limitation and note that hip coverage and anteversion angles have been linked to femoral head position before, so they cannot say how much of what they saw comes from bone rather than from soft tissue. The paper's own numbers do not line up on direction. The methods say a negative value means the femoral head is sitting forward, but the table gives the right side the larger negative number while the results text says the left side sat further forward. Which side is truly more anterior is hard to pin down from the text as printed. The muscle explanation offered for the findings, that the left and right rotator muscles pulled the socket in different directions, is the authors' interpretation from a Discussion that tested no muscle activity. No muscle was measured.

The authors declare no conflict of interest regarding the publication of this article. The paper reports no funding source and no statement about who designed the study or handled the data.

Do not read this as evidence that correcting a ribcage asymmetry will change a hip, prevent hip disease or help hip pain. The study measured 26 healthy men once, at rest and during one isometric task, and gave no treatment, so it can only show that two measurements moved together in people who had no hip problem to begin with. It also cannot say which came first.