The aim of this study was to assess the relationship between Q-angle and lower extremity alignment in women with unilateral patellofemoral pain syndrome (PFPS).
Eighty-five women with unilateral ...patellofemoral pain participated in the study, with each subject acting as their own internal control using the unaffected limb. Lower extremity alignment and Q-angles of the affected and unaffected knees were compared.
There was a significant difference in the Q-angle between the affected (19.61±4.35) and the unaffected (17.63±4.29) side (p=0.00). There was also a significant difference in the lateral distal femoral angle (LDFA) (81.00±2.58 vs. 81.83±3.03; p=0.03) and no significant difference in the medial proximal tibial angle (MPTA) (87.88±2.63 vs. 87.60±3.29; p=0.51) between the affected and the unaffected side. There was no relationship between the Q-angle and LDFA (r=0.001, p=0.99), and MPTA (r=-0.051, p=0.64) in the affected side of the patients. There was also no relationship between the Q-angle and LDFA (r=0.179, p=0.64), and MPTA (r=-0.146, p=0.18) in the unaffected side of the patients.
Increased Q-angle and decreased LDFA may be associated with PFPS although cause or effect cannot be established. There was no relationship between the Q-angle and lower extremity malalignment. Large prospective longitudinal studies are needed to detect changes in the femoral anteversion and toe-in gait and to establish if these features are a cause of PFPS.
The size and shape of the acetabulum and of the femoral head influence the injury tolerance of the hip joint. The aim of this study is to quantify changes in acetabular cup geometry that occur with ...age, gender, height, and weight. Anonymized computed tomography (CT) scans of 1,150 individuals 16+ years of age, both with and without hip trauma, were used to describe the acetabular rim with 100 equally spaced points. Bilateral measurements were taken on uninjured patients, while only the uninjured side was valuated in those with hip trauma. Multinomial logistic regression found that after controlling for age, height, weight, and gender, each 1 degree decrease in acetabular anteversion angle (AAA) corresponded to an 8 percent increase in fracture likelihood (p<0.001). Age, weight, and gender were found to influence anteversion angle significantly, with each 10 years in age increasing AAA by 1.07 degrees, each 10 kg of weight decreasing AAA by 0.45 degrees, and being female resulting in 1.42 degrees greater AAA than males. Height was not found to relate significantly to AAA after other anthropometric factors were controlled for. Height, age, and weight, however, correlated with femoral head radius, thus establishing a relationship with acetabular rim size independent of rim shape. A parametric model of the 3D acetabular rim landmark points is reported, allowing for the creation of individualized acetabular geometry for any given age, gender, height, and weight. A custom-built tool to produce such geometry programmatically is also provided.
We performed a systematic literature review to evaluate the role of the transverse acetabular ligament as a reference aid when determining acetabular component anteversion in total hip arthroplasty. ...We conducted a literature search in the MEDLINE, EMBASE and Pubmed databases using the key words 'transverse acetabular ligament' and 'arthroplasty'. Four studies published between 2006 and 2011, reporting on 1,217 procedures met our inclusion and exclusion criteria and were eligible for final evaluation. Outcome measures were the ability to identify the transverse acetabular ligament, anteversion of the acetabular component and dislocation rate. The methodological quality of the studies was variable and they were not homogenous enough for metaanalysis. We found that there was good evidence for the use of the transverse acetabular ligament in terms of accuracy of acetabular component anteversion. However, the ligament could not be routinely identified intra-operatively and other methods of determining the correct anteversion are recommended in this situation. The dislocation rate using this technique was low but it must be stressed that the cause of postoperative dislocation in total hip arthroplasty is multi-factorial and cannot solely be attributed to acetabular component orientation.