Kalisvaart, Michael M.

AbstractPurposeThe purpose of this study was to review the results of patellofemoral arthroplasty (PFA) performed by a single surgeon at a single institution in order to determine factors associated with clinical outcomes and progression of tibiofemoral degenerative joint disease.MethodsSixty‐one patients with isolated patellofemoral osteoarthritis were treated with a PFA by a single surgeon between 2003 and 2009. Fifty‐nine patients were available for analysis with a mean follow‐up of 4 years (range 2–6 years). Patients were evaluated by measuring range of motion and with the use of the Knee Society clinical rating system, the Tegner Activity Level Scale, and the UCLA Activity Score. In addition, preoperative radiographs were evaluated for patellofemoral and tibiofemoral compartment osteoarthritis and presence of trochlear dysplasia, and post‐operative radiographs were reviewed for progression of tibiofemoral degenerative arthritis. Furthermore, multivariate statistical methods were applied to study factors that had potential to influence the final outcome.ResultsThere was no statistically significant association between age, gender, history of prior knee surgery, patellar height, patellofemoral osteoarthritis severity, patellar and femoral component size, or performance of lateral release with patient pain and function (as measured by the Knee Society scores) or progression of tibiofemoral joint osteoarthritis at final follow‐up. Increased preoperative body mass index (BMI) was associated with lower post‐operative Knee Society function scores (p = 0.03). Patients with preoperative trochlear dysplasia had significantly less radiographic evidence of tibiofemoral joint osteoarthritis progression compared with patients without trochlear dysplasia at final follow‐up (p < 0.0001).ConclusionIn this study, patients with preoperative radiographic evidence of trochlear dysplasia experienced less progression of tibiofemoral degenerative joint disease than patients without trochlear dysplasia at a mean follow‐up of 4 years.Level of evidenceIV.

AbstractPurposeAssessment of hip internal rotation (IR) is a critical element in the evaluation of a painful hip, yet there currently exists no consistent method of determining this measurement. The purpose of this study is to report the intra‐rater and inter‐rater reliability of active and passive hip IR measurement using a digital inclinometer.MethodsTwenty‐five subjects (8 men, 17 women) with asymptomatic hip joints, and no known pathology between the ages of 22 and 42 participated. Two examiners measured hip IR for each subject using a digital inclinometer while visually monitoring pelvic motion. Measurements included passive IR, active IR, and active IR while internally rotating both legs simultaneously. Statistical analysis was performed including intra‐rater and inter‐rater reliability.ResultsThere was no significant difference in measured IR values. Mean range of motion values for all techniques and both examiners ranged from 30.7° to 32.8°. Intra‐rater reliability for examiner 1 ranged from 0.84 to 0.92. Inter‐rater reliability ranged from 0.89 to 0.93. Of the methods utilized, active IR of a single leg was the most responsive technique with a minimal detectable change value of 5.4°.ConclusionsClinical assessment of hip IR range of motion can be performed efficiently and reliably with a digital inclinometer along with visual monitoring of the pelvis for unwanted motion. Findings from this study support unilateral active hip IR in a seated position as a reliable and responsive technique for obtaining hip IR measurements.Level of evidenceIII.