Automatic initial contact detection during overground walking for clinical use.

The division of gait into cycles is crucial for identifying deficits in locomotion, particularly to monitor disease progression or rehabilitative recovery. Initial contact (IC) events are often used to separate movement into repetitive cycles yet automatic methods for IC identification in pathological gait are limited in both number and capacity. The aim of this work was to develop a more precise algorithm in IC detection.

Collateral ligament length change patterns after joint line elevation may not explain midflexion instability following TKA.

Midflexion instability (MFI) after TKA is a phenomenon often described as varus-valgus instability between 30° and 45° knee flexion. The exact mechanisms causing MFI remain unclear, but elevation of the joint line (JLE) may be one possible cause. In an in silico approach using 4 subject specific musculoskeletal models, the length change patterns of the collateral ligaments during knee flexion (relative to the extended knee) were calculated for the anatomically reconstructed joints as well as for JLEs of 5 and 10mm.

Joint line elevation in revision TKA leads to increased patellofemoral contact forces.

One difficulty in revision total knee arthroplasty (TKA) is the management of distal femoral bone defects in which a joint line elevation (JLE) is likely to occur. Although JLE has been associated with inferior clinical results, the effect that an elevated joint line has on knee contact forces has not been investigated. To understand the clinical observations and elaborate the potential risk associated with a JLE, we performed a virtual TKA on the musculoskeletal models of four subjects.