Flat feet are an important cause of foot problems in children. The flexible flat foot is the most common form and is normally physiological and asymptomatic. Further assessment is necessary when a symptomatic flat foot persists. Surgical interventions are indicated when conservative therapies have failed. The Kalix arthroereisis is a surgical option and is placed in the subtalar joint of the foot, thereby preventing hyperpronation, and stabilizes the foot against excessive movements. The purpose of this study was to evaluate the functional and radiological outcomes of pediatric patients who had undergone a Kalix implantation for the treatment of a symptomatic flexible flat foot. Patient files of our institution were searched for patients who underwent a Kalix implantation between 2009 and 2014. Sixteen patients (26 feet) with symptomatic flexible flat feet were clinically and radiographically evaluated in this retrospective study. The calcaneal pitch and Meary”s angle were measured on the pre-, and postoperative follow-up radiographs and patient satisfaction survey was performed at follow-up to gain insight into functional outcome and satisfaction after the intervention.Purpose
Methods
Total ankle replacement (TAR) is increasingly used in the treatment of end-stage ankle arthropathy, but much debate exists about the clinical result. The goals of present study are: 1) to provide an overview of the clinical outcome of 58 TAR's in a single centre and 2) to assess the association between radiological characteristics and clinical outcome. We reviewed a prospective included cohort of 58 TAR's in 54 patients with a mean age of 66.9 (range 54–82) and a mean follow-up of 21.6 months (range 1.45–66.0). The TAR's where performed by a single surgeon in a single centre (MUMC) between 2010 and 2015, using the CCI ankle replacement. A standard surgical protocol and standardized post-op rehabilitation was used. Patients were followed-up pre-op and at 1 day, 6 weeks, 3–6–12 months and yearly thereafter post-op. The AOFAS and range of motion (ROM) were assessed and all complications, re-operations and the presence of pain were recorded. Radiographic assessment consisted of the estimation of prosthesis alignment, migration, translation and radiolucent lines using the Rippstein protocol (1). The clinical outcome was compared with a systematic review of TAR outcome. Ten intra-operative complications occurred and 9 were malleolar fractures. Post-operative complications occurred in 20 out of the 54 patients (37.0%). Impingement (5/54 patients), deep infection (4/54 patients), delayed wound healing (3/54 patients) and minor nerve injuries (3/54 patients) were the most frequently recorded. 18 patients (31.0%) underwent one or more re-operations and 12 of these 18 patients underwent a component revision (mostly the PE insert) or a conversion to arthrodesis. Despite the complications and revisions, the functional outcome improved. Radiologically 15.8% of the TAR's were positioned in varus and 1.8% in valgus. Migration in the frontal and sagittal plane is seen in 3 and 2 TAR's respectively. Radiolucency is significantly increasing with the follow-up time (p=0.009). Migration in the frontal plane is significantly associated with conversion to arthrodesis (p=0.005) and migration in the sagittal plane to revision of a component or conversion to arthrodesis (p=0.04). Finally, pain is significantly associated with re-operations (p=0.023) and complications (p=0.026). Remarkable is that the clinical outcome is independent of the direct post-op alignment of the TAR. The complication-, re-operation and revision or conversion to arthrodesis rates makes the clinical outcome of TAR still questionable favourable. Especially the complication and re-operation incidences are greater than found in the systematic review. However, it is remarkable that the minor complications and re-operations not related to the TAR are not often mentioned in the literature. Radiographic characteristics could be of value in predicting this clinical outcome and thereby influence the post-operative handling. In conclusion, our results show relatively high incidences of complications (37.0%) and re-operations (31.0%) when minor complications and re-operations are included. TAR clinical outcome can be predicted by radiographic migration characteristics and pain.
An alternative way to assess three dimensional skin motion artefacts of kinematic models is presented and applied to a novel kinematic foot model. Largest skin motion is measured in the tarsal region. Motion capture systems are being used in daily clinical practise for gait analysis. Last decade several kinematic foot models have been presented to gain more insight in joint movement in various foot pathologies. No method is known to directly measure bone movement in a clinical setting. Current golden standard is based on measurement of motion of skin markers and translation to joint kinematics. Rigid body assumptions and skin motion artefacts can seriously influence the outcome of this approach and rigorous validation is required before clinical application is feasible. Validation of kinematic models is currently done via comparison with bone pin studies. However, these studies can only assess major bones in a highly invasive way; another problem is the non-synchronous measurement of skin markers and bone pins. Recently the Glasgow Maastricht kinematic foot model, which comprises all 26 foot segments, has been presented. To validate the model we propose a novel non-invasive method for the assessment of skin motion artefact, involving loaded CT data.Summary Statement
Introduction
