Restoring mobility after stroke: first kinematic results from a pilot study with a hybrid drop foot stimulator.

OBJECTIVE: The objective was to obtain first insights into the kinematic and kinetic walking patterns resulting from an implanted functional electrical stimulation system in subjects with a drop foot caused by stroke. METHODS: Four subjects who experienced a stroke were chosen due to a comparatively long/short time after surgery and young/old at the stroke event were examined retrospectively with gait analysis. Kinematics and kinetics of normal walking were assessed in comparison with and without activated drop foot stimulation. RESULTS: In general, an improvement regarding spatiotemporal parameters as a result of the stimulation could be observed. Walking speed was increased by 45 % and stride length by 22 % after a mean usage of 7 (2-14) months, whereas both younger subjects improved significantly more. Dorsiflexion increased in all subjects on average from 1.3° to 11.6° during initial contact as well as from 11.3° to 17.0° during mid-swing and therefore implies an advantage of around 5.5 inch foot clearance. Pathologic elements like knee hyperextension during loading response and mid-stance, leg circumduction during swing or the increased hip flexion of the contralateral leg during mid-stance could be in general adjusted with stimulation. CONCLUSION: An implantable functional electrical stimulation system seems to be a promising treatment of drop feet following strokes. Further clinical investigations are necessary to confirm these first insights.

Articulating spacers compared to fixed spacers for the treatment of infected knee arthroplasty: A follow-up of 37 cases.

BACKGROUND: The standard treatment of a periprosthetic infection after TKA involves a two-stage reimplantation with the intermittent implantation of spacers. Different designs of spacers have been described; currently articulating spacers and fixed spacers are used. The aim of the present study is to compare the advantages/disadvantages of the different spacers. PATIENTS AND METHODS: In this retrospective study we analyzed 37 cases after revision surgery of infected TKA. All patients that received spacers as part of the two-stage reimplantation were included. Exclusion criteria were massive bone loss prior to revision, because the implantation of a mobile spacer would not have been possible. RESULTS: The average ROM was 98.0 (± 14.9) degrees in the articulating spacer group (group 1) and 79.3 (± 22.5) in the group that received the fixed spacers (group 2) before revision surgery started. At a late follow up the average ROM for group 1 was 102.0 (± 8.4) and 79.0 (± 26) for group 2. CONCLUSION: The use of articulating spacers in the two-stage revision for infected total knee arthroplasty is a safe alternative to fixed spacers, that equally preserves ligament balancing and has equal infection eradication rates. A long term improvement of the range of motion following reimplantation of the new joint was, however, not observed.

[Complete rupture of the peroneal nerve by knee distortion]. / Komplette N.-peronaeus-Ruptur bei Kniedistorsion.

This report describes a case of complete rupture of the peroneal nerve as a consequence of low velocity trauma. A 54-year-old physically fit patient suffered a complex trauma with complete nerve discontinuity as a result of knee joint distortion without external force. The initial medical findings were unremarkable, in particular neither the accident medical history nor the initial sensitivity impairment suggested the presence of serious knee damage; however, during clinical diagnostics a complex trauma with rupture of the peroneal nerve was found. Accordingly, an extensive revision with nerve suturing was carried out.

[Taking the anamnesis with a questionnaire - safe and effective]. / Die Anamneseerhebung mittels Fragebogen - sicher und effektiv.

INTRODUCTION: The anamnesis is essential for the treatment of any patient. On the other hand, the data are often of poor quality. The aim of the study was to work out whether a questionnaire which is filled out by the patient him-/herself is a reasonable tool for data acquisition. METHODS: In a level-IV trauma centre the data acquisition of 50 consecutive patients was performed with a questionnaire which was checked by a doctor. Excluding criteria were an age < 18 years, previous treatment in the clinic, a transfer from an external clinic or a caring institution and a dementia. The results were compared with the data of the 50 patients prior to the study start. RESULTS: We collected data about the general doctor, diseases, allergies, tobacco usage, drugs, operations and the familial situation. In all 7 fields the questionnaire raised more data than the oral survey; in 4 sections the difference was significant, in 3 (p > 0.05). DISCUSSION: A questionnaire is a reasonable, time-sparing tool for data acquisition of the individual anamnesis in a surgical clinic.

[Comparison of stability of plate fixateurs with parallel and oblique screw directions]. / Vergleich der Ausbruchfestigkeit winkelstabiler Plattensysteme bei paralleler und divergierender Schraubenlage.

INTRODUCTION: One of the main failure mechanisms of modern plate fixateurs is the tearing of the whole plate-screw construct out of the osteoporotic bone. The aim of this study was to show whether an oblique screw placement can improve the fixation of the plate to the bone. METHODS: A steel probe was fixed to a synthetic bone (Fa. Sawbones) with standard titanium fixed-angle screws in parallel and 55° oblique positioning. We tested the static tear force and the dynamic stability (force distance 1.4 or 1.6 mm, 610 and 900 N, frequency of force shift of 560 or 380/min). Endpoint was a visible tear of the artificial bone. In addition we performed a morphological analysis of the torn fragments. RESULTS: The maximal tear force was 2.04 kN (1.95-2.13) for oblique and 2.66 kN (2.55-2.77) for parallel placement (p < 0.05). With a parallel positioning a higher number of force shifts were performed before a visual tear appeared. With parallel positioning the screw canal was torn with an intact surrounding corticalis; in oblique positioning the threads remained intact, the corticalis was torn out with a wedge. DISCUSSION: An oblique screw positioning does not result in a higher tear force in modern plate fixateurs.

[Outcome 4 years after isolated single-bundle posterior cruciate ligament reconstruction]. / Vierjahresergebnisse nach Isolierter Hinterer Kreuzbandrekonstruktion in Einbündeltechnik.

BACKGROUND: The purpose of this study was to evaluate the clinical and radiological results after isolated reconstruction of the posterior cruciate ligament (PCL) using semitendinosus (ST) and gracilis (GT) tendon grafts with the arthroscopic single-bundle technique. MATERIALS AND METHODS: Following PCL reconstruction using the single-bundle technique performed between 2002 and 2005, 14 patients (2 women, 12 men) prospectively underwent a standardized follow-up examination after an average postoperative time of 4 years. All patients included in this study had isolated insufficiency of the PCL and symptomatic instability. The exclusion criteria were the presence of a complex knee joint instability and the implementation of additional stabilizing measures or another method of PCL reconstructive surgery. The mean follow-up time was 47.2 ± 8.7 months. Preoperative and postoperative stress radiographs were taken using the Telos stress instrument in order to evaluate the posterior translation. Knee joint function and degree of activity were recorded using the Tegner activity score, the subjective IKDC score and the overall IKDC score. RESULTS: The posterior tibial translation of 10.1 ± 1.7 mm had an overall average improvement to a postoperative value of 4.6 ± 2.3 mm (p < 0.001). The patients showed a significant improvement in the Tegner activity score from an average 2.7 ± 0.8 points to 5.7 ± 1.3 points (p < 0.001). Evaluation of the subjective IKDC showed a significant improvement from a preoperative score of 41.32 ± 11.23 points to a postoperative score of 65.08 ± 13.51 points (p < 0.001). In total, 10 patients (71.5%) exhibited a normal or nearly normal outcome. According to the objective IKDC score, 4 patients (28.5%) were categorized as moderate. CONCLUSION: The above mentioned reconstruction technique can achieve a stable knee function in patients with isolated PCL insufficiency. The isolated single-bundle PCL reconstruction offers a medium-term improvement regarding the activity level and stability of the knee joint.