Innervation zone locations in 43 superficial muscles: Toward a standardization of electrode positioning

Introduction: We describe the innervation zone (IZ) location in 43 muscles to provide information for appropriate positioning of bipolar electrodes for clinical and research applications. Methods: The IZ was studied in 40 subjects (20 men and 20 women) using multichannel surface electromyography (sEMG). Signal quality was checked visually to identify motor unit action potentials and estimate muscle fiber conduction velocity. Results: Results in 33 muscles were classified as excellent or good, because it was possible to identify an area which is favorable for appropriate positioning of an electrode pair without the need to previously determine the IZ location. Conclusions: Knowledge of IZ location will increase standardization and repeatability of sEMG measures. Muscle Nerve 49 :413–421, 2014     

The effects of femoral component design on the patello-femoral joint in a PS total knee arthroplasty

Introduction

Anterior knee pain following TKA performed utilizing the PFC Sigma system still represents a cause of failure. The purpose of this study was to evaluate whether or not a recent change in the femoral design (PFC Sigma PS) had a positive impact on the patello-femoral complication rate.

Materials and methods

A consecutive series of 100 TKA using the PFC Sigma PS system was followed prospectively for a minimum of 3 years. All patellae were replaced and a standard lateral release was never performed. Radiographic analysis following the Knee Society Score (KSS) included antero-posterior weight-bearing, lateral and bilateral axial radiographs. TKA rotational alignment was recorded at the final follow-up in 30 consecutive knees by performing a CT evaluation.

Results

Good to excellent clinical results according to the KSS were achieved in 94 % of the knees. Survival without need of reoperation for any reason was 98 % at 3 years minimum follow-up; two reoperations were done for removal of fibromatous intra-articular tissue (“Clunk syndrome”). There were no revisions for septic or aseptic loosening of the components. The mean ROM improved from 104° preoperatively to 115° (97°–132°) postoperatively: postoperative flexion was 120° or more in 58 % of the knees. Severe anterior knee pain was present in 9 % of patients. Radiographic evaluation showed 90 knees with a tibio-femoral anatomical axis between 8° and 2° of valgus (±3° from the intraoperative goal). CT evaluation of 30 consecutive knees showed that the femoral component positioning in relationship to the trans-epicondylar axis had only 2.80° of external rotation (±2.10°) with respect to a planned external rotation of 3°. This difference was statistically significant.

Conclusions

Although the PFC Sigma PS system provides good and predictable results for tricompartmental arthritis of the knee, anterior mechanism complications still represent a reason for dissatisfaction in a substantial group of patients.     

Conservative surgical and microsurgical techniques for the management of dental implants that impinge on the inferior alveolar nerve

Loss of sensation in the lip after insertion of an implant is annoying. The aim of this paper was to describe two techniques for management of osseointegrated dental implants that impinge on the mandibular nerve, the purpose of which is to improve sensation without unscrewing the dental implant.     

Intracardiac Versus Transesophageal Echocardiographic Guidance for Left Atrial Appendage Occlusion: The LAAO Italian Multicenter Registry

Objectives

This study sought to evaluate the feasibility, safety, and efficacy of intracardiac echocardiography (ICE)–guided versus transesophageal echocardiography (TEE)–guided left atrial appendage occlusion (LAAO) by the use of Amplatzer Cardiac Plug or Amulet devices included in a large Italian registry.