Contribution of Soft Tissue Passive Forces in Thumb Carpometacarpal Joint Distraction.

Thumb carpometacarpal joint space changes when the surrounding soft tissues including the capsule, ligaments, and tendons are stretched or pulled away. When at rest, joint forces originate from passive contraction of muscles and the involvement of joint capsule and ligaments. Previous biomechanical models of hand and finger joints have mostly focused on the assessment of joint properties when muscles were active. This study aims to present an experimental-numerical biomechanical model of thumb carpometacarpal joint to explore the contribution of tendons, ligaments, and other soft tissues in the passive forces during distraction. Five fresh cadaveric specimens were tested using a distractor device to measure the applied forces upon gradual distraction of the intact joint. The subsequent step involved inserting a minuscule sensor into the joint capsule through a small incision, while preserving the integrity of tendons and ligaments, in order to accurately measure the fundamental intra-articular forces. A numerical model was also used to calculate the passive forces of tendons and ligaments. Before the separation of bones, the forces exerted by tendons and ligaments were relatively small compared to the capsule force, which accounted for approximately 92% of the total applied force. Contribution of tendons and ligaments, however, increased by further distraction. The passive force contribution by tendons at 2-mm distraction was determined less than 11%, whereas it reached up to 74% for the ligaments. The present study demonstrated that the ligament-capsule complex plays significant contribution in passive forces of thumb carpometacarpal joint during distraction.

A new magnetic internal distractor: cadaveric study of changes in trapeziometacarpal joint forces.

Distraction is a new treatment for trapeziometacarpal joint osteoarthritis. The purpose of this study was to test the efficiency of magnetic distraction using a new internal distractor in cadavers. The distractor consists of two magnets embedded inside titanium capsules that are implanted on either side of the trapeziometacarpal joint with the same poles facing each other, so that the force between the magnets distracts the joint. Intra-articular forces were recorded pre-implantation, immediately after implantation and again 10 minutes later. We also studied the changes in the forces before and after the procedure in different thumb positions. Our findings show that the trapeziometacarpal joint could be offloaded in all the studied trapeziometacarpal positions.

A case series: Egyptian experience in using chemical pleurodesis as an alternative management in refractory hepatic hydrothorax.

INTRODUCTION: Chemical pleurodesis is an effective treatment for malignant effusion and pneumothorax. Although this mode of therapy is less widely accepted in treatment of patients with hepatic hydrothorax, the need for palliative treatment in such patients encouraged us to do this work. The aim of study was analysing the outcome of chemical pleurodesis using bovoiodine, Vibramycin and talc slurry in treatment of hepatic hydrothorax. MATERIAL AND METHODS: A case series randomized study including 23 patients with symptomatic right side hepatic hydrothorax not responding to medical treatment and repeated thoracocentesis was conducted. From March 2007 to March 2008, 19 men and 4 women with a mean age of 54.3 ±8.1 years (range 42-70 years) underwent medical thoracoscopies to achieve pleurodesis by application of 3 sclerosing agents. RESULTS: Out of the 23 patients pleurodesis was repeated in 20 cases. Three cases did not attend their follow-up so their responses to pleurodesis are not known. The follow-up period of the study was 3 months. The procedure was effective in 15 of 20 patients (75%): 7/8 cases treated with bovoiodine (87.5%), and 4/6 cases with Vibramycin and talc slurry (66.7%) for each. There were 4 recurrences (20%) and a single case of mortality (5%) due to hepatic coma which can be attributed to the course of the disease. We detected minimal morbidity during the follow-up period of 3 months. CONCLUSIONS: The procedure appears to be indicated for these fragile patients especially when medical therapy fails. Chemical pleurodesis deserves to be considered as an alterative therapy in such patients.