ABSTRACT
BACKGROUND: This study was designed to measure transverse forces between the 1st and 2nd metatarsals after reducing the intermetatarsal angle (IMA) in normal and hallux valgus (HV) feet, during non weight-bearing and weight-bearing phases of gait. METHODS: Four cadaver feet, three normal and one with hallux valgus, were used. A new suture button device (CyclaPlex™) composed of screw-type buttons connected with a wire was implanted at the mid-shaft of the 1st and 2nd metatarsals of all the feet. IMA was reduced using a tensioning device to pull the wire which was secured laterally at the 1st metatarsal. The 1st metatarsal was pulled laterally towards the 2nd metatarsal until an IMA of about 6° was achieved. The amount of force applied at this point was registered on the force indicator. Each foot attached to the tensioning device was placed in a special construct loaded with weights equal to the original body weight of the donor and positioned at 15° tilt (simulating propulsion phase of the gait cycle). The intermetatarsal force under load indicated on the tensioning device was recorded. RESULTS: The average recorded transverse intermetatarsal force was 28.5 N (SD 4.2 N) during non weight-bearing phase; the mean increase in the measured force at weight-bearing and 15° tilt was 6 N (SD 2.6 N). CONCLUSIONS: We measured the transverse forces between the 1st and 2nd metatarsals with the use of a suture button device (CyclaPlex™). The data obtained from the measurements will provide a better understanding of foot biomechanics and may therefore also facilitate the development of new devices designed to decrease IMA in HV surgery.
Subject(s)
Hallux Valgus/physiopathology , Metatarsal Bones/physiopathology , Aged , Aged, 80 and over , Bone Wires , Cadaver , Female , Hallux Valgus/diagnostic imaging , Hallux Valgus/surgery , Humans , Male , Metatarsal Bones/diagnostic imaging , Metatarsal Bones/surgery , Osteotomy/methods , Radiography , Stress, Mechanical , Suture Techniques , Sutures , Weight-Bearing/physiologyABSTRACT
Sterile elastic exsanguination tourniquets (HemaClear; OHK Medical Devices, Haifa, Israel) are relatively new on the market but are widely used because of the ease and speed of their application. The sterile elastic exsanguination tourniquet consists of a silicon ring wrapped in a stockinet sleeve with pull straps. The physician places the ring on the patient's fingers or toes and then pulls the straps proximally. The silicon ring rolls up the limb, and the stockinet sleeve unrolls onto the limb. During proximal rolling, the device displaces blood out of the limb (exsanguination). When the elastic ring reaches the preferred occlusion location, the pulling motion is stopped. The ring exerts suprasystolic pressure on the limb, thereby blocking arterial blood flow into the limb and thus acts as a tourniquet. HemaClear tourniquets are thin and sterile and therefore provide a large operative field. The authors report 2 cases of pulmonary embolism after HemaClear tourniquet application in patients with traumatic injuries (fractures of the patella and tibial plateau). Exsanguination applies mechanical stress that might dislodge a preexisting deep venous thrombosis, leading to the serious complication of pulmonary embolism. The authors want to increase awareness of this possible fatal complication during procedures performed on the lower limbs, when the HemaClear tourniquet is used for exsanguination of the affected limb. Careful consideration should be given to the use of HemaClear tourniquets in high-risk patients and those with traumatic injuries, especially when there has been a delay in surgery.
