The deformation of a beam lattice is investigated as a two‐dimensional model of a foam. Forces, moments, displacements and rotations are averaged leading to stress, couple stress, strain and ...curvature on the macroscale. Therefore, the effective medium is assumed to be micropolar.
The estimation of the time off work depending on the injury pattern and severity is of major interest in the treatment of hand injuries. The predictive value of the HISS score (Hand Injury Severity ...Scoring System) was evaluated.
According to this score, 184 work-related injuries (1999 to 2002) were analyzed prospectively, excluding injuries of both hands. The median age was 37.9 years (18 to 65 years), 11 % of the patients were female.
A significant correlation was established between the HISS score and the time off work (p < 0.0001, r = 0.51). The score also correlated with the degree of work incapacity (p < 0.0001).
Our data confirm the predictive value of the HISS score for the early estimation of the time off work resulting from hand injuries. However, the estimation is limited to injuries distal to the wrist.
In contrast to the standard therapy of flexor tendon injuries in adults, the postoperative treatment program for children remains a controversial topic. Some prefer immobilization therapy in a ...variety of forms and for different periods of time. Others prefer early mobilization programs. We present results for twenty-eight children with thirty-seven flexor tendon injuries. The average age was 5.8 years. After primary tendon suture in children six years and younger (group A), our postoperative program consisted of immobilization for three weeks. The older children (group B) were treated with an early passive mobilization program. Follow-up examinations were carried out on twenty six of the children at three months and at 3.7 years. Three months after surgery, the children in group A showed only average results while those in group B presented good finger motion. After 3.7 years both groups showed good results.
In dynamic and static scapholunate instability after trauma, the repair of the scapholunate ligament is important to avoid scapholunate advanced collapse of the wrist. Direct suture even of ...fresh-torn ligaments can be technically demanding and occasionally unreliable, thus reconstruction may require additional tissue beside the ligament. Eighteen patients suffering from dynamic (n = 10) and static (n = 8) scapholunate instability were treated by a dorsal ligament reconstruction six months after trauma. A clinical wrist score according to Cooney showed an average of 86 points (maximum 100) within a follow-up of nineteen months after surgery. X-ray films documented no significant loss of scapholunate reduction. Using local tissue only, this method is always possible, very reliable and easy to perform.
Objective of this study is to compare clinical and radiological results of two different methods of treatment for trapeziometacarpal osteoarthrosis of the thumb. Eighteen patients received operative ...treatment. An operation according to Epping was performed in eleven cases (collective I), while nine cases were treated with a trapeziectomy only (collective II). The mean follow-up of the first collective was 40 months and 15 months for the second one. The results of the two patient groups were subjected to statistical comparison in a retrospective study. This revealed no significant differences with regard to active range of motion, power, and subjective symptoms, classified according to the Buck-Gramcko score. With a mean of 49 points for the first and 50 points for the second collective, both achieved very good results. However, the mean operating time was significantly shorter in the patients treated with a trapeziectomy only, while the mean distance between the base of the first metacarpal bone and the scaphoid bone was significantly greater in this group. This is surely due to the shorter follow-up of the patients who underwent trapeziectomy only, since further proximalisation has to be expected. We were able to demonstrate that both methods yield equally good results, and hence the simpler technique of trapeziectomy alone should be given preference, at least in the standard situation of a patient, whose intermetacarpal ligaments offer sufficient stability after trapeziectomy.
Joint angles are measured using goniometers according to the neutral-zero method. These measurements are dependent on the examiner and are thus subject to great variation. With a newly developed ...sensor glove, the grip patterns of the hand can be captured with a computer-assisted technique. In a comparative study involving five subjects, the joint angles during power grip around a cylindrical body and while clenching a fist were determined by nine examiners at three different times, using the conventional technique according to the neutral-zero method. In the same experimental design, the joint angles were measured with the sensor glove. As a criterion for the reproducibility of the measurements, the intraclass correlation coefficient (ICC) was calculated by means of an analysis of variance. The ICC is a value which approximates 1 if the reliability of the measurements is high. At 0.94, the ICC of the data determined with the sensor glove was markedly higher than the mean ICC for all examiners of 0.50 using the conventional method. Besides the measurement of the finger joint angles, the sensor glove allows the dynamic recording of joint movements of all finger joints during different grip patterns of the hand.
Grip strength measurements with the aid of dynamometers are dependent on the cooperation and motivation of the individual examined. Recognising a simulated loss of grip is a hitherto unresolved ...problem. With a sensor glove developed at the Berlin University of Technology, the force distribution pattern of any form of grip can be captured via ten pressure sensors and evaluated by computer. In five subjects, the force distribution patterns at submaximum and maximum force of five different grips were determined in three successive measurements each. The data were recorded in force-time diagrams. For each act of grasping, the measurements produced a curve with near-constant measuring signals within a defined period (plateau). The difference in the plateau heights of successive grips and the structures of the individual plateaux (oscillation, standard deviation) were used as distinguishing criteria. The dynamics of the measuring signals showed statistically significant differences between grips with submaximum and maximum force (p < 0.0001).
The treatment of osteoarthrosis of the proximal interphalangeal joint by prosthesis bears several specific problems. With the DIGITOS-prosthesis a new implant is now available. It is a cemented ...modular hinged prosthesis. We report our experiences with this implant from a prospective clinical trial. Seven patients with osteoarthrosis of the proximal interphalangeal joint had ten prosthetic middle joint replacements performed with DIGITOS-prostheses. Over an observation period of two years, the functional results were found to be good. The mean preoperative range of motion in the affected joints was 51.5 degrees. Three months after surgery, this had improved to 60.5 degrees, but then decreased to 53.0 degrees after one year and to 49.5 degrees, i.e. the original range of motion, by the end of the second postoperative year. No implant became loose. Nearly all patients were free from pain. The only serious complication was an iatrogenic lesion of the middle slip of the extensor aponeurosis resulting in a buttonhole deformity. In spite of these encouraging two-year results, the further follow-up has to be observed carefully.