N. Wachter

Klinikum Stuttgart · Department of Handsurgery, Plastic Surgery and Microsurgery

Ulnar nerve injuries can cause deficient hand movement patterns. Their assessment is important for diagnosis and rehabilitation in hand surgery cases. The purpose of this study was to quantify the changes in temporal coordination of the finger joints during different power grips with an ulnar nerve block by means of a sensor glove. In 21 healthy su...

In the assessment of hand and upper limb function, detecting sincerity of effort (SOE) for grip strength is of major importance to identifying feigned loss of strength. Measuring maximal grip strength with a dynamometer is very common, often combined with calculating the coefficient of variation (CV), a measure of the variation over the three grip...

Hintergrund/Ziel: Die endoprothetische Versorgung gehört zu den etablierten Verfahren zur Behandlung der schmerzhaften Fingermittelgelenksarthrose. In unserem Haus wurden zwischen 1996 und 1999 bei 16 Patienten 19 DIGITOS-Fingermittelgelenkprothesen implantiert. Es handelt sich um eine scharniergeführte Prothese mit Kolbenmechanismus. Bereits 2007...

Background: Wrist fusion is still a common treatment for patients with advanced stage arthritis. Since patients are often intimidated by the functional limitations, we intended to evaluate the influence of the lack of wrist motion in different positions on the dynamic grip function and the grip strength of the hand. Methods: We simulated wrist fusi...

The purpose of this study was to assess whether there is a universal pattern of movement of the finger joints while performing a cylinder grip. A sensor glove was used to record the finger joint motion of 48 participants. Our observations showed that when examining the fingers, flexion motion began either at the metacarpophalangeal (MP) or proximal...

The purpose of this study was to analyse motion patterns of the finger joints dynamically while making a fist. 10 subjects were examined using the TUB-sensor glove, which was equipped with 14 joint angle sensors. The median time it takes the finger joints to complete flexion until reaching the state of a closed fist ranges between 0.5 to 1.0 s. A s...

The present study analyses force distribution patterns during primary grips. 10 subjects were examined using the TUB-sensor glove, which was equipped with 10 pressure sensors. 5 proximal sensors at the MCP joints and 5 distal sensors at the DIP joints were attached palmarly. 9 different gripping motions were examined: the cylinder grip using 4 diff...

To determine whether the grip of a healthy subject's hand shows certain universal characteristics. To accomplish this, we examined the complex interactions of the fingers during gripping of different-size cylindrical objects. A total of 48 subjects (11 women, 37 men) performed 5 cylinder grips with different object sizes. The 14 joint angular profi...

The identification of pathological function of finger movement in nerve palsy is important for clinical diagnostics, rehabilitation and assessment in hand surgery. The goal of the study was to analyze grip pattern changes in simulated ulnar nerve palsy by a sensor glove. In 20 volunteers, the movement patterns of the fingers were assessed by a sens...

This study examined patterns of grip strength when maximal and submaximal effort are applied. Using a sensor glove, 50 healthy subjects performed two different power grips. Both maximal and submaximal gripping showed characteristic patterns of strength distribution that were independent of the degree of power applied. Significant differences were a...

Most important methods for the surgical treatment of painful arthritis of the proximal interphalangeal joint are the joint fusion or the implantation of a prosthesis. There are a lot of different models for joint replacement. Sixteen patients received 19 middle joint replacements performed with the DIGITOS-prosthesis between 1996 and 1999. Over a p...

Hintergrund: Bei Handverletzungen besteht ein Interesse, möglichst frühzeitig anhand des Verletzungsmusters die voraussichtliche Dauer der Arbeitsunfähigkeit einzuschätzen. Existierende Bewertungsschemata wie z. B. der HISS-Score (Hand Injury Severity Scoring System) sind komplex und aufwändig zu bestimmen. Material und Methoden: Basierend auf bei...

Zur Behandlung der Panarthrose des Handgelenks stehen die Denervation, der Gelenkersatz und die Arthrodese zur Verfügung. Vor dem Hintergrund des zunehmend angewandten prothetischen Gelenkersatzes soll der Stellenwert der Handgelenksarthrodese erörtert werden. Bei 32 Patienten wurde wegen einer schmerzhaften Panarthrose eine Handgelenksarthrodese d...

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...

Studienziel: Ziel der Studie war zum einen die Entwicklung eines neuen Scores zur Risikoabschätzung einer heterotopen Ossifikation (HO) nach Hüft-TEP, andererseits die Darstellung unserer Ergebnisse nach kombinierter Therapie der HO (chirurgische Resektion, Radiatio und medikamentöse Therapie). Methode: Von 1990 bis 2003 wurden 50 Patienten die weg...

Background: Primary total hip arthroplasty (THA) has been suggested for old patients with acetabular fractures, because it permits immediate full weight bearing and precludes secondary surgery for posttraumatic osteoarthritis. Patients and Methods: The authors retrospectively analyze the outcome after 35 primary THAs performed between 1982 and 2001...

Stainless steel and commercially pure titanium are widely used materials in orthopedic implants. However, it is still being controversially discussed whether there are significant differences in tissue reaction and metallic release, which should result in a recommendation for preferred use in clinical practice. A comparative study was performed usi...

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...

To test mechanical bone quality and bone mineral density of the femoral head at the day of implantation as indicators for femoral prosthesis loosening. Mechanical bone quality of a femoral head slice was assessed by destructive compression testing combined with bone mineral density measurements using peripheral quantitative computed tomography. Fou...

Femoral head-preserving treatment for femoral neck fractures with cancellous screws is a method widely performed, but its success depends on the quality of primary reduction. The goal of our study was to evaluate the relevance of reduction quality on the clinical outcome. We retrospectively analyzed the postoperative reduction result of 39 patients...

A bone defect of 14 cm resulted after wrist implant removal because of loosening in a 46-year-old patient. Performing wrist arthrodesis the defect was reconstructed by a vascularized fibular transfer. Solid bone fusion was complete in six weeks. Free function of the digits was seen because of length reconstruction.

Nach Explantation einer gelockerten Handgelenkprothese bei einem 46-jährigen Patienten resultierte ein langstreckiger knöcherner Defekt des Handgelenks.Dieser Defekt wurde im Rahmen einer Arthrodese mit einem freien Fibulatransplantat überbrückt. Die knöcherne Fusion dauerte 6 Wochen und durch den Längenausgleich konnte eine freie Fingerfunktion er...

The appearance of animal bite injuries varies in regard to location and extent. Injuries with puncture wounds involving the extremities carry great risk of infection. Managing the complications often requires substantial medical treatment and increased costs. The aim of this study is the evaluation of the course of disease, medical care, and treatm...

The aim of this study was to evaluate the influence of microstructural parameters, such as porosity and osteon dimensions, on strength. Therefore, the predictive value of bone mineral density (BMD) measured by quantitative computed tomography (QCT) for intracortical porosity and other microstructural parameters, as well as for strength of cortical...

Background: Major osseous defects in trauma or tumor patients require surgical reconstruction. While transplantation of autogenous or allogenous bone is still regarded as the standard, a multitude of alternative substitute materials has been developed in the recent years. Currently, the majority of commercially available products is based on calciu...

The appearance of animal bite injuries varies in regard to location and extent. Injuries with puncture wounds involving the extremities carry great risk of infection. Managing the complications often requires substantial medical treatment and increased costs. The aim of this study is the evaluation of the course of disease, medical care, and treatm...

Background: Patients with acetabular fractures frequently develop osteoarthritis, femoral head osteonecrosis, or heterotopic ossification. Secondary total hip arthroplasty (THA) seems a possible salvage procedure, but little is known about its long-term outcome in these individuals. Patients and Methods: At our institution, 37 patients aged 20-74 y...

Covering tertiary soft-tissue injuries on the ankle joint and on the calcaneal part of the foot has so far been the domain for free flap use. With the distally based neurocutaneous sural artery flap (sural flap) and the distally based lateral supramalleolar flap, there are now fasciocutaneous island flaps available which allow quick covering of inj...

The anterior cruciate ligament (ACL) rupture is among the most frequent injuries of the joints. Actually, there is no doubt regarding the necessity for surgical treatment. However, little is known about the progression of osteochondral damages and their distribution following reconstruction of the ACL. We treated 150 tears of the ACL either acute (...

The anterior cruciate ligament (ACL) rupture is among the most frequent injuries of the joints. Actually, there is no doubt regarding the necessity for surgical treatment. However, little is known about the progression of osteochondral damages and their distribution following reconstruction of the ACL. We treated 150 tears of the ACL either acute (...

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 (coll...

Calcium phosphates are frequently used as bone substitute materials because of their similarity to the mineral phase of bone, absence of antigenicity, and excellent osteoconductivity. However, in most currently available mineral substitutes, resorption occurs slowly if at all. In contrast, calcium phosphate cements have shown rapid resorption and r...

Hand fractures are common injuries in infants. Complications are rare because of potent remodeling dimension and rapid healing of growing bone. There is limited remodeling capacity for angular and rotational deformity so displaced fractures often require open reduction and internal fixation. The authors present a splint system for a protected reduc...

Ziel der Arbeit ist der Vergleich der klinischen und radiologischen Ergebnisse zweier verschiedener Methoden der Rhizarthrosebehandlung. Achtzehn Patienten wurden wegen 20 schmerzhafter Daumensattelgelenkarthrosen operativ versorgt. Elfmal wurde eine Resektions-Suspensions-Arthroplastik nach Epping (Kollektiv I) und neunmal eine alleinige Trapezekt...

The essential problematic of the distal fracture of the radius lies in the quality of its reduction and retention. 35 patients with distal fractures of the radius and strain fractures of the styloid process of the ulna were followed up with regard to their functional and radiological results and their subjective symptoms. Patients with intra-articu...

The aim of this study was to evaluate the predictive value of bone mineral density and intracortical porosity measured by microcomputed tomography for the strength of cortical bone biopsies. Experimental study comparing the predictive value of bone mineral density and of intracortical porosity determined in vitro by microcomputed tomography for the...

The purpose of this study was to assess the predictive value of the Singh index as well as quantitative computed tomography for the in vitro local mechanical competence of the cancellous bone of the proximal femur. An experimental study examining the relation between mechanical properties and bone mineral density of the femoral neck determined in v...

The essential problematic of the distal fracture of the radius lies in the quality of its reduction and retention. 35 patients with distal fractures of the radius and strain fractures of the styloid process of the ulna were followed up with regard to their functional and radiological results and their subjective symptoms. Patients with intra-articu...

The high importance of intracortical porosity for mechanical strength of cortical bone has been established. The contribution of other parameters of microstructure such as osteon dimensions for strength is in discussion. The aim of this study was to evaluate the predictive value of microcomputed tomography (mCT) for porosity and other microstructur...

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 a...

Peripheral quantitative computed tomography (pQCT) is an established diagnostic method for assessment of bone mineral density in the diagnosis of osteoporosis. However, the capacity of structural parameters of cancellous bone measured by high-resolution computed tomography remains to be explored. In 33 patients, bone mineral density (BMD) of the pr...

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 pr...

In a prospective randomized clinical trial, ADCON-T/N was investigated with regard to its effectiveness in fresh traumatic injuries of the flexor tendons in Zone II of the hand. Thirty patients participated in the trial. Following a standardized technique of tendon repair, the total active motion (TAM) and total extension lag (TEL) were determined...

The high importance of intracortical porosity for mechanical strength of cortical bone has been established. The contribution of other parameters of microstructure such as osteon dimensions for strength is in discussion. The aim of this study was to evaluate the predictive value of microcomputed tomography (µCT) for porosity and other microstructur...

Calcium phosphates are frequently used as bone substitute materials because of their similarity to the mineral phase of bone, absence of antigenicity, and excellent osteoconductivity. However, in most currently available mineral substitutes, resorption occurs slowly if at all. In contrast, calcium phosphate cements have shown rapid resorption and r...

Griffkraftmessungen mit Dynamometern sind abhängig von der Mitarbeit und der Motivation des Untersuchten. Das Erkennen eines vorgetäuschten Kraftverlustes ist ein bislang ungelöstes Problem. Mit einem an der Technischen Universität Berlin entwickelten Sensorhandschuh können über zehn Drucksensoren die Kraftverteilungsmuster bei beliebigen Griffen e...

Die Messung der Gelenkwinkel wird mit Winkelmessern nach der Neutral-Null-Methode vorgenommen. Diese Messungen sind untersucherabhängig und unterliegen dadurch großen Schwankungen. Ein neuentwickelter Sensorhandschuh ermöglicht die computergestützte Erfassung der Greifmuster der Hand. In einer vergleichenden Studie wurden die Fingergelenkwinkel an...

Calcium phosphates are frequently used as bone substitute materials because of their similarity to the mineral phase of bone, absence of antigenicity, and excellent osteocon-ductivity. However, in most currently available mineral substitutes, resorption occurs slowly if at all. In contrast, calcium phosphate cements have shown rapid resorption and...

The reconstruction of soft-tissue damage on the part of the head which is covered with hair is aimed not only at repairing the damage in such a way that it will withstand mechanical strain but also at the restoring the hair on the scalp. In a 5-year-old boy with a scalping injury involving second- and third-degree soft-tissue damage over an area of...

Zusammenfassung Die Rekonstruktion von Weichteilschäden am behaarten Kopf zielt neben einer mechanisch belastbaren Defektdeckung auf die Wiederherstellung der Kopfhautbehaarung ab. Bei einem 5-jährigen Jungen mit einer Skalpierungsverletzung mit teils zweit-, teils drittgradigem Weichteilschaden nach Hundebiss mit einer Ausdehnung von 20-mal 12 cm...

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...

Secondary haematogenous joint involvement is seen in less than 1% of patients with Salmonella infections. These atypical infections are frequently encouraged by pre-existing local or systemic disease. We present a case of a patient with known alcohol abuse who developed a septic infection of her right hip requiring resection of the femoral head. Hi...

Objective: The purpose of this study was to assess the validity of two methodically different radiological parameters, bone mineral density and Singh Index, for the prediction of mechanical properties in femoral cancellous bone. Design: Coherence between in vitro evaluation of mechanical properties and bone mineral density on a femoral bone slic...

Sekundäre hämatogene Gelenkinfektionen werden bei weniger als 1 % aller systemischen Salmonellosen beobachtet. Lokale Gewebeschädigungen oder systemische Grunderkrankungen begünstigen das Zustandekommen dieser atypischen Infektionen. Wir stellen den Fall einer alkoholabhängigen Patientin dar, bei welcher eine Salmonellenkoxitis auf dem Boden einer...