Change in the temporal coordination of the finger joints with ulnar nerve block during different power grips analyzed with a sensor glove

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 subjects, the onset and end of the active flexion of the 14 finger joints when gripping objects of different diameters was recorded by a sensor glove. The measurement was repeated after an ulnar nerve block was applied in a standardized setting. The change in the temporal coordination of the metacarpophalangeal (MCP), proximal interphalangeal (PIP) and distal interphalangeal (DIP) joints with and without the nerve block was calculated within the same subject. In healthy subjects, the MCP joints started their movement prior to the PIP joints in the middle and ring finger, whereas this occurred in the reverse order at the index and little finger. The DIP joint onset was significantly delayed (P<0.01). With the ulnar nerve block, this coordination shifted towards simultaneous onset of all joints, independent of the grip diameter. The thumb and index finger were affected the least. With an ulnar nerve block, the PIP joints completed their movement prior to the MCP joints when gripping small objects (G1 and G2), whereas the order was reversed with larger objects (G3 and G4). The alterations with ulnar nerve block affected mainly the little finger when gripping small objects. With larger diameter objects, all fingers had a significant delay at the end of the PIP joint movement relative to the MCP and DIP joints, and the PIP and DIP joint sequence was reversed (P<0.01). Based on the significant changes in temporal coordination of finger flexion during different power grips, there are biomechanical effects of loss of function of the intrinsic muscles caused by an ulnar nerve block on the fine motor skills of the hand. This can be important for the diagnosis and rehabilitation of ulnar nerve lesions of the hand.

[Diagnostic ability of power measurement of different grip forms for distal median nerve lesion]

BACKGROUND

Peripheral lesions of the median nerve cause characteristic changes of the grip function of the hand. For evaluating grip force changes, measurement by dynamometers (JAMAR dynamometer and pinch dynamometer) is of high relevance. In this study the ability of grip force measurements of different grip forms was evaluated to discriminate between a simulated median nerve lesion and healthy subjects.

MATERIAL AND METHODS

In 21 healthy subjects, the grip force of power grip was measured by the JAMAR dynamometer at the second stage including measurement of force at the fingertips and the thenar by a sensor glove. With a pinch dynamometer the power of palmar abduction, precision grip, pincer grip and pinch grip was determined. Measurements were performed with and without median nerve block at the wrist.

RESULTS

In power grip of the JAMAR dynamometer at the second stage a significant reduction of the grip force of 13.4% was found (p < 0.03). The power distribution between the fingers D2-D5 did not change with median nerve block. The most relevant reduction of grip force in median nerve block compared with the healthy control was measured in palmar abduction (72.1%, p < 0.0002), followed by precision grip 31.0% (p < 0.0001), pincer grip 23.6% (p < 0.0004) and pinch grip 18.8% (p < 0.0002).

CONCLUSIONS

For the discrimination between healthy subjects and subjects with a median nerve block there was a limited relevance of the measurement of the power grip and force distribution at the fingers by the JAMAR dynamometer. However, the best distinction was observed by dynamometric measurement of other grips than power grip, such as palmar abduction, precision grip, pincer grip and pinch grip. The results could be relevant for the clinical diagnostics and rehabilitation of median nerve lesion, complementing the widespread measurement of the power grip by other grip forms.

[Linked Prosthesis for the Proximal Interphalangeal Joint: 17-Year Long-Term Results]

BACKGROUND/PURPOSE

Joint replacement is a widely used procedure to treat painful osteoarthritis of the proximal interphalangeal joint. From 1996 to 1999, 16 patients received 19 hinged, piston-based DIGITOS prostheses in our department. In 2007, the 7-year clinical course of 14 patients (17 devices) was published in this journal. Now 12 of these patients (15 devices) have been followed with an average history of 17 years, and the preoperative data has been compared with the results after 7 and 17 years, respectively.

PATIENTS AND METHODS

The patients were 10 women and 2 men, whose average age at the time of the preoperative examination was 63 (48-69) years. Replacements were performed on the index (6), middle (6), and ring finger (3). There were 14 idiopathic osteoarthritic changes and 1 posttraumatic osteoarthritic change. Follow-up included a clinical (range of motion in the proximal interphalangeal joint, extension lag, pain) and radiological examination. In addition, the DASH score was obtained and the patients were asked whether or not they would undergo the same surgery again. The results after 7 and 17 years were reviewed for statistically significant differences.

RESULTS

While there were significant changes regarding extension lag and flexion in the first 7 years after replacement of the proximal interphalangeal joint, only minor changes were observed between 7 and 17 years after surgery. While the prosthesis was in its correct position in the first 2 years after implantation, all prostheses exhibited radiolucent lines after 4 years and periprosthetic osteophytes after 5 years. 17 years after surgery, the radiolucent lines had not increased at all and the osteophytes had increased insignificantly compared with the 7-year findings. None of the patients reported pain; all of them said that they would undergo the same surgical procedure again.

CONCLUSION

While there were significant clinical and radiological changes in the first 7 years after replacement of the proximal interphalangeal joint by a linked DIGITOS prosthesis, only minor changes were observed between 7 and 17 years after surgery.

[Simulated Total Wrist Fusion and its Influence on Hand Grip Function]

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 fusion in 20° extension and 20° flexion and evaluated the following grip types: fist closure, 2 different power grips, pinch grip and precision grip. A TUB sensor glove was used, which allowed us to dynamically record the range of motion (ROM) of the finger joints as well as grip strength. Nineteen healthy subjects participated and all types of grips were performed using a standardised protocol with and without simulated wrist fusion.

RESULTS

Lack of wrist motion in 20° extension had no relevant effect on the fingers' ROM, grip speed or strength. Simulated fusion in 20° flexion also had no influence on ROM or grip speed, rejecting our hypothesis that a tenodesis effect of the extensors in flexion would decrease ROM in the finger joints and grip speed. However, we were able to show a significant decrease of grip strength in flexion compared with extension or healthy wrists. The decrease averaged between 23 and 42% of healthy values, depending on the grip type. There was no change in strength distribution among the fingers.

CONCLUSION

We didn't find any impact of lack of wrist motion on finger movement during forceful hand grip at normal speed. However, a significant loss of grip strength in flexed position of the wrist joint should be considered in patients with an indication for bilateral wrist fusion.

[MRI in musculoskeletal imaging: possibilities and limitations]

Muscle injuries are the most frequent sport injuries in athletes. In addition to a thorough clinical examination and the history of the trauma mechanism, imaging modalities are required to correctly classify the injury and plan the future treatment and rehabilitation. The two major modalities are ultrasound and magnet resonance imaging (MRI). This article aims to give a comprehensive overview on the possibilities and limitations of MRI imaging in musculoskeletal injuries as well as insight into current development, classifications and technologies.

[Midterm results following denervation of the ankle]

BACKGROUND

Complications related to arthrodesis of the ankle or total ankle replacement require a critical assessment of the indication. Using denervation of the ankle, we have the possibility to delay the above-named surgical treatment for a number of years. The aim of this follow-up study was to review the results of ankle denervation after several years.

METHODS

Within a follow-up examination, we were able to evaluate the results of 45 patients an average of 102 months following ankle denervation.

RESULTS

A total of 82.2% of patients indicated an improvement of pain for an average of 60.9 months; 71.1% of patients reported that the operation was worthwhile. The AOFAS score improved from an average 37.9 (range 26-68) preoperatively to 55.6 (range 24-84) at follow-up.

CONCLUSIONS

Ankle denervation can achieve good ankle pain reduction in the treatment of ankle arthrosis. Denervation should be considered a long-term treatment concept.

Dynamic aspects during the cylinder grip--flexion sequence of the finger joints analyzed using a sensor glove

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 interphalangeal (PIP) joints, with the distal interphalangeal (DIP) joints always last to move (p = 0.0052). The sequence of the joints at the end of the gripping motion was different than at the beginning. Here, the only statistically significant observation was that the DIP joints fully flexed only once the MP joints had flexed fully. Apart from that, it was completely variable which joint reached its final position first or last. The analysis also revealed that synchronization of four identical joints (i.e. the four PIP joints) was significantly higher than synchronization of the 12 finger joints. Although synchronization was already high at the beginning of the flexion motion, it increased significantly by the time the joints completed their movement.

[Early results after palmar multi-axial plate osteosynthesis for treatment of distal radius fractures]

In a prospective study a total of 49 fractures in 47 patients were treated with open reduction and palmar plate osteosynthesis. The results were evaluated radiologically, clinically and with the disability of arm-shoulder-hand (DASH) score. The emphasis was on early postoperative results. The patients consisted of 11 men and 36 women aged 21–85 years old. Very good or good results were achieved in 79.6% of the patients, a fair result in 16.3% and a poor result in 4.1% according to the Lidström criteria. In 65.9% of cases very good or good functional results were achieved, in 22.7% fair and in 11.4% only poor results. The DASH score showed high patient satisfaction in 70.2%, moderate satisfaction in 25.5% and only little satisfaction in 4.3% of patients. Complications occurred in 14.3% of patients and the average duration of sick leave was 45.8 days. Open reduction of distal radius fractures using palmar plates with multi-axial angular stability shows good radiological and functional results even shortly after the operation.

[The dynamics of motion sequences of the finger joints during fist closure]

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 specific pattern can be seen for every finger. The PIP and DIP joints appear to be linked, with the DIP trailing the PIP joint. At the thumb the IP is trailing the MCP joint. The MCP joint shows more variation at the beginning of flexion: while in some cases it initiates movement in a finger, in other cases its flexion falls behind the PIP joint movements. The completion of flexion is achieved by the MCP joints, with the PIP and DIP joints reaching their end of motion first. The range of motion (ROM) at the MCP joints shows a finger-dependent median of 79-97°. At the PIP joints the median lies between 87° and 90°, at the DIP joints between 52° and 68°. At the thumb it is 21° for the MCP and 24° for the IP joint. The linkage between PIP and DIP joints can also be seen when analysing the ROM. The coupling ratio amounts to 0.77 at the index finger, 0.75 at the middle and ring finger and 0.57 at the small finger.

DIGITOS-Fingermittelgelenkprothese - Langzeitergebnisse

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 period of seven years, 14 patients with 17 prostheses have been observed prospectively. In the 7-year follow-up, a minimal radiolucent line at the bone-cement junction and huge periarticular osteophytes could be found in every case. No cortical penetration, luxation, or implant fractures were recorded. The preoperative median range of motion was 50 degrees. Postoperatively, there was an improvement to 60 degrees. The range of motion decreased to 50 degrees after one year and to as little as 30 degrees after seven years. Preoperatively, eleven patients had pain with activity and three had pain without activity. During the whole follow-up period there were only two patients who had pain at work. All patients were satisfied with the results of the operation throughout the control period and would choose the same treatment again.

Einschätzung der Verletzungsschwere sowie der Dauer der Arbeitsunfähigkeit bei Handverletzungen mit dem HISS-Bewertungsschema

BACKGROUND

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.

MATERIAL AND METHODS

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.

RESULTS

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).

CONCLUSION

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.

[Treatment of flexor tendon injuries in children]

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.

[Measuring grip strength of the hand with a sensor glove by gripping with submaximal and maximal strength]

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).