Case Report: Description of two fractures during the use of a powered exoskeleton.

Introduction: Powered robotic exoskeletons are a promising solution to enable standing and walking in patients with spinal cord injury (SCI). Although training and walking with an exoskeleton in motor complete SCI patients is considered safe, the risks of unexpected (technical) adverse events and the risk of fractures are not fully understood. This article reports the occurrence of two different cases of bone fracture during exoskeleton usage. Furthermore, advice is given for extra safety training and instructions. Case presentation: The first case concerns a 47-year-old woman with T12 AIS A SCI. Her exoskeleton shut down unexpectedly probably causing a misalignment of the joints of her lower extremities relative to the joints of the exoskeleton, which resulted in a fracture of her left tibia. The second case involves a 39-year-old man with L1 AIS B SCI. An unexpected fracture of the right distal tibia occurred without a specific prior (traumatic) incident. Discussion: Exoskeleton training instructors, SCI patients and their buddies should be instructed how to handle emergency situations. Furthermore, they should be aware of the risk of stress fractures of the lower extremities. Proper alignment of the exoskeleton relative to the body is of utmost importance to reduce fracture risk. In the case of swelling and discoloring of the skin, radiographic examination should be performed in order to exclude any fracture.

Operative treatment algorithm for foot deformities in Charcot-Marie-Tooth disease.

The present article presents a short summary concerning the pathomechanisms and clinical presentation of foot deformities in Charcot-Marie-Tooth syndrome. Furthermore, a classification system is introduced and based on a recently performed review of the literature an operative treatment algorithm is provided. The operative technique of the following surgical procedures is described in more detail: 1. dorsiflexion osteotomy at the base of the 1st metatarsus, 2. dorsiflexion osteotomy at the base of a lesser metatarsal bone, 3. claw hallux correction including fusion of the first phalangeal joint, 4. claw toe correction, 5. transfer of extensor digitorum longus tendons to the peroneal tendons and finally 6. tibialis posterior tendon transfer to the dorsiflexors of the foot.

Simple resection arthroplasty for treatment of 4th and 5th tarsometatarsal joint problems. A technical tip and a small case series.

Osteoarthritis, primary or secondary, of the fourth and/or fifth tarsometatarsal (TMT) joint is a rare condition. When conservative treatment fails or proves to be unacceptable for the patient, operative treatment is an option. In this article the technique of resection arthroplasty is described and a retrospective case series of 6 patients is presented. Three patients underwent tendon interposition arthroplasty after resection of the two joints and in the last three cases no interposition at all was performed. Results suggest that resection arthroplasty without interposition may be as effective as other operative treatment options for patients with fourth and fifth TMT pathology.

Foot lengthening and shortening during gait: a parameter to investigate foot function?

INTRODUCTION: Based on the windlass mechanism theory of Hicks, the medial longitudinal arch (MLA) flattens during weight bearing. Simultaneously, foot lengthening is expected. However, changes in foot length during gait and the influence of walking speed has not been investigated yet. METHODS: The foot length and MLA angle of 34 healthy subjects (18 males, 16 females) at 3 velocities (preferred, low (preferred -0.4 m/s) and fast (preferred +0.4 m/s) speed were investigated with a 3D motion analysis system (VICON(®)). The MLA angle was calculated as the angle between the second metatarsal head, the navicular tuberculum and the heel in the local sagittal plane. Foot length was calculated as the distance between the marker at the heel and the 2nd metatarsal head. A General Linear Model for repeated measures was used to indicate significant differences in MLA angle and foot length between different walking speeds. RESULTS: The foot lengthened during the weight acceptance phase of gait and shortened during propulsion. With increased walking speed, the foot elongated less after heel strike and shortened more during push off. The MLA angle and foot length curve were similar, except between 50% and 80% of the stance phase in which the MLA increases whereas the foot length showed a slight decrease. CONCLUSION: Foot length seems to represent the Hicks mechanism in the foot and the ability of the foot to bear weight. At higher speeds, the foot becomes relatively stiffer, presumably to act as a lever arm to provide extra propulsion.

Classification of forefoot pain based on plantar pressure measurements.

BACKGROUND: Plantar pressure is widely used to evaluate foot complaints. However, most plantar pressure studies focus on the symptomatic foot with foot deformities. The purposes of this study were to investigate subjects without clear foot deformities and to identify differences in plantar pressure pattern between subjects with and without forefoot pain. The second aim was to discriminate between subjects with and without forefoot pain based on plantar pressure measurements using neural networks. METHODS: In total, 297 subjects without foot deformities of whom almost 50% had forefoot pain walked barefoot over a pressure plate. Foot complaints and subject characteristics were assessed with a questionnaire and a clinical evaluation. Plantar pressure was analyzed using a recently developed method, which produced pressure images of the time integral, peak pressure, mean pressure, time of activation and deactivation, and total contact time per pixel. After pre-processing the pressure images with principal component analysis, a forward selection procedure with neural networks was used to classify forefoot pain. FINDINGS: The pressure-time integral and mean pressure were significantly larger under the metatarsals II and III for subjects with forefoot pain. A neural network with 14 input parameters correctly classified forefoot pain in 70.4% of the test feet. INTERPRETATION: The differences in plantar pressure parameters between subjects with and without forefoot pain were small. The reasonable performance of forefoot pain classification by neural networks suggests that forefoot pain is related more to the distribution of the pressure under the foot than to the absolute values of the pressure at fixed locations.

Quantitative ultrasound of lower leg and foot muscles: feasibility and reference values.

BACKGROUND: Ultrasound is a non-invasive method to quantitatively measure various muscle parameters. Purpose of this study was to assess the feasibility of ultrasound of lower leg and foot muscles and to obtain reference values for muscle thickness (MT) and echo intensity (EI). METHODS: Ultrasound measurements of leg and foot muscles were performed in 60 healthy adults. MT and EI were quantitatively determined for the abductor hallucis (AH), extensor digitorum brevis (EDB), extensor hallucis longus (EHL) and peroneus longus (PER) muscles. Influence of age, height, weight and sex was determined using a multiple linear regression analysis. RESULTS: All muscles except the AH could easily be visualized with ultrasound. EI tended to be increased above 60 years and MT was significantly higher in men compared to women, necessitating age- and sex-dependent reference values. CONCLUSIONS: This study shows that muscle ultrasound is capable of visualizing lower leg and foot muscles and reference values for MT and EI can be obtained. Future research will focus on the use of these reference values to evaluate muscle abnormalities caused by neuromuscular disorders like hereditary motor and sensory neuropathy.

Flexible cavovarus feet in Charcot-Marie-Tooth disease treated with first ray proximal dorsiflexion osteotomy combined with soft tissue surgery: a short-term to mid-term outcome study.

OBJECTIVES: The purpose of this paper was to retrospectively evaluate the short-term to mid-term results of combined first ray proximal dorsiflexion osteotomy and soft tissue surgery in treatment of pes cavovarus with a fixed plantar flexed first ray and a passively correctable tarsus due to Charcot-Marie-Tooth disease. PATIENTS AND METHODS: Between January 1995 and July 2005, thirty-three patients with pes cavovarus deformity due to Charcot-Marie-Tooth disease were included. All patients had in common that prior to surgery the hindfoot was passively still adequate correctable at the talonavicular joint. The Coleman block test was performed to establish with certainty that hindfoot varus was a secondary deformity. Fourteen patients were male (21 feet) and nineteen were female (31 feet). Mean age at surgery was 28.1 years (range 13-59 years). Mean follow-up time was 56.9 months (range 13-153 months). Evaluation consisted of physical examination of all patients with assessment of early and late complications. The validated Foot Function Index (FFI) was used to measure pain and impairment. Patients' satisfaction was assessed by a Quality of Care Through the Patients' Eyes (QUOTE) questionnaire. INTERVENTION: Surgical correction of cavovarus foot deformity consisted of dorsiflexion osteotomy at the base of the first metatarsal combined with tendon transfers. Secondary calcaneal osteotomy was performed in case of persistent varus of the calcaneus. RESULTS: No major complications were seen. Recurrence of cavovarus deformity in two feet resulted in triple arthrodesis 37 and 64 months postoperatively. The FFI 5-point score for pain improved from a mean 29.3% to a mean 14.8% (p=0.005). The score for disability improved from a mean 37.8% to a mean 23.5% (p<0.001). Patients' satisfaction was assessed by the QUOTE questionnaire. Seventy percent of the patients could walk barefoot after the operation and 77% of the patients had less pain after surgery. Pressure callosities diminished in 81%. Foot function was considered better after surgery by 84%. Ninety percent was satisfied with the correction of the deformity. CONCLUSIONS: First ray dorsiflexion osteotomy combined with tendon transfers is a good and consistent solution to realign the foot and provides short-term to mid-term satisfactory results in 90% of patients with a rigid forefoot cavus deformity due to plantar flexion of the first ray and with a still passively reducible tarsus.

Foot Build Registration System (FBRS) to evaluate foot posture: a reliability study with healthy subjects and patients with Charcot-Marie-Tooth disease.

BACKGROUND: To follow the weight bearing foot posture in subjects, a measurement tool using digital photography was developed, Foot Build Registration System (FBRS) (Fig. 1) [M. Van der Cruijsen, Voetvorm registratie systeem, Boxmeer (1999).]. This study's objective was to investigate the reproducibility of FBRS measurements in healthy feet and feet of patients with Charcot-Marie-Tooth disease (CMT). METHODS: Reproducibility and reliability studies were performed in several foot views in healthy and CMT patients. RESULTS: These studies showed that the variability of the 95% prediction limit depended upon the foot view being studied and whether markers had been drawn. Some individuals had a higher intra-individual variability than others. Limiting data collection to those individuals with a SD<3.5 degrees for a series of five or more photographs per view improved the 95% prediction limits. These varied between 2.8 degrees and 7.7 degrees. CONCLUSIONS: If the differences found between registration are greater than the abovementioned, values can be attributed to time or operative management for healthy and CMT patients and not to measurement error.

Short-term results of our first 49 Scandanavian total ankle replacements (STAR).

BACKGROUND: Forty-seven consecutive patients treated for ankle arthritis with a Scandinavian total ankle replacement (STAR) by one surgeon were investigated retrospectively. MATERIALS AND METHODS: A modification of the Foot Function Index (FFI), which scores pain and task difficulties, was followed prospectively. Patients were assessed clinically and radiologically. Failure was defined as revision of the prosthesis or arthrodesis for any reason. RESULTS: In 47 patients (16 male, 31 female) 49 total ankle replacements were carried out between May 1999 and June 2004. Indication for surgery was end stage arthritis for rheumatoid arthritis in 29 cases, post-traumatic arthritis in 12, osteoarthritis in five and arthritis secondary to degenerative flatfoot in three. Mean followup time was 28 (12 to 67) months. The modified FFI (range, 0 to 100, a high score meaning more pain and disability) improved significantly from 59 before to 35 after surgery. The mean postoperative Kofoed ankle score was 68. Sixteen procedures were complicated by fractures or temporary neurological damage. At the time of followup, 45 prostheses survived, while four replacements had failed. Radiological examination at followup showed radiolucent lines, osteolysis, and malposition of the components in 31 cases. CONCLUSION: Our results are comparable with those reported in the literature. The clinical outcome improved significantly. Due to aseptic and septic loosening, 8.2% of the prosthesis failed.

Assessing the subtalar joint: the Brodén view revisited.

We prospectively evaluated subtalar inversion stress views (Brodén view) with inversion stress views on helical CT in a group of 10 patients with unilateral instability. The contralateral, asymptomatic ankle was used as control. All patients were examined with inversion stress views on plain stress radiography and helical CT. Subtalar tilt was demonstrated in all cases on conventional stress radiography. Helical CT didn't show tilting in any of the patients except in the subluxated posteromedial part of the subtalar joint. Our data do not support prior reports that the Brodén view is useful for screening patients with subtalar instability.

Posttraumatic subchondral bone contusions and fractures of the talotibial joint: occurrence of "kissing" lesions.

OBJECTIVE: The objective of this study was to determine the presence and location of subchondral bone contusions, fractures, and "kissing" lesions of the talotibial joint after a sprain of the ankle shown on MR imaging. MATERIALS AND METHODS: We retrospectively reviewed the images of all consecutive patients who underwent MR imaging of the ankle after acute or recurrent sprain occurring between January and December 1997. The number and location of subchondral contusions or fractures revealed on MR imaging were recorded, and a comparison was made with the radiographs obtained for each patient. RESULTS: Of the 146 ankles, 42 osteochondral lesions were revealed on MR imaging in 26 ankles (18%) involving 23 patients. Twenty-three lesions were localized in the dome of the talus and 19, in the tibiofibular plafond. In 16 (11%) of the 146 ankles, the lesions were present in the opposing bones of the joint ("kissing" lesions). Only six of the 12 talar fractures and none of the tibial fractures involving the 26 ankles were seen on conventional radiography. CONCLUSION: Subchondral lesions in the talus and tibia are relatively common after ankle trauma, occurring in 18% of patients in our series. Kissing lesions were present in more than half of the lesions in these patients.

Psychomotor, Cognitive, extrapyramidal, and affective functions of healthy volunteers during treatment with an atypical (amisulpride) and a classic (haloperidol) antipsychotic.

The primary objective of this study was to compare the objective and subjective effects of amisulpride with those of a classic antipsychotic, haloperidol, when both were given to healthy volunteers in representative therapeutic doses over 5 days. The secondary objective was to compare the effects of relatively low and high doses of amisulpride to confirm the suspected duality of its pharmacologic activity. Twenty-one subjects participated in the four-way, randomized, double-blind, crossover study with repeated daily doses of amisulpride 50 mg, amisulpride 400 mg, haloperidol 4 mg, and placebo. Subjects were institutionalized during treatment periods and were under 24-hour medical supervision. They underwent a series of psychomotor and cognitive tests 1 hour before and 3 and 6 hours after dosing on days 1 and 5. Their extrapyramidal disturbances and drug-related feelings were assessed at the end of each replication. Psychiatric interviews and ratings of depression, subjective well-being, and negative symptoms occurred on day 4. Amisulpride 50 mg had no significant effect on any parameter. Amisulpride 400 mg had several adverse effects on psychomotor and, although less severe, on cognitive performance on the fifth day only. Amisulpride 400 mg produced no significant extrapyramidal disturbances in the group as a whole, although it may have in some individual subjects. Also, it produced no signs of mental disturbances on clinical rating scales or during a structured psychiatric interview. Haloperidol ubiquitously impaired psychomotor and cognitive performance in a similar fashion after the first and the final doses. It produced extrapyramidal disturbances in nearly every subject, the most common being akathisia and the most severe, in the case of one individual, being acute dystonia. Unlike amisulpride, haloperidol produced a number of mental disturbances, the most noteworthy being negative symptoms. Amisulpride seems to be a well-tolerated drug. Its side effects should be much less troublesome to patients using the drug on a long-term basis than those of classic antipsychotics, like haloperidol.

Stress radiography and stress examination of the talocrural and subtalar joint on helical computed tomography.

The main objective of this study was to compare subtalar inversion stress views using the Brodén view with inversion stress views on helical computed tomography (CT). One of the drawbacks of routine radiography is the imaging of three-dimensional structures in a two-dimensional plane. We investigated whether the use of helical CT would lead to a more objective and clearer measurable method to determine the amount of tilt in the subtalar joint. A group of 15 patients with unilateral chronic instability complaints and clinically suspected subtalar instability was examined. The contralateral asymptomatic foot was used as control. A variable amount of subtalar tilt (range, 4 degrees to 18 degrees) was demonstrated in all cases on stress radiographs, without finding significant difference between the symptomatic and asymptomatic feet. However, contrary to the findings at the talocrural level, subtalar tilt was found in none of the patients using helical CT. Thus, we now doubt that the tilt seen during stress examination using the Brodén view is the true amount of tilt. It may be that the lateral opening, seen on these radiographs, largely results from imaging two planes that have made a translatory and rotary movement relative to each other in an oblique direction. It is concluded that the Brodén stress examination might not be useful for screening patients with subtalar instability. Associated anomalies not visible on the radiographs were detected by helical CT. In four cases, narrowing of the articular cartilage and irregular and hypertrophic bone formation at the middle facet joint of the subtalar joints were found. It is likely that these changes cause disturbance of function of this joint and it is suggested that the subjective complaint of instability with "giving way" is not only caused by hypermobility, but can be caused by other disturbance of normal motion.

Expressed emotion on long-stay wards.

We examined the influence of an educational programme on nurses' level of expressed emotion (EE), on ward climate and on social functioning and psychopathology of hospitalized schizophrenic patients. Nurses and patients were from long-stay wards of six Dutch psychiatric hospitals. Despite an increase of nurses' knowledge about schizophrenia we did not find measurable effects on nurses' levels of EE. According to the five minute speech sample method, a third of the nurses participating in this study had a high level of expressed emotion, mainly consisting of criticism. This was a rather stable pattern. Patients, however, were reluctant to give their nurses high EE ratings on the level of expressed emotion scale. Psychopathology was not influenced by the educational programme, but social functioning of patients was related to EE in nurses. Moreover, we found a significant decline in the number of restrictive ward rules at follow-up. We conclude that, while it may be difficult to detect changes in EE level after an educational programme for nurses, there nevertheless appear to be measurable benefits for patients.

Peroneus longus and tibialis anterior muscle activity in the stance phase. A quantified electromyographic study of 10 controls and 25 patients with chronic ankle instability.

The electromyographic activity of the peroneus longus and anterior tibial muscles of 25 patients with chronic ankle instability (18 patients with bilateral symptoms and 7 patients with unilateral complaints) and 10 controls was registered during the stance phase under different walking conditions. With balance secured by external support, there was a variable amount of peroneal activity, most of which was found in the third quarter of stance. A high increase in peroneus longus activity starting after foot-flat was found when subjects had to maintain balance in a natural way. No difference in peroneal activity was found in relation to instability complaints. It is thought that the peroneus longus serves to maintain balance, that this function decreases with increase of speed and that one cannot rely on this muscle to prevent an inversion injury during normal walking. The anterior tibial muscle was predominantly active in the first quarter after heel contact. An increase in activity in the second quarter as an effect of loss of secured balance suggests that this muscle plays some part in balance control, but this is not its main function. A significant increase in tibialis anterior activity was found in patients with bilateral instability. No significant difference was found between the symptomatic and asymptomatic leg of patients with unilateral instability under the same walking conditions. These findings suggest changes in central control.

Differential effects of the D1-DA receptor antagonist SCH39166 on positive and negative symptoms of schizophrenia.

In the present open study the effects of the D1-dopamine antagonist SCH 39166 on positive and negative symptoms of schizophrenia (DSM-IIIR) were investigated. SCH 39166 was given orally according to a fixed dosage schedule (day 1: 25 mg b.i.d; day 4: 50 mg b.i.d.; day 7: 100 mg b.i.d.; day 18: 200 mg b.i.d.; day 21: 225 mg b.i.d.). Seven patients completed 2 weeks, and five patients completed the study. The reason for premature withdrawal was lack of efficacy or refusal to take SCH 39166. In none of the patients a reduction of the BPRS or CGI score was found. As measured with the PANSS, a significant reduction was observed in the score of the negative subscale, whereas the positive symptoms scale and general psychopathology score remained unaffected. Akathisia, rigidity and hypokinesia were reported occasionally, although only mild in severity. The results of the present study do not support the hypothesis that D1-dopamine antagonists are clinically effective antipsychotics in schizophrenia, considering the fact that SCH 39166 had no effect on positive symptoms. The present study provides circumstantial evidence for an effect of SCH 39166 on negative symptoms.

Stress radiography of the talocrural and subtalar joints.

The object of this investigation was to determine a possible subtalar component in a group of 33 patients with chronic ankle instability. A group of 10 subjects without ankle/foot symptoms acted as controls. A standardized radiographic assessment of talar and simultaneous subtalar tilt was made. A hinge device to stress the joints and a specific subtalar stress view (Brodén view) were used under fluoroscopic control. Radiographs were made with the feet: (1) in neutral position, (2) after inversion with moderate force until the point of fair restraint (step 1), and (3) after inverting with more force as far as the conditions would allow (step 2). An increase of talar tilt between step 1 and step 2 was only found in feet that were symptomatic. This suggests that this increase is only possible when lateral ligaments are damaged. Further research is necessary to determine whether this finding can serve as a parameter to discriminate between physiological and abnormal talar tilt. A wide range of subtalar motion was found in both symptomatic and asymptomatic feet. With the present method, practically all subtalar joints showed some loss of congruity and medial shift of the calcaneus in relation to the talus. This could not be correlated with ankle instability at the talocrural joint. The consequence of the use of different subtalar stress methods has so far received little attention and is discussed.

Testing the effects of hypnotics on memory via the telephone: fact or fiction?

The two benzodiazapines used in this experiment, namely midazolam and flunitrazepam, have both been shown to have effects on memory processing in laboratory studies. In spite of the potential hazards involved in real life testing, it should be possible to replicate such findings in everyday environments and it is argued that a successful replication would be a very meaningful extension to the existing laboratory data. The present study was successful in producing significant "hangover" effects in healthy volunteers using a novel "user-friendly" telephone testing technique. Compared to placebo, the two hypnotics reduced speed of processing in tasks which required retrieval from long-term semantic memory (semantic verification) and the manipulation of material in working memory (syntactic reasoning). We suggest that this new method offers the potential for carrying out large-scale psychopharmacological studies with real patients and achieves a meaningful step forward in the search for ecological validity.

Specific skills and social competence in schizophrenia.

Generalization of skills is a major problem in social skills training for schizophrenic patients. Assessment of skills is mostly not based on objective indices of specific skill deficits. The results of this study show that global competence of schizophrenics can be differentiated from specific competence. Global competence was found to be related to symptoms, whereas specific competence was not. No support was found for the assumption that social dysfunctions are caused by negative symptoms. Social perception and positive symptoms did explain a substantial part of the variance of global competence. It is therefore concluded that neither global incompetence nor negative symptoms should be used as an indication for social skills training.