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M Haerle

Publications and source records attributed to M Haerle.

13 recordsLinked to original sources
PubMed2006

[Memantine and Complex Regional Pain Syndrome (CRPS): effects of treatment and cortical reorganisation].

BACKGROUND: In recent studies a central nervous system involvement in the pathogenesis of Complex Regional Pain Syndrome (CRPS) was suggested, stimulating the introduction of central acting drugs. Animal studies have demonstrated an increased expression of the N-methyl-D-aspartate (NMDA) receptors in experimental neuropathic pain. PURPOSE: The aim of this study was to investigate the relationship between NMDA receptor blockers and CRPS. METHOD: Three patients suffering from CRPS of one upper extremity where treated with oral NMDA antagonist Memantine for eight weeks. Patients expressed their pain levels with a visual analog scale ranging from zero to ten at rest and after fist clenching. Furthermore, the range of movement of the fingers and the wrist were documented. To assess force, a pinchmeter and a dynamometer were used. Cortical reorganisation was studied with functional Magnetic Resonance Imaging (fMRI) and Magnetoencephalography (MEG). RESULTS: Six months after treatment with Memantine no rest pain was present in any of the patients. Furthermore, an increase in finger movement was observed after six-month follow-up with no deficits and free movement ranges. Additionally, wrist movement was improved and an increase of force was measured after six months with the dynamometer and the pinchmeter. Moreover the functional impairment, cortical reorganisation was observed in all patients before treatment. These changes returned to a normal pattern after eight weeks of treatment with Memantine. CONCLUSION: These first results demonstrate central nervous system involvement in the development and maintenance of CRPS. The results (functional, pain, fMRI, MEG) after treatment with Memantine indicate the importance of the NMDA receptor system in neuropathic pain syndromes and provide a promising approach for the treatment of CRPS.

Administration, Oral↗
PubMed2006

[Tissue engineering of peripheral nerves].

BACKGROUND: In spite of considerable progress in microsurgical techniques, the treatment of long distance defects in peripheral nerves remains challenging for the surgeon. Autologous nerve grafting has been the only applicable procedure to overcome such defects in the past. Due to the known disadvantages of this procedure (neuroma formation and sensory deficits at the donor-site, limited availability of donor-material, etc.) and impaired regenerative results, different tubulisation techniques are discussed more frequently as alternatives to the autologous nerve grafts. AIM OF THE STUDY: In this work, the authors summarise their experiences and results with different synthetically developed materials, cellular and acellular tubes and venous conduits for the reconstruction of peripheral nerve defects. MATERIAL AND METHODS: To analyse peripheral nerve regeneration, we utilised a median nerve model in rats. In these studies nerve gaps up to 40 mm were induced. Guiding tubes of various materials (trimethylene carbonate-epsilon-caprolactone, polyethylene, veins, and collagen) were employed. Furthermore, we introduced Schwann cells as cellular elements into some of the trimethylene carbonate-epsilon-caprolactone tubes. The longest postoperative observation period was nine months. RESULTS: The results demonstrated that only in the case of cellular filled tubes (syngenic Schwann cells) did regeneration occur across the 20 mm gap. This regeneration was comparable to that induced after autologous grafting. Across a 40 mm gap the autologous graft demonstrated the best results.

Animals↗
PubMed2005

[Vascularized bone graft in carpal bone reconstruction].

We report our experience of vascularized bone graft harvested from the volar aspect of the distal radius for carpal bone reconstruction. Thirty cadaveric dissections showed in all cases the volar carpal artery which born from the radial artery. Between 1994 to 2001, we treated 87 scaphoid non-unions with an average follow-up of 41 months (range 6 to 65 months). Union was obtained in 80 patients (92%) with an average delay of 8.6 weeks (range 6 to 24). Between 1994 to 2000 we treated 22 patients with a Kienbock's disease. A radius shortening was always added to the revascularization of lunate by this vascularized bone graft. Preoperative and postoperative MRI was systematically done. The average follow-up was 55 months (range 24 to 92 months). MRI showed healing with good revascularization in 16 cases (74%). Lesions of lunate were stabilized in five cases and we had one failure with secondary palliative procedure. This simple but meticulous technique needs only one approach and allows a sufficient revascularisation.

Adolescent↗
PubMed2004

Long-term results on abduction and external rotation of the shoulder after latissimus dorsi transfer for sequelae of obstetric palsy.

Transfer of the latissimus dorsi to the rotator cuff is widely used for restoring shoulder abduction and external rotation in sequelae of brachial plexus palsy; however, its long-term results are not well known. Because persistence of clinical benefits is crucial for children with brachial plexus palsy, the aim of our study was to evaluate retrospectively the long-term results of this transfer in 203 children. Patients were classified according to type of paralysis (C5-C6, C5-C6-C7, and complete), degree of preoperative shoulder function according to Gilbert, and age at surgery. Active abduction and external rotation were measured at 1, 3, 6, 10, and 15 years and the results were analyzed statistically. Children with sequelae of C5-C6 palsy gained in abduction and external rotation more than children with C5-C6-C7 or complete palsy. Patients with mild preoperative shoulder dysfunction achieved the best results. The data showed the clinical results were related to the type of paralysis and to preoperative shoulder function, but not to age at surgery. They also showed progressive deterioration of abduction began at 6 years despite preserved active external rotation.

Adolescent↗
PubMed2003

Collateral arterial pathways in the forearm.

We studied the forearm vessels and the palmar carpal arch in 41 fresh cadaver upper limbs injected with colored latex solutions. In one case, we found a complete occlusion of the radial artery. Collateralization was evident through the anterior interosseous artery, its palmar branch and the radial part of the palmar carpal arch. The diameters of these vessels were significantly enlarged. The dissections of the remaining 40 arms demonstrated that these vessels offer a possible collateralization pathway via the anterior interosseous artery. One hypothesis for the formation of such collateralization might be a dominant blood flow of the radial artery to the hand. Therefore, it seems sensible to preserve the communication between the anterior interosseous and the radial arteries through the palmar carpal arch, raising the radial artery for surgery.

Arteries↗
PubMed2003

Vascular anatomy of the palmar surfaces of the distal radius and ulna: its relevance to pedicled bone grafts at the distal palmar forearm.

The potential for harvesting vascularized bone grafts from the palmar surface of the distal radius has been studied in 40 arms of fresh cadavers which had previously been injected with coloured latex solution. It was found that vascularized grafts can be pedicled on the radial part of the palmar carpal arterial arch. If a longer pedicle is required, the bone graft can be pedicled on the anterior branch of the anterior interosseous artery with retrograde flow occurring from the palmar carpal arch.

Bone Transplantation↗
PubMed2002

Dominances in finger arteries.

We studied the patterns of dominance in the palmar digital arteries of the fingers in 39 fresh cadaver arms which had been injected with coloured latex solution. We also performed photoplethysmographic studies in 20 hands. The ulnar digital artery in the index finger and the radial digital artery of the little finger were usually dominant, and their counterparts were slim and often hypoplastic. The findings are relevant to digit revascularization and might influence the planning of digital island-flaps or toe transfers.

Fingers↗
PubMed2001

Multiple frequency steady-state evoked magnetic field mapping of digit representation in primary somatosensory cortex.

Magnetic source imaging of multiple frequency steady-state somatosensory evoked responses was examined using a 151-channel magnetoencephalography (MEG) system and a dual-channel electrical stimulator. Somatotopy of digit representation was studied in healthy subjects and effects of injury-related cortical plasticity in patients with unilateral transections of the median or the ulnar nerve. Dipole source locations exhibited somatotopic order with overlap between neighboring digits. In two of three nerve injury patients evidence for cortical reorganization was found. The location of sources related to digits neighboring deafferented digits was changed and their dipole moments were enlarged by comparsion with the sources related to contralateral homologue control digits. As a basis for magnetic source imaging, the recording of multiple frequency somatosensory steady-state evoked responses may be a viable and time saving alternative to the recording of transient evoked responses.

Adult↗
PubMed2000

Cortical reorganization after digit-to-hand replantation.

Functional recovery after digit-to-hand replantation depends on the interaction of various factors. In addition to peripheral mechanisms, cortical and subcortical reorganization of digit representation may play a substantial role in the recovery process. However, cortical processes during the first months after replantation are not well understood. In this 25-year-old man who had traumatically lost digits II to V (DII-V) on his right hand, the authors used magnetoencephalographic source imaging to document the recovery of somatosensory cortical responses after tactile stimulation at four sites on the replanted digits. Successful replantation of DIV and DV was accomplished at the original position of DIII and DIV with mixed innervation. Cortical evoked fields could be recorded starting from the 10th week after digit-to-hand replantation. Initially, signals from all sites showed decreased amplitudes and prolonged latencies. In the subsequent six recordings obtained between the 12th and 55th week postreplantation, a continuous increase in amplitude but only a slight recovery of latencies were observed. Components of the recorded somatosensory evoked fields were localized in the primary somatosensory cortex (SI). The localizations of the replanted DIV showed a gradual lateral-inferior shift in the somatosensory cortex over time, indicating cortical reorganization caused by altered peripheral input. The authors infer from this shift that the original cortical area of the missing finger (DII) was taken over by the replanted finger. From these data the authors conclude that magnetic source imaging might be a reliable noninvasive method to evaluate surgical nerve repair and that cortical reorganization of SI is involved in the regeneration process following peripheral nerve injury.

Adult↗
PubMed1998

Vascularized bone graft from the palmar carpal artery for treatment of scaphoid nonunion.

We report the use of a bone graft harvested from the palmar and ulnar aspect of the distal radius and vascularized by the palmar carpal artery for the treatment of scaphoid nonunion in 17 patients, ten of whom had already had unsuccessful surgery. Union was obtained in all cases at an average of 60 days (range, 45-90 days). The average follow-up was 16 months (range, 12-36 months). There were no failures.

Adolescent↗
PubMed1997

[Standardization of evaluation and classification of disability manifestations in traumatic brachial plexus birth injury-induced paralysis].

The classification of miscellaneous clinical features in obstetric palsies is difficult due to variations during growth, regeneration, plexus repair and secondary surgery. Any useful comparison of different forms of therapy requires universally recognised norms of evaluation. Several proposals have already found clinical application. Their employment will help to unify the results of our evaluation.

Arm↗