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Yu-Dong Gu

Publications and source records attributed to Yu-Dong Gu.

18 recordsLinked to original sources
PubMed2007

Contralateral C7 transfer for the treatment of brachial plexus root avulsions in children - a report of 12 cases.

PURPOSE: To retrospectively determine the risks and benefits of contralateral C7 nerve root transfer in infants and children. METHODS: In 12 infants and children with brachial plexus root avulsions from birth injury or other trauma, the common trunk of the contralateral C7 root was transferred to the trunk, division, cord, or nerve branch(es) on the affected side with 2 different types of interposition grafts. The surgery was performed in 1 stage for 5 patients and in 2 stages for 7 patients. RESULTS: Patients were followed up for a mean of 42 months, with a minimum of 21 months. Noteworthy function (> or = M2+, modified British Medical Research Council grading system) was gained in 10 of 12 patients and sensory function (> or = S3, British Medical Research Council grading system) was gained in all patients. Improvements in strength and sensation were accompanied by little synchronous motion and sensibility changes in the donor limb in 7 children, to whom the repaired nerves were those innervating the shoulder and/or elbow or both the musculocutaneous and median nerves. In addition to slight damage to the sensory function of the median nerve, 2 infants also had temporarily reduced shoulder abduction on the healthy side. CONCLUSIONS: For contralateral C7 transfer in infants and children with brachial plexus root avulsions, the deficit created by the procedure is minimal and motor and sensory function is gained. Transfer of the contralateral C7 root to different nerves for a child may improve the quality of functional recovery. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic, Level IV.

Brachial Plexus Neuropathies↗
PubMed2006

[Long-term impact of transfer of phrenic nerve on respiratory system of children: a clinical study of 34 cases].

OBJECTIVE: To study the long-term impact of transfer of phrenic nerve on respiratory system of children. METHODS: Thirty-four children with brachial plexus injury, 25 boys and 9 girls, underwent transfer of phrenic nerve and were divided into 3 groups according to the age when they underwent operation: group of the age of 0 - 12 months (n = 17), group of 13 - 36 months (n = 11), and group of 37 - 60 months (n = 6). Thirty-four sex, height, and body weight-matched healthy children were used as controls. Follow-up, including physical examination, pulmonary function examination (tidal volume, ventilation, etc), blood gas analysis, and chest radiography, was conducted for 4.03 years (3 - 7 years). RESULTS: The values of maximum vital capacity of the group of 0 - 12 months and group of 13 - 36 months were 1.0 L +/- 0.2 L and 1.2 L +/- 0.4 L, both significantly lower than those of the corresponding control groups (1.3 L +/- 0.3 L and 1.4 L +/- 0.5 L, both P < 0.05). The values of one-second vital capacity of the group of 0 - 12 months and group of 13 - 36 months were 0.8 L +/- 0.1 L and 0.9 L +/- 0.1 L, both significantly lower than those of the corresponding control groups (1.0 L +/- 0.1 L and 1.0 L +/- 0.1 L, both P < 0.05). However, the values of the maximum vital capacity and one-second vital capacity of the group of 37 - 60 months were 1.6 L +/- 0.3 L and 1.8 L +/- 0.5 L respectively, both not significantly different from those of the controls (both P > 0.05). The results of blood gas analysis of the 3 operation groups were not significantly different from those of the corresponding controls. Chest radiograph showed that the diaphragm top was raised by 1.93 intercostal spaces (0.5 - 3.5 intercostal spaces) in comparison with the contralateral sides with significant differences between the group of 0 - 12 months and the group of 13 - 36 months and between the group of 0 - 12 months and the group of 37 - 60 months (both P < 0.05). The recurrent respiratory infection rate and of the groups of 0 - 12 months and 13 - 36 months were 47.1% and 27.3% respectively, both significantly higher than that of the group of 37 - 60 months (0%). The thorax deformity rate of the groups of 0 - 12 months and 13 - 36 months were 41.2% and 9.1% respectively, both significantly higher than that of the group of 37 - 60 months (0%). Three of the children in the group of 0 - 12 months (17.6%) had digestive system symptoms. CONCLUSION: Transfer of phrenic nerve operated on children younger than 3 years may cause abnormalities of respiratory system, thorax, and digestive system. The younger the patients the more severe the consequences of the operation. The children older than 3 years tolerate the operation better.

Age Factors↗
PubMed2005

Comparative clinic study on vascularized and nonvascularized full-length phrenic nerve transfer.

In order to understand whether the vascularizing procedure has any clinical value in nerve transfer and grafting, we compared nonvascularized and vascularized full-length phrenic never transfers in patients with a brachial plexus injury. Full-length phrenic nerve transfer to the musculocutaneous nerve had been conducted by the technique of video-assisted thoracic surgery in 15 patients. Three kinds of procedures were carried out. The first involved retaining the initial point of the phrenic nerve and dissecting the full-length distal nerve. The second involved keeping the cervical segment and isolating the thoracic segment of the phrenic nerve. The last involved vascularized phrenic nerve transfer. All these phrenic nerves were sutured to musculocutaneous nerves. After 28-35 months, the results of electrophysiology and function of the biceps brachii muscle were compared. All three procedures had no significant differences and led to the same functional recovery of the biceps brachii muscle after at least 28 months of follow-up. In conclusion, the vascularizing procedure had little clinical value, not only in full-length phrenic nerve transfer, but also in nerve grafting irrespective of the length of the gap, when the recipient bed had normal vascularity.

Adult↗
PubMed2005

Selective neurotization of the median nerve in the arm to treat brachial plexus palsy. Surgical technique.

BACKGROUND: The current method for treatment of median nerve palsy after a brachial plexus injury is unpredictable. On the basis of an anatomic study of the median nerve in the arm, we present a new method of selective neurotization of the median nerve. METHODS: Internal topographic features of the fascicular groups of the median nerve were observed in seventeen cadavera. On the basis of the anatomical results, selective neurotization of the posterior fascicular group of the median nerve in the arm was performed in one patient with a complete brachial plexus palsy. RESULTS: In the distal half of the arm, the branches of the median nerve consistently collect into three fascicular groups, which are located at the anterior, middle, and posterior parts of the median nerve trunk. The anterior fascicular group is composed of the branches to the pronator teres and the flexor carpi radialis, the posterior fascicular group is composed mainly of the anterior interosseous nerve and the branches to the palmaris longus, and the middle fascicular group is made up mostly of the branches to the hand and the flexor digitorum superficialis. A transfer of the full length of the phrenic nerve was used to selectively reinnervate the posterior fascicular group of the median nerve in a patient with a complete brachial plexus palsy. The muscles supplied by the posterior fascicular group regained Grade-4 power, according to the system of the Medical Research Council, sixteen months after surgery. CONCLUSIONS: The typical arrangement of the fascicular groups of the median nerve in the arm favors the technique of selective neurotization, which has been used effectively in one patient to date.

Brachial Plexus Neuropathies↗
PubMed2005

Pulmonary function after complete unilateral phrenic nerve transection.

OBJECT: The status of pulmonary function following phrenic nerve transfer surgery is still largely unknown because of the high degree of variability in the accessory phrenic nerve that may be involved. In the present study, pulmonary functions were assessed in patients before and after full-length phrenic nerve transfer surgery, in whom the phrenic nerve was severed at a location just before its entry into the diaphragm. METHODS: Fifteen patients (average age 27.4 years) with complete brachial plexus palsy underwent full-length phrenic nerve transfer. The phrenic nerve was harvested from the thoracic cavity by means of video-assisted thoracic surgery and then transferred to the musculocutaneous nerve. Postoperative pulmonary functions were retrospectively analyzed. Patients underwent follow-up evaluation for 42 to 48 months; four patients were eventually lost to follow up. Although no patient experienced pulmonary problems following the surgery, all sustained varying degrees of diaphragmatic paralysis and elevation (for 1-1.5 intercostal spaces) on the surgically treated side as seen on chest x-ray films. Pulmonary functional parameters, including vital capacity, vital capacity in percentage of predicted values, residual volume, total lung capacity, forced vital capacity, and forced expiratory volume in 1 second, recovered to preoperative levels by 1 year postsurgery. In contrast, the postoperative maximal inspiratory pressure value was significantly decreased compared with the predicted values (average decrease approximately 20%) in all of the patients, even at 4 years after the surgery. CONCLUSIONS: In young patients with healthy lung function, unilateral phrenic nerve transection surgery can cause unilateral diaphragmatic paralysis and reduce the inspiration muscle force; however, most pulmonary function parameters gradually recover to preoperative levels within 1 year.

Adolescent↗
PubMed2005

The role of the large superficial vein in survival of proximally based versus distally based sural veno-neuro-fasciocutaneous flaps in a rabbit model.

A sural veno-neuro-fasciocutaneous flap in the New Zealand White rabbit was developed, and the role of the large subcutaneous lesser saphenous vein was investigated in proximally based versus distally based flaps. Retrograde dye injection showed that the lesser saphenous vein in rabbits has many valves with strong resistance against reflux. Twenty rabbits were randomly allocated into four groups of 10 flaps each. Group I consisted of proximally based flaps with the lesser saphenous vein intact (outflow) in the veno-neuro-adipofascial pedicle. Group II also consisted of proximally based flaps but the lesser saphenous vein was ligated at 1 cm proximal to the pedicle. Group III consisted of distally based flaps with the lesser saphenous vein intact (inflow) in the veno-neuro-adipofascial pedicle. Group IV also consisted of distally based flaps, but the lesser saphenous vein was ligated at 1 cm distal to the pedicle. The results showed that the mean flap survival area in group I (88.8 percent) was statistically higher than that in group II (62.6 percent, p < 0.001), and was higher in group IV (55.5 percent) than in group III (22.7 percent, p < 0.01). However, group II and group IV had no significant difference (p > 0.05). This experiment demonstrated that flap viability is determined by its intrinsic vascularization, both arterial and venous. The large superficial subcutaneous vein has a positive role (venous outflow) in proximally based flaps but a negative role (venous inflow) in distally based flaps. If the effect of the large subcutaneous vein is excluded, distally based flaps are not inherently inferior to proximally based flaps.

Animals↗
PubMed2004

[Study of expression of slit2 mRNA in rats of different age after sciatic nerve injury].

OBJECTIVE: To determine the age-related expression features of slit2 mRNA at various intervals at the proximal and distal parts of sciatic nerve during re-innervation after severance injury, and to investigate the molecular biological reason why co-contraction occurs more commonly in the young rats than in the adults after peripheral nerve injury. METHODS: The right sciatic nerve was transected sharply at the midthigh in the young and adult rats, 28 in each group. The proximal and distal stumps were inserted into a medical silicone tube with a gap of 3 mm. Before the injury, and 1, 3 and 7 days (6 rats at each interval) after sciatic nerve severance injury, both stumps of the sciatic nerve were harvested. Reverse transcription polymerase chain reaction (RT-PCR) was use to examine the expression of slit2 mRNA in the young and adult group rats. In situ hybridization was done to detect the cell location of slit2 mRNA expression in young and adult rats, 4 rats in each group, 2 rats used before the injury and 2 rats used on the postoperative third day. RESULTS: RT-PCR results suggested that slit2 mRNA at both stumps was significantly lower in the young group of rats than in the adult except that at the proximal part on the postoperative 7th day. There was statistically significant difference (P < 0.01). In situ hybridization studies indicated that the slit2 mRNA was specifically expressed in the cytoplasm of Schwann cells both in the young and adult rats before injury and 3 days after injury. CONCLUSION: The expression of slit2 mRNA by Schwann cells in the young rats is lower than that in the adult rats after peripheral nerve injury. These findings suggests the lower expression of chemotactic factor (slit2) by Schwann cells in the young group is likely to be the molecular biological reason for the higher incidence of co-contraction between agonists and antagonists in the younger rats.

Age Factors↗
PubMed2004

Comparative experimental study on treatment outcome of nerve transfer, using selective C7 nerve root vs. phrenic nerve.

The treatment outcome of nerve transfer using the C7 nerve root or phrenic nerve was compared in a rat experiment. One hundred and twenty SD rats were divided into two groups, one undergoing phrenic nerve transfer to the musculocutaneous nerve, and the other partial ipsilateral C7 (anteriolateral fascicles of the anterior division) to the musculocutaneous nerve. Neurotization outcomes of the two groups were evaluated by comparing the electrophysiologic, histologic, and myophysiologic changes of the biceps muscle. No significant differences were found between parameters from the phrenic nerve transfer group and those from the ipsilateral C7 nerve transfer group. This indicates that the treatment outcome of selective ipsilateral C7 transfer is comparable to that of phrenic nerve transfer. It is the surgery of choice in treating brachial plexus upper-trunk avulsion accompanied by phrenic nerve injury.

Animals↗
PubMed2004

Electrophysiologic study of influence on C7 innervated muscles after transection of different C7 fascicles.

An experimental study was conducted to observe the electrophysiologic changes in C7 innervated muscles following transection of different fascicles of C7 nerve root in the brachial plexus with already transected C5 and C6. Twenty-four Sprague-Dawley rats were randomized into groups A, B, and C. C5 and C6 transection, C5, C6, and partial C7 (anteriolateral fascicles of the anterior division) transection, and C5, C6, and C7 transection were done in group A, B, and C, respectively. One month postoperatively, compound muscle action potentials of the latissimus dorsi, triceps, and extensor digitorum communis were recorded. Decreased amplitude and a prolonged latent period were seen in all three muscles of group C. No obvious changes, however, were found in groups A and B. This suggests that when the upper trunk of the brachial plexus is injured, partial transection of C7 does not obviously impair C7 innervated muscle function. Selective ipsilateral C7 transfer is safe for the treatment of upper-trunk avulsion.

Action Potentials↗
PubMed2004

Modified distally based peroneal artery perforator flap for reconstruction of foot and ankle.

The distally based sural fasciocutaneous flap has been used widely for reconstruction of foot and ankle soft-tissue defects. Here we report on a series of cases of foot and ankle reconstruction with a modified distally based sural flap. The vascular pedicle of the flap includes an axial perforator branch of the peroneal artery and two concomitant veins. This modified distally based perforator flap, measuring around 17 x 6 cm to 30 x 10 cm in size, was transferred for coverage of foot and ankle soft-tissue defects in 7 cases. All flaps survived completely. Neither arterial ischemia nor venous congestion was noted. As compared to other distally based sural flaps with neuro-veno-adipo-fascial pedicles, this modified sural flap with a thin perforator pedicle is easily rotated. The flap can obtain abundant blood supply through both axial perforator and longitudinal chain-linked vascular plexuses, and does not have the venous reflow problem. In conclusion, the invention of this perforator fasciocutaneous flap provides a valuable tool for repair of foot and ankle soft-tissue defects.

Accidents, Traffic↗
PubMed2004

Ultrastructural analysis of peripheral-nerve regeneration within a nerve conduit.

The purpose of this study was to observe the cellular components of regenerating peripheral nerves within a nerve conduit. Rat sciatic nerves were placed in a silicone conduit with a 5-mm gap between nerve endings. At weekly intervals for 6 weeks, 70-nm sections of nerve tissue from the conduit were obtained for ultrastructural observation. The principal cellular components by the end of the first week were macrophages and fibroblasts. By the end of the second week, both myelinated and unmyelinated nerve fibers began to pass through the entire conduit. By the end of the fifth week, nerve fibers were present at various levels of maturity, with no evidence of inflammatory or immunologic response. By the end of the sixth week, the percentage of nerve fibers was 86 percent of the cellular components. This analysis provides cellular data on which to base additional research regarding functional outcomes when using nerve conduits.

Animals↗
PubMed2004

Selective neurotization of the median nerve in the arm to treat brachial plexus palsy. An anatomic study and case report.

BACKGROUND: The current method for treatment of median nerve palsy after a brachial plexus injury is unpredictable. On the basis of an anatomic study of the median nerve in the arm, we present a new method of selective neurotization of the median nerve. METHODS: Internal topographic features of the fascicular groups of the median nerve were observed in seventeen cadavera. On the basis of the anatomical results, selective neurotization of the posterior fascicular group of the median nerve in the arm was performed in one patient with a complete brachial plexus palsy. RESULTS: In the distal half of the arm, the branches of the median nerve consistently collect into three fascicular groups, which are located at the anterior, middle, and posterior parts of the median nerve trunk. The anterior fascicular group is composed of the branches to the pronator teres and the flexor carpi radialis, the posterior fascicular group is composed mainly of the anterior interosseous nerve and the branches to the palmaris longus, and the middle fascicular group is made up mostly of the branches to the hand and the flexor digitorum superficialis. A transfer of the full length of the phrenic nerve was used to selectively reinnervate the posterior fascicular group of the median nerve in a patient with a complete brachial plexus palsy. The muscles supplied by the posterior fascicular group regained Grade-4 power, according to the system of the Medical Research Council, sixteen months after surgery. CONCLUSIONS AND CLINICAL RELEVANCE: The typical arrangement of the fascicular groups of the median nerve in the arm favors the technique of selective neurotization, which has been used effectively in one patient to date.

Adult↗
PubMed2003

Distally based radial forearm flap with preservation of the radial artery: anatomic, experimental, and clinical studies.

In this article we report on the anatomical, experimental, and clinical investigations of the distally adipofascial pedicled radial forearm flap based on the small perforators around the radial styloid process. There are about 10 small perforators (0.3-0.5 mm in diameter) from the distal radial artery around the radial styloid process. The longitudinal chain-linked vascular plexuses (suprafascial, paraneural, and perivenous) formed by the forearm ascending and descending branches of septofasciocutaneous perforators meet and cross over with the transverse carpal vascular plexuses around the radial styloid region. Based on these directional-oriented plexuses, distally based adipofascial pedicled radial forearm fasciocutaneous and adipofascial flaps were designed and successfully applied in 34 clinical cases. The pivot point was located at 1-2 cm above the radial styloid. The skin island plus adipofascial pedicle measured between 9-18 cm in length, with the adipofascial pedicle 3-4 cm in width. The length-to-width ratio is 3-5:1. The venous drainage of this distally based flap was investigated anatomically and experimentally. The cephalic vein has no positive role for venous drainage in distally based flaps. The difference between distally based flaps and reverse-flow flaps, clinical selection of fasciocutaneous and adipofascial flaps, advantages and disadvantages, and technical tips for operative success are discussed.

Adult↗
PubMed2003

Comparison of different managements of large superficial veins in distally based fasciocutaneous flaps with a veno-neuro-adipofascial pedicle: an experimental study using a rabbit model.

The role of large superficial veins in the survival of a distally based fasciocutaneous flap with a veno-neuro-adipofascial pedicle was studied in a rabbit model. A sural veno-neuro-fasciocutaneous flap model (6 x 2 cm) with a distally based lesser saphenous veno-neuro-adipofascial pedicle (1.5 cm) was established. Fifteen rabbits were randomly divided into three groups with 10 flaps in each group. In group I, the distal lesser saphenous vein was left open (venous inflow remained) after the flap was raised. In group II, the lesser saphenous vein was ligated in the pedicle (no venous inflow). In group III, the venous pedicle was left open in the pedicle, and the proximal end was microsurgically anastomosed to the recipient vein (outflow established). Intravenous pressure, flap survival, and histology were examined. The results showed that the values of intravenous pressure in group I were significantly higher than in group II (P < 0.001). The mean flap survival rate of group III (94.5%) was significantly higher (P < 0.001) than of groups I (22.7%) and II (55.5%). Histology showed that the lesser saphenous vein in group I was extremely dilated and filled with thrombosis. This experiment demonstrated that establishing a superficial venous outflow channel by anastomosis at the proximal end, or interrupting the inflow channel by ligation at the distal pedicle, may significantly improve the survival rate of distally based veno-neuro-fasciocutaneous flaps.

Animals↗
PubMed2003

Comparison of venous drainage in reverse-flow island flaps: an experimental study of the rabbit saphenous fasciocutaneous flap.

The mechanism of venous drainage in reverse-flow island flaps was investigated using the saphenous fasciocutaneous flap in New Zealand White rabbits. Ten animals were allocated into two groups of 10 flaps. In group I (left limb), the distal vascular pedicle (one saphenous artery and two venae comitantes) was not disturbed, maintaining the communicating and collateral branches intact. In group II (right limb), it was separated microsurgically from each other for 3 cm. Intravenous pressure was measured at 5, 15, 30, and 60 minutes after tourniquet release. The values of group II at 30 and 60 minutes were significantly lower (p<0.01) than those of group I. Ten days after flap elevation, the mean survival area of group I (95%) and group II (100%) was not significantly different. Histological examination of the vascular pedicle showed the saphenous veins in group II were more dilated than those of group I. These findings suggest that venous retrograde return in reverse-flow island flaps can be achieved more easily through a "direct incompetent valves route" than through a "circuitous communicating and collateral bypass route."

Animals↗
PubMed2002

Applying transfer of trapezius and/or latissimus dorsi with teres major for reconstruction of abduction and external rotation of the shoulder in obstetrical brachial plexus palsy.

To evaluate the effects of transfer of the trapezius and/or latissimus dorsi with the teres major for treatment of dysfunction of the shoulder in obstetrical brachial plexus palsy (OBPP), 34 patients with paresis of the abductors and external rotators, as well as co-contraction of the adductors in abduction, who had undergone reconstructive operations, were followed-up for at least 1 year. Of these, transfer of the latissimus dorsi with attached teres major to the insertion of the infraspinatus (single procedure), was performed in 25 cases, and transfer of both latissimus dorsi with teres major and trapezius (to the humerus) in nine (combined procedure). Gilbert's grading system was used for evaluation. The results showed that in spite of improvement of external rotation in most of the cases, abduction was improved in only 13 of the 25 cases with a single procedure, and that eight of nine cases with a combined procedure gained improvement of both external rotation and abduction. These results indicated that, for improvement of both abduction and external rotation of the shoulder in OBPP, transfer of the latissimus dorsi with the teres major can be performed only when abduction is > or =90 degrees; otherwise, transfer of the trapezius should be added.

Brachial Plexus Neuropathies↗
PubMed2002

Full-length phrenic nerve transfer by means of video-assisted thoracic surgery in treating brachial plexus avulsion injury.

Phrenic nerve transfer has been widely used in treating brachial plexus avulsion injury. However, the present method crosses the thoracic part of the phrenic nerve, and nerve graft is needed, resulting in a long period of regeneration and partly irreversible muscle atrophy. We present our early experience of using video-assisted thoracic surgery to harvest a full length of phrenic nerve for transfer. Fifteen patients (mean age, 28 years) were treated. The thoracic part of the phrenic nerve was freed by means of video-assisted thoracic surgery and taken out of the thoracic cavity, and a full-length phrenic nerve was transferred to the musculocutaneous nerve to recover elbow flexion. The patients were followed. Another 29 patients with long-term follow-up who underwent traditional cervical phrenic nerve to musculocutaneous nerve transfer in our institute between 1994 and 1997 were selected. The period of newborn potential appearing in the biceps and the period for biceps to achieve M3 between two groups were compared. The operation was safe and no complications occurred. The additional length of phrenic nerve was 12.3 +/- 4.5 cm. Eleven patients received sufficient follow-up. Eight patients achieved biceps recovery to M3 (elbow flexion against gravity), and mean time was 198.8 +/- 36.0 days, much earlier than that of the traditional method (p < 0.01). Pulmonary function recovered to the preoperative level 9 months after operation. This new method is safe and minimally invasive. The result of full-length phrenic nerve transfer is much better than that of the traditional method. It obviously shortens the time required for nerve reinnervation, and offers a promising method for patients who have had a long interval from injury to operation and for forearm muscle reconstruction by phrenic nerve transferred to the median nerve or combined with free-muscle transfer.

Adolescent↗