Biomedical subjects

Tien-Yow Chuang

Publications and source records attributed to Tien-Yow Chuang.

18 recordsLinked to original sources

PubMed2005

Treatment of complex subtrochanteric fracture with the long gamma AP locking nail: a prospective evaluation of 64 cases.

BACKGROUND: Complex subtrochanteric fractures are uncommon injuries and challenging to manage. We elucidate the role of the Long Gamma AP Locking Nail (LGAPN) in the management of such fractures in the acute stage. METHODS: Between 1992 and 2002, 64 consecutive cases with nonpathologic complex subtrochanteric fractures managed with the LGAPN were enrolled in this study. Associated injuries were present in 16 cases. The average follow-up period was 68 months. RESULTS: Mean time to union was 14 weeks. There were two complications (one wound infection and one delayed union). The time to union and functional results were not statistically different between different ages (below 50 years old, or older than 50 years) and the number of distal locking screws used (one or two). Longer time to union is noted in patients with a longer operation time and a more comminuted fracture pattern by the AO classification. CONCLUSION: Closed reduction and internal fixation with the LGAPN were proven to be safe and effective in the treatment of complex traumatic subtrochanteric fractures in all age groups, and one distal locking screw is sufficient for distal fixation.

Adult↗

PubMed2005

The results of open reduction and internal fixation in elderly patients with severe fractures of the distal humerus: a critical analysis of the results.

BACKGROUND: We would like to define the results of treatment of open reduction and internal fixation in elderly patients with severe fractures of the distal humerus. METHODS: Between 1988 and 1998, 19 consecutive aged patients (older than 65 years old) with displaced comminuted articular fractures of the distal humerus were treated by open reduction and internal fixation with AO reconstruction plate. The age at the time of injury was 71.9 (65-79) years old. According to the AO classification, 15 patients had type C2 and four had type C3 injury. No patient had inflammatory arthritis of the elbow. The period of follow up is 97.2 (60-174) months. RESULTS: All fractures united with union time of 14.6 (11-20) weeks. No implant failure was found. In final follow up, the average flexion contracture was 16.8 degrees with a range of 0-40 degrees , the average active flexion was 128.4 degrees with a range of 115-140 degrees , the average pronation was 80 degrees with a range of 60-90 degrees , and the average supination was 78 degrees with a range of 60-90 degrees . According to the elbow motion classification of Cassebaum, eight (42.1%) patients were graded as very good elbow motion, eight (42.1%) as good, three (15.8%) as fair, and none as poor. The functional results showed that 15 (79%) patients had excellent results, four (21%) had good results, and none had fair or poor results, according to Mayo elbow performance score. The radiographic evaluation in final follow up showed that four patients (21%) had no osteoarthritic (OA) change, 11 (58%) had grade 1 OA, four (21%) had grade 2 OA, and none had grade 3 OA (the scale of Knirk and Jupiter). Fifteen (79%) patients reported no pain and four (21%) had mild pain. All patients were satisfied with their results. However, There were two early post-operative complications, including one (5.3%) superficial wound infection and one (5.3%) iatrogenic ulnar nerve injury. CONCLUSIONS: Open reduction and internal fixation with appropriate surgical technique is effective in the treatment of displaced fractures of the distal humerus in elderly patients.

Aged↗

PubMed2004

Spinal cord repair with acidic fibroblast growth factor as a treatment for a patient with chronic paraplegia.

STUDY DESIGN: We present a case of a patient with chronic paraplegia with a complete spinal cord gap resulting from a stabbing injury 4 years ago recovering after an innovative surgical strategy. OBJECTIVES: To demonstrate the clinical outcome of surgical repair with sural nerve graft with fibrin glue containing acidic fibroblast growth factor in a patient with chronic spinal cord injury. SUMMARY OF BACKGROUND DATA: Spinal cord injury usually causes permanent disability, and there had been not effective surgical technique to obtain satisfactory functional motor recovery, particularly in chronic patients. Previous studies have revealed that acidic fibroblast growth factor could promote axonal regeneration and reduce neuronal death in adult rats with spinal cord injury. METHODS: The spinal cord gap at T11 level was bridged with 4 sural nerve grafts that redirected specific pathways from white to gray matter. The grafted area was stabilized with fibrin glue containing acidic fibroblast growth factor. RESULTS: Before the operation, the paraplegia was identified as ASIA-C, with a motor score for the right and left legs of 12 and 0, respectively, a pinprick score of 77, and 77 on a light touch of left side limbs. His functional status improved from being wheelchair-bound to being able to ambulate independently with a walker 2-and-a-half years after surgery. At this stage, paraplegia was ASIA-D, with motor scores for the right and left legs of 15 and 12, respectively, 86 for a pinprick, and 86 for a light touch of left side limbs. CONCLUSIONS: This case demonstrated significant motor recovery attained in a patient with chronic paraplegia following a repair surgery with nerve graft and growth factor.

Adult↗

PubMed2004

Acidic FGF enhances functional regeneration of adult dorsal roots.

It has been well documented that the regeneration of sensory axons severed in the dorsal roots into the spinal cord is largely inhibited in adult mammals. We investigated whether peripheral nerve grafts combined with acidic fibroblast growth factor (aFGF) could induce the regeneration of transected dorsal roots in adult rats, as evaluated by cortical somatosensory evoked potentials (SEPs). Median nerve (forelimb) stimuli produced consistent responses in the primary somatosensory cortex of normal rats, but these were completely eliminated after the transection of cervical 6th - 8th roots. The dorsal root stumps were immediately anastomosed to the cord with intercostal nerve grafts. Subsequently, aFGF in fibrin glue was administered to the grafted area. Four to twenty weeks after rhizotomy, six of the seven rats receiving such reconstruction had recovery of SEPs. The reappearing SEPs typically showed similar waveforms and latencies as normal ones. They were eliminated by retransection of the repaired roots, thus verifying their source as the regenerated roots. We present here substantial evidence that aFGF enhances the functional restoration of cut dorsal roots. Cortical SEPs is considered a useful tool in evaluating such regeneration. These results may offer therapeutic potential in the treatment of dorsal root injuries.

Analysis of Variance↗

PubMed2004

Repair of multiple cervical root avulsion with sural nerve graft.

To obtain easier access to avulsed roots in the intradural space for patients suffering cervical root avulsion, the authors of this study developed a novel repair method. This involves using nerve grafts to bridge corresponding segments of the spinal cord and the trunk or cord level of the plexus, respectively, in two surgical stages. All eight patients admitted to this study received pre- and post-operative workups of electrophysiological evaluations and muscle power grading through Medical Research Council (MRC) scores. The degrees of impairment were also graded according to a modified version of Dumitru's and Wilbourn's scale (mild = 1; moderate = 2; severe = 3). The preoperative versus post-operative differences in the severity of the injuries and in the grading of the target muscle power were calculated according to the Wilcoxon signed-rank test. The preoperative degree of the severity of the injuries, as measured by electromyography (EMG), was 3.00 +/- 0.00 (mean +/- S.D.). The post-operative result was 2.125 +/- 0.641. Significant change took place after repair (P = 0.0313). Moreover, although little improvement was observed in the triceps, brachioradialis (BR), extensor carpi radialis (ECR), flexor digitorum profundus (FDP) and intrinsic hand muscles, the MRC grading showed significant yet not prominent motor recovery in the deltoid and biceps brachii (both P = 0.0313). We were impressed that the initial significant statistical results of differences in pre- and post-operative severity of the injuries and muscle power grading, demonstrated that regeneration does occur with this repair strategy.

Accidents, Traffic↗

PubMed2004

Surgical treatment of acute displaced fractures of adult distal humerus with reconstruction plate.

We evaluated the results of the use of AO reconstruction plates in the open reduction and internal fixation of acute displaced fractures of the adult distal humerus. This was a retrospective study of such patients where the main surgical strategy was open reduction and internal fixation with AO reconstruction plates. From 1992 to 1998, 40 patients were included. Average follow-up was 98 (60-127) months. All the fractures united with the union time of 11.7 (9-16) weeks. Early post-operative complications developed in four patients (10%), including wound infection in two (5%) and iatrogenic ulnar neuropathy in another two (5%). At follow-up, 24 (60%) patients developed grade 1 osteoarthritis and eight (20%) developed grade 2 osteoarthritis. Thirty-five patients (87.5%) got good to excellent functional results and 35 cases (87.5%) were satisfied with their surgical results. In conclusion, open reduction and internal fixation with AO reconstruction plate is very useful and effective in the treatment of displaced fractures of the adult distal humerus.

Adolescent↗

PubMed2004

Loss of sympathetic coordination appears to delay gastrointestinal transit in patients with spinal cord injury.

Patients with spinal cord injury (SCI) often suffer from many gastrointestinal (GI) complaints, while delayed GI transit exists in these patients. We are interested in whether the lost sympathetic activity is one of the mechanisms leading to disturbed GI transit in these subjects. Using a noninvasive hydrogen breath test representing orocecal transit time (OCTT) to study GI transit, 36 SCI patients and 12 age- and sex-matched healthy volunteers were enrolled in our study. Meanwhile, electrocardiogram was performed for all subjects. Finally, spectral analysis of heart rate variability (HRV) was then obtained to assess their sympathovagal balance. SCI patients had higher occurrences of GI symptoms, e.g., nausea/vomiting, belching/hiccup, and constipation, compared to controls (P < 0.05). OCTT was delayed in SCI patients compared to controls (180.8 +/- 10.7 vs 98.3 +/- 14.4 min; P < 0.001). The OCTTs of SCI patients were negatively correlated with their low frequencies of HRV (r = -0.384, P = 0.021). In addition, OCTT was further delayed in quadriplegic patients than paraplegic patients (195.8 +/- 14.5 vs 143.6 +/- 19.4 min; P = 0.031). However, neither the SCI etiology, the injury duration, nor the high frequency of HRV had any influence on the delayed OCTT in SCI patients. We conclude that the GI transit of SCI patients is delayed. This transit disturbance is probably due to loss of sympathetic activity, which is one of the essential components in the coordination of GI peristalsis.

Adult↗

PubMed2004

Transacromial Knowles pin in the treatment of Neer type 2 distal clavicle fracturesA prospective evaluation of 32 cases.

BACKGROUND: The high rate of non-union makes surgical intervention necessary for a distal clavicle fracture. This report presents the outcome of a simple surgical method using a transacrominal Knowles pin for this unstable fracture. METHODS: In this study, 32 patients with Neer type 2 distal clavicle fractures were treated using a single transacromial Knowles pin without repair of the torn ligament. All 32 patients were studied prospectively and followed up for a mean of 80 months (range, 12-132 months). The clinical outcome was evaluated with the UCLA score, and the fracture union was judged roentgenographically. RESULTS: All the patients showed excellent results with solid union. The mean union time was 6.8 weeks (range, 4-12 weeks). No major complication was noted, and only one asymptomatic acromioclavicular arthrosis developed. CONCLUSIONS: Single transacrominal Knowles pin fixation offers a simple and safe method for treating patients with displaced Neer type 2 distal clavicle fractures.

Accidental Falls↗

PubMed2004

Treatment of unstable pelvic fractures: use of a transiliac sacral rod for posterior lesions and an external fixator for anterior lesions.

BACKGROUND: This study sought to define the role of transiliac sacral rods used in combination with an external fixator for the management of unstable pelvic fractures. METHODS: This retrospective study evaluated cases in which the surgical strategy was open reduction and internal fixation of posterior lesions with two transiliac sacral rods and closed reduction and external fixation of anterior lesions with an AO external fixator. The data for 65 cases were analyzed. Comprehensive Classification (AO) identified 42 C1 cases, 21 C2, cases and 2 C3 cases. Fractures with iliac bone involvement that impeded the application of an external fixator or transiliac sacral rods were excluded. The follow-up period was 85 months (range, 24-140 months). RESULTS: All the fractures/dislocations healed well. The complications involved 17 cases (26.2%) of persistent posterior pain, 16 cases (24.6%) of irreversible neurologic deficit, 2 cases (3.1%) of posterior wound infection, 3 cases (4.6%) of pin tract infection, and 4 cases (6.2%) of irreversible urologic deficit. The functional results showed that the surgical results were satisfactory in 42 cases (64.6%) and unsatisfactory in 23 cases (35.4%). CONCLUSIONS: For type C pelvic fractures without significant iliac bone involvement, surgical management with posterior transiliac fixation using sacral rods and anterior external fixation yields good radiologic results. The functional results correlated primarily with avoidance of complications and not necessarily with the radiologic results.

Adolescent↗

PubMed2004

The challenge of diagnosing psoas abscess.

Diagnosing psoas abscess in patients with low back pain might be hampered by their atypical symptoms. We describe a case in which a 39-year-old retired provost marshal presented to our emergency facility with acute onset of low back pain following an episode of lumbar strain during a flight. His initial computed tomography of lumbar spine and abdominal sonography were inconclusive. Two weeks later, he was admitted to our rehabilitation unit for similar symptoms. One day later, leukocytosis and elevated c-reactive protein following rising body temperature were found. Fever of unknown origin (FUO) was impressed after series of laboratory studies. However, an inflammatory gallium scan performed 2 weeks later due to persistent fever revealed active infection in the L4 vertebra and soft tissue of the L5 paraspinal region. MRI was then performed and demonstrated abnormal enhancement at the bodies of the L2 and L3 vertebrae, prevertebral soft tissue and bilateral psoas muscles. A CT-guided percutaneous aspiration of 10 cc yellowish pus was attained, which yielded no pathogens. His symptoms subsided 1 week after being given appropriate antibiotics. This case showed the importance of nuclear scanning and MRI in patients with low back pain and FUO. It also suggests that repeated imaging study and/or other modality should be considered when the initial imaging result is not compatible with the clinical presentation of psoas abscess, which was initially missed by image studies.

Adult↗

PubMed2003

Cervical root repair in adult rats after transection: recovery of forelimb motor function.

Functional recovery was achieved in rats after repairing the transected left sixth and seventh cervical roots. Intercostal nerves were used for reanastomosis between the transected roots and the spinal cord, and acidic fibroblast growth factor with fibrin glue was applied. Experimental rats showed relevant functional recovery of gait and grooming reflexes. Electromyography demonstrated less denervation and more regeneration. Horseradish peroxidase retrograde axonal tracing disclosed a statistically significant increase of motor neuron survival, suggesting that motor neuron survival was significantly correlated with functional recovery. It is our belief that this novel treatment strategy may help patients with similar injuries in the future.

Animals↗

PubMed2003

Neurourological changes before and after radical hysterectomy in patients with cervical cancer.

BACKGROUND: The severity of bladder dysfunction in patients receiving radical hysterectomy for cervical cancer has been related to the delicacy and the degree of radicality of the hysterectomy. Our goal was to evaluate the effect of modified radical hysterectomy on the storage and evacuation of the lower urinary tract. METHODS: In this prospective study, 18 patients underwent radical hysterectomy for cervical cancer with FIGO stages Ia, Ib and IIa. These patients participated in a pudendal motor nerve conduction study and a urodynamic study, including urethral pressure profile (UPP), cystometry (CMG) and uroflowmetry (UFR). These were carried out at preoperative baseline and at 2 weeks, 6 weeks, 3 months and 6 months following surgery. We used generalized linear models to evaluate, over time, the relationship between the different parameters marked in these profiles. RESULTS: The average pudendal nerve motor latency was prolonged at 2 and 6 weeks after surgery but recovered to baseline at 3 months postsurgery. Maximal urethral closing pressure revealed a tendency to decrease, and the CMG showed a significant increase in maximum intravesical filling pressure and a marked decrease in compliance throughout the investigative course. Increased residual urine volume and decreased uroflow rates were detected in a series of UFR. However, these values headed for baseline at 6 months after surgery. CONCLUSION: Transient neurological changes in the majority of our patients suggested that both somatic and autonomic demyelination with or without denervation might be responsible for the temporal changes in vesicourethral function after radical hysterectomy and recovery to baseline condition within 6 months.

Adult↗

PubMed2003

Acute urinary retention after use of assisted reproductive technology. A report of 2 cases.

BACKGROUND: Urinary retention in women is an unusual occurrence. Various conditions can cause it, including surgery, childbirth, pelvic masses, procidentia, vulva hematoma, incarceration of a gravid uterus, urologic disease, neurogenic disease and psychiatric disorders. CASES: Two infertile women underwent assisted reproductive technology (ART) and luteal-phase support during which acute urinary retention occurred. The patients were evaluated by means of physical examination, urodynamic study and determination of serum progesterone levels. Bladder distention was found during luteal-phase support. Urodynamic studies revealed detrusor areflexia. Serial serum progesterone levels were > 100 ng/mL. CONCLUSION: Cases of acute urine retention during luteal-phase support are rarely reported. Urine retention should be considered in the differential diagnosis when abdominal pain occurs after patients undergo ART. Transient elevation of the progesterone level may be the cause of the acute urine retention.

Acute Disease↗

PubMed2003

Injuries during a massive tug-of-war game.

"Tug-of-war" may cause a variety of sports injuries, which has rarely been reported previously. This report described an uncommon case of a previously fit 64-year-old male who presented with abrupt onset of loss of consciousness after falling down in a game of massive tug of war including 1,500 participants as the rope snapped apart. Computed tomography (CT) scan of his abdomen revealed liver and spleen rupture. Spinal cord injury due to traumatic herniation of intervertebral disc at C5-6 level and bilateral brachial plexus injury were also noted after exploratory laparotomy with primary repair of liver and spleen. He then received diskectomy over C5-6 and C6-7 and neurolysis for the right brachial plexus. Multiple neurological complications including paraplegia, severe neuralgia over bilateral C5 dermatome and spasticity over bilateral lower extremities developed. After two-year comprehensive rehabilitation programs, the patient recovered to ambulate with assistive device, and resumed partially dependent daily living activities.

Athletic Injuries↗

PubMed2002

Forelimb muscle activity following nerve graft repair of ventral roots in the rat cervical spinal cord.

Current research on the cellular mechanisms of nerve regeneration suggests the application of nerve growth factors at the repair sites to be beneficial. To test the effectiveness of this approach, we performed transections of the C6 and C7 ventral rootlets from their original sites in the spinal cord of 18 rats. We investigated the electrophysiological changes in three groups of rats operated on by different repair strategies. Six rats comprised the control group (G1). In the other 12 rats, 24 rootlets were implanted into the spinal cord by means of an intercostal nerve graft through the pia mater immediately after transection. Six rats (G2) had fibrin glue applied at the incision. The last 6 rats (G3) had grafts with acidic fibroblast growth factor (aFGF) added to the fibrin glue. The rats' functional recovery was evaluated electrophysiologically at 6 weeks and 6 months after the operation. Needle electromyography showed profound fibrillation potentials (Daube's scoring system) in the deltoid, biceps, and triceps of the operated forelimbs in all groups 6 weeks after the operation. After 6 months, there was a significant decrease in the amount of fibrillation potentials in all groups (G1, G2 and G3, p < 0.0001, 0.0001, 0.0009, respectively, generalized estimating equation, repeated measures) and a significantly high probability for motor units present in sampled muscles of G2 and G3 as compared to G1 (log odds ratio in G2 = 51.8316, G3 = 57.4262, generalized estimating equation). We conclude that several cervical roots can regenerate through intercostal nerve grafts applied using fibrin glue. Adding aFGF may increase the efficacy of sprouting.

Animals↗

PubMed2002

Electrophysiologic findings and muscle strength grading in brachioplexopathies.

The electrophysiological evaluations and the British Medical Research Council (MRC) scale (0-5) findings of target muscles in brachioplexopathies before surgery and 1 year postsurgery were conducted. Each component of the brachial plexus was analyzed in 15 patients with injuries, among them, to 5 roots, 19 trunks, 7 cords, and 13 terminal nerves. In each of these cases, neurolysis and/or nerve transfer and/or neurotization were performed, within 3 weeks to 6 months after the injury was incurred, to ameliorate the resulting severe disabilities. The degrees of impairment were graded using a modified version of Dumitru's and Wilbourn's scale (mild: normal to slight decrease of SNAP amplitude and CMAP amplitude, and occasional denervation; moderate: profound decrease of SNAP amplitude and CMAP amplitude, constant denervation, and normal to slight decrease in motor unit recruitment; severe: absent SNAP amplitude, absent CMAP amplitude, marked denervation, and profound decrease or no volitional motor unit recruitment. mild = 1; moderate = 2; severe = 3). The motor power of the target muscles was graded through MRC scores. The presurgical versus postsurgical differences in the severity of the injury to each brachial plexus component, and differences in the grading of target muscle power, were calculated through the Wilcoxon signed-rank test. The presurgical degrees of the severity of injury, as measured by the electromyography (EMG) were 3.00 +/- 0.00 (mean +/- SD) in root, 2.84 +/- 0.50 in trunk, 3.00 +/- 0.00 in cord, and 2.85 +/- 0.38 in terminal nerves. The postsurgical results were 2.60 +/- 0.55 in root, 2.53 +/- 0.70 in trunk, 2.43 +/- 0.53 in cord, and 1.77 +/- 0.73 in terminal nerves. There was significant improvement at the trunk, cord, and terminal nerve levels after repair, but not at the root levels. Moreover, although the MRC grading showed significant motor recovery in the infraspinatus, deltoid, biceps, and triceps muscles, there was little apparent improvement in the pectoralis major, EDC, APB, and ADM muscles. Nerve repair was notably successful in all plexuses except at the root level. However, our cases demonstrated only poor motor power gains in the forearm and the hand muscles. Consequently, future surgical techniques for brachioplexopathy repairs need further improvement.

Adolescent↗

PubMed2002

The comparison of electrophysiologic findings of traumatic brachial plexopathies in a tertiary care center.

This study was undertaken to demonstrate the distribution of causative factors of brachial plexopathy (BP), to assess the association between the mechanism of injuries and the predominant level of the brachial plexus involved in the injuries, and to characterize the extent and degree of severity of injury in patients with BPI. It consisted of a cross-sectional, retrospective review of electrophysiological data of 5547 patients with 117 patients being identified as having BPI, of whom 86 patients were recruited into the study. The patients were divided into six subgroups according to the mechanism of the damage. The injury was subdivided according to the brachial plexus levels predominantly affected, and each component of the four major anatomical plexus levels-root, trunk, cord and nerve levels was analyzed. The affiliation between the type of injuries and the specified brachial plexus levels was calculated via a two-tailed Fisher's exact test. These findings demonstrated that the type of brachial plexus injury (BPI) is significantly related to the brachial plexus level involved. The motorcycle and birth injury groups were affected at the trunk level, the fall group at the nerve level, the automobile group at the cord level, and the blunt injury group at the cord or nerve level. Moreover, the majority of patients in the motorcycle, fall, and pedestrian groups suffered from severe, incomplete lesions, while the neurophysiological results of the other groups varied.

Accidents, Traffic↗

PubMed2002

A virtual reality-based system for hand function analysis.

The goal of this study was to demonstrate the usability and usefulness of virtual reality technology in assessing hand functions. Ten healthy, non-disabled right-handed adult volunteers were recruited. Each volunteer used a dataglove to insert three-dimensional virtual representations of a cylinder and a prism into the target holes. To verify the reliability of the tests, each subject was retested twice. The performance testing assessed the visual-motor coordination a person needs to achieve a task accurately and within a set time. For each trial, the root mean square (RMS) value of the hand movement trajectory was projected onto the X, Y, and Z axes. This projection enabled us to measure the extent of the genuine, summative displacement of the manipulating hand. The reproducibility of the virtual reality assessment was analyzed using the intraclass correlation (ICC) approach. The total ICC values of 10 subjects demonstrated a high task completion time and RMS on the X and Z axes for the transferring of the prism. However, the values were low for the transferring of the cylinder. Because the individual coefficients of variations (CVs) varied widely in the moving of both the cylinder and the prism, the total (CVs) showed a high reading for the task completion time. Although rehabilitation clinics routinely carry out peg-moving exercises for disabled patients, our model provides a valuable quantitative real time and off-line measure of whole hand functions.

Adult↗