Biomedical subjects

H T Hee

Publications and source records attributed to H T Hee.

14 recordsLinked to original sources

PubMed2005

Pyogenic vertebral osteomyelitis: a review of 14 cases.

PURPOSE: To review and evaluate the management of 14 patients with pyogenic vertebral osteomyelitis at National University Hospital, Singapore between 1998 and 2001. METHODS: Demographic pattern, predisposing factors, clinical presentation, co-morbidities, microbiology, treatment, and complications of 14 patients were retrospectively reviewed. RESULTS: The mean age at presentation was 62.5 years and the male to female ratio was 6:1. The mean follow-up duration was 12.5 months. The most common predisposing condition was diabetes mellitus (n=5). The most common site of infection was the lumbar spine (n=8), followed by the thoracic (n=4) and cervical (n=2) spine. Staphylococcus aureus was the most common causative organism isolated (n=9), followed by methicillin-resistant S aureus (n=3), Pseudomonas pseudomallei (n=1), and Streptococcus agalactiae (n=1). 12 patients were treated surgically: 8 by an anterior approach, 3 by a posterior approach, and one by a combination of the 2. The mean period of antibiotic use was 11.4 weeks. One patient with melioidosis involving the T9 to T11 vertebrae caused by P pseudomallei died of empyema and septicaemia 22 months after presentation. CONCLUSION: Pyogenic vertebral osteomyelitis is not uncommon in the elderly, especially those with predisposing conditions such as diabetes mellitus. Computed tomography-guided needle biopsy is recommended to investigate causative microorganisms. Aggressive surgical debridement and prolonged antibiotic therapy were necessary in patients with methicillin-resistant S aureus, P pseudomallei, and S agalactiae.

Adult↗

PubMed2003

Gait adaptations in patients with longstanding hip fusion.

PURPOSE: To examine the long-term effects of hip arthrodesis in terms of gait adaptations. METHODS: Motion analysis was performed on 9 patients who underwent unilateral hip arthrodesis between 1979 and 1991. A standard clinical gait analysis 3-dimensional model for the lower limb was used to calculate the effect of the fused hip on walking, compared with the contralateral normal hip. RESULTS: Significant (p<0.05) gait adaptations noted in the fused side were, compensatory hip hiking during the swing-phase, a 24% reduction in hip adduction moment, a 37% decrease in genu-varus moment, 80% reduced hip power, and excessive pelvic tilt. CONCLUSION: It appears that the excess pelvic tilt observed was to achieve relative hip extension via increased relative lumbar lordosis, while the decreased coronal plane moments of the hip and knee observed were to reduce joint loading on the affected side.

Adaptation, Physiological↗

PubMed2003

The long-term results of surgical treatment for spinal stenosis in the elderly.

PURPOSE: To evaluate the surgical results of spinal stenosis in the elderly and to investigate which factors may contribute to a poor outcome. METHODS: This is a retrospective study of 68 patients aged 60 and above who had decompression laminectomy for lumbar spinal stenosis between 1989 and 1991. They were evaluated at an average of eight years after surgery. The mean age at surgery was 68 years. Twenty-eight had co-existing illnesses. Twenty-one had concomitant degenerative spondylolisthesis. Thirty-two (47%) had decompression laminectomy performed at one level. Eleven (16%) had arthrodesis. Seven had spinal instrumentation, of which six were Hartshill rectangles. Functional result was graded using modified Paine classification. Multivariate analysis with logistic and linear regression was used to determine predictors of poorer outcomes. FINDINGS: There were 68% excellent and good, 22% fair and 10% poor results. Back pain was relieved in 91% of the patients. Leg pain was relieved in 76% of the patients. Numbness was relieved in 87% of the patients. Five patients had re-operations. Multivariate analysis revealed that age, sex, co-morbidity score, number of levels decompressed, and degenerative spondylolisthesis did not predict worse outcomes. However, Hartshill rectangle instrumentation and pre-operative leg numbness predicted less favourable results. CONCLUSIONS: The surgical results of spinal stenosis in the elderly are favourable and comparable to those reported for the general population at an eight-year follow-up.

Aged↗

PubMed2002

A case report of neurologically unstable fracture of the lumbosacral spine in a patient with ankylosing spondylitis.

INTRODUCTION: Fracture/dislocation is uncommonly reported in ankylosing spondylitis involving the lumbosacral spine. CLINICAL PICTURE: We report an 18-month follow-up of a case of neurologically unstable traumatic fracture of the lumbosacral spine in ankylosing spondylitis. TREATMENT/OUTCOME: Posterior decompression, alar-transverse fusion and instrumentation were performed. Anterior diskectomy and fusion were done 6 weeks later. There was solid bony fusion on follow-up and the patient had improvement of 2 Frankel grades and was able to ambulate. CONCLUSION: Combined approaches and longer fixations to stabilise the spine may be required. In the lumbosacral spine, this poses a problem vis-à-vis limited levels of fixation in the sacrum.

Accidental Falls↗

PubMed2002

Instrumentation in spinal surgery.

As a result of rapid advances in the field of spinal instrumentation, the surgeon today has at his disposal many well-designed implants, such as pedicle screws, hooks, rods, plates, and interbody fusion devices. Many of these implants are modular and are used in combination, such as hooks and screws attached to rods, allowing the surgeon flexibility in selecting the appropriate implants to meet the particular needs of the patient. Spinal instrumentation restores or enhances the mechanical stability of the spine, corrects and maintains spinal alignment, and enhances spinal fusion. The disadvantages associated with the use of instrumentation include increases in cost, operative time, infection rate, re-operation rate, and a steep learning curve. As spinal instrumentation is evolving constantly, it is important to understand the surgical indications and principles of its use. Being highly trained and familiar with the use of these implants is the only sure way to avoid the potentially serious complications that have been associated with their use.

Bone Screws↗

PubMed2001

Predictors of outcome of floating knee injuries in adults: 89 patients followed for 2-12 years.

Of the 98 floating knee injuries that were consecutively treated from 1987 to 1997, 89 patients were available for analysis. There were 80 males and 9 females, ranging from 15 to 70 years old. Average follow-up was 5 (2-12) years. Injury severity scores ranged from 18 to 45. 21 fractures were intra-articular. 55 fractures were open. Substantial comminuted and segmental fractures occurred in 57 cases and 35 cases, respectively. Multivariate analysis showed that increasing age was associated with delays in bony union and full weight bearing ability. An increase in the number of pack years smoked at the time of injury predicted the likelihood of knee stiffness, delays in bony union and full weight bearing ability. Higher injury severity scores were associated with delayed full weight bearing ability. The presence of open fractures predicted the likelihood of knee stiffness and delayed full weight bearing ability. Comminuted fractures were associated with malunion, and segmental fractures with delayed bony union. Using the outcome of floating knee injuries as fair or poor, according to Karlström and Olerud's criteria, we constructed a preoperative prognostic scoring scale which showed a sensitivity of 0.72 and a specificity of 0.90.

Activities of Daily Living↗

PubMed2001

Anterior/posterior lumbar fusion versus transforaminal lumbar interbody fusion: analysis of complications and predictive factors.

No previous study has compared the complications between anterior/posterior and transforaminal interbody fusions. We performed a retrospective analysis of 164 patients to compare the complications and associated predictive factors of the two techniques of circumferential lumbar fusion. Fifty-three had same-day anterior/posterior fusion (group 1), and 111 had transforaminal interbody fusion (group 2). Mean operating time (p < 0.0001) and hospital stay (p < 0.0001) was significantly longer for group 1 patients. Average blood loss was greater for group 1 patients (p < 0.01). Higher complication rates were found in group 1 patients (p < 0.004). Wound infection occurred more frequently in patients with adjunctive treatment (p < 0.04). Hospital stay was an independent predictor of complications in both groups. In group 1, body mass index was independently associated with complications. In group 2, both hospital stay and adjunctive treatment were predictive of complications. Transforaminal lumbar interbody fusion is the preferred technique because it is associated with shorter operating time, less blood loss, shorter hospital stay, and lower incidence of complications.

Adult↗

PubMed2000

Surgical results of intercondylar fractures of the adult femur.

INTRODUCTION: Although surgical treatment of intercondylar fractures of the adult femur gives satisfactory results in the majority of cases, there are complications reported with operative management. We aim to analyse the surgical results of these cases performed in our institution and compare them to other reported series. MATERIALS AND METHODS: A total of 16 patients with intercondylar fractures of the femur were operatively treated from 1989 to 1997. The ages of these patients ranged from 24 to 77 years, with a mean age of 42 years. Average length of follow-up was 28 months. The fractures were classified according to AO classification. Twenty-five per cent of the fractures were significantly comminuted. They were internally fixed with various implants such as cancellous screw fixation, dynamic condylar screw plate, condylar blade plate and condylar buttress plate. RESULTS: Average time to full weight bearing was 12 weeks. Results of treatment were assessed according to the criteria described by Shelbourne. Eighty-three per cent of minimally comminuted fractures had a good result, but only 50% of significantly comminuted fractures did well. CONCLUSIONS: We recommend the use of anterior midline approach and condylar buttress plate for very comminuted fractures. Infection, if detected early and treated aggressively could avoid a poor outcome. Elderly patients should benefit from internal fixation and earlier mobilisation.

Adult↗

PubMed1999

Transscaphoid perilunate fracture/dislocations--results of surgical treatment.

Sixteen cases of dorsal transscaphoid perilunate fracture/dislocations in 15 patients were treated by open reduction and internal fixation of the scaphoid with a Herbert screw and/or Kirschner wires. All patients were male, with a mean age of 31 years. The average follow-up period was 3 years. These perilunate dislocations were transscaphoid in 13 cases, and transstyloid and transscaphoid in 3 cases. There was one case of median nerve deficit preoperatively. Open reduction was performed through a volar approach in all cases. Herbert screw fixation of the scaphoid was performed on 13 cases, of which supplemental Kirschner wires were used in 2 cases. Three cases had fixation with Kirschner wires only. There were 2 cases of non-union which required bone grafting on follow-up. A clinical evaluation scoring system assessing pain, occupational ability, range of motion and grip strength was used. Based on this, there were 10 excellent to good (62.5%) and 6 fair results. For the majority of our patients, surgical outcome is characterised by acceptable relief of pain, functional motion and grip strength.

Adult↗

PubMed1998

Surgical results of open reduction and plating of humeral shaft fractures.

Thirty-five patients who sustained humeral shaft fractures were treated by open reduction internal fixation using AO techniques between 1992 and 1997. Open fractures occurred in 8 patients. Primary radial nerve palsy was present in 5 cases. In 16 patients an open fracture or multiple trauma, or both were indications for surgery. Eight osteosynthesis were performed after failed conservative treatment. The complications encountered were non-union (2 cases), osteomyelitis (2 cases), secondary radial nerve palsy (3 cases) and repeat surgery (4 cases). Bony union averaged 5.3 months radiographically. All cases of radial nerve palsy recovered eventually. Twenty-seven patients reported no pain. Twenty-six patients had full range of motion in the shoulder and elbow. Thirty-three patients had full muscle strength. Open reduction internal fixation gives good results provided correct indications and principles of fixation are adhered, and is a good alternative to conservative treatment. We advocate operative reduction internal fixation and nerve exploration in fractures associated with radial nerve palsy.

Adolescent↗

PubMed1996

Comparing staple fixation to buttress plate fixation in high tibial osteotomy.

A retrospective study was made between July 1988 and March 1992, of 171 patients (223 knees) who had high tibial osteotomy at the Singapore General Hospital. Seventy-four cases (97 knees) had buttress plate fixation and 97 cases (126 knees) had staple fixation. The mean postoperative Hospital for Special Surgery Knee Score was 87.0 for the buttress plate group and 87.4 for the staple group. The difference was statistically not significant (P > 0.05). The hospitalisation stay was shorter in the staple fixation group as compared to the buttress plate group (P < 0.05). However, the mean rehabilitation time was shorter in the buttress plate group as compared to the staple fixation group (P < 0.05). The incidence of wound infection was higher among those fixed with buttress plate (9 cases) as compared to those fixed with staple (1 case). The difference was statistically significant (P < 0.05). Buttress plate fixation did not seem to eliminate the risk of non-union of the osteotomy (4 out of 126 osteotomies compared to 3 out of 97 in the staple group), neither did it prevent recurrence of varus deformity (2 out of 126 osteotomies). Overall it would appear that buttress plating did not have any significant advantage over staple fixation for high tibial osteotomy.

Female↗

PubMedDate not supplied

Gait and pedobarographic patterns of surgically treated clubfeet.

Gait analysis and pedobarography were done on 58 surgically corrected clubfeet in 40 children. The average age of patients at the time of surgery was 6.7 months. The average age of the children at the time of the gait analysis was 6.1 years. Twenty-two children (32 feet) were 5 years old and younger. Eighteen children (26 feet) were older than 5 years old. Cadence, velocity, duration of single-limb stance, step length, and ground reaction force measurements were not significantly different from normal children. Differences noted in clubfeet were: 1) duration of single-limb stance among bilateral clubfeet did not increase with age; 2) increased ankle plantarflexion between opposite foot-strike and toe-off was not present; 3) the feet were internally rotated throughout (toe-in gait); 4) anterior and lateral ground reaction force measurements revealed differing trends with age; and 5) mid- and forefoot pressures increased in the surgically treated group. Gait analysis and pedobarography could detect more subtle abnormalities in corrected clubfeet and provide more objective assessments of persistent deformities.

Child↗

PubMedDate not supplied

SF-36 health status of workers compensation cases with spinal disorders.

BACKGROUND CONTEXT: Poorer outcomes of treatment are reported in patients with spinal disorders who receive workers compensation. The reason for their suboptimal outcomes is unclear. No study has examined the relationship between workers compensation and the Short Form Health Survey (SF-36) health status of patients with spinal disorders. PURPOSE: To compare the self-perceived health status of spinal disorder patients receiving workers compensation with those not receiving workers compensation. STUDY DESIGN/SETTING: A cross-sectional study on 18,389 patients who were evaluated in the 28 centers comprising the National Spine Network. PATIENT SAMPLE: The study data were derived from patients when first evaluated for back or neck pain between January 1998 and April 2000. OUTCOME MEASURES: The outcome measures used were the eight individual and two component scores of the SF-36. METHODS: All first-visit patients enrolled in the National Spine Network from January 1998 to April 2000 were reviewed. Eight individual scores and two component scores of the SF-36 were compared. RESULTS: Of the 18,389 patients, 1,535 (8%) were receiving workers compensation. Bivariate analyses showed all eight individual scores, and two summary scores of the SF-36 were significantly lower (p<.0001) in patients receiving workers compensation. After controlling for confounding covariates, workers compensation status was a significant predictor of lower SF-36 scores for General Health (p<.0001), Physical Functioning (p<.0001), Role Physical (p<.01), Social Functioning (p<.05), and Mental Health (p<.05). CONCLUSIONS: Workers compensation status is associated with poorer physical and mental health of patients with spinal disorders. Because the workers compensation group is younger, has a shorter duration of symptoms, and fewer comorbid medical problems, the lower SF-36 scores most likely reflect psychological factors and not ill health per se. The lower SF-36 scores may also reflect premorbid personality differences in the workers compensation patients, compared with those not receiving workers compensation. SF-36 is a validated tool that can be used to objectively identify the patient at risk for delayed recovery. Future treatment protocols should pay special attention to improve the health-related quality of life, especially general health and physical functioning of spinal patients receiving workers compensation.

Adult↗

PubMedDate not supplied

Significance of the lateral epiphysis of the acetabulum to hip joint stability.

Normal development of the acetabulum is crucial to the growth and stability of the hip. Twenty-five New Zealand White rabbits (postweaning) weighing 1.5-2.2 kg were used. Both hips were exposed through an anterolateral approach. On the right hip, a fixed area of superolateral physeal cartilage was damaged with drills. Sham open reduction was performed for the left hip. Radiographic changes of the right hips were evident at 6 weeks. At 12 weeks, the right hip dislocated in a posterior and superior direction. The left hip remained normal. Histopathologic analysis correlated strongly with the radiographic findings. There were thinning of cartilage cells of the acetabulum, with disorganization. The acetabular roof was poorly formed. The lateral acetabular epiphysis is vital to the development of the acetabular roof. Damage to this epiphysis may result in acetabular maldevelopment and subsequent hip instability. We tested the hypothesis that abnormality in this epiphysis can give rise to abnormal acetabular development.

Acetabulum↗