Biomedical subjects

J A Goldberg

Publications and source records attributed to J A Goldberg.

At least 19 recordsLinked to original sources

PubMed2003

Surgical management of large rotator cuff tears combined with instability in elite rugby football players.

Large rotator cuff tears are extremely uncommon in young people and when they occur they may be associated with shoulder instability. This paper reports on a series of six elite rugby union and rugby league footballers who presented with shoulder instability and large rotator cuff tears. They were treated with a two stage procedure: an open rotator cuff repair followed by an open shoulder stabilisation some 10 weeks later. All had successful outcomes. The paper also highlights the risk of tearing the rotator cuff when a patient continues to play contact sport with an untreated unstable shoulder.

Adult↗

PubMed2002

Total hip arthroplasty for arthrodesed hips.

The benefits of converting an ankylosed or arthrodesed hip to total hip arthroplasty have been reported in the literature as have the technical difficulties associated with this procedure. This review, however, outlines the experience of a single surgeon (WJMB) at a single institution using uncemented prostheses. Between November 1991 and June 1996, 5 arthrodesed hips underwent uncemented total hip arthroplasty in 4 males and 1 female. Clinical and radiological follow-up review was for at least three years in all patients. In general, patients were satisfied with the outcome of their surgery with Harris Hip scores improving from an average of 62 preoperatively to an average of 72 postoperatively. The surgical outcome in these difficult cases was not as satisfactory as for routine total hip arthroplasty. Meticulous preoperative planning is required to aim toward leg length restoration and restoration of the abductor moment arm. A modular prosthesis allows versatility at surgery.

Adult↗

PubMed2002

Salvaging unstable or recurrent dislocating total hip arthroplasty with the constrained acetabular component.

PURPOSE: To review cases of implantation of constraining acetabular components for unstable or recurrent dislocating total hip arthroplasty at the Department of Orthopaedics, Concord Hospital, Sydney. METHODS: A retrospective analysis was performed on prospectively collected data of 13 consecutively enrolled patients. RESULTS: From 1989 to 2000, 13 constraining acetabular components were implanted into 13 patients as a revision procedure. The surgical approach for the implantation of the constrained liner was posterolateral in 11 cases; a modified Hardinge approach was applied in 2 cases. The mean clinical follow-up duration was 43 months (range, 14-121 months) and the mean age at the time of surgery was 73 years (range, 52-84 years). No patients were lost to follow-up. Indications for using the constrained acetabular component were recurrent dislocation in revision hip replacements (n=8), and intra-operative instability (n=5). There were no episodes of dislocation of the constrained arthroplasty. In 7 cases, the constrained component was implanted into a previously well-fixed shell. CONCLUSION: We recommend the judicious use of the constrained component in cases of hip instability during or after total hip arthroplasty when other methods are not successful.

Acetabulum↗

PubMed2001

Synchrony of rest tremor in multiple limbs in parkinson's disease: evidence for multiple oscillators.

Recent evidence points to involvement of central nervous system oscillators in Parkinson's disease (PD) rest tremor. It remains unknown whether one or multiple oscillators cause tremor in multiple limbs. Based on the prediction that multiple oscillators would cause low coherence even with similar average frequency, we studied 22 PD patients using accelerometers on multiple limbs. Records were digitized and spectral analysis was performed. Peak frequencies in the arms, legs, and chin were similar, indicating that biomechanical factors did not determine the frequency. Coherence between different axes of individual accelerometers and between different segments of the same limb was high. However, coherence between tremor in different limbs was low. There was no consistent pattern across patients of ipsi- vs. contralateral predominance of coherence. These data suggest that tremor in PD is generated by multiple oscillatory circuits, which operate on similar frequencies.

Aged↗

PubMed2000

Potential role of doppler perfusion index in selection of patients with colorectal cancer for adjuvant chemotherapy.

BACKGROUND: As yet there is no established method of accurately identifying patients with colorectal cancer who, despite undergoing apparently curative resection, are at high risk of recurrence. We assessed whether the doppler perfusion index (DPI; ratio of hepatic arterial to total liver blood flow) could be used to select patients who should receive adjuvant chemotherapy. METHODS: We studied 120 patients undergoing curative surgery for colorectal cancer. DPI was measured before surgery with colour duplex doppler ultrasonography. A DPI value of at least 0.3 was defined as abnormal. All patients were followed up until death or for at least 5 years. RESULTS: At 5 years, patients with Dukes' stage A or B tumours (n=61) had recurrence-free survival of 57% and overall survival of 64%, compared with 39% and 42% for patients with Dukes' stage C tumours (n=59; p=0.016 and p=0.008, respectively). 47 patients had normal DPI values and 73 patients had abnormal values. Patients with normal DPI had recurrence-free survival of 89% and overall survival of 91%, compared with 22% and 29% for those with abnormal DPI values (both p<0.0001). CONCLUSIONS: DPI can be used to identify patients with colorectal cancer at high risk of recurrence who are in need of adjuvant treatment. However, further studies with larger numbers of patients are needed to confirm these findings.

Adult↗

PubMed2000

A new technique of subtrochanteric shortening in total hip arthroplasty: surgical technique and results of 9 cases.

Total hip arthroplasty for severe chronic proximal femoral migration, most commonly seen in congenital dislocation of the hip, has been associated with high rates of complications. A new technique of femoral subtrochanteric shortening osteotomy with the prosthesis in situ is described. This technique minimizes the potential complications, allows for correction of severe femoral neck anteversion, and gives excellent rotational stability, while preserving the proximal femur for better press-fit cementless fixation. In this series, there were 9 cases: 6 women and 2 men with a mean age of 53 years (range, 26-77 years). The average follow-up period was 56 months (range, 6-86 months). The mean preoperative Harris Hip Score was 31 (range, 20-35), and the mean postoperative score was 81 (range, 60-98). At follow-up, all patients reported significant pain relief and functional improvement. All osteotomies appeared to be healed on radiographs by 12 weeks. There were 3 complications. The first complication was a recurrent dislocation resulting from muscle incompetence, which was revised using a constrained liner and a 32-mm head with no further dislocations. The second complication was a breach of the femoral shaft, which was treated operatively using a longer stem. The third complication was a proximal femoral shaft split, which was treated by leaving the cerclage wire in situ. This technique should be considered in cases of congenital dislocation of the hip and when femoral shortening is needed.

Adult↗

PubMed2000

Exposure in difficult total knee arthroplasty using coronal tibial tubercle osteotomy.

Exposure in a total knee arthroplasty can be challenging regardless of whether it is a difficult primary or a revision. Various techniques both proximal and distal to the patella have been described and implemented to gain exposure and improve knee flexion. When patella eversion is not possible due to previous surgery or severe preoperative knee flexion contracture, a coronal tibial tubercle osteotomy may be utilized. We present successful results utilizing the coronal tibial tubercle osteotomy procedure. The technique involved in this series is based on that described by Whiteside. It involves the development of a long lateral musculoperiosteal flap incorporating the tibial tubercle and anterior tibia, and leaving the proximal tibial cortex intact. This is extended along the tibia distally for 10 cm. It finishes by gradually osteotomising the anterior surface of the tibial crest. The tubercle is reattached with wires at the end of the procedure. This technique minimizes complications that have been associated with the tibial tubercle osteotomy. The 10 knees in 9 patients, who had total knee arthroplasty with a coronal tibial tubercle osteotomy, were reviewed pre and postoperatively. All knees were assessed using the Hospital for Special Surgery knee score (HSS). The scores averaged 43.6 preoperatively (range, 29 57) and 79.2 postoperatively (range, 67 90), and the mean range of motion was 59.5 degrees preoperatively and 78.0 degrees postoperatively. There were no cases of extension lag. Fixed flexion deformity was present in 3 cases postoperatively. Average time to union at the proximal and distal ends of the osteotomy was 8 and 24 weeks respectively. There was no evidence of nonunion and no other significant complications occurred.

Journal Article↗

PubMed2000

Reinforcement-driven dimensionality reduction--a model for information processing in the basal ganglia.

Although anatomical studies of the basal ganglia show the existence of extensive convergence and lateral inhibitory connections, physiological studies failed to show correlated neural activity or lateral interaction in these nuclei. These seemingly contradictory results could be explained with a model in which the basal ganglia reduce the dimensionality of cortical information using optimal extraction methods. Simulations of this model predict a transient change in the efficacy of the feed-forward and lateral synapses following changes in reinforcement signal, causing an increase in correlated firing rates. This process ultimately restores the steady-state situation with diminished efficacy of lateral inhibition and no correlation of firing. Our experimental results confirm the model's predictions: rate correlations show a drastic decrease between the input stage (cortex) and output stage (pallidum). Moreover, preliminary analysis revealed that pallidal correlations show a transient increase following discrepancies between the animal's predictions and reality. We therefore propose that by using a reinforcement-driven dimensionality reduction process the basal ganglia achieve efficient extraction of cortical salient information that may then be used by the frontal cortex for execution and planning of forthcoming actions.

Animals↗

PubMed2000

A novel approach for assessing the quality and effectiveness of IACUC oversight in investigator compliance.

In research facilities that are registered with the U.S. Department of Agriculture (USDA), funded by the Public Health Service, or accredited by the Association for the Assessment and Accreditation of Laboratory Animal Care (AAALAC) International, the Institutional Animal Care and Use Committee (IACUC) is charged with oversight and evaluation of animal care and use under the terms of the Animal Welfare Act and the Guide for the Care and Use of Laboratory Animals. Although the committee's oversight of investigator compliance may be evaluated annually during USDA inspections and triennially during AAALAC International site visits, routinely assessing the quality and effectiveness of the IACUC's performance is difficult. To measure the successfulness of IACUC oversight, our committee retained a management consultant to objectively design and conduct a confidential survey that could be used to determine how the IACUC could improve the process of facilitating researcher compliance with federal regulations and accreditation standards. The consultant based the content of the survey on confidential interviews with all IACUC members, the IACUC administrator, and a cross sectional representation of the key animal-user population at the facility. The survey was then distributed to the entire animal-user population. Vice-presidents, directors, principal investigators, and technicians were included in the distribution. With a response rate of 34%, the survey results indicated that the facilitation process warranted refinements. The consultant provided the IACUC with its recommendations, which were based on the discernible trending information indicated in the survey responses. The IACUC developed a specific plan of action to address the consultant's recommendations and intends to re-survey the animal-user population once the action plan has been fully implemented. In summary, the survey is an excellent way to assess the quality and effectiveness of IACUC oversight in investigator compliance by determining the level of researcher satisfaction. The evaluation, review, and follow-up process using a confidential interview and questionnaire technique can enhance the performance and effectiveness of IACUC oversight.

Accreditation↗

PubMed1999

Flexor tendon lengthening in zone II injuries.

Primary repair of acute severed flexor tendons in zone II has replaced the "no-man's-land" concept, which advocates secondary procedures. Primary repair can be difficult when there are severe soft-tissue and bony injuries, and may lead to unfavorable results. The authors describe a technique that is simple, quick, and safe, and eliminates the need for tendon harvesting or other secondary procedures. It can also be used when a flexor profundus tendon gap occurs due to the injury.

Adult↗

PubMed1995

Restoration of sensation in paraplegia by a sensory innervated plantar fillet free flap. Case report.

Sensory denervation most likely is the key factor to the multiple physiological derangements that predispose paraplegic patients to recurrent decubitus ulceration. A sensory innervated plantar free flap offers the ability to provide soft tissue coverage and to regain sensory innervation of the ulcer prone area in patients with recurrent ulceration. We present a patient in which an innervated plantar free flap was used to restore sensation to the sacral area in a patient with recurrent ulceration.

Humans↗

PubMed1994

Sensory reinnervation of muscle free flaps for foot reconstruction.

A retrospective study was performed to measure sensibility in sensory-to-motor innervated microvascular muscle transplants to the foot. Seven transplants were on the weight-bearing surface of the foot. Five of seven flaps had light-touch sensation. Mean vibrometer readings of the innervated transplants were 15.7 (range: 5 to 40) vs. 5.3 (range 2 to 9) on the contralateral foot. Semmes-Weinstein scores of the innervated flaps were 3.84 (one), 4.74 (one), 5.46 (two), and 6.45 (three) vs. 3.22 (one), 3.84 (one), 4.08 (one), and 4.17 (four) on the contralateral foot. This study documents that sensory-to-motor innervated free muscle flaps may regain measurable sensibility.

Adult↗

PubMed1993

Early detection of occult colorectal hepatic metastases using duplex colour Doppler sonography.

Previous studies have shown that overt intrahepatic tumours are associated with subtle changes in liver perfusion that can be measured directly using duplex colour Doppler sonography (DCDS). This study assessed the predictive value of DCDS in the early detection of occult colorectal hepatic metastases. Hepatic arterial and portal venous blood flow was measured in 50 control subjects and 135 patients with colorectal cancer, 67 with overt liver metastases and 68 with an apparently disease-free liver on the basis of computed tomography and laparotomy findings. The Doppler perfusion index (DPI), defined as the ratio of hepatic arterial to total liver blood flow, was calculated. Clear separation of the DPI values of controls and those of patients with overt metastases was observed (P < 0.0001). Thirty-eight of the 68 patients with a disease-free liver also had an abnormally high DPI value. After 1 year of follow-up, 21 patients with an abnormally high DPI at the time of apparently curative primary resection had developed liver metastases and a further four had died without post-mortem examination. The 30 patients with normal DPI remain disease-free. The data suggest that DPI is of value in the early detection of occult liver metastases.

Adult↗

PubMed1993

Image-directed Doppler ultrasonography: a novel technique for the diagnosis of colorectal liver metastases.

Image-directed Doppler ultrasonography has been used to measure changes in hepatic arterial and portal venous blood flows in 22 controls and 88 patients with colorectal cancer. Doppler Perfusion Index, (DPI, ratio of hepatic arterial to total liver blood flow) and Doppler Flow Ratio (DFR, ratio of hepatic arterial to portal venous blood flow) of controls and patients with overt liver metastases were clearly separated (p < 0.0001). There was a significant reduction in the Hepatic Arterial Resistive Index (HARI) of patients with overt liver metastases (p < 0.0001). Percentage Hepatic Replacement (PHR) by metastases, measured using a computed tomography scanner, did not correlate with DFR or DPI. The results suggest that the measurement of hepatic perfusion changes using image-directed Doppler ultrasonography may be of value in the detection of small liver metastases.

Adult↗

PubMed1993

Laparoscopic cholecystectomy. Postoperative sonographic findings.

Seventeen consecutive patients undergoing elective laparoscopic cholecystectomy (LC) were serially evaluated with transabdominal ultrasound before, one day after, and six days after LC to document what, if any, changes occur in the surgical bed and surrounding parenchyma. The most common postoperative finding was focal sonolucency in the hepatic parenchyma adjacent to the gallbladder fossa in six (35%) of 17 patients. Five patients (29%) had postoperative fluid collections in the gallbladder fossa; in four of these five, it was technically difficult to dissect the gallbladder from the liver at the time of original surgery. In one patient the fluid resolved by the sixth postoperative day. It persisted in the remaining four. Two patients had transient ductal dilation and one had pneumobilia. Shadowing and ring-down artifact was identified in 12 patients due to surgical clips in the triangle of Calot. Because gallbladder fossa fluid may persist up to six days after uncomplicated laparoscopic cholecystectomy, caution should be used before attaching significance to isolated imaging findings. Clinical judgement remains the best means of selecting which patients need additional evaluation.

Abdomen↗

PubMed1993

Hepatic arterial haemodynamics changes following intra-arterial angiotensin II infusion: duplex/colour Doppler sonography.

Previous studies have shown that the delivery of cytotoxic microspheres to liver tumours may be improved by manipulating the tumour to normal liver blood flow ratio using angiotensin II (AT-II). The optimization of this targeting requires the assessment of the temporal blood flow changes induced by agents such as AT-II. Duplex/colour Doppler sonography (DCDS) was evaluated as a means of studying the effects of AT-II infusion on hepatic arterial blood flow (HABF) and arterial resistance in patients with colorectal liver metastases. HABF was measured continuously in six patients with colorectal liver metastases using DCDS before, during and after an infusion of AT-II (15 micrograms in 3 ml of saline over 90 s) via a hepatic artery catheter. The baseline level of HABF was 320 +/- 87 ml/min (mean +/- S.D.), and this was reduced by 70-76% within 30 s of the start of AT-II infusion. HABF recovered rapidly from the end of the infusion, and increased by up to 20% above the baseline for approximately 2 min. Arterial resistance showed reciprocal changes in all cases. These changes were both quantitatively and qualitatively similar to intra-operative measurements previously performed in the same patients using a standard intra-operative flowmeter. The degree of concordance obtained from the intra- and post-operative measurements confirms the effectiveness of DCDS in assessing the temporal changes in hepatic arterial blood flow caused by AT-II. Prior to the start of therapy, the evaluation of vasoconstrictor agents should be carried out in individual patients to predict response, in order to establish the optimal phase for the injection of cytotoxic microspheres.

Aged↗

PubMed1993

Duplex/colour Doppler sonography: measurement of changes in hepatic arterial haemodynamics following intra-arterial angiotensin II infusion.

Angiotensin II (AT-II) has been used to target regionally-administered cytotoxic microspheres in patients with intrahepatic tumours. The optimisation of vasoconstrictor targeting requires a knowledge of the blood flow changes induced by agents such as AT-II. We therefore assessed duplex/colour Doppler sonography (DCDS) as a means of evaluating the effects of AT-II infusion on hepatic arterial blood flow (HABF) and arterial resistance in patients with intrahepatic tumours. HABF was measured continuously in nine patients using DCDS before, during and after an infusion of AT-II (15 micrograms in 3 ml of saline over 90 s) via a hepatic artery catheter. In seven patients with less than 30% hepatic replacement by tumour, the baseline level of HABF was 331 +/- 85 ml min-1 (mean +/- s.d.), and this was reduced by 75-80% within 30 s of the start of AT-II infusion. HABF recovered rapidly from the end of the infusion, and increased by up to 20% above the baseline for approximately 2 min. In two patients with greater than 50% hepatic replacement, HABF showed no reduction but rose continuously from the start of AT-II infusion, increasing by a factor of 2-2.5 after 3-4 min. Arterial resistance showed reciprocal changes in all cases. We conclude that DCDS is effective in assessing the temporal changes in hepatic arterial blood flow caused by AT-II. In order to optimise tumour targeting, the injection of microspheres loaded with cytotoxic drugs should be completed before the end of the AT-II infusion. The targeting advantage of AT-II in patients with a high percentage hepatic replacement by tumour should be re-assessed.

Aged↗

PubMed1993

Closure of myelomeningocele using skin from stillborn twin.

We report a case of homologous skin transplantation from a stillborn twin to the surviving twin for coverage of a myelomeningocele defect. Genetic studies were not available preoperatively, however, similar morphogenetic anomalies of the twins suggested monozygosity. Long-term follow-up revealed a well-healed graft. Cutaneous genetics and literature review of twin homologous skin transplantation are presented.

Diseases in Twins↗