Computer navigation assisted fixation in neglected C2-C3 dislocation in an adult

A 49-year-old male presented with neck pain and deformity following an industrial accident sustained two months back. His neurology was normal except for a minimal weakness in left biceps (grade 4/5). Radiographs, magnetic resonance imaging and computed tomographic scan revealed fracture dislocation of C2-C3 with significant lateral translation of C2 over C3 without disc herniation. In view of unsuccessful closed reduction and absent disc herniation at the level of dislocation, a posterior only reduction, stabilisation and fusion with Iso-C 3D computer navigation-assisted cervical pedicle screw fixation with transverse rod-screw construct was performed. At 6 months followup the patient was completely relieved of his symptoms and was able to return to his previous occupation. The rare case is reported for the management by Iso-C 3D computer navigation assisted cervical pedicle screw fixation and reduction with transverse rod-screw construct at each involved level.     

Direct repair of lumbar spondylolysis by Buck��s technique

Background:

The lesion in spondylolysis is a nonunion that follows a fatigue fracture of pars interarticularis. Direct repair of the pars defect is a logical alternative to fusion as it helps to preserve the motion segment and prevents abnormal stresses at the adjacent levels. The purpose of the study is to analyze the clinical and radiological results of direct screw osteosynthesis of the pars defect by the Buck’s method in patients with symptomatic spondylolysis with or without grade 1 spondylolisthesis.

Materials and Methods:

Nine patients (six males, three females, mean age 24 years) with symptomatic spondylolysis with or without grade 1 spondylolisthesis and a normal disc in magnetic resonance imaging (MRI), who failed conservative treatment, underwent surgery between January 2000 and April 2009. Of them five patients had bilateral lysis at one level, one had bilateral lysis at three levels and two levels each and two had unilateral lysis at one level. Direct pars repair by the Buck’s method with internal fixation of the defect using 4.5 mm cortical screws and cancellous bone grafting was done. The mean follow-up period was 45 months. MacNab criteria were used to evaluate the postoperative functional outcome. Healing of the pars defect was assessed by plain radiographs and computed tomography (CT) scan.

Results:

Spondylolysis was bilateral in seven and unilateral in two patients. Two patients had associated grade 1 spondylolisthesis. The mean operative time was 58 minutes (range 45 – 75 minutes) and blood loss was 98 ml (50 – 140 ml). Although radiological fusion was observed in all patients at a mean follow-up of 45 months (range 9 to 108 months), the functional outcome was excellent in two patients and good in five, with one fair and one poor result. The overall result of the procedure was satisfactory in 78% (7/9) of the patients. The two patients with associated grade 1 spondylolisthesis had fair and poor results. No complications were encountered in the perioperative or postoperative period.

Conclusions:

In carefully selected patients, direct repair of the pars defect by the Buck’s technique of internal fixation and bone grafting was a safe and effective alternative to fusion in younger patients with symptomatic spondylolysis, without associated spondylolisthesis, who failed conservative management.     

Top advances of the year: Precision oncology

The advent of precision medicine has changed the landscape of oncologic biomarkers, drug discovery, drug development, and, more importantly, outcomes for patients with cancer. Precision oncology entails the genomic profiling of tumors to detect actionable aberrations. The advances in clinical next-generation sequencing from both tumor tissue and liquid biopsy and availability of targeted therapies has rapidly entered mainstream clinical practice. In this review, recent major developments in precision oncology that have affected outcomes for patients with cancer are discussed. Rapid clinical development was seen of targeted agents across various mutational profiles such as KRASG12C (which was considered “undruggable” for almost 4 decades), Exon 20 insertions, and RET mutations. Approaches to precision chemotherapy delivery by the introduction of antibody drug conjugates in the armamentarium against lung cancer has been appreciated.     

Phase 1 trial of ADI-PEG20 plus cisplatin in patients with pretreated metastatic melanoma or other advanced solid malignancies

Background Arginine depletion interferes with pyrimidine metabolism and DNA damage-repair pathways, and pairing arginine deiminase pegylated with 20,000-molecular-weight polyethylene glycol (ADI-PEG20) with platinum enhances cytotoxicity in vitro and in vivo in arginine auxotrophs.Methods This single-centre, Phase 1 trial was conducted using a 3 + 3 dose escalation designed to assess safety, tolerability and determine the recommended Phase 2 dose (RP2D) of ADI-PEG20.Results We enrolled 99 patients with metastatic argininosuccinate synthetase 1 (ASS1) deficient malignancies. We observed no dose-limiting toxic effects or treatment-related mortality. Three percent of patients discontinued treatment because of toxicity. After treatment, 5% (5/99) of patients had partial responses, and 41% had stable disease. The median progression-free and overall survival durations were 3.62 and 8.06 months, respectively. Substantial arginine depletion and citrulline escalation persisted in most patients through weeks 24 and 8, respectively. Tumour responses were associated with anti-ADI-PEG20 antibody levels at weeks 8 and 16 (p = 0.031 and p = 0.0357, respectively).Conclusion Concurrently administered ADI-PEG20 and cisplatin had an acceptable safety profile and had shown antitumour activity against metastatic ASS1-deficient solid tumours. Further evaluation of this treatment combination is warranted.Subject terms: Cancer, Cancer therapy     

High Prevalence of Human Papillomavirus Types 56 and 70 Identified in the Native Populations of Sabah,Malaysia

Background: Cervical cancer is currently the third most common female cancer in Malaysia , with the humanpapillomavirus (HPV) considered as one of the important contributory factors. This study was conducted to determineHPV prevalence, its genotype distribution, and other potential risk factors among women in Kota Kinabalu, Sabahin order to evaluate the likely efficacy of current HPV vaccines in the local population. Methods: A total of 240cervical samples were collected and subjected to DNA extraction, PCR amplification using the MY09/MY11 primerpair, and restriction fragment length polymorphism (RFLP) for HPV detection and genotyping. Sociodemographic,clinical, and behavioural data were also collected via questionnaires. Results: The prevalence of HPV infection was9.6%. The most common HPVs among 13 genotypes were high-risk HPV-56 (16.7%) and probable high-risk HPV-70(16.7%) followed by HPV-16, -58, -53, -61, -33, -59, and -66 (in decreasing order of prevalence) including the raregenotypes: HPV-62, -81, -82 and -84. Statistical analyses using logistic regression models showed that HPV infectionwas significantly associated with employment (OR 4.94; CI 1.58-15.40) and education at secondary/high school level(OR 0.13; CI 0.03-0.62). Conclusion: Distribution of HPV genotypes in Sabah indicated a high prevalence of HPV-56and -70 which are among the rare HPV types in West Malaysia and merit consideration in future strategies for HPVvaccination specifically for local Sabahan women.     

Resident Cardiac Mast Cells: Are They the Major Culprit in the Pathogenesis of Cardiac Hypertrophy?

Mast cells originate from pluripotent progenitor cells in bone marrow and are major players in the inflammation process. The involvements of mast cells in various cardiovascular complications such as arrhythmias, ischaemia reperfusion injury and graft rejection are well documented. Moreover, recent studies suggest the involvement of mast cells in cardiac hypertrophy and heart failure. The present review focuses on the role of mast cells in the development of cardiac hypertrophy and heart failure.     

The effect of prolonged exercise on lipid peroxidation in eumenorrheic female runners.

PURPOSE: Recently a protective role has been demonstrated for estrogens as free radical scavengers. In this study, lipid peroxidation was evaluated in eumenorrheic runners before and after participation in a half-marathon. METHODS: Seven female runners who participated in regular training (average 25 miles x wk(-1) and reported regular menses (12/yr) served as subjects. Subjects were all in a low estrogen phase of their menstrual cycle as confirmed by menstrual record and plasma estradiol level (42.71 +/- 21.65 pg x mL(-1). Low density lipoprotein oxidation (formation of conjugated dienes) was determined 2 h prerace and 5 min after subject's completion of the race. RESULTS: Results showed a significant increase in lag phase time of conjugated dienes after prolonged exercise (28.43 +/- 4.89 min vs postrace 35.21 +/- 4.32 min, P < 0.05). No correlation between mean levels of estradiol and mean lipid peroxidation levels at rest, 5 min after exercise, or difference (prepost) was observed. CONCLUSION: Prolonged endurance exercise does not appear to increase potential for lipid peroxidation in trained eumenorrheic runners during a low estrogen phase of the menstrual cycle.