Does the use of tibial stem extensions reduce the risk of aseptic loosening in obese patients undergoing primary total knee arthroplasty: A systematic review and meta-analysis.

BACKGROUND: This study aimed to compare the risk of revision for aseptic loosening in obese (body mass index >30 kg/m2) patients with stemmed (ST) versus non-stemmed (NST) tibial implants in primary total knee arthroplasty (TKA). METHODS: A systematic review and meta-analysis were conducted following PRISMA and MOOSE guidelines. Studies reporting a direct comparison between ST and NST tibial implants in obese patients were included. The primary outcome of interest was revision for aseptic loosening. Outcomes were analysed using meta-analysis of relative risk. Risk of bias assessment was performed using the Newcastle-Ottawa Scale for observational studies and the RoB-2 Cochrane tool for randomised studies. RESULTS: Seven studies met the selection criteria, consisting of four cohort studies and three randomised controlled trials. Mean follow up time for the eligible cohort was 62.6 months. Meta-analysis demonstrated a statistically significant reduction in the risk of aseptic revision in the ST group compared with the NST group (risk ratio 0.25, 95% confidence interval 0.07 to 0.92). After removal of all zero-event studies, the results remained in favour of the ST group (risk ratio 0.15, 95% confidence interval 0.03 to 0.64). CONCLUSIONS: This study found that obese patients undergoing TKA with stemmed tibial implants may have a lower risk of aseptic revision compared with those with non-stemmed tibial implants. However, due to the lack of high-quality literature available, our study is unable to draw a definitive conclusion on this matter. We suggest that this topic should be re-evaluated using higher-quality study methods, particularly national joint registries studies and randomised controlled trials.

Assessment of Shoulder Range of Motion Using a Wireless Inertial Motion Capture Device-A Validation Study.

(1) Background: Measuring joint range of motion has traditionally occurred with a universal goniometer or expensive laboratory based kinematic analysis systems. Technological advances in wearable inertial measurement units (IMU) enables limb motion to be measured with a small portable electronic device. This paper aims to validate an IMU, the 'Biokin', for measuring shoulder range of motion in healthy adults; (2) Methods: Thirty participants completed four shoulder movements (forward flexion, abduction, and internal and external rotation) on each shoulder. Each movement was assessed with a goniometer and the IMU by two testers independently. The extent of agreement between each tester's goniometer and IMU measurements was assessed with intra-class correlation coefficients (ICC) and Bland-Altman 95% limits of agreement (LOA). Secondary analysis compared agreement between tester's goniometer or IMU measurements (inter-rater reliability) using ICC's and LOA; (3) Results: Goniometer and IMU measurements for all movements showed high levels of agreement when taken by the same tester; ICCs > 0.90 and LOAs < ±5 degrees. Inter-rater reliability was lower; ICCs ranged between 0.71 to 0.89 and LOAs were outside a prior defined acceptable LOAs (i.e., > ±5 degrees); (4) Conclusions: The current study provides preliminary evidence of the concurrent validity of the Biokin IMU for assessing shoulder movements, but only when a single tester took measurements. Further testing of the Biokin's psychometric properties is required before it can be confidently used in routine clinical practice and research settings.

Diagnostic accuracy of computed tomography-guided biopsy in pathological fractures.

BACKGROUND: Obtaining a histological diagnosis is essential for appropriate management of pathological fractures. Computed tomography (CT) is an accurate method of obtaining diagnosis for musculoskeletal tumours. We analysed whether diagnostic accuracy was maintained in the evaluation of pathological fractures. METHODS: A retrospective review of 101 consecutive patients presenting to our tertiary musculoskeletal tumour centre with pathological fracture was performed. Patients underwent core needle biopsy under CT guidance of pathological fractures diagnosed by plain radiography and either CT or magnetic resonance imaging. The histopathology of the CT-guided biopsy was compared with the sample obtained from open biopsy or definitive surgery to determine diagnostic accuracy. RESULTS: The mean age at diagnosis was 52 ± 20 years (range: 18-85) in a cohort of 46 men and 55 women. Diagnostic accuracy of CT-guided biopsy was 82.18%. There were 65 malignant and 36 benign tumours with diagnostic accuracy of 86.15% and 80.56%, respectively. The positive predictive value for a malignant tumour was 98.21% whilst it was 93.1% for benign tumours. The femur (53 cases) and humerus (25 cases) were the commonest bones fractured. The most frequent diagnoses were metastasis (20.79%), giant cell tumour (17.82%), osteosarcoma (9.90%) and myeloma (9.90%). There were no complications of CT-guided biopsy. CONCLUSION: Pathological fracture does not confound the diagnosis of musculoskeletal tumours. CT-guided biopsy is an accurate diagnostic tool in the evaluation of pathological fractures. Final diagnosis and management should be made in the context of appropriate anatomical and functional imaging using a multidisciplinary approach.

Analgesic effect of subanesthetic intravenous ketamine in refractory neuropathic pain: a case report.

A 59-year-old male patient with progressive neuropathic pain secondary to chronic idiopathic axonal polyneuropathy responded poorly to conventional therapies including gabapentin, tricyclic antidepressants, serotonin-norepinephrine reuptake inhibitors and opioids. Following continuous intravenous administration of low dose ketamine, an N-methyl-D-aspartic acid receptor antagonist, 20 mg/h for 5 days, almost complete pain relief was obtained without significant side effects. The analgesic effect lasted 10-12 weeks and the ketamine infusion was repeated, with this pattern being maintained for 3.5 years. This supports the growing body of evidence that ketamine may be useful in the management of refractory chronic neuropathic pain. We discuss chronic idiopathic axonal polyneuropathy, neuropathic pain mechanisms, and the use of ketamine in this report.