A Prospective Cohort Study of the Therapeutic Patterns, Challenges and Outcomes of Paediatric Femoral Fractures in a Cameroonian Tertiary Center

BACKGROUND

Knowledge of the therapeutic patterns, challenges and outcomes of treatment of paediatric femoral fractures (PFF) helps to better choose the ideal therapeutic modality which is still controversial. However, this data is scarce in the sub-Saharan African literature.

OBJECTIVE

To determine the therapeutic patterns, treatment challenges and outcomes of treatment of PFF in a tertiary care centre in Cameroon.

METHOD

We conducted a prospective cohort study of all consenting consecutive cases of femoral fractures in patients younger than 16 years managed between 2011 and 2015 at the surgical unit of Yaoundé University Teaching Hospital, Cameroon. We analysed demographic data, injury characteristics, fracture patterns, treatment details, therapeutic challenges and outcomes of treatment at 12 months using Flynn's criteria.

RESULTS

We enrolled 30 femoral fractures from 29 children with mean age was 4.2 ± 3.3 years. The male gender, diaphyseal locations and spiral fracture lines were predominant. Main mechanisms of injury were accidental falls, road traffic accidents and game injuries. Fracture management entailed 12 tractions followed by casting, 10 casting alone, four closed reductions followed by casting, two cannulated screw fixations, one pin fixation and one external fixation. The mean duration of consolidation was 10.3 ± 3.9 weeks. The outcome was rated excellent in 28 cases. Limited resources precluded fluoroscopy use, proper anaesthetic management, early rehabilitation and patient-parent satisfaction.

CONCLUSION

Conservative management of PFF yields a good outcome in our setting. However, an improvement in surgical, radiology and anaesthetic infrastructure is needed for optimal PFF care.

The effects of multiple drilling of a bone with the same drill bit: thermal and force analysis

Repeated use of the same drill bit during drilling wears off the cutting edges, which can lead to a significant increase in heat as a result of friction, which is harmful to a bone above 55 °C. Few previous studies have examined the effects of using the same drill bit several times, on temperature. The objective of this study was to determine the effect of each drilling on temperature and force. 72 trials were performed. A total of 24 stainless steel drill bits of ∅3.2 mm were used to drill bovine bone samples. Each drill bit was used at least 3 times. T thermocouples were used to measure temperatures during each drilling test. Possible correlations of cutting parameters were studied. Tests were performed on a test rig measuring forces and temperatures during drilling. Effects of spindle speed (N), feed rate (V_f), and several trials (E) on temperature and forces were measured. Images of the drill bits were analyzed by digital microscopy before and after the drilling series for signs of wear. Temperatures increased significantly from E₁ to E₃. They decreased moderately with V_f. The best cutting conditions were at N = 200 rpm for V_f = 60 mm/min and N = 100 rpm for V_f = 30 mm/min drilling. At N > 200 rpm, they were very high. Temperature rise is significantly related to number of drilling (E), spindle speed (N), and inversely to feed rate (V_f). Analysis of images by digital microscopy confirmed drill bits wearing off, following the number of trials.

Reliability of patient specific instrumentation in total knee arthroplasty

The aim of this study was to compare the precision between Patient Specific Instrumentation (PSI) and Conventional Instrumentation (CI) as determined intra-operatively by a pinless navigation system. Eighty patients were included in this prospective comparative study and they were divided into two homogeneous groups. We defined an original score from 6 to 30 points to evaluate the accuracy of the position of the cutting guides. This score is based on 6 objective criteria. The analysis indicated that PSI was not superior to conventional instrumentation in the overall score (p = 0.949). Moreover, no statistically significant difference was observed for any individual criteria of our score. Level of evidence II.