IV.

This case supports previous reports of cobalt toxicity secondary to catastrophic third-body wear of a CoCr femoral head following a fractured ceramic bearing. It also demonstrates the potential reversibility of many systemic sequelae associated with cobalt toxicity. To our knowledge, this case represents the highest documented blood cobalt level (45,840 nmol/L).

Introduction: Articular cartilage has a poor capacity for regeneration if damaged. Various methods have been used to restore the articular surface, improve pain, function, and slow progression to osteoarthritis. Method: A PubMed review was performed on 18 March, 2010. Search terms included "autologous chondrocyte implantation (ACI)" and "microfracture" or "mosaicplasty". The aim of this review was to determine if 1-stage or 2-stage procedures for cartilage repair produced different functional outcomes. Results: The main procedures currently used are ACI and microfracture. Both first-generation ACI and microfracture result in clinical and functional improvement with no significant differences. A significant increase in functional outcome has been observed in second-generation procedures such as Hyalograft C, matrix-induced ACI, and ChondroCelect compared with microfracture. ACI results in a higher percentage of patients with clinical improvement than mosaicplasty; however, these results may take longer to achieve. Conclusion: Clinical and functional improvements have been demonstrated with ACI, microfracture, mosaicplasty, and synthetic cartilage constructs. Heterogeneous products and lack of good-quality randomized-control trials make product comparison difficult. Future developments involve scaffolds, gene therapy, growth factors, and stem cells to create a single-stage procedure that results in hyaline articular cartilage.

a b s t r a c tAims: To highlight a case of recurrent atraumatic anterior hip dislocation management using a dual mobility prothesis. Methods: The stability of the patient's hip was assessed using X-ray and MRI scans. Upon the third spontaneous anterior dislocation it was decided with the patient's consent to undergo a total hip replacement. A piriformis sparing anterior approach was use with the insertion of a dual mobility bearing. This consisted of an uncemented porous titanium cup articulating with a 28 mm head in a 42 mm mobile polyethylene liner. Results: Mobilising pain free at 6 weeks post operation with no further dislocations at 6 months follow up. Conclusion: Dual mobility hip replacements was used successfully in our patient with recurrent atraumatic anterior hip dislocation.

Purpose The study sought to investigate the effectiveness of a cryocompression Game Ready™ (GR) versus usual care protocol (UC) on early post-operative recovery following total knee arthroplasty. Methods This study prospectively randomised 72 total knee arthroplasties to a 2-week (from day 0) intervention of GR treatment (n = 36, 63.9% females) or UC of ice with static compression (n = 36, 45.7% females). Knee flexion and extension range of motion (ROM), a visual analogue pain scale and limb circumference were documented at day 1, 2 and 14, as well as 6 weeks post-surgery. Medication usage and length of hospital stay were documented. Patient-reported outcome measures (PROMs) included the Knee Injury and Osteoarthritis Outcome Score and a Patient Satisfaction Questionnaire. Statistical analysis using linear mixed modelling and analysis of variance table with Satterthwaite's method were used along with two-tailed t-tests. Results There were no significant group-by-time interactions regarding any of the outcomes. The GR group had 19% lost to follow-up at 2 weeks, while the UC group had 8%. The GR group demonstrated significantly better knee extension ROM at day 1 (p = 0.048) and day 14 (p = 0.007) compared with the UC group. There were no group differences (n.s.) observed in pain, flexion ROM, limb circumference, opioid use or PROMs. Overall, higher pain levels resulted in increased opioid intake (p = 0.002), older patients used significantly less opioids (p < 0.001) and males reported significantly less pain than females (p = 0.048). No adverse effects were observed due to either protocol. Conclusion Despite patients gaining significantly more knee extension during the initial two-week intervention period when using GR compared to UC, this effect was likely due to chance. No further significant differences were observed between the groups during or after cession of the intervention. Level of evidence Level 2.