Novel approaches to prosthetic joint infection

PhD ThesisProsthetic joint infection is a devastating complication affecting around 1% of joint replacements. Patients affected by this frequently require multiple surgeries to try to eradicate the infection in addition to prolonged courses of antibiotics. The diagnosis of infection in itself can be challenging. This work has explored novel approaches to diagnosing joint replacement infection using the Fc receptor CD64 found on neutrophils in peripheral blood as well as new diagnostic markers in synovial fluid using Alpha Defensin. The treatment of joint replacement infection is controversial and this thesis explores the results of patients treated with a less invasive approach known as Debridement Antibiotics and Implant Retention (DAIR). In addition prevention strategies have also been explored with a particular focus on the use of laminar flow operating theatres and an exploration of their effectiveness in the presence of operating theatre lights

Constrained condylar knee systems: A review of five commonly used brands

Purpose Constrained condylar knee (CCK) implants are commonly used in a revision setting. They are designed to fix the prosthesis to the host bone at epiphysis and diaphysis to provide good construct stability and provide flexibility to balance the knee in the coronal and sagittal planes. There are many knee revision systems available which makes it difficult for knee surgeons to choose the ideal implant that is suitable to an individual patient's needs. The study of failed knee revision systems and recent developments in technology and biomaterials has considerably improved our understanding of implant design. Although the CCK systems follow similar principles in design, they are crucially very different and based on contrasting philosophies. Some of these systems are very versatile and user friendly while others are very complex making the procedure and the task of the orthopaedic surgeon difficult. Scope In this review article we consider five of the most commonly used CCK revision systems and provide a detailed discussion of the design features of each system, their potential advantages and limitations and their reported outcomes in the relevant literature. Conclusions There are many differences between the five CCK systems. There are limited outcome data to support the use of any particular CCK system. The newer systems may offer versatility but surgeon's skills and experience may still be the determining factor in the success of revision surgery

Results with nine years mean follow up on one hundred and three KAPS® uni knee arthroplasties: eighty six medial and seventeen lateral

International audiencePURPOSE:The purpose of this study was to present the results of the KAPS® uni knee arthroplasty system, both mobile and fixed bearing with reference to function, alignment and complications in 103 implants with a mean follow-up of nine years.METHODS:This was a retrospective study of 103 unicompartimental knee arthroplasties in 89 patients operated on between March 2005 and March 2010. The population was composed of 50 males and 39 females, with a mean age of 70.5 ± 7.5 years (41 - 90). Eighty-seven patients had a genu varum deformity (84.5%), one of whom had an osteoid osteoma of the lateral tibial plateau and 16 patients had a genu valgum (15.5%). Eighty-six medial prostheses were implanted (82 mobile bearings and 4 fixed bearings) and 17 lateral prostheses (all fixed bearings) including the osteoid osteoma.RESULTS:At a mean follow-up of 107.5 months (73-138), 72 knees (58 patients) were reviewed (70%). The mean IKS score was of 173 ± 31 points (58 - 200). The mean Oxford knee score was 21 ± 8 points (12 - 50). The cumulated survival rate at a follow up of 132 months was 98.2%.CONCLUSION:The KAPS® unicompartmental knee arthroplasty gives efficacious and safe outcomes in the majority of cases at a mean follow-up of nine years. The availability of both fixed and mobile bearings with the same instrumentation, allowing to choose the right implant intra-operatively, is a great advantage in order to avoid the occurrence of some complications, specific to mobile bearing prostheses (dislocation and over-correction)

Influence of the post-operative axis on the clinical results of total knee replacement for severe varus deformities: does a slight residual varus improve the results?

International audiencePURPOSE:Some recent articles have suggested that in the case of large varus deformity, it may be advantageous to leave some residual post-operative varus as a means of improving functional outcome. The objective of this study is to compare the results of total knee replacement (TKR) performed for significant varus deformity (HKA  180°).METHODS:This series was made up of 208 knees. The mean pre-operative HKA angle was 166 ± 3° (154-169°), of which 150 were followed up for a mean 8.5 years (58 lost to follow-up). Based on post-operative radiographs, two groups were formed: group 1 (88 knees) in which post-operative alignment was 177.8 ± 1° (175-179°) and group 2 (62 knees) in which post-operative alignment was 181 ± 1° (180-184°).RESULTS:The mean international knee society (IKS) score for group 1 was 178.8 ± 22 points (113-200) and 181.7 ± 22 points (95-200) for group 2. Oxford knee score was 20.4 ± 9 points (12-45) in group 1 and 19.2 ± 9 (12-50) in group 2. The results were slightly better in group 2 (in slight valgus) but this difference was not statistically significant (p = 0.44 and 0.4).CONCLUSION:The results of knee replacement performed for severe varus deformity are not adversely affected by post-operative valgus alignment. There is in fact a trend towards superior results for neutral or valgus alignment than slight residual varus, but this difference was not statistically significant

Results of the Latarjet coracoid bone block procedure performed by mini invasive approach

International audienceINTRODUCTION:The coracoid block technique described by Latarjet was modified by Patte and Walch in order to increase the glenoid surface. Saragaglia further modified this technique and described a minimally invasive approach which allows faster post-operative recovery. The aim of this study was to evaluate the medium-term functional and radiological results of this technique.METHODS:This is a single surgeon cohort of 40 shoulders in 38 patients (32 men, 6 women) with an average age of 34.5 years operated on between January and December 2014. The skin incision was 3 to 6 cm long allowing the bony block to be passed under the subscapularis tendon without sectioning it and to be placed in lying position. The bone block was fixed with a 6.5 cancellous screw or a 7.0 cannulated screw.RESULTS:At an average follow-up of 48 months, there were no recurrent dislocations. The average WOSI score was 42, the average Constant score was 95 corrected to 97% and the average SSV was 97. Visual analogue scores were 0 at rest and 0.6 with activity. The bone block healed in 92.5% of cases. It was flush with the edge of the glenoid in 84% of cases, lateralised in 10% and medialised in 6% of cases. Mean internal rotation power was 12 kg in the operated shoulder compared with 9 kg in the non-operated shoulder.CONCLUSION:The treatment of recurrent anterior shoulder instability by mini invasive Latarjet gives excellent medium-term functional results. The rate of recurrent dislocation in this series was zero and internal rotation power was well preserved. This is an excellent alternative to arthroscopic procedures which are yet to demonstrate their superiority over open surgery

Ganglion cysts of the proximal tibiofibular articulation: the role of arthrodesis and combined partial fibula excision

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《六朝陶瓷論集》

International audiencePURPOSE:The aim of this study was to evaluate the medium-term results of total knee replacements (TKRs) after medial opening wedge valgising tibial osteotomy to those of primary TKR (TKR1). The hypothesis being that there would be no difference in results between these groups.METHODS:Series 1 was made up of 45 TKRs after medial opening wedge high tibial osteotomy (MHTO)-30 men and ten women at an average age of 69 ± seven years (54-82). This was compared to a second series of TKR1s-30 men and ten women at an average age of 69 ± seven years (55-78). The average IKS scores were 91 ± 22.5 points (42-129) and 86 ± 18 points (38-116) in the two groups respectively. The average pre-operative HKA angle was 179 ± 5° (169-193°) in group 1, and 173 ± 7.5° (161-193°) in group 2. Tibial mechanical axes were 90.5 ± 4° (of which 24 knees had a valgus angle) and 85.05 ± 3.5° (79-93°) in the two groups respectively.RESULTS:All patients were reviewed at an average follow-up of 47 ± 24.5 months for series 1 and 185 ± 8.5 months for series 2. The average IKS score was 184 ± 6 for series 1 (172-200) and 185 ± 8.5 (163-200) for series 2 (p = 0.872). Thirty-seven patients in series 1 and 38 patients in series 2 were either extremely satisfied or satisfied with the intervention. The average post-operative HKA angle was 180.5 ± 2.5° and 181 ± 2° (p = 0.122) and the average tibial mechanical axis was 89 ± 1.5° against 90 ± 1° (p = 0.001). The results of the 24 knees with a valgus tibial mechanical axis were statistically no different.CONCLUSIONS:TKRs post medial opening wedge high tibial osteotomy have identical results to primary TKRs even in knees with a valgus tibial mechanical axis