High tibial osteotomy (HTO) is a common treatment for medial compartment arthritis of the knee in younger, more active patients. The HTO shifts load away from the degenerative medial compartment and into the lateral compartment. This change can be accomplished with either a lateral closing or a medial opening wedge HTO. An HTO also potentially affects leg length. Mathematical models predict that the osteotomy type (opening versus closing) and the magnitude of the correction determine the change in leg length, but no in vivo studies have been published. The purpose of this study is to quantify and compare leg length change following opening and closing wedge HTO. Retrospective cohort study – Level III evidenceIntroduction:
Study Design:
Appropriate positioning of total knee arthroplasty (TKA) components is a key concern of surgeons. Post-operative varus alignment has been associated with poorer clinical outcome scores and increased failure rates. However, obtaining neutral alignment can be challenging in cases with significant pre-operative varus deformity 1) In patients with pre-operative varus deformities, does residual post-operative varus limb alignment lead to increased revision rates or poorer outcome scores compared to correction to neutral alignment? 2) Does placing the tibial component in varus alignment lead to increased revision rates and poorer outcome scores? 3) Does femoral component alignment affect revision rates and outcome scores? 4) Do these findings change in patients with at least 10 degrees of varus alignment pre-operatively?Background:
Questions:
For many patients, UKA is a good alternative to total knee arthroplasty (TKA) or high tibial osteotomy (HTO). Strong evidence that gender influences outcomes following UKA could alter UKA selection criteria. No prior series has been specifically designed and matched to compare outcomes based on gender. The purpose of this study was to elucidate the effect of gender on the clinical outcome of UKA while controlling for other variables that may affect outcome. Between 1988 and 2006, 257 UKA's were carried out in our department. We studied two groups of 40 patients of each gender, matched by pre-operative clinical and radiological presentation, and with post-operative follow up of at least 2 years. The mean age at operation was 71 years and the mean follow-up was 5.9 years. In both groups, IKS score improved significantly. When comparing the male and female groups post-operatively, no significant differences were found between IKS knee or function scores, limb alignment, or the incidence of radiolucent lines. No difference was found between groups in terms of range of motion or radiologic progression of arthritis. Both tibial (p<0.001) and femoral (p<0.001) component sizes were significantly larger in the male group than the female group. For males, the size of both the femoral (r2=0.12, p=0.033) and tibial (r2=0.29, p=0.0005) components correlated with patient height. For females, the size of neither the femoral (r2=0.000082, p=0.96) nor tibial (r2=0.0065, p=0.63) components correlated with patient height. The key finding in this study is that when patients are selected for UKA according to specific selection criteria (including avoiding performance of UKA in younger patients and patients over 85 kg), gender is not a predictor of outcome based on IKS scores. When using these selection criteria, gender should not be considered when determining whether to perform a UKA.
Microbiological diagnosis of bone and joint infections (BJIs) currently relies on standard cultures which are time consuming and lack sensitivity. Various molecular approaches have been described and allowed improvement of BJI diagnosis. This study evaluated for the first time the performance of a DNA microarray-based assay (Prove-it™ Sepsis assay, PISA) for the rapid (<6 hours) detection and identification of 50 different species involved in BJI directly from clinical samples. We retrospectively selected 130 bone and joint samples (67 synovial fluids and 63 bone biopsies) including 114 positive and 16 negative samples. The microbiological diagnosis had been previously established either by culture(C+, n=53) or by PCR16S and sequencing when culture was negative (C-/PCR+). The positive samples were selected to match the species targeted on the DNA microarray. DNA extraction was performed before proceeding to PISA amplification and hybridization on every selected sample.Introduction
Material and methods
To our knowledge in medial unicompartmental knee arthroplasty (UKA) no study has specifically assessed the difference in outcome between matched gender groups. Previous unmatched gender studies have indicated more favourable results for women. 2 groups of 40 of either sex was determined sufficient power for significant difference. These consecutively were matched with both the pre-operative clinical and radiological findings. Minimum follow up of 2 years, mean follow-up 5.9 years. Mean age at operation was 71 years. In both groups, the mean IKS knee and function scores improved significantly (p< 0.001) post operatively. There were no significant differences were between the 2 groups. In both groups mean preoperative flexion was 130 degrees and remained unchanged at final follow-up. No significant differences in preoperative and postoperative axial alignment and in the number of radiolucent lines, between groups. With component size used there was a significant difference (p < 0.001) between the 2 groups. However the size of the femoral or tibial implant used was significantly related (p< 0.001) to patient height for both sexes. Radiolucent lines were more frequent on the tibial component, but were considered stable with none progressing. No revisions for component failure. 1 patient in each group developed lateral compartment degenerative change. Male group; one conversion to TKA for undiagnosed pain, three patients underwent reoperation without changing the implant. Female group; no implants were revised, and two patients required a reoperation. Kaplan-Meier 5-year survival rate of 93.46% (84.8; 100) for men and100% for women. The survival rate difference is not significant (p=0.28).Method
Results
Rapid identification of bacteria from extemporaneous samples would greatly help management of prosthesis joint infection. The aim of the present retrospective study was to evaluate a new molecular assay (GeneXpert MRSA-SA SSTI (Cepheid)) for detecting Staphylococcus aureus (SA) and methicillin resistance directly from bone and joint samples in less an hour (58 minutes). Retrospective study using 91 frozen samples (76 patients) of joints (n=24), bone biopsies (n=42) and tissue biopsies (n=25): SA positive samples: n=72 (methicillin susceptible SA (MSSA), n=63; methicillin resistant MRSA, n=9) SA positive samples: n=19 The results were compared with routine results (culture in solid and liquid medium, identification and susceptibility test) from each participating lab.Introduction
Material et method
It is documented in the literature the very good results of lateral unicompartmental knee arthroplasty (UKA) when the standard accepted indications are followed. In our experience these indications can be extended to include post-traumatic osteoarthritis (OA) with malunion secondary to tibial plateau fracture. We report our results concerning 15 UKAs in these particular situations. From 1985 to 2009, we performed 15 lateral UKAs in 15 patients for post traumatic OA secondary to malunion following a tibial plateau fracture. 7 were female and 8 male. The mean age of the patients at the time of the index procedure was 45±17 years and the mean delay from initial trauma was 5.4 years. The average follow-up was 108 months (range 12–265 months).Introduction
Material and methods
isolated descent (n=15), isolated medial shift (n=19), and descent and medial shift (n=95). The degree of the medial shift and the descent depended on the distance from the tibial tuberosity to the trochlear notch and the Caton-Deschamps index measured preoperatively. Patients who underwent surgery for chronic anterior laxity and/or meniscal lesions were excluded (n=3). All patients were free of osteoarthritis before surgery. A complete radiographic series was available for 102 knees. Unilateral periodic dislocation of the patella was present in 60 patients whose knee x-rays were obtained bilaterally.
Recently in Europe, Unicompartmental Knee Arthroplasty (UKA) has regained interest in the orthopedic community; however, based on various reports, results concerning UKA for isolated lateral compartment arthritis seemed to be not as good as for medial side. In 1988 our department started using Unicondylar Knee Pros-thesis with a fixed all polyethylene bearing tibial component and resurfacing of the distal femoral condyle. The aim of this study is to report on our personal experience using this type of implant for lateral osteoarthritis with a long follow-up period. Between January 1988 and October 2003, we performed 54 lateral UKAs (52 patients) and all were implanted for lateral osteoarthritis (3 cases of which were posttraumatic). 52 knees in 50 patients were available after a minimum duration of follow-up of five years (96.3 %). The mean age of the patients at the time of the index procedure was 72.2±1.5 years. The mean duration of follow-up was 100.9 months (range 64 – 189 months). At follow up, 4 underwent a second surgery: one conversion to TKA for tibial tray loosening at 2 years and 3 revisions for UKA in the medial compartment. No revision surgery was necessary for wear of either of the two components, nor for infection. The mean IKS knee score was 94.9 points, with mean range of motion 132.6° (range, 115–150) and a mean IKS function score totaling 81.8 points. The average femorotibial alignment was 1.8° (range −6° to 12°). Radiolucent lines in relation to the tibial component were appreciated in 6 knees and to the femoral component in 1 knee. Implant survival was 98.08% at ten years. The UKA with a fixed bearing tibial component and a femoral resurfacing implant is a reliable option for management of isolated lateral knee osteoarthritis. It offers excellent medium-term results for both functional level and implant survival which even currently enable us to widen our selection criteria to include younger patients or those associated with starting patellofemoral osteoarthritis.
clinical outcome, ligamentous stability and alignment after application of the various medial release techniques (capsular release and deep MCL, pie crust of superficial MCL, superficial MCL release on the tibial side, release of semimembranosus tendon) and to propose a rationale for their use.
In 255 of the 359 (71%) primary TKA’s, symmetrical gaps could be achieved by releasing the capsula and the deep MCL (group 0). In 87 cases (24%), an additional piecrust of the superficial MCL was necessary (group 1). In 55 cases out of these 87 an additional release of the insertion of the semimembranosus was performed. In 17 out of the 359 (5%), the medial tightness necessitated a distal release of the superficial MCL (group 2).
The mean preoperative mechanical femorotibial angle (MFTA) was 174.0, 172.1 and 169.5 and was corrected postoperatively to 179.1, 179.2 and 177.6 for group 0, 1 and 2 respectively. At 12 months, mediolateral stability was clinically evaluated as normal in 97% for group 0, 95% for group 1 and 83% for group 2. Three percent (3%), 5% and 17% has a mediolateral laxity ranging from 6–9 degrees for group 0,1 and 2, respectively.
Medial patello-femoral degenerative changes were found more frequently and these lesions were more pronounced: 20% had narrowing <
50% (IKDC C) and 4% had narrowing >
50% (IKDC D). Onset of medial patellofemoral osteoarthritis was correlated with medial femorotibial osteoarthritis (p<
0,001). Patellar height was statistically different between the operated and controlateral knee (CDI = 0.92 and 0.96, p<
0.001). Patella baja (CDI<
0.8, frequency 9.9%) was correlated with medial femoro-patellar osteoarthritis (<
0.001) and postoperative cast immobilisation (p=0.047).
This study presents the results of 1188 original and innovative posteriorly stabilized TKA procedures in which the femoral bone stock is preserved with a shallow compartment insofar as possible. The TKA procedure is directly derived from Insall’s original technique, except for the posterior stabilisation design, where a third median condyle starts working at 30° of knee flexion. A total of 1188 primary TKA procedures were consecutively performed in a university hospital. Average follow-up was 30 months (0–168 months). The implants were cemented (except for 35 femoral components) and the patella resurfaced (except for nine cases). Clinical results were assessed using the IKS Score. The quality of the implantation was analysed on long-leg X-rays (1175 preoperative and 883 postoperative long-leg films available at follow-up). The results showed that 95% of patients were very satisfied or at least satisfied. Knee score and functional scores were 44 and 54 preoperatively and 90 and 78 postoperatively. Mean range of motion was 116°. On X-ray analysis, the average mechanical femorotibial angle was 179° postoperatively. Survival of the implant for revision was 94.2% at 14 years. We performed 83 re-operations (nine patellar fractures, 14 infections, 12 cases of stiffness and 11 clunck syndromes), including 33 component revisions. Clinical results compared favourably with the literature. This original posterior stabilisation design confirmed the good and excellent results at follow-up. We obtain good range of motion, and no revision was due to polyethylene wear.