The aim of this investigation is to firstly quantify the burden of disease, and secondly qualify the organisms being cultured during debridement to establish their sensitivities to available antibiotics. This study will also look at the concomitant burden of Human Immunodeficiency Virus (HIV) and Diabetes Mellitus (DM) in cases of hand sepsis, to establish whether these two disease processes require special consideration and treatment tailoring. The method employed to collect the data will be retrospective collection of patient information, using random sampling. Included patients will be adult patients who undergo debridement and have a sample registered on the National Health Laboratory System (NHLS). The daily intake sheet will be used to collect patients details and these details will then be used to collect results of intra-operative specimens using the NHLS. These patient details will also be used to check patients’ HIV results and HBA1c (Glycated Haemoglobin A1c) results. Majority of the specimens revealed Methicillin Sensitive Staphylococcus Aureus (MSSA), with a reassuringly low rate of Methicillin Resistant Staphylococcus Aureus (MRSA) when compared to international data. The yield of patients tested for HIV or DM was lower than expected, despite this being the standard of care. The projected impact of this study will be assessment of the current burden of disease and then clarification of our current management strategy, in order to assess if it would be possible to change to a more cost-effective antibiotic with a narrower spectrum of bacteria coverage. The potential exists to not only implement cost saving measures, but also promote antibiotic stewardship by decreasing the practice of empiric broad-spectrum antibiotic use.
The most reported benefit of TKA navigation technologies has been the reduction in limb and component alignment outliers. This improvement has not been shown to effect clinical outcomes. This study was designed to compare the functional outcomes between computer assisted techniques and manual techniques. Each group had 60 patients with similar demographics. The average functional outcomes (SF-36, WOMAC, range of motion, pain relief, and knee society score) were the same. The average scores of the SF-36, Knee Society Score, WOMAC were similar for the two groups. However, fewer patients in Group II reported visual analog pain scores greater than 40 at 6 wks, 3 mos and 6 mos. At 1 yr, the pain scores of the two groups were similar. Fewer patients in Group II had KSS scores less than 70 at 3 months, 80 at 6 months, and 90 at one year, than those in Group I. The average range of motion in Group II was greater by 8 degrees at 4 wks and 3 mos, but equal to the average ROM in Group I at 6 and 12 mos. However, the number of patients with less than 90 degrees of motion at each follow-up period was less in Group II than in Group I at each follow-up period. There were fewer superficial wound infections in Group II than in Group I. The average functional outcomes were similar; the results indicate a consistent reduction in outliers in most measured parameters of functional outcomes. In particular, the guidelines for administering pain medication and providing physical therapy were similar for the two groups. The results of this study are parallel to the radiographic results comparing TKA’s performed with manual and computer assisted instrumentation. In those studies, a reduction in outliers was consistently associated with the use of computer assisted techniques.
Customization makes it possible to fulfill design requirements during MIS-THA procedures, and has helped define the parameters of fit and fill. This study describes the results of using customization techniques to develop a femoral implant for utilization. CT-based design criteria for femoral implants has-been developed and used for primary, cement-less, non-minimally invasive THA surgery. Over 1000 procedures performed with these devices have been associated with displaced femoral fractures, and have been revised for septic loosening. This study has 2 parts:
20 implants were designed and implanted with CT-based criteria that utilized the identical fit and fill standards of the custom implants previously established, but had short (<
115 mm), tapered stems; 20 patients underwent primary, cement-less THR wherein an off-the-shelf femoral implant system was determined to fulfill fit and fill requirements of custom implants. The stem of these implants was shortened (95–115 mm) and tapered. Implants in both groups were inserted using a single incision, posterior-lateral MIS approach. Patients were followed clinically and radiographically for six months. Immediate full weightbearing and use of a single cane were encouraged. The use of CT-based customization techniques is helpful for defining design criteria of femoral implants, but the instrumentation for inserting these implants must be adapted to the specific surgery. Customization also facilitates the design and evaluation of CAOS applications for inserting these MIS implants.
The authors strongly recommend that: 1) a surveillance program be established for careful, regular follow-up of patients with THR in place more than 7 years; 2) CT scans be considered as part of that surveillance program, and 3) cups with screws NOT be used routinely in primary THR surgery.
Osteolysis secondary to polyethylene wear is the most serious aseptic long-term complication following THR. Studies have shown that fixation with screws, modularity and lack of extensive bone ingrowth are associated with increased osteolysis. This study examines the initial experience with a cup designed to address these issues. One hundred and twenty-seven consecutive primary THR were performed between 1997–1999 using unce-mented monoblock, elliptical, tantalum cup without screw holes. Average follow-up 40 months (range 24 to 61). 79 THR in females, 48 in males. 48% THR hybrid fixed, 52% uncemented. Average age 61.6 years (range 19 to 88). Pre and post-operative clinical assessment with Harris hip score (hhs), WOMAC, SF-36. One independent, blinded observer performed zonal radiographic analysis with modified DeLee and Charnley method. Average hhs at recent follow-up 93 (range 85 to 100). All shells appear fixed with bone ingrowth. Dome-gaps present in 6 cups post-op; all have filled in. Radiolucencies at follow-up: 4% zone 1, 8% zone 2; none greater than 1 mm. No cup migration. 8 cup related complications: 5 dislocations (4%) 1 subluxation, 2 undisplaced rim fractures (1.7% – no treatment). 3 dislocations, 1 subluxation occurred more than three months post-op. 3 revisions: 1 deep wound infection, 1 liner exchange (using reaming technique), 1 femoral head exchange. Uncemented monoblock, elliptical tantalum cup without holes provides secure, symptom-free fixation at 4 years. No complications associated with use of tantalum. Elliptical shape associated with dome gaps, all of which appeared to fill by 3 months. Monoblock design results in increased polyethylene lip prominence associated with 6 cases of instability. Effect of prominent rim on impingement and long-term wear requires careful follow-up.
Pelvic osteolysis secondary to polyethylene wear is a major complication following THR. Identification of implant specific characteristics associated with osteolysis is essential. The purpose of this study is to compare incidence of CT scan identifiable osteolysis in 2 groups of young, active patients following THR; one with multi-holed acetabular shells with screws, one with cups without screw holes. Between 1990–1993, 77 patients (85 hips) underwent THR with a cementless titanium, multi-holed shell with screws, modular, compression molded polyethylene and an uncemented titanium femoral stem. Average follow-up: 9 years, average age at surgery: 51 years. Between 1984–1987, 163 patients (183 hips) underwent THR with a cementless cobalt-chrome, solid shell, modular, heat-pressed polyeth-ylene liner and uncemented cobalt-chrome femoral stem. Average follow-up: 16 years, average age at operation: 52 years. All polyethylene was irradiated in air. At most recent follow-up, CT scans with metal suppression software was obtained to evaluate incidence of pelvic osteolysis. Patients classified: Group 1-no osteolysis, Group 2-cavitary osteolysis, Group 3-segmental osteolysis. Patients with titanium, multi-holed shells had: Group 1-50.0%, Group 2-38.7%, and Group 3-11.3%. Patients with cobalt-chrome, solid shells had: Group 1-59.3%, Group 2-33.3% and Group 3-7.4%. Although the patients with solid cups had much longer follow-up, less secure capture mechanism, less congruency between polyethylene and shell, and heat-pressed polyethylene, the incidence and extent of pelvic osteolysis was less than in the patients with multi-holed shell with screws. The presence of 6.5 mm cancellous screws is a serious independent risk factor for pelvic osteolysis following THR.