The in vivo evaluation of patellofemoral contact pressures in a posterior stabilized compared to posterior cruciate sacrificing total knee arthroplasty (TKA). A prospective descriptive non randomized study was performed on 8 patients. A standard approach to a TKA was performed using a balanced gap technique, while the patella was prepared for a resurfacing. The trial components for the posterior stabilized (PS) TKA where inserted including the gas sterilized pressure transducer (a patella button). Soft tissue was approximated and the knee was taken through full range of movement. Patellofemoral pressure was measured and captured continuously through the full range of movement. The posterior cruciate sacrificing (CS) components were inserted into the same patient and the procedure repeated. In addition, anterior translation of the tibia relative to the femur was measured at 90 degrees. The transducer was removed and final components, including a patella resurfacing were inserted.Purpose Of Study
Methods
The literature is unclear about the optimal rotation of the femoral component during TKR. Measured resection techniques rely on the use of bony landmarks, while the balanced gap technique relies on soft tissue tensioning to guide the surgeon in rotating the femoral component. All these techniques still result in a wide range of component rotation. We compared the functional flexion axis (FFA) of 20 replaced knees to that of the contralateral normal knee to determine whether a balanced gap technique allowed us to recreate this normal anatomy. We reviewed the records of our TKR's from Jan 2008 to Dec 2010 and included all patients who had a normally functioning contralateral knee, tibial cut <3° from perpendicular to the mechanical axis performed by/under supervision of a single surgeon. These patients were contacted for follow up and axial flexed knee x-rays to measure femoral rotation and FFA (angle between clinical transepicondylar line and mechanical axis of tibia). These values were compared between replaced and normal knees using Students T-test.Background:
Methods:
The aim of the study was to assess the efficacy of a cementless acetabular cup without bone grafting in a cohort of patients with protrusio acetabuli who were treated with total hip arthroplasty. We retrospectively reviewed the records of a cohort of 45 patients with protrusio acetabuli who received elective total hip replacements between 2009 and 2011 at Tygerberg Academic Hospital. We reviewed pre- and post-operative radiographs and the most recent follow-up radiographs (minimum of three months) to assess cup osteointegration. We classified protrusio acetabuli according to Sotelo-Garza and Charnley into mild, moderate and severe, by evaluating pre-operative radiographs.Purpose
Methods
To assess acetabular component fixation by bone ongrowth onto a titanium plasma sprayed surface as used in revision total hip arthroplasty. Acetabular bone defects, a common finding in revision surgery, and their relation to outcome were also investigated. Clinical and radiological results were evaluated for all revision total hip replacements done between 2006 and 2011 that included the use of a specific revision acetabular component. Forty six hips in 46 patients were followed for an average of 2.5 years (range8 months to 6 years). The acetabular defects were graded according to Paprosky's classification.Purpose
Methods
The research question was: can Arthroscopic or open biopsies were obtained, with informed consent and institution-approved review protocol, from patients undergoing total shoulder replacement or orthopaedic interventions for end-stage rotator cuff deficiency or arthropathy. Chondrocytes were isolated from eight biopsies and cells cultured over 4-weeks. In the first week post-digestion, validation studies showed cell counts varying from 30 000 to 400 000 (mean 126 666) and viability ranging from 30% to 100% (mean 75.2%). No primary culture failures were observed. One of the eight had an unexplained lower cell count and viability. Viability exceeded 80% in six of the eight cultures (75%). Alcian Blue stains and flow cytometry (Facscan) confirmed stable cultures with matrix formation. Aggrecan studies are in progress. The fact that
Over a six-year period, one surgeon operated on 46 men with instability associated with antero-inferior glenoid loss. Thirty-three of them played rugby at a competitive level. The mean number of preoperative dislocations was five (2 to 22). Modifications included a change in orientation of the coracoid bone block and the addition of capsular closure. A Walch-Duplay score for instability was calculated at follow-up. The mean follow-up was 38 months with a minimum of 6 months. Only one patient had recurrent instability. Thirty-one returned to sport at the same level. Walch-Duplay scores were excellent in 70%, good in 25%, mild in 3.75% and poor in 1.25%. Complications included two fibrous unions (excellent outcome), three broken screws (excellent outcome) and two fixation failures owing to patient non-compliance. There was no decrease in the range of internal rotation. Eight patients had mild restriction in forward flexion (mean 5°) and 20 patients had mildly reduced external rotation at 90° abduction (mean 5°). All but one patient with recurrent dislocation rated the outcome excellent and would have the operation again. The Latarjet procedure confers outstanding stability and gives excellent subjective and objective outcomes.
The proximity of neural structures to the coracoclavicular ligaments limits the amount of coracoid process that can be harvested. The purpose of this study of 100 dry human scapulae was to define the anatomic limitations. We found the mean measurement of the horizontal arm of the coracoid process anterior to the conoid tubercle was 21.5 mm (SD 0.9 mm). In 10% of the scapulae, it was larger than 30 mm. In 66%, the posterior aspect of the conoid fused with the vertical ramus and the lateral lip of the suprascapular notch. This amount of coracoid appears to be large enough to expand the glenoid vault, and to hold two AO small fragment screws. It can be safely harvested if the conoid ligament is respected. Partial sacrifice of the trapezoid ligament is unavoidable, but does not compromise coracoclavicular stability. If the coracoid osteotomy is extended medial to the conoid tubercle it encroaches on the vertical ramus of the coracoid and can damage the suprascapular nerve. Posterior advancement of the osteotomy can extend onto the anterosuperior glenoid.
Between 1996 and 2001 we used a modification of the Latarjet procedure to treat 70 patients with bony insufficiency of the glenoid. Our modification involves detaching a long piece of coracoid and rotating it to match its concave inferior surface with the surface of the glenoid. The coracoid graft is placed extra-articularly and the capsule repaired with bone anchors to the edge of the glenoid. Postoperatively no sling is applied and rehabilitation is started early. At a mean of 24 months (9 to 72) patients were clinically reviewed and assessed on the Walch-Du Play score. The results were excellent in 68%, moderate in 6% and poor in 1%. There were no redislocations. The results were most satisfactory in this group of patients, most of whom participated in contact sports, where soft tissue procedures (e.g., open and arthroscopic Bankarts) carry unacceptable failure rates.
