Yadin D. Levy

14-Year Median Follow-Up Using the Press-Fit Condylar Sigma Design for Total Knee Arthroplasty

Median 14-year follow-up (mean 11.8 years) of a cemented primary posterior cruciate-retaining total knee arthroplasty (TKA) utilizing the Press-Fit Condylar (PFC) Sigma design was evaluated in 77 patients (79 TKA). Follow-up assessment included implant survivorship, x-rays, Knee Society rating system, and clinical evaluation. Radiographic analysis demonstrated minor non-progressive osteolysis in 40% (10/25) knees. Two revisions, one for instability at 4 years and one for polyethylene wear at 10 years were performed. Survivorship of the PFC Sigma knee implant was 97% using revision for any reason and 100% using aseptic loosening as endpoints. The PFC Sigma had excellent survivorship at 14 years, the longest clinical follow-up reported.

Thrombosis Incidence in Unilateral vs. Simultaneous Bilateral Total Knee Arthroplasty with Compression Device Prophylaxis

This study compares the incidence of venous thromboembolic event (VTE) in 55 patients (110 knees) undergoing simultaneous bilateral TKA with 287 patients (287 knees) undergoing unilateral TKA using a mobile compression device as monotherapy prophylaxis in both groups. All patients were clinically evaluated 3months after surgery with symptomatic confirmed VTE as an endpoint. Deep venous thrombosis (DVT) was documented by duplex ultrasound and pulmonary embolism (PE) was documented by spiral CT. The simultaneous bilateral TKA group had 6 VTEs (10.9%) with 2 PEs (3.6%). The unilateral TKA group had 9 VTEs (3.1%), and 0 PE. Patients undergoing simultaneous bilateral TKA yielded more than twice the rate of VTE compared with patients undergoing unilateral TKA using a mobile compression device as sole thromboprophylactic modality.

Poor Short Term Outcome with a Metal-On-Metal Total Hip Arthroplasty

Metal-on-metal (MoM) bearings for total hip arthroplasty (THA) have come under scrutiny with reports of high failure rates. Clinical outcome studies with several commercially available MoM THA bearings remain unreported. We evaluated 78 consecutive MoM THAs from a single manufacturer in 68 patients. Sixty-six received cobalt-chrome (CoCr) monoblock and 12 received modular titanium acetabular cups with internal CoCr liners. Femoral components were titanium with modular necks. At average 2.1 years postoperatively, 12 THAs (15.4%) demonstrated aseptic failure (10 revisions, 2 revision recommended). All revised hips demonstrated capsular necrosis with positive histology reaction for aseptic lymphocytic vasculitis-associated lesions/adverse local tissue reactions. Prosthetic instability following revision surgery was relatively common. Female gender was a strong risk factor for failure, though smaller cups were not. Both monoblock and modular components fared poorly. Corrosion was frequently observed around the proximal and distal end of the modular femoral necks.

Increase in Benign Squeaking Rate at Five-Year Follow-Up: Results of a Large Diameter Ceramic-on-Ceramic Bearing in Total Hip Arthroplasty

BACKGROUND Squeaking is an on-going complication with a variable incidence of 0.5%-20.7%. The mechanism of squeaking has not been understood completely and is most likely multifactorial in nature. Previously, we have reported on a squeaking rate of 7.3% at 2 years. Our current results show a substantial increase in the squeaking incidence from 7.3% to 17.4% with the DeltaMotion articulation at the 5-year follow-up. METHODS Two hundred six total hip arthroplasties with a large ceramic-on-ceramic bearing were performed on 195 patients by 2 senior authors. The minimum duration of follow-up was 5 years (range 5-6.2). RESULTS The mean Harris Hip Score remained stable at 91.7 at 5 years compared to 92 after 2 years. However, we observed an increase in the squeaking rate from 7.3% after 2 years to 17.4% after 5 years. As in previous studies, we did not find significant differences between the silent and squeaking group in relation to age, height, weight, and femoral head diameter. In contrast, others reported no significant differences regarding range of motion and gender between the silent and the squeaking hip group at 2 years of follow-up, whereas at 5 years, the squeaking group showed a significantly higher combined range of motion and a higher relative risk of squeaking in women compared to the silent group. CONCLUSION While large diameter ceramic bearings may produce squeaking, especially in female patients, our mid-term clinical results of a large ceramic-on-ceramic bearing in total hip arthroplasty are encouraging. Nevertheless, long-term follow-up is recommended.

Glenoid Rim Anatomy: Risk for Glenoid Vault Perforation During Labral Repair.

Background: Injuries to the glenoid labrum frequently require repair with anchors. Placing anchor devices arthroscopically can be challenging, and anchor malpositioning can complicate surgical outcomes. Purpose: To determine the safe insertion range and optimal insertion angle of glenoid labral anchors at various positions on the glenoid rim and to establish surgical guidelines that minimize risk of anchor perforation. Study Design: Descriptive laboratory study. Methods: Three-dimensional computed tomography scans of 30 normal cadaveric specimens were obtained. A virtual model of a generic labral anchor was inserted into the rim of the glenoid at the clockface positions represented by 12:00, 1:30, 3:00, 4:30, 6:00, 7:30, 9:00, and 10:30. At each position, the safe insertion range was the maximal range measured, and the optimal insertion angle was identified as the angle between the bisector of the safe insertion range and the glenoid face. Results: Progressing in the clockwise direction, beginning at the 12:00 position, the safe insertion ranges (mean ± SD ) were 55.9° ± 10.6°, 63.6° ± 17.6°, 47.7° ± 9.1°, 46.1° ± 8°, 73.9° ± 9.7°, 40.9° ± 6.5°, 40.4° ± 7.4°, and 39.9° ± 7.1°, respectively. The optimal insertion angles were 47.9° ± 7.6°, 53.1° ± 10.9°, 35.0° ± 4.4°, 42.4° ± 4.9°, 60.9° ± 8.4°, 36.6° ± 5.9°, 31.2° ± 4.9°, 34.8° ± 4.6°, respectively. Conclusion: Optimal insertion angles and safe insertion ranges varied significantly with respect to the position on the glenoid face. The safe insertion range and optimal insertion angle were found to be wider at the anterior glenoid as compared with the posterior glenoid. A posterolateral insertion angle was safer than an anterior insertion angle at the 10:30 position. Clinical Relevance: Proper arthroscopic technique resulting in anchor insertion at the correct angle, depth, and location will prevent anchor-related glenohumeral complications such as glenoid perforation, cartilage damage, persistent pain, decreased range of motion, and failure of the reconstruction.

Complications of Ceramic-on-Ceramic Bearings: Fracture, Stripe Wear, and Squeaking

Ceramic-on-ceramic (CoC) articulations were developed as an alternative bearing to conventional metal-on-polyethylene (MoP) bearings in order to decrease bearing surface wear and hopefully increase implant longevity. Overall, CoC bearings have the lowest rate of wear among all bearing [1] surfaces and are not associated with complications such as osteolysis and tissue necrosis linked with MoP and metal-on-metal (MoM) articulations, respectively. Despite ceramics’ superior tribological properties, their use has been associated with other complications such as fracture, edge loading, and squeaking. Edge loading and benign squeaking have little clinical significance, while pathological squeaking and fractures are rare. Despite the low rate of clinical complications seen, these factors deter surgeons from routinely using ceramic bearings in total hip arthroplasty (THA). This chapter further expands on these complications.