Effect of External Sequential Compression Devices on Femoral Venous Blood Flow--David C. Markel, MD, Gary D. Morris, MD
Sequential compression devices are used to reduce venous stasis and deep venous thrombosis after joint replacement. Thigh-length, calf-length, and foot compression devices were compared in using ultrasonography after unilateral knee arthroplasty. Simulated muscle activity via active ankle motion was also evaluated. Blood flow volume and velocity were recorded above and below the saphenous vein bifurcation, the division of the superficial and deep systems, allowing evaluation of each. Volume and velocity increased in the superficial and deep systems with all devices. A control group was evaluated to determine differences related to age and surgery. The devices performed similarly in the volunteers. However, active motion performed better than any device. Thus, unlike young, healthy patients, muscle activity alone in the operative population was unreliable in increasing blood flow. Thigh-length, calf-length, and foot compression devices are are effective at increasing femoral blood flow volume and velocity in the deep and superficial venous systems after total knee arthroplasty
Biomechanical Comparison of Reconstruction Techniques for Disruption of the Acromioclavicular and Coracoclavicular Ligaments--Albert W. Pearsall IV, MD;Â J. Marcus Hollis, PhD;Â George V. Russell, Jr., MD;Â David A. Stokes, MD
Injuries to the acromioclavicular joint are common. For selected injuries, operative reconstruction is recommended. The purpose of the current study was to compare three reconstruction procedures: (1) nine strands of woven polydioxanonsulphate (PDS II) suture passed through the clavicle and around the coracoid; (2) procedure No. 1 with 50% of the coracoacromioclavicular ligament placed through 2 clavicular drill holes; (3) No. 5 Merselene tape passed through 2 drill holes in the clavicle and acromion, with 50% of the coracoacromial ligament transferred to the clavicle. Fourteen fresh frozen human shoulders were tested using a 6 degree-offreedom testing device. The intact shoulder showed significantly less displacement than any of the reconstructions. Merselene tape plus ligament showed the largest displacement, and PDS II braid plus ligament showed the least displacement. None of the procedures reconstituted acromioclavicular joint stiffness to intact state levels, though improved acromioclavicular joint stiffness was noted with a PDS braid plus ligament.
Radiographic Evaluation of Periprosthetic Metallosis After Total Knee Arthroplasty--Thomas F. McGovern, MD;Â Joseph T. Moskal, MD
This retrospective study examined the clinical significance of a radiographic sign associated with periprosthetic metallosis after total knee arthroplasty. Of 71 knees undergoing revision arthroplasty over an 8-year period, 11 had gross evidence of metal debris identified intraoperatively. Histologic preparations confirmed the presence of particulate metal debris in all cases. Radiographs in 7 of 11 cases were positive for metallosis. The radiographic sign identified on lateral radiographs was divided into 3 types based on the size of the mass. The magnitude of soft tissue pathology and the extent of osteolysis correlated with the size of the mass on preoperative radiographs. Replacement of all components was necessary in 71% of cases with radiographs positive for metallosis and 47% of cases with negative radiographs. Only 1 of the 11 knees with metallosis had a late postoperative infection, for which 2-stage revision arthroplasty was required. All cases with positive radiographs had gross and histologic confirmation of metal and polyethylene debris. These data suggest that careful assessment of radiographs can facilitate preoperative planning.
Revision Anterior Cruciate Ligament Reconstruction Surgery--Robert S. Wolf, MD;Â Lawrence J. Lemak, MD
In 1995, it was reported that 60,000 to 75,000 anterior cruciate ligament (ACL) reconstructions were being performed annually in the United States. Successful long-term results are achieved in 75% to 95% of these patients, but 8% have unsatisfactory results due to recurrent instability and graft failure. With the increasing popularity of this procedure, ACL revision surgery has also become increasingly common. While the techniques described for ACL revision have been varied, the overall results in the literature do not compare favorably with primary ACL reconstruction. The proper execution of revision ACL reconstruction requires precise preoperative planning to assess the cause of initial failure and avoid repeating the same mistakes with revision reconstruction. Graft choice, hardware removal, revision notchplasty, tunnel placement, and method of fixation are key points for a successful result. The causes of ACL failure, the technical aspects of revision ACL surgery, and the reported results of revision ACL surgery are reviewed.
Fresh Osteochondral Grafting in the Treatment of Osteochondritis Dissecans of the Talus--Mark T. Caylor, MD;Â Albert W. Pearsall IV, MD
We present a review of the literature on classification and treatment of osteochondral defects of the talus. We report the case of an isolated Berndt and Harty grade II lesion treated with a fresh osteochondral allograft. We believe that fresh allograft osteochondral grafting of the talus is an excellent technique for symptomatic Berndt and Harty grade II or higher lesion of the talus without significant tibiotalar arthritis. In selected patients, this procedure can provide excellent functional results.