Resection arthroplasty of the hip.

The results of forty-eight resection arthroplasties (Girdlestone procedures) in forty-three patients were analyzed. The indications were sepsis after a total hip replacement (thirty-three procedures), aseptic loosening of a total hip replacement (ten procedures), and primary septic arthritis (five procedures). The resection arthroplasty effectively eradicated the sepsis in all but three patients, who had a recurrence. Pain was alleviated in nearly all of the patients, but the ability to walk and the level of activity improved only slightly. Shortening of the limb ranged from three to eleven centimeters, and all patients used a support for walking. The six patients who had a bilateral procedure were able to walk using double supports. With regard to relief of pain, walking, and function, the results were significantly poorer in the women, particularly the older ones. The results were also significantly inferior in the patients who had had sepsis after a total hip replacement. Generally, walking, function, and the level of activity were better when much of the proximal end of the femur had been retained. Resection arthroplasty should spare as much of the proximal end of the femur as possible if a future replacement of the hip is contemplated.

Porous surface replacement of the hip with chamfer cylinder design.

Fifty-seven porous surface replacements (PSR) were performed in 53 patients (36 men and 17 women) with a mean age of 54 years (range, 19-75 years). Follow-up examination times ranged from one year to 2.5 years with 33 patients having follow-up periods of at least two years. Preoperative diagnoses were osteoarthritis (OA), 37; osteonecrosis (ON), six; dysplasia, nine; rheumatoid ankylosing spondylitis, three; and other, two. Sixteen hips had metal-backed acrylic-fixed THARIES (total hip articular replacement by internal eccentric shells) acetabular sockets, nine hips had a cobalt chrome hemispherical beaded acetabular component with adjuvant screws, and 32 hips had a chamfer-cylinder designed acetabulum. Pain relief has been immediate and more complete than with acrylic-fixed or biologic-in-growth stem-type replacements with comparable walking and function improvements. There have been no major systemic complications, sepsis, or loosening. There have been two transient peroneal nerve palsies and three trochanteric fibrous unions. There has been one subluxation requiring reoperation. Histologic sections of the removed femoral surface component showed excellent (90%) bone ingrowth. Circumferential progressive radiolucencies developed at the bone-cement interface by one year in all of the 16 acrylic-fixed acetabular components. Reaming or seating defects were noted in 25% of the patients on postoperative radiographs. Serial radiographic analyses demonstrate progressive narrowing of all of the chamfered cylinder design and less in hemispherical design with screw fixation. These observations are encouraging and suggest healing of the bone-component interface with bony trabeculae in the porous-coated acetabular design. This new surface replacement (SR) of the hip uses porous-ingrowth fixation to overcome the major disadvantages of acrylic-fixed SR which are as follows: (1) excessive acetabular reaming, (2) poor long-term fixation, and (3) difficulty with acetabular revision.

THARIES resurfacing arthroplasty. Evolution and long-term results.

The unsatisfactory results of total hip arthroplasty in the young patient led to the development of the concept of hip resurfacing. Total hip articular replacement by internal eccentric shells (THARIES) resurfacing was introduced in 1975, with the primary goal of bone stock preservation and the hope of increased durability in the young patient. Major changes in design and technique include thicker and more uniform acrylic layers, metal-backed flanged acetabular component, and reduction in femoral size for preservation of acetabular bone stock. Of the 584 hips (average patient age, 48 years) with one- to ten-year follow-up study, there have been 72 failures (revision rate, 12.3%) with 66 cases of loosening (nearly all beginning in or limited to the acetabular side), two neck fractures, and four sepses. Survivorship analysis revealed that the single most important factor related to prosthesis failure is age followed by diagnosis and experience of the surgeon. Osteoarthritis and rheumatoid arthritis were favorable categories with congenital dysplastic hip (CDH), osteonecrosis, and previous failed resurfacing being unfavorable categories. Experience has taught the importance in preserving acetabular bone stock, providing bone graft for socket coverage in severe dysplasia, and removing dead bone in osteonecrosis. While resurfacing did not solve the problems of the young patient, even those patients who failed often gained time for application of the newer techniques and materials. The femoral component infrequently failed. The head remained vascular. This leads the authors to conclude that the surface arthroplasty concept is a viable alternative to total hip arthroplasty and seems to be ideal for the application of porous technology.

Canine porous resurfacing hip arthroplasty. Long-term results.

Long-term experimental data support the hypothesis that biologic bone ingrowth into porous surfaces in a hip-resurfacing model is a viable alternative to stem-type porous implants. Ingrowth of bone was demonstrated in long-term canine arthroplasty. The components were well fixed and stable at the time of sacrifice, although ingrowth occurred to varying degrees. The ingrowth and quality of remodeling was influenced by stress. Dislocations were overcome by a change in surgical technique. Loosening and neck fractures were associated with insufficient stability at operation or to component impingement (prevented by modifications of design). The formation of metal debris-filled cysts is a concern and appeared to be associated with the poor quality of porous sintering and possibly abrasion. The effects of increased surface area of the porous components such as increased corrosion products on biologic compatibility are still not well defined and require further research and longer follow-up examination.

Comparative experience with canine and human cementless acetabular components.

Bone ingrowth in the porous canine implants does occur; the early clinical results are indeed encouraging and justify further investigation. The quality of ingrowth as measured by depth and extent in the dog was stress-related. Remodelling was superior in the more compliant or elastic acetabular components without an interposed metal shell. No human specimens have been retrieved thus far, but we are encouraged because the results in the canine model with acrylic-fixed implants were comparable to the results we subsequently observed in human THARIES implantation. Those were initially excellent, but with time radiolucencies increased and loosening occurred. The quality of the canine biologic ingrowth suggests optimism for secure and durable fixation. Our patients have continued to improve through the follow-up period. There has not been a single case in which a qualitative increase in pain occurred over the cemented versions after operation. The technical problems of the surgical procedure have been overcome, but it must be performed precisely to achieve the initial inherent stability to assist in biologic ingrowth. The operative procedures in this series have been performed by or under the direct supervision of the senior author. As our competence has grown, we have applied the procedure to younger patients and those who have bone stock deficiency. One of the major advantages of the biologic ingrowth systems is the facility to graft cysts and defects. For humans, the current chamfered cylinder is an extremely bonestock-conservative procedure when combined with reaming of the femoral head to the neck size. Although space is limited in resurfacing, we have been able to achieve a minimum 4-mm bearing thickness of polyethylene. We believe that the compliant mesh chamfered cylinder system provides excellent stability. However, the hemispheric component, although technically more difficult to seat and fix, has definite applications in bonestock deficiency and with further refinement will be useful in primary replacements as well. Nevertheless, because of the uncertain future of any type of implant, especially new, we have encouraged the patients to follow a careful postoperative management program and refrain from heavy activity during the first year. Many are active and some are now participating in athletics, although this is certain to shorten the life of these implants just as was observed in acrylic-fixed devices. The biologic problems of interface corrosion, migration, and metal ion transfer indicate that these implants must be followed for longer periods. Therefore it seems unwise to extend this technology to a wide clinical use at this time.

A technique of medial ligament repair of the knee with cancellous screws and spiked washers.

Twenty-five cases of proximal and distal tears and avulsions of the medial ligament of the knee were repaired under tension using cancellous screws and spiked washers with a mean follow-up period of 11.2 months. All knees were submitted to 15 Kp lateral stress in 20 degrees of flexion and radiographs in this position compared with those of the opposite knee. All patients were reassessed clinically and radiologically when stressed with the Telos apparatus. Radiographic instability was demonstrated in four cases. We conclude that cancellous screws and spiked washers, applied correctly, provide better fixation than other described methods and give a satisfactory repair of the torn ligament.

Arthroscopic surgery of the knee.

In the first 1000 arthroscopic operations performed by one surgeon 136 patients had two or more procedures, making a total of 1168 during the 1000 operations. The indications for operation were internal mechanical derangements in 565 patients, anterior knee pain in 246, disorders of the synovium in 77, ligament injuries in 63, and degenerative joint disease in 49. Complications included fracture of instruments in the knee in five patients, haemarthrosis in 10, deep vein thrombosis in three, and synovial fistula in one. In no patient was the wound infected. A total of 26 different operations was performed.

Open reduction and percutaneous Kirschner wire fixation in complete disruption of the acromioclavicular joint.

Open reduction and percutaneous Kirschner wire fixation was carried out in 35 patients who had sustained recent Allman type 3 dislocations of the acromioclavicular joint. At follow up, failure to maintain reduction had occurred in two patients, both over 55 years. All younger patients had returned to former sporting activities. Complications encountered were infrequent. Cosmetic results were satisfactory.