摘要:

The technique for revising a total joint arthroplasty is presented, with particular attention given to the initial exposure and the preparation of the distal femur and proximal tibia. The exposure is difficult in many cases. The quadriceps turndown technique, originally described by Coonse and Adams and modified by Insall, is presented. This technique greatly facilitates exposure and enables the distal femur and proximal tibia to be dissected free from overlying scar tissue. The technique of skeletonization of the bones is also presented. This technique provides adequate assessment of the existing bone stock prior to reimplantation of a new total knee replacement. These techniques have been successfully utilized in over 250 revision total joint arthroplasties at the Knee Service at The Hospital for Special Surgery.

ISSN:0885-9698    

出版商:OVID    

年代:1988

数据来源: OVID

摘要:

The quadriceps turndown procedure is an important part of the surgical armamentarium of the knee arthroplasty surgeon. In the knee contracted in extension, it provides distinct advantages for safe exposure, restoration of a functional flexion range, and facilitation of early postoperative rehabilitation. Close attention to detail during this procedure is imperative. Satisfactory resolution of extensor lag and restoration of a functional flexion range may be anticipated.

ISSN:0885-9698    

出版商:OVID    

年代:1988

数据来源: OVID

摘要:

Patellofemoral problems are the most common causes of reoperation following total knee arthroplasty. Complications include wear, loosening, stress fracture, and patellar instability. Of these, patellar instability may be the most frequent problem and can be difficult to treat. Multiple factors contribute to maltracking of the patella, including residual valgus limb alignment, patella alta, prosthetic design geometry, excessive valgus placement of the femoral component, malrotation of the femoral and tibial component, quadriceps contracture, capsular dehiscence, dynamic instability, failure to perform a lateral release, excessive patellar thickness, and asymmetric patellar bone preparation. Proper treatment involves determining the mechanism for instability to help choose the best surgical solution to the problem.

ISSN:0885-9698    

出版商:OVID    

年代:1988

数据来源: OVID

摘要:

The conainons or component positioning ana overall axial alignment tnat are important in primary and revision total knee arthroplasty and in addressing problems of malalignment and ligament incompetence are described. The component position description incorporates a simple tibiofemoral model with the tibia “suspended” via collateral ligaments. These ligaments are seen as originating from the femoral epicondyles, which can be thought of as the general neighborhood of the centers of rotation for flexion-extension movement. Ligament balancing by soft-tissue release, as well as by collateral ligament tightening, are discussed. The simpler techniques of soft-tissue release at the concave side of the deformity are the most common techniques for routine ligament balancing. Problems of component axial malalignment in the presence of stable ligaments; ligamentous instability in the presence of stable, well-aligned components; and frank tibiofemoral dislocation are also covered. A basic philosophy of avoiding, whenever possible, highly constrained implants is put forth, together with an emphasis on the idea of knowing when to move toward fusion as the operation of choice.

ISSN:0885-9698    

出版商:OVID    

年代:1988

数据来源: OVID

摘要:

Tethering of the patellar tendon with a resultant patella baja and hypertrophy of the infrapatellar fatty tissue are two rare causes of anterior knee pain after total knee arthroplasty. Symptoms are varied, with limitation of flexion due to anterior pain or pain during extension being the most common. Examination is not very helpful, except for the patella, which may have a rubbery feeling on transverse motion. Relief of discomfort by injecting a local anesthetic within the joint warrants an arthrotomy if conservative measures have failed to relieve symptoms. Surgical excision of the hypertrophied adipose and fibrous tissue and freeing of the quadriceps—patella—patellar tendon has been very effective in relieving pain and increasing motion.

ISSN:0885-9698    

出版商:OVID    

年代:1988

数据来源: OVID

摘要:

The lower extremity may be lengthened or shortened at the knee joint as the result of correcting deformity during arthroplasty. This tendency is probably greater with revision surgery.Fixed-flexion, varus, and valgus deformities may all be corrected with well-described surgical techniques. These techniques are based on specific beliefs about the pathology of soft tissues in the deformed knee. These techniques do not necessarily include maintaining normal limb length as a primary goal. With revision surgery, soft-tissue stability may eventually be lost, and prostheses with increased constraint will he necessary to stabilize the knee.

ISSN:0885-9698    

出版商:OVID    

年代:1988

数据来源: OVID

摘要:

Patellar tendon avulsion most frequently occurs following errors in surgical technique either during exposure of an ankylosed knee or following distal extensor mechanism realignment for lateral patellar subluxation or dislocation. Prevention of this complication is paramount as salvage is difficult. Protection of the repair for several months is indicated and late reconstruction is feasible in selected individuals.

ISSN:0885-9698    

出版商:OVID    

年代:1988

数据来源: OVID

摘要:

The chronically dislocated patella is usually associated with fixed valgus and often with fixed-tlexion deformities. All components of the deformity must be addressed to achieve a satisfactory result following total knee arthroplasty. The proper rotation of the tibial and femoral components is critical, and slight external rotation of either component will assist patellar tracking. Extensor mechanism realignment is performed proximally, usually with the “tube” realignment technique or occasionally with a Coonse-Adams extensor turndown technique. Distal extensor realignment is discouraged. Cemented implants are preferable; metal-backed patellar components should be avoided. Postoperative rehabilitation is modified to protect the extensor mechanism repair.

ISSN:0885-9698    

出版商:OVID    

年代:1988

数据来源: OVID

摘要:

Resurfacing of the patellofemoral joint is fraught wan many potential promems. Extreme care must, be used in the technical aspects of resurfacing. The thickness of the patella should be maintained. Asymmetric resurfacing should be avoided. Proper patellar tracking must be present throughout a range of motion. Metal-backed implants should be avoided. A biconvex patellar dome has proven to be a valuable technique for the management of patellar bone loss.

ISSN:0885-9698    

出版商:OVID    

年代:1988

数据来源: OVID

摘要:

The surgical correction for valgus deformities of the knee during total knee arthroplasty is described. Special attention is paid to the compensatory techniques used if undercorrection or overcorrection is present following the initial release and placement of trial components. At the completion of the arthroplasty, the knee should be balanced in both flexion and extension on both the medial and lateral sides so that one side is not so tight as to cause tilting of the femur. The sequence of the soft-tissue release is listed.

ISSN:0885-9698    

出版商:OVID    

年代:1988

数据来源: OVID