Giles R. Scuderi

Surgical techniques in total knee arthroplasty

Introduction. 1: Preoperative Planning. 2: Surgical Approaches. 3: Correction of Deformity. 4: Bone Defects. 5: Patellar Preparation. 6: Patellar Tracking. 7: Component Position. 8: Instrumentation. 9: Fixation. 10: Prosthetic Choice. 11: Revision Arthroplasty. 12: Infection. 13: Extensor Mechanism Dysfunction. 14: Periprosthetic Fractures. 15: Classification of Bone Defects. 16: Other. 17: Extra-Articular Deformity in TKA. 18: Management of Soft Tissues and Previous Incisions. 19: Rehabilitation. 20: Arthroscopic Management of Problematic TKA. 21: Glossary of Implants.

Minimally invasive surgery in orthopedics

Minimally invasive surgery in orthopedics , Minimally invasive surgery in orthopedics , کتابخانه دیجیتال جندی شاپور اهواز

Minimally invasive knee arthroplasty: An overview

Minimally invasive surgery (MIS) for arthroplasty of the knee began with surgery for unicondylar knee arthroplasty (UKA). Partial knee replacements were designed in the 1970s and were amenable to a more limited exposure. In the 1990s Repicci popularized the MIS for UKA. Surgeons began to apply his concepts to total knee arthroplasty. Four MIS surgical techniques were developed: quadriceps sparing, mini-mid vastus, mini-subvastus, and mini-medial parapatellar. The quadriceps sparing technique is the most limited one and is also the most difficult. However, it is the least invasive and allows rapid recovery. The mini-midvastus is the most common technique because it affords slightly better exposure and can be extended. The mini-subvastus technique entirely avoids incising the quadriceps extensor mechanism but is time consuming and difficult in the obese and in the muscular male patient. The mini-parapatellar technique is most familiar to surgeons and represents a good starting point for surgeons who are learning the techniques. The surgeries are easier with smaller instruments but can be performed with standard ones. The techniques are accurate and do lead to a more rapid recovery, with less pain, less blood loss, and greater motion if they are appropriately performed.

Medial Release for Fixed-Varus Deformity

Varus deformity of the knee is one of the most common deformities seen at the time of total knee arthroplasty. When a fixed deformity is present, the pathoanatomy usually involves erosion of medial tibial bone stock with medial tibial osteophyte formation, and contractures of the medial collateral ligament (MCL), posteromedial capsule, pes anserinus, and semimembranosus muscle (Fig. 25.1). Elongation of the lateral collateral ligament is a late event. A flexion contracture may coexist, which is manifested by contractures of both posterior capsule and posterior cruciate ligament. Success and longevity of total knee arthroplasty is predicated in part on achieving proper limb alignment of 5 to 10 degrees of valgus.1 The limb should be corrected to this ideal alignment without regard to the contralateral alignment, because a varus deformity often exists bilaterally. Furthermore, the ideal alignment of the femoral component is 7 2 degrees of valgus angulation, whereas that of the tibial component is 90 2 degrees relative to the longitudinal axis of the tibia.1 The ideal alignment is achieved through soft tissue releases aimed at balancing the collateral ligaments, and by placing the components in the correct orientation. If the proper alignment is not achieved, or if the ligaments are inadequately balanced, the components will be overloaded medially and subjected to excessive stresses, which may result in the eventual failure of the arthroplasty via either component loosening or accelerated wear. Intraoperatively, it is imperative to reassess each step of the soft tissue release so as not to overcorrect the deformity and create valgus instability.

Lateral Release for Fixed-Valgus Deformity

Fixed-valgus deformity can be a challenging problem for the reconstructive surgeon. The normal knee is aligned with a femorotibial angle of 6 to 7 degrees of valgus, and the goals of knee replacement surgery include a painfree knee with normal alignment and functional range of motion. We believe a posterior-stabilized prosthesis with sacrifice of the PCL will provide more reliable results for most surgeons in the valgus knee. The surgical epicondylar axis provides a reliable and reproducible landmark for appropriate rotational alignment of the femoral component, whereas the less involved medial femoral condyle and tibial plateau should be used to reference the distal femoral and proximal tibial cuts. Soft tissue balance should be achieved without modification of bone cuts. Sequential releases should be reassessed intermittently with laminar spreaders or a tensor. Avariety of releases and sequences of release have been described, and our preferred method is described earlier in this chapter. Correctly balanced, 90 to 95% of patients with valgus deformity reportedly will have good or excellent results. Complications include peroneal nerve palsy, instability, and patellar maltracking.

Minimal Incision Total Knee Arthroplasty

Total knee arthroplasty (TKA) has evolved during the past 30 years to a well-defined technical surgery with excellent results for as many as 20 years of followup. The concepts of exposure, ligament balancing, and joint alignment have been established clearly by Insall and others. In the early 1990s, Repicci introduced minimally invasive surgery for unicondylar knee arthroplasty. This approach suggested that less invasive surgery could accomplish similar results to those of standard unicondylar knee arthroplasty. Early reports in the literature support these conclusions. It only was logical that the minimally invasive surgery approach eventually would be applied to TKA. It is extremely important to establish a clear definition of the minimally invasive surgery and, then, to follow the results. We have completed 70 minimally invasive TKAs during the past 9 months with early results that indicate less intraoperative blood loss, shorter length of stay, increased range of motion (ROM), with similar implant accuracy to standard TKA. These new procedureswill require thorough evaluation as with any new clinical endeavor. It also is of paramount importance to remember that the main goal of any new technology is to advance the science of medicine without compromising the ultimate result for the patient. The early findings are encouraging for the future of minimally invasive TKA and we hope to improve the technology during the next few years.

MIS of the Hip and the Knee

in press). 23. Pandit H, Jenkins K, Beard D, et al. Oxford Unicompartmental Knee Arthroplasty using a minimally invasive surgical approach—a multicentre prospective study. EFFORT Helsinki, 2003. 8. MIS: Oxford Unicompartmental Knee Replacement 159

Management of Patella Tendon Rupture

Rupture of the patella tendon during or following total knee arthroplasty (TKA) can be an extremely challenging complication to manage. The following case reports will describe several surgical options for the management of patella tendon ruptures, but it is important to identify those patients who are at greater risk for rupture of the patella tendon. Those patients at higher risk tend to be obese, have limited preoperative range of motion, have had prior surgery, or have a metabolic condition or connective tissue disorder that may compromise the patella tendon.

Round Table Discussion of a MIS Spine Surgery Case

The patient is a 23-year-old woman, who was doing well until she was thrown from her horse. Since then she has had excruciating low back pain, radiating into her buttocks, the lateral aspect of her thighs, and into her lateral calves bilaterally. Neurologic examination is normal. She has no other medical comorbidities. This pain has been going on for 1 year and has not responded to pain medication, physical therapy, bracing, epidural steroids, and chiropractic manipulations with anything other than partial, temporary relief. She wishes to proceed with some type of surgery.

Round Table Discussion of Mini-incision Total Hip Arthroplasty

Richard Berger: Many different minimally invasive total hip arthroplasty (THA) techniques have become popular in the last few years. Let’s start by defining what is a minimally invasive total hip arthroplasty? Is it a skin incision length, a soft tissue procedure, or a systematic approach to THA?