Periprosthetic fractures occurring in total shoulder arthroplasty (TSA) represent challenges both in decision-making as well as surgical management. These fractures more frequently involve the humerus but can also occur in the scapula. In a few cases with minimal displacement conservative care may be employed. In most, however, surgical intervention is needed. Depending on the quality of the surrounding bone, the health of the patient, the stability of the existing implant, and the integrity of the surrounding soft tissues, options for management include open reduction and internal fixation, long stem implants, bone grafting, strut and cable fixation, or a combination of these techniques. In some cases revision arthroplasty is indicated. An approach to surgical decision-making, operative techniques and avoidance of complications will be presented.
In an effort to address the relatively high rate of glenoid component lucent lines, loosening and failure, tantalum/trabecular metal glenoid implant fixation has evolved as it has in hip and knee arthroplasty. Trabecular metal-anchored glenoid implants used in a consecutive patient case series have demonstrated a lower failure rate than traditional all polyethylene cemented glenoids. Although the radiographs of some patients demonstrated small focal areas of lucency, none have become loose, and only two have actually demonstrated glenoid component failure due to a fracture 6 years after the index procedure. One with glenoid loosening was due to polyethylene wear from a massive cuff tear occurring 8 years after the index procedure. Most patients experienced significant improvements in shoulder range of motion and reduction in pain. Trabecular metal-anchored glenoids when carefully implanted do not produce excessive failure rates, but rather result in functional improvements while decreasing operative time.
The age spectrum for patients undergoing shoulder arthroplasty is broadening. Many younger patients now demonstrate shoulder pathology precluding non-arthroplasty reconstruction. The senior population is living longer and “younger”. Therefore, the demands of this patient population to participate in an active lifestyle are growing. Patients with osteoarthritis, cuff tear arthropathy, post-traumatic arthropathy, avascular necrosis, and even forms of inflammatory arthropathy present seeking not only return to simple activities of daily living but the ability to participate in aerobic recreational activities and even work activities which can stretch the limits of shoulder arthroplasty in the physiologic environment of the shoulder. This presentation will provide an overview of patient demands, concerns and activity level following shoulder arthroplasty. We will provide a prospective of allowable, recommended and discouraged activities depending on the underlying source of pathology in the type of arthroplasty implants employed. An overview of our four phases of rehabilitation protocol will be presented focusing on phase four, “work in sports hardening”.
Experience has demonstrated in the hip and knee, related to total joint replacement arthroplasty, polymethyl methacrylate cement fixation can provide problems in terms of loosening, fragmentation, particulate wear and ultimate failure. These same problems have been recognised in total shoulder arthroplasty related to cement fixation of the glenoid. While cement fixation of the humeral component has proven much less problematic, there has been a swelling towards avoidance of using cement to secure the humeral component for fear of difficulty if revision is required. Surprisingly, with the high incidence of lucent lines, bone resorption and frank loosening, representing the most common source of failure in total shoulder arthroplasty, cementless fixation of the glenoid has not been, until now, embraced. The advent of reverse total shoulder arthroplasty has demonstrated the ability for secure cementless fixation to provide long-lasting secure implant retention in implants which have inherently higher shear and stress forces passing through the implant/bone interface. In anatomic total shoulder arthroplasty a woven tantalum anchor (Trabecular Metal) has proven to demonstrate secure cementless fixation as well. This presentation will discuss the use of trabecular metal anchored glenoid implants with and without additional screw fixation for anatomic and convertible reverse arthroplasty baseplates. Avoidance of complications with successful long-lasting outcomes requires meticulous surgical attention to detail.
Peri-prosthetic fractures occurring in total shoulder arthroplasty represent surgical challenges both in decision making as well as surgical management. These fractures can involve both the humerus and scapula. In a few cases with minimal displacement conservative care may be employed. In most, however, surgical intervention is needed. Depending on the quality of the surrounding bone, the health of the patient, the stability of the existing implant, and the integrity of the surrounding soft tissues, options for management include open reduction and internal fixation, bone grafting, strut and cable fixation, or a combination of these techniques. In some cases revision arthroplasty is indicated. An approach to surgical decision-making, operative techniques and avoidance of complications will be discussed.
A variety of challenging shoulder pathology will be presented to a panel of expert shoulder surgeons for their diagnostic evaluation, decision making, surgical management and aftercare. They will discuss the decision making processes and management options to consider in striving to obtain optimal outcomes.
Cement fixation of the glenoid implants in total shoulder arthroplasty has been the norm since the procedure has existed. Yet, an unacceptably high rate of lucent lines, representing prosthetic loosening, and a high rate of resultant failure of fixation of these implants continues to be the single most common cause for revision surgery in total shoulder arthroplasty. Dissatisfaction with a higher than acceptable rate of lucent lines, cement fixation of the glenoid component has led us to evaluate and employ an implant anchored into the glenoid vault with a woven tantalum (trabecular metal) fixation stem. We have employed this implant in patients with healthy bone stock with a minimum 2-year follow-up in well over 100 cases with only one revision performed in a first generation implant due to fatigue fracture. No cases have demonstrated lucency or loosening. The procedure does require meticulous attention to detail to ensure precise surface and glenoid vault preparation providing complete intraosseous seating of the trabecular metal anchor and flush apposition and support of the polyethylene surface upon the face of the glenoid. This process has reduced surgical preparation time as well as time required for cement setting by an average of 20 minutes per case.
A panel of experts in the field of shoulder surgery/arthroplasty will be presented challenging case studies. They will discuss, dissect and analyze these cases from the perspective of appropriate work-up, clinical management, surgical approach and aftercare. A variety of cases representing the spectrum of pathology not uncommonly presenting to the surgeon caring for complex shoulder conditions will be discussed. Indications for nonsurgical and surgical interventions with consideration for various forms of arthroplasty will be presented and debated by the panel.
Hybrid fixation of total joint arthroplasty has been an accepted form of surgical approach in multiple joints. Principles of implant fixation should focus on durability providing secure long-term function. To date there is no conclusive evidence that pressed fit humeral stem fixation has an advantage over well-secured cemented humeral fixation. In fact, need for revision arthroplasty due to inadequate implant fixation has almost universally revolved around failure of cement fixation and loosening of the glenoid component. A case will be made based on 30 years of experience of one surgeon performing total shoulder arthroplasty using secure modern cement fixation techniques of humeral components. More recently, over the last 10 years, extremely high rate of durable secure glenoid implant fixation has been achieved using tantalum porous anchorage with polyethylene glenoid components. This has resulted in no cases of loosening of glenoid fixation and only 1 case of glenoid component fracture with greater than 95% survivorship over a 10 year period. A combination of well cemented humeral stem and trabecular metal anchorage of the glenoid has provided durable lasting function in primary total shoulder arthroplasty.
The key to management of instability when performing total shoulder arthroplasty is to recognise the potential for instability, and avoid the pitfalls which may lead to it post-operatively. Instability can result from incompetent capsular or rotator cuff soft tissue envelopes. It may also result from muscular imbalances, as well as incompetent bony architecture (severe posterior wear causing extreme retroversion, or anterior glenoid loss from fracture) extreme retroversion or improper placement or fixation of implants. Keys to providing a stable environment include performing careful soft tissue releases and providing muscular balance about the reconstructed arthroplasty; placement of implants in proper version; appropriate tensioning (height) and sizing (avoiding undersizing or overstuffing) of implants; recognizing incompetent rotator cuff substance or function and providing more stable, constrained implants (reverse total shoulder arthroplasty), when necessary. Keys to recognizing potential instability, tips and pearls for intra-operative and post-operative surgical management will be provided.
The importance of mitigating pain for patients undergoing total shoulder arthroplasty is extremely relevant for purposes of being able to initiate early functional rehabilitation and activities of daily living. The process, however, does not commence after surgery but rather before surgery. Careful patient education and instruction, including pre-operative exercises to maximise mobility, strength and endurance within the limited range of motion is quite helpful. Adjunctive therapy includes preemptive ultrasound-guided intrascalene regional anesthesia, immediate post-operative peri-incisional injection of liposomal bupivacaine, post-operative use of waterproof TegadermTM dressing to allow warm showers early on in the rehabilitation period, peri-operative use of Cox 2 inhibitors and a gentle, therapist-guided passive exercise program focusing on relaxation techniques. This in combination with patient-controlled analgesic pumps, careful surgical technique providing adequate soft tissue releases and removal of potential pain generators such as the long tendon of the biceps and an arthritic AC joint all contribute to the minimization of the patient's pain experience, and offers relatively early weaning from parenteral narcotics in the first 24 hours, and oral narcotics within the first 7–10 days post-operatively.
Retroversion, also referred to as posterior wear of the glenoid, can make resurfacing the glenoid challenging. However, careful pre-operative planning with three dimensional CT scanning can allow central placement of the glenoid component through removal of some of the anterior bone to allow contained placement and secure fixation within the glenoid vault. Since the scapula is not a fixed skeletal structure and moves substantially on the chest wall, the actual degree of posterior wear (retroversion) frequently is the result of extraneous biomechanical forces and structures. For example, the degree of kyphosis and shape of the rib cage can have a substantial impact on the relative position of the glenoid surface as it articulates with the humerus. Attempts to totally equalise this through implant augmentation have not, to date, been shown to be effective, and in some cases can be destabilising. Restoration of enough alignment to place the implant centrally can be achieved without need for augmentation even in some very hypoplastic glenoids. The technique for this straight-forward approach will be presented, including pre-surgical planning, in some cases, patient specific instrumentation, with demonstration of functional outcomes.
Total shoulder arthroplasty has been shown to be a very effective means of restoring function in all forms of arthritic shoulders. However, much as with any form of arthroplasty, problems and complications can and do occur. These include infection, nerve injury, anesthetic complications, peri-prosthetic fracture, instability and dislocation, nerve and vascular injury, loosening, loss of mobility, and contracture or stiffness, and implant related failures. Careful pre-operative planning, intra-operative technical execution, and post-operative rehabilitation all designed to meet the needs and demands of the specific patient can help identify potential sources of complications pre-operatively and avoid them post-operatively. Understanding the specific complexities of the type of arthritis being addressed, the strengths and weaknesses, limitations and need for adjustments to the local anatomy can help the surgeon execute the total shoulder arthroplasty with minimal likelihood for post-operative complications. Awareness of patient's own flora and application of appropriate antibiotic prophylaxis can help identify patients at risk for infection. Although it is impossible to fully eliminate the occurrence of complications, a majority can be avoided through attention to detail.
