Failure of the Agility total ankle replacement system and the salvage options.

The Agility total ankle replacement system was the most commonly performed implant in the United States for more than 20 years and has undergone four generations and seven phases of improvement. Much attention has been placed on intraoperative complications, such as malleolar fracture; nerve or tendon injury; and incision healing-related problems, such as wound coverage and infection. However, it is the intermediate- and long-term complications (ie, aseptic osteolysis, subsidence, component loosening, and progressive malalignment) that require careful consideration, because the revision options remain limited. This article reviews the history of the Agility total ankle replacement system in detail, to understand the revision possibilities available.

History of total ankle replacement.

Attempts at ankle replacement have existed for at least 50 years. Time has essentially eliminated constrained, cemented, first-generation ankle replacements. Although some two-component, more anatomic, designs are still used with varying success, three-component "mobile bearing" ankle prostheses are winning the race of evolution. Not only have implants change over the years, but also the patients and surgeons. Surgeons specialize, improving their surgical outcomes and expanding the indications for total ankle replacement in technically demanding complex ankles. High-demand, younger patients, but also obese ones, are potential candidates for a total ankle replacement. This article provides a review of the history of total ankle replacement.

Biographical sketch: Themistocles Gluck (1853-1942).

This biographical sketch on Themistocles Gluck corresponds to the historic text, The Classic: Report on the positive results obtained by the modern surgical experiment regarding the suture and replacement of defects of superior tissue, as well as the utilization of re-absorbable and living tamponade in surgery (1891), available at DOI 10.1007/s11999-011-1837-7 .

Evolution of the reverse total shoulder prosthesis.

Over the last decade, reverse total shoulder arthroplasty has gained significant popularity due to its ability to address difficult reconstructive shoulder problems that could not be adequately treated in the past. The concept of the reverse shoulder prosthesis was introduced in the 1970s, but the initial attempts were associated with high complication and implant failure rates. The pioneering work of Paul Grammont (shifting the center of rotation medially and distally) and the development of the DELTA prosthesis have been fundamental to all subsequent reverse shoulder arthroplasty systems. These semiconstrained prostheses utilize the deltoid to improve function and stability of the shoulder joint by coupling a convex glenoid with a concave humeral component. Modern generations of reverse shoulder prosthesis continue to evolve on the fundamentals of Grammont. Though results of these new prosthesis demonstrate promising outcomes, many controversies and challenges continue to be refined. An historical review of the evolution of reverse shoulder arthroplasty is presented, as well as the currently expanding indications for its application.

Grammont's idea: The story of Paul Grammont's functional surgery concept and the development of the reverse principle.

BACKGROUND: The increased use of the reverse prosthesis over the last 10 years is due to a large series of publications using the reverse prosthesis developed by Paul Grammont. However, there is no article reporting the story of the concepts developed by Grammont. QUESTIONS/PURPOSES: The purposes of this review are to describe the principles developed by Grammont, the chronology of development, and the biomechanical concepts and studies that led to the current design of the reverse prosthesis. METHODS: We selectively reviewed literature and provide personal observations. RESULTS: From phylogenetic observations, Grammont developed the principle of functional surgery applied to the rotator cuff tears. To increase the deltoid lever arm, he imagined two possibilities: the lateralization of the acromion, which facilitates the action of the rotator cuff, and the medialization of the center of rotation, which has been developed to respond to situations of rotator cuff deficiency. Grammont proposed the use of an acromiohumeral prosthesis, which was quickly abandoned due to problems of acromial loosening. Finally, Grammont used the principle of reverse prosthesis developed in the 1970s, but made a major change by medializing the center of rotation in a nonanatomic location. In 1985, Grammont validated the concept by an experimental study and the first model using a cemented sphere was implanted. CONCLUSIONS: The development of the modern reverse prosthesis is the result of the intellectual and experimental work conducted by Grammont and his team for 20 years. Knowledge of this history is essential to envision future developments.

A history of reverse total shoulder arthroplasty.

BACKGROUND: Management of the cuff-deficient arthritic shoulder has long been challenging. Early unconstrained shoulder arthroplasty systems were associated with high complication and implant failure rates. The evolution toward the modern reverse shoulder arthroplasty includes many variables of constrained shoulder arthroplasty designs. QUESTIONS/PURPOSES: This review explores the development of reverse shoulder arthroplasty, specifically describing (1) the evolution of reverse shoulder arthroplasty designs, (2) the biomechanical variations in the evolution of this arthroplasty, and (3) the current issues relevant to reverse shoulder arthroplasty today. METHODS: Using a PubMed search, the literature was explored for articles addressing reverse shoulder arthroplasty, focusing on those papers with historical context. RESULTS: Results of the early designs were apparently poor, although they were not subjected to rigorous clinical research and usually reported only in secondary literature. We identified a trend of glenoid component failure in the early reverse designs. This trend was recognized and reported by authors as the reverse shoulder evolved. Authors reported greater pain relief and better function in reverse shoulder arthroplasty with the fundamental change of Grammont's design (moving the center of rotation medially and distally). However, current reports suggest lingering concerns and challenges with today's designs. CONCLUSIONS: The history of reverse shoulder arthroplasty involves the designs of many forward-thinking surgeons. Many of these highly constrained systems failed, although more recent designs have demonstrated improved longevity and implant performance. Reverse shoulder arthroplasty requires ongoing study, with challenges and controversies remaining around present-day designs.

History of cervical disc arthroplasty.

Enthusiasm for cervical disc arthroplasty is based on the premise that motion-preserving devices attenuate the progression of adjacent-segment disease (ASD) in the cervical spine. Arthrodesis, on the other hand, results in abnormal load transfer on adjacent segments, leading to the acceleration of ASD. It has taken several decades of pioneering work to produce clinically relevant devices that mimic the kinematics of the intervertebral disc. The goal of this work is to trace the origins of cervical arthroplasty technology and highlight the attributes of devices currently available in the market.

Historical development of alloplastic temporomandibular joint replacement after 1945 and state of the art.

The variety of temporomandibular joint (TMJ) prostheses and condylar reconstruction plates available is in contradiction to their rare application. This emphasizes that alloplastic TMJ reconstruction is still evolving. This article reviews the history of TMJ reconstruction. Medline as well as public and private libraries have been searched. Current systems are reviewed. Prosthetic devices can be differentiated into fossa-eminence prostheses, ramus prostheses and condylar reconstruction plates, and total joint prostheses. Fossa and total joint prostheses are recommended when the glenoid fossa is exposed due to excessive stress (degenerative disorders, arthritis, ankylosis, multiply operated pain patients). Singular replacement of the condyle is preferred as a temporary solution in ablative surgery. The use of prosthetic devices for long-term replacement should be restricted to selected cases, taking care to retain the disk, in order to prevent penetration into the middle cranial fossa. The term 'condylar reconstruction plate' reflects this more clearly than 'ramus prosthesis' which suggests permanent reconstruction. Long-term studies comparing the functional and aesthetic results of the various prostheses and condylar reconstruction plates are not available, which leaves the choice to personal experience.

History of radial head prosthesis in traumatology.

A review of the literature was performed to survey the history of the radial head prosthesis in traumatology. Radial head resection was the treatment of choice before Speed first reconstructed the radial head with a metal prosthesis. Over the years, the indication for the use of a radial head prosthesis changed from the prevention of heterotopic ossification to the prevention of proximal migration of the radius and instability of the elbow. Currently, the optimal indication for the use of radial head prostheses is a non-reconstructible radial head fracture with associated injuries that would leave the elbow, or forearm unstable if the radial head were resected.

Tissue Engineering of the TMJ disc: a review.

The potential impact of a tissue-engineered temporomandibular joint (TMJ) disc is immense. Currently, patients suffering from a severely dysfunctional TMJ have few options. Facing the general lack of safe, effective TMJ disc implants, many patients undergo discectomy, a procedure that removes the injured TMJ disc in hopes of reducing debilitating symptoms associated with severe TMJ disorders. This procedure may not be ideal as the TMJ is left without an important functional component. Tissue engineering is a promising approach for the creation of viable, effective implants. The first attempt to investigate TMJ disc cells on a biomaterial was conducted in 1991. The first TMJ tissue-engineered constructs to be tested biochemically and biomechanically were formed in 1994; however, in examining this study in retrospect, it is clear how little TMJ knowledge was available at that time. Within the last 10 to 15 years, multiple studies have investigated critical TMJ disc characteristics, and while this characterization is not complete, these data have created a solid foundation for tissue-engineering research. Thus, the last 5 years have yielded core studies investigating the principal elements of tissue engineering: scaffold, cell source, and biological/biomechanical stimuli. Although TMJ disc tissue engineering is still in its formative years, its future is quite promising. Key studies are now being conducted that will assist in the establishment of a solid TMJ disc tissue-engineering approach. As the challenges of tissue engineering are faced and met, the ultimate goal of creating a functional biological implant nears.