CHAPTER 51 Elbow Arthroplasty: Historical Perspective and Emerging Concepts

INTRODUCTION

The first “modern” total elbow arthroplasty using bone cement was performed by Dee in 1972. However, in the late 1940s and early 1950s, documentation of replacement of the elbow by means of hemiarthroplasties as well as custom distal humerus or proximal ulna articular bearing materials exists. All of these efforts suffered from poor fixation and lack of understanding of the joint kinematics. In 1952, Venable ⁴⁸ and in 1965 Barr and Eaton³ designed endoprostheses for the distal humerus, usually for reconstructing traumatic deficiencies (Fig. 51-1). There were also efforts made to create a custom ulnohumeral joint when the elbow was unstable and fusion was the only alternative.^11,^28,²⁹ These early elbow designs exhibited various articular and fixation concepts (Fig. 51-2). However, without bone cement, these prostheses usually became loose and unstable (see Fig. 51-1).

FIGURE 51-1 A, Vitallium replacement prosthesis for distal humerus. Instability (B) and loosening (C) were common problems.

FIGURE 51-2 A, Linked devices were employed for devastating bone loss. B to D, Various articular and design concepts were employed.

In the 1970s, the concept of resurfacing emerged. These designs were intended for more limited pathology. Mayo was actively involved with early efforts to design both hemi and articulated devices (Fig. 51-3).²³ The so-called “saddle” was a true resurfacing of the olecranon designed at Mayo in the later 1960s, and was successful in some instances³⁸ (Fig. 51-4). Street and Stevens⁴⁷ are credited with the first use of a convex trochlea and capitellum replacement of the distal humerus (Fig. 51-5). The goal of these implants was a hemiarthroplasty replacement that required less bone resection and, it was hoped, preservation of the collateral ligaments. Materials such as nylon, acrylic, stainless steel, and even vulcanized rubber were used in these early prostheses. Although some were successful in relieving pain, most had limited motion, were often unstable without adequate ligamentous support and loosened over time. A few long-term successes were reported; but in general, joint function was limited and the clinical experience consisted of only a few patients.

FIGURE 51-3 A, Replacement prosthesis for the proximal ulna (designed by EW Johnson and AP Schlein). The original proximal ulna replacement lasted 13 years before requiring revision to a custom Mayo-Coonrad total elbow arthroplasty. B and C, Custom total elbow revision replacement of the elbow.

FIGURE 51-4 A, A vitallium “saddle” designed by Bickel and Peterson to resurface the proximal ulna. B, Fifteen-year follow-up of a patient with post-traumatic arthritis treated with the vitallium “saddle.” There was mild pain and motion from 80 to 135 degrees.

(From Peterson, L. F. A., and Jones, J. M.: Surgery of the rheumatoid elbow. Orthop. Clin. North Am. 2:667, 1971.)

FIGURE 51-5 A, Distal humerus resurfacing prosthesis designed by Street and Stevens. B, Three-year follow-up of a Stevens-Street prosthesis. Note the new cortical bone growth around the prosthesis.

(From Street, D. M., and Stevens, P. A.: A humeral replacement prosthesis for the elbow: Results in ten elbows. J. Bone Joint Surg. 56A:1147, 1974.)

The era of total elbow joint prosthetic replacement followed the limited success with these custom-designed and resurfacing hemiarthroplasty. We consider the “modern” era of prosthetic replacement to have begun in the early 1970s with the design of Dee, followed by a number of hinged elbow arthroplasties ^7,^9,^19,^21,^39,⁴⁶ (Fig. 51-6). This and other prostheses almost uniformly provided pain relief and a reasonable range of elbow motion (20 degrees of extension, to 110 to 120 degrees of flexion).

FIGURE 51-6 A, The Dee prosthesis was a rigid, metal-on-metal implant that required complete resection of the humerus for implementation. B, Unfortunately, these deficiencies of concept could not be overcome by cement fixation.

The important features of the Dee prosthesis is that it was the first implant to use cement fixation. However, the lack of understanding the complex anatomy and biomechanics resulted in a particularly high early failure rate that progressed to virtually 100% failure with time. The disadvantage of rigid fixation and predictable failure was recognized worldwide. Some devices were modified to address the initial design flaws such as the GSB from Zurich (Fig. 51-7). Roland Pritchard was one of the first in this country to recognize the value of a “loose hinge” and a polyethylene bushing (Fig. 51-8). Others sought the desirability of stability and flexibility with a “snap-fit” articulation. The design by Volz also incorporated a radial head to better distribute the forces crossing the joint⁴⁹ (see Fig. 51-8). Unfortunately these design concepts suffered from deficiencies of technique, soft tissue balance and bushing wear. A less constrained articulation was also attained by a snap fit with some systems (see Fig. 51-8). Finally, Coonrad recognized the problem with a medial/lateral articulation and a collared polyethylene bushing was introduced in 1970 (Fig. 51-9).

FIGURE 51-7 A, The original GSB was a rigid metal-on-metal articulation. B, Severe osteolysis resulted from this design. C, The current version allows rotation and translation through polyethylene bushing.

FIGURE 51-8 A, The Pritchard-Walker articulated generation II design provided an 8-degree varus/valgus laxity of the articulation. B and C, The Arizona design was a snap fit device that also incorporated a radiohumeral element with radial head replacement and capittelar resurfacing.

FIGURE 51-9 Original Coonrad prosthesis consisted of a polyethylene bushing at the humerus and a polyethylene insert at the ulna.

Unfortunately, complication rates proved very high from loosening, component fracture, and infection leading to a rate of reoperation of 22% to 30%. Hence, the whole concept was reassessed.

Loosening at the bone-cement interfaces was the predicated price paid for rigid-constraint prostheses.^7,^10,¹⁷ Early recognition of this problem prompted interest in and the development of more prostheses that were not mechanically coupled. These so-called resurfacing or uncoupled designs^14,^16,^25,⁴⁶ (Fig. 51-10) are best termed unlinked implants and prompted various efforts to restore the anatomic contour. The earliest designs also tried, unsuccessfully, to avoid the use of a stemmed implant. These implants intended to lessen stresses on the bone-cement interface, allowing the soft tissue capsule and ligaments to transmit forces and decrease the risk of mechanical loosening. Over the years, these theoretical advantages have proved to be effective, however, only to the extent that the unlinked device is also less constrained at the articulation. We now know that it is the articular constraint, not the linkage per se, that influences loosening.

FIGURE 51-10 A, “Anatomic” or “resurfacing” total elbow prosthesis are best termed “unlinked.” Wadsworth’s experience demonstrated the need for a stem. B, The capitellocondylar prosthesis was more anatomic with a humeral design to allow articulation with a radial head component. C, The Souter-Strathclyde metal humeral and polyethylene ulnar component was the most constrained of all unlinked devices. D, Pritchard unconstrained ulnohumeral, with radial head humeral articulation. Technical and design problems rendered this unreliable. E and F, The Questor designed by Sorbie is one of the most sound implants. G, The Kudo Elbow System is a cobalt-chrome alloy humeral component articulated with a polyethylene bearing titanium alloy ulnar component. The current humeral stem achieves fixation without cement.

Our clinical experience with the more modern designs at the Mayo Clinic began in 1971 with the original Coonrad hinged prosthesis. This was composed of humeral and ulna components separated by a high-density polyethylene bushing (see Fig. 51-9).³⁵ Our experience with this design was flawed by poor stem fixation (Fig. 51-11). With a more sophisticated understanding of biomechanics and after studying our own and the clinical experience of others, a three-piece, semiconstrained, flanged device was designed in 1978 (Fig. 51-12). Morrey inserted two of these devices, and the second one dislocated. The design was abandoned, but the value of the flange concept was believed to be sound and it was incorporated into the Coonrad implant.