**3. Types of arthroplasty**

Although nowadays the term "arthroplasty" is strongly associated with the placement of a "prosthesis", there are other forms of arthroplasty that are still practiced and need to be recognized by the specialist in joint reconstructions. Many of them have only historical value for the hip and knee joints, where the development and success of metallic prostheses, which follow Charnley's "low friction" concept, have made it the gold standard

#### **Figure 1.**

*Types of arthroplasty: A) severely damaged joint, with significant reduction of joint space. The dashed line shows the original joint space width; B) excisional, which consists of simple resection of joint surfaces; C) Interpositional, when, in addition to the resection, some biological tissue or synthetic material is interposed between the joint surfaces; D) replacement, when a prosthesis is implanted to restore joint geometry.*

in the treatment of the vast majority of cases. But other joints, especially small joints and upper limbs can still benefit greatly from other forms of arthroplasty. **Figure 1** shows a schematic of the types of arthroplasty.

## **3.1 Excisional arthroplasties**

Also known as resection arthroplasty, it consists of removing part of the joint. The space that is left fills in with scar tissue over time. Nowadays, its use is indicated most often for correction of deformities in the toes (hallux rigid, hammer toe, mallet toe), for the treatment of rhizarthrosis in the trapezio metacarpal joint of the hand, and for some elbow problems. In hemophiliac patients, for example, hypertrophy of the radial head causes pain and limitation of pronation-supination. Radial head resection promotes good results in these patients.

It can also be used as a salvage procedure in difficult cases of the shoulder (Jones surgery) or hip (Girdlestone surgery). The functional result in the knee is very poor and should be avoided. It may be rarely indicated in cases of refractory infection of the prosthesis, in elderly patients, or in patients with no gait prognosis, in which comorbidities would make the performance of an arthrodesis risky.

The problem with resection arthroplasty is that it generates instability, often so severe as to render the limb virtually nonfunctional. Therefore, its purpose is to relieve pain in patients with low functional demand and without surgical conditions for other forms of arthroplasty.

#### **3.2 Interpositional arthroplasties**

Interpositional arthroplasty consists of the resection of damaged joint surfaces, with the interposition of biological tissue or synthetic materials. Although it has presented poor results in the past, mainly in load-bearing joints of the lower limbs, it currently plays a role in the treatment of some specific pathologies.

*Introductory Chapter: Past, Present, and Future of Joint Reconstructive Surgery DOI: http://dx.doi.org/10.5772/intechopen.109545*

In the small joints, an interposition arthroplasty is an option for surgical treatment of hallux rigidus, for elderly patients with low functional capacity. Also could be used to manage rizarthrosis, the so-called Eaton's arthroplasty with ligament interposition. Interpositional arthroplasty with temporalis fascia flap has been one of the most frequently performed procedures to treat temporomandibular joint ankylosis.

In large joints, it has been used frequently for elbow problems. It is considered a salvation option in young patients where conservative treatment has failed and total elbow arthroplasty is relatively contraindicated [3].

#### **3.3 Replacement arthroplasties**

The articular surface is partially or completely replaced by a prosthesis. The prosthesis protects the subchondral bone and restores joint geometry, returning normal tension to the ligaments and joint capsule. This is the most successful type of arthroplasty, the result of a long historical development, which led to the development of the prostheses currently in use. In joints such as the hip and knee, the superiority of replacement arthroplasty is indisputable, being considered the gold standard treatment in severe destruction. In the shoulder and ankle, promising results are beginning to be achieved.
