Midcarpal Hemiarthroplasty for Wrist Arthritis: Rationale and Early Results

Abstract

Painful wrist arthritis is a debilitating condition for which current treatment options are limited. The primary goal of treatment for the symptomatic, arthritic wrist is to achieve a pain-free, functional, and stable joint that is able to bear load. This is ideally achieved while preserving wrist motion. The causes of wrist arthritis are varied and include the sequelae of trauma, carpal instability, Keinböck disease, and inflammatory arthropathy. 1,2 The pattern and severity of articular involvement differ according to the etiology and guide the surgeon in recommending treatment. Ultimately, patients AbstractMidcarpal hemiarthroplasty is a novel motion-preserving treatment for radiocarpal arthritis and is an alternative to current procedures that provide pain relief at the expense of wrist biomechanics and natural motion. It is indicated primarily in active patients with a wellpreserved distal row and debilitating arthritic symptoms. By resurfacing the proximal carpal row, midcarpal arthroplasty relieves pain while preserving the midcarpal articulation and the anatomic center of wrist rotation. This technique has theoretical advantages when compared with current treatment options (i.e., arthrodesis and total wrist arthroplasty) since it provides coupled wrist motion, preserves radial length, is technically simple, and avoids the inherent risks of nonunion and distal component failure. The KinematX midcarpal hemiarthroplasty has an anatomic design and does not disrupt the integrity of the wrist ligaments. We have implanted this prosthesis in nine patients with promising early results. The indications for surgery were as follows: scapholunate advanced collapse wrist (three), posttraumatic osteoarthritis (three), inflammatory arthritis (two), and Keinböck disease (one). Prospective data has been collected and the results are preliminary given the infancy of the procedure. The mean follow-up was 30.9 weeks (range: 16 to 56 weeks). The mean Mayo wrist score increased from 31.9 preoperatively to 58.8 (p < 0.05) and the mean DASH score improved significantly from 47.8 preoperatively to 28.7 (p < 0.05). There was a trend toward increased motion but statistical significance was not reached. Two patients required manipulation for wrist stiffness. There was no evidence of prosthetic loosening or capitolunate narrowing. The procedure is simple (average surgical time was 49 minutes) and maintains coupled wrist motion through preservation of the midcarpal articulation. The preliminary data show that it appears safe but considerably longer follow-up is required before conclusions can be drawn as to its durability, reliability, and overall success. The level of evidence for this study is therapeutic level IV (case series).

Proximal‐distal shift of the center of rotation in a total wrist arthroplasty is more than twice of the healthy wrist

“…We demonstrated a consistent behavior of axis of rotation for the healthy wrists, while a more complicated pattern for the replaced wrist was observed, indicating the implants incapability in accomplishing these motions (Figure 11). This mismatch could potentially be due to the fact that most current implant designs are intended to replicate the radiocarpal joint, and not the midcarpal joint's kinematics 59 …”

Kienböck Disease: Recent Advances in the Basic Science, Assessment and Treatment

“…Hemiarthroplasty together with a PRC [84][85][86] has been described although the results are guarded at present (Fig. 8).…”

“…This situation could be managed with a hemiarthroplasty together with a PRC. [84][85][86] Alternatively, until the results of hemiarthroplasty have been established, a salvage procedure such as a total wrist fusion or arthroplasty could be performed.…”

Management of a Complex, Multioperated Intra-Articular Distal Radius Fracture

“…Wrist hemiarthroplasty is a novel approach reported in two series in the literature 3,4 with good intermediate results, which allows focal treatment of radiocarpal arthritis. The KinematX midcarpal hemiarthroplasty excises the radiocarpal joint by means of proximal row carpectomy, and the implant provides proximal carpal row replacement, thus preserving the midcarpal articulation, the anatomic center of rotation, and, consequently, the dart thrower's arc.…”

“…Poorer outcomes were experienced in patients with inflammatory arthritis. 3 Hemiarthroplasty is indicated in patients with a preserved distal carpal row and posttraumatic radiocarpal arthritis, scapholunate advanced collapse (SLAC) wrist, scaphoid nonunion advanced collapse (SNAC) wrist, or Kienböck disease. In patients with diseased midcarpal joints, hemiarthroplasty may not be the treatment option to provide the best results.…”