Early outcomes of arthroplasty of the first carpometacarpal joint using pyrocarbon spherical implants

Abstract

The first carpometacarpal joint (CMC) is the most common hand joint to develop osteoarthritis. A survey found that many hand surgeons have revisited implant arthroplasty because it preserves critical structures. However, there is currently no implant with an ideal design and material composition. The present study was the first to use and evaluate early outcomes of pyrocarbon spherical implants for arthroplasty of the first CMC in patients with Eaton-Littler stage II and III osteoarthritis. A single surgeon performed 24 arthroplasties (23 patients [20 women, three men] with a mean age of 56 years [range 46 to 75 years]) of the first CMC (nine right hands and 15 left hands) using pyrocarbon spherical implants from May 2010 to April 2013. All patients failed conservative management. At a mean (± SD) of 18.5±11.16 months postoperatively (range 4.3 to 38.9 months), the mean Kapandji score was 8.8 of 10 (range 7 to 10), the average pre- and postoperative values on the visual pain scale were 8.96±0.64 of 10 (range 8 to 10) and 1.13±1.22 of 10 (range 0 to 4), respectively. All patients were either very satisfied (score = 5) or satisfied (score = 4) with the procedure, with a mean satisfaction score of 4.76±0.44 of 5.00 (range 4 to 5). The mean postoperative Disabilities of the Arm, Shoulder and Hand (DASH) score was 11.79±14.29 (range 0 to 49.17). The most recent radiographic evaluations confirmed that all implants were stable with no erosion of nearby cancellous bone. There were no implant subluxations, dislocations or revisions. Early outcomes show promising results and support continued use of this implant for arthroplasty. However, longer-term follow-up will be needed to confirm these results.

Keywords: Arthroplasty; Carpometacarpal osteoarthritis; Pyrocarbon; Spherical implant.

Figure 1)

A pyrocarbon spherical implant for arthroplasty of the first carpometacarpal joint (Integra LifeSciences Corporation, USA)

Figure 2)

Surgical technique of arthroplasty of the first carpometacarpal joint (CMC) using pyrocarbon spherical implants. A Marking the incision over the first CMC joint of the left hand. B From the radial styloid process, a longitudinal incision was made over the extensor pollicis brevis and the abductor pollicis longus tendons, terminating 1.5 cm distal to the base of the metacarpal bone. C The deep branch of radial artery was identified, freed and protected with a vessel loop. D The capsular periosteal flaps were elevated to expose the joint. E Following the resection of the distal surface of the trapezium and the base of the first metacarpal bone with a sagittal saw, the implant sizer was placed flat on the surface of the trapezium. F A round bur was used on the two resected surfaces to produce a cup in the centre. G A Broach (raspatory) was used to polish the surface of the cups. H and I The pyrocarbon spherical implant was inserted into position using an implant retriever. J Closure of the joint capsule using 2-0 undyed TiCron (Covidien, USA) sutures. K Closure of the skin using 4-0 Monocryl (Ethicon, USA) sutures

Figure 3)

Plain radiograph of the right hand following arthroplasty of the first carpometacarpal joint using a spherical pyrocarbon implant

Figure 4)

A 62-year-old woman with a Kapandji score of 10 of 10 for the left thumb (A) and right thumb (B), 29.6 and 17.3 months postoperatively, respectively