Silicone and Pyrocarbon Artificial Finger Joints

Artificial finger joint design has been developed through different stages through the past. PIP (proximal interphalangeal) and MCP (metacarpophalangeal) artificial finger joints have come to replace the amputation and arthrodesis options; although, these artificial joints are still facing challenges related to reactive tissues, reduced range of motion, and flexion and extension deficits. Swanson silicone artificial finger joints are still common due to the physician’s preferability of silicone with the dorsal approach during operation. Nevertheless, other artificial finger joints such as the pyrocarbon implant arthroplasty have also drawn the interests of practitioners. Artificial finger joint has been classified under three major categories which are constrained, unconstrained, and linked design. There are also challenges such as concerns of infections and articular cartilage necrosis associated with attempted retention of vascularity. In addition, one of the main challenges facing the silicone artificial finger joints is the fracture occurring at the distal stem with the hinge. The aim of this paper is to review the different artificial finger joints in one paper as there are few old review papers about them. Further studies need to be done to develop the design and materials of the pyrocarbon and silicone implants to increase the range of motion associated with them and the fatigue life of the silicone implants.

Prosthetic Replacement of the Scaphoid Proximal Pole: Should It Be the Future?

Background Scaphoid proximal pole fractures with avascular necrosis represent a complex surgical problem. Many reconstruction techniques are based on osteosynthesis with a vascularized or nonvascularized bone graft. These procedures do not allow early mobilization and therefore sometimes lead to unsatisfying functional results. In some cases, it is possible to perform a scaphoid hemiarthroplasty using a pyrocarbon implant (adaptive proximal scaphoid implant [APSI]) in place of the necrotic proximal pole, allowing an early mobilization and delaying palliative treatments such as 4-corner arthrodesis or proximal row carpectomy. Methods In this study, we reviewed all patients who had undergone a scaphoid hemiarthroplasty using APSI in our institutions from 1999 to 2017; the F.U. was performed through radiographic, clinical, and subjective (Disabilities of the Arm, Shoulder, and Hand) analysis. Results The performances of scaphoid proximal pole implants are encouraging; radiographic, clinical, and subjective outcomes were good, and the functional recovery proved to be fast and reliable over time. Conclusions This study reports our experience in the use of APSI implants, which proved to be a good alternative to traditional techniques for treating avascular necrosis of the proximal pole, still allowing further surgical steps in case of clinical worsening over time (wrist osteoarthritis). These patients are usually young and present high functional demands. Our experience is promising, but we believe that further evaluation over time will be needed.

Resurfacing capitate pyrocarbon implant after proximal row carpectomy: A literature review

Up to a decade ago, to treat patients with chronic wrist pain due to advanced stages of arthritis, surgeons had four main solutions: partial or total wrist arthrodesis, total wrist prosthesis and proximal row carpectomy (PRC). Since 2010, a new technique has been described in literature using the Resurfacing Capitate Pyrocarbon Implant (RCPI), combined to PRC. The aim of this article is to review the literature and determine the indications, outcomes and complications associated with RCPI. An electronic literature research was carried out and pertinent articles were selected. Surgical technique, results and complications described in those articles are presented. From this review of the literature, authors conclude that Resurfacing Capitate Pyrocarbon Implant can be considered as a good alternative to arthrodesis and total wrist arthroplasty, at any ages, when proximal row carpectomy alone would not be indicated.

Treatment of Pisotriquetral Arthritis by Pyrocarbon Interposition Arthroplasty

Purpose Pisiformectomy is the baseline treatment for pisotriquetral arthritis when medical treatment fails to address the problem. This operation may lead to loss of mobility and strength in the wrist. This study reports the short-term outcomes of a new technique for treating pisotriquetral arthritis using a pisotriquetral interposition arthroplasty with a pyrocarbon implant. Patients and Methods We performed a clinical and radiographic study on a series of eight patients who received this treatment at a mean follow-up of 2.8 years. We also studied the mobility of the implant and did assessed articular instability using dynamic radiology and fluoroscopy. Results We observed one proximal dislocation of the implant in one hand which was reoperated to reposition the implant and strengthen the capsule. All patients were satisfied or very satisfied with their operation and had an average functional recovery period of 1.6 months. At the last follow-up, the Mayo Wrist Score (MWS), Quick Disability of Arm Shoulder and Hand (QDASH), and Patient-Rated Wrist Evaluation (PRWE) scores were 89, 18, and 20, respectively. Postoperatively, there was a 22% improvement in the grip strength of the wrists as well as improved mobility, mainly as regards the radioulnar deviation (47% improvement) and the Visual Analogue Scale (VAS) pain scores decreased from 8 preoperatively to 2 at the latest follow-up. The functional radiologic and fluoroscopic study reported good adaptive mobility of the implant in all the patients, without any indication of pisotriquetral joint instability. Conclusion The short-term results of pisotriquetral arthroplasty using the Pyrocardan implant are encouraging. This new surgical solution appears to be a valid alternative to pisiformectomy or pisotriquetral arthrodesis. Long-term studies are required to confirm these preliminary findings.