Complications Related to Metal-on-Metal Articulation in Trapeziometacarpal Joint Total Joint Arthroplasty

Long-term results of 292 CarpoFit®-joint replacements for trapeziometacarpal osteoarthritis: a prospective cohort study with a 10-year follow-up

We report a prospective consecutive series of CarpoFit® (Implantcast, Buxtehude, Germany) trapeziometacarpal prostheses used between 2006 and 2014 for 292 patients with stage I-III trapeziometacarpal arthritis who remained symptomatic after conservative treatment. Patients were assessed at 3 months, 6 months and 1 year postoperatively for thumb movement, pinch strength and by validated patient-derived outcome scores and radiographs. Follow-up at 5 and 10 years was by outcome scores alone. Complications and revisions were recorded. Of the patients, 91% were either satisfied or very satisfied with their treatment at 10 years. Pain relief and functional outcomes were significantly improved within 3 months. Results were sustained during the entire observation period. The implant survival was 95% after 10 years. Prosthetic arthroplasty is a reliable treatment option for trapeziometacarpal osteoarthritis and the CarpoFit® prosthesis has excellent long-term results for patient satisfaction, functional scores and implant survivorship.Level of evidence: III.

Metal hypersensitivity in trapeziometacarpal arthroplasty: A systematic pattern of progression

Metal hypersensitivity is a rare and often underestimated complication, as shown by the small number of published studies, particularly concerning the upper limbs and the hand. However, the increase in the annual number of trapeziometacarpal arthroplasties underlines the importance of better understanding of this problem. We performed a study based on data from the revision of trapeziometacarpal prostheses to assess the incidence of this complication and to define a sequence of radiological changes to detect metal hypersensitivity. This single-center retrospective study included 37 patients operated on between January 2014 and November 2023 for revision of trapeziometacarpal prosthesis. Ten (27%) had no clearly identified cause of failure. For these 10 patients, we analyzed clinical data and postoperative X-rays. In the 11 revision arthroplasties, 2 patients had no symptoms or radiographic signs suggestive of allergy. Six patients had a-posteriori diagnosis established by allergy testing, which also identified 2 additional patients, for a total of 8 patients (21% of the initial cohort). In these cases, there was systematic metaphyseal osteolysis of the first metacarpal between 15 days and 1 month after implantation. Clinically, most patients had an asymptomatic period of 2 weeks to 1 month before onset of symptoms and osteolysis, often accompanied by local inflammation. This study found a reproducible pattern of progression, characterized by the appearance of radiographic signs of osteolysis in the first month, followed by clinical deterioration. Although this course is strongly suggestive of a metal hypersensitivity, it is crucial not to exclude the possibility of an infectious cause, which should always be considered.

A review of wear debris in thumb base joint implants

AIM

Polymers and metals, such as polyethylene (PE) and cobalt chrome (CoCr), are common materials used in thumb-based joint implants, also known as CMC (Carpometacarpal) arthroplasty. The purpose of this review was to investigate the reported failure modes related to wear debris from these type of materials in CMC implants. The impact of wear debris on clinical outcomes of CMC implants was also examined. Potential adverse wear conditions and inflammatory particle characteristics were also considered.

METHOD

A literature search was performed using PRISMA guidelines and 55 studies were reviewed including 49 cohort studies and 6 case studies. Of the 55 studies, 38/55 (69%) focused on metal-on-polyethylene devices, followed by metal-on-metal (35%), and metal-on-bone (4%).

RESULTS

The summarized data was used to determine the frequency of failure modes potentially related to wear debris from metals and/or polymers. The most commonly reported incidents potentially relating to debris were implant loosening (7.1%), osteolysis (1.2%) and metallosis (0.6%). Interestingly the reported mechanisms behind osteolysis and loosening greatly varied. Inflammatory reactions, while rare, were generally attributed to metallic debris from metal-on-metal devices. Mechanisms of adverse wear conditions included implant malpositioning, over-tensioning, high loading for active patients, third-body debris, and polyethylene wear-through. No specific examination of debris particle characterization was found, pointing to a gap in the literature.

CONCLUSION

This review underscores the types of failure modes associated with wear debris in CMC implants. It was found that failure rates and adverse wear conditions of CMC implants of any design are low and the exact relationship between wear debris and implant incidences, such as osteolysis and loosening remains uncertain. The authors note that further research and specific characterization is required to understand the relationship between debris and implant failure.

Pyrocardan Implant Arthroplasty for Carpometacarpal Osteoarthritis of the Thumb: A Comparative Study with a Historical Control Group

Background  New and improved surgical techniques are warranted to treat osteoarthritis of the thumb carpometacarpal joint (CMC-1). The Pyrocardan implant yields striking results but only few series exist, making the evidence scarce. Purpose  The aim of this study was to conduct a prospective series using the Pyrocardan implant. Methods  We compared the outcomes to a matched historical control group of patients operated on with ligament reconstruction and tendon interposition. The hypothesis was that the Pyrocardan implant would yield better patient-reported outcomes as well as the procedure would be safe and effective in relieving symptoms of CMC-1 osteoarthritis. In total, 30 patients were included in the prospective series. These 30 patients were compared, in a 1:3 design, to a matched historical group. Results  Results were promising with visual analogue scale scores of 0.7 (rest) and 2.1 (function), key-pinch score of 5.1 kg, and shortened Disability of the Arm, Shoulder, and Hand score of 14.3 after 1 year when using the Pyrocardan implant. The revision rate was 10%. We found no evidence of subsidence of the thumb. We found no differences in patient-reported outcomes between the two groups. Conclusions  In conclusion, the Pyrocardan implant is a viable option in the treatment of CMC-1 osteoarthritis but with a significant revision rate. When comparing the Pyrocardan implant to a historical control group, we failed to find any differences in patient-reported outcomes. Level of Evidence  IV - case series.

Arthroplasty in thumb trapeziometacarpal (CMC joint) osteoarthritis: An alternative to excision arthroplasty

Trapeziectomy for base of thumb arthritis is well established, but base of thumb arthroplasty offers potential advantages. The review covers the development of arthroplasty for the thumb from interposition arthroplasty to total joint replacement. It discusses contemporary prosthesis designs and results, including trapezial component geometry, bearing surfaces, and dual mobility.

Joint replacement for trapeziometacarpal osteoarthritis: implants and outcomes

For thumb carpometacarpal osteoarthritis, trapeziectomy provides generally good results with reduction of pain and restoration of thumb mobility, but shortening of the thumb may at least in theory lead to reduction in grip and pinch strength. Furthermore, instability of the base of the first metacarpal and contact with the scaphoid may occur regardless of the several described techniques with ligament reconstruction and tendon interposition. Thus, for years alternatives to trapeziectomy have been explored and reported with disputable success. Often the road from idea to implantation in patients seems to have been short, and high complication rates and failure of new implant designs have been fairly common. This has led to the general impression that the implants do not provide sufficient benefits compared with simple trapeziectomy. More recent uncemented total joint replacement designs have shown rapid rehabilitation, reduction of pain, restoration of grip strength and movement, and much improved long-term implant survival. These factors may make total joint replacement a realistic alternative to trapeziectomy. Still, patient selection has to be improved, as the benefits may be small in the low activity elderly patient.

Periosteal pseudotumor in complex total knee arthroplasty resembling a neoplastic process

This case report describes in detail an erosive distal diaphyseal pseudotumor that occurred 6 years after a complex endoprosthetic hinge total knee arthroplasty (TKA). A female patient had conversion of a knee fusion to an endoprosthetic hinge TKA at the age of 62. At her scheduled 6-year follow-up, she presented with mild distal thigh pain and radiographs showing a 6-7 cm erosive lytic diaphyseal lesion that looked very suspicious for a neoplastic process. An en bloc resection of the distal femur and femoral endoprosthesis was performed. Histologic review showed the mass to be a pseudotumor with the wear debris emanating from within the femoral canal due to distal stem loosening. We deduce that mechanized stem abrasion created microscopic titanium alloy particles that escaped via a small diaphyseal crack and stimulated an inflammatory response resulting in a periosteal erosive pseudotumor. The main lesson of this report is that, in the face of a joint replacement surgery of the knee, pseudotumor formation is a more likely diagnosis than a neoplastic process when encountering an expanding bony mass. Thus, a biopsy prior to en bloc resection, would be our recommended course of action any time a suspicious mass is encountered close to a TKA.

Chrome nitride coating reduces wear of small, spherical CrCoMo metal-on-metal articulations in a joint simulator

Metal-on-metal articulations have fallen out of favour in larger joint replacements, but are still used in smaller joints. Coating the articulation has been suggested as one way of reducing wear. We compared a standard 6 mm CrCoMo articulation designed for the carpometacarpal joint of the thumb with a chromium nitride-coated version after 512,000 cycles in a joint simulator. A total of 6 articulations in each group were tested with a unidirectional load of 5 kg in Ringer's solution. We found a statistically significant reduction in weight loss, amount of metallic wear produced and volumetric wear for the chromium nitride-coated articulation. Our findings support the use of chromium nitride coating in order to minimize the amount of metallic wear produced.