The proximal interphalangeal joint: arthritis and deformity

Proximal interphalangeal joint arthroplasty using self-locking type surface replacement implant for symptomatic osteoarthritis: Extended dorsal central splitting approach and intermediate-term outcome

BACKGROUND

This retrospective study introduced wide exposure and radical osteophytectomy by employing the extended dorsal central splitting approach (EDCSA) to mitigate complications associated with surface implant arthroplasty for osteoarthritis of the proximal interphalangeal (PIP) joint using a self-locking type of implant.

METHODS

In total, 171 fingers of 113 patients underwent cementless surface non-constrained PIP implantation using the EDCSA. The surgical approach involved larger implant placement, optional procedures, and complex collateral ligament repair following wide exposure and thorough shaving of the osteophytes and periarticular bone. Pre- and postoperative outcomes; range of motion; Quick Disabilities of the Arm, Shoulder, and Hand (Q-DASH) scores; subjective pain scores; radiographic findings; and patient satisfaction were assessed.

RESULTS

The active range of motion of the PIP joint improved from -18°/58° to -15°/84° (extension/flexion), and remaining stiffness (arc < 40°) was observed in 21 PIP joints (12%) at a mean follow-up of 4.8 years. Patients reported significantly reduced pain and improved Q-DASH scores, with 92% overall patient satisfaction. Radical osteophytectomy effectively prevented recurrence and heterotopic ossification. Complications in the operated fingers occurred in 24.0% of cases, with a reoperation rate of 8.8%, primarily due to soft tissue-related issues. No implant-related symptomatic complications were identified, except for 1 case of dislocation and 1 of mild implant loosening with infection.

CONCLUSION

Self-locking surface replacement implants offer stable fixation without failure in the intermediate term. The EDCSA demonstrated excellent results and advantages, leading to easy identification of each joint structure to facilitate radical osteophytectomy.

Utilization of Interphalangeal Joint Arthroplasty and Arthrodesis in the United States From 2010 to 2019

Background

Interphalangeal joint (IPJ) arthrodesis and arthroplasty are mainstay treatments for IPJ arthritis with conflicting evidence about the most efficacious choice. Our study describes case volume and incidence over the last decade (2010-2019).

Methods

The IBM MarketScan database was queried using Current Procedural Terminology codes for IPJ arthrodesis and arthroplasty from January 2010 to December 2019. Volume and incidence were estimated annually and according to sex, age, and US geographical region for 2010 and 2019.

Results

Annual volume and incidence of IPJ arthrodesis increased slightly from 2010 to 2019, though with overlapping confidence intervals for incidence. Arthrodesis tended to be higher in women versus men, especially with increasing age. When considering age, the most substantial increase in rates over increasing age was moving from the 40s to 50s age brackets. Across US regions, arthrodesis was higher in the northeast and midwest in 2010, though other rates rose and regions were similar by 2019. For IPJ arthroplasty, there was a 25%-30% decrease in case volume and incidence over the decade. Incidence was generally higher among women, with a similar jump in incidence from 40s to 50s among women, whereas men showed a more gradual rate increase with age. Regionally, arthroplasty was highest in the northeast and midwest in 2010, though it was similar across regions in 2019.

Conclusions

Although IPJ arthrodesis levels have stayed relatively stable, IPJ arthroplasty showed a general decline over the decade. Incidence of both were higher among women, and despite initial regional differences, rates became more similar by 2019.

The Hemiarthroplasty of the Proximal Interphalangeal Joint in Post-traumatic Degenerative Disease: A Case Report

Fractures of the proximal interphalangeal (PIP) joint with fragment displacement should be promptly repaired after injury, though this does not ensure the return of pre-injury finger function. This article presents the case of a 29-year-old patient who sustained an injury to the fourth finger of his right hand, resulting in an open fracture of the distal and shaft of the proximal phalanx involving the PIP joint and partial damage to the finger extensor mechanism. Immediately post injury, the fracture was realigned and stabilized with Kirschner wires (K-wires). Three years later, due to post-traumatic degenerative disease, the patient required further surgical intervention and was diagnosed with type III according to the modified Kellgren and Lawrence scale. The decision was made to perform a partial arthroplasty of the PIP joint. The implantation of the PIP prosthesis in a patient with post-traumatic degenerative disease can restore the correct range of flexion movement, realign the fourth digit, and eliminate pain. However, this treatment method may pose a risk of a slight limitation in the range of extension motion in the joint.

Comparative Finite Element (FE) Analysis of the Mechanical Behavior in an Innovative Nitinol Staple for Arthrodesis in Distal Interphalangeal Joint

Objective

Osteoarthritis (OA) is a source of significant limitations for individuals, health systems, and economies. The most common complications of OA are often associated with risk factors related to chronic diseases, cardiovascular disease, and depression. In this article, a new kind of staple is proposed, designed to provide better strength when subjected to bending and torque loads.

Methods

This innovative staple has been numerically tested and compared to a MEMOFIX staple by Smith + Nephew, in order to evaluate its mechanical behavior. The radius and ulna were fixed at the lower extremity, while the distal interphalangeal of the little finger was loaded with a bending load of 50 N and a torque moment of 500 N/mm2.

Results

For the bending load, a maximum value of stress of 120 MPa in the traditional staple, while 90 MPa are registered in the innovative one. The torsional load produces a value of 107 MPa in the traditional staple and 85 MPa in the innovative one.

Conclusion

Computational simulations showed the biomechanical performance of a new type of nitinol staple compared with a traditional one. This staple is designed with an elliptical shape in order to support different kinds of loads. Our results confirm an optimal mechanical behavior, compared to the traditional staple, in terms of the evaluated Equivalent Von Mises stress; also the contact force exerted by the innovative staple was increased.

Development of novel hybrid 3D-printed degradable artificial joints incorporating electrospun pharmaceutical- and growth factor-loaded nanofibers for small joint reconstruction

Small joint reconstruction remains challenging and can lead to prosthesis-related complications, mainly due to the suboptimal performance of the silicone materials used and adverse host reactions. In this study, we developed hybrid artificial joints using three-dimensional printing (3D printing) for polycaprolactone (PCL) and incorporated electrospun nanofibers loaded with drugs and biomolecules for small joint reconstruction. We evaluated the mechanical properties of the degradable joints and the drug discharge patterns of the nanofibers. Empirical data revealed that the 3D-printed PCL joints exhibited good mechanical and fatigue properties. The drug-eluting nanofibers sustainedly released teicoplanin, ceftazidime, and ketorolac in vitro for over 30, 19, and 30 days, respectively. Furthermore, the nanofibers released high levels of bone morphogenetic protein-2 and connective tissue growth factors for over 30 days. An in vivo animal test demonstrated that nanofiber-loaded joints released high concentrations of antibiotics and analgesics in a rabbit model for 28 days. The animals in the drug-loaded degradable joint group showed greater activity counts than those in the surgery-only group. The experimental data suggest that degradable joints with sustained release of drugs and biomolecules may be utilized in small joint arthroplasty.

Prosthesis Options for Proximal Interphalangeal Joint Arthroplasty in Osteoarthritis: A Systematic Review and Meta-Analysis

Background: Literature investigating the long-term outcomes of prosthesis options for proximal interphalangeal (PIP) joint arthroplasty is scarce, with most reports combining indications and underlying pathologies in analyses. In this study, we aim to compare silicone, pyrocarbon and metal prostheses in PIP joint arthroplasty for primary degenerative osteoarthritis (OA). Methods: A review of scientific literature published between 1990 and 2021 was conducted. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed. Relevant studies were screened and the appropriate data was extracted. An evaluation of clinical outcomes (range of motion [ROM] and pain), complications (reoperation) and survival rates for each prosthesis was performed. Results: Twelve studies were included for analysis with a total of 412 PIP joints. ROM was 66.6°, 55.8° and 46.4° for metal, silicone and pyrocarbon implants, respectively. Silicone implants had the best pain score on the visual analogue scale (1.2) followed by the pyrocarbon (2.6) and metal (3.9) groups. Complication rates were lowest in silicone implants (11.3%) compared to 18.5% in pyrocarbon and 22.4% in metal prostheses. Survival did not differ significantly amongst the three groups. Conclusions: Our findings suggest that for patients with primary degenerative OA, PIP joint arthroplasty using a silicone prosthesis can provide greater pain relief with lower complication rates compared to other implant options. Level of Evidence: Level III (Therapeutic).

Reported Outcomes and Outcome Measures in Proximal Interphalangeal Joint Arthroplasty: A Systematic Review

Purpose: There is a lack of scientific consensus on the best arthroplasty implant option for proximal interphalangeal joint (PIPJ) arthritis, due to diversity in outcome reporting and measurement methods. The development of a standardized core outcome set (COS) and standard outcome measures could mitigate this issue. This study catalogs the reported outcomes and outcome measures found in PIPJ arthroplasty studies, which can be used in the first step of developing a COS. Methods: A database search of MEDLINE, EMBASE, and Web of Science (January 1, 2010, to March 10, 2021) was performed to retrieve studies that reported outcomes of the 3 most common primary PIPJ arthroplasty implants: silicone, pyrocarbon, and metal-polyethylene. The primary objectives of this study include reported outcomes and outcome measures. Secondary objectives include clinimetric properties of outcome measures, study design, and implant types. Results: Fifty articles met inclusion criteria. Of the included studies, 41 (82%) were case series, 8 (16%) were cohort studies, and 1 (2%) was a randomized control trial. Thirty-three unique outcomes were identified. Fifteen (46%) outcomes were clinician-reported and 26 (79%) were patient-reported. Eighteen unique outcome measures were identified. Of the outcome measures, 15 (83%) were patient-reported, 1 (6%) was clinician-reported, and 2 (11%) were reported by both patients and clinicians. Conclusions: Substantial heterogeneity was found in reported outcomes and outcome measures across studies evaluating PIPJ arthroplasty, impeding knowledge translation. The development of a COS for PIPJ arthroplasty is necessary to help compare and pool data across studies, and advance scientific knowledge.

Korrektur von Fingerdeformitäten

Deformitäten der Langfinger sind neben „Rheumaknoten“ die auffälligsten Veränderungen einer bestehenden Rheumatoiden Arthritis. Die Therapie beinhaltet neben der medikamentösen Einstellung der Patienten konservative Maßnahmen, in deren Mittelpunkt die Ergotherapie steht. Neben konservativen und interventionellen Versorgungen sollte die Synovialektomie zu einem frühen Zeitpunkt erwogen werden, um die Gelenke langfristig zu schützen. Bei fortgeschrittenen Deformitäten müssen periartikuläre Strukturen in der Operation adressiert werden, um Funktionsdefizite so gering wie möglich zu halten. Gleichzeitig ist auf Grund der Dynamik der Grunderkrankung immer mit einer Progredienz und erneuten Operationen zu rechnen. Eine einzelne für ein Gelenk spezifische operative Maßnahme existiert nicht, vielmehr gilt es die verschiedenen Möglichkeiten und erforderliche Alternativen in der Planung zu berücksichtigen, um diese in der Operation entsprechend dem Ziel durchführen zu können.

Arthrodesis of the Proximal Interphalangeal Joint of the Finger—A Biomechanical Study of Primary Stability

Background: Osteoarthritis of the proximal interphalangeal (PIP) joint of the finger often leads to global hand-function detriment. Different techniques for the arthrodesis of the proximal interphalangeal joint have been described that all lead to union in a reasonable percentage of patients and period of time. This biomechanical study aims to analyze and compare the primary stability of different techniques of arthrodesis to render postoperative immobilization unnecessary. Methods: Arthrodeses of 40° of composite cylinders were tested with different techniques in four-point bending for stability in extension as well as flexion. Results: In extension, the compression screw and the compression wires showed the highest stability—whereas in flexion, plate fusion was superior. Tension band, cerclage or compression screw fusion showed the best compromise in flexion/extension stability. Conclusions: Fusion techniques that apply compression to the fusion show superior stability. Cerclage, tension band and compression screws might be able to provide enough stability to withstand the forces exerted during unencumbered activities of daily living. Arthrodesis with plates should be limited to patients with special indications and require immobilization during consolidation.

Shifting the paradigm: ankylosis arthroplasty for the proximal interphalangeal joint with a novel collateral ligament reconstruction

Silicone arthroplasty for proximal interphalangeal joint ankylosis is rarely performed, partly due to the potential for lateral joint instability. We present our experience performing proximal interphalangeal joint arthroplasty for joint ankylosis, using a novel reinforcement/reconstruction technique for the proper collateral ligament. Cases were prospectively followed-up (median 13.5 months, range 9-24) and collected data included range of motion, intraoperative collateral ligament status and postoperative clinical joint stability; a seven-item Likert scale (1-5) patient-reported outcomes questionnaire was also completed. Twenty-one ankylosed proximal interphalangeal joints were treated with silicone arthroplasty, and 42 collateral ligament reinforcements undertaken in 12 patients. There was improvement in range of motion from 0° in all joints to a mean of 73° (SD 12.3); lateral joint stability was achieved in 40 out of 42 of collateral ligaments. High median patient satisfaction scores (5/5) suggest that silicone arthroplasty with collateral ligament reinforcement/reconstruction should be considered as a treatment option in selected patients with proximal interphalangeal joint ankylosis.Level of evidence: IV.

Proximal interphalangeal joint prosthetic arthroplasty

Surgical treatment of the painful proximal interphalangeal (PIP) joint has evolved considerably over the past century. If arthrodesis has long been the gold standard and remains so for some, prosthesis would meet patient demand: mobility and indolence. Faced with a demanding patient, the surgeon must decide the indication, the type of prosthesis, the approach, the post-operative follow-up, etc. The history of the development of PIP prostheses demonstrates the complexity of the treatment of the destroyed PIP: appearance of prostheses, evolution and sometimes disappearance from the market for commercial reasons or related to complications. The main objective of this conference is to identify the main indications for prosthetic arthroplasties and to describe the various prostheses available on the market.

Radiological positioning of a proximal interphalangeal joint resurfacing implant: Reliability and functional outcomes correlation

OBJECTIVES

The aims of this study were to define radiological measurements for quantifying the position of a surface replacing implant (CapFlex-PIP) in the proximal interphalangeal (PIP) joint, to test the reliability of these measurements, and to explore whether implant position influences patient-reported and clinical outcomes one year after surgery.

MATERIAL AND METHODS

We developed 7 radiographic measurements to quantify the position of the proximal and distal implant components. Two independent surgeons analyzed the 1-year postoperative radiographs of 63 fingers documented in our registry. Inter-rater reliability of these measurements was calculated with the intraclass correlation coefficient (ICC). Correlations between the radiographic measurements and PIP range of motion (ROM), the brief Michigan Hand Outcomes Questionnaire (MHQ), and pain were determined using Spearman's correlation coefficient. Radiographic measurements of patients with the worst and best postoperative ROM were compared using the Mann-Whitney-U test.

RESULTS

Inter-rater reliability was only good for 1 measurement (ICC = 0.89), but poor to moderate for the other measurements (ICC ranging from 0.34 to 0.69). These measurements neither correlated with ROM, brief MHQ nor pain based on correlation coefficients ranging from 0.00 to 0.31. There were no relevant differences in the radiographic measurements between patients with the worst and best ROM.

CONCLUSION

The position of the CapFlex-PIP implant could not be reliably quantified on plain radiographs. The lack of correlations between implant position and postoperative outcomes can be attributed either to the unreliable measurements or the actual lack of influence of the implant position on pain and function.

Proximal Interphalangeal Joint Arthrodesis Techniques: A Systematic Review

Proximal interphalangeal joint (PIPJ) arthrodesis is a salvage option in the management of end-stage PIPJ arthropathy. Numerous techniques have been described, including screws, Kirschner wires, tension band wiring, intramedullary devices, and plate fixation. There remains no consensus as to the optimum method, and no recent summary of the literature exists. A literature search was conducted using the MEDLINE, EMBASE, and PubMed databases. English-language articles reporting PIPJ arthrodesis outcomes were included and presented in a systematic review. Pearson χ2 and 2-sample proportion tests were used to compare fusion time, nonunion rate, and complication rate between arthrodesis techniques. The mean fusion time ranged from 5.1 to 12.9 weeks. There were no statistically significant differences in fusion time between arthrodesis techniques. Nonunion rates ranged from 0.0% to 33.3%. Screw arthrodesis demonstrated a lower nonunion rate than wire fusion (3.0% and 8.5% respectively; P = .01). Complication rates ranged from 0.0% to 22.1%. Aside from nonunions, there were no statistically significant differences in complication rates between arthrodesis techniques. The available PIPJ arthrodesis techniques have similar fusion time, nonunion rate, and complication rate outcomes. The existing data have significant limitations, and further research would be beneficial to elucidate any differences between techniques.

Patient-Reported Outcomes 1 Year After Proximal Interphalangeal Joint Arthroplasty for Osteoarthritis

PURPOSE

Implant survival, range of motion, and complications of proximal interphalangeal joint arthroplasty have been reported often, but patient-reported outcomes are less frequently described. This study evaluated patients' experiences during the first year after proximal interphalangeal joint arthroplasty, measured with the Michigan Hand Outcomes Questionnaire (MHQ). The primary focus was the reduction of patient-reported pain after proximal interphalangeal joint implant placement and the percentage of patients who considered this reduction clinically relevant, indicated by the minimal clinically important difference (MCID).

METHODS

Data were collected prospectively; 98 patients completed the MHQ before and at 3 and 12 months after surgery. Our primary outcome was the change in the pain score. An increase of 24 points or more was considered a clinically important difference. Secondary outcomes included changes in MHQ total and subscale scores and MCIDs, range of motion (ROM), patient satisfaction with the outcome of the surgery, and complications.

RESULTS

The pain score improved significantly, from 42 (95% confidence interval, 38-46) at baseline to 65 (95% confidence interval, 60-69) at 12 months after surgery. The MCID was reached by 50% (n = 49) of patients. The ROM did not improve, reoperations occurred in 13% (n = 13) of patients, and swan neck deformities only occurred among surface replacement implants.

CONCLUSIONS

Although most patients undergoing arthroplasty for osteoarthritis experienced significantly less pain after surgery, the pain reduction was considered clinically relevant in only 50% (n = 49) of patients. Patients with high MHQ pain scores before surgery are at risk for postoperative pain reduction that will not be clinically relevant. Likewise, the other subscales of the MHQ improved after surgery, but reached a clinically relevant improvement in only 46% (n = 45) to 63% (n = 62) of patients. This knowledge can be used during preoperative consultation to improve shared decision making.

TYPE OF STUDY/LEVEL OF EVIDENCE

Prognostic IV.

The biomechanics of osteoarthritis in the hand: Implications and prospects for hand therapy

BACKGROUND

The unique anatomy of the human hand makes it possible to carefully manipulate tools, powerfully grasp objects, and even throw items with precision. These apparent contradictory functions of the hand, high mobility for manual dexterity vs high stability during forceful grasping, imply that daily activities impose a high strain on a relatively instable joint. This makes the hand susceptible to joint disorders such as osteoarthritis. Both systemic (eg, genetics, hormones) and mechanical factors (eg, joint loading) are important in the development of osteoarthritis, but the precise pathomechanism remains largely unknown. This paper focuses on the biomechanical factors in the disease process and how hand therapists can use this knowledge to improve treatment and research.

CONCLUSION

Multiple factors are involved in the onset and development of osteoarthritis in the hand. Comprehension of the biomechanics helps clinicians establish best practices for orthotics intervention, exercise, and joint protection programs even in de absence of clear evidence-based guidelines. The effect and reach of hand therapy for OA patients can be expanded substantially when intervention parameters are optimized and barriers to early referrals, access reimbursement, and adherence are addressed. Close and early collaboration between hand therapists and primary care, women's health, rheumatology, and hand surgery providers upon diagnosis, and with hand surgeons pre and postoperatively, combined with advances in the supporting science and strategies to enhance adherence, appear to be a promising way forward.

An outcomes study of proximal interphalangeal joint silicone implant arthroplasty using the volar approach

BACKGROUND

Arthroplasty is performed at the proximal interphalangeal joint (PIP) for the management of disabling osteoarthritis. This prospective cohort study evaluated outcomes of the silicone implant for the PIP joint using the volar approach. We hypothesize that the volar approach without extensor mechanism disruption will provide improved motion, while maintaining joint extension.

METHODS

Consecutive candidates for PIP silicone implant arthroplasty using the volar approach were evaluated. The Michigan Hand Outcomes Questionnaire (MHQ) and functional measurements including grip/pinch strength and arc of motion (AOM) were administered preoperatively, and at 6 weeks, 3, 6, and 12 months postoperatively. Means and ranges were calculated for continuous variables and proportions for discrete variables. Mean differences were assessed using paired t-tests and effect size.

RESULTS

Twenty-eight patients (35 joints) were included in the study. Eighteen patients (24 joints) were followed to 1 year postoperatively with an entire cohort average of 10-month follow up. Nineteen patients were Caucasian females and mean age of the cohort was 64 years. Our hypothesis was supported by the results showing a mean gain in PIP AOM of 7° and mean 5° extension lag improvement at one year. The mean postoperative AOM was 53° with a 10° average extension lag. The median MHQ pain score improved: 70 (60-80) to 28 (5-45) as did each of the MHQ domains. Median grip strength was unchanged: pre-op 14.3 (10.2-22.7) kg to 16.8 (13.8-19.4) kg at 1 year.

CONCLUSIONS

The volar approach to PIP arthroplasty is technically challenging but facilitates early aggressive rehabilitation. This is critical in providing improved flexion, especially in the ulnar digits without worsening extension lag.

Outcomes of Multiple Digit Proximal Interphalangeal Joint Swanson Arthroplasty Done at a Single Operation

Background: Proximal interphalangeal joint (PIPJ) arthroplasty using a Swanson implant is commonly used for the treatment of PIPJ arthritis despite newer implants being available. Many patients develop arthritis in more than one digit and some tend to have multiple digits operated on in their lifetime. There is paucity of literature on the outcomes of multiple PIPJ arthroplasty in one sitting. The aim of this study is to determine the outcomes of PIPJ arthroplasty using a Swanson implant done for multiple digits at one sitting. Methods: We retrospectively reviewed the outcomes of multiple Swanson PIPJ arthroplasty during a single operation from 2008 to 2018 in 13 patients (43 arthroplasties). We compared pre- and post-operative results of flexion/extension arcs, grip and pinch strength and questionnaires subsequently compared QuickDASH (Disabilities of Arm, Shoulder and Hand), Patient Evaluation Measure (PEM) and Visual Analogue Score (VAS) scores. Data were analysed with a Mann-Whitney U test. Results: Patients on average attended 5.6 hand therapy sessions over 5.1 months post-operatively. Average flexion/extension arc improved from 31.9° pre-operatively to 37.2° post-operatively. Average grip strength increased from 7.2 kg to 10.2 kg. The QuickDASH, PEM and VAS scores improved in keeping with the reported literature. There were no implant failures. Conclusion: We demonstrate similar outcomes for multi-digit Swanson PIPJ arthroplasty compared to the literature for single digit Swanson PIPJ arthroplasty. We conclude that multi-digit arthroplasty in a single operation is safe and effective. Level of Evidence: Level IV (Therapeutic).

Arthroplasty in the hand: what works and what doesn't?

This review describes the different possibilities for arthroplasties at the proximal interphalangeal joint, thumb carpometacarpal joint, distal radioulnar joint, metacarpophalangeal joint and the wrist. For each joint, the indication for arthroplasty is explained, the surgical technique with the suitable implant is described and a brief summary of the outcomes reported in the literature is given.

Proximal interphalangeal joint arthroplasty with the Tactys® prosthesis: Clinical and radiological outcomes at a mean 3.1 years' follow-up

Preliminary results with the Tactys® modular gliding prosthesis for proximal interphalangeal joint (PIPJ) replacement were encouraging, with notable improvement in clinical and functional scores at 1 and 2 years' follow-up. However, a recent study found a trend for deterioration over time. We wanted to check this by analyzing medium-term outcomes. Sixty-four arthroplasties were performed in 48 patients in single facility between January 2015 and January 2020. Clinical, functional, and radiographic outcomes were analyzed at short- and medium-term follow-up for 15 of these arthroplasties. Mean follow-up of the 48 patients was 3.1 years. Pain significantly decreased on the numeric rating scale (p < 0.01) and the functional QuickDASH score improved from 67.3 to 55.9 (p < 0.01). Grip and pinch strengths were lower in the operated than in the contralateral hand (p = 0.04 and p = 0.6, respectively). PIPJ active range of motion (ROM) in flexion/extension improved from 44° to 49.4° (p = 0.17). 70% of the 48 patients were satisfied. Fifteen arthroplasties were analyzed at 17 and 61 months' follow-up. Pain relief continued. ROM decreased from 57° to 46° (p < 0.05) and the functional QuickDASH score deteriorated from 25.8 to 54.7 (p < 0.01). Both grip and pinch strength increased, with a significant difference in pinch (p = 0.003). The main complication was swan-neck deformity (46%), with a mean 11 months' onset. Our results confirmed the deterioration trend observed over time in the functional results of the Tactys® prosthesis despite, good patient satisfaction. LEVEL OF EVIDENCE: 4.

[Joint Arthroplasty with a silastic Spacer in open defect Injuries of a Finger Joint during primary Surgery]

Silastic spacer replacement for the treatment of destroyed finger joints due to degenerative, post-traumatic or rheumatoid osteoarthritis has been well established for years. In acute severely traumatized hands silastic spacer replacement is seldomly performed We report five consecutive patients in whom a defect injury of a finger joint was replaced by a silicone implant without complications during primary care. We reviewed all our patients with a follow up of at least 8 months. In all patients healing was uneventful, with no infections and a functional range of motion. No patient complained about instability. With the right patient selection, joint replacement with silastic spacers is a valuable alternative to arthrodesis in acute destroyed finger joints.

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.

Complications after surface replacing and silicone PIP arthroplasty: an analysis of 703 implants

INTRODUCTION

The aim was to analyse complications after surface replacing and silicone proximal interphalangeal (PIP) joint arthroplasty.

MATERIALS AND METHODS

All complications, reoperations (subsequent intervention without implant modification) and revisions (subsequent surgery with implant modification or removal) were extracted out of our registry for two cohorts: (1) Patients who received a surface replacing arthroplasty at the PIP joint using the CapFlex-PIP prosthesis and (2) patients who received a PIP silicone implant. Furthermore, radiographs were evaluated for deviations from the longitudinal finger axis.

RESULTS

In our registry, 279 surface replacing implants and 424 silicone implants have been documented. The overall complication rate was 20% for surface replacements and 11% for silicone arthroplasties (p ≤ 0.01) with soft tissue-related events being the most prevalent in both groups. Reoperations were significantly more frequent after surface replacement (5.4%) than silicone arthroplasty (0.5%; p ≤ 0.001), while the revision rates did not differ significantly (4.4% and 3.3%, respectively; p = 0.542). Postoperative axis deviations were significantly less frequent in the surface replacement group (19% versus 58% for silicone arthroplasty; p ≤ 0.001).

CONCLUSION

We recommend using a surface replacing implant in fingers with preoperative axis deviations and correctable anatomical situation, bearing in mind the higher risk of a second surgery. However, treatment outcomes also need to be considered before choosing one implant over another.

A New Proximal Dorsal Approach for DIP Arthroplasty

Degenerative changes of the distal interphalangeal (DIP) joints can be painful, disabling, and disfiguring. Swanson spacers can be used for DIP arthroplasty. The standard approach for Swanson spacer implantation at the DIP joint involves transecting the extensor tendon close to its insertion, which necessitates a 6-week period of postoperative immobilization. Another DIP approach involves sparing the extensor tendons, as already published. Both techniques lead to a similar range of motion of the replaced DIP joints. We present a novel approach for DIP joint arthroplasty with division of the extensor tendon in zone 2 with only 2 weeks of postoperative immobilization. Optimizing the motion-preserving operative approaches is of value to our high-demand patients. Postoperative results do not differ from the postoperative range of motion published in the literature for both tendon-sparing and standard approaches. But our approach is technically easy and requires a significantly shorter time of immobilization.