Use of grommets for flexible implant resection arthroplasty of the metacarpophalangeal joint.

In 1987, after 11 years of research, press fit titanium circumferential grommets were introduced for arthroplasty of the metacarpophalangeal joint to protect the flexible hinge implant midsection from sharp bony edges and shearing forces that can initiate implant abrasions and tears leading to implant fracture and formation of silicone wear particles. The effectiveness of the titanium circumferential grommets was assessed by comparing the results of 170 metacarpophalangeal joint implant (high performance) arthroplasties performed with (139 joints) and without (31 joints) grommets in 38 patients presenting an average 5.8 years followup. Both groups obtained pain relief, functional motion, stability, and correction of deformity. There was no evidence of particulate synovitis or infection. There were four implant fractures (12.9%) in the nongrommet group, and one (0.7%), because of implant rotation, in the grommet group. Although favorable bone remodeling was observed in both groups, the grommet group showed greater bone preservation at the metaphyseal and midshaft levels and increased intramedullary bone production around the implant stems. The results depend on appropriate surgical staging, meticulous operative and postoperative techniques, severity and progression of disease, and implant durability. The circumferential grommets safely and effectively protect the implant to bone interface to further the durability of implant arthroplasty of the metacarpophalangeal joint.

Experience of total wrist arthroplasty with silastic implants plus grommets.

The experience with radiocarpal joint reconstruction in rheumatoid arthritis using silastic implants and titanium grommets is reported. Forty-one implants were placed in 36 patients from 1986 to 1992, with a followup of 32 implants in 29 patients ranging from 2.5 years to 8 years. After a brief review of the crucial points of the procedure, including indications and surgical technique, the results were examined using a protocol derived from the one proposed in 1988 for an international multicenter study. The procedure, when correct indications are selected and correct surgical steps are performed, allows predictable results with a satisfying recovery of wrist function. Preservation of wrist function through the years seems enhanced by titanium grommets.

The Norway elbow replacement. Design, technique and results after nine years.

The Norway elbow prosthesis is a non-constrained cemented total replacement. It depends on intact collateral ligaments for stability, and allows a full range of movement. The system includes several sizes of components, all freely interchangeable, and semi-constraint can be provided by a locking ring if damaged collateral ligaments make dislocation possible. The prosthesis has been used in more than 350 elbows in Norway and the detailed results for 118 elbows studied prospectively since 1987 are reported. It is inserted through a posterolateral triceps-splitting incision with minimal muscle disruption and bone resection, preserving the collateral ligaments. The results as regards pain relief and range of movement were comparable with those of other elbow prostheses, but there were fewer serious complications. At a mean follow-up of 4.3 years, the failure rate was 3.4%.

Braided polypropylene augmentation device in reconstructive surgery of the anterior cruciate ligament: long-term clinical performance of 594 patients and short-term arthroscopic results, failure analysis by scanning electron microscopy, and synovial histomorphology.

Long-term clinical results and short-term arthroscopic and microscopic findings from two augmented reconstruction procedures for the ruptured anterior cruciate ligament are reported. The braided polypropylene ligament augmentation device (Kennedy model) was used with temporary double-end fixation in 279 patients to augment the attachment of the anterior cruciate ligament after acute proximal rupture and in 315 patients to augment a bone-tendon-bone autograft, mainly after chronic instability. Check arthroscopy was performed and the metal fixation hardware was removed after a mean of 11 months. Of the 569 patients evaluated, 101 partial or total breakages of the ligament augmentation device were found. Together with nine breakages detected late in the follow-up period, 110 (19.3%) failures were found. Most of these failures were accompanied by effusion that was immediately alleviated when the failed device was removed. No generalized synovitis was visible. Scanning electron microscopic analysis of 24 retrieved failed ligament augmentation devices showed fatigue to be the principal failure mode, together with local abrasion at the fracture. Synovial biopsies were taken during arthroscopy in 84 patients with and without ligament augmentation device-failure who had given informed consent, and histological evaluation revealed that in 21 patients, chronic but no acute synovial inflammation was found, and wear particles could be identified in foreign body cells in 17. Statistically, the presence of chronic synovitis was predicted neither by wear particles and foreign body cells nor by abrasion or fatigue failure of the ligament augmentation device. Irrespective of the failures, for which ligament augmentation device removal is recommended, in the final Orthopaedische Arbeitsgemeinschaft Knie evaluation (after a mean of 6.2 years), excellent and good clinical results were found in 83.6% of all 594 patients.

Optimisation of ultraclean air. The role of instrument preparation.

The use of ultraclean air (UCA) in operating theatres reduces the infection rate after joint replacement but some cases of infection still occur. We investigated one possible source of contamination, namely the setting up of instruments in a conventional plenum-ventilated preparation room. We measured bacterial fallout using agar settle plates and compared instruments set up in the preparation room with those set up in the UCA theatre, assessed the effect of covering instruments after preparation and compared fallout during their preparation with total fallout throughout the operation. Our findings showed that covering the instruments reduced total bacterial fallout fourfold by reducing the exposure time, particularly during periods of increased activity and bacterial dispersal. Preparation in the UCA theatre and subsequent covering of the instruments reduced total fallout 28-fold. All measurable bacterial fallout occurred during the setting up and not during surgery.

High implant fracture incidence with Sutter silicone metacarpophalangeal joint arthroplasty.

We performed a retrospective review of Sutter silicone metacarpophalangeal (MP) joint arthroplasties in 34 patients (42 hands, 168 implants) with rheumatoid arthritis. Patients were evaluated at an average of 27 months (minimum follow-up period, 12 months). Twenty percent of the implants were shown to be definitely fractured on final follow-up examination, and 45% followed for more than 3 years were definitely fractured. At the final follow-up examination, the average ulnar drift in intact implants was 11 degrees and in the fractured implants, 23 degrees. However, there was no correlation between implant fracture and patient satisfaction. Eighty percent of patients said they would undergo the procedure again. Because of a significantly higher implant fracture incidence at a relatively shorter follow-up period than that of most studies of silicone MP implants of the Swanson design, we have abandoned the use of the Sutter implant.

Isolation and quantitation of debris particles around failed silicone orthopedic implants.

Silicone elastomer implants have a relatively low rate of complications, but inflammatory reactions to debris have been reported. To characterize the size and number of debris particles, we isolated and quantified the debris particles present in the periarticular tissues of 10 patients with failed silicone wrist, elbow, or finger implants. Five rheumatoid synovia without implants were used for negative controls. The number of particles ranged from 0.99 to 24.8 x 10(9) per gram (dry weight) of tissue, and nearly all particles were silicone, as determined by x-ray spectroscopy. The implantation duration ranged from 3.2 to 10.6 years, and for the five wrist implants, the number of particles correlated with duration in vivo. The particles were small (mode particle diameter was 0.59 +/- 0.057 micron). These results suggest that billions of particles, most of which are smaller than 1 micron, are present adjacent to failed silicone implants, and may be associated with inflammation and bone resorption.

The immune response to implant materials in humans.

The etiology of aseptic loosening of prosthetic joint replacement components is unclear. Implant materials have been considered biologically inert, but recently studies indicate that inflammatory reactions directed against the implanted materials may contribute to aseptic loosening. Data suggesting a progression from a simple inflammatory reaction to complex immune responses against the biomaterials are reviewed. The cellular responses to particles of polymethylmethacrylate, ultrahigh molecular weight polyethylene, and alloys of cobalt-chromium and titanium were assayed in vitro to determine cell proliferation in patients with underlying diagnoses of osteoarthrosis, rheumatoid arthritis, and avascular necrosis who had joint replacement. Control populations were provided by patients with similar diagnoses who were preoperative surgical candidates. The underlying diagnoses did not seem to influence responses to particle stimulation. Elevated responses to both acrylic and cobalt-chromium were observed in patients with aseptically loosened prostheses. These findings suggest that the development of a cellular response to particulate debris may be significant in the pathogenesis of aseptic loosening.

Cylindrical cemented ankle arthroplasty: a prospective series with long-term follow-up.

From 1981 to 1985 28 ankle arthroplasties were performed using a congruent and cylindrical ankle design. The talus component was an anatomically shaped cap to cover the talus dome and the facets. The tibial component was congruent toward the talus and had two parallel bars on the back for fixation into the distal tibia. The diagnosis was osteoarthritis in 15 cases and rheumatoid arthritis in 11 cases (two bilateral cases). There were seven failures, giving a cumulative estimated survival rate of 70% for the prosthesis at 12 years.

Silastic single-stem implants in the treatment of hallux rigidus.

Forty cases of hallux rigidus treated by Silastic hemiarthroplasty over an average period of 110 months have been reviewed here. As many as 36% (14 feet) of the patients were unhappy with the results of their operation. Six implants had to be removed because of increasing pain and fragmentation of the prosthesis. These patients improved after the prosthesis was removed. It is concluded that Silastic hemiarthroplasty does not give an acceptable level of good results when compared with published reports of other forms of treatment. The probable causes of the high dissatisfaction rate are discussed.

Pioneers of shoulder replacement: Themistocles Gluck and Jules Emile Péan.

Dr. Jules Emile Péan is widely credited with having performed the first total shoulder replacement March 11, 1893, at the Hôpital International in Paris. However, in his original report Péan refers to the work of Themistocles Gluck as being the inspiration for his shoulder prosthesis, a fact understated if not completely overlooked during the last hundred years. This article therefore attempts to reappraise the relative contributions of these two pioneering surgeons to shoulder arthroplasty.

Painful basal joint arthritis of the thumb. Part II: Treatment.

Treatment of arthritis of the basal joint has evolved from resection of the trapezium, to joint replacement, to reconstruction of the lost anterior oblique ligament. These, along with other operative options, will be discussed in detail. The advantages and disadvantages of each will be presented. The complications of earlier methods of management have allowed refinements in surgical intervention. It is these improvements that have allowed the clinician to more reliably treat the arthritic thumb carpometacarpal joint.

An intramedullary aligned bone cutting jig for elbow replacement.

One of the main post operative complications of total elbow replacement has been dislocation and fracture of the olecranon. This has been associated with rotational malalignment of the bone cuts of the proximal ulna caused by the current free hand cutting method. This paper presents an intramedullary aligned bone cutting jig which gives rotational location on the ulna for the bone cuts, without notching the olecranon.

The radiology of total shoulder replacement.

The indications for total shoulder replacement and the radiologic evaluation prior to the operation are discussed in depth in this article. Different approaches to clinical problems are also discussed and illustrated, as are normal findings. This is followed by a discussion of the complications of shoulder reconstruction, including infection, fractures, and heterotopic bone formation. A review of the results is also given followed by a brief mention of a number of other orthopedic shoulder devices and plates.

New instruments, bone liners, and tray for finger joint arthroplasty.

Titanium circumferential grommets have been developed for finger joint arthroplasty that fit on the base of the silicone implant stems to protect the flexible hinge from tearing and fracture. To facilitate grommet insertion, new intramedullary bone rasps have been devised with a reverse cutting tooth pattern, an extended shaft for an improved view of the surgical field, and a redesigned cutting head to allow for grommet insertion. Surgical accessibility and ease of recognition have been facilitated by the development of color-coded sizers. All of the instruments necessary for finger joint surgery are available in a molded tray that has also been redesigned with a transparent lid and clearly labeled compartments for accurate determination of instruments and implant sizers.

An overview of first metatarsophalangeal joint implant arthroplasty.

The metatarsophalangeal joint of the great toe often requires an arthroplasty to correct joint disease and pain. Today, joint replacement systems are combinations of components manufactured to optimize biological ingrowth, mechanical interlock, press fit, and cementing. Three different types of arthroplasties are available to foot surgeons: the double stem hinged silicone implant, the two-component joint mimicking implant, and a hemi-implant available for the phalanx. No comprehensive studies on very large populations have been conducted to accurately evaluate the beneficial long-term effects of these implants. This review article describes the development of the toe arthroplasty, details the commercially available implants, and addresses the advantages and adverse effects of each implant.

Finite element stress analysis of the wrist joint without and with an endoprosthesis.

The finite element analysis method was used to obtain the lateral deformation profile and values of the von Mises stress in the cortical and cancellous regions of the various bones in models of a selected space in the coronal plane of a human wrist joint, without and with a prosthesis. The prosthesis was the metacarpal component of the Trispherical design of the total wrist joint arthroplasty. The models included all the bones, the associated network of ligaments, and the intervening soft muscle tissue. Each type of model was completely constrained along its entire proximal surface and subjected to either a static point force (in the axial compressive or anteroposterior tensile direction) acting at the center of the distal tip of the third metacarpal cortical bone. For the models containing the prosthesis, a parametric study was conducted involving the method of anchorage of the prosthesis to the contiguous bones and the material of fabrication of the prosthesis. It was found that: (1) the axial force produces lower stresses in the bones compared with the anteroposterior one; (2) no clear-cut case can be advanced, from the stress viewpoint, for press-fitting the prosthesis to the contiguous bones rather than using bone cement for such anchorage; and (3) any alloy with modulus of elasticity in the 79 to 196 GPa range and Poisson's ratio of about 0.3 may be used to fabricate the prosthesis. The approximations used and the associated limitations of the work are fully discussed, as are the design implications and clinical significance of the results.

The total wrist joint arthroplasty: biomechanical considerations and research directions.

A review of the state-of-the-art knowledge base on the biomechanics of the wrist joint, with emphasis on total wrist joint arthroplasty, is presented. The reasons for the reported high rate of aseptic loosening of the metacarpal component of such an implant are unknown at this time. It is suggested that detailed stress analyses of models of the joint, without and with the aforementioned implant, will yield results that will increase understanding of this problem and improve implant design, resulting in enhanced clinical performance of these replacements. For this purpose, it is recommended that the finite element analysis method be used.