Aims. To examine the mid-term outcome and cost utility of the BioPro metallic hemiarthroplasty for the treatment of hallux rigidius. Patients and Methods. We reviewed 97 consecutive BioPro metallic hemiarthroplasties performed in 80 patients for end-stage hallux rigidus, with a minimum follow-up of five years. There were 19 men and 61 women; their mean age was 55 years (22 to 74). No patient was lost to follow-up. Results. A total of 12 patients (15 first metatarso-phalangeal joints (MTPJs)) required a revision; one for infection, two for osteolysis and 12 for pain. The all cause rate of survival at five years was 85.6% (95% confidence interval (CI) 83.5 to 87.9). Younger age was a significant predictor of revision (odds ratio 1.09, 95% CI 1.02 to 1.17, p = 0.014) on excluding infection and adjusting for confounding variables (Cox regression). Significant improvements were demonstrated at five years in the Manchester Oxford Foot Questionnaire (13.9, 95% CI 10.5 to 17.2) and in the physical component of the Short Form-12 score (6.5, 95% CI 4.1 to 8.9). The overall rate of satisfaction was 75%. The cost per quality adjusted life year at five years, accounting for a 14% rate of revision was between £4431 and £6361 depending on the complexity and morbidity of the patient. Conclusion. The BioPro hemiarthroplasty offers good short to mid-term functional outcome and is a cost effective intervention. The relatively high revision rate is associated with younger age and perhaps the use of this implant should be limited to older patients. Cite this article: Bone Joint J 2016;98-B:945–51

Our aim was to compare polylevolactic acid screws with titanium screws when used for fixation of the distal tibiofibular syndesmosis at mid-term follow-up. A total of 168 patients, with a mean age of 38.5 years (18 to 72) who were randomly allocated to receive either polylevolactic acid (n = 86) or metallic (n = 82) screws were included. The Baird scoring system was used to assess the overall satisfaction and functional recovery post-operatively. The demographic details and characteristics of the injury were similar in the two groups. The mean follow-up was 55.8 months (48 to 66). The Baird scores were similar in the two groups at the final follow-up. Patients in the polylevolactic acid group had a greater mean dorsiflexion (p = 0.011) and plantar-flexion of the injured ankles (p < 0.001). In the same group, 18 patients had a mild and eight patients had a moderate foreign body reaction. In the metallic groups eight had mild and none had a moderate foreign body reaction (p <  0.001). In total, three patients in the polylevolactic acid group and none in the metallic group had heterotopic ossification (p = 0.246). We conclude that both screws provide adequate fixation and functional recovery, but polylevolactic acid screws are associated with a higher incidence of foreign body reactions. Cite this article: Bone Joint J 2014;96-B:548–54

Reports of differing failure rates of total hip prostheses made of various metals prompted us to measure the size of metallic and polyethylene particulate debris around failed cemented arthroplasties. We used an isolation method, in which metallic debris was extracted from the tissues, and a non-isolation method of routine preparation for light and electron microscopy. Specimens were taken from 30 cases in which the femoral component was of titanium alloy (10), cobalt-chrome alloy (10), or stainless steel (10). The mean size of metallic particles with the isolation method was 0.8 to 1.0 microns by 1.5 to 1.8 microns. The non-isolation method gave a significantly smaller mean size of 0.3 to 0.4 microns by 0.6 to 0.7 microns. For each technique the particle sizes of the three metals were similar. The mean size of polyethylene particles was 2 to 4 microns by 8 to 13 microns. They were larger in tissue retrieved from failed titanium-alloy implants than from cobalt-chrome and stainless-steel implants. Our results suggest that factors other than the size of the metal particles, such as the constituents of the alloy, and the amount and speed of generation of debris, may be more important in the failure of hip replacements

We assessed the short- to mid-term survival of metallic press-fit radial head prostheses in patients with radial head fractures and acute traumatic instability of the elbow. The medical records of 42 patients (16 males, 26 females) with a mean age of 56 years (23 to 85) with acute unstable elbow injuries, including a fracture of the radial head requiring metallic replacement of the radial head, were reviewed retrospectively. Survival of the prosthesis was assessed from the radiographs of 37 patients after a mean follow-up of 50 months (12 to 107). The functional results of 31 patients were assessed using range-of-movement, Mayo elbow performance score (MEPS), Disabilities of the Arm, Shoulder and Hand (DASH) score and the RAND 36-item health survey. At the most recent follow-up 25 prostheses were still well fixed, nine had been removed because of loosening, and three remained implanted but were loose. The mean time from implantation to loosening was 11 months (2 to 24). Radiolucent lines that developed around the prosthesis before removal were mild in three patients, moderate in one and severe in five. Range of movement parameters and mass grip strength were significantly lower in the affected elbow than in the unaffected side. The mean MEPS score was 86 (40 to 100) and the mean DASH score was 23 (0 to 81). According to RAND-36 scores, patients had more pain and lower physical function scores than normal population values. Loosening of press-fit radial head prostheses is common, occurs early, often leads to severe osteolysis of the proximal radius, and commonly requires removal of the prosthesis

We measured the tension in the interosseous membrane in six cadaveric forearms using an in vitro forearm testing system with the native radial head, after excision of the radial head and after metallic radial head replacement. The tension almost doubled after excision of the radial head during simulated rotation of the forearm (p = 0.007). There was no significant difference in tension in the interosseous membrane between the native and radial head replacement states (p = 0.09). Maximal tension occurred in neutral rotation with both the native and the replaced radial head, but in pronation if the radial head was excised. Under an increasing axial load and with the forearm in a fixed position, the rate of increase in tension in the interosseous membrane was greater when the radial head was excised than for the native radial head or replacement states (p = 0.02). As there was no difference in tension between the native and radial head replacement states, a radial head replacement should provide a normal healing environment for the interosseous membrane after injury or following its reconstruction. Load sharing between the radius and ulna becomes normal after radial head Replacement. As excision of the radial head significantly increased the tension in the interosseous membrane it may potentially lead to its attritional failure over time. Cite this article: Bone Joint J 2013;95-B:1383–7

A technique of subtalar arthrodesis by means of metallic internal stabilisation and autogenous cancellous bone grafting is described. Of forty-eight feet with mobile pes planus treated by this method forty-five gained union after an average of seven and a half weeks in a below-knee weight-bearing plaster, and forty-three had satisfactory correction of the deformity

Aims

This study aimed to determine if macrophages can attach and directly affect the oxide layers of 316L stainless steel, titanium alloy (Ti6Al4V), and cobalt-chromium-molybdenum alloy (CoCrMo) by releasing components of these alloys.

1. After almost seventeen years the three metal prostheses remain in approximately the original position in which they were inserted.

2. All three patients are ambulatory and two of them pleased with the result.

3. The youngest patient, now fifty-six, has a solid ankylosis of the hip and leads an active life free of pain.

4. In view of the attritional changes which have been seen to occur as a result of the reaction of bone to metal, it is suggested that resection replacement operations should be reserved for the primary treatment of certain fractures in the elderly and in those patients who are expected to be mostly inactive for the rest of their life. As a rough guide, it is considered that the operation should not be carried out under the age of seventy.

1. Experiments using radio-isotope techniques show that whenever an orthopaedic appliance is inserted into the body tiny fragments of the instruments used to handle it become detached and welded on to the surface of the buried metal.

2. There is evidence that these particles of non-passive tool-metal may cause a small but continuing dissolution of the stainless metal to which they are attached, and that this dissolution, although too small to be detected as visible corrosion, may produce an adverse tissue reaction.

3. In samples of human tissue taken from sites adjacent to buried metal the greatest level of tissue reaction and the highest concentration of iron were found near those parts of the appliances that had been handled with the tools and received the greatest amount of transferred metal.

4. Spectroscopic analyses of similar samples confirmed that the concentration of metal in the tissues surrounding a buried appliance correlates closely with the distribution on its surface of transferred tool metal. Particularly high concentrations of chromium, nickel, and cobalt were found near regions where the transfer had been heavy. The dissolution was not limited to the non-passive foreign metal; the stainless appliance was also dissolved in those regions.

5. The influence of the manner of handling the tools on the amount and distribution of transfer has been studied, and suggestions are made whereby the transfer might be reduced.

1. Radiological and histological observations of the tissue changes resulting from the implantation of various metals in the long bones of dogs are recorded.

2. Of the metals employed, tantalum, Vitallium, alloys "C" and "S" and F.M.B. steel were inert; silver and mild steel were reactive; F.S.T. steel occupied an intermediate position.

3. A correlation has been demonstrated between the anodic back E.M.F., the weight loss due to corrosion and the histological changes produced.

Aims. A significant reduction in wear at five and ten years was previously reported when comparing Durasul highly cross-linked polyethylene with nitrogen-sterilized Sulene polyethylene in total hip arthroplasty (THA). We investigated whether the improvement observed at the earlier follow-up continued, resulting in decreased osteolysis and revision surgery rates over the second decade. Methods. Between January 1999 and December 2001, 90 patients underwent surgery using the same acetabular and femoral components with a 28 mm metallic femoral head and either a Durasul or Sulene liner. A total of 66 hips of this prospective randomized study were available for a minimum follow-up of 20 years. The linear femoral head penetration rate was measured at six weeks, one year, and annually thereafter, using the Dorr method on digitized radiographs with a software package. Results. In the Durasul group, no patients underwent revision due to loosening or showed radiological evidence of osteolysis. In the Sulene group, four patients (four hips) were revised due to femoral component loosening. The 20-year cumulative failure incidence in the presence of the competing event of death for revision surgery was 4.5% (95% confidence interval (CI) 0.8 to 13.6) in the Durasul group, and 8.9% (95% CI 2.8 to 19.5) in the Sulene group. The mean wear one year after surgery was 0.09 mm (SD 0.007) in the Durasul group and 0.24 (SD 0.015) in the Sulene group (p < 0.001). From one to 20 years after surgery, the mean total penetration was 0.32 mm (SD 0.045) in the Durasul group and 1.07 mm (SD 0.13) in the Sulene group (p < 0.001). Mean femoral head penetration at 20 years was approximately 70.0% less in the Durasul group than the Sulene group. Conclusion. The significant reduction in femoral head penetration obtained with the Durasul compared with Sulene in uncemented THA resulted in lower osteolysis and revision rates after 20 years. Cite this article: Bone Joint J 2022;104-B(9):1032–1038

Aims. Modular dual mobility (MDM) acetabular components are often used with the aim of reducing the risk of dislocation in revision total hip arthroplasty (THA). There is, however, little information in the literature about its use in this context. The aim of this study, therefore, was to evaluate the outcomes in a cohort of patients in whom MDM components were used at revision THA, with a mean follow-up of more than five years. Methods. Using the database of a single academic centre, 126 revision THAs in 117 patients using a single design of an MDM acetabular component were retrospectively reviewed. A total of 94 revision THAs in 88 patients with a mean follow-up of 5.5 years were included in the study. Survivorship was analyzed with the endpoints of dislocation, reoperation for dislocation, acetabular revision for aseptic loosening, and acetabular revision for any reason. The secondary endpoints were surgical complications and the radiological outcome. Results. The overall rate of dislocation was 11%, with a six-year survival of 91%. Reoperation for dislocation was performed in seven patients (7%), with a six-year survival of 94%. The dislocations were early (at a mean of 33 days) in six patients, and late (at a mean of 4.3 years) in four patients. There were three intraprosthetic dissociations. An outer head diameter of ≥ 48 mm was associated with a lower risk of dislocation (p = 0.013). Lumbrosacral fusion was associated with increased dislocation (p = 0.004). Four revision THAs (4%) were further revised for aseptic acetabular loosening, and severe bone loss (Paprosky III) at the time of the initial revision was significantly associated with further revision for aseptic acetabular loosening (p = 0.008). Fourteen acetabular components (15%) were re-revised for infection, and a pre-revision diagnosis of reimplantation after periprosthetic joint infection (PJI) was associated with subsequent PJI (p < 0.001). Two THAs had visible metallic changes on the backside of the cobalt chromium liner. Conclusion. When using this MDM component in revision THA, at a mean follow-up of 5.5 years, there was a higher rate of dislocation (11%) than previously reported. The size of the outer bearing was related to the risk of dislocation. There was a low rate of aseptic acetabular loosening. Longer follow-up of this MDM component and evaluation of other designs are warranted. Cite this article: Bone Joint J 2021;103-B(7 Supple B):66–72

Periprosthetic joint infection (PJI) is one of the most dreaded complications after arthroplasty surgery; thus numerous approaches have been undertaken to equip metal surfaces with antibacterial properties. Due to its antimicrobial effects, silver is a promising coating for metallic surfaces, and several types of silver-coated arthroplasty implants are in clinical use today. However, silver can also exert toxic effects on eukaryotic cells both in the immediate vicinity of the coated implants and systemically. In most clinically-used implants, silver coatings are applied on bulk components that are not in direct contact with bone, such as in partial or total long bone arthroplasties used in tumour or complex revision surgery. These implants differ considerably in the coating method, total silver content, and silver release rates. Safety issues, such as the occurrence of argyria, have been a cause for concern, and the efficacy of silver coatings in terms of preventing PJI is also controversial. The application of silver coatings is uncommon on parts of implants intended for cementless fixation in host bone, but this option might be highly desirable since the modification of implant surfaces in order to improve osteoconductivity can also increase bacterial adhesion. Therefore, an optimal silver content that inhibits bacterial colonization while maintaining osteoconductivity is crucial if silver were to be applied as a coating on parts intended for bone contact. This review summarizes the different methods used to apply silver coatings to arthroplasty components, with a focus on the amount and duration of silver release from the different coatings; the available experience with silver-coated implants that are in clinical use today; and future strategies to balance the effects of silver on bacteria and eukaryotic cells, and to develop silver-coated titanium components suitable for bone ingrowth. Cite this article: Bone Joint J 2021;103-B(3):423–429

Aims. The STRYDE nail is an evolution of the PRECICE Intramedullary Limb Lengthening System, with unique features regarding its composition. It is designed for load bearing throughout treatment in order to improve patient experience and outcomes and allow for simultaneous bilateral lower limb lengthening. The literature published to date is limited regarding outcomes and potential problems. We report on our early experience and raise awareness for the potential of adverse effects from this device. Methods. This is a retrospective review of prospective data collected on all patients treated in our institution using this implant. We report the demographics, nail accuracy, reliability, consolidation index, and cases where concerning clinical and radiological findings were encountered. There were 14 STRYDE nails implanted in nine patients (three male and six female) between June 2019 and September 2020. Mean age at surgery was 33 years (14 to 65). Five patients underwent bilateral lengthening (two femoral and three tibial) and four patients unilateral femoral lengthening for multiple aetiologies. Results. At the time of reporting, eight patients (13 implants) had completed lengthening. Osteolysis and periosteal reaction at the junction of the telescopic nail was evident in nine implants. Five patients experienced localized pain and swelling. Macroscopic appearances following retrieval were consistent with corrosion at the telescopic junction. Tissue histology was consistent with effects of focal metallic wear debris. Conclusion. From our early experience with this implant we have found the process of lengthening to be accurate and reliable with good regenerate formation and consolidation. Proposed advantages of early load bearing and the ability for bilateral lengthening are promising. We have, however, encountered concerning clinical and radiological findings in several patients. We have elected to discontinue its use to allow further investigation into the retrieved implants and patient outcomes from users internationally. Cite this article: Bone Joint J 2021;103-B(6):1168–1172

Peri-prosthetic osteolysis and subsequent aseptic loosening is the most common reason for revising total hip replacements. Wear particles originating from the prosthetic components interact with multiple cell types in the peri-prosthetic region resulting in an inflammatory process that ultimately leads to peri-prosthetic bone loss. These cells include macrophages, osteoclasts, osteoblasts and fibroblasts. The majority of research in peri-prosthetic osteolysis has concentrated on the role played by osteoclasts and macrophages. The purpose of this review is to assess the role of the osteoblast in peri-prosthetic osteolysis. In peri-prosthetic osteolysis, wear particles may affect osteoblasts and contribute to the osteolytic process by two mechanisms. First, particles and metallic ions have been shown to inhibit the osteoblast in terms of its ability to secrete mineralised bone matrix, by reducing calcium deposition, alkaline phosphatase activity and its ability to proliferate. Secondly, particles and metallic ions have been shown to stimulate osteoblasts to produce pro inflammatory mediators in vitro. In vivo, these mediators have the potential to attract pro-inflammatory cells to the peri-prosthetic area and stimulate osteoclasts to absorb bone. Further research is needed to fully define the role of the osteoblast in peri-prosthetic osteolysis and to explore its potential role as a therapeutic target in this condition. Cite this article: Bone Joint J 2013;95-B:1021–5

Aims. The aim of this study was to conduct the largest low contact stress (LCS) retrieval study to elucidate the failure mechanisms of the Porocoat and Duofix femoral component. The latter design was voluntarily recalled by the manufacturer. Materials and Methods. Uncemented LCS explants were divided into three groups: Duofix, Porocoat, and mixed. Demographics, polyethylene wear, tissue ingrowth, and metallurgical analyses were performed. Results. In 104 implants, a decrease in the odds of loosening and an increase in metallosis and tissue staining in the Duofix group relative to Porocoat group was detected (p = 0.028). There was an increased presence of embedded metallic debris in the Duofix group (p < 0.001). Decreased tissue ingrowth was associated with the Duofix surface (p < 0.001). The attached beads had reduced microhardness, indicative of adverse thermal processing, which resulted in bead shedding, particulate debris, and metallosis. Conclusion. Hydroxyapatite coating of the LCS femoral component produced unexpected results and led to its recall. The root cause was likely a combination of retained alumina grit and a reduction in bead microhardness (mechanical strength) resulting in increased particle debris, metallosis, and early revision. The Duofix LCS femoral component was not equivalent to the Porocoat version despite its approval through the Food and Drug Administration (FDA) 510(k) equivalance approval process. Regulation of the introduction of modified existing devices needs to be improved and the Duofix LCS should have been considered to be a new device for which equivalence had not been demonstrated at the point of introduction. Cite this article: Bone Joint J 2019;101-B:1248–1255

Aims. To assess the effect of age on clinical outcome and revision rates in patients who underwent total ankle arthroplasty (TAA) for end-stage ankle osteoarthritis (OA). Methods. A consecutive series of 811 ankles (789 patients) that underwent TAA between May 2003 and December 2013 were enrolled. The influence of age on clinical outcome, including the American Orthopaedic Foot and Ankle Society (AOFAS) hindfoot score, and pain according to the visual analogue scale (VAS) was assessed. In addition, the risk for revision surgery that includes soft tissue procedures, periarticular arthrodeses/osteotomies, ankle joint debridement, and/or inlay exchange (defined as minor revision), as well as the risk for revision surgery necessitating the exchange of any of the metallic components or removal of implant followed by ankle/hindfoot fusion (defined as major revision) was calculated. Results. A significant improvement in the AOFAS hindfoot score and pain relief between the preoperative assessment and the last follow-up was evident. Age had a positive effect on pain relief. The risk for a minor or major revision was 28.7 % at the mean follow-up of 5.4 years and 11.0 % at a mean follow-up of 6.9 years respectively. The hazard of revision was not affected by age. Conclusion. The clinical outcome, as well as the probability for revision surgery following TAA, is comparable between younger and older patients. The overall revision rate of the Hintegra total ankle is comparable with other three component designs. TAA should no longer be reserved for low demand elderly patients, but should also be recognized as a viable option for active patients of younger age. Cite this article: Bone Joint J 2020;102-B(7):925–932

Aims

The aims of this study were to determine the success of a reconstruction algorithm used in major acetabular bone loss, and to further define the indications for custom-made implants in major acetabular bone loss.