The lexicon for periprosthetic bone loss versus osteolysis after cervical disc arthroplasty: a systematic review

Background Periprosthetic bone loss is a common observation following arthroplasty. Recognizing and understanding the nature of bone loss is vital as it determines the subsequent performance of the device and the overall outcome. Despite its significance, the term “bone loss” is often misused to describe inflammatory osteolysis, a complication with vastly different clinical outcomes and treatment plans. Therefore, the goal of this review was to report major findings related to vertebral radiographic bone changes around cervical disc replacements, mitigate discrepancies in clinical reports by introducing uniform terminology to the field, and establish a precedence that can be used to identify the important nuances between these distinct complications. Methods A systematic review of the literature was conducted following PRISMA guidelines, using the keywords “cervical,” “disc replacement,” “osteolysis,” “bone loss,” “radiograph,” and “complications.” A total of 23 articles met the inclusion criteria with the majority being retrospective or case reports. Results Fourteen studies reported periprosthetic osteolysis in a total of 46 patients with onset ranging from 15–96 months after the index procedure. Reported causes included: metal hypersensitivity, infection, mechanical failure, and wear debris. Osteolysis was generally progressive and led to reoperation. Nine articles reported non-inflammatory bone loss in 527 patients (52.5%), typically within 3–6 months following implantation. The reported causes included: micromotion, stress shielding, and interrupted blood supply. With one exception, bone loss was reported to be non-progressive and had no effect on clinical outcome measures. Conclusions Non-progressive, early onset bone loss is a common finding after CDA and typically does not affect the reported short-term pain scores or lead to early revision. By contrast, osteolysis was less common, presenting more than a year post-operative and often accompanied by additional complications, leading to revision surgery. A greater understanding of the clinical significance is limited by the lack of long-term studies, inconsistent terminology, and infrequent use of histology and explant analyses. Uniform reporting and adoption of consistent terminology can mitigate some of these limitations. Executing these actionable items is critical to assess device performance and the risk of revision. Level of Evidence IV Diagnostic: individual cross-sectional studies with consistently applied reference standard and blinding.

Continuous periprosthetic bone loss but preserved stability for a collum femoris-preserving stem: follow-up of a prospective cohort study of 21 patients with dualenergy X-ray absorptiometry and radiostereometric analysis with minimum 8 years of follow-up

Background and purpose — We previously described a decrease in bone mineral density (BMD) in the calcar region 2 years after insertion of the collum femoris-preserving (CFP) stem, but the implants were stable. Now we have examined the long-term changes in periprosthetic BMD and stability of the CFP stem. Patients and methods — We conducted a minimum 8-year follow-up of 21 patients from our original investigation. We examined periprosthetic BMD by dual-energy X-ray absorptiometry (DEXA) and implant stability by radiostereometric analysis (RSA). Results — Between 2 and 8 years 1 stem was revised due to aseptic loosening. Between 2 and 8 years we found a 14% (95% confidence interval [CI] 9–19) reduction in BMD in Gruen zone 6 and 17% (CI 6–28) in Gruen zone 7. From baseline the reduction in BMD was 30% (CI 23–36) in Gruen zone 6, 39% (CI 31–47) in Gruen zone 7, and 19% (CI 14–23) in Gruen zone 2. Between 2 and 8 years, RSA (n = 17) showed a mean translation along the stem axis of 0.02mm (CI –0.02 to 0.06) and a mean rotation around the stem axis of 0.08° (CI –0.26 to 0.41). From baseline mean subsidence was 0.07 mm (CI –0.16 to 0.03) and mean rotation around the stem axis was 0.23° (CI –0.23 to 0.68) at 8 years. Interpretation — There was continuous loss of proximomedial BMD at 8 years while the CFP stem remained stable. Proximal periprosthetic bone loss cannot be prevented by this stem.

Zoledronic Acid for Periprosthetic Bone Mineral Density Changes in Patients With Osteoporosis After Hip Arthroplasty—An Updated Meta-Analysis of Six Randomized Controlled Trials

Introduction: Periprosthetic bone mineral density (BMD) loss following total hip arthroplasty (THA) may threaten the survival of the implant, especially in patients with osteoporosis. Zoledronic acid (ZA) is the representative of the third generation of bisphosphonates, which were effective in reducing bone loss in conditions associated with accelerated bone turnover. The aim of this study was to evaluate the efficacy and safety of ZA in patients with osteoporosis after THA.Methods: Randomized controlled trials (RCTs) associated with ZA and THA were searched from the MEDLINE, PubMed, EMBASE, Wanfang database, and the Web of Science (August 2021). Other methods, such as hand search and email request were also tried. The methodological quality was assessed by the Risk of Bias (RoB) 2.0. Relevant data were abstracted from the included RCTs and authors were contacted when necessary.Results: In this study, six RCTs involving a total of 307 patients were finally included and analyzed. The pooled data demonstrated that significantly less periprosthetic BMD loss in Gruen zone seven had occurred in the ZA-treated patients than in the control patients at 3 months (mean difference [MD] = 4.03%; 95% CI: 0.29–7.76%; P = 0.03), 6 months (MD = 7.04%; 95% CI: 2.12–11.96%; P = 0.005), and 12 months (MD = 7.12%; 95% CI: 0.33–13.92%; P = 0.04). The Harris Hip Score (HHS) was also significantly increased in ZA group at 6 and 12 months after operation (P = 0.03 and P = 0.02, respectively). Influenza-like symptom was found related to the usage of ZA [relative risk (RR) = 7.03, P < 0.0001].Conclusion: A meta-analysis of six RCTs suggested that ZA was beneficial in maintaining the periprosthetic BMD in patients with osteoporosis at 6 and 12 months after THA. In addition, the HHS was significantly improved in patients treated with ZA. However, the short length of follow-up of the available studies resulted in the lack of analyses regarding the survival of implants including the rate of aseptic loosing, periprosthetic fracture, and revision. It still needs to be determined in research with longer follow-up period.Clinical Trial Registration:Researchregistry.com, identifier: reviewregistry1087.

The Lasting Effect of Discontinuing Zoledronic Acid On Periprosthetic Bone Mineral Density Five Years After Total Hip Arthroplasty

Background: Previous study has shown that a short-term use of zoledronic acid (ZA) after cementless total hip arthroplasty (THA) significantly increases bone mineral density (BMD) over the proximal femur and inhibits bone turnover markers (BTMs) after two years. However, could the discontinuation of ZA have a lasting effect is of interest.Method: This is an extension study of a two-year prospective randomized controlled trial on 54 cementless THA treated with either two doses of ZA or placebo. We compared BTMs [alkaline phosphatase (ALP); osteocalcin (OC); procollagen 1 intact N-terminal propeptide (P1NP)], serum calcium, renal function, radiological findings, and functional outcomes (Harris hip score and UCLA activity score) from baseline to 5 years post-THA in 49 patients, and periprosthetic BMD of the seven Gruen zones in 19 patients.Result: All patients had well-functioning hip prostheses, normal renal function, and normal serum calcium levels at 5-year follow-up. At the fifth year, the BMD levels were not statistically different between the two groups, but the change in BMD from baseline (BMD change ratios) in ZA group were significantly increased in zone 2, 4, and 6 as compared with control group. Parallel to that, in ZA group, levels of ALP were significantly lower at the fifth year; OC were significantly lower at the second and the fifth year; P1NP were significantly lower from 6 weeks to 2 years as compared with those in control group.Conclusion: This study demonstrates the lasting effect of a two-dose ZA given within one year after THA on bone metabolism and periprosthetic BMD at five years. The short-term dosing of ZA followed by a 4-year drug holiday had no adverse events and resulted in significant inhibition of periprosthetic bone loss and BTMs.Trial Registration:This extension study on a randomized, open label, single-center clinical trial was conducted under Institutional Review Board of Chang Gung Memorial Hospital Protocol Records 98-1150A3; 105-1296C1; 105-7004D, and was registered July 19th, 2016 on public registry ClinicalTrials.gov trial registration number NCT02838121.

Volume and Distribution of Periprosthetic Bone Cysts in the Distal Tibia and Talus before Early Revision of Total Ankle Arthroplasty

Periprosthetic osteolysis is a common complication following total ankle arthroplasty (TAA). However, understanding of osteolysis volume and distribution is still evolving, undermining efforts to reduce the incidence of osteolysis via bone remodeling. We obtained data on the characteristics of osteolysis developing within the distal tibia and talus after TAA. Three-dimensional computed tomography (3D-CT) reconstructions of 12 patients who underwent HINTEGRA TAA were performed. We identified 27 volumes of interest (VOIs) in the tibia and talus and used statistical methods to identify the characteristics of osteolysis in the VOIs. The osteolysis volume was significantly larger in the talus than in the tibia (162.1 ± 13.6 and 54.9 ± 6.1 mm3, respectively, p = 0.00). The extent of osteolysis within the peri-prosthetic region was greater than within other regions (p < 0.05). Particularly, in the talus, the region around the talar pegs exhibited 24.2 ± 4.5% more osteolysis than any other talar region (p = 0.00). Our results may suggest that extensive osteolysis within the peri-prosthetic region reflects changes in stress flow and distribution, which vary according to the design and placement of the fixation components. This is the first study to report 3D osteolysis patterns after TAA. Careful planning of TAA design improvements may reduce the incidence of osteolysis. Our results will facilitate the further development of TAA systems.

Histological evaluation of periprosthetic infection using HOES scale and CD15 expression analysis at the stage of the hip revision arthroplasty

Background.The effectiveness improvement and standardization of the methods of histological diagnosing periprosthetic infection (PPI) is an urgent task in the treatment of complications after large joint arthroplasty. Purpose of the study— Histopathological evaluation of the infection involvement of periprosthetic tissues at the stage of revision arthroplasty for deep infection of the hip using HOES scale and immunohistochemical analysis of CD15 expression.Materials and Methods.A single-center prospective study was performed on the clinical intraoperative material obtained at the stage of revision arthroplasty of the hip in 27 patients at the age of 65 (55÷69) years. The group of examination included patients with acute and chronic forms of deep periprosthetic infection. Light-optical microscopic investigation of the samples of periprosthetic connective-tissue membrane and bone tissue from the foci of infectious involvement was made on paraffin sections stained with hematoxylin and eosin; with the immunohistochemical reaction to determine the expression of CD15 neutrophil granulocyte markers. HOES Scale for pathohistological assessment was used in order to objectify osteomyelitis signs in periprosthetic bone tissue.Results. The signs of acute and chronic stages of periprosthetic osteomyelitis were observed in 9/16 patients with PPI chronic course within 1–30 months of postoperative period, from one to 18 months after manifestation of the symptoms. The signs of subsided osteomyelitis were determined in 12/27 patients with PPI of acute and chronic forms. Infected periprosthetic membranes were found in 19/27 clinical cases in the early and longterm time periods after arthroplasty surgery. A direct significant correlation was revealed between histopathological signs of infecting the periprosthetic bone and the connective-tissue periprosthetic membrane, especially strong one in patients with acute and chronic PPI osteomyelitis.Conclusion. The use of HOES Scale and the analysis of CD15 expression ensure the objectivity of PPI histological diagnosing. The results obtained indicate an increased risk of osteomyelitis development in patients with chronic periprosthetic infection after the hip arthroplasty.

Monitoring the reduction and maintenance of periprosthetic bone tissue in cementless primary hip endoprosthesis with alendronate therapy

Loss of periprosthetic bone tissue in primary hip endoprostheses is common in clinical practice. This loss can be progressive and in extreme conditions can jeopardize the longevity of the prosthesis. In order to monitor the function of Alendronate therapy for bone maintenance, the study included 50 patients with implanted total cement-free hip endoprosthesis (TPH). The first group of 25 patients received Alendronate, calcium and vitamin D3 orally postoperatively. The second group of 25 patients were examined postoperatively without therapy. Patients were followed by radiographic and dual-energy X-ray absorptiometry (DXA) at 6 and 12 months. The study showed that in patients with TPH there was a difference in the X-ray findings as well as occurrence of osteolysis in certain Gruen zones, which was confirmed by changes in the state of bone mineral density (BMD) and bone mineral content (BMC) in the interval between 6 and 12 months using the DXA method. Alendronate therapy after TPH implantation allows reduction of periprosthetic bone mass loss, maintenance of bone mineralization and implant hardening.