Increased Risk of Periprosthetic Fractures and Revision Arthroplasty in Patients Undergoing Shoulder Arthroplasty With a History of Prior Fragility Fractures: A Matched Cohort Analysis.

INTRODUCTION: As rates of anatomic and reverse total shoulder arthroplasty (SA) continue to grow, an increase in the number of osteoporotic patients undergoing SA, including those who have sustained prior fragility fractures, is expected. The purpose of this study was to examine short-term, implant-related complication rates and secondary fragility fractures after SA in patients with and without a history of fragility fractures. METHODS: A propensity score-matched retrospective cohort study was done using the PearlDiver database to characterize the effect of antecedent fragility fractures in short-term complications after SA. Rates of revision SA, periprosthetic fractures, infection, and postoperative fragility fractures were evaluated using multivariate logistic regression analysis. Risks of these complications were also studied in patients with and without preoperative osteoporosis treatment. Statistical significance was set at P < 0.05. RESULTS: A total of 91,212 SA patients were identified, with 13,050 (14.3%) experiencing a fragility fracture within the 3 years before SA. Two years after SA, there were increased odds of periprosthetic fracture (odds ratio [OR] 2.24, 95% confidence interval [CI] 1.68 to 2.99), fragility fracture (OR 9.11, 95% CI 8.43 to 9.85), deep infection (OR 1.68, 95% CI 1.34 to 2.12), and all-cause revision SA (OR 1.68, 95% CI 1.44 to 1.96) within those patients who had experienced a fragility fracture within 3 years before their SA. Patients who were treated for osteoporosis with bisphosphonates and/or vitamin D supplementation before their SA had similar rates of postoperative periprosthetic fractures, fragility fractures, and all-cause revision SA to those who did not receive pharmacologic treatment. CONCLUSION: Sustaining a fragility fracture before SA portends substantial postoperative risk of periprosthetic fractures, infection, subsequent fragility fractures, and all-cause revision SA at the 2-year postoperative period. Pharmacotherapy did not markedly decrease the rate of these complications. These results are important for surgeons counseling patients who have experienced prior fragility fractures on the risks of SA.

Single Wedge Femoral Stem Designs are Associated With a Higher Risk for Revision After Cementless Primary Total Hip Arthroplasty.

BACKGROUND: Cementless total hip arthroplasty (THA) femoral stems are the most commonly selected prostheses in the United States. Optimal stem geometry remains controversial with excellent survivorship reported for many designs. We compared cause-specific stem revision of single-wedge versus double-wedge designs from a multicenter US cohort. METHODS: Data from an integrated healthcare network's total joint replacement registry were used to conduct a cohort study. Primary elective cementless THAs were identified (2001 to 2018). Implant exposure groups were classified by design geometry using the system proposed by Khanuja et al. Type 1 single-wedge (n = 11,082) and type 2 double-wedge (n = 32,380) designs were compared, and other design types were excluded; the final study cohort comprised 43,462 THAs. Cause-specific multivariable Cox regressions were used to evaluate risk for revision due to infection or aseptic reasons, including loosening, instability, periprosthetic fracture, or other reasons. RESULTS: After adjustment for covariates, a higher aseptic revision risk was observed for type 1 when compared to type 2 designs (hazard ratio = 1.91, 95% confidence interval = 1.33-2.75). When looking at specific revision reasons, revision for aseptic loosening (hazard ratio = 3.46, 95% confidence interval = 2.24-5.34) was higher for type 1 versus type 2 designs. No differences were found for septic revision, instability, periprosthetic fracture, or revisions for other reasons. CONCLUSIONS: Type 1 single-wedge designs were found to have a higher risk of revision due to aseptic loosening relative to type 2 double-wedge designs. Femoral stem geometry should be considered when selecting a cementless femoral implant. LEVEL OF EVIDENCE: Level III.

Results of 200 Consecutive Ceramic-on-Ceramic Cementless Hip Arthroplasties in Patients Up To 50 Years of Age: A 5-24 Years of Follow-Up Study.

BACKGROUND: Ceramic-on-ceramic (CoC) bearings due to their mechanical properties can be used in primary total hip arthroplasty (THA) especially in young patients requiring a long-lasting implant. The goal of this study is to analyze the results of a series of 200 consecutive CoC THAs in patients aged 50 years or less at the time of surgery. METHODS: A retrospective study was conducted on the first 200 consecutive CoC arthroplasties performed using the direct lateral approach on 105 females and 81 males (14 bilateral cases) with an average age of 44.2 (16-50) years. The diagnosis was primary or post-traumatic osteoarthritis in 94 cases, avascular necrosis of the femoral head in 47, displaced intracapsular femoral neck fracture in 29, osteoarthritis secondary to developmental dysplasia of the hip/Legg-Calvè-Perthes disease/slipped capital femoral epiphysis in 20, and rheumatic diseases in 10 cases. The preoperative Harris Hip Score was 32.5 on average (range 15-55). All the implants were cementless. In 177 THAs the coupling was alumina-on-alumina, and in 23 cases the coupling was AMC-on-AMC (alumina matrix composite). RESULTS: Twenty-five patients with 28 THAs were lost at the final follow-up, 2 stems were revised due to subsidence, 1 cup was revised due to malposition, 1 femoral head was changed because of impingement, and 1 THA was revised for periprosthetic infection. Three patients sustained a Vancouver B1 periprosthetic femoral fracture. At the final follow-up (mean 14.9 years; minimum 5 years to maximum 24 years), 172 THAs were eligible for clinical and radiographic evaluation: none was revised for wear and/or breakage of the ceramic components. Harris Hip Score rose up to a mean value of 90.1 (52-100). CONCLUSION: The present report demonstrates that CoC coupling offers excellent long-term results in THA performed in young patients with very low wear and no adverse effects caused by the material.

A minimum 20-year outcome of 100 consecutive alumina-on-alumina arthroplasties performed by a single surgeon.

BACKGROUND:: Ceramic-on-ceramic (CoC) is currently a viable bearing combination in primary total hip arthroplasty (THA) and, due to its mechanical properties, it can be used in young patients requiring a long-lasting implant. The aim of this study is to report the results of a series of CoC THAs at a minimum 20 years follow-up. METHODS:: A retrospective study was conducted on the 1st 100 consecutive alumina-on-alumina arthroplasties performed by a single surgeon on 51 females and 40 males with an average age of 60.7 years. The mean preoperative Harris Hip Score was 35. The press-fit cup consisted of a pure titanium core with a titanium alloy mesh. Both the inlay and the head were made of dense polycrystalline surgical-grade alumina. The 32-mm femoral head was anchored on 3 different femoral components. RESULTS:: 19 patients with 22 THAs were died or lost, 2 anatomic cementless stems were revised due to sinking, 1 THA was revised for periprosthetic infection. 2 patients sustained a Vancouver B1 periprosthetic femoral fracture. None of the 78 THAs eligible for this study were revised for wear, breakage, noise of the ceramic components. None of the cups, none of the cemented stems, none of the cementless straight stems failed. HHS raised up to a mean value of 95. CONCLUSIONS:: The present report demonstrates that CoC coupling offers minimal wear at a long-term follow-up. Further studies are needed to evaluate whether the modern ceramic composites will confirm such excellent results in total hip replacement.

Results of revision of total hip arthroplasty for alumina ceramic-on-ceramic bearing fracture.

PURPOSE: The purpose of this study was to compare the results of revision total hip arthroplasty after fracture of primary ceramic components using different type of revision bearing surfaces. METHODS: We analysed the results of 16 patients with a follow-up more than 3 years after first revision. 6 were revised to ceramic-on-ceramic (CoC) bearing, 9 to metal-on-polyethylene (MoP) and 1 to ceramic-on-cross-linked polyethylene (CoXLP) bearing. RESULTS: The mean follow-up was 87 months. Patients with revision to CoC had higher Harris Hip Score (HHS) of 89 points in comparison to the patients with revision to MoP with 84 points. Radiographic examinations revealed visible eccentric polyethylene wear with osteolysis in 3 out of 9 patients revised to MoP. There were no detrimental x-ray changes in patients revised to CoC components. CONCLUSIONS: We consider CoC as the best option at revision operation for ceramic component fracture.

Obturación con óxido de zinc-eugenol y formocresol en casos de fractura de instrumento intraconducto: seguimiento de 54 casos durante 8 años / Obturation with zinc oxide-eugenol and formocresol in cases of intracanal fractured instruments: 8 years follow-up study of 54 cases

Introducción: El objetivo de este estudio es presentar los resultados del seguimiento durante 8 años de 54 casos de instrumentos rotos intraconducto, que no pudieron ser removidos y/o sobrepasados, y que fueron obturados con óxido de zinc-eugenol (ZOE) y formocresol. Material y métodos: Se incluyeron 54 pacientes con fractura de instrumentos en conductos radiculares de dientes posteriores, 23 no presentaban lesión periapical y 31 tenían lesión. Los instrumentos fracturados tenían longitudes de 2-4 mm en tercio apical y no pudieron ser removidos y/o sobrepasados con ninguna técnica. Los conductos fueron preparados al borde del instrumento fracturado, hasta un calibre 45 en dirección apical con técnica telescópica, irrigando con hipoclorito de sodio al 3% y desmineralizando con 0,25 ml de EDTA al 16%, lavados con 3 ml de solución fisiológica y secados con puntas de papel, se obturaron utilizando 0,01 ml de formocresol, 0,05 ml de eugenol mezclados con óxido de zinc y cono de gutapercha calibre 45 mediante condensación lateral. Los conductos restantes fueron instrumentados telescópicamente y obturados con gutapercha y ZOE mediante condensación lateral. Resultados: Se realizaron controles clínicos y radiográficos a uno, tres, cinco y ocho años. Al año, los casos oscilaron entre 83,9-95,7% asintomáticos y negativos a la percusión, fístula ausente entre 93,5-100% y sin lesión periapical de 32,3-91,3%. A tres años, 96,8-100% asintomáticos y negativos a la percusión, ausencia de fístula y sin lesión de 80,6-95,7%. A cinco años, 96,8-100% asintomáticos y negativos a la percusión, ausencia de fístula y 93,5- 100% sin lesión. A ocho años, 100% asintomáticos, negativos a percusión, ausencia de fistula y 93,5-95,7% sin lesión. Conclusiones: La utilización de ZOE-formocresol es una alternativa terapéutica exitosa en casos de instrumentos fracturados que no pudieron ser removidos y/o sobrepasados

Introduction: The aim of this study is to present the results of monitoring over 8 years of 54 cases of intracanal broken instruments, which could not be removed and/or bypassed, and were sealed with zinc oxide-eugenol (ZOE) and formocresol. Material and methods: Fifty-four patients with broken instruments in root canals of posterior teeth, 23 had no periapical lesion and 31 had periapical lesion. Fractured instruments were had lengths of 2-4 mm in apical third and were not removed and/or exceeded with any technique. Root canals were prepared at the edge of the fractured instrument using the telescope technique up to 45 file. Irrigation was performed with sodium hypochlorite 3% and 0.25 ml of 16% EDTA. Then, the root canals were washed with saline solution 3 ml and dried with paper points. Obturation was carried out using 0.01 ml formocresol plus 0.05 ml of eugenol mixed with zinc oxide and a guttapercha master cone number 45 using lateral condensation. Remaining canals were telescopically instrumented and filled with guttapercha and ZOE by lateral condensation. Results: Clinical and radiographic controls at one, three, five and eight years were performed. After one year, 83.9-95.7% were asymptomatic and negative to percussion, absent fistula between 93,5-100%, without periapical lesion 32,3-91,3%. After three years 96,8-100% asymptomatic and negative on percussion, absence of fistula, without periapical lesion 80,6-95,7%. At five years 96,8-100% asymptomatic and negative on percussion, absence of fistula and 93,5- 100% without periapical lesion. In eight years, 100% asymptomatic, negative percussion and absence of fistula and 93,5-95,7% without periapical lesion. Conclusions: The use of zinc oxide-eugenol and formocresol is a successful therapeutic option in cases of fractured instruments that could not be removed and/or exceeded

Do alumina matrix composite bearings decrease hip noises and bearing fractures at a minimum of 5 years after THA?

BACKGROUND: Ceramic-on-ceramic bearing couples are theoretically attractive in total hip arthroplasty (THA) because of low wear, but concerns regarding ceramic fracture and squeaking have arisen. Improved material properties of newer alumina matrix composite (AMC) materials, known as Delta ceramics, may reduce these risks. In addition, the use of thinner liners and larger femoral heads may be helpful clinically to lower the rate of dislocation. However, limited short-term clinical results are available and intermediate-term effects are unclear. QUESTIONS/PURPOSES: (1) What is the frequency of bearing-related complications (dissociation, fracture, and noise) with ceramic-on-ceramic AMC bearings in cementless THA? (2) What other complications arose in patients treated with these bearings? (3) What are the Harris hip scores (HHS) and survivorship free from reoperation and revision at a minimum of 5 years after cementless THA performed with AMC bearings? METHODS: Over a 9-month period in 2009, one surgeon performed 125 THAs, of which 100 (80% of the total) were performed with cementless, AMC bearings. During the period in question, the exclusion criteria for this implant were primary THAs with severe acetabular or femoral bone defect and revision THAs. Of these, 94 hips (95%) in 91 patients were available for analysis at a minimum of 5 years (range, 5-6 years), because five patients (six hips) had died. Mean age at the time of arthroplasty was 55 ± 14 years. Prostheses with an identical design and Biolox(®) Delta ceramics were used in all patients. Noise was classified into squeaking, clicking, grinding, and popping. Ceramic fracture, dislocation, and any other complications associated with the use of AMC ceramics were also investigated. Clinical evaluation included the modified HHS preoperatively and at each followup. Survivorship free from reoperation and revision was calculated using the Kaplan-Meier method. RESULTS: Of 91 patients, four developed bearing-related complications, including one with liner dissociation despite initial square seating and three with clicking. No patients had ceramic fractures. A single event of perioperative dislocation occurred in one patient and postoperative periprosthetic fracture occurred in two hips. Mean HHS improved from 56 to 93 points at the final followup (p < 0.001). Survivorship at 5 years free from reoperation and revision was 96.8% and 97.9%, respectively. CONCLUSIONS: Improved material properties combined with the possible use of larger diameter heads make AMC ceramics a promising alternative bearing option with seemingly comparable clinical outcomes reported by others with conventional ceramic bearings. Despite these encouraging results, however, meticulous technical precautions such as square seating and proper impaction in particular should be taken during liner insertion, because we did observe one liner dissociation and several patients with hip noises. LEVEL OF EVIDENCE: Level IV, therapeutic study.

Association of Bisphosphonate Use and Risk of Revision After THA: Outcomes From a US Total Joint Replacement Registry.

BACKGROUND: Total hip arthroplasty (THA) is often performed in patients who are older and may take bisphosphonates to treat a variety of conditions, most commonly osteoporosis. However, the clinical effects of bisphosphonate use on patients who have undergone THA are not well described. QUESTIONS/PURPOSES: (1) Is bisphosphonate use in patients with osteoarthritis undergoing primary THA associated with a change in the risk of all-cause revision, aseptic revision, or periprosthetic fracture compared with patients not treated with bisphosphonates? (2) Does the risk of bisphosphonate use and revision and periprosthetic fracture vary by patient bone mineral density and age? METHODS: A retrospective cohort study of 12,878 THA recipients for the diagnosis of osteoarthritis was conducted; 17.8% of patients were bisphosphonate users. Data sources for this study included a joint replacement registry (93% voluntary participation) and electronic health records and an osteoporosis screening database with complete capture of cases as part of the Kaiser Permanente integrated healthcare system. The endpoints for this study were revision surgery for any cause, aseptic revision, and periprosthetic fracture. The exposure of interest was bisphosphonate use; patients were considered users if prescriptions were continuously refilled for a period equal to or longer than 6 months. Bone quality (based on dual-energy x-ray absorptiometery ordered based on the National Osteoporosis Foundation's clinical guidelines taken within 5 years of the THA) and patient age (< 65 versus ≥ 65 years) were evaluated as effect modifiers. Patient, surgeon, and hospital factors were evaluated as confounders. Cox proportional hazards models were used. Hazard ratios (HRs) and 95% confidence intervals (CIs) were determined. RESULTS: Age- and sex-adjusted risks of all-cause (HR, 0.50; 95% CI, 0.33-0.74; p < 0.001) and aseptic revision (HR, 0.53; 95% CI, 0.34-0.81; p = 0.004) was lower in bisphosphonate users than in nonusers. The adjusted risk of periprosthetic fractures in patients on bisphosphonates was higher than in patients not on bisphosphonates (HR, 1.92; 95% CI, 1.13-3.27; p = 0.016). Lower risks of all-cause revision and aseptic revision were observed in patients with osteopenia (HR, 0.49; 95% CI, 0.29-0.84; and HR, 0.53; 95% CI, 0.29-0.99, respectively) and osteoporosis (HR, 0.22; 95% CI, 0.08-0.62; and HR, 0.33; 95% CI, 0.11-0.99, respectively). CONCLUSIONS: Patients considered bisphosphonate users who underwent THA had a lower risk for revision surgery. Bisphosphonate use was associated with a higher risk of periprosthetic fractures in younger patients with normal bone quantity. Evaluation of bone quality and bisphosphonate use for the diagnosis of osteoporosis is encouraged in patients with osteoarthritis who are candidates for primary THA. Further research is required to determine the optimal duration of therapy because long-term bisphosphonate use has been associated with atypical femur fractures. LEVEL OF EVIDENCE: Level III, therapeutic study.

Intermittent PTH administration and mechanical loading are anabolic for periprosthetic cancellous bone.

The purpose of this study was to determine the individual and combined effects on periprosthetic cancellous bone of intermittent parathyroid hormone administration (iPTH) and mechanical loading at the cellular, molecular, and tissue levels. Porous titanium implants were inserted bilaterally on the cancellous bone of adult rabbits beneath a loading device attached to the distal lateral femur. The left femur received a sham loading device. The right femur was loaded daily, and half of the rabbits received daily PTH. Periprosthetic bone was evaluated up to 28 days for gene expression, histology, and µCT analysis. Loading and iPTH increased bone mass by a combination of two mechanisms: (1) Altering cell populations in a pro-osteoblastic/anti-adipocytic direction, and (2) controlling bone turnover by modulating the RANKL-OPG ratio. At the tissue level, BV/TV increased with both loading (+53%, p < 0.05) and iPTH (+54%, p < 0.05). Combined treatment showed only small additional effects at the cellular and molecular levels that corresponded to a small additive effect on bone volume (+13% compared to iPTH alone, p > 0.05). This study suggests that iPTH and loading are potential therapies for enhancing periprosthetic bone formation. The elucidation of the cellular and molecular response may help further enhance the combined therapy and related targeted treatment strategies.

A biomechanical comparison of periprosthetic femoral fracture fixation in normal and osteoporotic cadaveric bone.

Several techniques are described for fixation of Vancouver B1 femoral shaft fractures after total hip arthroplasty. Twenty-four femurs were scanned by dual x-ray absorptiometry scanned and matched for bone mineral density. Femurs were implanted with a cemented simulated total hip prosthesis with a simulated periprosthetic femur fracture distal to the stem. Fractures were fixed with Synthes (Paoli, Pa) 12-hole curved plates and 4 different constructs proximally. Each construct was loaded to failure in axial compression. Constructs with locking and nonlocking screws demonstrated equivalent loads at failure and were superior in load at failure compared with cables. Cable constructs failed proximally. No proximal failures occurred in specimens fixed with screws and cables. A combination of locked or nonlocked screws and supplemental cable fixation is recommended for the treatment of Vancouver B1 periprosthetic femur fractures.