Reliability of Total Nucleated Cell Counts in the Setting of Hip Arthroplasty

Author(s):  
Lauren N Pearson ◽  
Robert L Schmidt ◽  
Kenneth Cahoon ◽  
Christopher E Pelt

Abstract Background Total nucleated cell (TNC) count and differential are used to classify joint effusions as inflammatory or noninflammatory. Further diagnostic evaluation and management is contingent on this classification. TNC count can be measured by automated analyzers or by manual assessment using a hemocytometer. Studies have raised concerns regarding the accuracy of TNC counts measured by automated instruments, particularly in the setting of joint arthroplasty. The objective of this study was to determine whether metallosis, a complication of total hip arthroplasty in which metal debris accumulates in periprosthetic tissues and synovial fluid, is associated with inaccurate TNC counts in synovial fluid. Methods We compared the accuracy of cell counts measured by the Sysmex XN-1000 and Beckman Coulter Iris iQ200 with the gold standard of manual assessment using a hemocytometer in synovial fluid from patients with suspected metallosis and in fluid obtained from controls from patients with native joints and a history of arthroplasty for other indications. Results TNC counts produced by automated analyzers were associated with increased levels of discordance (relative to manual counts) in patients with metallosis. Metallosis was not associated with increased levels of discordance for RBC counts or WBC differentials. The Sysmex XN flagged all but 1 metallosis sample for manual verification of the results. Conclusions Automated methods are generally reliable for analysis of synovial fluid. TNC counts can be inaccurate in the context of metallosis following total hip arthroplasty. Laboratories should correlate automated cell counts with a microscopic assessment of the specimen, as recommended by instrument manufacturers.

2021 ◽  
Vol 9 ◽  
pp. 205031212110147
Author(s):  
Nobuhiko Sumiyoshi ◽  
Kazuhiro Oinuma ◽  
Yoko Miura

Background: Adverse reactions to metal debris are significant complications after metal-on-metal total hip arthroplasty. Recently, late appearances of adverse reactions to metal debris and subsequent need for reoperations have been reported with small-diameter head metal-on-metal devices. We retrospectively investigated mid-term clinical outcomes of small-head metal-on-metal total hip arthroplasty. Methods: We reviewed 159 hips in 139 patients who had a small-head metal-on-metal total hip arthroplasty (M2a Taper; Biomet, Warsaw, IN) with a minimum 5-year follow-up and documented postoperative complications. Results: Focal osteolysis in either the femur or acetabulum was observed in 12 hips (7.5%, 44 months after surgery on average), with pseudotumor observed in 8 hips (5%, 120 months after surgery on average). Four hips (2.5%) had dislocations (84 months after surgery on average) and six hips (3.8%, 122 months after surgery on average) underwent reoperation. Conclusion: Small-head metal-on-metal total hip arthroplasty is associated with a high degree of complications at mid-term follow-up period. Considering this, we discourage the use of metal-on-metal total hip arthroplasty regardless of head size.


2014 ◽  
Vol 8 (1) ◽  
pp. 56-59 ◽  
Author(s):  
Motoki Sonohata ◽  
Masaru Kitajima ◽  
Syunsuke Kawano ◽  
Masaaki Mawatari

The risk of periprosthetic joint infection from hematogenous bacterial seeding is increased in patients undergoing dental procedures that facilitate the development of bacteremia. We herein report the case of a patient without a history of dental procedures who suffered from an acute metastatic infection of a hip prosthesis by the oral bacterium Streptococcus mutans 18 months after undergoing revision total hip arthroplasty. The patient was successfully treated by two-stage revision surgery. It is important to realize that the efficacy of antibiotic prophylaxis against joint infections has not yet been convincingly proven. As a result, optimal dental hygiene and regular dental visits may be more important than antibiotic prophylaxis for maintaining joint health. Therefore, orthopedic surgeons should educate patients with joint prostheses about good oral health.


2020 ◽  
Vol 8 (2) ◽  
pp. 119-128
Author(s):  
Alexandr I. Avdeev ◽  
Igor A. Voronkevich ◽  
Dmitrii G. Parfeev ◽  
Anton N. Kovalenko ◽  
David G. Pliev ◽  
...  

Background. Conservative treatment options for hip dysplasia and hip dislocation in early childhood allow for good results in cases of a timely diagnosis. The preferred treatment option for patients with hip dislocation in adulthood is total hip joint replacement. The shortening osteotomy, proposed by T. Paavilainen, allows the surgeon to restore the difference in the lengths of the lower extremities during arthroplasty of the hip joint. However, according to the results of the Paavilainen technique, as presented by Russian orthopedic surgeons, the problem of nonunion of the greater trochanter fragment with the diaphysis of the femur remains unresolved, as evidenced by a massive group of clinical cases. Aim. The aim of this study was to identify factors affecting the consolidation of bone fragments after osteotomy of the greater trochanter, according to T. Paavilainen, during total hip arthroplasty and evaluate their significance after fixation with cerclage screws in comparison with a special trochanteric fork-plate. Materials and methods. The present study includes 208 cases that were treated at the Russian Scientific Research Institute of Traumatology and Orthopedics named after R.R. Vreden from 2003 to 2019 using various fixation techniques of the greater trochanter fragment. Patients were divided into two groups depending on their type of fixation. The quality of consolidation of a greater trochanter fragment with the femur was assessed during a follow-up period of six months or longer. The fragment of the greater trochanter was divided into the part that was not in contact with the diaphysis, or A, and the part that was in contact with the diaphysis, or B. We assessed the effect of the absolute value of the contact between fragments, the B/A ratio, the distance between the points of insertion of the screws into the diaphyseal part of the femur, the quality of the bone by the modified Barnet-Nordin index, and the history of previous surgical interventions on this joint on the consolidation. Results. When the part of the greater trochanter was in contact with the diaphysis of the femur (B) was less than 3.5 cm, the risk ratio of nonunion of the greater trochanter fragment with the diaphysis of the femur increased. Also, a significant factor is the index of the contact of the greater trochanter fragment (B/A less than 1) with the diaphysis of the femur using the T. Paavilainen technique. In addition, the presence of surgical intervention in the hip joint history significantly increases the relative risk (RR) of nonunion of the greater trochanter fragment with the diaphysis of the femur with this method of shortening osteotomy of the femur. Conclusion. In the absence of timely diagnosis and conservative treatment of children with hip dislocation, reconstructive-plastic techniques on the hip joint do not allow the achievement of proper results and increase the complexity of total hip arthroplasty. According to the results of this study, the absolute value of the contact between fragments (B), the index of the greater trochanter contact with the diaphysis of the femur, and the history of previous surgical intervention on this joint are objective tools for the prognostic assessment of the probability of fragment unions during total hip arthroplasty with the T. Paavilainen technique.


2016 ◽  
Vol 10 (1) ◽  
pp. 105-110 ◽  
Author(s):  
Motoki Sonohata ◽  
Masaru Kitajima ◽  
Shunsuke Kawano ◽  
Masaaki Mawatari

Background: Total hip arthroplasty (THA) for poliomyelitis is a problematic procedure due to difficulty in positioning the cup of the prosthesis in the true acetabulum and the risk of dislocation after THA due to the low muscle tone. Methods: We herein present a case of bilateral hip pain with a history of poliomyelitis. Radiograph showed bilateral hip osteoarthritis caused by hip dysplasia due to residual poliomyelitis in right hip joint or developing dysplasia of the hip joint in left hip joint. THA was performed to bilateral hip joints. Results: Six years after bilateral THA, bilateral hip pain significantly improved. Additionally, the muscle strength on the paralyzed right side partially improved. However, the muscle strength on the non-paralyzed left side did not significantly improve. No complications related to the surgery were observed. Conclusion: Promising early results were obtained for THA in our patient with residual poliomyelitis. However, surgeons should pay attention to the potential development of complications concerning THA that may arise due to the residual poliomyelitis.


2020 ◽  
Vol 9 (10) ◽  
pp. 3349
Author(s):  
Henrik C. Bäcker ◽  
Chia H. Wu ◽  
David Krüger ◽  
Clemens Gwinner ◽  
Carsten Perka ◽  
...  

Introduction: The effect of different bearings on synovial white blood cell (WBC) count and polymorphonuclear percentage (PMN%) in aspirations remains unclear. Therefore, this study investigates the impact of aseptic Metal-on-Metal (MoM) bearing on synovial fluid. Methods: We searched our arthroplasty registry for aseptic painful THAs with MoM bearings between 2011 and 2018. Then, a case-matched control group was selected with septic and aseptic Total Hip Arthroplasty (THA) with ceramic on a polyethylene (PE) bearing. The matching criteria consisted of gender, age +/−10 years, and time of aspiration (+/−2years). Periprosthetic Joint Infection (PJI) was defined according to the Infectious Diseases Society of America (IDSA), and Musculoskeletal Infection Society (MSIS) using bacterial cultures, sonication and histology. Results: In total, 19 patients who underwent hip aspiration with MoM bearing were identified. Five patients had to be excluded due to insufficient synovial fluid obtained (n = 2) or bacterial growth after sonication that was initially negative with the standard microbiological cultures (n = 3). As such, 14 were included. These patients were matched with 14 aseptic and 14 septic THAs with ceramic on a PE bearing, which constituted the control group. The mean serum chrome level was 20.0 ± 15.5 nmol/L and cobalt level 18.4 ± 22.1 nmol/L. The synovial WBC and PMN% varied significantly between MoM bearing group and the aseptic THA ceramic PE group (both p < 0.001), as well as the septic THA group (WBC p = 0.016, PMN% p < 0.001). Furthermore, the septic THA group had significantly higher CRP values than the aseptic MoM group (p = 0.016). Conclusion: MoM bearing shows significantly higher synovial WBC and PMN% when compared to aseptic THA with ceramic on PE bearing above the MSIS cut-off. This is an important consideration when diagnosing periprosthetic joint infection using the MSIS guidelines.


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