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Bone & Joint Research
Vol. 10, Issue 3 | Pages 156 - 165
1 Mar 2021
Yagi H Kihara S Mittwede PN Maher PL Rothenberg AC Falcione ADCM Chen A Urish KL Tuan RS Alexander PG

Aims

Periprosthetic joint infections (PJIs) and osteomyelitis are clinical challenges that are difficult to eradicate. Well-characterized large animal models necessary for testing and validating new treatment strategies for these conditions are lacking. The purpose of this study was to develop a rabbit model of chronic PJI in the distal femur.

Methods

Fresh suspensions of Staphylococcus aureus (ATCC 25923) were prepared in phosphate-buffered saline (PBS) (1 Ă— 109 colony-forming units (CFUs)/ml). Periprosthetic osteomyelitis in female New Zealand white rabbits was induced by intraosseous injection of planktonic bacterial suspension into a predrilled bone tunnel prior to implant screw placement, examined at five and 28 days (n = 5/group) after surgery, and compared to a control aseptic screw group. Radiographs were obtained weekly, and blood was collected to measure ESR, CRP, and white blood cell (WBC) counts. Bone samples and implanted screws were harvested on day 28, and processed for histological analysis and viability assay of bacteria, respectively.


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_10 | Pages 76 - 76
1 May 2016
Tei K Kihara S Shimizu T Matsumoto T Kurosaka M Kuroda R
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Introduction

Recently, tibial insert design of cruciate-substituting (CS) polyethylene insert is employed. However, in vivo kinematics of using CS polyethylene insert is still unclear. In this study, it is hypothesized that CS polyethylene insert leads to stability of femolo-tibial joint as well as posterior-stabilized (PS) polyethylene insert, even if PCL is sacrificed after TKA. The purpose of this study is an investigation of in vivo kinematics of femolo-tibial joint with use of CS polyethylene insert before and after PCL resction using computer assisted navigation system intra-operatively in TKA.

Materials and Methods

Twenty-four consecutive patients who had knees of osteoarthritis with varus deformity were investigated in this study. All TKAs (Triathlon, Stryker) were performed using computer assisted navigation system. In all patients, difference between extension and flexion gap was under 3mm after bony cut of femur and tibia. During surgery, CS polyethylene tibial trial insert were inserted after trial implantation of femoral and tibial components, before and after resection of PCL, respectively. The kinematic parameters of the soft-tissue balance, and amount of coronal (valgus/varus), sagittal (anterior/posterior) and rotational relative movement between femur and tibia were obtained by interpreting kinematics, which display tables throughout the range of motion (ROM) (Figure1). During record of kinematics, the surgeon gently lifted the experimental thigh three times, flexing the hip and knee. In each ROM (30, 45, 60, 90, max degrees), the data were analyzed with paired t-test, and an ANOVA test, and mean values were compared by the multiple comparison test (Turkey HSD test) (p < 0.05).


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_7 | Pages 78 - 78
1 May 2016
Chinzei N Hayashi S Kanzaki N Hashimoto S Kihara S Haneda M Takeuchi K Kuroda R Kurosaka M
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Introduction

Failure of acetabular components has been reported to lead to large bone defects, which determine outcome and management after revision total hip arthroplasty (THA). Although Kerboull-type (KT) plate (KYOCERA Medical Corporation, Kyoto, Japan) has been used for compensating large bone loss, few studies have identified the critical risk factors for failure of revision THA using a KT plate. Therefore, the aim of this study is to evaluate the relationship between survival rates for radiological loosening and the results according to bone defect or type of graft.

Patients and methods

This study included patients underwent revision THA for aseptic loosening using cemented acetabular components with a KT plate between 2000 and 2012. Bone defects were filled with beta Tricalcium phosphate (TCP) granules between 2000 and 2003 and with Hydroxyapatite (HA) block between 2003 and 2009. Since 2009, we have used femoral head balk allografts. Hip function was evaluated by using the Japanese Orthopaedic Association (JOA) score and University of California, Los Angeles (UCLA) activity. Acetabular defects were classified according to the American Academy of Orthopedic Surgeons (AAOS) classification. The postoperative and final follow-up radiographs were compared to assess migration of the implant. Kaplan–Meier method for cumulative probabilities of radiographic failure rate, and the comparison of survivorship curves for various subgroups using the log-rank test were also evaluated. Logistic regression was performed to examine the association of such clinical factors as the age at the time of operation, body mass index, JOA score, UCLA activity score, and AAOS classification with radiographic failure. Odds ratios (ORs) and 95% CIs were calculated. Multivariate analysis was performed to adjust for potential confounders by clinical factors. Values of p < 0.05 were considered significant.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_34 | Pages 442 - 442
1 Dec 2013
Muratsu H Kirizuki S Kihara S Takeoka Y Matsumoto T Maruo A Miya H Kuroda R Kurosaka M
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[Introduction]

Rapid increase of aged population has been one of major issue affecting national health care plan in Japan. In 2006, Japanese Orthopaedic Association indicated a new clinical entity of musculoskeletal ambulation disorder symptom complex (MADS) to define the higher risk of fall and ambulatory disability in the elderly population caused by musculoskeletal disorders. Osteoarthritis of the knee is one of major cause of MADS. The number of patients with MADS underwent total knee arthroplasty (TKA) had been increased in Japan, and also expected to increase worldwide in the near future. The effectiveness of TKA for the patient with MADS would be a key issue for the patient satisfaction in TKA. In the present study, we analyzed the influence of pre-operative factors on the ambulatory functions in the patients of primary TKA.

[Material & Method]

132 patients with osteoarthritic knees implanted with posterior-stabilized (PS) TKAs were subjected to this study. There were 113 female and 19 male patients. The mean age of the patients was 73.6 years (range, 59 to 87 years). Patients were pre-operatively subjected to 2 functional performance tests which were essential tests for MADS diagnosis. Firstly, 3 meter timed up and go test (TUG) was used to evaluate ambulation ability. Secondary one leg standing time (ST) with open eyes was measured with both operated and non-operated leg to assess balancing ability. MADS was diagnosed if TUG and ST were not less than 11 seconds and/or less than 15 seconds respectively. The influence of each pre-operative factor was evaluated simple linear regression analysis (p < 0.05). Pre-operative factors consisted of age, sex, weight, height, BMI, standing femoro-tibial angle (FTA) and active knee range of motion.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_34 | Pages 180 - 180
1 Dec 2013
Takeoka Y Muratsu H Kihara S Matsumoto T Miyaji N Oshima T Maruo A Miya H Kuroda R Kurosaka M
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Objective

The goal of total knee arthroplasty (TKA) is to achieve a stable and well-aligned tibiofemoral and patello-femoral (PF) joint, aiming at long-term clinical patient satisfaction. The surgical principles of both cruciate retaining (CR) and posterior stabilized (PS) TKA are accurate osteotomy and proper soft tissue balancing. We have developed an offset-type tensor, and measured intra-operative soft tissue balance under more physiological joint conditions with femoral component in place and reduced PF joint.

In this study, we measured intra-operative soft tissue balance and assessed the early post-operative knee joint stability quantitatively, and compared these parameters between CR and PS TKA.

Material and Method

Seventy patients with varus osteoarthritis of the knee underwent TKAs (35 CR TKAs: CR and 35 PS TKAs: PS). Mean varus deformity in standing position was 9.8 degrees in CR, and 10.7 degrees in PS (p = 0.45). All TKAs were performed by a single surgeon with measured resection technique. The external rotation of posterior femoral condyle osteotomy was performed according to surgical epicondylar axis (SEA) in pre-operative CT. We measured intra-operative soft tissue balance using an offset-type tensor with 40 lbs of joint distraction force at 0, 10, 30, 45, 60, 90, 120 and 135 degrees of flexion. The joint component gap (mm) and varus angle (degrees) were measured at each flexion angle.

Four weeks after operation, we evaluated the knee stability at extension by varus and valgus stress radiography using Telos (10 kg) and at flexion by epicondylar view with 1.5 kg weight at the ankle. We measured joint separation distance at medial as medial joint looseness (MJL) and at lateral as lateral joint looseness (LJL). Joint looseness was defined as the average of MJL and LJL.

Intra-operative measurements and post-operative joint stabilities were compared between CR and PS using unpaired t-test.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_15 | Pages 217 - 217
1 Mar 2013
Kihara S Muratsu H Matsumoto T Kirizuki S Maruo A Miya H Kuroda R Kurosaka M
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Introduction

Rapid increase of aged population has been one of major issue affecting national health care plan in Japan. In 2006, Japanese Orthopaedic Association proposed the clinical entity of musculoskeletal ambulation disorder symptom complex (MADS) to define the elderly population with high risk of fall and ambulatory disability caused by musculoskeletal disorders. Osteoarthritis of the knee is one of major cause of MADS. The number of patients with MADS underwent total knee arthroplasty (TKA) had been increased in Japan, and also expected to increase worldwide in the near future. The effectiveness of TKA for the patient with MADS has not been well evaluated. In the present study, we analyzed the early post-operative functional recovery after TKA using 2 simple performance tests to diagnose MADS.

Material & Method

Fifty patients with varus type osteoarthritic knees implanted with posterior-stabilized (PS) TKAs were subjected to this study. There were 44 female and 6 male patients. The mean age of the patients was 71.6 years (range, 59 to 84 years). Patients were subjected to 2 functional performance tests which were essential tests for MADS diagnosis. Firstly, 3 meter timed up and go test (TUG) was used to evaluate ambulation. Secondary one leg standing time with open eyes was measured to assess balancing ability. 2 tests were performed pre-operatively, 2 weeks after surgery and at discharge (23.8 days po). MADS was defined to be diagnosed if TUG and one leg standing time was not less than 11 seconds and/or less than 15 seconds respectively. Each parameter was compared among at above mentioned three time points -using a repeated measured analysis of variance (p<0.05).