Agreement and accuracy of radiographic assessment using a decision aid for medial Oxford partial knee replacement: multicentre study

( Takafumi Hiranaka ),( Ryosuke Furuhashi ),( Kenichiro Takashiba ),( Takao Kodama ),( Kazuhiko Michishita ),( Hiroshi Inui ),( Eita Togashi ) 대한슬관절학회 2022 대한슬관절학회지 Vol.34 No.-

Background: Indication for mobile-bearing partial knee replacement (PKR) is made on the basis of a radiological decision aid. This study aimed to reveal the inter-rater reproducibility and accuracy of the decision aid when used by experienced surgeons. Patients and methods: Anonymised radiographic image sets (anteroposterior, lateral, varus/valgus stress in 20° knee flexion, and skyline views) from 20 consecutive patients who underwent knee replacement were assessed by 12 experienced surgeons. Agreements of each section and accuracy were compared by intra-operative inspection of the status of the anterior cruciate ligament (ACL) and medial and lateral cartilage according to the protocol of Radiographic Assessment for Medial Oxford PKR. Fleiss’ kappa (κ) values were used as a statistical measure. Results: Full-thickness medial cartilage had the best agreement between the surgeons (κ = 94.7%) and best accuracy (94.2%). Although functioning ACL (90.8%), intact cartilage (91.7%) and full-thickness lateral cartilage defects (86.1%) were accurately diagnosed, diagnoses of deficient ACL (up to 42.5%) and partial-thickness lateral cartilage defects (11.7%) were poor; they were sometimes misdiagnosed as being intact. Moreover, agreement of lateral and valgus stress radiographs regarding intact MCL function, as well as the overall decision, was considered to be inadequate (κ = 0.47, 0.58 and 0.51, respectively). Conclusions: Although the radiological aid is useful for selection of patients who are likely to be suitable for PKR, surgeons should still carefully assess the lateral weight-bearing area for partial-thickness loss and deficiency of the ACL because they were sometimes overlooked by surgeons using radiographs. MRI will be helpful to improve the accuracy of determination of Oxford PKR indication.

Kinematically Aligned Oxford Unicompartmental Knee Arthroplasty Using the Microplasty Instrumentation System

Takafumi Hiranaka,Takaaki Fujishiro,Motoki Koide,Koji Okamoto 대한정형외과학회 2023 Clinics in Orthopedic Surgery Vol.15 No.4

This technical note demonstrates kinematically aligned Oxford unicompartmental knee arthroplasty using the Microplasty instrumentation system with custom-made devices. The medial joint line is evaluated preoperatively; if it is aligned and parallel with the lateral joint line, they are considered to comprise the coronal knee joint line (CJL). In this case, the coronal inclination of a spoon gauge inserted into the medial joint space indicates the CJL. Otherwise, an accessory spoon is inserted and connected to the medial spoon to refer to the posterior condylar line, which is considered the CJL. The tibial cutting block is then connected without changing the inclination of the spoon and the coronal tilt of the tibial extramedullary rod is adjusted, which is implemented with a custom-made ankle yoke. The remainder of the steps is then identical to the conventional Microplasty procedure. This technique can imitate the cutting line to the CJL, which might be considered ideal from mechanical and kinematic perspectives.

Clinical Results of Dual SC Screw: A Mini-Sliding Hip Screw with an Anti-rotating Screw for Femoral Neck Fractures

Takafumi Hiranaka,Toshikazu Tanaka,Kenjiro Okumura,Takaaki Fujishiro,Rika Shigemoto,Shotaro Araki,Ryo Okada,Ryohei Nako,Koji Okamoto 대한정형외과학회 2021 Clinics in Orthopedic Surgery Vol.13 No.4

Background: Dual SC screw (DSCS) is a unique concept internal fixation device consisting of a sliding screw and barrel assembly that enables compression force to be applied to the femoral neck fracture side. There are two types of barrels: a thread barrel and a plate barrel that has a one-holed side plate to prevent varus deformity. We report clinical results of the application of a DSCS with combined use of a thread barrel screw as an anti-rotational screw and a plate barrel screw as a compression hip screw. Methods: We used DSCS for femoral neck fractures in 196 hip joints of 190 patients between November 2005 and June 2017. Among them, 70 hips in 66 patients (13 men and 53 women; mean age, 73.2 years) were followed up for at least 24 months. There were 53 nondisplaced fractures (Garden’s classification stage 1 or 2) and 17 displaced fractures (stage 3 or 4). We evaluated the postoperative walking ability of the patients who were followed up for at least 24 months and examined details of all complications. Results: The mean follow-up period was 37.4 months (range, 24–144 months). Forty-two (64%) out of the 66 patients who were followed up for at least 2 years were able to walk independently with or without a cane. The incidence of complications was 11.5% in nondisplaced fractures and 17.5% in displaced fractures, and arthroplasty was required in 5.8% and 5.0%, respectively. The most frequent complication was secondary displacement including cutout and shortening of the femoral neck, but no implants showed varus displacement. Conclusions: The application of DSCS for the treatment of femoral neck fractures had satisfactory results. The complication rate was low, and there was no postoperative varus displacement of DSCS in either displaced or nondisplaced fractures. We suggest DSCS is a reliable option for both displaced and nondisplaced femoral neck fractures.

A Modified Under-Vastus Approach for Knee Arthroplasty with Anatomical Repair of Soft Tissue

Takafumi Hiranaka,Toshikazu Tanaka,Takaaki Fujishiro,Kensuke Anjiki,Naosuke Nagata,Daiya Kitazawa,Ken Kotoura,Koji Okamoto 대한정형외과학회 2019 Clinics in Orthopedic Surgery Vol.11 No.4

The under-vastus approach (UVA) is a modification of the conventional subvastus approach for knee arthroplasty. Our modified UVA allows the muscles to be spared while offering good exposure of the operative field and facilitating anatomical repair of the capsule and fascia. A medial parapatellar incision is made and the vastus medialis fascia is incised along the same line. The muscle belly is not incised but detached from the surrounding fascia and retracted laterally. The suprapatellar pouch capsule is then laterally incised under the vastus muscles. The patella can then be easily retracted laterally and adequate exposure is possible. After the procedure, both capsule and fascia can be anatomically repaired. We use this approach for all primary arthroplasties in our practice. There has been no case in which an additional muscle incision was required, and there were no intraoperative complications. The modified UVA allows for excellent exposure of the operative field as well as muscle retention in both primary total and unicompartmental knee arthroplasties.

Manipulation of Tibial Component to Ensure Avoidance of Bearing Separation from the Vertical Wall of Tibial Component in Oxford Unicompartmental Arthroplasty

Takafumi Hiranaka,Toshikazu Tanaka,Kenjiro Okimura,Takaaki Fujishiro,Rika Shigemoto,Shotaro Araki,Ryo Okada,Ryohei Nako,Tomoyuki Kamenaga,Koji Okamoto 대한정형외과학회 2021 Clinics in Orthopedic Surgery Vol.13 No.1

In Oxford unicompartmental knee arthroplasty, the relationship between the mobile bearing and the vertical wall of the tibial tray is important in preventing bearing dislocation. Separation of the bearing from the vertical wall can cause spinning of the bearing with an increased risk of subsequent dislocation. We report on intraoperative adjustment of the tibial tray performed to prevent the bearing from spinning. After tibial and femoral bone cutting and adjustment of the flexion and extension gap, the trial bearing is inserted and the bearing-vertical wall distance is evaluated before the preparation using the tibial template and bearing trial. In the case of separation, it can be resolved by medialization with or without rotational adjustment. The technique is useful and can be easily performed, it is therefore recommendable for all cases of Oxford mobile-bearing unicompartmental arthroplasty.

A Novel Technique for Varus Tibial Cutting for Oxford Unicompartmental Knee Arthroplasty

Takafumi Hiranaka,Toshikazu Tanaka,Takaaki Fujishiro,Kenjiro Okimura,Rika Shigemoto,Shotaro Araki,Ryo Okada,Ryohei Nako,Koji Okamoto 대한정형외과학회 2020 Clinics in Orthopedic Surgery Vol.12 No.4

To reduce the stress on the medial tibial cortex and to decrease the risk of fracture, a varus cut of the tibia appears to be a reasonable alternative to the orthogonal cut by conventional methods. We present a new instrument and procedure, which enables a varus tibial cut for Oxford unicompartmental knee arthroplasty. We used a custom-made, slidable fixator instead of the standard fixator to set the extramedullary rod on the leg. We also made a numeric formula and a chart to arrange the varus cutting angle using the length of the mediolateral shift of the distal end and the longitudinal extension length of the extramedullary tibial rod. A varus cut up to 4.5° can be controlled. This technique is a simple and useful means of obtaining a varus tibial cut for Oxford unicompartmental knee arthroplasty.

Second-Look Arthroscopic Findings and Clinical Outcomes after Adipose-Derived Regenerative Cell Injection in Knee Osteoarthritis

Yuma Onoi,Takafumi Hiranaka,Yuichi Hida,Takaaki Fujishiro,Koji Okamoto,Tomoyuki Matsumoto,Ryosuke Kuroda 대한정형외과학회 2022 Clinics in Orthopedic Surgery Vol.14 No.3

Background: To evaluate the clinical outcomes and second-look arthroscopic findings after intra-articular adipose-derived regenerative cell (ADRC) injection as treatment for knee osteoarthritis (OA). Methods: ADRCs were administered to 11 patients (19 knees; mean age, 61.7 years) with knee OA. Subcutaneous adipose tissue was harvested by liposuction from both thighs, and arthroscopic lavage was performed, followed by ADRC injection (mean dose, 1.40 × 107 cells) into the synovial fluid. Outcome measures included the Knee Injury and Osteoarthritis Outcome Score, Lysholm score, and visual analog scale score. Arthroscopic examinations were performed to assess the International Cartilage Repair Society cartilage injury grade preoperatively and overall repair postoperatively. Noninvasive assessments were performed at baseline and at 1-, 3-, and 6-month follow-ups; arthroscopic assessments were performed at baseline and at 6 months. Results: All outcome measures significantly improved after treatment. This improvement was evident 1 month after treatment and was sustained until the 6-month follow-up. Data from second-look arthroscopy showed better repair in low-grade cartilage lesions than in lesions with a greater degree of damage. No patients demonstrated worsening of Kellgren-Lawrence grade, and none underwent total knee arthroplasty during this period. Conclusions: Clinical outcomes were improved in patients with knee OA after ADRC administration. Cartilage regeneration was more effective in smaller damaged lesions than in bigger lesions.

Accurate and Easy Measurement of Sliding Distance of Intramedullary Nail in Trochanteric Fracture

Nobuaki Chinzei,Takafumi Hiranaka,Takahiro Niikura,Takaaki Fujishiro,Shinya Hayashi,Noriyuki Kanzaki,Shingo Hashimoto,Yoshitada Sakai,Ryosuke Kuroda,Masahiro Kurosaka 대한정형외과학회 2015 Clinics in Orthopedic Surgery Vol.7 No.2

In daily clinical practice, it is essential to properly evaluate the postoperative sliding distance of various femoral head fixation devices (HFD) for trochanteric fractures. Although it is necessary to develop an accurate and reproducible method that is unaffected by inconsistent postoperative limb position on radiography, few studies have examined which method is optimal. Therefore, the purpose of this study is to prospectively compare the accuracy and reproducibility of our four original methods in the measurement of sliding distance of the HFD. Methods: Radiographs of plastic simulated bone implanted with Japanese proximal femoral nail antirotation were taken in five limb postures: neutral, flexion, minute internal rotation, greater external rotation, and flexion with external rotation. Orthopedic surgeons performed five measurements of the sliding distance of the HFD in each of the flowing four methods: nail axis reference (NAR), modified NAR, inner edge reference, and nail tip reference. We also assessed two clinical cases by using these methods and evaluated the intraclass correlation coefficients. Results: The measured values were consistent in the NAR method regardless of limb posture, with an even smaller error when using the modified NAR method. The standard deviation (SD) was high in the nail tip reference method and extremely low in the modified NAR method. In the two clinical cases, the SD was the lowest in the modified NAR method, similar to the results using plastic simulated bone. The intraclass correlation coefficients showed the highest value in the modified NAR method. Conclusions: We conclude that the modified NAR method should be the most recommended based on its accuracy, reproducibility, and usefulness.

Comparison of the Sliding and Femoral Head Rotation among Three Different Femoral Head Fixation Devices for Trochanteric Fractures

Nobuaki Chinzei,Takafumi Hiranaka,Takahiro Niikura,Mitsuo Tsuji,Ryosuke Kuroda,Minoru Doita,Masahiro Kurosaka 대한정형외과학회 2015 Clinics in Orthopedic Surgery Vol.7 No.3

Background: Recently, various femoral head fixation devices (HFDs) for trochanteric fractures have become available. However, there are some cases in which femoral head rotation with excessive sliding of the HFD is observed and it is often followed by cutout. The purpose of this study is to compare the ability of the three types of HFDs to prevent femoral head rotation. Methods: Between July 2005 and December 2009, 206 patients aged over 60 years with trochanteric fractures who had undergone surgical treatment using a short femoral nail in our institution were enrolled into the study. We used the gamma 3 nail (GMN) as the screw-type HFD in 66 cases, the gliding nail (GLN) as a non-cylindrical blade in 76 cases, and the proximal femoral nail antirotation (PFNA) as a cylindrical blade in 64 cases. The sliding length of HFDs and the occurrence of femoral head rotation were evaluated by assessing radiographs as the main outcome, and the results were compared among these devices. Results: A comparison of the degree of sliding in the GMN group showed that femoral head rotation was observed significantly more frequently in cases with rotation. Further, it appeared that femoral head rotation occurred more frequently in comminuted fractures. However, no significant differences between the sliding lengths of the different HFDs were observed among three groups. Femoral head rotation was observed in 15 cases of GMN (22.7%), 0 case of GLN, and 5 case of PFNA (7.8%). Significant differences with regard to the occurrence of femoral head rotation were observed among the three groups. Furthermore, significant differences were also observed between GLN and PFNA with respect to the occurrence of femoral head rotation. Conclusions: The ability to stabilize femoral head appears to be greater with blade-type materials than with screw-type materials. Furthermore, we believe that a non-cylindrical blade is preferable to a cylindrical blade for the surgical treatment of comminuted, unstable trochanteric fractures in order to prevent femoral head rotation and cut-out.

Is simultaneous bilateral unicompartmental knee arthroplasty and total knee arthroplasty better than simultaneous bilateral total knee arthroplasty?

( Naosuke Nagata ),( Takafumi Hiranaka ),( Koji Okamoto ),( Takaaki Fujishiro ),( Toshikazu Tanaka ),( Anjiki Kensuke ),( Daiya Kitazawa ),( Ken Kotoura ) 대한슬관절학회 2023 대한슬관절학회지 Vol.35 No.-

Introduction This retrospective study aims to clarify if there are benefits of performing unicompartmental knee arthroplasty (UKA) on just one indicated side in patients who undergo simultaneous bilateral knee arthroplasty. Materials and methods We compared 33 cases of simultaneous bilateral UKA/total knee arthroplasty (TKA) (S-UT) with 99 cases of simultaneous bilateral TKA (S-TT). Comparison included blood tests [C-reactive protein (CRP), albumin, and D-dimer], the incidence of deep vein thrombosis (DVT), range of motion (ROM), and clinical scores before and 1 year after surgery. Results Clinical scores were not significantly different between the groups. The postoperative flexion angle was significantly better in UKA sides. Blood tests showed that the S-UT had a significantly higher albumin value at 4 and 7 days after surgery. The CRP value at 4 and 7 days, and the D-dimer value at 7 and 14 days after surgery were significantly lower in the S-UT. The S-UT had significantly lower incidence of DVT. Conclusions In cases of bilateral arthroplasty, if there is an indication on only one side, a better flexion angle can be obtained by UKA on that side, and with less surgical invasion. Moreover, the incidence of DVT is low, which is considered to be a benefit of performing UKA on just one side.