Publications by authors named "Norishige Iizawa"

17 Publications

  • Page 1 of 1

Maturation process of regenerated tissues after single-stage simultaneous autologous particulated cartilage implantation and open wedge high tibial osteotomy for articular cartilage defects with medial osteoarthritis of bilateral knees: a case report.

BMC Musculoskelet Disord 2021 May 31;22(1):502. Epub 2021 May 31.

Department of Orthopaedic Surgery, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo, 113-8603, Japan.

Background: Open wedge high tibial osteotomy (OWHTO) is an effective treatment option for young and middle-aged active patients with medial unicompartmental knee osteoarthritis (OA). In addition, particulated cartilage implantation has been developed as a simple procedure for cartilage regeneration. Thus, to improve the OWHTO outcomes, a single-stage, simultaneous bilateral knee arthroscopic particulated cartilage implantation with OWHTO was performed.

Case Presentation: A 60-year-old male patient presented with severe bilateral knee pain, with grade 2 varus knee OA of the Kellgren-Lawrence classification. Primary arthroscopic evaluations based on the International Cartilage Repair Society grading system showed grade 3c articular cartilage defects of 1.5 cm in diameter at the center of the bilateral medial femoral condyles. Following bilateral OWHTO, the healthy cartilage tissue was harvested from the lateral wall of the unilateral femoral intercondylar notch and minced with the cartilage processor. Then, subchondral drillings and cartilage fragment implantations into the bilateral defects were performed arthroscopically. One year postsurgery, second-look arthroscopy findings revealed that the defects were filled with cartilage-like tissues. The maturation process of the regenerated tissues was confirmed with T2 mapping magnetic resonance imaging during the 3-year follow-up period. The patient could walk without a cane, and all Knee Injury and Osteoarthritis Outcome Score parameters were improved without any correction loss in 3 years.

Conclusions: This is the first report to evaluate the maturation process of the implanted particulated cartilage tissue with T2 mapping magnetic resonance imaging for 3 years. The effect of chondral resurfacing procedure with OWHTO remains unclear; however, the implantation of arthroscopic particulated cartilage fragments is a single-stage and less-invasive procedure. This treatment could regenerate cartilage-like tissue in the present case. Therefore, this additional procedure could potentially improve the long-term outcomes of OWHTO.
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http://dx.doi.org/10.1186/s12891-021-04368-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8165777PMC
May 2021

An Isolated Iliac Wing Stress Fracture in a Male Marathon Runner: A Case Report.

JBJS Case Connect 2021 04 19;11(2). Epub 2021 Apr 19.

Department of Orthopaedic Surgery, Nippon Medical School, Tokyo, Japan.

Case: A 49-year-old man, who had started jogging 3 months before his first participation in a marathon race, presented with acute pain and difficulty walking that began during the marathon race. Tumors and bone metabolism factors were ruled out by blood examination and various imaging findings. Isolated iliac wing fatigue fracture was diagnosed and treated with conservative therapy.

Conclusion: This is the first English-literature report we know of an isolated iliac wing stress fracture in a male marathon runner without underlying disease. Our study highlights the importance of considering this rare fracture when diagnosing patients presenting with iliac pain.
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http://dx.doi.org/10.2106/JBJS.CC.20.00541DOI Listing
April 2021

The Optimal Distraction Force to Evaluate Tibiofemoral Joint Gaps in Posterior Stabilized-Total Knee Arthroplasty.

J Nippon Med Sch 2021 Jan 16. Epub 2021 Jan 16.

Department of Orthopaedic Surgery, Nippon Medical School.

BackgroundObtaining well-balanced soft tissues has been known to be important to achieve natural knee kinematics post-total knee arthroplasty. In conventional procedures, the soft tissue balance has been evaluated using the spacer block or the lamina spreader. However, these procedures depend on the surgeons' experiences and are not quantitative. This study aims to measure the mechanical properties of knee soft tissue with a new ligament balancer and to determine the optimal distraction force to evaluate the tibiofemoral joint gaps in total knee arthroplasty.MethodsThis study included 30 medial knee osteoarthritic patients, who were consecutively scheduled to undergo posterior stabilized-total knee arthroplasty. The mean age of the patients was 73 ± 9.6 years old during surgery, and the mean hip-knee-ankle angle was 13.1 ± 6.5° in varus. After distal femoral and proximal tibial resection, the tibiofemoral joint gaps under several amounts of distraction forces in extension and at 90° in flexion were measured. The load-displacement curves in extension and in flexion were drawn with these data, and the stability range, which was defined as the shift range from the toe region to the linear region in the curves, was calculated.ResultsThe stability ranges were calculated to be 160 N in extension and 140 N in flexion.ConclusionsThese displacement forces were considered optimal loads to evaluate the tibiofemoral joint gaps during surgery and to obtain knee stability post-total knee arthroplasty.
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http://dx.doi.org/10.1272/jnms.JNMS.2021_88-519DOI Listing
January 2021

The Influence of Posterior Cruciate Ligament Resection on Tibiofemoral Joint Gap in Varus Osteoarthritic Knees.

J Knee Surg 2020 Jul 13. Epub 2020 Jul 13.

Department of Orthopaedic Surgery, Nippon Medical School, Bunkyo-ku, Tokyo, Japan.

Posterior cruciate ligament (PCL) resection during posterior-stabilized total knee arthroplasty (PS-TKA) has been reported to preferentially increase the tibiofemoral joint gap in flexion compared with extension. However, previous assessments of the joint gaps have been performed after bone resection and medial soft tissue release. Thus, these procedural steps may have the potential to influence soft tissue balance. In native knees, soft tissue laxity is generally greater in the lateral compartment than in the medial compartment both with the knee in extension and in flexion. Some surgeons may retain this natural soft tissue balance with less aggressive medial release during TKA. We performed this study to evaluate the impact of the PCL resection on the extension and flexion gaps in the absence of bone resection or medial soft tissue release. Tibiofemoral joint gaps for 41 patients (10 males and 31 females) in full extension and at 90 degrees of flexion both before and after the resections of both the anterior cruciate ligament (ACL) and PCL were assessed using a ligament tensioner device. The statistical analyze was performed using the Mann-Whitney U test. The results showed that medial gap in extension and flexion were 6.7 ± 1.0 and 7.3 ± 0.9 mm, and lateral gap in extension and flexion were 7.6 ± 1.1 and 8.4 ± 1.6 mm, respectively. Thus, physiological tibiofemoral gaps just after knee arthrotomy were trapezoidal and asymmetric shape with the significantly wider gaps in lateral and flexion, compared with the medial and extension, respectively ( < 0.05). However, the increases of the gaps with the ACL and PCL resections were less than 1 mm under the existence of medial soft tissues. As the medial collateral ligament is the primary restraint for the valgus instability, it was also considered to prevent the increase of the flexion gap although the PCL-which is the secondary restraint for the valgus instability-was resected. This finding is critically important for orthopedic surgeons applying PS-TKA implants, particularly for preserving soft tissues to achieve natural knee kinematics postoperatively.
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http://dx.doi.org/10.1055/s-0040-1713810DOI Listing
July 2020

Effect of Medial Osteophyte Removal on Correction of Varus Deformity in Total Knee Arthroplasty.

J Nippon Med Sch 2020 Sep 31;87(4):215-219. Epub 2020 Jan 31.

Department of Orthopaedic Surgery, Nippon Medical School.

Background: To restore neutral limb alignment in total knee arthroplasty (TKA), the procedure usually starts with removing osteophytes in varus osteoarthritic knees. However, the exact effect on alignment correction is unknown. The purpose of this study was to determine the effect of osteophyte removal alone during TKA for varus knees on correction of limb alignment on the coronal plane.

Methods: Fifteen knees with medial osteoarthritis and varus malalignment scheduled for TKA were studied. After registration in a navigation system, each knee was tested at maximum extension, and at 30, 40, and 60 degrees of flexion, before and after osteophyte removal. External loads of 10 N·m valgus torque at each angle and in both states were applied. Later, the widths of the resected osteophytes were measured.

Results: The average preoperative hip-knee-ankle angle was -14.2 degrees. The average width of osteophytes was 7.6 mm in the femur and 5.3 mm in the tibia. Angle corrections after osteophyte removal were 3.4 degrees at maximum extension, 3.4 degrees at 30 degrees flexion, and 3.6 degrees at 60 degrees flexion; the difference was significant for all angles. There was a positive correlation between osteophyte width and the degree of angle correction at 30 degrees.

Conclusion: At 30 degrees of knee flexion, osteophyte width was correlated with the degree of angle correction on the coronal plane in TKA. The degree of angle correction per 1 mm of width of removed osteophytes was 0.4 degrees.
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http://dx.doi.org/10.1272/jnms.JNMS.2020_87-503DOI Listing
September 2020

Influence of Total Knee Arthroplasty on Hip Rotational Range of Motion.

J Nippon Med Sch 2020 Sep 27;87(4):191-196. Epub 2019 Dec 27.

Department of Orthopaedic Surgery, Nippon Medical School.

Background: Total knee arthroplasty (TKA) aims to correct the rotation, as well as the alignment and articulation, of the osteoarthritic knee. We hypothesized that, in addition to improving knee kinematics, TKA affects hip rotational movement. The objective of this study was to evaluate variation in lower extremity alignment and hip rotational range of motion (ROM) after TKA.

Methods: A total of 47 patients (53 knees) with primary varus knee osteoarthritis who were scheduled for primary TKA at our center were enrolled. Hip rotational ROM was measured with the patient in supine position with 90° flexion of the hip and knee before and 3 weeks after TKA. Plain radiography and computed tomography were used to compare variations in tibial axis alignment and femoral axis alignment after bone resection, which was defined as changes in the joint lines of the distal femur and the proximal tibia.

Results: Average internal ROM, and the sum of internal and external hip rotational ROM, increased significantly; however, external hip rotational ROM did not significantly differ after TKA. Imaging findings showed that the axis of the lower leg externally rotated by 2.5°, with a 4° internal rotation of the distal femur and a 6.5° correction of the varus deformity.

Conclusion: TKA changed the neutral position of hip rotational movement and increased hip rotational ROM.
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http://dx.doi.org/10.1272/jnms.JNMS.2020_87-401DOI Listing
September 2020

Benefits of bone graft augmentation to arthroscopic Bankart repair for recurrent anterior shoulder instability with glenoid bone loss.

Knee Surg Sports Traumatol Arthrosc 2020 Jul 30;28(7):2325-2333. Epub 2019 Oct 30.

Department of Orthopaedic Surgery, Nippon Medical School, 1-1-5, Sendagi, Bunkyo-ku, Tokyo, Japan.

Purpose: Glenoid bone loss contributes to recurrent instability after arthroscopic Bankart repair alone. With significant glenoid bone loss, better results have been reported after arthroscopic Bankart repair with glenoid arc reconstruction. However, no reports compare augmentation using bone graft with non-augmentation for glenoid bone loss. The purpose of this study was to assess clinical results of an arthroscopic Bankart repair with or without arthroscopic bone graft augmentation. It was hypothesized that such bone graft augmentation would restore shoulder stability, and lead to excellent outcomes.

Methods: Of 552 patients treated for anterior glenohumeral instability with arthroscopic Bankart repair, 68 met this study's inclusion criteria of glenoid bone loss over 20% and follow-up of at least 2 years. Patients were divided into 2 groups based on whether with bone graft augmentation for glenoid bone loss [Group A: n = 35, median age; 21 years (range 13-72 years)], or not (Group B: n = 33, median age; 21 years (range 13-50 years)]. For grafting, either autologous iliac bone or artificial bone made of hydroxyapatite was used. Rowe score, recurrence rate, and return to sport were used to assess the results.

Results: Mean Rowe score was 95.0 (SD 10.6) in Group A and 69.7 (SD 27.2) in Group B (p < 0.05). The recurrence rate was 2.9% (1/36) in Group A and 48.5% (16/33) in Group B (p < 0.05). Regarding contact/collision athletes, 24 were contained in Group A and 22 in Group B. Of the patients with recurrence in Group B, 13 (59.1%) were contact/collision athletes. Finally, 50% of the contact/collision sports athletes for both groups returned to their sports at the same as pre-injury level. Of the 11 patients who returned to the same level of contact/collision sports in Group B, seven returned with residual instability. Nine athletes in Group A and 3 in Group B quit their sports for personal or social reasons.

Conclusions: Bone graft augmentation was beneficial when used with Arthroscopic Bankart repair for recurrent anterior shoulder instability with glenoid bone loss. Especially, for recurrent anterior shoulder instability with glenoid bone loss in contact/collision sports athletes, bone graft augmentation should be strongly considered as beneficial.

Level Of Evidence: Level IV.
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http://dx.doi.org/10.1007/s00167-019-05746-2DOI Listing
July 2020

Knee-Hip-Spine Syndrome: Improvement in Preoperative Abnormal Posture following Total Knee Arthroplasty.

Adv Orthop 2019 1;2019:8484938. Epub 2019 Jul 1.

Department of Orthopaedic Surgery, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo 113-8603, Japan.

An ergonomic upright body posture is maintained by the alignment of the spine, pelvis, and lower extremities, and the muscle strength of body trunk and lower extremities. The posture varies with age because of the degenerative changes in the involved structures and the weakening of the muscles. The compensatory mechanisms underlying these changes have recently been evaluated, and the loss of lumbar lordosis results in spinal kyphosis, pelvic retroversion, hip extension, knee flexion, and ankle dorsiflexion. These mechanisms are referred to as the hip-spine and knee-spine syndromes. The spine, hip, and knee are anatomically connected, and the pain and discomfort of the lower back, hip, and knee frequently arise due to degenerative changes of these structures. Thus, these mechanisms are considered as the knee-hip-spine syndrome. Spinal fusion, total hip arthroplasty, and total knee arthroplasty are the surgical procedures for severe degeneration, and their clinical outcomes for the affected sites are promising. However, despite surgeries, other structures may degenerate and result in complications, such as proximal junctional kyphosis and hip dislocation, following spinal fusion. Therefore, it is necessary to evaluate each patient under specific conditions and to treat each section while considering associations between the target structure and entire body. The purpose of this article is to introduce postural maintenance, variations with age, and improvements with surgical interventions of spine, hip, and knee as the knee-hip-spine syndrome.
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http://dx.doi.org/10.1155/2019/8484938DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6634073PMC
July 2019

Posterior tibial slope angle is associated with flexion-type Salter-Harris II and Watson-Jones type IV fractures of the proximal tibia.

Knee Surg Sports Traumatol Arthrosc 2019 Sep 10;27(9):2994-3000. Epub 2018 Dec 10.

Department of Orthopaedic Surgery, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo, 113-8603, Japan.

Purpose: Flexion-type Salter-Harris (SH) II fractures of the proximal tibia, also described as Watson-Jones (WJ) IV fractures, are rare injuries reported among adolescent athletes who are close to skeletal maturity and remain elusive. Due to this classification disagreement, the various treatments range from nonoperative to operative types, and no previous studies have explained the mechanisms of injury or the source of the fracture forces. This retrospective matched case-control study aimed to identify radiological factors that are associated with the fracture forces and to elucidate the mechanisms of these injuries.

Methods: Sixteen flexion-type SH II/WJ IV fractures of the proximal tibia in 12 adolescents (12 males, mean age of 14.6 years) were retrospectively reviewed, and knee alignment on plain radiographs was assessed to compare the radiological outcomes of the operated knees (n = 7), nonoperated knees (n = 9), and uninjured contralateral knees (n = 8). The results were compared to healthy age- and sex-matched control subjects (n = 24 knees).

Results: With regard to the radiological outcomes, the posterior tibial slope angle (PTSA) was significantly greater in the nonoperated knees (19.0° ± 1.6°), operated knees (16.8° ± 1.3°), and uninjured knees (13.6° ± 1.3°) than in the healthy knees of the matched control subjects (9.6° ± 0.4°). The anatomical tibiofemoral angle was significantly less in the nonoperated knees (0.7° ± 0.6°) than in the healthy knees of the matched control subjects (3.7° ± 0.4°).

Conclusions: These findings suggest a relationship between an increased PTSA and flexion-type SH II/WJ IV fractures of the proximal tibia, considering the deteriorating effects of an increased PTSA on knee kinematics. Adolescent active athletes with an increased PTSA and partially closed epiphysis of the proximal tibia are at risk for suffering from flexion-type SH II/WJ IV fractures of the proximal tibia until the closure of the proximal tibial epiphysis.

Level Of Evidence: Case-control study, Level III.
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http://dx.doi.org/10.1007/s00167-018-5319-2DOI Listing
September 2019

A computed-tomography-scan-based template to place the femoral component in accurate rotation with respect to the surgical epicondylar axis in total knee arthroplasty.

Knee 2018 Jan 9;25(1):195-202. Epub 2018 Jan 9.

Department of Orthopaedic Surgery, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo 113-8603, Japan.

Background: Femoral rotational alignment is considered an essential factor for total knee arthroplasty because malrotation of femoral components results in poor outcomes. To obtain proper alignment, we developed a superimposable computed tomography (CT) scan-based template to intraoperatively determine the accurate surgical epicondylar axis (SEA), and evaluated the effectiveness of this CT template.

Methods: In the experimental group (n=55), three serial slices of CT images, including medial and lateral epicondyles, were merged into a single image, and SEA was overlaid. SEA was traced onto an image of an assumed distal femoral resection level; this combined image was then printed out onto a transparent film as a CT template. Following a distal femoral resection in TKA, SEA was duplicated onto the femoral surface. Thereafter, the posterior condyle was resected parallel to this SEA. In the control group (n=53), posterior condyles were resected at three degrees of the external rotation from the posterior condylar line (PCL). A posterior condylar angle (PCA) between PCL of the femoral component and SEA was postoperatively evaluated. Positive values indicated external rotation of the femoral component from the SEA.

Results: In the experimental group, PCA was 0.01°±1.61°, and three cases were considered as outliers (greater than three degrees or less than -3 degrees). Conversely, in the control group, PCA was 0.10°±2.4°, and 12 cases were considered as outliers. Consequently, dispersion of PCA data was significantly smaller in the experimental group (P=0.004).

Conclusions: The CT template accurately determined intraoperative SEA.
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http://dx.doi.org/10.1016/j.knee.2017.11.009DOI Listing
January 2018

Midterm Result of Arthroscopic Bicruciate Ligament Sutures for Multiligament Knee Injury in an Adolescent Patient.

J Nippon Med Sch 2017 ;84(6):301-303

Department of Orthopaedic Surgery, Nippon Medical School.

Background: Treatment of multiligament knee injuries, especially in adolescent patients, is challenging for orthopedic surgeons. Repair of collateral ligaments and reconstruction of cruciate ligaments are usually performed, however, ligament reconstruction with transphyseal or physeal-sparing techniques may lead to physeal damage and growth disturbances in skeletally immature patients. We present a case report on performing bicruciate ligament sutures arthroscopically in an adolescent patient.

Patient And Methods: The patient was a 14-year-old boy, who was diagnosed with injuries to the anterior cruciate ligament, posterior cruciate ligament, and medial collateral ligament. Single-stage arthroscopic primary suturing of the anterior and posterior cruciate ligaments and open medial collateral ligament suturing were performed 7 days after the injury.

Results And Discussion: The patient returned to routine activities, including high-level competitive sports, at 8 months post-surgery, and currently, 8.5 years after surgery, remains without complications. Suture repair was able to minimize the size of the bone tunnels and to re-establish knee stability with native tissues. Therefore, the application of sutures may be a useful option for repairing multiligament knee injuries, particularly in adolescent patients.
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http://dx.doi.org/10.1272/jnms.84.301DOI Listing
February 2018

Intercondylar fracture of the distal humerus in a 7-year-old child: A case report and a review of the literature.

Medicine (Baltimore) 2017 Feb;96(6):e6085

Department of Orthopaedic Surgery, Nippon Medical School Hospital, Tokyo, Japan.

Rationale: Intercondylar fracture of the distal humerus is an extremely rare injury in children, especially in those under 8 years of age. To our best knowledge, there have been 55 reported cases of this fracture type in children in the English literature, 12 of which involved children under 8 years of age.

Patient Concerns: We report a case of intercondylar fracture of the distal humerus in a7-year-old boy fell in a gymnasium, injuring his left elbow.

Interventions: Closed reduction was initially attempted under fluoroscopic guidance, but anatomic reduction could not be achieved because the fragments were extremely unstable and irreducible. Considering the displacement and the failure of closed reduction, ORIF through a posterior approach was performed. Open reduction and double cross-pinning across the medial and lateral condylar fragments were performed through a posterior approach.

Diagnoses: Plain radiographs showed a displaced intercondylar fracture of the distal humerus. Arthrography under general anesthesia showed a severely displaced intra-articular fracture, with rotational displacement of the lateral condyle.

Outcomes: Thirteen months after surgery, there was no functional disturbance or radiographic evidence of avascular necrosis or epiphyseal growth arrest.

Lessons: Open reduction and double cross-pinning through a posterior approach can be a reliable procedure for intercondylar fracture of the distal humerus in children.
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http://dx.doi.org/10.1097/MD.0000000000006085DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5313024PMC
February 2017

Superior Dislocation of the Patella in a Young Woman without Osteophytes: A Case Report.

J Nippon Med Sch 2016 ;83(1):24-6

Department of Orthopaedic Surgery, Nippon Medical School.

Superior dislocation of the patella without patellar ligament injury is an extremely rare condition. A review of the English-language literature found only 23 reported cases. In addition, the primary factor for dislocation in most of these cases was considered to be osteophytes in the inferior pole of the patella and the anterior surface of the femoral condyle; only 1 case had no osteophytes. We treated a 19-year-old woman who sustained a painful locking of the left knee after colliding with a friend. Plain radiography and computed tomography showed superior-lateral dislocation of the patella and an interlocking between notches in the inferior pole of the patella and the anterior surface of the femoral condyle. Closed reduction without sedation was performed without difficulty, and the patient was able to walk home without pain. After 1 week, the knee was without problems. The patient had no osteophytes in the knee and had no other common risk factors, such as patella alta, ligamentous laxity, genu recurvatum, and paralytic disorders. After a comparison with previously reported cases of superior patella dislocation, we concluded that the primary factor in the present case might have been a different condition.
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http://dx.doi.org/10.1272/jnms.83.24DOI Listing
December 2016

Influence of the Medial Knee Structures on Valgus and Rotatory Stability in Total Knee Arthroplasty.

J Arthroplasty 2016 Mar 26;31(3):688-93. Epub 2015 Sep 26.

Department of Orthopaedic Surgery, Nippon Medical School, Tokyo, Japan.

Background: Precise biomechanical knowledge of individual components of the MCL is critical for proper MCL release during TKA. This study was to define the influences of the deep MCL and the POL on valgus and rotatory stability in TKA using cadaveric knees.

Methods: This study used six fresh-frozen cadaveric knees. All TKA procedures were performed using a cruciate-retaining TKA with a CT-free navigation system. We did a sequential sectioning on each knee, S1; femoral arthroplasty only, S2; medial half tibial resection with spacer, S3; anterior cruciate ligament cut, S4; tibial arthroplasty, S5; release of the dMCL, S6; release of the POL. The navigation system monitored motion after application of 10 N-m valgus loads and 5 N-m internal and external rotation torques to the tibia at 0°, 20°, 30°, 60°, and 90° of knee flexion for each sequence.

Results: There were no significant differences in medial gaps. Internal rotation angles significantly increased after S2 at 0°, 20°, and 30°, and after S6 at 90° compared with those after S1. External rotation angles significantly increased after S3 at 0°, S4 at 60°, S5 at 0°, 30° and 90°, and after S6 at 30°, 60° compared with those after S1.

Conclusion: Significant increases of rotatory instability were seen on release of the dMCL, and then further increased after release of the POL. Surgical approach of retaining the dMCL and POL has a possibility to improve the outcome after primary TKA.
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http://dx.doi.org/10.1016/j.arth.2015.09.027DOI Listing
March 2016

Serum KL-6 elevation and possible pulmonary involvement in patients with rheumatoid arthritis treated with biological agents.

J Nippon Med Sch 2014 ;81(6):364-71

Department of Orthopaedic Surgery and Rheumatology, Nippon Medical School.

Backgrounds: Interstitial lung disease (ILD) is associated with rheumatoid arthritis (RA) itself and is also induced by biological and non-biological disease-modifying antirheumatic drugs. The glycoprotein Krebs von den Lungen-6 (KL-6) is reported to be a marker for the activity of ILD.

Objectives: To elucidate the relationship between serum KL-6 levels in patients with RA treated with biological agents and pulmonary involvement on computed tomography of the chest.

Methods: The subjects were 307 patients with RA treated with infliximab, etanercept, adalimumab, or tocilizumab. Medical records were reviewed to investigate serum KL-6 levels, disease activity, and pulmonary imaging findings.

Results: Levels of KL-6 were abnormally elevated in 25 patients (8.1%): 15 patients (11.2%) treated with infliximab, 6 patients (4.4%) treated with etanercept, and 4 patients (22.2%) treated with adalimumab, but in no patients treated with tocilizumab. However, no clinical pulmonary events developed. Computed tomography of the chest showed the start or progression of interstitial fibrotic change in 5 of 25 (20%) patients with abnormal KL-6 values. The changes in disease activity did not differ significantly between patients who showed elevated KL-6 values and those who did not.

Conclusions: Serum KL-6 levels were elevated in 8.1% of patients with RA treated with biological agents. Careful observation is necessary for these patients regarding lung fibrosis.
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http://dx.doi.org/10.1272/jnms.81.364DOI Listing
September 2015

Four-segment classification of proximal humeral fractures revisited: a multicenter study on 509 cases.

J Shoulder Elbow Surg 2009 Nov-Dec;18(6):845-50. Epub 2009 Mar 17.

Department of Orthopaedic Surgery, Dokkyo Medical University, Mibu, Japan.

Background: The 4-segment classification of Neer (1970) was revised in 2002 with the inclusion of valgus-impacted fractures. However, the range of possible fracture types covered by this classification is not clear. With the aim to clarify actual fracture patterns of the proximal humerus, a retrospective, multicenter study was conducted.

Methods: We retrospectively reviewed 509 cases for which anteroposterior and trans-scapular lateral views had been taken at the time of injury. Initially, three examiners from three facilities, independently read the radiographs of each case. In the second and third phases, for more difficult cases, consensus opinions were reached.

Results: We found that 501 (98%) of the 509 fractures had an appropriate category in the revised Neer classification. There were 185 cases (36%) of one-part fractures, followed by 156 cases (31%) of 2-part surgical neck fracture, 60 cases (12%) of 2-part greater tuberosity fracture (dislocation included), 45 cases (8.8%) of 3-part fracture involving the greater tuberosity and the surgical neck (dislocation included), 31 cases (6.1%) of 4-part fracture (dislocation included), and 17 cases (3.3%) of valgus-impacted fracture.Eight fractures (1.6%) could not be classified with the revised Neer classification. They were "3-part" fractures in terms of the number of displaced segments but had a complete anatomic neck fracture.

Conclusion: We conclude that it would be appropriate to use the revised Neer classification in clinical practice. We would emphasize that, when there are 3 displaced segments, close attention should be paid to the fracture line on the anatomic neck.

Level Of Evidence: Level 4; Diagnostic study, case series.
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http://dx.doi.org/10.1016/j.jse.2009.01.018DOI Listing
February 2010

Anterior cruciate ligament injuries among wakeboarders: a case report.

J Nippon Med Sch 2004 Feb;71(1):57-62

Department of Orthopaedic Surgery, Nippon Medical School Second Hospital, 1-396, Kosugi-cho, Nakahara-ku, Kawasaki, Kanagawa 211-8533, Japan.

No previous cases of anterior cruciate ligament (ACL) injuries sustained during wake-boarding have been reported. We report on a case involving an ACL injury sustained during wakeboarding. A 27-year-old man sustained an injury while attempting a wakeboarding maneuver(a heel-side back roll, consisting of a jump and simultaneous roll toward the heel side). He failed to complete his roll before landing, striking the water with his right shoulder foremost, then plunging underwater. When his wakeboard struck the water, his left knee was sprained by the rotational force exerted by the board. The patient was diagnosed with an isolated ACL injury and underwent arthroscopic ACL reconstructive surgery. The board used in wakeboarding is wider and subject to greater water resistance than that used in water skiing. The feet of the wakeboarder are firmly attached by binding boots to a board, laterally with respect to the direction of motion, impeding easy separation of the board from the feet in the event of a fall. Thus, wakeboarding conditions would appear to put wakeboarders at particular risk for ACL injuries. These conditions need be assessed from a medical perspective in order to devise ways to minimize the risk of such injuries.
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http://dx.doi.org/10.1272/jnms.71.57DOI Listing
February 2004