A genome-wide association study identifies a locus associated with knee extension strength in older Japanese individuals.

Sarcopenia is a common skeletal muscle disease in older people. Lower limb muscle strength is a good predictive value for sarcopenia; however, little is known about its genetic components. Here, we conducted a genome-wide association study (GWAS) for knee extension strength in a total of 3452 Japanese aged 60 years or older from two independent cohorts. We identified a significant locus, rs10749438 which is an intronic variant in TACC2 (transforming acidic coiled-coil-containing 2) (P = 4.2 × 10-8). TACC2, encoding a cytoskeleton-related protein, is highly expressed in skeletal muscle, and is reported as a target of myotonic dystrophy 1-associated splicing alterations. These suggest that changes in TACC2 expression are associated with variations in muscle strength in older people. The association was consistently observed in young and middle-aged subjects. Our findings would shed light on genetic components of lower limb muscle strength and indicate TACC2 as a potential therapeutic target for sarcopenia.

A Single Case Study Comparing High Tibial Osteotomy With Matrix-Associated Autologous Chondrocyte Implantation With Medial Collateral Ligament Release Treating Bilateral Severe Medial Knee Osteoarthritis.

CASE: A 62-year-old woman with bilateral severe medial unicompartmental knee osteoarthritis underwent right high tibial osteotomy (HTO) at the age of 49 and left matrix-associated autologous chondrocyte implantation covering with periosteum (pMACI) with medial collateral ligament (MCL) release at age 52 years. At the 13-year follow-up, she could walk and trek with good clinical scores, had high patient satisfaction, and had cartilaginous reparative tissue seen at second-look arthroscopy in her left knee. CONCLUSION: This case suggests that pMACI with MCL release might be a possible alternative to HTO in a varus knee undergoing cartilage replacement surgery when HTO is contraindicated.

Meniscal Allograft Transplantation Concomitant With Cartilage Repair for Symptomatic Lateral Meniscus-Deficient Knees With Over Two Years of Follow-up.

Background and objective The treatment for symptomatic meniscus-deficient knees with cartilage defects remains challenging on account of insufficient meniscal substitutes. One solution for this might involve combining meniscal allograft transplantation (MAT) and cartilage repair. In this study, we aimed to analyze the effectiveness and safety of MAT concomitant with cartilage repair for symptomatic lateral meniscus-deficient knees in a setting with limited availability of meniscal transplants in Japan. Methods Nine patients who underwent MAT concomitant with osteochondral transplantation (five) and/or autologous chondrocyte implantations (seven) were followed up for at least two years (mean: 51.2 months, range: 24-84 months). Their demographic data and other characteristics were as follows - mean age: 51.7 years, range: 36-67 years; men/women: 4/5; cause: trauma/discoid meniscus: 8/1; cartilage defect size: mean: 6.7 cm2/knee, range: 1.0-11.3. The effectiveness and safety were evaluated clinically by using the Lysholm Knee Scoring Scale (LKSS) and Japanese Orthopaedic Association (JOA) knee score, physical examination, X-rays, and MRI preoperatively and at one, 12, and 24 months after the implantation. Differences between the variables were analyzed using the Friedman test and Scheffe's multiple comparisons. Results The median LKSS and JOA scores significantly improved from 70 points (range: 21-80) and 35 (25-45) preoperatively to 86.5 (65-98) and 87.5 (80-95) at 24 months after surgery, respectively (p<0.001, p=0.0013). The range of motion (ROM), femorotibial angle, and the lateral joint space showed no significant changes. However, lateral meniscal extrusions (LMEs) increased by 3.0 mm (range: 0-6.3 mm) at one month postoperatively and remained unchanged until two years postoperatively. Treatment failure occurred in one case, which was revised by total knee arthroplasty (TKA) at 18 months postoperatively. Additional surgeries were needed in some cases: lateral meniscal tear (three cases), contracture (two cases), and patellar instability (one case). However, neither infection nor allergic reaction was observed in the blood exams. Conclusions Although MAT concomitant with cartilage repair showed good clinical outcomes, half of the cases needed additional surgeries. Based on our findings, this technique should be adopted only in select cases and performed by a handful of highly experienced surgeons.

Total knee arthroplasty combined with medial patellofemoral ligament augmentation using a Leeds-Keio ligament for 'Windswept deformity' with ipsilateral valgus deformity and permanent patellar dislocation: A case report and a literature review.

We present a 'Windswept deformity' in patient who had osteoarthritis with a mild varus and very severe valgus with ipsilateral permanent patellar dislocation. An 83-year-old woman could not walk for the past a few years due to bilateral knee pain. The femorotibial angle was 196° in the right knee pre-operatively and 134° in the left knee with permanent patellar dislocation. She underwent a staged total knee arthroplasty (TKA) for the right knee, and a semi-constrained TKA for the left knee with medial patellofemoral ligament (MPFL) augmentation using a Leeds-Keio (LK) ligament. At the final follow-up three years after surgery, bilateral knee pain and the extension lag had disappeared and range of motion (ROM) was 0° in extension and 130° in flexion for both knees without patellar re-dislocation. This clinical case indicates that the unconstrained and semi-constrained type of TKA combined with the MPFL augmentation using an LK ligament is effective to treat a 'Windswept deformity'.

Fibromas arising from the posterior cruciate ligament tendon sheath in the bilateral knee joints: Case report.

Fibroma of tendon sheath in the intra-knee joint is a very rare and benign soft-tissue tumour which has been reported unilaterally in the various aged people. To help distinguish it from other similar kinds of lesions and symptoms including osteoarthritis, we report the oldest case of fibromas arising from the posterior cruciate ligament tendon sheath in the bilateral knee joints within one year of each other confirmed with magnetic resonance imaging (MRI) features, operative findings and histological examination.

Osteomyelitis of the accessory and body of the navicular bone: a case report.

A 16-year-old boy developed left foot pain of unknown cause that was unresponsive to conservative treatment, associated with fever and difficulty walking. He was admitted to our hospital with osteomyelitis of the accessory and body of the navicular bone. Surgery could not be performed because the patient had been diagnosed with Wiskott-Aldrich syndrome. After antibiotic therapy, laboratory abnormalities and pain had resolved. One year after treatment, the patient had returned to his original level of sports activity. Both an accessory navicular and the body of the navicular bone may develop osteomyelitis in immunocompromised patients; early diagnosis is important for prescribing effective conservative treatment.

Sporadically occurred bilateral osteochondritis dissecans on the trochlea of the femur: case report.

We report the case of a 13-year-old boy with bilateral osteochondritis dissecans in the lateral femoral trochlea of the knees. They were classified as grade 4 in the right knee and grade 1 in the left knee on the basis of the Nelson classification within 1 year after first consultation. In the right knee, the fragment was surgically fixed, but the left knee healed with conservative treatment. This case indicates the possibility that osteochondritis dissecans of the lateral femoral trochlea may develop bilaterally at different times and present at different stages. The case shows the importance of early diagnosis and appropriate treatment on the basis of the stage.

Longitudinal Change of Medial and Lateral Patellar Stiffness After Reconstruction of the Medial Patellofemoral Ligament for Patients with Recurrent Patellar Dislocation.

BACKGROUND: Longitudinal changes in patellar stiffness following reconstruction of the medial patellofemoral ligament for recurrent patellar dislocation at full extension are unknown. METHODS: Fifteen consecutive patients (three men and twelve women, with a mean age of twenty-two years) with seventeen knees were matched by sex and age to thirty-two reference subjects in this prospective study. The follow-up period was a minimum of twenty-four months. The medial patellofemoral ligament reconstruction used an autograft semitendinosus tendon and an interference screw system with or without lateral release under 10 N of laterally directed force. The medial patellar stiffness and lateral patellar stiffness were measured in 0° of knee extension using the Patella Stability Tester preoperatively; postoperatively at three, six, twelve, and eighteen months; and at the time of the latest follow-up. Before and after the surgical procedure, patients were evaluated for apprehension and Kujala and Lysholm scores; radiographic examinations were performed to evaluate changes, including osteoarthritic changes. RESULTS: The medial stiffness of the affected side before the surgical procedure was significantly lower than the lateral stiffness (p = 0.004) and the stiffness for healthy reference knees (p = 0.004). Medial stiffness three months after the surgical procedure was significantly elevated compared with lateral values (p = 0.027), preoperative values (p < 0.001), and reference group values (p = 0.002); reached the reference level by six months; and was maintained for up to two years. Furthermore, medial stiffness and lateral stiffness were well balanced after six months and this balance was sustained for up to two years postoperatively. No recurrent dislocation occurred during the follow-up period; one patient experienced apprehension. Postoperative radiographic findings and clinical scores were significantly improved at the time of the latest follow-up (p < 0.05). One knee progressed to patellofemoral osteoarthritis. CONCLUSIONS: The value for medial stiffness was significantly improved three months after medial patellofemoral ligament reconstruction compared with the preoperative and lateral values and returned to the reference level by six months. Medial stiffness and lateral stiffness of the patella were well balanced by six months and retained that balance for up to two years, with good clinical results. LEVEL OF EVIDENCE: Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.

Simultaneous anterior cruciate ligament reconstruction and dome-shaped high tibial osteotomy for severe medial compartment osteoarthritis of the knee.

BACKGROUND: The optimal surgical procedure to address both anterior cruciate ligament (ACL) deficiency and medial compartment osteoarthritis (OA) has been controversial. CASE REPORT: A 49-year-old woman with a 30-year history of chronic anterior cruciate ligament (ACL) deficiency, medial compartment osteoarthritis, and varus deformity presented with medial knee pain and apprehension with walking and playing soccer. Her preoperative range of motion was from 0° of extension to 135° of flexion. The anterior drawer sign (1+), Lachman test (1+), and pivot shift test (glide) were positive before surgery, as measured by the International Knee Documentation Committee knee examination form. The patient underwent simultaneous arthroscopic ACL single-socket and single-bundle reconstruction using hamstring tendons, dome-shaped high tibial osteotomy using the TomoFix fixation device, and mosaicplasty to the medial condyle. The standing femorotibial angle changed from 185° preoperatively to 172° postoperatively. Range of motion exercises were started 1 week after surgery, and partial weight bearing was allowed 2 weeks after surgery. The patient returned to her baseline physical level 2 years after the operation. Range of motion was -10° of extension and 130° of flexion, and the anterior drawer sign, Lachman test, and pivot shift test were all negative at the final 3-year follow-up. CONCLUSION: An ACL reconstruction combined with a dome-shaped high tibial osteotomy using a locking plate is one option for treating an aged athlete with ACL deficiency and severe medial compartment osteoarthritis, and can allow the athlete to return to sports activity.

Quantitative analysis of glycosaminoglycans, chondroitin/dermatan sulfate, hyaluronic acid, heparan sulfate, and keratan sulfate by liquid chromatography-electrospray ionization-tandem mass spectrometry.

We developed a method using liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) with a selected reaction monitoring (SRM) mode for simultaneous quantitative analysis of glycosaminoglycans (GAGs). Using one-shot analysis with our MS/MS method, we demonstrated the simultaneous quantification of a total of 23 variously sulfated disaccharides of four GAG classes (8 chondroitin/dermatan sulfates, 1 hyaluronic acid, 12 heparan sulfates, and 2 keratan sulfates) with a sensitivity of less than 0.5 pmol within 20 min. We showed the differences in the composition of GAG classes and the sulfation patterns between porcine articular cartilage and yellow ligament. In addition to the internal disaccharides described above, some saccharides derived from the nonreducing terminal were detected simultaneously. The simultaneous quantification of both internal and nonreducing terminal saccharides could be useful to estimate the chain length of GAGs. This method would help to establish comprehensive "GAGomic" analysis of biological tissues.

Usefulness of braided polyblend polyethylene suture material for flexor tendon repair in zone II by the side-locking loop technique.

Flexor tendon injuries in zone II were treated in 14 fingers of 13 patients with our method. Firstly, a 2-strand core suture was made by the side-locking loop technique using a USP 2-0-sized braided polyblend polyethylene suture, then 7-strand peripheral cross-stitches were added using a USP 5-0-sized monofilament nylon suture. Post-operative exercises included passive flexion and extension without external fixation on the next day of surgery. Average follow-up observation period was 18 months. As results, the Strickland method of assessment for surgical outcome showed excellent in eight digits and good in five digits, though there was a poor outcome in one digit. Our suture method enabled early post-operative mobilisation exercise without using a splint, while preventing adhesion between the repaired tendon and peripheral tissues, which is considered to provide far greater ultimate tensile strength and a smaller gap at the sutured site than by the conventional method.

Clinical outcomes of revision meniscal repair: a case series.

BACKGROUND: Meniscal preservation results in better clinical outcomes than meniscectomy; however, no studies have evaluated the results of revision meniscal repair. HYPOTHESIS: Revision meniscal repair can achieve good clinical outcomes. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: The study participants were 16 patients with symptomatic meniscal retears of a total of 96 patients who underwent primary arthroscopic meniscal repair. Fifteen of these 16 patients underwent revision meniscal repair. The mean age at revision was 27 years, and the mean duration between the primary operation and revision was 27 months. Eight patients had degenerative changes of the meniscus at revision. Clinical outcomes were assessed using the Lysholm score and the Tegner sports activity score, and image assessment was performed using magnetic resonance imaging. RESULTS: Five patients had re-retears of a resutured meniscus, and the mean duration between revision and the re-retear was 25 months (range, 8-68 months). The mean follow-up of patients without re-retears was 41 months (range, 24-74 months), and the mean Lysholm score in those without re-retears significantly improved from 81.4 points (range, 73-89 points) at pre-revision to 97.4 points (range, 90-100 points) at the final survey (P = .0001). Degenerative changes of the meniscus at the revision site were observed in all 5 patients with re-retears but in only 3 of the 10 patients without re-retears. CONCLUSION: Revision meniscal repair should be considered in the setting of a retorn meniscus without degenerative changes.

A comparison of patient-reported outcomes and arthroscopic findings between drilling and autologous osteochondral grafting for the treatment of articular cartilage defects combined with anterior cruciate ligament injury.

BACKGROUND: To compare the patient-reported outcomes and arthroscopic findings between drilling and autologous osteochondral grafting (AOG) for the treatment of articular cartilage defects combined with anterior cruciate ligament (ACL) injuries. METHODS: The subjects were 40 patients who had articular cartilage defects in the weight-bearing part of the medial and lateral femur condyle combined with ACL injuries that were treated by drilling (20 patients) or AOG (20 patients) at the same time as ACL reconstruction was performed. In the drilling group patients, lesions were penetrated with multiple 1.2-mm Kirschner wires, and in the AOG group patients, grafts were made to cartilage defects from one to three osteochondral pegs harvested from the less-weight-bearing periphery of the articular surface of the femoral condyle. The patient-reported outcomes were assessed using the International Knee Documentation Committee (IKDC) subjective knee examination score. Second-look arthroscopy was performed to evaluate the repaired cartilage macroscopically. RESULTS: The median follow-up duration was 25 (range, 12-42) months. The IKDC scores were significantly improved from 64.4 to 95.4 points in the drilling group and from 52.3 to 94.3 points in the AOG group, with no difference between the two groups, although there was a difference in the repaired cartilage findings of arthroscopy. CONCLUSION: In this study, no differences in IKDC scores were found in patients with a concomitant ACL rupture and an osteochondral lesion treated by drilling or AOG at a minimum follow-up of 1year, regardless of the differences at arthroscopic grading of the ICRS classification. LEVEL OF EVIDENCE: Case-control study (LEVEL III).

A "sandwich" method of reconstruction of the medial patellofemoral ligament using a titanium interference screw for patellar instability in skeletally immature patients.

BACKGROUND: No standard surgical procedure for medial patellofemoral ligament (MPFL) reconstruction exists in skeletally immature patients with patellar instability. This study aimed to evaluate the clinical effectiveness of a novel reconstruction technique for the MPFL in patients with patellar instability because of non-closure of the epiphyseal line. METHODS: The "sandwich" method was fixation of the patella between a double-stranded semitendinosus tendon through the posterior third of the femoral insertion of the medial collateral ligament (MCL) as a pulley with a titanium interference screw in a single patellar tunnel. Five knees in five patients were studied: four with recurrent and one with habitual patellar dislocations. Subjects underwent MPFL reconstruction with or without lateral release. Patients were evaluated using pre-operative and post-operative physical and radiographic examinations, including apprehension testing, assessment of tilting and congruence angles, medial and lateral shift ratios under stress measured using X-ray imaging, and Kujala and Lysholm scores. RESULTS: No patient experienced recurrent post-operative episodes of dislocation or subluxation. By the final follow-up, patellar apprehension had disappeared in all patients. In addition, all patients showed significant improvement in the following: tilting angle, congruence angle, lateral shift ratio, Kujala score, and Lysholm score. CONCLUSIONS: The MPFL reconstruction methods, using a double-stranded semitendinosus autograft and sparing the femoral physeal line in non-closure of the epiphyseal line, provide acceptable short-term results for the treatment of patellar instability.

Evaluation of magnetic resonance imaging and clinical outcome after tissue-engineered cartilage implantation: prospective 6-year follow-up study.

BACKGROUND: Autologous chondrocyte implantation (ACI) is an important procedure when repairing cartilage defects of the knee. We previously reported several basic studies on tissue-engineered cartilage, and conducted a multicenter clinical study in 2009. In this clinical study, we evaluated the patients' clinical scores and MRI findings before and after tissue-engineered cartilage implantation, and compared the data obtained at 1 year and approximately 6 years post-implantation. METHODS: Fourteen patients who underwent implantation of tissue-engineered cartilage to repair cartilage defects of the knee were evaluated. Tissue-engineered cartilage was produced by culturing autologous chondrocytes three dimensionally in atelocollagen gel. The patients were evaluated clinically using the Lysholm score, and the original knee-function score at pre-implantation and at 1 year and approximately 6 years post-implantation. MRI scans were obtained at the same observation periods. A modified magnetic resonance observation of cartilage repair tissue (MOCART) system was used to quantify clinical efficacy based on the MRI findings. RESULTS: In approximately 6 years of follow-up, none of the 14 patients reported any subjective symptoms of concern. The mean Lysholm score and the original knee-function score (63.0 ± 10.1, 59.9 ± 5.7) significantly improved at 1 year after implantation (86.4 ± 11.8, 94.1 ± 9.2), and were maintained until 6 years after implantation (89.8 ± 6.2, 89.9 ± 11.2), although some patients showed deterioration of Lysholm and original knee scores between 1 year post-implantation and the final follow-up. The mean MOCART score was 13.2 ± 12.0 pre-implantation, and 62.5 ± 24.7 at 1 year and 70.7 ± 22.7 at approximately 6 years post-implantation. The MOCART scores at 1 year and 6 years were significantly higher than the pre-implantation score, but there was no significant difference between the scores at 1 and 6 years, indicating that the MRI results at 1 year after implantation were maintained for the next 5 years. CONCLUSIONS: The clinical scores and MRI findings after implantation of tissue-engineered cartilage were improved at 1 year after implantation and were maintained until 6 years after implantation.

Sequential multiple insufficiency fractures around knee over 6 months in a patient with primary osteoporosis.

In this report, we describe a case of multiple insufficiency fractures occurring over 6 months in the bilateral knees of an individual with primary osteoporosis. An 87-year-old woman complained of spontaneous pain in her right knee. A plain X-ray did not show any lesions at the time; however, 2 weeks later, a slightly displaced supracondylar fracture was observed. The fracture was treated with a long leg cast for 6 weeks. The patient was able to walk with a walker 12 weeks after the injury, but her right thigh muscles had atrophied. Four months after the first injury, she suffered left knee pain. Magnetic resonance imaging (MRI) showed an undisplaced supracondylar fracture of the left femur. After undergoing the same treatment as for the previous fracture for 8 weeks, she complained of pain in the proximal tibia, and a fracture in the lateral tibial plateau was observed by MRI. No malignancy or endocrine disorders were found by imaging or laboratory studies. Her bone mineral density was found to be low, and she was diagnosed with multiple insufficiency fractures due to primary osteoporosis. The work overload on the healthy side induced by muscle weakness on the affected side may have caused the subsequent insufficiency fractures on the healthy side. These findings suggest that one should pay attention to and treat lower limb muscle atrophy when managing insufficiency fractures of the lower limbs.

Effectiveness and limitations of autologous osteochondral grafting for the treatment of articular cartilage defects in the knee.

PURPOSE: To evaluate the effectiveness and limitations of autologous osteochondral grafting for the treatment of articular cartilage defects in the knee. METHODS: The subjects were 40 patients who had undergone autologous osteochondral grafting. Fifteen knees had cartilage defects combined with anterior cruciate ligament tears (ACL group), 15 knees had cartilage defects combined with osteoarthritis (OA group), and 10 knees had cartilage defects combined with osteochondral dissecans (OCD group). From one to five osteochondral pegs were harvested from the less-weight-bearing periphery of the articular surface of the femoral condyle and grafted to cartilage defects. The clinical results were assessed based on the Lysholm score and radiographic and magnetic resonance imaging (MRI) image assessment. RESULTS: The median follow-up duration was 24 months (range from 12 to 41 months). The mean Lysholm score following treatment was improved in all groups. The patients who had cartilage defects combined with OA had a significantly poorer prognosis than did those with cartilage defects combined with ACL or OCD. In the OA group, advanced stage and an alignment abnormality were correlated with poor prognosis. Advanced age was correlated with poor prognosis. Other parameters showed no significant difference in prognosis. CONCLUSION: Autologous osteochondral grafting was found to be an effective technique for treating relatively young patients who had cartilage defects combined with ACL injury or OCD, but this technique showed limited results in treating cartilage defects based on advanced patient age and degenerative changes in the cartilage. LEVEL OF EVIDENCE: Diagnostic studies-investigating a diagnostic test, Level III.

Correlation of changes in pain intensity with synovial fluid adenosine triphosphate levels after treatment of patients with osteoarthritis of the knee with high-molecular-weight hyaluronic acid.

We sought to determine whether a clinical association exists between osteoarthritis (OA)-associated knee pain and adenosine triphosphate (ATP) levels in synovial fluid (SF). A total of 28 patients with 28 primary OA knees were included. They routinely received intra-articular injection of high-molecular-weight hyaluronic acid (HA) once weekly for 5 weeks (treated group). Eight patients without knee pain who had undergone an operation for anterior or posterior cruciate ligament reconstruction 2 years ago were also examined (control group). SF and blood ATP concentrations, total amount of ATP, total SF volume, and Visual Analogue Scale (VAS) scores in all patients were measured and we compared pre-treatment values with those 1 week after the final treatment. We evaluated the correlation of change in total ATP (ΔATP) and change in VAS score (ΔVAS), ΔVAS and change in SF volume (ΔSF), and ATP concentration in SF and blood. In the treated group, SF ATP concentration, total amount of ATP, SF volume, and VAS score were all significantly lower post-treatment than pre-treatment (p = 0.0005, 0.0003, 0.0022, and < 0.0001, respectively). In treated group, ΔVAS was significantly associated with ΔATP (r = 0.56, p = 0.0032), ΔSF was significantly associated with ΔVAS (r = 0.78, p < 0.0001), and total amount of SF ATP and SF volume at pre-treatment were significantly higher than the control group (p < 0.0001, p < 0.0001) We demonstrated an association between SF ATP level changes and OA knee pain, which should facilitate a further understanding of OA pain mechanisms.