Search

Background Post-arthroscopic osteonecrosis of the knee (PAONK) is a rare condition. No studies have analyzed the relationship between the meniscus extrusion and PAONK. The purpose of this retrospective study is to test a hypothesis that the degree of the medial meniscus (MM) extrusion might be significantly greater in the knees with PAONK than in the matched control knees both before and after the meniscectomy. Methods Ten knees with PAONK were detected out of a total of 876 knees which had undergone arthroscopic partial meniscectomy of the MM. Ten matched control knees were randomly selected out of the remaining 866 knees without PAONK. The clinical data of these 20 patients were retrospectively collected from the medical records. To evaluate the location of the menisci on the joint line, Extrusion width and Inner width were defined on a coronal section of magnetic resonance imaging (MRI). The intra- and inter-rater reliability was evaluated by calculating the intra- and inter-class coefficients. Statistical comparisons between the 2 groups were made using the 3 non-parametric tests. Results Before the meniscectomy, the Extrusion width of the MM (mean 4.7 ± 1.4 mm) was significantly greater than that (3.0 ± 1.3 mm) in the Control group (P = 0.0195). In the MRI taken in a range from 3 to 50 weeks after the meniscectomy, the Extrusion width of the MM (5.9 ± 1.1 mm) in the PAONK group was significantly greater than that (3.4 ± 1.4 mm) in the Control group (P = 0.0009), and the Inner width of the MM (0.6 ± 1.7 mm) in the PAONK group was significantly less than that (3.9 ± 1.0 mm) in the Control group (P = 0.0001). Conclusion A significant relationship was found between the degree of the MM extrusion and the onset of PAONK. This study suggested that the extrusion of the MM is a potential predisposing factor for PAONK.

Objective The impact of early resumption of oral intake after cardiac surgery on hemodynamics has not been characterized. The authors examined the effects of early oral intake on the oxygen supply-demand relationship in patients undergoing on-pump cardiac surgery in an early recovery after surgery program. Design Prospective data were collected in postcardiac surgical patients in a multidisciplinary intensive care unit (ICU) during an 18-month period. Setting Single institution study. Participants Forty-three patients who underwent either mitral or aortic valve repair and were successfully liberated from ventilatory support within 10 hours after surgery. Interventions Patients were either allowed to resume oral intake on the morning of the first postoperative day or not at the discretion of the surgical team after extubation. Measurements and Main Results The oxygen supply-demand relationship was assessed continuously with cardiac index and mixed venous oxygen saturation (SvO2). Among the subjects, 22 patients were allowed to eat, and transient SvO2 decrease was noted in 13 patients. All transient SvO2 decreases occurred in the patients with early oral intake. The hemodynamic status and oxygen supply-demand relationship did not differ between the patients with and without transient SvO2 decrease. All the subjects were discharged successfully from the ICU on the first postoperative day, and the length of hospital stay was similar irrespective of SvO2 decrease after early oral intake. Conclusions Early oral intake shortly after extubation was associated with transient but significant SvO2 decrease in patients who underwent fast-track recovery after open-heart surgery. Because this phenomenon did not negatively affect the postoperative outcome, early oral intake may not be harmful.

The purpose of this description is to report an "acute oblique osteotomy and ligation" (AOOL) procedure to shorten the fibula in high tibial osteotomy (HTO). A 4-cm longitudinal skin incision is made at the lateral aspect of the leg. After the central portion of the fibula is circumferentially isolated from all the periosteal tissues, a simple osteotomy is performed at the mid-portion of the fibular diaphysis in the quasi-frontal plane, which is inclined by 25 to 30° to the long axis of the fibula. Two thin holes are created beside the osteotomy line on the lateral surface of the fibula. A polyester thread is passed through the 2 holes. After the HTO is completed, the surgeon easily reduces the displaced fibular ends using this thread. This thread is securely tied to keep the contact between the 2 osteotomized surfaces. The AOOL procedure is technically easy and safely performed. We believe that the AOOL procedure is clinically useful to shorten the fibular shaft in HTO.

Background:Remnant tissue preservation may be important in improving graft healing after anterior cruciate ligament (ACL) reconstruction, but it has yet to be established whether remnant tissue preservation improves the control of pivot-shift laxity.Hypothesis:The amount of ACL graft coverage with preserved remnant tissue improves the control of pivot-shift laxity, as qualitatively determined with an electromagnetic device.Study Design:Cohort study; Level of evidence, 3.Methods:The 3-dimensional kinematics were evaluated intraoperatively using an electromagnetic sensor system in 38 patients at the time of anatomic double-bundle ACL reconstruction with remnant tissue preservation and again at a minimum of 12 months postoperatively. The magnitude of the peak coupled anterior tibial translation (pCAT) and the maximal acceleration of posterior translation (APT) during the pivot-shift test were evaluated. The degree of graft coverage by remnant tissue was determined arthroscopically at the end of surgery, which was evaluated quantitatively using a scoring system (0-9 points). The relationship between the values during the pivot-shift test and preoperative and intraoperative factors were assessed.Results:The mean (±SD) side-to-side difference of the pCAT (ΔpCAT) was significantly ( P < .0001) improved from 14.0 ± 5.0 mm to 2.6 ± 1.1 mm. Also, the mean side-to-side difference of the APT (ΔAPT) was significantly ( P < .0001) improved from 525.6 ± 99.7 mm/s2to 32.9 ± 23.6 mm/s2. The mean initial graft coverage score was 5.3 ± 2.6. The correlation analysis demonstrated that the degree of initial graft coverage was significantly correlated with the ΔpCAT ( r = −0.517, P = .0007) and ΔAPT ( r = −0.532, P = .0005). The status of the reconstructed graft at second-look arthroscopic surgery showed no significant correlations with the degree of initial graft coverage or the results of the pivot-shift test.Conclusion:The present study demonstrated that the preservation of ACL remnant tissue in anatomic double-bundle ACL reconstruction appears to improve the control of pivot-shift laxity at a minimum of 12 months postoperatively, as measured by an electromagnetic device. This improvement was significantly affected by the degree of intraoperative graft coverage with preserved remnant tissue.

BackgroundTo perform medial open-wedge high tibial osteotomy (OWHTO), surgeons expose the medial-proximal tibia by releasing or cutting the superficial layer of the medial collateral ligament (sMCL). Biomechanically, the sMCL provides primary restraint against valgus forces. Therefore, any release of the sMCL can cause valgus instability of the knee joint. The purpose of this study was to assess valgus laxity after release of the medial structure of the knee during OWHTO.MethodsBetween 2009 and 2015, 84 consecutive patients (93 knees) who underwent OWHTO using a locking plate were enrolled in this study. All patients underwent radiological examinations before surgery, during surgery, 1 year after surgery, and after plate removal to objectively assess valgus laxity. The medial joint space (MJS) and the joint line convergence angle (JLCA) of the knee were evaluated using quantitative valgus stress radiography. Clinical evaluation was performed 2 years after surgery.ResultsThe mean functional knee score improved significantly, from 65.5 to 91.1 points (p p ConclusionValgus laxity was significantly greater after release of the sMCL. However, no significant differences were noted in valgus laxity in preoperative, 1-year postoperative periods and after plate removal. Complete release of the sMCL did not cause postoperative valgus laxity after OWHTO surgery.Trial registrationTrial registration number: No.012–0360.

Background: To date, no studies have analyzed the influence on clinical outcomes of the interval between an anterior cruciate ligament (ACL) injury and double-bundle (DB) reconstruction with hamstring tendon autografts. Hypotheses: (1) Performing ACL reconstruction sooner after an injury will reduce postoperative anterior and rotatory knee instability, (2) postoperative range of knee motion or functional results will not be affected by different intervals between injury and surgery, and (3) preoperative isokinetic peak torque of the quadriceps and hamstring muscles will be lower in patients undergoing surgery earlier, while postoperative muscle strength will not be affected by surgery timing. Study Design: Cohort study; Level of evidence, 3. Methods: This study was conducted on a total of 171 patients who had undergone anatomic DB ACL reconstruction with hamstring tendon autografts. The patients were divided into 3 groups based on the time to surgery: (1) ≤1 month after the injury (group E; n = 25), (2) between 1 and 3 months after the injury (group M; n = 72), and (3) >3 months after the injury (group D; n = 74). Patients were assessed for a minimum of 2 years after surgery. Results: Concerning postoperative anterior laxity, 1-way analysis of variance demonstrated a significant difference ( P = .0274) among the 3 groups. Anterior laxity was significantly less in group E than in group D ( P = .0206). Spearman rank correlation analysis showed a significant correlation (ρ = 0.200; P = .0327) between anterior knee laxity and time to surgery. Also, a significant correlation ( P = .0461) was found between the degree of the pivot-shift phenomenon and time to surgery. There were no significant differences in loss of knee extension or flexion among the 3 groups, nor were there any differences in the Lysholm knee score or International Knee Documentation Committee grade. Postoperatively, there were no significant differences in peak torque of the quadriceps or hamstring muscles among the 3 groups. Conclusion: Early DB reconstruction led to significantly less anterior laxity compared with delayed reconstruction. There were no significant differences in postoperative range of knee motion or functional results among the 3 time intervals between injury and surgery in this study.

The purpose of this study was to clinically and radiologically compare the utility, osteoconductivity, and absorbability of hydroxyapatite (HAp) and beta-tricalcium phosphate (TCP) spacers in medial open-wedge high tibial osteotomy (HTO). Thirty-eight patients underwent medial open-wedge HTO with a locking plate. In the first 19 knees, a HAp spacer was implanted in the opening space (HAp group). In the remaining 19 knees, a TCP spacer was implanted in the same manner (TCP group). All patients underwent clinical and radiological examinations before surgery and at 18 months after surgery. Concerning the background factors, there were no statistical differences between the two groups. Post-operatively, the knee score significantly improved in each group. Concerning the post-operative knee alignment and clinical outcome, there was no statistical difference in each parameter between the two groups. Regarding the osteoconductivity, the modified van Hemert’s score of the TCP group was significantly higher (p = 0.0009) than that of the HAp group in the most medial osteotomy zone. The absorption rate was significantly greater in the TCP group than in the HAp group (p = 0.00039). The present study demonstrated that a TCP spacer was significantly superior to a HAp spacer concerning osteoconductivity and absorbability at 18 months after medial open-wedge HTO. Retrospective comparative study, Level III.

The data available from the previously reported clinical studies remains insufficient concerning the hamstring graft preparation in double-bundle anterior cruciate ligament (ACL) reconstruction.To test the hypothesis that there are no significant differences between the semitendinosus tendon alone and the semitendinosus and gracilis tendon graft fashioning techniques concerning knee stability and clinical outcome after anatomic double-bundle ACL reconstruction.A prospective study was performed on 120 patients who underwent anatomic double-bundle ACL reconstruction according to the graft fashioning technique. The authors developed the protocol to use hamstring tendon autografts. When the harvested doubled semitendinosus tendon is thicker than 6 mm, each half of the semitendinosus tendon is doubled and used for the anteromedial (AM) and posterolateral (PL) bundle grafts (Group I). On the other hand, when the harvested semitendinosus tendon is under 6 mm in thickness, the gracilis tendon is harvested additionally. The distal half of the semitendinosus and gracilis tendons are doubled and used for the AM bundle graft, and the remaining proximal half of the semitendinosus tendon is doubled and used for the PL bundle grafts (Group II). Sixty-one patients were included in Group I, and 59 patients in Group II. The two groups were compared concerning knee stability and clinical outcome 2 years after surgery.The postoperative side-to-side anterior laxity averaged 1.3 mm in both groups, showing no statistical difference. There were also no significant differences between the two groups concerning the peak isokinetic torque of the quadriceps and the hamstrings, the Lysholm knee score, and the International Knee Documentation Committee evaluation.There were no significant differences between the two graft fashioning techniques after anatomic double-bundle ACL reconstruction concerning knee stability and postoperative outcome. The present study provided orthopedic surgeons with important information on double-bundle ACL reconstruction with hamstring tendons.Level II; prospective comparative study.

Background: In anatomic double-bundle anterior cruciate ligament (ACL) reconstruction, there are great controversies concerning the ideal graft tension protocols. The purpose of this study was to clarify differences in the effect of two graft tension protocols on the clinical outcome after anatomic double-bundle anterior cruciate ligament (ACL) reconstruction by comparing the minimum 2-year clinical results. Methods: Ninety-seven patients with unilateral anatomic double-bundle ACL reconstruction were divided into two groups. In the first 44 patients (Group I), a 40-N tension was applied to each of the two hamstring autografts at 30 degrees of knee flexion, and simultaneously fixed onto the tibia. In the remaining 53 patients (Group II), a 30-N tension was applied to each graft at 10 degrees of knee flexion, and simultaneously fixed onto the tibia. Each patient was examined 2 years after surgery. Results: There wasn't a significant difference in the background of the two groups. There was no significant difference in the postoperative anterior laxity between the two groups. The average was 1.1 mm and 0.9 mm in Groups I and II, respectively. There wasn't any differences between the two groups in Lysholm knee score, International Knee Documentation Committee (IKDC) evaluation and muscle strength. Four patients had loss of knee extension in a range of 5 degrees and 10 degrees in Group I and none of the patients in Group II exhibited any loss in knee extension; which was statistically significant (p = 0.025). Conclusion: The two initial graft tension protocols did not result in any significant differences in the Lysholm knee score and IKDC grade. However, it was noted that the 40-N tension applied to each graft at 30 degrees of knee flexion more significantly induced loss of knee extension in comparison to the 30-N tension applied to each graft at 10 degrees. From a clinical viewpoint, the loss of knee extension is one of the pathological conditions that should be absolutely avoided after ACL reconstruction. Therefore, the 30-N tension applied to each graft at 10 degrees is preferable to the other graft tension protocol.

Background: Several recent studies have reported that favorable clinical results and a high level of patient satisfaction can generally be obtained with no increased risk of complications after single-bundle anterior cruciate ligament (ACL) reconstruction performed in patients >40 years of age. However, no studies have yet clarified the age-based differences in clinical outcomes after double-bundle reconstruction. Purpose: To compare clinical outcomes after double-bundle ACL reconstruction using hamstring tendon hybrid grafts between patients in 2 different age groups: ≥40 years and Study Design: Cohort study; Level of evidence, 3. Methods: A retrospective study was conducted using 96 patients (48 men, 48 women ; mean age, 37 years) who underwent unilateral ACL reconstruction between 2008 and 2011. These patients were divided into 2 groups: group M included patients ≥40 years of age (n = 40 patients), and group Y included patients Results: Mean postoperative side-to-side differences in anterior laxity were 0.5 ± 1.9 mm and 1.2 ± 1.5 mm in groups M and Y, respectively; there was a significant difference between the 2 groups ( P = .039). There were no significant differences between the groups in Lysholm knee scores, International Knee Documentation Committee (IKDC) scores, or peak muscle torque of the hamstring. On the other hand, peak muscle torque of the quadriceps was significantly lower in group M (81%) than in group Y (89%) ( P = .025). With respect to femoral tunnel enlargement, the posterolateral tunnel in group M was significantly larger than that in group Y on anteroposterior and lateral radiographs ( P = .015 and P = .002, respectively). Conclusion: Equivalent clinical outcomes were seen between the 2 age groups after double-bundle ACL reconstruction. Postoperative anterior laxity was significantly less in older patients than in younger patients, however, older patients had significantly less quadriceps muscle strength than younger patients. Surgeons should be aware of residual muscle weakness and tunnel enlargement when performing double-bundle ACL reconstruction in older patients.

Early phase prostate cancer is usually androgen-dependent, with the androgen/androgen receptor (AR) signaling pathway playing a central role. At this stage, the cancer responds well to androgen ablation therapy, but prostate cancers eventually acquire androgen independence and more aggressive phenotypes. Several studies, however, have shown that the majority of tumors still express functional AR, which is often amplified and mutated. To determine if the AR is a plausible therapeutic target, we investigated the anti-tumor effect of small interfering RNAs targeting the AR (siAR) in the human prostate cancer cells, LNCaP and 22Rv1, which express mutated AR. In both types of cells, transfection of siAR suppressed mutated AR expression and significantly reduced cell growth. Furthermore, atelocollagen-mediated systemic siAR administration markedly inhibited the growth of 22Rv1 cells subcutaneously xenografted in castrated nude mice. These results suggest that the AR is still a key therapeutic target even in androgen-independent prostate cancer (AIPC). Silencing of AR expression in AIPC opens promising therapeutic perspectives.

Background: Clinical utility of remnant tissue preservation after single-bundle anterior cruciate ligament (ACL) reconstruction has not been established. In addition, no studies have evaluated the clinical utility of remnant preservation after anatomic double-bundle ACL reconstruction. Hypothesis: The study hypotheses were as follows: (1) Subjective and functional clinical results may be comparable between anatomic double-bundle reconstructions that preserve the remnant tissue and those that resect the remnant tissue, (2) postoperative knee stability and the second-look arthroscopic evaluation may be significantly more favorable with the remnant-preserving reconstruction, and (3) the degree of the initial graft coverage may significantly affect postoperative knee stability. Study Design: Cohort study; Level of evidence, 2. Methods: A total of 179 patients underwent anatomic double-bundle ACL reconstruction. Based on the Crain classification of ACL remnant tissue, 81 patients underwent the remnant-preserving procedure (group P) and the remaining 98 patients underwent the remnant-resecting procedure (group R). There were no differences between the 2 groups concerning all background factors, including preoperative knee instability and intraoperative tunnel positions. The patients were followed for 2 years or more. Results: The subjective and functional clinical results were comparable between the 2 reconstruction procedures. Side-to-side anterior laxity was significantly less ( P = .0277) in group P (0.9 mm) than in group R (1.5 mm). The pivot-shift test was negative in 89% of group P and 78% of group R patients; the result for group R was significantly lower ( P = .0460). In the arthroscopic observations, results for group P were significantly better than for group R concerning postoperative laceration and fibrous tissue coverage of the grafts ( P = .0479). Conclusion: Remnant preservation in anatomic double-bundle ACL reconstruction did not significantly improve subjective and functional results in the short-term evaluation, but it significantly improved postoperative knee stability. The degree of initial graft coverage significantly affected postoperative knee stability.

Heterotopic ossification (HO) occurs at a high frequency in severe orthopaedic extremity injuries; however, the etiology of traumatic HO is virtually unknown. Osteogenic progenitor cells have previously been identified within traumatized muscle. Although the signaling mechanisms that lead to this dysregulated differentiation pathway have not been identified, it is assumed that inflammation and fibrosis, which contribute to an osteoinductive environment, are necessary for the development of HO. The hypothesis of this study was that cytokines related to chronic inflammation, fibrogenesis and osteogenesis become up-regulated following severe muscle trauma where HO forms. Classification of these cytokines by their differential expression relative to control muscle will provide guidance for further study of the mechanisms leading to HO. Real-time RT-PCR analysis revealed no significant up-regulation of cytokines typically associated with HO (e.g., BMP-4, as observed in the genetic form of heterotopic ossification, Fibrodysplasia Ossificans Progressiva). Instead, the cytokine gene expression profile associated with the traumatized muscle included up-regulation of cytokines associated with osteogenesis and fibrosis (i.e., BMP-1 and TGF-beta1). Using immunohistochemistry, these cytokines were localized to fibroproliferative lesions, which have previously been implicated in HO. This study identifies other cell and tissue-level interactions in traumatized muscle that should be investigated further to better define the etiology of HO.

Few studies have been conducted to investigate biological factors that affect postoperative knee motion after total knee arthroplasty (TKA). The purpose of this study is to test the hypothesis that range of knee motion (ROM) at 4 weeks after TKA is correlated with the concentration of extracellular matrix metalloproteinase inducer (EMMPRIN) and transforming growth factor (TGF)-beta1 in the exudative fluid harvested from the joint after surgery. A prospective measurement study was conducted with 20 osteoarthritis patients who underwent TKA. At 48 h after surgery, the exudate was harvested from a closed drainage system. Enzyme-linked immunosorbent assay was performed to measure the concentration of TGF-beta1, EMMPRIN, MMP-1, 2, 9, tissue inhibitor of metalloproteinase-1, and Hyalunonan. Knee flexion angle was measured before and at 4 weeks after surgery. There was a significant correlation between the EMMPRIN levels and knee flexion angle (r = 0.557, p = 0.0148). Western blot analysis of the exudate showed a prominent band for EMMPRIN at 27 kDa. On the other hand, there was no correlation between the TGF-beta1 levels and the knee flexion angle. This study showed that EMMPRIN levels after TKA affect the postoperative ROM. As to clinical relevance, EMMPRIN in the exudate after TKA is a promising biological indicator to predict difficulty in restoring postoperative ROM.

Dry eye is a condition of dry, irritated, burning or gritty feeling in the eyes. It is mainly caused by ocular surface diseases, immunomodulation or injuries that affect tear secretion or composition.The diagnosis and treatment of dry eyes have improved dramatically during recent years. Application of artificial tears is usually carried out as a method of treatment, but it requires frequent application and provides only temporary effect. In addition, it leads to epithelial cell toxicity, changes in epithelial membrane permeability and increased chances of eye infections. Punctal occlusion prevents the discharge of natural tears from the lacrimal punctum. Punctal occlusion prolongs the duration of tears on the ocular surface of the eye and improves the symptoms of dye eye significantly. The conventional method of punctal occlusion is the application of solid-type punctal plugs such as collagen-rod, silicone or plastic plugs. Such plugs often cause an unpleasant foreign-body sensation, corneal epithelial cell damage, granulation and accidental dropout.To overcome such problems, we developed 3% atelocollagen solution, which

Background: Tunnel enlargement and coalition following double-bundle anterior cruciate ligament (ACL) reconstruction with hamstring tendon autografts has not yet been sufficiently studied. Hypothesis: The incidence and the degree of femoral tunnel enlargement will be significantly greater than those for tibial tunnel enlargement after anatomic double-bundle ACL reconstruction using hamstring tendon autografts. There will be no significant correlation between tunnel enlargement and coalition and the postoperative knee laxity. Study Design: Case series; Level of evidence, 4. Methods: Thirty-nine patients who underwent anatomic double-bundle ACL reconstruction using semitendinosus and gracilis tendon autografts were followed up for 1 year after surgery. The grafts were simultaneously fixed at 10° of knee flexion with EndoButtons and spiked staples. All patients were examined with computed tomography and the standard clinical evaluation methods at 2 weeks and 1 year after surgery. Results: The degree of tunnel enlargement of the femoral anteromedial and posterolateral tunnels averaged 10% to 11% and 7% to 9%, respectively, while that of the tibial anteromedial and posterolateral tunnels averaged 3% to 7% and 1% to 6%. The degree and incidence of the anteromedial and posterolateral tunnel enlargement were significantly greater in the femur than in the tibia ( P < .0335 and P < .0405, respectively). On the femoral and tibial intra-articular surface, tunnel outlet coalition was found in 5% and 77% of the knees, respectively, at 1 year after surgery. There was no significant correlation between tunnel enlargement and coalition and the clinical outcome. Conclusion: The incidence and the degree of each tunnel enlargement in the femur were significantly greater than that in the tibia. However, the incidence of tunnel coalition in the femur was significantly less than that in the tibia after double-bundle ACL reconstruction with a transtibial technique. There was no significant correlation between tunnel enlargement and coalition and the clinical outcome. Clinical Relevance: The present study provides orthopaedic surgeons with important information on double-bundle ACL reconstruction with hamstring tendons.