Comparison of early clinical outcome in carpal tunnel release - mini-open technique with palmar incision vs. endoscopic technique with wrist crease incision.

BACKGROUND: The purpose of this study was to examine two techniques for Carpal Tunnel Syndrome, mini-Open Carpal Tunnel Release (mini-OCTR) and Endoscopic Carpal Tunnel Release (ECTR), to compare their therapeutic efficacy. METHODS: Sixteen patients who underwent mini-OCTR in palmar incision and 17 patients who underwent ECTR in the wrist crease incision were included in the study. All patients presented preoperatively and at 1, 3, and 6 months postoperatively and were assessed with the Visual Analogue Scale (VAS) and the Disabilities of Arm, Shoulder and Hand Score (DASH). We also assessed the pain and cosmetic VAS of the entire affected hand or surgical wound, and the patient's satisfaction with the surgery. RESULTS: In the objective evaluation, both surgical techniques showed improvement at 6 months postoperatively. The DASH score was significantly lower in the ECTR group (average = 3 months: 13.6, 6 months: 11.9) than in the mini-OCTR group (average = 3 months: 27.3, 6 months: 20.6) at 3 and 6 months postoperatively. Also, the pain VAS score was significantly lower in the ECTR group (average = 17.1) than in the mini-OCTR group (average = 36.6) at 3 months postoperatively. The cosmetic VAS was significantly lower in the ECTR group (average = 1 month: 15.3, 3 months: 12.2, 6 months: 5.41) than in the mini-OCTR group (average = 1 month: 33.3, 3 months: 31.2, 6 months: 24.8) at all time points postoperatively. Patient satisfaction scores tended to be higher in the ECTR group (average = 3.3) compared to the mini-OCTR group (average = 2.7). CONCLUSIONS: ECTR in wrist increase incision resulted in better pain and cosmetic recovery in an early postoperative phase compared with mini-OCTR in palmar incision. Our findings suggest that ECTR is an effective technique for patient satisfaction.

Fracture Line Distributions of Undisplaced Distal Radius Fractures in Relation to Rupture of the Extensor Pollicis Longus Tendon.

Rupture of the extensor pollicis longus (EPL) tendon is a known complication after undisplaced distal radius fracture (DRF). However, no report has revealed the relationship between EPL tendon rupture and the fracture pattern. Thus, this study aimed to investigate the characteristics of fractures at risk of EPL tendon rupture using fracture line mapping of undisplaced DRFs. This study used computed tomography imaging data of undisplaced DRFs with (n=18) and without EPL tendon rupture (n=52). Fracture lines obtained from 3D reconstruction data were drawn manually after matching with a 2D template wrist model. Fracture maps represented the fracture line distribution by superimposing the fracture lines of all 70 patients. Heat maps showed the relative frequency of the fracture lines as a gradual color change. Fracture lines of cases with EPL tendon rupture were concentrated in the proximal border of Lister's tubercle. By contrast, fracture lines of cases without EPL tendon rupture were relatively dispersed.

Relationship between clinical outcomes and nerve conduction studies before and after surgery in patients with carpal tunnel syndrome.

BACKGROUND: Nerve conduction study (NCS) is the only useful test for objective assessment of carpal tunnel syndrome (CTS). However, the relationship between pre- and postoperative NCS and clinical outcomes was unclear. This study aimed to determine whether pre- and postoperative (6 months) NCS could predict patient-oriented and motor outcomes (6 and 12 months postoperatively) in patients with CTS. METHOD: Of the 85 patients with CTS, 107 hands were analyzed from March 2011 to March 2020. All patients underwent open carpal tunnel release and were examined using the disabilities of the arm, shoulder and hand (DASH) questionnaire and grip strength (GS) preoperatively and 6 and 12 months postoperatively. Moreover, NCS was examined preoperatively and 6 months postoperatively. Distal motor latency (DML) and sensory conduction velocity (SCV) were the parameters used for NCS. The correlation coefficient between NCS and DASH or GS was calculated. A receiver operating characteristic curve was utilized to determine the NCS threshold value to predict DASH and GS improvement. RESULTS: The average scores of GS preoperatively and 6 and 12 months postoperatively were 21.3, 22.3, and 22.8, respectively. On the other hand, the average scores of DASH preoperatively and 6 and 12 months postoperatively were 28.8, 18.3, and 12.2, respectively. The average NCS scores (DML and SCV) preoperatively/6 months postoperatively were 7.3/5.4 and 27.8/36.7, respectively. Preoperative NCS did not correlate with DASH and GS. Postoperative SCV correlated with the change in grip strength (6-12 months, r = 0.67; 0-12 months, r = 0.60) and DASH (0-12 months, r = 0.77). Moreover, postoperative DML correlated with the change in DASH (6-12 months, r = - 0.33; 0-12 months, r = - 0.59). The prediction for the improvement of GS/DASH achieved a sensitivity of 50.0%/66.7% and a specificity of 100%/100%, at an SCV cutoff score of 38.5/45.0 or above. The prediction for improvement of GS/DASH achieved a sensitivity of 83.3%/66.7% and a specificity of 100%/66.7% at a DML cutoff score of 4.4/4.4 or below. CONCLUSION: NCS at 6 months postoperatively can be used to predict the improvement of clinical outcome after 6 months postoperatively in patients with CTS.

Osteosynthesis for Geriatric Acetabular Fractures: An Epidemiological and Clinico-Radiological Study Related to Marginal or Roof Impaction.

This retrospective study sought to elucidate the incidence rates of roof impaction (RI) and marginal impaction (MI) and radiological and clinical outcomes of open reduction and internal fixation (ORIF) for RI and MI in geriatric acetabular fractures. The cases of 68 patients aged ≥ 65 years (mean 71 years) treated with ORIF were analyzed. MI was present in 12 fractures (67%) and an RI of the weight-bearing surface was present in 24 (46%) of the potential fracture types. Regarding the reduction quality, 54% of the reductions were graded as anatomical, 37% as imperfect, and 9% as poor. In the clinical evaluations of the 45 patients who had > 1-year follow-up (follow-up rate: 66.2%), 18% were graded as excellent, 53% as good, 16% as fair, and 13% as poor. An anatomic reduction was strongly associated with good or excellent clinical and radiological outcomes. CT was superior to radiographs for detecting the residual displacement postoperatively. Postoperative deep infection occurred in four patients. Three patients (6.7%) underwent a total hip arthroplasty conversion due to secondary osteoarthritis of the hip. We recommend ORIF as the preferred surgical treatment option for displaced acetabular fractures in elderly patients.

Differences between the root and horn cells of the human medial meniscus from the osteoarthritic knee in cellular characteristics and responses to mechanical stress.

BACKGROUND: Many histological, mechanical, and clinical studies have been performed on the medial meniscus posterior root attachment, as it often tears in patients with osteoarthritic knee. Medial meniscal root repair is recommended in clinical situations; however, to date, no studies have examined the differences between meniscal root and horn cells. The aim of this study was, therefore, to investigate the morphology, reaction to cyclic tensile strain, and gene expression levels of medial meniscal root and horn cells. METHODS: Meniscal samples were obtained from the medial knee compartments of 10 patients with osteoarthritis who underwent total knee arthroplasty. Root and horn cells were cultured in Dulbecco's modified Eagle's medium without enzymes. The morphology, distribution, and proliferation of medial meniscal root and horn cells, as well as the gene and protein expression levels of Sry-type HMG box 9 and type II collagen, were determined after cyclic tensile strain treatment. RESULTS: Horn cells had a triangular morphology, whereas root cells were fibroblast-like. The number of horn cells positive for Sry-type HMG box 9 and type II collagen was considerably higher than that of root cells. Although root and horn cells showed similar levels of proliferation after 48, 72, or 96 h of culture, more horn cells than root cells were lost following a 2-h treatment with 5% and 10% cyclic tensile. Sry-type HMG box 9 and α1(II) collagen mRNA expression levels were significantly enhanced in both cells after 2- and 4-h cyclic tensile strain (5%) treatment. CONCLUSIONS: Medial meniscal root and horn cells have distinct morphologies, reactions to mechanical stress, and cellular phenotypes. Our results suggest that physiological tensile strain is important to activate extracellular matrix production in horn cells.

The trend of treatment and conveyance system for upper extremity replantation in Japan: A nationwide population-based study from the Japan trauma data bank.

BACKGROUND: In Japan, microsurgical skill development and a system to transfer patients to an appropriate hospital for upper extremity amputation have been promoted; however, information about trends of replantation is limited. Therefore, the aim of this study was to clarify the trends in the treatment for upper extremity amputation using the Japan Trauma Data Bank (JTDB). METHODS: Data derived from JTDB (2004-2015) were used to quantify trends in the volume of replantation for upper extremity amputation including finger amputation. Trauma was diagnosed based on the Abbreviated Injury Scale code; a subgroup of patients who underwent replantation was delineated. We investigated patient demographics, infection rate, and characteristics of treating facilities. RESULTS: A total of 1240 patients underwent upper extremity amputation. Among these, 510 (41.1%) underwent replantation, and the rate of replantation did not change over the study period. The average age of patients who underwent or did not undergo replantation was 45.5 and 47.2 years, respectively. The proportion of the patients who were transferred to another hospital for treatment significantly decreased between 2004 (28.5%) and 2015 (16.3%) (P < 0.01). Time taken for transfer from the accident site to hospitals increased. The rate of patients who underwent replantation differed among different hospitals; however, higher-volume hospitals were more likely to perform replantation. CONCLUSION: The rate of patients transferred to another hospital decreased between 2004 and 2015; however, the rate of patients who underwent replantation remained unchanged. This suggests that the number of patients who were transported directly from the accident site to an appropriate hospital has increased, whereas the indication for care in each hospital remains unchanged. Common criteria for amputations are needed to address the differing rates of replantation among hospitals.

Treatment for postoperative infection of pathological femoral fracture after radiotherapy: two case reports and review of the literature.

INTRODUCTION: Radiation-induced pathological fractures show high nonunion and infection rates. Successful treatment of postoperative infections of these fractures without limb amputation is extremely rare. METHODS: We report two cases of postoperative infection of pathological femoral fracture after radiation therapy for soft tissue tumors. Considering the poor condition of the irradiated site, a two-staged operation was selected to create the optimal situation for bone union. The treatment involved the Masquelet technique, latissimus dorsi (LD) flap, and a free vascularized fibula graft (FVFG). In the first stage, we drastically resected the necrotic bone and the surrounding infected tissue and placed antibiotic polymethylmethacrylate space on the bone gap according to the Masquelet technique. Next, we used an Ilizarov external fixator as a temporizing stabilizer and performed the LD flap. Six weeks later, in the second stage, we changed the external fixation to plate fixation; packed the artificial bone (ß-TCP) and autograft bone to the induced membrane; and performed FVFG on the other side of the plate. As postoperative therapy, toe touch was allowed immediately, and partial weight bearing was started 2 months after second surgery. RESULTS: Both patients achieved bone union and were able to walk without postoperative complications. At the 2-year follow-up, there was no recurrence of infection. CONCLUSION: Our treatment is effective for controlling postoperative infection of radiation-induced pathological fracture.

[The Latest Glioma Surgical Support Devices and Intraoperative Applications of MRI].

We previously proposed an information-guided surgery based on objective intraoperative information to achieve a high precision and maximum resection of gliomas. In 2000, an "intelligent operating room" was constructed and put into operation as a place to train new "eyes," "hands," and "brains" for surgeons. Based on the positive experience from this room, it was subsequently developed into the Smart Cyber Operating Theater (SCOT), and from October 2019, Hyper SCOT was introduced at Tokyo Women's Medical University Hospital. This report introduces the latest surgical support devices that we have implemented in glioma surgery with Hyper SCOT. As an intraoperative image information support device, intraoperative MRI can correct brain shift, visualize residual tumor, and aid in performing maximal tumor resection, thereby greatly contributing to surgical results. As an intraoperative histological information support device, intraoperative flow cytometry can evaluate the presence of tumor cells and malignancy based on the measurement of the amount of DNA in tumor cells, and also predict the prognosis intraoperatively. Photodynamic therapy has been shown to be effective in clinical trials as an intraoperative treatment support device, and it is covered by insurance. Therefore, it is expected to be established as a standard treatment method for primary glioblastoma patients.

External iliac artery thrombosis following open reduction of acetabular fracture: a case report and literature review.

BACKGROUND: Postoperative thrombosis of the external iliac artery (EIA) following open reduction and internal fixation for acetabular fracture is extremely rare. PURPOSE: To report a patient with EIA thrombosis following open reduction and internal fixation using the modified ilioinguinal approach for acetabular fractures. STUDY DESIGN: This is a case report of a 69-year-old male with a left acetabular fracture who was treated surgically. METHODS: A 69-year-old male presented with left hip pain after a 1.5-m fall. Radiographs revealed left acetabular anterior wall and posterior hemitransverse fractures with dome impaction. Computed tomography (CT) showed atherosclerotic changes in many arteries. Open reduction and internal fixation were performed using the modified ilioinguinal approach. Adhesion around the external iliac vessels was severe, and the external iliac vein (EIV) ruptured during exposure. After EIV repair, anatomical reduction was achieved and the fracture was fixed using a reconstruction plate. Nine hours after surgery, the left lower limb showed acute ischemic symptoms. Contrast-enhanced CT indicated complete occlusion of the left EIA. The patient was immediately taken for a thrombectomy via EIA cut-down using a Fogarty catheter. Postoperatively, he had palpable dorsalis pedis and posterior tibial pulses; however, post-reperfusion compartment syndrome developed. Fasciotomy of the left leg was performed. RESULTS: At the 2-year and 4-month follow-up, he was pain-free in his hip and leg. Although he was walking with a cane, activity was limited due to a mild foot drop. CONCLUSIONS: It is very important for surgeons to consider EIA thrombosis as a potential complication following open reduction and internal fixation. In this case, EIA thrombosis could be explained by preoperative atherosclerotic changes and intraoperative vascular handling procedures. Preoperative screening and management, and meticulous surgical procedures are necessary for patients with a high risk of thrombosis.

Characteristics of patients with fragility hip fractures in the northern Kyushu district in Japan: a multicenter prospective registry based on an electronic data capture system.

Osteoporosis has become a worldwide public health problem, in part due to the fact that it increases the risk of fragility hip fractures (FHFs). The epidemiological assessment of FHFs is critical for their prevention; however, datasets for FHFs in Japan remain scarce. This was a multicenter, prospective, observational study in the northern district of Kyushu Island. Inclusion criteria were age > 60 years with a diagnosis of FHF and acquisition of clinical data by an electronic data capture system. Of 1294 registered patients, 1146 enrolled in the study. Nearly one third of patients (31.8%) had a history of previous fragility fractures. The percentage of patients receiving osteoporosis treatment on admission was 21.5%. Almost all patients underwent surgical treatment (99.1%), though fewer than 30% had surgery within 48 h after hospitalization. Bone mineral density (BMD) was evaluated during hospitalization in only 50.4% of patients. The rate of osteoporosis treatment increased from 21.5% on admission to 39.3% during hospitalization. The main reasons that prescribers did not administer osteoporosis treatment during hospitalization were forgetfulness (28.4%) and clinical judgment (13.6%). Age and female ratio were significantly higher in patients with previous FHFs than in those without. There was a significant difference in the rate of osteoporosis treatment or L-spine BMD values in patients with or without previous FHFs on admission. In conclusion, this study confirmed that the evaluation and treatment of osteoporosis and FHFs is still suboptimal in Japan, even in urban districts.

Clinical and radiographic study of partial arthrodesis for rheumatoid wrists.

OBJECTIVES: To retrospectively investigate the clinical and radiographic results of partial arthrodesis for the wrists with rheumatoid arthritis (RA). METHODS: Forty-one wrists with RA were treated by radiolunate (RL) or radiolunotriquetral (RLT) arthrodesis with ulnar head resection. The average follow-up period after surgery was 7.1 years. Preoperative radiographs of all wrists were classified according to Schulthess classification. We performed RL arthrodesis for all Type II (n = 26) and Type III wrists (n = 7), and RLT arthrodesis for Type III wrists (n = 8). Pre- and postoperative pain score (visual analog scale), grip strength, range of motion, and radiographic parameters were statistically compared. RESULTS: Pain scores in all groups were significantly improved at final follow-up (P < 0.05). Grip strength increased from 5.9 to 12.4 (kg) significantly in Type II wrists (P < 0.01), from 7.2 to 9.1 in Type III wrists after RLT arthrodesis, but decreased from 6.9 to 6.0 in Type III wrists after RL arthrodesis. In all groups, the arc of pronation and supination improved significantly (P < 0.05), and all radiographic parameters improved. CONCLUSIONS: RL arthrodesis for Type II wrists showed satisfactory clinical results. RLT arthrodesis would be a reliable method in case of unstable wrist joint.

Hyaluronan suppresses mechanical stress-induced expression of catabolic enzymes by human chondrocytes via inhibition of IL-1ß production and subsequent NF-κB activation.

OBJECTIVE: To investigate the inhibitory effect of hyaluronan (HA) on mechanical stress- induced expression of a disintegrin and metalloproteinase with thrombospondin type 1 motifs (ADAMTS)-4, -5 and matrix metalloproteinase (MMP)-13 by human chondrocytes. MATERIALS AND METHODS: Normal human articular chondrocytes were pre-incubated with or without 1.0 mg/mL HA (2700 kDa) for 12 h at 37 °C in stretch chambers, then they were exposed to uni-axial cyclic tensile strain (CTS, 0.5 Hz, 10% elongation). The expression of ADAMTS-4, -5, and MMP-13 were analyzed by real-time polymerase chain reaction and Immunocytochemistry. The concentration of IL-1ß in the supernatant was measured using enzyme-linked immunosorbent assay (ELISA). The nuclear translocation of runt-related transcription factor 2 (RUNX-2) and nuclear factor-κB (NF-κB) was examined by ELISA and immunocytochemistry, and phosphorylation of NF-κB was examined by western blotting. RESULTS: HA inhibited mRNA expression of ADAMTS-4, -5, and MMP13 after 24 h CTS via inhibition of IL-1ß secretion and NF-κB activation. However, HA failed to inhibit CTS-induced RUNX-2 expression and subsequent expression of ADAMTS-5 and MMP-13 1 h after CTS. CONCLUSIONS: Our results demonstrated that HA significantly suppressed mechanical stress-induced expression of catabolic proteases by inhibition of the NF-κB-IL-1ß pathway, but did not suppress mechanical stress-induced RUNX-2 signaling.

High energy trauma patients treated in the department of general surgery in a secondary emergency facility in Japan.

OBJECTIVE: We clarified the characteristics of the high energy trauma patients that entered the general surgery ward of Fukuoka city hospital (FCH), a 200 bed secondary emergency hospital in Japan. PATIENTS AND METHODS: Of the 7,826 total ambulance cases treated from April 2008 to March 2012 in our emergency room, 831 trauma patients who entered our hospital were analyzed. These patients were classified into a non high energy (NHE) and high energy trauma (HE) group based on the mechanisms of injuries. RESULTS: Of the 831 trauma cases, 741 (89.2%) were in the NHE and 90 (10.8%) were in the HE group. Eleven of the 741 cases (1.5%) in the NHE group and 18 of the 90 cases (20.0%) in the HE group entered the Department of General Surgery as inpatients, with the frequency being significantly higher in the latter group (p < 0.01). 11 of the 18 cases (61.1%) of Department of General Surgery in the HE group were diagnosed to have an injury severity score (ISS) of 15 or higher, and the rate of preventable trauma deaths (PTDs) of those 11 cases was 9.1% (1/11). CONCLUSIONS: The proportion of the patients that entered the Department of General Surgery was higher in the HE group than in the NHE group. The surgical departments of secondary emergency facilities are expected to contribute to the local trauma emergency systems.

Minimally Invasive Surgery for Trapezoid Nonunion: Case Report and Review of the Literature.

We report a case of trapezoid nonunion diagnosed 3 months post injury. A 25-year-old male patient felt continuous wrist pain after being injured. His radiograph showed non-union with sclerotic change and bone resorption. He was planned for surgery, and this was done using a minimally invasive technique. Via a dorsal approach, we percutaneously drilled to the nonunion site and freshened the fracture ends. Bone plugs were harvested from the iliac crest using a bone marrow biopsy needle and packed into the nonunion site. The fracture was then fixed with a cannulated headless compression screw. This procedure could be performed without injuring the ligaments around the trapezoid. The patient was immobilised for 4 weeks, and bone union was achieved 6 months after surgery. He had full range of finger and wrist motion and no pain at the final follow-up. Level of Evidence: Level V (Therapeutic).

The Effectiveness of Rehabilitation after Open Surgical Release for Trigger Finger: A Prospective, Randomized, Controlled Study.

BACKGROUND: It is not clear whether rehabilitation after surgery for trigger finger is effective. The aim of this study was to reveal its effectiveness for trigger finger. METHODS: This study was a randomized, controlled trial that included patients who underwent operations for trigger fingers. The patients in the rehabilitation group had postoperative occupational therapy (OT) for 3 months, while the patients in the control group were not referred for rehabilitation but received advice for a range of motion exercises. We evaluated the severity of trigger finger, Disability of Arm-Shoulder-Hand (DASH) score, pain-visual analogue scale (VAS), grip strength, whether they gained a full range of motion (ROM), and complications before and after surgery. RESULTS: Finally, 29 and 28 patients were included in the control and rehabilitation groups, respectively. At final follow-up, the DASH score, grip strength, and ROM were significantly improved in the rehabilitation group compared to that preoperatively. At final follow-up, pain was significantly improved in both groups from that preoperatively. There were no significant differences in the results, including the DASH score, grip strength, ROM and pain-VAS between the control and rehabilitation groups at the final follow-up. Subgroup analysis showed that there is a significant difference in the DASH score of patients doing housework or light work and those with a duration of symptoms >12 months between the control and rehabilitation groups at the final follow-up.

Outcome of unlinked total elbow arthroplasty for rheumatoid arthritis in patients younger than 50 years old.

AIMS: There are concerns regarding complications and longevity of total elbow arthroplasty (TEA) in young patients, and the few previous publications are mainly limited to reports on linked elbow devices. We investigated the clinical outcome of unlinked TEA for patients aged less than 50 years with rheumatoid arthritis (RA). METHODS: We retrospectively reviewed the records of 26 elbows of 21 patients with RA who were aged less than 50 years who underwent primary TEA with an unlinked elbow prosthesis. The mean patient age was 46 years (35 to 49), and the mean follow-up period was 13.6 years (6 to 27). Outcome measures included pain, range of motion, Mayo Elbow Performance Score (MEPS), radiological evaluation for radiolucent line and loosening, complications, and revision surgery with or without implant removal. RESULTS: The mean MEPS significantly improved from 47 (15 to 70) points preoperatively to 95 (70 to 100) points at final follow-up (p < 0.001). Complications were noted in six elbows (23%) in six patients, and of these, four with an ulnar neuropathy and one elbow with postoperative traumatic fracture required additional surgeries. There was no revision with implant removal, and there was no radiological evidence of loosening around the components. With any revision surgery as the endpoint, the survival rates up to 25 years were 78.1% (95% confidence interval 52.8 to 90.6) as determined by Kaplan-Meier analysis. CONCLUSION: The clinical outcome of primary unlinked TEA for young patients with RA was satisfactory and comparable with that for elderly patients. A favourable survival rate without implant removal might support the use of unlinked devices for young patients with this disease entity, with a caution of a relatively high complication rate regarding ulnar neuropathy.Level of Evidence: Therapeutic Level IVCite this article: Bone Jt Open 2023;4(1):19-26.

Effect of difference in fixation methods of tendon graft and the microfracture procedure on tendon-bone junction healing.

BACKGROUND: There are generally two methods of fixation for tendon grafts used in ligament reconstruction: bone tunnel fixation and anchor fixation. The microfracture (Mf) procedure is a technique to induce bleeding from the bone marrow, and the bleeding may contain cells with differentiation potential. However, few studies have compared the effects of the Mf procedure with those of the fixation methods. This study aimed to evaluate the effectiveness of the Mf procedure on two tendon graft fixation methods: histological, gene expression, tendon graft thickness, and mechanical. We especially focused our investigation on junction healing of tendon grafts and bone in the two fixation methods. METHODS: We used 20 rabbits to evaluate tendon and bone healing in a peroneal tendon graft model. The rabbit models were divided into five groups according to the combination of peroneal tendon graft fixation method and Mf technique as follows: control group (C, n = 4), bone tunnel fixation without Mf procedure group (BT - Mf, n = 4), bone tunnel fixation with Mf procedure group (BT + Mf, n = 4), anchor fixation without Mf procedure group (A - Mf, n = 4), and anchor fixation with Mf procedure group (A + Mf, n = 4). All animals were sacrificed at 4 weeks postoperatively. The specimens underwent histological evaluation, mRNA analysis, tendon graft thickness at the tendon-bone junction, and biomechanical testing. RESULTS: Histological evaluation of the BT + Mf and A + Mf groups showed healing with fibrocartilage formation at the tendon graft-bone junction. The mRNA expression showed significant increase in type 2 collagen, Scleraxis, and SRY-box9 in the BT + Mf and A + Mf groups. In biomechanical tests, the BT + Mf and A + Mf groups showed significantly increased tensile strength compared with the BT - Mf and A - Mf groups (BT + Mf group, 21.6 ± 1.7 N; A + Mf group, 22.5 ± 2.3 N vs. BT - Mf group, 12.3 ± 2.4 N; A - Mf group, 11 ± 2.3 N). CONCLUSION: The Mf procedure resulted in fibrocartilage formation at the tendon-bone junction in the BT and anchor fixation and improved the fixation strength at 4 weeks.

Risk Factors for Infection Following Operative Treatment of Traumatic Upper Extremity Amputation Injury.

Background: Identification of the risk factors for surgical site infection (SSI) can be a straightforward and cost-effective measure to reduce or prevent the occurrence of SSI. However, there are no studies that revealed risk factors for SSI for traumatic upper extremity amputation. The aim of this study is to investigate the risk factors that promote SSI after surgery for traumatic upper extremity amputation using a large nationwide database. Methods: We used data from the Japan Trauma Data Bank. Diagnoses were defined using the Abbreviated Injury Scale code. We applied multivariate logistic regression to evaluate the infection risk factor. We chose age, sex, vital signs, cause and type of trauma, concomitant injury, diabetes, amputation level, Glasgow coma scale, Injury Severity Score (ISS) and blood transfusion within 24 hours following hospital arrival as confounders. Receiver operating characteristic (ROC) curve analysis was adopted to identify thresholds for change in infection risk. We also applied propensity score (PS) matching to adjust for confounding factors that may affect the outcome. Results: A total of 1,150 patients (967 males, 183 females) had traumatic upper extremity amputation. The mean patient age was 46.5 years. A total of 21 patients (1.8%) suffered from SSI. ISS, blood transfusion, systolic blood pressure (BP) and the upper extremity amputation except for finger were identified as the independent significant risk factors for SSI occurrence by the multivariate analysis (p < 0.05, p < 0.005, p < 0.05 and p < 0.005, respectively). ROC modelling revealed that patients with ISS of over 9 or systolic BP of over 160 had a risk for SSI. After PS matching, the patients with blood transfusion or systolic BP of over 160 had a significantly higher risk of infection (OR 9.0; p = 0.01 and OR 7.0; p = 0.03, respectively). Conclusions: In treating patients with these risk factors, we must be especially careful in performing thorough debridement and wound care. Level of Evidence: Level II (Therapeutic).

The effect of mechanical stress on enthesis homeostasis in a rat Achilles enthesis organ culture model.

Tendons and ligaments are jointed to bones via an enthesis that is essential to the proper function of the muscular and skeletal structures. The aim of the study is to investigate the effect of mechanical stress on the enthesis. We used ex vivo models in organ cultures of rat Achilles tendons with calcaneus including the enthesis. The organ was attached to a mechanical stretching apparatus that can conduct cyclic tensile strain. We made the models of 1-mm elongation (0.5 Hz, 3% elongation), 2-mm elongation (0.5 Hz, 5% elongation), and no stress. Histological evaluation by Safranin O staining and Toluidin Blue and Picro Sirius red staining was conducted. Expression of sex-determining region Y-box 9 (Sox9), scleraxis (Scx), Runt-related transcription factor 2 (Runx2), and matrix metalloproteinase 13 (Mmp13) were examined by real-time polymerase chain reaction and immunocytochemistry. Terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate biotin nick end-labeling and live/dead staining and was conducted for evaluation of the apoptosis and cell viability. The structure of the enthesis was most maintained in the model of 1-mm elongation. The electronic microscope showed that the enthesis of the no stress model had ill-defined borders between fibrocartilage and mineralized fibrocartilage, and that calcification of mineralized fibrocartilage occurred in the model of 2-mm elongation. Sox9 and Scx was upregulated by 1-mm elongation, whereas Runx2 and Mmp13 were upregulated by 2-mm elongation. Apoptosis was inhibited by low stress. The results of this study suggested that 1-mm elongation can maintain the structure of the enthesis, while 2-mm elongation promotes degenerative changes.