The characteristic arthroscopic 'eyelid- turnup' sign indicated for partial-thickness longitudinal medial meniscus tear.

BACKGROUND: Medial posterior horn meniscal tear is difficult to be visualized in full view during arthroscopy and is occasionally undetected when the superior surface seems intact. OBJECTIVE: The purpose of this study is to describe a characteristic arthroscopic sign indicating the occult partial-thickness longitudinal medial meniscus tear extending only to the inferior articular surface. METHODS: This study was a retrospective analysis of available arthroscopic knee surgery between January 2016 and December 2017. The videos were studied and data was recorded for the number of cases showing the presence of 'eyelid-turnup' sign and coexisting partial-thickness medial meniscus tear. Sensitivity and positive predictive value of the sign were calculated. RESULTS: Of all the 491 videos of medial meniscal tear available for review, partial-thickness longitudinal medial meniscus was torn in 26 cases. Six out of 26 patients could be diagnosed with partial-thickness longitudinal tear under direct vision. Of the other 20 patients which could not be diagnosed under direct vision during arthroscopy until the tear was pressed by a probe, 17 patients were diagnosed by the positive 'eyelid-turnup' sign. The other 3 patients showed negative 'eyelid-turnup' sign and were then diagnosed by the hints of preoperative MRI and intra-operative exploration. The sensitivity of the sign was 85%; the positive predictive value was 89.5%. CONCLUSIONS: The 'eyelid-turnup' sign of meniscus pressed by a probe at arthroscopy is a characteristic indicator for occult inferior partial-thickness longitudinal tears of midbody and posterior horn. Early identification of this special sign may help reduce the likelihood that the occult partial-thickness longitudinal tear will be missed during arthroscopy.

Baicalein Accelerates Tendon-Bone Healing via Activation of Wnt/ß-Catenin Signaling Pathway in Rats.

BACKGROUND: Tendon-bone healing is a reconstructive procedure which requires a tendon graft healing to a bone tunnel or to the surface of bone after the junction injury between tendon, ligament, and bone. The surgical reattachment of tendon to bone often fails due to regeneration failure of the specialized tendon-bone junction. MATERIALS AND METHODS: An extra-articular tendon-bone healing rat model was established to discuss the effect of the baicalein 10 mg/(kg·d) in accelerating tendon-bone healing progress. Also, tendon-derived stem cells (TDSCs) were treated with various concentrations of baicalein or dickkopf-1 (DKK-1) to stimulate differentiation for 14 days. RESULTS: In vivo, tendon-bone healing strength of experiment group was obviously stronger than the control group in 3 weeks as well as in 6 weeks. And there were more mature fibroblasts, more Sharpey fibers, and larger new bone formation area treated intragastrically with baicalein compared with rats that were treated with vehicle for 3 weeks and 6 weeks. In vitro, after induction for 14 days, the expressions of osteoblast differentiation markers, that is, alkaline phosphatase (ALP), runt-related transcription factor 2 (Runx2), osteocalcin (OCN), osterix (OSX), and collagen I, were upregulated and Wnt/ß-catenin signaling pathway was enhanced in TDSCs. The effect of DKK-1 significantly reduced the effect of baicalein on the osteogenic differentiation. CONCLUSION: These data suggest that baicalein may stimulate TDSCs osteogenic differentiation via activation of Wnt/ß-catenin signaling pathway to accelerate tendon-bone healing.

[Osteopractic total flavone promoting rat extra-articular tendon-bone healing through mTOR pathway].

OBJECTIVE: To explore function and related molecular mechanism of osteopractic total flavone (OTF) on tendon healing in rats. METHODS: Ten male rats aged for 8 weeks were collected and weighted from 180 to 220 g. Tendon stem cells were cultivated, the third tendon stem cells were used for experiment. OTP treated with 0, 0.1, 1, 10 ng/ml were added into tendon stem cells, and expression change of ALP, Runx2, OCN, VEGF, P-S6, P-4E/BP1 were detected after 14 days. Forty male rats aged for 8 weeks (weighted 180 to 220 g) were established extra-articular tendon-bone transplanting healing model, and divided into experimental group and control group. Experimental group were treated with OTF(100 mg·kg⁻¹·d⁻¹), while control group was treated by normal saline with the same volume. Tendon-bone healing degree were detected by biomechanical testing at 3 and 6 weeks after surgery, histological detection were applied to detect tendon-bone healing and number of new vessles. RESULTS: After treated by OTP, ALP staining and active index detection showed there were statistical differences among 0, 0.1, 1, 10 ng/ml group. After 14 days' cultivation, western blotting results showed mTOR downstream marker protein P-S6 protein expression were gradually increased with increase of density of OTP, expression of P-4E/BP1 was reduced, while expression of Runx2, OCN, VEGF were increased. Biological detection results showed that there was no significant difference in mechanical strength between experimental group(0.78±0.05) N/mm and control group (0.51±0.02) N/mm at 3 weeks after surgery, while mechanical strength in experimental group (1.36±0.09) N/mm was higher than control group (1.01±0.08) N/mm at 6 weeks after surgery. Histological results showed maturity of tendon-bone surface cell were higher at 3 and 6 weeks in experimental group, sharpey fiber growth more density, calcification extent of mesenchyme was high, and new bone, vessels were increased. CONCLUSIONS: OTF could promote osteogenic differentiation of tendon stem cells through mTOR signaling in vitro, and stimulate tendon-bone healing in bone tunnel and enhance connection quality between tendon and bone.

Arthroscopic revision release of gluteal muscle contracture after failed primary open surgery.

PURPOSE: The treatment of gluteal muscle contracture (GMC) after failed primary open release surgery has rarely been reported in the literature. GMC is a troublesome health problem in some developing countries, and it can result in the limitation of patients' hip function, leading to the development of inferiority complexes. The aim of this study is to evaluate the effect of arthroscopic revision surgery after failed primary open release on patients with GMC. METHODS: A total of 278 hips of 140 patients who underwent arthroscopic revision procedures after failed primary open surgeries were gathered from the department files. All patients were treated using a "three-step" arthroscopic release procedure by the same surgeon group. RESULTS: The mean follow-up for the 136 patients was 38.9 months. There was significant difference (P < 0.05) between the patients' mean post-revision and pre-operative results on the Harris scoring system. Unreleased contracture tissues that needed revision operations included the gluteus maximus, tensor fasciae latae muscle, and gluteus medius in all patients, and the gluteus minimus and hip capsule in 11.0% and 8.1% of patients, respectively. Short-term complications included subcutaneous bruising of the abdomen in 11 patients, extensive ecchymosis in the lateral thigh in 12 patients, and a transient reduction of muscle strength in all patients. No complications involving postoperative incision infection, nerve and blood vessel damage, or positive Trendelenburg sign occurred. Symptoms of hip snapping and limitation of range of motion (ROM), combined with a positive Trendelenburg sign in two patients after the primary open surgery, were all resolved except for the Trendelenburg sign through arthroscopic revision release. The overall satisfaction rate of the revision operations was 90.4%. CONCLUSION: The three-step arthroscopic release procedure is effective for failed primary open GMC surgeries as shown by improved post-operative function and patient satisfaction regardless of which primary procedure was performed.