Poor Prognostic Factors in Patients With Rotator Cuff Retear.

BACKGROUND: The treatment for retears after arthroscopic rotator cuff repair (ARCR) has long been a challenge. PURPOSE: This study aimed to (1) summarize the characteristics of patients with a retear after primary ARCR and (2) determine the risk factors for poor clinical outcomes after a retear. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: We collected the data of patients with a retear after primary ARCR between January 2011 and December 2016. There were 45 patients with retears included (19 men [42.2%] and 26 women [57.8%]; mean ± SD age, 63.11 ± 8.87 years). Initially, the demographic and outcome data of patients with a retear were analyzed. Patients were classified into good and poor outcome groups according to their overall satisfaction at final follow-up. Univariable and multivariable logistic regression analyses were performed to determine the factors for poor clinical outcomes after a retear. RESULTS: A total of 31 patients were classified into the good outcome group, and 14 patients were classified into the poor outcome group. Both the good and the poor outcome groups showed that clinical scores significantly improved at the time of the retear diagnosis, but the final scores were maintained or worse compared with scores at the time of the retear diagnosis. Final range of motion (ROM), except external rotation in the good outcome group, was worse or had no significant change compared with ROM at the time of the retear diagnosis. On multivariable logistic regression analysis, current smoking (odds ratio [OR], 45.580 [95% CI, 3.014-689.274]; P = .006), female sex (OR, 32.774 [95% CI, 2.433-441.575]; P = .009), and retears of the same or larger size than the initial tear (OR, 10.261 [95% CI, 1.544-68.202]; P = .016) showed a higher OR for poor clinical outcomes after a retear. CONCLUSION: Smoking, female sex, and retears of the same or larger size than the initial tear were independent risk factors for poor clinical outcomes after a rotator cuff retear. Final clinical scores and ROM were similar or worse compared with the scores and ROM at the time of the retear diagnosis. Therefore, revision surgery should be actively considered in female patients or those who smoke with poor clinical outcomes and a larger retear size than the preoperative tear size at the time of the retear diagnosis.

Engineered Cell Sheets for the Effective Delivery of Adipose-Derived Stem Cells for Tendon-to-Bone Healing.

BACKGROUND: Efforts are being made to treat rotator cuff tears (RCTs) that exhibit poor healing and high retear rates. Tendon-to-bone healing using mesenchymal stem cells is being explored, but research is needed to establish effective delivery options. PURPOSE: To evaluate the effects of an adipose-derived stem cell (ADSC) sheet on mesenchymal stem cell delivery for tendon-to-bone healing of a chronic RCT in rats and to demonstrate that ADSC sheets enhance tendon-to-bone healing. STUDY DESIGN: Controlled laboratory study. METHODS: Mesenchymal stem cells were obtained from rat adipose tissue, and a cell sheet was prepared using a temperature-responsive dish. To evaluate the efficacy of stem cells produced in a sheet for the lesion, the experiment was conducted with 3 groups: repair group, cell sheet transplantation after repair group, and cell sheet-only group. Histological, biomechanical, and micro-computed tomography (micro-CT) results were compared among the groups. RESULTS: Hematoxylin and eosin staining for histomorphological analysis revealed that the cell sheet transplantation after repair group (5.75 ± 0.95) showed statistically significant higher scores than the repair (2.75 ± 0.50) and cell sheet-only (3.25 ± 0.50) groups (P < .001). On safranin O staining, the cell sheet transplantation after repair group (0.51 ± 0.04 mm2) had a larger fibrocartilage area than the repair (0.31 ± 0.06 mm2) and cell sheet-only (0.32 ± 0.03 mm2) groups (P = .001). On micro-CT, bone volume/total volume values were significantly higher in the cell sheet transplantation after repair group (23.98% ± 1.75%) than in the other groups (P < .039); there was no significant difference in the other values. On the biomechanical test, the cell sheet transplantation after repair group (4 weeks after repair) showed significantly higher results than the other groups (P < .005). CONCLUSION: Our study shows that engineered stem cells are a clinically feasible stem cell delivery tool for rotator cuff repair. CLINICAL RELEVANCE: This laboratory study provides evidence that ADSCs are effective in repairing RCTs, which are common sports injuries.

Anatomically Precontoured Locked Plates in Pilon Fractures: A Computed Tomography Based and Cadaveric Study.

BACKGROUND: The treatment of comminuted tibia plafond fractures remains clinically challenging due to the complexity of the articular fracture pattern despite using the anatomically precontoured locked plates. This study describes the morphologic characteristics of the anterolateral fragment and to evaluate the fixability of the anterolateral fragment with the anatomically precontoured locked plate in the pilon fracture. MATERIALS AND METHODS: One hundred and twenty five cases of AO 43-B and C fracture were evaluated using the computed tomography (CT) scan. The anterior-posterior distance in CT (APDc), medial-lateral distance in CT (MLDc), coronal and sagittal height, and articular surface area of the anterolateral fragment were measured in CT. Four types of anatomically precontoured locked plates were used for cadaveric measurement. Four cadaveric parameters were also evaluated; anteroposterior distance in plate (APDp), height of the screw in the medial plate, medial-lateral distance in plate (MLDp), and height of the screw in the anterolateral plate. RESULTS: The anterolateral fragment was described with a mean surface area of 167.13 mm2 (APDc: 10.89 ± 4.64 mm, MLDc: 15.02 ± 6.56 mm, sagittal height: 14.85 ± 6.25 mm, and coronal height: 17.27 ± 6.88 mm). The cadaveric measurement showed that the juxta-articular screw of the medial distal tibia plate was placed away from the anterolateral fragment. The anterolateral distal tibia plate did not purchase the anterolateral fragment due to the higher position of the most distal-lateral screw (Synthes 18.37 ± 1.86 mm and Zimmer 17.78 ± 2.37 mm of the height of screw in the anterolateral plate). CONCLUSION: Anatomical distal tibial locked plates did not take purchase on the anterolateral fragment in pilon fracture in the best anatomical fit. Preoperative CT measurement can be used for determining a fixation strategy for the anterolateral fragment. In addition, a newly designed anterolateral distal tibia plate can be another solution when the usual anatomically precontoured distal tibia locked plate fails to cover the anterolateral fragment.