Do Magnets Have the Potential to Serve as a Stabilizer for the Shoulder Joint in Massive Rotator Cuff Tears?: A Biomechanical Cadaveric Study.

Background: Disruption of the rotator cuff muscles compromises concavity compression force, which leads to superior migration of the humeral head and loss of stability. A novel idea of using the magnetic force to achieve shoulder stabilization in massive rotator cuff tears (MRCTs) was considered because the magnets can stabilize two separate entities with an attraction force. This study aimed to investigate the biomechanical effect of the magnetic force on shoulder stabilization in MRCTs. Methods: Seven fresh frozen cadaveric specimens were used with a customized shoulder testing system. Three testing conditions were set up: condition 1, intact rotator cuff without magnets; condition 2, an MRCT without magnets; condition 3, an MRCT with magnets. For each condition, anterior-posterior translation, superior translation, superior migration, and subacromial contact pressure were measured at 0°, 30°, and 60° of abduction. The abduction capability of condition 2 was compared with that of condition 3. Results: The anterior-posterior and superior translations increased in condition 2; however, they decreased compared to condition 2 when the magnets were applied (condition 3) in multiple test positions and loadings (p < 0.05). Abduction capability improved significantly in condition 3 compared with that in condition 2, even for less deltoid loading (p < 0.05). Conclusions: The magnet biomechanically played a positive role in stabilizing the shoulder joint and enabled abduction with less deltoid force in MRCTs. However, to ensure that the magnet is clinically applicable as a stabilizer for the shoulder joint, it is necessary to thoroughly verify its safety in the human body and to conduct further research on technical challenges.

Clinical, radiological, and histological outcomes after the fibrin-matrix autologous chondrocyte implantation for chondral lesions of the knee in patients more than 50 years old: A prospective case series with minimum 2-year follow-up.

BACKGROUND: The purpose of this study was to evaluate clinical and radiological outcomes and to analyze the histological findings of repaired cartilage in patients more than 50 years old with underwent fibrin-matrix autologous chondrocyte implantation (ACI). METHODS: From January 2013 to February 2014, a prospective study was conducted on 16 patients (16 knees) who underwent fibrin-matrix ACI for International Cartilage Repair Society grade 3 or 4 chondral lesions of the knee. The major lesion was in the medial femoral condyle in all patients. The mean age of the patients was 58.1 ± 6.2 (range 51-66) years, and the minimum follow-up period was 2 years. All patients had clinical and radiological evaluations at 3 months, 6 months, 1 year, and 2 years after surgery. Twelve patients had second-look arthroscopies at 1 year after surgery, and implanted chondral biopsies were performed in 11 of these 12 patients for histological analysis. RESULTS: Functional disability assessment scales for the knee significantly improved after fibrin-matrix ACI (p < 0.05). The visual analog scale score significantly decreased from 6.7 ± 1.2 to 2.0 ± 1.8 (p < 0.001). The mean modified magnetic resonance observation of cartilage repair tissue score was 83.8 ± 17.3 at 1 year after surgery and 74.0 ± 19.2 at 2 years after surgery. Repair of the tissue with hyaline cartilage was confirmed histologically. CONCLUSIONS: Satisfactory clinical and radiological outcomes were obtained from gel-type fibrin-matrix ACI technique in older patients with a cartilage defect of the knee. Histological analysis confirmed that the new repaired tissue with hyaline cartilage filled the cartilage defect area. Therefore, fibrin-matrix ACI is believed to be an applicable treatment for older patients with chondral lesions of the knee. LEVEL OF EVIDENCE: Level IV.

Distal clavicle fracture treated with a titanium elastic nail (TEN).

It is generally known to use internal fixation using a hook plate or Kirschner wire as an operative treatment for distal clavicle fracture. TEN is a surgical technique that is mainly used in clavicle mid-shaft fracture, and there is no reported case for distal clavicle. We report a case of distal clavicle fracture treated with TEN. A 19-year-old man came to the emergency department with right shoulder pain after bicycle accident. The radiographs showed a distal clavicle fracture without apparent disruption of the acromioclavicular joint (AC-joint) and classification with a Neer type IIA fracture pattern. One day after trauma the patient was treated with closed reduction and internal fixation using a titanium elastic nail (TEN). At 6 months postoperatively, there was no complication and radiograph showed good distal clavicle union. Therefore we performed removal of a TEN.

Relationship between Locations of Facial Injury and the Use of Bicycle Helmets: A Systematic Review.

The aim of this study is to review the protective effect of a bicycle helmet on each facial location systematically. PubMed was searched for articles published before December 12, 2014. The data were summarized, and the odds ratio (OR) between the locations of facial injury was calculated. A statistical analysis was performed with Review Manager (The Nordic Cochrane Centre). Bicycle helmets protect the upper and middle face from serious facial injury but do not protect the lower face. Non-wearers had significantly increased risks of upper facial injury (OR, 2.07; P<0.001) and of middle facial injury (OR, 1.97; P<0.001) as compared to helmet users. In the case of lower facial injury, however, only a slightly increased risk (OR, 1.42; 95% confidence interval (CI), 0.67-3.00, P=0.36) was observed. The abovementioned results can be attributed to the fact that a helmet covers the head and forehead but cannot cover the lower face. However, helmets having a chin cap might decrease the risk of lower facial injury.