The Arthroscopic "Bellows" Sign Identifies Hidden Rotator Cuff Tears.

The intraoperative recognition of rotator cuff tears continues to be a challenge in some cases, despite clinical suspicion, a physical examination suggesting a rotator cuff tear, and detection on preoperative imaging studies. Intraoperative identification can be elusive in partial tears including intratendinous tears and obscured full-thickness tears. The purpose of this Technical Note, and the associated technique video, is to discuss a visual sign for the detection of various rotator cuff tear pathologies. Derived from the dynamic fluid expansion and contraction of the affected tissues, this indicator is termed the arthroscopic "bellows" sign.

Revision Posterior Cruciate Ligament Surgery.

Successful posterior cruciate ligament (PCL) reconstruction surgery results from identification and treatment of associated pathology such as posterolateral instability, posteromedial instability, and lower extremity malalignment. The use of strong graft material, properly placed tunnels to as closely as possible approximate the PCL insertion sites, and minimization of graft bending also enhance the probability of PCL reconstruction success. In addition, mechanical graft tensioning, primary and back-up PCL graft fixation, and the appropriate postoperative rehabilitation program are also necessary ingredients for PCL reconstruction success. Both single-bundle and double-bundle PCL reconstruction surgical techniques are successful when evaluated with stress radiography, KT 1000 arthrometer measurements, and knee ligament rating scales. PCL reconstruction failure may result when any or all of these surgical principles are violated. The purpose of this manuscript was to discuss revision PCL surgery. This presentation will include causes of unsuccessful PCL reconstruction, surgical indications and goals, patient evaluation, surgical decision making, graft selection, surgical technique, associated surgical procedures, postoperative rehabilitation, and revision PCL reconstruction results.

The Mini C-arm Adds Quality and Efficiency to the Pediatric Orthopedic Outpatient Clinic.

The mini C-arm has become increasingly popular in the practice of orthopedics. To the authors' knowledge, its use in the pediatric orthopedic outpatient clinic has not been reported. The purpose of this study was to evaluate the practice efficiency and radiation exposure to the patient when the mini C-arm was used in the pediatric orthopedic outpatient clinic. One hundred consecutive midshaft and distal forearm fractures were evaluated by one orthopedic surgeon in follow-up using a mini C-arm. For each case, the radiation physicist calculated the amount of skin exposure in milligray (mGy). The average skin exposure to the patient from the mini C-arm was 0.58 mGy, compared with 0.2 mGy for anteroposterior view and lateral view radiographs. Use of the mini C-arm, in place of plain radiographs obtained in the radiology department, decreased time waiting during clinic visits by 23 minutes. This study reports 2 important findings. First, surprisingly, the mini C-arm used a slightly higher radiation dose than standard imaging with plain radiographs. Second, use of the mini C-arm saved time and improved the efficiency of the clinic visit. Overall, the mini C-arm improves quality and efficiency in the pediatric orthopedic outpatient clinic. [Orthopedics. 2016; 39(6):e1097-e1099.].

In-Toeing Is Often a Primary Care Orthopedic Condition.

OBJECTIVE: To evaluate in-toeing consults to a pediatric orthopedic clinic to determine the proportion that could be managed by a primary care physician. STUDY DESIGN: A prospective registry was created for 143 consecutive children referred to a pediatric orthopedic clinic for "in-toeing." Each patient underwent a careful history and physical examination, which included a rotational profile. We recorded the final diagnosis, treatment offered, follow-up visit results, and the source of the referral. RESULTS: After pediatric orthopedic evaluation, 85% of patients had a confirmed diagnosis of in-toeing, and 15% had a different final diagnosis. Seventy-four percent of patients had 1 consultation visit, 18% had 2, and 8% had >2 visits. None of the referred patients was a candidate for treatment by casting or surgery. CONCLUSION: In most cases, in-toeing is a normal variation of development that can be managed by counseling and observation by the primary care physician alone. Rare cases of severe in-toeing >2 standard deviations from the mean should likely still prompt referral to a pediatric orthopedic surgeon for potential intervention.

Combined anterior cruciate ligament and posterolateral reconstruction of the knee using allograft tissue in chronic knee injuries.

Combined anterior cruciate ligament (ACL) and posterolateral injury of the knee can result in significant functional instability for the affected individual. Both components of the instability must be treated to maximize the probability of success for the surgical procedure. Higher failure rates of the ACL reconstruction have been reported when the posterolateral instability has been left untreated. The purpose of this article is to describe our surgical technique, and present the results of 34 chronic combined ACL posterolateral reconstructions in 34 knees using allograft tissue, and evaluating these patient outcomes with KT 1000 knee ligament arthrometer, Lysholm, Tegner, and Hospital for Special Surgery knee ligament rating scales. In addition, observations regarding patient demographics with combined ACL posterolateral instability, postoperative range of motion loss, postinjury degenerative joint disease, infection rate, return to function, and the use of radiated and nonirradiated allograft tissues will be presented.

Mechanisms for the reaction of thiophene and methylthiophene with singlet and triplet molecular oxygen.

Mechanisms for the reaction of thiophene and 2-methylthiophene with molecular oxygen on both the triplet and singlet potential energy surfaces (PESs) have been investigated using ab initio methods. Geometries of various stationary points involved in the complex reaction routes are optimized at the MP2/6-311++G(d, p) level. The barriers and energies of reaction for all product channels were refined using single-point calculations at the G4MP2 level of theory. For thiophene, CCSD(T) single point energies were also determined for comparison with the G4MP2 energies. Thiophene and 2-methylthiophene were shown to react with O(2) via two types of mechanisms, namely, direct hydrogen abstraction and addition/elimination. The barriers for reaction with triplet oxygen are all significantly large (i.e., >30 kcal mol(-1)), indicating that the direct oxidation of thiophene by ground state oxygen might be important only in high temperature processes. Reaction of thiophene with singlet oxygen via a 2 + 4 cycloaddition leading to endoperoxides is the most favorable channel. Moreover, it was found that alkylation of the thiophene ring (i.e., methyl-substituted thiophene) is capable of lowering the barrier height for the addition pathway. The implication of the current theoretical results may shed new light on the initiation mechanisms for combustion of asphaltenes.