Modification of Humeral Component Results in Increased Impingement Free Range of Motion in a Reverse Shoulder Arthroplasty Model.

Introduction: Shoulder arthroplasties have been demonstrated to provide reliable pain relief as well as functional benefits. The advent of the reverse shoulder arthroplasty allowed for expanded indications for shoulder replacement. Several studies comparing the outcomes of anatomic and reverse total shoulder arthroplasties have demonstrated decreased range of motion in the reverse arthroplasty cohort, especially in internal rotation. The authors hypothesized that slight modifications to the humeral component of a reverse shoulder arthroplasty could result in increased impingement free range of motion without significant sacrifices to stability. Methods: A reverse shoulder arthroplasty model was fashioned to mimic a setting of anterior mechanical impingement after replacement. Sequential resections were taken from the anterior aspect of the polyethylene up to a resection of 10 mm. A solid modeling software was utilized to compare the experimental group to the control group with regard to impingement free motion. Finite element analysis was subsequently utilized to assess stability of the construct in comparison to the nonmodified polyethylene. Results: Impingement free internal rotation increased minimally at 3 mm of resection but considerably at each further increase in resection. A resection of 10 mm resulted roughly 30% improvement in impingement free internal rotation. Instability in this model increased with modifications beyond 7 mm. Conclusion: Slight alterations to the geometry of the humeral tray and polyethene components can result in improvements in impingement-free internal rotation without substantial increased instability in this model. Further work is needed to determine in vivo implications of modifications to the humeral tray and polyethylene.

Sex-Based Differences in Patient-Reported Outcomes After Arthroscopic Rotator Cuff Repair.

BACKGROUND: Rotator cuff repair is one of the most common surgical procedures performed on the shoulder. Previous studies have indicated that pain and disability can vary significantly between patients with similarly appearing rotator cuff tears on diagnostic imaging. Prior literature has compared functional outcomes between operative and nonoperative treatments as well as variability in surgical techniques. However, few studies have examined postoperative outcomes based on patient factors such as sex. PURPOSE: To compare patient-reported outcomes after rotator cuff repair between men and women. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: A total of 283 patients (153 male, 130 female) who underwent primary arthroscopic rotator cuff repair were included in this study; of those, 275 patients (97.2%) completed 1-year follow-up. Patient-reported pain visual analog scale (VAS), Veterans RAND 12-item Health Survey (VR-12 mental and physical components), American Shoulder and Elbow Surgeons (ASES), and Single Assessment Numeric Evaluation (SANE) scores were collected preoperatively and at 2 weeks, 6 weeks, 3 months, 6 months, and 1 year postoperatively using an electronic outcomes system. RESULTS: Women reported higher VAS pain scores when compared with men preoperatively (P < .01) and at 2 weeks (P < .01), 6 weeks (P < .01), and 3 months (P = .02) postoperatively. Additionally, women experienced a greater overall change in the mean VAS score preoperatively when compared with 1 year postoperatively (P < .01). The use of narcotic pain medication 2 weeks after surgery was greater in women (P = .032). Women had significantly lower preoperative VR-12 mental scores (P = .03) and experienced a greater increase in the mean VR-12 mental score preoperatively when compared with 1 year postoperatively (P < .01). Men had higher ASES scores preoperatively (P < .01) and at 3 months postoperatively (P < .01). Women experienced a greater overall change in the ASES score preoperatively when compared with 1 year postoperatively (P < .01). CONCLUSION: Women reported greater pain and decreased shoulder function compared with men during the initial 3 months after arthroscopic rotator cuff repair. There were no sex-based differences in patient-reported outcomes at 1-year follow-up. The results of this study indicate that there are sex-related differences in the early postoperative recovery of patients undergoing rotator cuff repair, contributing to postoperative expectations for both clinicians and patients alike.

Patellar instability.

Patellar instability is a common injury that can result in significant limitations of activity and long-term arthritis. There is a high risk of recurrence in patients and operative management is often indicated. Advances in the understanding of patellofemoral anatomy, such as knowledge about the medial patellofemoral ligament, tibial tubercle-trochlear groove distance, and trochlear dysplasia may allow improved surgical management of patellar instability. However, techniques such as MPFL reconstruction are technically demanding and may result in significant complication. The role of trochleoplasty remains unclear.

Missed peritalar injuries: an analysis of factors in cases of known delayed diagnosis and methods for improving identification.

UNLABELLED: Because of the complex anatomy of the foot, rarity of fractures of the foot, and subtle radiographic cues, foot injuries are commonly overlooked and mis/undiagnosed. This study seeks to investigate a patient population whose peritalar injuries, including fractures and dislocations, were missed on initial examination, in order to analyze factors of known, missed injuries and provide insight into methods for reducing the incidence of missed diagnoses. Surgical cases between January 1999 and May 2011 were queried and retrospectively reviewed to identify missed peritalar injuries. Of 1682 surgical cases reviewed, 27 patients with missed peritalar injury(ies), which were subsequently confirmed by imaging studies, were identified. Using the Orthopaedic Trauma Association classification, fracture and dislocation subtypes were classified. A medical record review was performed to assess demographic and surgical data elements. In this study population, 7 types of peritalar injuries (talus, calcaneal, navicular, and cuboid fractures as well as subtalar, calcaneocuboid, and talonavicular joint dislocations) were diagnosed in 27 patients. All patients required surgical intervention. Talus fractures were the most commonly missed injury. In patients with multiple peritalar injuries, there was a strong correlation between talus and navicular fractures (r = -0.60; P < .01) as well as a moderate correlation between talus fractures and calcaneocuboid dislocations (r = -0.46; P = .02). The presence of a calcaneal fracture significantly decreased the time to definitive diagnosis (P = .01). Male patients' diagnoses were delayed an average of 324 days and females 105 days (P = .04). A moderate correlation was found between patient age at injury and time to diagnosis (r = -0.47; P = .04), with a decreased time to diagnosis as patient age increased. Significant factors were identified in this patient population, including patient sex and age, which may contribute to missed or delayed diagnosis in the clinical setting. Prompt and accurate diagnosis of peritalar injuries may improve long-term outcomes. LEVELS OF EVIDENCE: Care Management, Level V.

Patellar instability.

Patella instability can cause significant pain and functional limitations. Several factors can predispose to patella instability, such as ligamentous laxity, increased anterior TT-TG distance, patella alta, and trochlear dysplasia. Acquired factors include MPFL injury or abnormal quadriceps function. In many cases, first-time dislocation can successfully be managed with physical therapy and other nonoperative management; however, more than one dislocation significantly increases the chance of recurrence. Surgical management can improve stability, but should be tailored to the injuries and anatomic risk factors for recurrent dislocation. Isolated lateral release is not supported by current literature and increases the risk of iatrogenic medial instability. Medial repair is usually reserved for patients with largely normal anatomy. MPFL reconstruction can successfully stabilize patients with medial soft tissue injury but is a technically demanding procedure with a high complication rate and risks of pain and arthrosis. Tibial tubercle osteotomy can address bony malalignment and also unload certain articular cartilage lesions while improving stability. Trochleoplasty may be indicated in individuals with a severely dysplastic trochlea that cannot otherwise be stabilized. A combination of procedures may be necessary to fully address the multiple factors involved in causing pain, loss of function, and risk of recurrence in patients with patellar instability.

Diagnosis of Wilms' tumor using near-infrared Raman spectroscopy.

PURPOSE: Raman spectroscopy has distinguished malignant from normal tissues in several types of cancer. This is the first report of applying Raman spectroscopy to the diagnosis of Wilms' tumor. METHODS: Specimens of normal kidney, Wilms' tumor, xanthogranuloma, nephrogenic rests, and rhabdoid tumor were collected fresh from the operating room. Specimens of Wilms' tumor, normal kidney, and congenital mesoblastic nephroma were retrieved from the cryobank and thawed to room temperature. At least 12 Raman spectra were collected from each tissue sample. Histologic slides of each specimen were reviewed by pediatric pathologists. A computer algorithm based on discriminant function analysis (DFA) classified the Raman spectra of Wilms' tumor and the normal sample. RESULTS: Four hundred sixty-seven spectra were collected from 41 specimens. Using DFA, Raman spectroscopy differentiated Wilms' tumor from normal with 100% sensitivity and specificity and treated from untreated Wilms' tumor with 100% sensitivity and specificity. Using a DFA model built from cryopreserved specimens but applied to fresh Wilms' and normal samples, the sensitivity and specificity were 93.3% and 90.9%, respectively. CONCLUSION: Raman spectroscopy is an accurate technique for differentiating Wilms' tumor from normal kidney and treated from untreated Wilms' tumor. It has potential to diagnose in minutes what currently takes several hours to days.

Raman spectroscopy detects and distinguishes neuroblastoma and related tissues in fresh and (banked) frozen specimens.

BACKGROUND: Raman spectroscopy has been shown to accurately distinguish different neural crest-derived pediatric tumors. This study tests the ability of Raman spectroscopy to accurately identify cryopreserved tissue specimens using a classification algorithm designed from fresh tumor data and vice versa. METHODS: Fresh specimens of neuroblastoma and other pediatric neural crest tumors were analyzed with Raman spectroscopy. After analysis, the specimens were stored at -80 degrees C. At a later date, the specimens were thawed and reanalyzed by Raman spectroscopy. A computer algorithm was used to classify the spectra from the frozen tissue against a computer model built on the fresh tissue data. This classification process was then reversed, testing fresh spectra against a model built from frozen data. RESULTS: We collected 1114 spectra (862 fresh and 252 frozen) from 62 tissue samples, including 8 normal adrenal glands, 29 neuroblastomas, 14 ganglioneuromas, 8 nerve sheath tumors, and 3 pheochromocytomas. At the tissue level, frozen neuroblastoma, ganglioneuroma, nerve sheath tumor, and pheochromocytoma were distinguished from normal adrenal tissue with 100% sensitivity and specificity. Fresh tissue had the same results except for the misclassification of one specimen of nerve sheath tumor. CONCLUSIONS: The representative spectra show a high correlation between fresh and frozen tissue, and a clear difference between pathologic conditions. Spectra from frozen tissue can be accurately classified against spectra from fresh tissue and vice versa. This modality makes it possible to determine in a few minutes a result that often takes 12 to 36 hours for tissue processing and consideration by a trained pathologist to achieve.