The IDeaS initiative: pilot study to assess the impact of rare diseases on patients and healthcare systems.

BACKGROUND: Rare diseases (RD) are a diverse collection of more than 7-10,000 different disorders, most of which affect a small number of people per disease. Because of their rarity and fragmentation of patients across thousands of different disorders, the medical needs of RD patients are not well recognized or quantified in healthcare systems (HCS). METHODOLOGY: We performed a pilot IDeaS study, where we attempted to quantify the number of RD patients and the direct medical costs of 14 representative RD within 4 different HCS databases and performed a preliminary analysis of the diagnostic journey for selected RD patients. RESULTS: The overall findings were notable for: (1) RD patients are difficult to quantify in HCS using ICD coding search criteria, which likely results in under-counting and under-estimation of their true impact to HCS; (2) per patient direct medical costs of RD are high, estimated to be around three-fivefold higher than age-matched controls; and (3) preliminary evidence shows that diagnostic journeys are likely prolonged in many patients, and may result in progressive, irreversible, and costly complications of their disease CONCLUSIONS: The results of this small pilot suggest that RD have high medical burdens to patients and HCS, and collectively represent a major impact to the public health. Machine-learning strategies applied to HCS databases and medical records using sentinel disease and patient characteristics may hold promise for faster and more accurate diagnosis for many RD patients and should be explored to help address the high unmet medical needs of RD patients.

Outerbridge Grade IV Cartilage Lesions in the Hip Identified at Arthroscopy.

PURPOSE: To determine factors associated with grade IV cartilage defects in the hip in patients undergoing hip arthroscopy with joint pain. METHODS: Data from consecutive patients who underwent hip arthroscopy performed by a single surgeon over a period of 4 years were included in this study. The study group included 1,097 patients (491 women and 606 men; mean age, 37 years) who underwent hip arthroscopy for pain, had no prior hip surgery, and were aged 18 years or older. Preoperative radiographs, patient demographic characteristics, and operative details were used to identify risk factors for cartilage defects. RESULTS: Grade IV chondral defects were present in 308 of 1,097 hips (28%). Isolated chondral lesions were more frequently observed on the acetabulum (76%) than on the femoral head (24%). Defects of the acetabulum were more commonly anterosuperior (94.7%) and less commonly posterolateral (5.3%). Patients with less than 2 mm of joint space on preoperative radiographs were 8 times more likely to have a grade IV lesion than those with more than 2 mm. Men were more likely than women to have grade IV lesions (35% v 19%, P = .0001); patients with grade IV lesions were older than those without (42 years v 34 years, P = .0001). Hips with grade IV lesions had significantly higher alpha angles than those without (74° v 70°, P = .0001). Patients with grade IV defects reported a longer duration of symptoms than those without (37 months v 27 months, P = .007). Independent risk factors for the presence of grade IV chondral defects were less than 2 mm of joint space, male gender, increasing age, larger alpha angle, and longer duration of symptoms. CONCLUSIONS: Grade IV chondral defects in patients undergoing hip arthroscopy were associated with decreased joint space, increased time from symptom onset to arthroscopy, male gender, and larger alpha angles associated with femoroacetabular impingement. LEVEL OF EVIDENCE: Level IV, prognostic case series.

Interobserver and intraobserver reliability of the Walch classification in primary glenohumeral arthritis.

INTRODUCTION: In 1999, Walch et al introduced a novel classification scheme for glenoid morphology in patients with primary glenohumeral arthritis and reported substantial intraobserver and interobserver reliability. This classification system has been widely used by shoulder surgeons but a recent independent evaluation revealed considerable lower agreement. The goal of this study was to evaluate the reproducibility of the Walch classification. MATERIAL AND METHODS: Twenty-three consecutive patients (26 shoulders) undergoing total shoulder arthroplasty (TSA) or evaluated for TSA between March 2007 and November 2007 had shoulder CT scans performed and were included in this study. Three attending shoulder surgeons and 5 shoulder/sports medicine trained fellows independently and blindly evaluated CT scans of 26 consecutive patients with primary glenohumeral arthritis, and classified each patient according to the Walch classification to determine the interobserver reliability. The intraobserver reliability was assessed by comparison of the classification of each patient by the observers on 2 occasions separated by at least 6 weeks. RESULTS: The overall interobserver agreement for all 8 observers was moderate (k=.508) for all Walch classes. The overall intraobserver reproducibility was substantial (k=.611). DISCUSSION: We have shown that the interobserver reliability of the Walch classification is moderate while the intraobserver reliability is substantial. This is similar to or superior to the reliability of many commonly used orthopaedic classification systems. While the Walch classification system is not as reliable as initially suggested and improvement of this classification system would be of utility for future clinical studies, we have shown that this is an acceptable classification system and has good clinical and research applications.

Central cord syndrome.

Central cord syndrome is the most common type of incomplete spinal cord injury. This syndrome most often occurs in older persons with underlying cervical spondylosis caused by a hyperextension mechanism. It also occurs in younger persons who sustain trauma to the cervical spine and, less commonly, as a result of nontraumatic causes. The upper extremities are more affected than the lower extremities, with motor function more severely impaired than sensory function. Central cord syndrome presents a spectrum, from weakness limited to the hands and forearms with sensory preservation, to compete quadriparesis with sacral sparing as the only evidence of incomplete spinal cord injury. Historically, treatment has been nonsurgical, but recovery is often incomplete. Early surgical treatment of central cord syndrome remains controversial. However, recent studies have shown benefits, particularly of early surgery to decompress the spinal cord in patients with pathologic conditions revealed by radiography or MRI.

Simulation of surgical glenoid resurfacing using three-dimensional computed tomography of the arthritic glenohumeral joint: the amount of glenoid retroversion that can be corrected.

HYPOTHESIS: The magnitude of glenoid retroversion that can be surgically corrected in total shoulder arthroplasty and still enable implantation of a glenoid component has not been established. We hypothesized that increased retroversion will require smaller glenoid components for successful implantation when the glenoid is surgically corrected and that correction beyond 20 degrees of retroversion is not feasible without peg penetration. METHODS: Using 3-dimensional models created from computed tomography of 19 patients with advanced shoulder osteoarthritis, we simulated glenoid resurfacing on varying degrees of retroverted, osteoarthritic glenoids using an in-line 3-peg glenoid component and asymmetric reaming to correct version. RESULTS: Glenoids with preoperative retroversion of less than 12 degrees could always be implanted with 46-mm and 52-mm glenoid components at neutral version without vault violation. Conversely, glenoids with greater than 18 degrees of preoperative retroversion could not be implanted at neutral version due to vault violation from the pegs. The average preoperative glenoid retroversion of patients in which a 46-mm glenoid was implanted at neutral version was 8.9 degrees +/- 6.4 degrees compared with 19.0 degrees +/- 7.1 degrees for those that could not be implanted at neutral (P = .005). DISCUSSION: Computer-aided surgical simulation shows that glenoid retroversion is a critical factor in determining successful glenoid implantation. Smaller sized glenoid components allow for greater version correction and less residual postsimulation retroversion when an in-line pegged component is used.