Direct anterior approach improves in-hospital mobility following hemiarthroplasty for femoral neck fracture treatment.

INTRODUCTION: In elderly patients, an established treatment for femoral neck fractures is hip hemiarthroplasty (HHA) using the anterolateral approach (ALA). Early postoperative mobilization is crucial to reduce perioperative complications. The direct anterior approach (DAA) has been reported to facilitate early recovery of ambulation and is increasingly popular in elective hip surgery but rarely used in femoral neck fractures. The aim was to compare the outcome of the DAA and the ALA in patients treated for femoral neck fracture. MATERIALS AND METHODS: All HHAs with complete data sets were reviewed from a tertiary public healthcare institution (2013-2020). Propensity score matching was applied to compensate for possible confounders; outcome parameters were perioperative blood loss, postoperative mobility and pain. Secondary outcomes were duration of surgery, length of stay (LOS), complications, reoperation and mortality rates. RESULTS: There were 237 patients (mean age 85.8 years) available for analysis. The DAA group mobilized earlier during hospitalization (outside patient room: 50.6 vs 38.6%, p = 0.01; walking on crutches/walker: 48.1 vs 36.1%, p < 0.01), had shorter surgeries (DAA vs ALA: 72.5 vs 89.5 min, p < 0.001) and a trend towards fewer complications (32.9% vs 44.9%, p = 0.076). Blood loss (286 vs 287 ml), LOS (10.4 vs 9.5 days), pain (cessation of opioid medication: 2.9 vs 3.3 days post-op), revision (2.5 vs 3.2%) or mortality (30-days: 7.6 vs 5.7%) did not differ between patient groups. CONCLUSIONS: DAA for HHA led to earlier in-hospital mobility, shorter surgeries and a tendency towards fewer complications. No advantage was found regarding perioperative blood loss and pain.

[The throwing shoulder]. / Die Werferschulter.

BACKGROUND: During the throwing motion high forces are placed on the athlete's shoulder and extreme positions of external rotation and abduction are reached. The dynamic and static stabilizers of the glenohumeral joint need to handle a delicate balance between shoulder mobility and stability. CAUSES OF INJURY: Repetitive forces lead to adaptive osseous, capsular, ligament and muscular changes. This should increase external rotation of the shoulder and thus initially help to improve performance but ultimately could cause shoulder pathologies. For instance, tissue overuse can result in muscular imbalance, functional instability and posterior capsular contracture with the development of a glenohumeral internal rotation deficit. INJURY PATTERNS: An internal impingement is often observed in throwing athletes which can be subdivided into the more common posterosuperior type and the rarer anterosuperior type. Typical lesions in the throwing shoulder are articular-sided partial rotator cuff tears, labrum and biceps tendon lesions and edema, cysts or osteochondral lesions of the humeral head or glenoid. DIAGNOSTICS: For an accurate diagnosis it is important to include the history, a thorough physical examination and magnetic resonance arthrography. The correlation of clinical examination and imaging is critical to identify symptomatic lesions. THERAPY: If conservative therapy fails or in cases of significant structural damage resulting in clinical symptoms, surgical treatment should be considered based on the underlying pathology and carried out using established techniques and criteria.

Serum leptin levels in children and adolescents with spinal muscular atrophy types 2 and 3✰.

AIM: It has been reported that in patients with spinal muscular atrophy (SMA), lower levels of motor function are associated with hyperleptinemia. Additionally, hyperleptinemia has been found to be more frequent in underweight SMA patients. Therefore, we aimed to analyze serum leptin levels in patients with SMA. METHOD: This was a cross-sectional study of pediatric patients (2-19 years old) with SMA types 2 and 3. The investigations included anthropometric measurements, assessment of pubertal status, motor function evaluation using the Hammersmith Functional Motor Scale - Expanded (HFMSE), and serum leptin levels. RESULTS: In total, 37 patients (22 with type 2 and 15 with type 3 SMA) were included in the study. The male-to-female ratio was 1:1.3 and 62.2% of patients were prepubertal. No statistically significant correlation was found between the HFMSE score and leptin levels, rs(35) = 0.24, p = 0.15. There was, however, a strong positive relationship between the body mass index (BMI) z-score and leptin levels, rs(35) = 0.87, p < 0.001. CONCLUSION: Serum leptin levels do not seem to be a useful marker of disease severity in children and adolescents with types 2 and 3 SMA. As in the general pediatric population, leptin levels are strongly correlated with BMI, which is a surrogate measure of body fat.

Interaction ruling animal collective behavior depends on topological rather than metric distance: evidence from a field study.

Numerical models indicate that collective animal behavior may emerge from simple local rules of interaction among the individuals. However, very little is known about the nature of such interaction, so that models and theories mostly rely on aprioristic assumptions. By reconstructing the three-dimensional positions of individual birds in airborne flocks of a few thousand members, we show that the interaction does not depend on the metric distance, as most current models and theories assume, but rather on the topological distance. In fact, we discovered that each bird interacts on average with a fixed number of neighbors (six to seven), rather than with all neighbors within a fixed metric distance. We argue that a topological interaction is indispensable to maintain a flock's cohesion against the large density changes caused by external perturbations, typically predation. We support this hypothesis by numerical simulations, showing that a topological interaction grants significantly higher cohesion of the aggregation compared with a standard metric one.

A new radiographic method of measuring carpal collapse.

We assessed carpal collapse by measuring the capitate-radius (CR) distance on standard plain radiographs. This new method required validation of diagnostic accuracy, so we compared it with the method of Nattrass et al known as revised carpal height (RCH). We studied wrist radiographs from 16 normal subjects and 11 patients with unilateral Kienböck's disease. We found that there was a significant difference in the left/right CR index between the normal wrists and those with Kienbock's disease (p < 0.001). The use of left/right RCH index showed no significant difference (p = 0.30). Diagnostic accuracy was shown to be higher for the CR index using ROC curves. We then assessed 40 normal wrists and found the mean CR index to be 0.999 +/- 0.034, and suggest that values less than 0.92 are abnormal. The CR index can be used for diagnosis in unilateral carpal collapse, and for monitoring progress where the condition is bilateral.

Osteotomy for deformity of the radius. Computer-assisted three-dimensional modelling.

A computer-assisted method of preoperative planning was used to create virtual models of the deformed distal end of the radius after malunion of a fracture. By comparison with a similar model of the uninjured wrist, values were calculated for the angles and lengths to be corrected by osteotomy. Shifts of the distal fragment were analysed for 33 deformed wrists, 27 of which underwent corrective osteotomy and bone grafting. In more than half the cases there was dorsal or volar shift of 3 mm or more. The accuracy of the correction was measured by comparing the three-dimensional models before and after osteotomy with the model of the normal wrist. The volar and ulnar inclination angles of the articular surface of the radius and the radial length were regularly restored to normal.

The anatomy of the palmar scaphotriquetral ligament.

The palmar ligaments of the wrist were dissected in 15 adult cadaver wrists and demonstrated by MRI in three. Ten fetal wrists (10 to 19 weeks' gestation) were studied in histological sections. The palmar scaphotriquetral ligament was found in them all. Its attachment to the triquetrum is substantial but that to the scaphoid is thin and fan-shaped, its fibres interdigitating with those of the radioscaphocapitate ligament. The contribution of the ligament to carpal stability has yet to be studied, but it may help to support the head of the capitate when the wrist is dorsiflexed.

Physical equilibrium of the normal wrist and its relation to clinically defined "instability".

The rotational stability of the proximal carpal row was tested on six unembalmed human cadaver hand specimens. The physiological load conditions were stimulated by loading the wrist flexor and extensor tendons. Pure torque was introduced to the lunate, scaphoid and triquetrum, one at a time, by means of a dynamometer wrench, forcing the bones loaded to perform a flexion-extension motion. A truly stable state of equilibrium could be found in the normal wrist only under axial load. A uni-directional coupling was observed through the scapho-lunate ligament as a counteraction to a tendency for the lunate to extend and the scaphoid to flex. The triquetrum and lunate moved together, showing close coupling in both directions. As conclusion: a stable wrist can be defined as one which, while being loaded within a physiological range of stress, does not deviate from a stable state of equilibrium (the ability to return to a single position when disturbed) at any point within the whole physiological range of motion.

A new technique of reattachment after traumatic avulsion of the TFCC at its ulnar insertion.

One female and seven male patients (median age 25.5) presented with traumatic avulsion of the triangular fibrocartilage complex (TFCC), type 1B according to Palmer's classification. Reattachment of the TFCC near its anchoring point was combined with an intraarticular shortening osteotomy of the ulnar head. This provides an excellent approach to the TFCC and a well vascularized anchoring surface. The mooring point is biomechanically appropriate and the tissues with the best biomechanical properties are used. The functional results with a mean follow-up of 3 years were encouraging, as demonstrated by the significant improvement of pain (P = 0.017). All patients were able to return to their previous occupation; no further surgery was necessary to the distal radio-ulnar joint and no impairment of pronation and supination was detected. The final wrist score reflects the subjective results defined by the patient. However the correlation is not linear and the wrist scores are superior to the degree of satisfaction defined by the patient.

Kinematic analysis of relative motion within the proximal carpal row.

The motions of the scaphoid and triquetrum relative to the lunate have been studied on cadaver specimens. The helical axis concept was applied. The wrist motions performed were flexion-extension and radial-ulnar deviation. The results showed increased relative motion of the scaphoid towards terminal extension, and to a lesser amount in the case of the triquetrum, towards terminal flexion. The lunate might be considered as a keystone in the proximal carpal row when wrist stability is considered. It is doubly intercalated: longitudinally and transversely. Wrist ligaments co-ordinate the positioning of the bones in the mid-range of carpal motions, and restrict further motion in extreme positions of the wrist joint.

Reliability of different methods of determination of radial shortening. Influence of ulnar and palmar tilt.

Assessment of the grade of deformity after fracture of the distal end of the radius demands and accurate method of determination of radial shortening. Radiographs of 50 patients with malunited Colles' fractures were analyzed in order to find the method which is least affected by changes in ulnar and palmar tilt. Two new landmarks, the centre-point in the distal articular surface of the radius and the capitate vertex, are introduced as possible new landmarks for radial shortening determination. Results derived from commonly used methods and the new method are compared and analyzed. These show that radial shortening measured according to the commonly used landmarks is greatly affected by changes in ulnar and palmar tilt, leading to errors. Shortening measured by the two new landmarks gives results that are less influenced by rotation of the distal fragment in the frontal and sagittal planes.

Computer-assisted preoperative planning (CAPP) in orthopaedic surgery.

Computer-assisted preoperative planning (CAPP) is a complex approach to planning a surgical treatment. It includes computer-assisted design (CAD) principles, expert knowledge utilization and facilities for decision making process support. The CAPP system uses actual patient data and calculates instructions in real dimensions for performing a particular operation on a particular patient. Our first CAPP application was preoperative planning of corrective osteotomy of a malunited fracture at the distal end of the radius. The application was based on the construction of three-dimensional wire models from only two orthogonal projections of objects (two orthogonal X-rays of affected and healthy wrists). On these wire models, an operation of the affected hand was simulated until the best fitting of the models was achieved. The use of real dimensions in computer calculation was crucial because the numerical output was used as a surgical treatment guideline. The results obtained in a group of 33 patients were excellent when compared with the results reported in the literature.

Wrist arthroscopy: a prospective analysis of 53 post-traumatic carpal injuries.

We carried out a prospective study of 53 consecutive patients who had sustained a serious wrist injury. Patients who presented with a previous condition or who had undergone surgery to the wrist were excluded. History, clinical findings, standard radiographs and arthrography were correlated with the uninjured side and with arthroscopic findings. The radiolunate (RL) angle of the injured wrist differed significantly from that of the "normal" wrist (p = 0.088). POssible correlations within the whole group were studied by multivariate analysis, particularly k-means clustering, a procedure which enables the detection of natural groups. We found that ligamentous tears at the triquetrum in the midcarpal joint significantly (p = 0.004) affected the equilibrium of the proximal row defined by clustering with the RL and scapholunate (SL) angles. The use of multivariate analysis techniques in combination with cross tabulation for the surgery of intracarpal ligamentous abnormalities seen at arthroscopy might help us to define better the function of the ligaments of the wrist. These findings, of little help in daily practice, might be important for clinical research.

The value of arthroscopy in the evaluation of carpal instability.

In a prospective study, arthroscopic examinations were performed on 42 wrists following injury. Clinical findings, radiology, and arthrography were compared to the arthroscopic findings. Only obvious or total ligamentous ruptures found on arthroscopy were considered in the analysis. No direct correlation could be demonstrated with clinical findings or arthrography. The distribution pattern of ligament injury involving the radial and ulnar compartment of the wrist joint in 40% of the cases suggests that carpal dysfunction following injury and ligamentous tears is a more complex problem than usually accepted. The ulnar midcarpal joint seems more prone to injury than the radiocarpal portion of the wrist. This suggests an important biomechanical function of the palmar ligaments inserting on the triquetrum.

Sleep-waking cycle disturbance in patients with obstructive sleep apnea syndrome.

Eighteen (18) obese patients with clinically confirmed obstructive sleep apnea syndrome (OSAS) and five (5) obese persons with no apnea crises noticed during sleep apart from occassional loud snoring, have been polysomnographically assessed. The obtained results show that the patients with apnea syndrome sleep very badly, and consequently, shortened sleep latency and frequent body movements, along with apneas, are regarded as the leading polysomnographic symptoms. Vigilance profile during sleep, that is, interchange and frequency of each of sleep stages (I, II, III, IV, REM) are similar in both tested groups. The suppression of restitutive stages of sleep (III, IV, REM) is considered to be a dominant characteristic of vigilance during sleep in obese persons and obese persons with manifest apnea syndrome. Relatively prolonged sleep latency in obese persons without manifest apnea syndrome indicates, however, restitutively higher quality of their nocturnal sleep. Contrary to the patients with apnea syndrome, they do not suffer from excessive evening somnolence, so that their daily alertness and sleep vigilance during night are of a better quality, although the lack of deep and REM sleep is observed in them as well.

[Resection, interposition and suspension arthroplasty for treatment of Basal joint arthritis of the thumb: a randomized and prospective comparison of techniques using the abductor pollicis longus- and the flexor carpi radialis tendon]. / Ein randomisierter prospektiver Vergleich der Verwendung der Abduktor pollicis longus-Sehne und der Flexor carpi radialis-Sehne bei der Resektions-Suspensions-Interpositions-Arthroplastik in der operativen Therapie der Rhizarthrose.

The operative treatment of thumb carpometacarpal joint arthritis may include resection-suspension-interposition-arthroplasty. Although quite a technically demanding procedure, a suspension arthroplasty using a strip of the flexor carpi radialis tendon is quite a popular technique. Other techniques, which use the abductor pollicis longus (APL) tendon, is also widely accepted.The aim of this randomized, prospective study was to compare the results of these 2 procedures 8 months postoperatively.From May 2005 to December 2006 a total of 55 operations in 53 patients with symptomatic Grade III or IV 1st CMC joint arthritis were identified and recruited into the study. They were then randomized to one of the 2 groups (APL vs. FCR). Patients were assessed preoperatively, and then immediately and 8 months postoperatively. Both, subjective parameters (Visual Analog Scale and DASH-Score) and functional parameters (maximum radial abduction, opposition and pinch- and key grip strength) where recorded. Additionally, the trapezial space was assessed radiographically postoperatively.After 8 months both groups had comparable subjective results (APL-group: VAS 2.3 points, DASH 24 points; FCR-group: VAS 1.9 points, DASH 20 points) as well as functional results (APL-group: radial abduction 55.3°, key-grip strength 8.1 kg, pinch-grip strength 5.5 kg; FCR-group: radial abduction 55.8°, key-grip strength 7.2 kg, pinch-grip strength 4.7 kg). Radiologically both groups showed an approximate 50% reduction in the height of the trapezial space.In resection-suspension-interposition-arthroplasty of the 1st CMC joint, similar results can be obtained using the technically less demanding APL-procedure when compared with the FCR-technique 8 months postoperatively.

[Late reconstruction of distal biceps tendon rupture with fascia lata graft and Mitek anchors]. / Spätrekonstruktion der distalen Bizepssehnenruptur mit Fasci-lata-Graft und Mitek-Ankern.

Ruptures of the distal biceps tendon are rare but well documented. A technique for reinserting the distal biceps tendon into the radial tuberosity with two Mitek anchors and a fascia lata graft is presented and illustrated by a case report. Ectopic ossification as a complication after the procedure is discussed as well as the final outcome. It could be concluded that late reconstruction of the distal biceps tendon rupture with fascia lata and Mitek anchors is a safe procedure that can be advocated in a restricted number of cases where acute injury has been overlooked.

Presentation and course of Type 2 diabetes in youth in a large multi-ethnic city.

AIM: To review the clinical experience of children and teens diagnosed with Type 2 diabetes (T2DM) at a paediatric hospital serving a large urban multi-ethnic population. METHODS: Retrospective chart review of patients with T2DM followed in the diabetes clinic at the Hospital for Sick Children (HSC) over an 8-year period. Patients who were included were younger than 18, referred at the onset of diabetes, and where presentation and/or clinical course was 'typical' of T2DM. RESULTS: Of 1020 children with diabetes followed at HSC, 4% were identified as having T2DM in 2002. There was a sixfold increase in new cases from 1994 to 2002. The mean age at diagnosis was 13.5 +/- 2.2 years (range 8.8-17.5) with a female-to-male ratio of 1.7. Most had a first- or second-degree relative with T2DM. There was an overrepresentation of children with T2DM from Asian and African Canadian ethnic groups relative to the regional population. The majority of teens were asymptomatic at presentation, with a smaller number in diabetic ketoacidosis (DKA) at diagnosis. Mean HbA1c at diagnosis was 10 +/- 3.4%. Approximately one half of patients were initially treated by diet and exercise with many requiring intensification of therapy over a short period of time. CONCLUSIONS: We report a similar increase in T2DM incidence and clinical presentation at HSC to other clinic reports in large North American urban centres. Of note is the high prevalence of children of South/South-East Asian descent.

[Pathophysiology of perilunate dislocation]. / Pathophysiologie der perilunären Luxation.

The anatomy of the palmar scapho-triquetral ligament was studied: on 15 hand specimens by means of gross anatomical dissections and MR imaging; and on a further 10 foetal wrist specimens, microanatomically. This ligament allows us to present the proximal carpal row as a socket, consisting of an upper part (the triquetrum, distal part of the scaphoid, and the dorsal and palmar scapho-triquetral ligament), and a base (the concave parts of the lunatum and scaphoid, connected by the scapho-lunate ligament). With a hyperextension wrist injury the upper part follows the distal part of the carpus, while the base remains fixed at the radius. The upper part slips away from the base, consequently, injuring the ligamentous structure, or causing a scaphoid fracture. The luno-triquetral and the palmar scapho-triquetral ligaments are also frequently torn. The overall prognosis depends on the grade of ligament damage. The arthroscopy allows us to estimate the state of the ligament structures, therefore, it is indicated before any reconstructive operation.

Kinematics of the wrist and its ligaments.

Precise anatomic dissections of unembalmed physiologically intact cadaver specimens were carried out before proceeding with the kinematic investigations on further specimens. Carpal flexor and extensor tendons were used to move the wrist. The analysis of the carpal bone movements was performed according to the finite helical axis motion concept for increments of 10 degrees for each main carpal motion. Separate axes of rotation for each of the bones in the proximal carpal row were found; however, the axes for the lunate and triquetrum bones were close, and the magnitudes of rotation and translation almost equal. One finding was that the axes of rotation of the bones in the proximal carpal row often cross at some particular point. Because the axes of the scaphoid are differently oriented than those of the lunate and triquetrum, shear might occur during wrist motion. This indicates also that the scaphoid and lunate cannot be considered rigidly coupled elements. We also assume that the individual bones of the proximal carpal row self-align themselves as long as they are not constrained by torsion. Several potential mechanisms of flexion motion of the proximal carpal row during radioulnar deviations of the hand were considered. The ligament function is still an unsolved problem. Compensation mechanisms may mask clear correlations between a lesion and the instability pattern associated with it. The proximal carpal row should be studied as one system.