Fast and easy preoperative estimation of cancellous bone mineral density in patients with proximal femur fractures.

INTRODUCTION: Postoperative complications after hip fractures in osteoporotic bone such as implant cutout can be reduced by the use of specially designed implants or additional cement augmentation. It is not yet clear at which degree of osteoporosis, patients will profit from implant augmentation or specially designed implants for geriatric patients. As the surgeon ideally should obtain information on local bone quality at the site of implant anchorage already preoperatively, the aim of the study was to develop an easily applicable radiographic method to estimate bone quality in those patients. MATERIALS AND METHODS: 75 patients with unilateral hip fracture were included. Preoperatively, a CT scan with a calibration device was conducted. Postoperatively, DXA scans were performed. The proposed method measures local cancellous bone mineral density in the contralateral and uninjured femoral head. As a control, 15 young and healthy non-osteoporotic subjects were included. Inter- and intraobserver reliability was investigated for a subgroup of 20 patients. RESULTS: Study group patients had a mean BMD measured by CT scans of 194.2 mg/cm(3) (SD 40.4). There was a statistically significant correlation with data from DXA scans (r = 0.706, p < 0.001). The control group was significantly younger and showed a significantly higher BMD when compared to the study group (p < 0.001). Reliability evaluation showed no statistically significant difference in inter- and intraobserver measurements. Interclass correlation proved to be very high. CONCLUSION: The proposed method is an easily applicable, reliable and useful tool to estimate bone quality preoperatively using the contralateral hip as a reference. Obtained data may facilitate the decision-making towards the use of further therapeutic measures to improve implant anchorage in osteoporotic bone such as bone cement augmentation. Thus, our method allows for a more individualized surgical treatment of hip fracture patients adapted to the estimated cancellous bone quality of the patient.

Allograft augmentation in proximal humerus fractures.

OBJECTIVE: Achieve stable fixation to initially start full range of motion (ROM) and to prevent secondary displacement in unstable fracture patterns and/or weak and osteoporotic bone. INDICATIONS: (Secondarily) displaced proximal humerus fractures (PHF) with an unstable medial hinge and substantial bony deficiency, weak/osteoporotic bone, pre-existing psychiatric illnesses or patient incompliance to obey instructions. CONTRAINDICATIONS: Open/contaminated fractures, systemic immunodeficiency, prior graft-versus-host reaction. SURGICAL TECHNIQUE: Deltopectoral approach. Identification of the rotator cuff. Disimpaction and reduction of the fracture, preparation of the situs. Graft preparation. Allografting. Fracture closure. Plate attachment. Definitive plate fixation. Radiological documentation. Postoperative shoulder fixation (sling). POSTOPERATIVE MANAGEMENT: Cryotherapy, anti-inflammatory medication on demand. Shoulder sling for comfort. Full active physical therapy as tolerated without pain. Postoperative radiographs (anteroposterior, outlet, and axial [as tolerated] views) and clinical follow-up after 6 weeks and 3, 6, and 12 months. RESULTS: Bony union and allograft incorporation in 9 of 10 noncompliant, high-risk patients (median age 63 years) after a mean follow-up of 28.5 months. The median Constant-Murley Score was 72.0 (range 45-86). Compared to the uninjured contralateral side, flexion was impaired by 13 %, abduction by 14 %, and external rotation by 15 %. Mean correction of the initial varus displacement was 38° (51° preoperatively to 13° postoperatively).

Sagittal wrist motion of carpal bones following intraarticular fractures of the distal radius.

Forty patients (mean age, 37 years) with intraarticular C2 and C3 Colles fractures were treated by open reduction, internal fixation and bone grafting. At a mean follow-up of 8 years radiocarpal and midcarpal motion was evaluated, the depth of the articular surface of the distal radius in the sagittal plane was measured and the presence of arthritis was noted. The fractures healed with a mean palmar tilt of 6 degrees , a mean ulnar tilt of 18 degrees and ulna variance within 1 mm of the contralateral side. The depth of the articular surface of the distal radius was 1.3 mm greater than the uninvolved side. Measurement of carpal bone angles relative to the radius in maximum flexion and extension revealed lunate extension of 23 degrees , lunate flexion of 15 degrees , capitate extension of 62 degrees , capitate flexion of 40 degrees . There was a significant correlation between articular surface depth and radiocarpal motion.

Outcome after primary hemiarthroplasty for fracture of the head of the humerus. A retrospective multicentre study of 167 patients.

We have examined 167 patients who had a hemiarthroplasty for three- and four-part fractures and fracture-dislocations of the head of the humerus in a multicentre study involving 12 Austrian hospitals. All patients were followed for more than a year. Anatomical healing of the tuberosity significantly influenced the outcome as measured by the Constant score and subjective patient satisfaction. With regard to pain, the outcome was generally satisfactory but only 41.9% of patients were able to flex the shoulder above 90 degrees. The age of the patient and the type of prosthesis significantly influenced the healing of the tuberosity, but bone grafting did not. Achievement of healing of the tuberosity was inferior in institutions at which less than 15 hemiarthroplasties had been performed (Mann-Witney U test, p = 0.0001).

[Late sequelae of fractures of the distal third of the forearm during the growth period]. / Spätfolgen nach Frakturen im distalen Unterarmdrittel im Wachstumsalter.

Fractures to the distal third of the forearm are the most common fractures of the upper extremity, with the majority occurring between the age of ten and 14 years. With the exception of the rare epiphyseal fractures, they have a favourable prognosis. The present study investigates the frequency and extent of potential clinical and radiological late sequelae of fractures in the distal third of the forearm during growth. Of the patients treated at the Innsbruck University Department of Traumatology from 1980 to 1992, 220 patients of a growing age with 232 closed fractures in the distal third of the forearm were followed up. The radius alone was affected in 60% of these cases; the radius and the ulna in 40%. Fractures of the ulna alone were not present. The mean age of the patients at the time of injury was nine years (range one to 16 years) and the mean time of follow-up ten years (range five to 16 years). In addition to the patient's subjective assessment, the right and left sides were compared with regard to mobility of the wrist and rotational movement of the forearm. Based on standard X-rays, the frontal (radio-ulnar) and lateral (dorso-palmar) radial joint angle as well as the difference in the radio-ulnar plane were compared with the contralateral side. Clinical and radiological findings were summarised into an overall result. 19% of the patients reported pain in the injured wrist. Mobility of the wrist in the sagittal and/or frontal plane was limited in 5% of patients and rotation of the forearm was limited in 16% of patients. A statistically significant accumulation of limited rotation was seen after physeal fractures of the ulna ("one-way" ANOVA-test, p = 0.0033). A difference between the left and right side in regard to the frontal radial joint angle was seen in 6% of patients and a difference in the lateral radial joint angle was registered in 2% of patients. A difference in the radio-ulnar plane was observed in 37% of patients. In the presence of relative ulna-plus variance, 75% of patients complained of pain in the ulnocarpal compartment of the wrist. In these patients, dynamic magnetic resonance tomography revealed a compression of the ulnocarpal disk between the proximal carpal bones and the head of the ulna, as well as degeneration in the central portion of the disk. The overall outcome was very good in 72%, good in 19%, moderate in 6% and poor in 3% of patients. The younger the children had been at the time of injury, the more favourable were the results (chi-square test, p = 0.009). Children older than ten years of age with an angulatory deformity of more than 20 degrees and/or fragment dislocation over half of the breadth of the shaft at fracture consolidation showed the poorest results. Further factors having a negative influence on the outcome were repeated reduction manoeuvres and an additional fracture of the ulna.

[Dorsal dislocation of the proximal interphalangeal joints of the finger. Results after static and functional treatment]. / Dorsale Luxation der PIP-Gelenke der Finger. Ergebnisse nach statischer und nach funktioneller Behandlung.

In a follow-up examination of 30 patients who had sustained dorsal dislocations of the PIP joint, the results of two conservative therapy regimens, either immobilisation or early motion were investigated. In Group A, 15 patients were treated by closed reduction and immobilisation with a forearm cast for four weeks. Nine patients showed normal range of motion, whereas a limitation of extension of ten degrees and more was seen in six cases. All PIP joints were stable. Nine patients were satisfied. Three patients complained of a limitation of extension, two of a limitation of extension and pain and one of swelling. In Group B, 15 patients were treated by dorsal block splinting of the PIP joint following reposition. The finger was released in extension with daily active exercise of the PIP joint. Only two of 15 patients showed limitation of extension, whereas 13 cases showed normal range of motion. Instability of one collateral ligament was seen in two cases. Palmar instability did not occur. Eleven patients were satisfied. One patient complained of instability, pain and lack of extension, one of pain in combination with instability, one of pain and one of swelling of the joint.

Lack of fifth anchoring point and violation of the insertion of the rotator cuff during antegrade humeral nailing: pitfalls in straight antegrade humeral nailing.

Antegrade nailing of proximal humeral fractures using a straight nail can damage the bony insertion of the supraspinatus tendon and may lead to varus failure of the construct. In order to establish the ideal anatomical landmarks for insertion of the nail and their clinical relevance we analysed CT scans of bilateral proximal humeri in 200 patients (mean age 45.1 years (sd 19.6; 18 to 97) without humeral fractures. The entry point of the nail was defined by the point of intersection of the anteroposterior and lateral vertical axes with the cortex of the humeral head. The critical point was defined as the intersection of the sagittal axis with the medial limit of the insertion of the supraspinatus tendon on the greater tuberosity. The region of interest, i.e. the biggest entry hole that would not encroach on the insertion of the supraspinatus tendon, was calculated setting a 3 mm minimal distance from the critical point. This identified that 38.5% of the humeral heads were categorised as 'critical types', due to morphology in which the predicted offset of the entry point would encroach on the insertion of the supraspinatus tendon that may damage the tendon and reduce the stability of fixation. We therefore emphasise the need for 'fastidious' pre-operative planning to minimise this risk.

Anatomical glenoid reconstruction via a J-bone graft for recurrent posttraumatic anterior shoulder dislocation.

OBJECTIVE: To reconstruct the anatomical glenoid shape in cases of osseous glenoid rim defects after recurrent posttraumatic anterior shoulder dislocation to restore stability without severely compromising the range of motion. INDICATIONS: Osseous glenoid defects after recurrent posttraumatic anterior shoulder dislocation. Suitable for primary stabilization as well as for revision surgery in cases previously operated on. CONTRAINDICATIONS: Recurrent anterior shoulder dislocations without glenoid rim defects. Hyperlax shoulders with multidirectional instability. Patients over 60 years of age due to compromised bone quality. Teenage patients due to incomplete apophyseal fusion at the iliac crest. SURGICAL TECHNIQUE: The subscapularis tendon and capsule are split. The humeral head is retracted laterally, and the glenoid defect is prepared and abraded with a rasp. A bicortical iliac crest bone block including crest and outer cortex is harvested and molded in a J-shaped manner. To incorporate the graft, a crevice on the glenoid rim is produced using a chisel. The keel is fitted into the preformed crevice with a spiked impactor. The graft's surface is contoured using a high-speed burr. RESULTS: A total of 47 shoulders were followed-up after an average of 90 months (range 25-152 months). The mean Rowe scores were 94.3 for the affected shoulder and 96.8 for the uninjured shoulder. The Constant scores reached 93.5 and 95 points, respectively. Loss of external rotation was 4.4°. In addition, 24 shoulders were followed-up by computed tomography (CT). There were no recurrences, with the exception of one traumatic graft fracture. Of 19 patients with arthropathy at follow-up, 11 already had arthropathy prior to the procedure.

The medial periosteal hinge, a key structure in fractures of the proximal humerus: a biomechanical cadaver study of its mechanical properties.

The medial periosteal hinge plays a key role in fractures of the head of the humerus, offering mechanical support during and after reduction and maintaining perfusion of the head by the vessels in the posteromedial periosteum. We have investigated the biomechanical properties of the medial periosteum in fractures of the proximal humerus using a standard model in 20 fresh-frozen cadaver specimens comparable in age, gender and bone mineral density. After creating the fracture, we displaced the humeral head medial or lateral to the shaft with controlled force until complete disruption of the posteromedial periosteum was recorded. As the quality of periosteum might be affected by age and bone quality, the results were correlated with the age and the local bone mineral density of the specimens measured with quantitative CT. Periosteal rupture started at a mean displacement of 2.96 mm (SD 2.92) with a mean load of 100.9 N (SD 47.1). The mean maximum load of 111.4 N (SD 42.5) was reached at a mean displacement of 4.9 mm (SD 4.2). The periosteum was completely ruptured at a mean displacement of 34.4 mm (SD 11.1). There was no significant difference in the mean distance to complete rupture for medial (mean 35.8 mm (SD 13.8)) or lateral (mean 33.0 mm (SD 8.2)) displacement (p = 0.589). The mean bone mineral density was 0.111 g/cm(3) (SD 0.035). A statistically significant but low correlation between bone mineral density and the maximum load uptake (r = 0.475, p = 0.034) was observed. This study showed that the posteromedial hinge is a mechanical structure capable of providing support for percutaneous reduction and stabilisation of a fracture by ligamentotaxis. Periosteal rupture started at a mean of about 3 mm and was completed by a mean displacement of just under 35 mm. The microvascular situation of the rupturing periosteum cannot be investigated with the current model.

Proximal humeral fractures: what is semi-rigid? Biomechanical properties of semi-rigid implants, a biomechanical cadaver based evaluation.

INTRODUCTION: Proximal humerus fractures remain challenging especially in the elderly. Biomechanical data put semi-rigid implants in favour of osteopenic or osteoporotic situation. Little surgical side damage is associated with a minimal invasive approach of these implants. The aim of this study was to evaluate the mechanical properties of three such implants. MATERIAL AND METHODS: Fresh frozen cadaver specimens were mounted as proposed by the distributors. Three different implants were used: LCP-PH (locking compression plate proximal humerus, Synthes, Austria), HB (humerus block, Synthes, Austria), and IMC (intramedullary claw, ITS, Austria). Subcapital fracture was simulated by resecting a 5 mm gap. All specimens were comparable in "B" (one), "M" (ineral) and "D" (ensity). Four load cases were tested: varus bending, medial shearing and axial torque. A cyclic test (1,000 cycles) was performed in the first load case (varus stress) for all three implants. RESULTS: The LCP-PH was the most rigid in all three load cases, always followed by the HB. The IMC was the most elastic device with almost immeasurable values in axial torque. In the cyclic setting, the load reduction of the HB followed by the LCP-PH was significantly better than that for the IMC. CONCLUSION: The differences in stiffness are varying tremendously. The IMC is the implant with the lowest stiffness in all load cases and the highest load reduction. New "semi-rigids" claim good clinical performance, yet prospective clinical studies have to prove this. It is unlikely that the IMC can maintain fracture reduction in fracture situations of complex nature (no ligamentotaxis).

Bifocal disruption of the knee extensor apparatus ("floating patella") in a 13-year-old patient.

We present the unusual case of a traumatic "floating patella" in a 13-year-old healthy boy. No predisposing factors were diagnosed. The obvious bony avulsion was treated by immediate open reduction and screwing, whereas the quadriceps tendon rupture was missed diagnostically in the first step. During the course of the treatment, the extension lag lead to the delayed diagnosis of the concomitant rupture of the quadriceps tendon. After the surgical treatment of the latter, the patient healed with full function of the extensor apparatus and full ROM. Bifocal injury of the knee extensor apparatus is therefore possible in young adolescents without presenting the predisposing factors and should thus be considered.

[Comparison of open versus percutaneous treatment for humeral head fracture]. / Vergleich der offenen vs. perkutanen Versorgung der Oberarmkopffraktur.

BACKGROUND: The hypothesis of this study was that percutaneous techniques lower the risk of post-traumatic avascular necrosis. MATERIALS AND METHODS: In this retrospective study 83 patients were followed up clinically and radiologically for signs of avascular necrosis and nonunion after open or percutaneous treatment of proximal humerus fractures. Mean age was 50 years. Fractures were classified in 22 patients (26.5%) as two part, in 21 patients (25.3%) as three part, in 39 patients (47%) as four part, and in 1 patient (1.2%) as fracture dislocation (Neer classification). Fractures were treated in 12 patients (14.5%) by ORIF (open reduction and internal fixation) and in 71 patients (85.5%) by CRPF (closed reduction and percutaneous fixation). Both groups were statistically equally distributed according to fracture type (Mann-Whitney U, p=0.267) and age (One-way-Annova, p=0.740). The postoperative regime did not differ between the two groups. RESULTS: Patients suffered significantly more avascular necrosis after open treatment [five patients (50%) versus eight patients (12.7%) in the percutaneous group, Mann-Whitney, p=0.004]. The risk for avascular necrosis and nonunion increased with age. Mean age of patients with avascular necrosis was 57 years, and the age of patients with nonunion was 67 years. CONCLUSION: Percutaneous treatment of humeral head fractures seems to be a reliable method for lowering the risk of avascular necrosis in young patients.

Anatomical considerations regarding the "bare spot" of the glenoid cavity.

The "bare spot" of the glenoid cavity has recently been described as a constant reference point to quantify the amount of bone loss from the inferior portion of the glenoid cavity. In shoulder surgery this spot should help the surgeon to determine the width of the inferior portion of the glenoid cavity arthroscopically. The aim of this study was to determine the localization of the bare spot within the glenoid cavity and to prove its usefulness in shoulder surgery by means of a macroscopic study using embalmed glenohumeral joints ( n=20; 12 left, 8 right). Each glenoid cavity was photographed and transferred to a commercial AutoCAD software program. The bare spot was marked and the mean distances between the center of the bare spot and the inferior ( a), anterior ( b(1)) and posterior ( b(2)) inner margins of the glenoid labrum as well as its relationship ( c) to the mid-point of a virtual circle formed by the inferior portion of the glenoid cavity were measured (mean values : a=9.70, b(1)=10.88, b(2)=13.71, c=3.2 mm). In most cases, the bare spot showed a significantly excentric position within the inferior part of the glenoid cavity ( p<0.05). Due to the great variability in the shape of the glenoid cavity, an inferior circle according to previous descriptions could only be observed in half the specimens. From the results of our study the bare spot seems to be an unreliable landmark for the determination of the center of the inferior portion of the glenoid cavity, although it has a constant appearance and is probably expressed as the result of cartilaginous distribution due to dynamic shoulder activity.

Dorsal scapholunate ligament reconstruction using a periosteal flap of the iliac crest.

INTRODUCTION: To report a new technique for scapholunate ligament reconstruction, using a periosteal flap of the iliac crest. MATERIALS AND METHODS: In 12 patients with static SL instability, a periosteal flap was harvested from the anterior portion of the iliac crest. Following repositioning of the carpals, the flap was fixed to the scaphoid and lunate between an incompletely osteotomised scale at the dorsal horn of the scaphoid and lunate. Pin fixation of the scapholunate (SL) and CL interval secured postoperative reduction for 8 weeks. A forearm plaster cast was worn for 12 weeks. RESULTS: Eleven patients, all male, were available for follow-up at an average of 29 months. The interval between trauma and surgery averaged 15 months. The preoperative SL angle measured 77 deg, CL angle was -10 deg, and SL gap amounted to 5.2 mm. At follow-up, SL angle was 59 deg, CL angle measured -2 deg, and SL gap was 2.1 mm. SL gap, SL angle, and CL angle improved significantly from preoperative to follow-up values. According to the clinical grading system of Green and O'Brian, 6 patients scored in the excellent and good category and 5 in the fair category. Using the radiologic grading system of Gickel and Millender, 9 patients scored as excellent and good, whereas the 2 poor results were due to failure of the technique. CONCLUSION: The technique enables reduction of the SL angle and SL gap in patients with static reducible scapholunate instability. The initial results are quite encouraging.