Mika P. Koivikko

Factors associated with nonunion in conservatively-treated type-II fractures of the odontoid process

In type-II fractures of the odontoid process, the treatment is either conservative in a halo vest or primary surgical stabilisation. Since nonunion, requiring prolonged immobilisation or late surgery, is common in patients treated in a halo vest, the identification of those in whom this treatment is likely to fail is important. We reviewed the data of 69 patients with acute type-II fractures of the odontoid process treated in a halo vest. The mean follow-up was 12 months. Conservative treatment was successful, resulting in bony union in 32 (46%) patients. Anterior dislocation, gender and age were unrelated to nonunion. However, nonunion did correlate with a fracture gap (> 1 mm), posterior displacement (> 5 mm), delayed start of treatment (> 4 days) and posterior redisplacement (> 2 mm). We conclude that patients presenting with these risk factors are unlikely to achieve bony union by treatment in a halo vest. They deserve careful attention during the follow-up period and should also be considered as candidates for primary surgical stabilisation.

Conservative and operative treatment in cervical burst fractures

Abstract The aim of this study is to compare the results of non-operative and anterior operative treatment of cervical burst and flexion teardrop fractures. Sixty-nine consecutive patients treated during 1980 to 1995 were reviewed retrospectively. Thirty-four of them had been treated with skull traction or halo-vest and 35 with anterior decompression, bone grafting and fixation by an anterior Caspar plate. Neurological functioning on admission and at the end of the follow-up was assessed by using Frankel’s classification. Kyphosis and spinal canal encroachment by retropulsed fragments were measured radiographically. Operatively treated patients recovered more often with at least one Frankel grade (P = 0.027) and presented less narrowing of the spinal canal (P = 0.0006) and kyphotic deformity (P = 0.00003) at the end of the follow-up. In comparison with the conservative methods, the operative Caspar technique provided superior decompression and fixation as well as promoted the healing of cord injuries caused by burst and flexion teardrop fractures.

Shoulder Magnetic Resonance Arthrography: A Prospective Randomized Study of Anterior and Posterior Ultrasonography-Guided Contrast Injections

Background: Magnetic resonance (MR) arthrography is an accurate imaging method for internal shoulder derangements and rotator cuff pathologies. Both anterior and posterior contrast injection techniques, under palpatory, fluoroscopic, or ultrasonographic guidance have been described in the literature. However, clinical comparisons of the injection techniques remain few. Purpose: To compare the performance of anterior and posterior ultrasonography (US)-guided arthrography injections of the shoulder regarding patient discomfort and influence on diagnostic MR reading, and to illustrate the typical artifacts resulting from contrast leakage in the respective techniques. Material and Methods: 43 MR arthrographies were prospectively randomized into anterior and posterior US-guided contrast injections and performed by two radiologists, with the study of artifacts from contrast leakage. Pain from the injections was assessed by a survey utilizing a 100-mm visual analogue scale (VAS). Results: Of the 23 anterior injections, nine caused contrast artifacts in the subscapular tendon, and in three the leakage extended further anteriorly. Of the 20 posterior injections, 12 showed injection artifacts of the rotator cuff, extending outside the cuff in seven. Two of the anterior and none of the posterior artifacts compromised diagnostic quality. In posterior injections, the leakage regularly occurred at the caudal edge of the infraspinatus muscle and was easily distinguishable from rotator cuff tears. All patients completed the pain survey. Mean VAS scores were 25.0 (median 18, SD 22) for anterior, and 25.4 (median 16, SD 25) for posterior injections. The two radiologists achieved different mean VAS scores but closely agreed as to anterior and posterior VAS scores. Conclusion: Arthrography injections were fairly simple to perform under US guidance. Patient discomfort for anterior and posterior injections was equally minor. A tailored approach utilizing anterior or posterior injections, depending on anticipated shoulder pathology, is recommended. Because in posterior injections all artifacts were posterior and readily recognizable, it seems especially suitable for suspected anterior rotator cuff, joint capsule, and labral pathologies.

Multidetector computed tomography of cervical spine fractures in ankylosing spondylitis

Purpose: To analyze multidetector computed tomography (MDCT) cervical spine findings in trauma patients with advanced ankylosing spondylitis (AS). Material and Methods: Using PACS, 2282 cervical spine MDCT examinations requested by emergency room physicians were found during a period of 3 years. Of these patients, 18 (16 M, aged 41-87, mean 57 years) had advanced AS. Primary imaging included radiography in 12 and MRI in 11 patients. Results: MDCT detected one facet joint subluxation and 31 fractures in 17 patients: 14 transverse fractures, 8 spinous process fractures, 2 Jeffersons fractures, 1 type I and 2 type II odontoid process fractures, and 1 each: atlanto-occipital joint fracture and C2 laminar fracture plus isolated transverse process and facet joint fractures. Radiographs detected 48% and MRI 60% of the fractures. MRI detected all transverse and odontoid fractures, demonstrating spinal cord abnormalities in 72%. Conclusion: MDCT is superior to plain radiographs or MRI, showing significantly more injuries and yielding more information on fracture morphology. MRI is valuable, however, in evaluating the spinal cord and soft-tissue injuries. Fractures in advanced AS often show an abnormal orientation and are frequently associated with spinal cord injuries. In these patients, for any suspected cervical spine injuries, MDCT is therefore the imaging modality of choice.

MRI of Acute Meniscal Injury Associated with Tibial Plateau Fractures: Prevalence, Type, and Location

OBJECTIVE The purpose of this study was to evaluate the prevalence, type, and location of meniscal injuries, particularly to assess the prevalence of unstable meniscal tears in acute knee trauma with tibial plateau fractures. MATERIALS AND METHODS A total of 78 menisci were evaluated in 39 patients who had undergone knee MDCT and MRI. Meniscal tears were classified as horizontal, vertical (subdivided into longitudinal and radial), flap, bucket-handle, or complex. The presence of meniscal contusion was documented. The anterior horn, body, and posterior horn were assessed separately for both menisci. Knee arthroscopy was performed on 28 patients. RESULTS Of the 39 patients in the study, 24 had detectable abnormal menisci, for a total of 33 abnormal menisci (42%). Among the 33 meniscal abnormalities were 11 longitudinal tears (33%), 17 contusions (52%), four flap tears (12%), six horizontal tears (18%), and six radial tears (18%). Among the 16 patients with meniscal tears (41% of the 39), 14 patients had an unstable tear. No significant correlation was found between degree of articular depression and site or morphologic features of the meniscal injury. Correspondingly, no statistical correlation was evident between normal menisci and degree of articular depression, nor was a significant correlation found between differing fracture groups and meniscal findings. CONCLUSION A high percentage of patients (36%) with a tibial plateau fracture had an unstable meniscal tear. If a meniscal tear is detected preoperatively, meniscal surgery can be combined with fracture fixation, and reoperation can be avoided. A large number of meniscal contusions were found. Awareness of this abnormality can help radiologists increase specificity by avoiding false-positive findings of meniscal tear.

Wrist injuries; diagnosis with multidetector CT

The aim of the study was to assess acute-phase multidetector CT (MDCT) findings in wrist injuries. We retrieved all emergency room MDCT requests processed in the period from August 2000 to May 2003. All patients with a wrist injury who underwent MDCT initially were included. Imaging studies were evaluated in relation to injury mechanism, fracture location, and fracture type. A total of 6422 MDCT examinations were performed during this 34-month period, and 38 patients (24 male, 14 female, age range 21–73 years, mean age 40 years) met the inclusion criteria. MDCT revealed 56 fractures and 7 dislocations in 29 patients. In 9 patients (24%) MDCT findings were normal. Eleven patients (29%) underwent surgical procedures. The main injury mechanism was a fall (58%). In 33 cases the primary radiograph was available. Compared to primary radiographs, MDCT revealed 9 occult fractures, mainly in small carpal bones. In 14 cases a suspected fracture (of the scaphoid in 7 cases) was ruled out by MDCT. Due to high-quality two-dimensional reformatting, MDCT examinations were not dependent on the wrist’s position in the CT gantry. In the comparison with radiography, MDCT detected occult fractures and ruled out suspected fractures, both mainly in the small carpal bones. High-quality two-dimensional reformats gave significant information about the fracture anatomy. MDCT provides fast and valuable information in assessing complex wrist fractures or when the primary radiograph is equivocal.

Incidence, epidemiology and treatment results of osteosarcoma in Finland - a nationwide population-based study

Abstract Background. Patients diagnosed with osteosarcoma in Finland during 1991–2005 were retrospectively analyzed in a nationwide, population-based study. We focused on the incidence, treatment and outcome of osteosarcoma patients. We also evaluated the value of known prognostic parameters. Material and methods. Osteosarcomas were retrieved from the files of the national Finnish Cancer Registry. Only patients with histologically confirmed osteosarcoma were included in the analysis. Histological review was performed. Results. The study consists of 144 osteosarcoma patients with a mean follow-up of 9.8 years for survivors. Mean annual incidence of histologically confirmed osteosarcoma was 1.8 new osteosarcomas per million. The 10-year sarcoma-specific survival for the whole population was 63% and 73% for patients with local disease at presentation. Overall limb-salvage rate was 73% and local control was 84% for patients with a peripheral tumor. Development of local recurrence and major deviation from the chemotherapy protocol were significant adverse factors for sarcoma-specific survival in multivariate analysis. Conclusion. The present nationwide and population-based study is our second report of treatment and prognosis of osteosarcoma in Finland. With modern chemotherapy the prognosis of local osteosarcoma has improved in Finland from 47% during 1971–1980 and 65% during 1981–1990 at five years to the present 73% during 1991–2005 at 10 years. The 10-year sarcoma-specific survival of 73% is excellent and comparable to results reported with contemporary treatment protocols in high-volume centers. However, improvement in limb-salvage rate and local control probably requires centralization of treatment of this rare disease.

The efficacy of magnetic resonance imaging in acute multi-ligament injuries

This study compares MRI with examination under anaesthesia to surgical findings in evaluating soft tissue injuries in acute multi-ligament knee trauma. Pre-operative MRI was done for 44 patients who underwent surgery for grade III ACL and grade III medial collateral ligament (MCL) injury. In 21 cases both ACL and MCL were treated surgically, but in 23 only ACL. Intra-operative and MRI findings were compared. Accuracy of MRI for medial meniscal tears was 88.6%, sensitivity 80%, and specificity 91.2%; accuracy for lateral meniscal tears was 72.7%, sensitivity 55% and specificity 87.5%. Accuracy and sensitivity for severity of ACL tear was 93.2% and of MCL tear 86.4%. In 88.6% of the knees, bone bruises were visible, with anterolateral femoral and posterolateral tibial bone bruise being the most common. MRI revealed no chondral lesion, but arthroscopy revealed 11. In combined ACL–MCL ruptures, the incidence of concomitant injuries is high and the injuries are best detected with MRI.RésuméCette étude a pour but de comparer les données de l’IRM avec les résultats de l’examen sous anesthésie et les constatations chirurgicales après traumatismes aigus du genou. Une IRM préopératoire a été réalisée chez 44 patients qui ont bénéficié d’un geste chirurgical pour des lésions de grade III du ligament croisé antérieur et de grade III du ligament médio collatéral. Dans 21 cas, le ligament croisé antérieur et le ligament latéral interne ont été réparés chirurgicalement mais dans 23 cas les patients ont bénéficié simplement d’une réparation du ligament croisé antérieur. Les constatations per opératoires et les constations IRM ont été comparées. Pour l’IRM le diagnostic est fait à 88,6% pour les lésions méniscales avec une sensibilité de 80% et une spécificité de 91,2%. En ce qui concerne les lésions du ménisque externe latéral, les constatations IRM sont de 72,7% avec une sensibilité de 55% et une spécificité de 87,5%. Pour les ligaments croisés antérieurs, la sensibilité est de 93,2% et pour le ligament latéral interne de 86,4%. Les érosions osseuses sont visibles et leurs constatations sur le fémur antéro latéral et sur le tibia postéro latéral sont habituelles. L’IRM n’a révélé aucune lésion cartilagineuse mais l’arthroscopie a montré qu’il y en avait 11. Les ruptures combinées du ligament croisé antérieur et du ligament latéral interne sont d’une association fréquente et peuvent être détectées de façon plus facile par l’IRM.

Violence-related facial trauma: analysis of multidetector computed tomography findings of 727 patients

OBJECTIVES The multidetector CT (MDCT) findings of facial trauma in victims of interpersonal violence were assessed. METHODS All MDCT requests for suspected facial injury during a 62 month period were retrieved; 727 cases met the inclusion criteria. Images were interpreted by two researchers by consensus. RESULTS Of the 727 patients (aged 15-86 years old, mean 37), 583 (80.2%) were male and 144 (19.8%) female. Of all the patients, 74% had a fracture, and of these 44% had multiple non-contiguous fractures. CONCLUSIONS Violence is a very common cause of facial injury. Nasal and orbital fractures predominate. Males are more often involved; they are younger, sustain fractures more often and significantly more often present with high-energy fracture patterns. LeFort fractures are often unilateral or asymmetrical, and are frequently accompanied by other, clinically significant fractures. Up to 25% of patients with fractures do not have paranasal sinus effusions.

Muscle changes in brachial plexus birth injury with elbow flexion contracture: an MRI study

BackgroundMuscle pathology of the arm and forearm in brachial plexus birth injury (BPBI) with elbow flexion contracture has not been evaluated with MRI.ObjectiveTo determine whether limited range of motion of the elbow in BPBI is correlated with specific patterns of muscular pathology.Materials and methodsFor 15 BPBI patients, total active motion (TAM) of the elbow (extension–flexion) and the forearm (pronation–supination) were measured. MRI of the elbow joints and musculature allowed assessment of elbow congruency. Fatty infiltration and size reduction of the muscles were graded semiquantitatively.ResultsMean TAM of the elbow was 113° (50°–140°) and that of the forearm 91° (10°–165°). The greater the size reduction of the brachioradialis muscle, the more diminished was elbow TAM. The more extensive the BPBI and muscle pathology of the pronator teres muscle, the more limited was the TAM of the forearm. Pathology of the supinator and brachialis muscles was evident in every patient.ConclusionExtensive BPBI may result in marked limitation of TAM. Elbow flexion contracture seems to be caused mainly by brachialis muscle pathology. Prosupination of the forearm is better preserved when the pronator teres is not severely affected. MRI can reliably show the extent of muscle pathology in BPBI.