Anatomical considerations of C2 lamina for the placement of translaminar screw: a review of the literature.

PURPOSE: The thorough knowledge of C2 lamina anatomy is essential for the avoidance of complications during screw fixation. We performed a review of the literature, aiming to detect what was found about anatomical feasibility of C2 translaminar fixation in different populations, along with possible recommendations for the avoidance of complications, and to detect whether factors such as race or gender could influence axis lamina anatomy and fixation feasibility. METHODS: We performed a search in PubMed and Cochrane database of systematic reviews for studies which correlated axis lamina anatomy with fixation feasibility. We extracted data concerning measurements on C2 lamina, the methods and conclusions of the studies. RESULTS: Twenty-six studies met our inclusion criteria. The studies mainly focused on Asian populations. Male gender was generally related to larger anatomical parameters of C2 lamina. The use of a C2 translaminar screw with a diameter of 3.5 mm was generally feasible, even in children, but there was disagreement about risk of vertebral artery injury. Computed tomography was most frequently recommended preoperatively. Three-dimensional reconstruction was suggested by some authors. CONCLUSION: C2 lamina anatomy generally permitted screw fixation in most studies, but there was disagreement about risk of vertebral artery injury. Preoperative computed tomography was generally recommended, while, according to some authors, three-dimensional reconstruction could be essential. However, there is a relative lack of studies about non-Asian populations. More research could further illustrate the anatomy of C2 lamina, clarify the safety of axis fixation for more populations and perhaps modify preoperative imaging protocols.

Morphometric analysis of the odontoid process: using computed tomography--in the Greek population.

AIM: A morphometric analysis of the odontoid process of the A2 vertebra, in the Greek population, was conducted using CT scan. We aimed to determine the feasibility to use one or two screws when treating fractures of this anatomic element. PATIENTS AND METHODS: One hundred and fifteen patients (57 men) of a mean age of 48 years (16-95 years) underwent a cervical spine CT scan examination. The anterior-posterior and transverse diameters of the odontoid process were measured from the base, at 1-mm interval upward on axial CT images. The length from the tip of the odontoid process to the anterior-inferior angle of the body of the axis was calculated. Data concerning the height and weight of the examined patients were collected. RESULTS: The mean transverse and anterior-posterior distances were found to be 11.46 and 10.45 mm, respectively, for the upper end of the odontoid process. At the neck level of the odontoid process, the equivalent mean values were 11.12 and 8.73 mm, respectively, while at the base, these distances were found to be 13.84 and 12.3 mm, respectively. The mean distance from the tip of the odontoid to its base was 17.25 and 17.28 mm, respectively, while the mean distance from the tip of the dens to the anterior-inferior corner of the axis' body was 39.2 mm. Men showed greater values than women. CONCLUSIONS: In this study, it was shown that in the Greek population there is enough room for one 4.5-mm or one 3.5-mm cannulated screw to be used. The application of two 3.5-mm screws is feasible in 58.6 % of the male and 26.3 % of the female population. This confirms that the knowledge of the true dimensions of the odontoid process is of paramount importance before the proper management of fractured dens using the anterior screw technique.

Expression of macrophage elastase (MMP12) in rat tail intervertebral disc and growth plate after asymmetric loading.

OBJECTIVES: The aim of this study was to examine whether asymmetric loading influences macrophage elastase (MMP12) expression in different parts of a rat tail intervertebral disc and growth plate and if MMP12 expression is correlated with the severity of the deformity. METHODS: A wedge deformity between the ninth and tenth tail vertebrae was produced with an Ilizarov-type mini external fixator in 45 female Wistar rats, matched for their age and weight. Three groups were created according to the degree of deformity (10°, 30° and 50°). A total of 30 discs and vertebrae were evaluated immunohistochemically for immunolocalisation of MMP12 expression, and 15 discs were analysed by western blot and zymography in order to detect pro- and active MMP12. RESULTS: No MMP12 expression was detected in the nucleus pulposus. Expression of MMP12 in the annulus progressively increased from group I to groups II and III, mainly at the concave side. Many growth plate chondrocytes expressed MMP12 in the control group, less in group I and rare in groups II and III. Changes in cell phenotype and reduction of cell number were observed, together with disorganisation of matrix microstructure similar to disc degeneration. ProMMP12 was detected at the area of 54 kDa and active MMP12 at 22 kDa. CONCLUSIONS: Expression of MMP12 after application of asymmetric loading in a rat tail increased in the intervertebral disc but decreased in the growth plate and correlated with the degree of the deformity and the side of the wedged disc. Cite this article: Bone Joint Res 2014;3:273-9.

Comparative study of internal and hybrid external fixation in tibial condylar fractures.

BACKGROUND: The spectrum of injuries to the tibial plateau is so great that no single method of treatment has been proven to be uniformly successful. The purposes of this study were to evaluate the clinical results, to identify the advantages and disadvantages and to take out useful conclusions of the application of the internal and hybrid external fixation in the treatment of these fractures. METHOD: Sixty tibial condylar fractures, of all types, according to Schatzker's classification were treated with open reduction and internal fixation (30 patients) or with hybrid external fixation (30 patients). The following parameters were recorded: time of surgical procedure, time of postoperative hospitalization, time of starting of weight bearing on the affected extremity, complications, and postoperative functional (according to Knee Society Score) and radiological results (according to Rasmussen's Radiological Score). The average time of follow-up was 12 months. RESULTS: Neither of the two methods showed superiority regarding the duration of the surgical procedure [mean difference 4.4 ± 5.4 (min), P = NS], the postoperative hospitalization time [0.6 ± 0.7 (days), P = NS], and the radiological and functional evaluation (χ(2), P = NS for all comparisons). However, the internal fixation method proved to be superior to the hybrid external fixation regarding the time of starting the weight bearing [3.1 ± 0.4 (weeks), P < 0.001]. CONCLUSION: Internal fixation showed superiority to the time starting of weight bearing as it occurred at an earlier time than that of hybrid external by almost 3 weeks whereas no other differences were identified in the other parameters regarding patients' rehabilitation.

The anatomy of the ACL and its importance in ACL reconstruction.

The anterior cruciate ligament (ACL) anatomy is very significant if a reconstruction is attempted after its rupture. An anatomic study should have to address, its biomechanical properties, its kinematics, its position and anatomic correlation and its functional properties. In this review, an attempt is made to summarize the most recent and authoritative tendencies as far as the anatomy of the ACL, and its surgical application in its reconstruction are concerned. Also, it is significant to take into account the anatomy as far as the rehabilitation protocol is concerned. Separate placement in the femoral side is known to give better results from transtibial approach. The medial tibial eminence and the intermeniscal ligament may be used as landmarks to guide the correct tunnel placement in anatomic ACL reconstruction. The anatomic centrum of the ACL femoral footprint is 43 % of the proximal-to-distal length of lateral, femoral intercondylar notch wall and femoral socket radius plus 2.5 mm anterior to the posterior articular margin. Some important factors affecting the surgical outcome of ACL reconstruction include graft selection, tunnel placement, initial graft tension, graft fixation, graft tunnel motion and healing. The rehabilitation protocol should come in phases in order to increase range of motion, muscle strength and leg balance, it should protect the graft and weightbearing should come in stages. The cornerstones of such a protocol remain bracing, controlling edema, pain and range of motion. This should be useful and valuable information in achieving full range of motion and stability of the knee postoperatively. In the end, all these advancements will contribute to better patient outcome. Recommendations point toward further experimental work with in vivo and in vitro studies, in order to assist in the development of new surgical procedures that could possibly replicate more closely the natural ACL anatomy and prevent future knee pathology.

Pancreatic cancer's initial presentation: back pain due to osteoblastic bone metastasis.

Pancreatic cancer may cause osteolytic metastases, but the osteoblastic ones are extremely rare. In addition, it almost always presents with symptoms related to the invasion of the structures in the abdomen. Symptoms from bone metastases are rare and, if seen, are in the late phase of the course. We present a case of cancer of the body of the pancreas, which presented with severe back pain due to an osteoblastic lesion to L3 vertebra. Biopsy of the vertebra led to the diagnosis. Radiographs, computed tomography, magnetic resonance and scintigraphic images as well as pathology slices are shown. The present case raises the issue that pancreatic cancer, as a cause of an osteolytic bone lesion, should not be overlooked in an unknown primary investigation.

Anatomical study and colour Doppler assessment of the skin perforators of the anterior tibial artery and possible clinical applications.

BACKGROUND: Traumatic or trophic defects of the soft tissue of the lower leg are quite often very difficult to manage, especially in the distal third of the leg. Fasciocutaneous flaps are a relatively simple option for covering small- and medium-sized defects of the lower leg. The aim of this study is to investigate the distribution of septocutaneous perforators of the anterior tibial artery and their possible clinical applications. METHODS: An anatomical study was performed on 50 fresh adult cadaveric lower extremities. Using coloured contrast materials, the location of septocutaneous perforators, originating from the anterior tibial artery, were mapped. These findings were then compared with colour Doppler imaging (CDI) data in 20 living volunteers. RESULTS: The septocutaneous perforators of the anterior tibial artery follow a reproducible pattern all over the lower leg (septa I, II and III). In the distal segment, we found relatively few perforators. There was a marginal difference between cadaveric and CDI data for perforators with diameter >or=1mm. The average number of anterior tibial artery septocutaneous perforators in anatomical dissections was 6.6+/-2.4, while CDI revealed 8.2+/-3.2 perforators in living volunteers (P=0.053). In five areas of the lower leg, there is a >50% chance that a septocutaneous perforator with diameter >or=1mm is coming off the anterior tibial artery. Anatomical dissections for a cutaneous territory 5 cm above the lateral maleollus, and 10 cm in width, revealed 6.1+/-2.2 septocutaneous perforators (range 4 to 12). CONCLUSIONS: CDI, paired with knowledge of anatomical details, is a reliable tool for preoperative identification of septocutaneous perforators of 1mm or larger outer diameter, thus providing critical information for planning and harvesting safe fasciocutaneous flaps of the lower leg. Additionally, according to our anatomical study, a new transverse fasciocutaneous flap (Type B according to the Nahai-Mathes classification), located over the distal anterolateral third of the lower leg and based on perforators of the anterior tibial artery, may be successfully used for covering selected defects of the distal third of the lower leg.

Multifocal spinal and extra-spinal Mycobacterium chelonae osteomyelitis in a renal transplant recipient.

Only localized cases of Mycobacterium chelonae osteomyelitis have been reported. In this article, a 55-year-old immunosuppressed man with M. chelonae osteomyelitis and multiple spinal and extra-spinal involvement is presented. The patient had nodule-pustular skin lesions, spondylodiscitis at multiple levels, and osteolytic lesions at extra-spinal locations. Biopsy and cultures of the osseous lesions showed M. chelonae osteomyelitis. The patient started antimycobacterial chemotherapy with ciprofloxacin and clarithromycin. Progressive cervical kyphosis associated with anterior wedged deformity of the C5 vertebra and posterior C5-C6 spondylolisthesis resulted in compression of the spinal cord and neurological impairment. The patient underwent anterior decompression and C4-C6 arthrodesis using a titanium mesh cage and cervical plate. About 15 months after the initiation of chemotherapy and 5 months after surgery, the patient was pain free, with significant improvement of his neurological function. In the presence of immunosuppression, the physician should be alert for unusual or opportunistic pathogens of osteomyelitis. Long-term antimicrobial chemotherapy and surgical intervention is the cornerstone of successful treatment of multifocal bone M. chelonae infection.

Intraoperative Bier's block as supplement to insufficient axillary block anesthesia in upper extremity surgery.

The authors reviewed 52 patients who underwent Bier's block, as supplementary anesthesia for insufficient axillary block in upper extremity surgical procedures. Prior to proceeding to the Bier's block, the mean value of pain using the visual optical analogue scale (VAS) was 7.0. In 48 of the patients supplementation with the Bier's block was sufficient (mean VAS score of 1.0) and all patients were comfortable throughout the procedure. In the remaining four patients supplementation with narcotics and sedatives via the other i.v. line was required. Intraoperative Bier's block provides a safe and effective alternative way of successfully compensating for an insufficient axillary block in upper extremity surgical procedures.

The symmetry of the medial collateral and anterior cruciate ligament properties: a biochemical study in the rat hind limb.

The medial collateral (MCL) and the anterior cruciate ligament (ACL) of the rat's knee are frequently used in biomedical research and occasionally in ligament healing studies. The contralateral normal ligament serves as a control. In this study the presence of symmetry in the biomechanical properties of the MCL and the ACL was investigated. Bilateral femur-MCL-tibia and femur-ACL-tibia preparations were obtained from the hind limbs of sixty rats and were subjected to tensile testing to failure under the same loading conditions. Tensile load to failure, stiffness and energy absorption capacity were measured and the mode of failure was recorded. All biomechanical parameters were not significantly different between the two knees of the same animal, although significant individual variation was evident. The most common mechanism of failure was mid-substance tear. Symmetry seems to exist in the biomechanical properties of the MCL and the ACL in the rat knee. When ligament healing is evaluated, increased group size is necessary and the use of a normal control group may be advisable. The contralateral normal knee ligament may serve as a control when the properties of an injured ligament are evaluated and when the parameters of tensile testing failure under similar load conditions are applied.

Degenerative spondyloarthropathy of the cervical and lumbar spine in jockeys.

This prospective study analyzed the long-term effects of horse riding on the cervical and lumbar spine of jockeys. Thirty-two jockeys were observed for 13 years. All jockeys had clinical and radiographic evaluation of the spine; three consecutive age groups were studied. Results were compared to age-matched, normal population control groups. The incidence of degenerative changes of the spine was higher in the jockeys compared with the control groups and was more prominent in the older age group for both the lumbar and cervical spine. These findings suggest that equestrian sports, particularly professional horse riding, apart from the increased risk of direct spinal injury caused by a fall from the horse, can lead to progressive spine degeneration as a result of repetitive trauma and increased physical stress on the spine.

Treatment of lumbosacral radicular pain with epidural steroid injections.

Fifty patients with an average age of 47 years received epidural steroid injections for lumbosacral radicular pain due to disk herniation or spinal stenosis. All patients had failed previous conservative treatment. Mean follow-up was 24 months (range: 12-36 months). Immediately after injection, all 50 patients reported various degrees of relief from leg and back pain. At the last follow-up examination, 68% of patients were asymptomatic, 20% had no change in preinjection radicular symptoms, and 12% had various degrees of relief. No significant correlation was found between pain relief, age, or number of injections. Early pain relief may be anticipated after epidural steroid injections in 80% of patients with radicular symptoms due to disk herniation or spinal stenosis.

Long-term mechanical stability of the impacted morselized graft-cement interface in total joint replacement: an experimental study in dogs.

This experimental study compared the long-term (12 months) mechanical stability of the morselized graft-cement interface with the conventional bone-cement interface in both femoral bones of 10 adult dogs. For mechanical testing, three-point bending and push-out loading tests of composite bone-cement beams were used, while the incorporation of the graft was assessed by serial radiographs. Although the parameters fracture load and interface failure load showed inferior values in the specimens with a morselized graft-cement interface compared to those in specimens with a conventional bone-cement interface, no statistically significant differences were found between groups. Radiographic reconstitution of the lateral femoral cortex was observed in all animals at 3 months while signs of advanced remodeling were apparent at 6 months. These results indicate the long-term mechanical stability of the impacted morselized graft-cement interface is comparable to that of the conventional bone-cement interface created in primary total hip replacements provided the grafted area is protected from early heavy loading.

Operative treatment for Maisonneuve fracture of the proximal fibula.

This study reviewed operative treatment of Maisonneuve fracture of the fibula in 26 patients. Operative treatment consisted of restoration of the fibular length, repair of the lateral and medial ankle ligamentous structures, and placement of one or two suprasyndesmotic screws. After average follow-up of 6.4 years, the clinical results were satisfactory in 23 (88.4%) patients. Operative treatment is the treatment of choice for Maisonneuve fractures, and a satisfactory outcome may be anticipated after appropriate management of any associated bony and syndesmotic injuries.

Pain pattern in multiple vertebral hemangiomas involving non-adjacent levels: report of two cases.

Hemangioma of the bone is a benign tumor usually involving the spine and the bones of the skull and pelvis. It may be either a single lesion or part of a generalized multifocal disease. Multiple lesions involving non-adjacent vertebrae are rare. Two cases of multiple vertebral hemangiomas at non-adjacent levels with different pain patterns are presented at various stages of follow-up in order to emphasize the fact that multiple vertebral hemangiomas may present with different clinical characteristics over a long period of time. The change in the location and pattern of the initially presented pain in both patients suggested the possibility of multiple level involvement. Investigation revealed multiple hemangiomas involving three non-adjacent vertebrae in the first patient and four in the second. We stress the fact that the existence of multiple non-adjacent lesions may remain undiagnosed for a considerable period of time and may be responsible for even longer-term recurrent episodes of pain. Multifocal location of back pain in patients with a known vertebral hemangioma may be considered a relative indication for the presence of multiple non-adjacent level lesions.

Spontaneous interbody fusion after controlled injuries to the spine: an experimental study in rabbits.

To evaluate the rationale of spontaneous spine fusion after a spinal injury, the authors conducted an experimental study that consisted of three types of controlled injuries to a rabbit spine model. The first was injury to the intervertebral disk (type I injury). The second was injury of the intervertebral disk along with injury to one of the adjacent vertebral end plates (type II). In type III injury, both the opposing end plates were injured along with the intervertebral disk. In 38 rabbits, a total of 82 injuries of these three types were inflicted. Twenty-six injuries were of type I (n = 22 rabbits), 26 were type II (n = 24 rabbits), and 30 were type III (n = 26 rabbits). Spontaneous fusion occurred only in type III injuries. From the 30 type III injuries, fusion occurred in 20 (66.6%). For an autofusion to occur, both epiphyseal plates may be injured. In the clinical situation, this observation suggests that a radiographically obscure lesion of both neighboring vertebrae may proceed to autofusion of that spinal segment observed later.

Seven- to 20-year outcome of lumbar discectomy.

STUDY DESIGN: A retrospective, follow-up study. OBJECTIVES: To assess the effects of conventional surgery for lumbar disc herniation over an extended period of time and to examine factors that might correlate with unsatisfactory results. SUMMARY OF BACKGROUND DATA: Although the short-term results of lumbar discectomy are excellent when there is a proper patient selection, the reported success rates in the long-term follow-up studies vary, and few factors have been implicated for an unsatisfactory outcome. METHODS: One hundred-nine patients with surgically documented herniated lumbar disc were analyzed, retrospectively, by an independent observer. Long-term follow-up (mean 12.2 years) was done by a mailed, self-report questionnaire that included items about pain relief in the back and leg, satisfaction with the results, need for analgesics, level of activity, working capacity, and reoperations. Subjective disability was measured by the Oswestry questionnaire. Radiographic review was carried out in 66% of patients. End results were assessed using the modified Stauffer-Coventry's evaluating criteria. Several variables were examined to assess their influence to the outcome. RESULTS: The late results were satisfactory in 64% of patients. The mean Oswestry disability score was 18.9. Of the 101 patients who had primary procedures, 28% still complained of significant back or leg pain. Sixty-five percent of patients were very satisfied with their results, 29% satisfied, and 6% dissatisfied. The reoperation rate was 7.3% (8 patients), about one-third of which was due to recurrent disc herniation. Sociodemographic factors predisposing to unsatisfactory outcome, including female gender, low vocational education, and jobs requiring significant physical strenuousness. Disc space narrowing was common at the level of discectomy, but was without prognostic significance. CONCLUSIONS: The long-term results of standard lumbar discectomy are not very satisfying. More than one-third of the patients had unsatisfactory results and more than one quarter complained of significant residual pain. Heavy manual work, particularly agricultural work, and low educational level were negative predictors of a good outcome. These indicators should be used preoperatively to identify patients who are at high risk for an unfavorable long-term result.