Changes in the mechanical properties of femoral cartilage tissue in advanced osteoarthritis.

PURPOSE: The main goal of this article was the analysis of the changes of mechanical properties, thickness and histology of the cartilage in different regions of the femur head in advanced stage of the osteoarthritis. METHODS: The study material consisted of cylindrical specimens (9.7 mm) prepared form proximal epiphysis of the human femur bone after hip arthroplasty. The thickness was determined from the reconstruction of the specimen from microtomography (SkyScan 1172, Bruker®) images. Mechanical properties of the cartilage tissue were identified in static indentation test conducted the use of MTS® Synergie 100 testing machine. Histological study enabled us to determine cartilage total thickness as well as location and orientation of the collagen fibers. RESULTS: Depending on the region of the head, the cartilage tissue thickness was in the range (0.74-2.23 mm). The lowest thickness values were obtained for the R5 region and the lowest for R4. Samples from R1-R4 regions differ by 24%. Measurements of cartilage tissue indentation, determined with the help of Hayes' formula, showed that the values of mechanical parameters in regions R1, R2, R3 and R5 have similar values (the difference between them is about 5.5%). Region R4, which had the smallest thickness, also had the lowest values of mechanical parameters. CONCLUSIONS: Using κ coefficients, proposed by Hayes, enabled us to obtain similar values of mechanical parameters in the regions R1, R2, R3 and R5, despite differences in cartilage tissue thickness. The R4 region, which had the weakest mechanical parameters, was characterized by the strongest reduction of the articular cartilage tissue, which was accompanied by an unformed mass of cartilage residue originating from the abraded surface and bursa fluid.

Micromorphological assessment of bone tissue remodeling in various hip degeneration conditions.

BACKGROUND: The reorganization of bone tissue is closely associated with its metabolism and changes in its internal structure. Metabolism of the bone, which results from the simultaneous processes of resorption and formation of new bone tissue, may depend on the presence and type of arthritis. OBJECTIVES: The objective of the study was to assess, based on the morphological features and mineral composition of bone tissue, changes in the femoral head in various types of hip joint degeneration. MATERIAL AND METHODS: The study group consisted of 21 patients surgically treated for hip joint degeneration. They included 17 women, aged 30-70 years (mean age 52.5 years), and 4 men, aged 38-51 (mean age 48.5 years). The assessment of the morphological condition of the bone and the mineral composition of bone tissue took into account quantitative and qualitative relationships among the mineral components and bone matrix. The structure of spongious bone tissue was analyzed in histological studies, with special attention paid to osteogenesis and osteoclastic processes and the advancement of degeneration. RESULTS: Three main types of degenerative changes in bone tissue of the examined femoral head were recognized: osteoporosis with a prevalence of coarse-fiber bone tissue and decreased osteogenic activity; osteolysis with few osteogenesis centers; and intensified reorganization of bone tissue. In more than half of the examined samples, coarse-fiber bone tissue was replaced by newly formed bone tissue. We observed bone resorption and osteogenesis, which indicate normal homeostasis of the bone tissue. Uneven saturation of spongious bone with mineral components was found. The content of organic and inorganic bone components measured with Ca : P and C : Ca + P ratios had similar values in all types of changes. Only the bone with intense osteolysis contained a smaller quantity of carbon (4.96-8.13%). CONCLUSIONS: Our observations indicate an intense adaptive reorganization of bone tissue depending on external and internal factors, including biomechanical condition.

OSS Implant Fracture as a Complication of Resection Arthroplasty Performed Following High-energy Knee Injury. Case Study.

Treatment of high-energy distal femoral fractures is highly demanding. Advances in osteosynthesis tech-niques now allow for successful treatment, but extensive bone defects associated with the injury can preclude stable bone healing. Modular arthroplasty may be an effective alternative in such cases. Most commonly used during periarticular tumour resection procedures, modular arthroplasty enables functional recovery of the limb. It has been proven to be effective also in traumatic bone defects. The most important limitation of this method is a high level of technical difficulty and possible complications that may require reoperation. The most common complications are infections, periprosthetic fractures and implant wear and loosening. This report presents a case of high-energy injury to the distal femur, with a considerable bone defect treated successfully by modular post resection arthroplasty using a Biomet OSS implant. A spontaneous implant fracture occurred nine years after surgery. This complication had not been previously described in the available literature. A re-vision arthroplasty was performed with similar implants, resulting in functional recovery of the limb and patient satisfaction.

Clinical evaluation of ankle arthrodesis with Ilizarov fixation and internal fixation.

BACKGROUND: Ankle arthrodesis may have internal or external stabilization. We assessed whether the type of stabilization after ankle arthrodesis will affect: (1) functional outcome in Foot and Ankle Ability Measure (FAAM) scale, (2) pain level, (3) period of hospitalization, (4) rate of complications. METHODS: We retrospectively studied 47 individuals after ankle arthrodesis with Ilizarov fixation (group 1, n = 21) and internal stabilization (group 2, n = 26) at our institution in years 2007-2015. Clinical outcomes were measure by: (1) functional outcome in FAAM scale, (2) pain level, (3) period of hospitalization, (4) rate of complications. RESULTS: Total number of complications in Ilizarov group was 13, which corresponded to 0.62 complications per patient on average. In group 2 there were 15 complications, which corresponded to 0.58 complications per patient on average. The intergroup difference in rate of complications was not statistically significant (p = 0.066). In group 1 the mean VAS pain level before treatment was 4.69 and after treatment was 1.5 (p = 0.037). In group with internal stabilization the mean VAS pain level before treatment was 4.71 and after treatment was 2.9 (p = 0.044). In group 1 the mean period of hospitalization was 5.29 days, in group 2 was 5.71 days (p = 0.517). In group 1 the mean functional outcome in FAAM scale was 79.38, in group 2 was 70.11 (p = 0.458). CONCLUSIONS: Ankle arthrodesis with Ilizarov stabilization is associated with lower prevalence of VAS pain level after surgery than after internal screws stabilization. Rate of complications, FAAM functional score and period of hospitalization were not statistically significant between group 1 and 2. Clinical outcome was satisfactory in group 1 and 2, but outcomes in Ilizarov group were slightly better than after internal stabilization.

Sport and physical activity after ankle arthrodesis with Ilizarov fixation and internal fixation.

BACKGROUND: Severe osteoarthritis (OA) of the ankle joint constitutes an important social problem. OBJECTIVES: We used (1) the GRIMBY scale, (2) the LOWER LIMB Activity scale, (3) the UCLA (University of California Los Angeles) activity scale, (4) the VAS (visual analogue scale) ACTIVITY scale, and (5) the FAAM (foot and ankle ability measure) SPORT scale to verify whether the type of ankle joint arthrodesis stabilization affected sports and physical activity levels. MATERIAL AND METHODS: We carried out a prospective clinical study of 47 patients who had undergone ankle arthrodesis with Ilizarov external fixator stabilization (Group 1, n = 21) or internal stabilization with screws (Group 2, n = 26) at Orthopaedic Clinic at the Wroclaw Medical University, Poland, from 2007 to 2015. Sports and physical activity levels were measured by (1) the GRIMBY scale, (2) the LOWER LIMB Activity scale, (3) the UCLA activity scale, (4) the VAS ACTIVITY scale, and (5) the FAAM SPORT scale. RESULTS: A comparison between the average results of Group 1 and Group 2 on the LOWER LIMB Activity scale and the GRIMBY scale before and after surgery revealed no significant differences. In Group 1, the mean scores on the VAS ACTIVITY scale and the UCLA activity scale after treatment were higher than in Group 2. In Group 1, the mean outcome in the SPORT FAAM scale after treatment was 40; in Group 2 it was 30.06. CONCLUSIONS: Ilizarov fixation of ankle arthrodesis is associated with better scores on the FAAM SPORT, UCLA activity and VAS ACTIVITY scales after treatment than internal fixation. The scores on the GRIMBY scale and the UCLA activity scale were significantly higher after treatment than before treatment in both groups. In this study, ankle fusion with Ilizarov fixation and internal fixation was found to be effective in the treatment of ankle arthritis. The levels of sport and physical activity were satisfactory in both groups, but the outcomes after fixation with the Ilizarov apparatus were better than after internal stabilization.

Pedobarographic analysis of body weight distribution on the lower limbs and balance after ankle arthrodesis with Ilizarov fixation and internal fixation.

BACKGROUND: A number of various techniques were proposed to stabilized ankle arthrodesis, among them external and internal fixation. Appropriate balance and adequate distribution of lower limb loads determine normal biomechanics of the locomotor system. We hypothesized that various techniques used to stabilize ankle arthrodesis may exert different effects on (1) balance and (2) distribution of lower limb loads. METHODS: Retrospective analysis included 47 patients who underwent ankle arthrodesis with external stabilization with Ilizarov fixator (group 1, n = 21) or internal stabilization with screws (group 2, n = 26) between 2007 and 2015. Balance and distribution of lower limb loads were determined with a pedobarographic platform. RESULTS: In group 1, average load of the operated and non-operated limb amounted to 48.8% and 51.2%, respectively, and in group subjected to internal stabilization to 48.4% and 51.6%, respectively. Neither the intragroup nor the intergroup differences in the distribution of lower limb loads were statistically significant. Mean length of the center of gravity (COG) path was 137.9 cm for group 1 and 134 cm for group 2, and mean COG area amounted to 7.41 cm2 and 6.16 cm2, respectively. The latter intergroup difference was statistically significant. CONCLUSIONS: Balance after ankle arthrodesis with Ilizarov fixation is worse than after the same procedure with internal stabilization. Despite correction of ankle deformity, musculoskeletal biomechanics still remains impaired. While ankle fusion with either Ilizarov or internal fixation provide appropriate distribution of lower limb loads, none of these procedures normalize patients' balance.

Assessment of the distribution of load on the lower limbs and balance before and after ankle arthrodesis with the Ilizarov method.

Ankle arthrodesis with the Ilizarov method is an accepted form of treatment of advanced degenerative changes of the ankle joint. Incorrect balance and load distribution on the lower limbs may result in pain and dysfunction. The aim of the study was to assess the change of balance and load distribution in lower extremities in patients before and after ankle arthrodesis with the Ilizarov method. Between 2013 and 2016, ankle arthrodesis using the Ilizarov method was performed on 21 patients. The evaluation of balance and percentage of load in each lower limb was performed before the surgery and during the follow-ups. The evaluation was performed using a Zebris pedobarographic platform. Before the surgery, the patients exhibited an average load of 41.9% of body weight in the affected limb, whereas the load in the healthy limb was 58.1%. The difference was statistically significant (p = 0,000031). In two years follow-up, the average load in the treated limbs was 48.19%, whereas the healthy limbs were subjected to an average load of 51.81%. In preoperative tests, the average path length of the center of gravity was 161.55 cm; postoperatively, the average path length of the center of gravity was 129.7 cm (p = 0.00003206). Preoperatively, the average area of the center of gravity was 18.85 cm2; it decreased to 6.19 cm2 (p = 0.000032) postoperatively. Arthrodesis of the ankle with the Ilizarov method improved the statics of the musculoskeletal system by improving the distribution of loads in the lower limbs as well as balance. However, it failed to restore the parameters of a healthy person. Advanced degenerative changes of the ankle disturb the biomechanics of the entire lower limb.

Balance and lower limb loads distribution after Ilizarov corticotomy.

INTRODUCTION: Normal balance and symmetric distribution of lower limb loads are associated with adequate muscle strength, joint mobility and proprioception. The aim of this study was to analyze the distribution of lower limb loads and balance prior to and after axis correction and lengthening with Ilizarov method. MATERIALS AND METHODS: The prospective analysis included 20 patients from our clinic, who have been subjected to distraction-corrective lower limb corticotomies with the Ilizarov method in 2014-2015. Balance and distribution of lower limb loads were determined with a pedobarographic platform. RESULTS: Prior to the surgery, mean loads on affected and non-affected limbs corresponded to42%and58%of body weight, respectively. Mean loads on affected and non-affected limbs during the postoperative examination did not differ significantly. Mean path length of the center of gravity prior to and after the surgery amounted to143.27 cm and 125.11 cm, respectively. Mean area of the center of gravity was 7.81 cm2prior to the surgery and 5.81 cm2after the procedure. DISCUSSION: Our present study showed that distraction-corrective Ilizarov corticotomy may provide more symmetric distribution of lower limb loads and improvement of balance. This outcome should be considered satisfactory from the perspective of the locomotor system statics. Corticotomies with Ilizarov method provide symmetric distribution of loads between non-affected and operated limb.

Increased Radiation but No Benefits in Pedicle Screw Accuracy With Navigation versus a Freehand Technique in Scoliosis Surgery.

BACKGROUND: The clinical value of pedicle screws in spinal deformity surgery is well known; however, screw insertion is demanding and sometimes associated with complications. Navigation systems based on intraoperatively obtained three-dimensional (3-D) images were developed to minimize pedicle screw misplacements. However, there is a lack of data confirming superiority of navigation above other techniques. There are also concerns regarding increased radiation used during the procedure. QUESTIONS/PURPOSES: The purposes of this study were (1) to compare accuracy of the two methods of pedicle screws placement: intraoperative 3-D image navigation versus a freehand technique in patients with idiopathic scoliosis; and (2) to assess the radiation dose received by patients with both methods. METHODS: Between 2014 and 2016, 49 patients underwent posterior spinal fusion with all pedicle screw constructs for idiopathic scoliosis performed by two surgeons. The study design involved alternating the use of the freehand technique and navigation to position pedicle screws in consecutive patients, forming groups of 27 patients with 451 navigated screws and 22 patients with 384 screws positioned freehand. The two groups did not differ in age, sex, or magnitude of deformity. Two observers not involved in the treatment evaluated the position of the screws. The pedicle breach was assessed on intraoperatively obtained 3-D O-arm® scans according to a grading system: Grade 0 = no pedicle wall violation; Grade 1 = perforation ≤ 2 mm; Grade 2 = 2 to 4 mm; and Grade 3 = perforation > 4 mm. Grades 0 and 1 were considered properly positioned and Grades 2 and 3 represented malposition. RESULTS: In terms of accuracy, we found no differences, with the numbers available, between the freehand and navigated groups in terms of the proportion of screws that were properly positioned (96% freehand and 96% in the navigation group, respectively; p = 0.518). Grade 3 pedicle screws were observed only in the freehand group and were all located in the upper thoracic spine. Patients undergoing navigated pedicle screw placement received a greater mean radiation dose than those whose screws were placed freehand (1071 ± 447 mGy-cm versus 391 ± 53 mGy-cm; mean difference, 680 mGy-cm; 95% confidence interval, 217-2053 mGy-cm; p < 0.001). CONCLUSIONS: In patients with moderate idiopathic scoliosis undergoing primary surgery, we did not observe benefits of pedicle screw placement with CT-based navigation, but the patients experienced greater exposure to radiation. LEVEL OF EVIDENCE: Level III, therapeutic study.

The impact of direct vertebral rotation (DVR) on radiographic outcome in surgical correction of idiopathic scoliosis.

INTRODUCTION: Recent developments of spinal instruments allow to address nearly all components of idiopathic scoliosis. Direct vertebral rotation (DVR) maneuver was introduced to correct apical axial vertebral rotation. It is however still not well established how efficiently DVR affects results of scoliosis correction. The object of the study was to evaluate en bloc apical vertebral rotation (DVR) and its impact on coronal and sagittal correction of the spine in patients undergoing surgical scoliosis treatment. MATERIALS AND METHODS: Thirty-six consecutive patients who underwent posterior spinal fusion with pedicle screws only constructs for idiopathic scoliosis. Fifteen patients (20 curves) were corrected by rod derotation only and 21 patients (26 curves) had both rod derotation and DVR. Curve measurements were performed on x-rays obtained before and postoperatively-coronal curves, kyphosis (T2-T12, T5-T12). Spine flexibility was assessed on prone bending x-rays. Apical axial rotation was determined on CT scans obtained intraoperatively and postoperatively. Rotation angle (RAsag) was measured according to Aaro and Dahlborn. RESULTS: We observed reduction of RAsag in all patients; however, in DVR group, decrease was greater, by 31.8% comparing to non-DVR group, by 8.6% (p = 0.0003). Mean coronal correction in DVR group was 68.8% and in rod derotation group without DVR 55% (p = 0.002). No significant correlation was found between degree of derotation obtained and coronal correction. In DVR group T2-T12 kyphosis has increased in 28 (65%) patients whereas in non-DVR group in 31 (69%) cases. Mean value of T2-T12 kyphosis growth was 16.7% in DVR and 22.1% in non-DVR group. These differences however did not occur statistically significant. CONCLUSIONS: Direct vertebral rotation (DVR) maneuver reduces significantly apical rotation of the spine, enhances ability of coronal correction, and it does not reduce thoracic kyphosis.

Radiological evaluation of ankle arthrodesis with Ilizarov fixation compared to internal fixation.

INTRODUCTION: We asked whether the type of ankle joint arthrodesis stabilization will affect: (1) rate of union, (2) rate of adjacted-joint arthritis, (3) malalignment of the ankle joint. MATERIAL AND METHODS: We retrospectively radiological studied 62 patients who underwent ankle arthrodesis with Ilizarov external fixator stabilization (group 1,n=29) or internal stabilization (group 2,n=33) from 2006 to 2015. Radiologic outcomes were mesure by: (1) rate of union, (2) rate of adjacent-joint arthritis, (3) malalignment of the ankle joint. The Levene's test,Mann-Whitney U test and Students t-test were used to the statistical analyses. RESULTS: Ankle fusion was achieved in 100% of patients treated with external fixation and in 88% with internal stabilization. Desired frontal plane alignment was achieved in 100% of patients with external fixation and 76% with internal stabilization. Desired sagittal plane alignment was achieved in 100% of external fixation and 85% of internal stabilization. A total of 14 (48.3%) patients from group 1 showed a radiographic evidence of pre-existing adjacent-joint OA. The radiographic evidence of pre-existing adjacent-joint OA was also found in 27(81.8%) subjects from group 2. Alterations of adjacent joints were also found on postoperative radiograms of 19 (65.5%) patients subjected to Ilizarov fixation and in all 33 patients from group 2. DISCUSION: Ilizarov fixation of ankle arthrodesis is associated with lower prevalence of adjacent-joint OA and ankle joint misalignment,and with higher fusion rates than after internal fixation.Although achieving a complex ankle fusion is generally challenging,radiological outcomes after fixation with the Ilizarov apparatus are better than after internal stabilization.

Effect of elliptical deformation of the acetabulum on the stress distribution in the components of hip resurfacing surgery.

Hip resurfacing surgery is a matter of controversy. Some authors present very good late results of 99% survival outcomes. However, national records of implants point to the series of complications connected with biomechanical flaws of the implant. These results implicate the experimental research on biomechanical properties of HRS. The aim of the research was to define the nature of cooperation between the components of hip resurfacing surgery (HRS) and the influence of the deformation of acetabulum, the size of the implant and the nature of the bone surface on the stress distribution in the acetabulum and the femoral component. The calculations were run with the use of the finite element method (FEM), using the ANSYS bundle for this purpose. Four decrete models of the studied system were made: a model with the elements of the system connected with glue, a perfect spherical model with cooperating surfaces, a model reflecting an elliptical deformation of the acetabulum, and a model with different sizes of the implant. The results indicate that the stress values obtained for models with the ideally spherical acetabulum cannot cause significant deformation of cooperating implants. In the case of loads of the elliptically deformed acetabulum significant point stress concentrations can be observed in the spots of joint. The size of the acetabular and femoral components of HRS has influence on the stress concentration on the internal surface of the acetabulum as well as in the bone tissue surrounding the madrel of the femoral component. Moreover, physical properties of the base surface surrounding the HRS components have influence on the size of stress in the acetabulum and the femoral component.

Methods of reducing allogeneic blood demand in orthopedic surgery.

Despite advances in this field, allogeneic blood transfusion still carries a lot of risk; the availability of heterologous blood is also constantly decreasing. We describe the most popular methods for reducing the allogeneic blood requirement. Basic information is presented about the physiological mechanisms of compensation for intraoperative blood loss, which can be compromised by respiratory and cardiovascular disease or infections. Preoperative anemia (manifested by low hemoglobin levels) is statistically the most significant factor that increases the need for allogeneic blood transfusion. This paper evaluates the importance of oral and intravenous iron supplementation in the perioperative period, and the use of erythropoietin to boost Hb levels. Minimizing intraoperative blood loss also decreases the need for transfusion, and may be accomplished via meticulous hemostasis, an appropriate surgical approach, atraumatic surgical technique, reduced surgery time, and rational tourniquet use. Controlled intraoperative hypotension is a method of proven efficacy. Synthetic antifibrinolytic agents are also used to reduce perioperative blood loss; however, few clinical trials have focused on the use of such drugs in orthopedics. The use of postoperative drainage is still debatable. The allogeneic blood requirement can also be reduced by autologous blood transfusion. Autologous transfusion can be accomplished by preoperative autotransfusion, preoperative hemodilution, and intra- or postoperative blood salvage. It is currently the safest method of compensating for perioperative blood loss, avoiding all the described risks of heterologous blood transfusion.

Influence of cementless cup surface on stability and bone fixation 2 years after total hip arthroplasty.

Loss of fixation between bone and implant surface is one of the main treatment problems in total hip arthroplasty. It might lead to implant instability, bone loss and treatment failure resulting in revision surgery. Surface modification is a method for improving bone response to implant and increasing implant osseointegration. However, the currently applied modifications such as hydroxyapatite coatings do not meet expectation and do not provide good clinical result. The object of the study was to evaluate the influence of acetabular cup surface modification on fixation and bone remodelling in total hip arthroplasty. Clinical and radiological outcomes were evaluated in patients two years after cementless total hip replacement. Two groups were compared: patients with acetabular component with uncoated titanium surface and patients with hydroxyapatite-coated acetabular surface. Hips X-rays were analysed for early signs of losing stability of acetabular cups. Two years after surgery the analysis of X-rays did not reveal any statistical differences in stability, migration of acetabular components of endoprosthesis between both groups. No differences were also observed in bone remodelling around implants. Particularly high percentage of cups, i.e. 17.64%, were classified into the group with high risk of early implant loosening, i.e., the group with HA coatings. Hydroxyapatite coatings on titanium cementless acetabular cups implanted by press-fit technique have no influence on their stability, bone-implant fixation and the remodelling of bone surrounding an implant two years after surgery.

Evaluation of blood loss and significance of postoperative autotransfusion in knee joint alloplasty.

BACKGROUND: The aim of this paper is to evalute perioperative blood loss associated with total cemented knee joint alloplasty, with special regard to specific factors that may influence this loss. Additionally, the significance of postoperative autotransfusion in these procedures is assessed. MATERIALS AND METHODS: The study group consisted of 85 patients (61 females and 24 males); in 32 cases a postoperative autotransfusion system was used (CBCII ConstaVac, Stryker). Factors analysed comprised pre- and postoperative hemoglobin levels, drain blood loss, heterologous blood transfusion volume and reasons for the transfusion, including co-morbidities. RESULTS: Allogeneic blood transfusion was necessary in 54.72% of the patients who did not have autotransfusion and in 34.38% of the patients who received autotransfusion. The mean volume of blood collected in the drains was 882 ml, while the mean volume of reinfused blood amounted to 524.2 ml. Hypertensive patients experienced greater postoperative blood loss. The average drop in hemoglobin levels was 3.6 g/dl and was smaller by 0.6 g/dl in patients who received autotransfusion. The lowest preoperative hemoglobin values occurred in patients who required heterologous blood transfusion despite autotransfusion. Heterologous blood transfusion was performed at a hemoglobin level of 8.4 g/dl; in patients with a concomitant ischemic heart disease the cut-off value was 9.6 g/dl. CONCLUSIONS: 1. The average drop in hemoglobin levels associated with knee alloplasty was 3.5 g/dl. The volume of recovered blood used for post-operative autotransfusion was approx. 500 ml. 2. A low preoperative hemoglobin level is the most significant risk factor for heterologous blood transfusion. 3. Co-mordibities need to be taken into consideration when determining the amount of blood required.

Kyphosis correction after vertebroplasty in osteoporotic vertebral compression fractures.

Percutaneous vertebroplasty is a minimally invasive method of treating vertebral compression fractures aimed mainly at reduction of pain. It has been observed that fractured vertebral bodies filled in with cement might also influence the increase of their height and thus lead to reduction of post-traumatic spine kyphosis. The aim of the research was to assess the possibility of reducing the kyphotic deformation of operated spine through kyphosis measurement of vertebras adjacent to fracture. 24 patients underwent percutaneous vertebroplasty on account of compression fracture of 40 vertebral bodies in thoracic and lumbar regions. On digital x-ray spine images taken in patients before and after surgery the angle of kyphosis or lordosis of bodies above and below the fractured vertebra was measured with the use of the Cobb method. Vertebroplasty in the material examined caused reduction of kyphosis in 33 cases (80.48%) and correction by 5.78° on average. No regularity was found either between the occurrence of correction (and its level) and operated spine region or between the possibility of kyphosis correction and time that passed between fracture and surgery.

Evaluation of dynamic formation of cervical spine column based on functional radiological studies in patients after cervical spine injury.

The purpose of this study was to evaluate cervical spine function, based on our own functional method of roentgenometric analysis in patients who suffered from cervical spine sprain injury. Study involved 72 patients who suffered from cervical spine whiplash injury. Conventional plain radiographs in all patients included three lateral views: maximum flexion, neutral (resting) and maximum extension. All views allowed roentgenometric evaluation of ligament instability of the lower cervical spine C5-C7 according to the White and Panjabi criteria. Furthermore, based on literature analysis and their own clinical observations, the authors proposed new classification of dynamic formation of cervical spine column. The dynamic formation of cervical column is evaluated based on pathomechanical chain of being between normal and unstable. Authors' own evaluation system in flexion views can be useful in diagnosis and treatment of this type of injury.

Influence of whiplash injury on cervical spine stability.

The aim of this study was to define the influence of whiplash injury on cervical spine stability. The study involved 72 patients who had suffered from sprain injury to cervical spine of 0°-III° according to QTF. To verify the results the authors examined the control group whose representatives have never suffered from any cervical spine injury and met all the exclusion criteria. Conventional plain radiographs in both groups showed three lateral views: maximum flexion, neutral (resting) position and maximum extension view. The results of image studies were subjected to roentgenometric analysis to find mechanical symptoms of instability according to radiological criteria: AADI, anterior translation and regional angulation. The authors demonstrated that there was no influence of whiplash injury on mechanical stability of cervical spine measured on radiograms in static-functional lateral views.

Epidemiology of distal radius fractures in own material--own experience.

BACKGROUND: Although distal radius fractures constitute 1/6 of all fractures in humans, epidemiology of the fracture has been a subject of limited number of publications in Polish medical literature. MATERIALS AND METHODS: Epidemiological data of 395 patients (277 females, 118 males) diagnosed with distal radius fracture and treated between January 2003 and May 2005 were collected. 81 patients were seen at 12-month and over follow-up and then categorized according to the AO classification system. They were also examined for subsequent osteoporotic fractures. BMD values were analysed in patients who had undergone bone density scans. RESULTS: Distal radius fractures constituted 18% of all fractures (77% of forearm fractures) treated during the study period. The mean age of patients was 58 years (females 63.5, males 44.8). Respective age groups presented significant gender-related differences in morbidity. The morbidity in women increased rapidly in the 6th decade of life, whereas was fairly stable in men. An analysis of fracture mechanism also pointed to osteoporotic changes as a pathogenic factor. CONCLUSION: Distal radius fractures are the most common fractures in humans. This type of fracture especially in women and older age groups is due to osteoporotic changes and constitutes a risk factor of subsequent osteoporotic fractures. Despite many morphological forms, distal radius fractures in almost 2/3 cases can be allocated into 4 main subgroups.

Elliptical head hemiarthroplasty in the treatment of femoral neck and head fractures--preliminary report.

BACKGROUND: The aim of his study is to evaluate efficacy of elliptical head hemiarthroplasty in treatment of femoral neck and head fractures and related complications in young patients under 55 years of age. MATERIAL AND METHODS: Uncemented elliptical head hemiarthroplasty was performed in 14 patients aged 28-55, mean age of 46,7 years, out of whom 12 diagnosed with a femoral neck fracture or related complications and 2 with a femoral head fracture. Mean follow-up period was 4,5 years, range from 10 months to 6 years. The Harris Hip Score was applied for evaluation of functional results. The radiographic analysis was based on standard anteroposterior and axial radiographic projections. Acetabular cartilage erosion was assessed according to the Wetherell et al radiographic method of measurement. RESULTS: The functional results ranged from 58 to 97 points, mean 85,28 points (according to the HHS). The radiographs revealed no signs of stem loosening. No cartilage erosion or migration of the prosthesis were observed in the study. CONCLUSION: An elliptical shape of the prosthetic head reflects the anatomy of the hip reducing the risk of acetabular cartilage erosion and migration of the prosthesis. We conclude that modular elliptical head hemiarthroplasty can be a useful method of management of femoral neck or head fractures and related complications in younger patients.