Value of Proximal Femur Geometry in Predicting Occult Hip Fracture

Background and Objectives: Patients with occult hip fractures are a difficult subgroup to treat. MRI is the gold standard for diagnosing occult proximal femur fractures but is costly and may not be readily available in an emergency setting. The purpose of this study was to determine whether changes in the proximal femur geometry can predict the likelihood of an occult hip fracture in patients presenting with hip pain following a ground-level fall. Material and Methods: Patients admitted to the hospital with a clinical suspicion of a hip fracture but initial negative radiographs over a seven-year period were included. All patients were additionally investigated with an MRI scan, and retrospectively, six radiologic parameters were obtained on plain radiographs: The cortical thickness index (CTI), the canal to calcar ratio (CCR), the canal flare index (CFI), the morphological cortical index (MCI), the canal bone ratio (CBR) and the canal bone aria ratio (CBAR). Subsequently the result of the plain radiographic indices of the patients with a negative MRI (Group A, no occult fracture) were compared to those with a positive MRI (Group B, occult fracture). Results: A total of 78 patients (59 female, 19 male) could be included in the study. The mean age was 82 years. The univariate analyses revealed a poor predictive ability of all radiological parameters with AUC values ranging from 0.515 (CBR) to 0.626 (CTI), whereas a multivariate prognostic model demonstrated improved prognosis (AUC = 0.761) for the CTI (p = 0.024), CBAR (p = 0.074) and CRR (p = 0.081) as the most promising predictive radiological parameters. Conclusions: Single radiologic indices obtained from conventional X-rays of the proximal femur have a weak predictive value in detecting occult fractures of the hip and cannot be used as clinical decision-making factors.

The Geriatrics at Risk Score (GeRi-Score) for mortality prediction in geriatric patients with proximal femur fracture - a development and validation study from the Registry for Geriatric Trauma (ATR-DGU)

This study developed an easy-to-use mortality prediction tool, which showed an acceptable discrimination and no significant lack of fit. The GeRi-Score was able to predict mortality and could distinguish between mild, moderate and high risk groups. Therefore, the GeRi-Score might have the potential to distribute the intensity of medical care.

PURPOSE

Several mortality-predicting tools for hip fracture patients are available, but all consist of a high number of variables, require a time-consuming evaluation and/or are difficult to calculate. The aim of this study was to develop and validate an easy-to-use score, which depends mostly on routine data.

METHODS

Patients from the Registry for Geriatric Trauma were divided into a development and a validation group. Logistic regression models were used to build a model for in-house mortality and to obtain a score. Candidate models were compared using Akaike information criteria (AIC) and likelihood ratio tests. The quality of the model was tested using the area under the curve (AUC) and the Hosmer-Lemeshow test.

RESULTS

38,570 patients were included, almost equal distributed to the development and to the validation dataset. The AUC was 0.727 (95% CI 0.711 - 0.742) for the final model, AIC resulted in a significant reduction in deviance compared to the basic model, and the Hosmer-Lemeshow test showed no significant lack of fit (p = 0.07). The GeRi-Score predicted an in-house mortality of 5.3% vs. 5.3% observed mortality in the development dataset and 5.4% vs. 5.7% in the validation dataset. The GeRi-Score was able to distinguish between mild, moderate and high risk groups.

CONCLUSIONS

The GeRi-Score is an easy-to-use mortality-predicting tool with an acceptable discrimination and no significant lack of fit. The GeRi-Score might have the potential to distribute the intensity of perioperative medical care in hip fracture surgery and can be used in quality management programs as benchmark tool.

The Influence of a Modified 3rd Generation Cementation Technique and Vaccum Mixing of Bone Cement on the Bone Cement Implantation Syndrome (BCIS) in Geriatric Patients with Cemented Hemiarthroplasty for Femoral Neck Fractures

Background and Objectives: Cemented hemi arthroplasty is a common and effective procedure performed to treat femoral neck fractures in elderly patients. The bone cement implantation syndrome (BCIS) is a severe and potentially fatal complication which can be associated with the implantation of a hip prosthesis. The aim of this study was to investigate the influence of a modified cementing technique on the incidence of BCIS. Material and Methods: The clinical data of patients which were treated with a cemented hip arthroplasty after the introduction of the modified 3rd generation cementing technique were compared with a matched group of patients who were treated with a 2nd generation cementing technique. The anesthesia charts for all patients were reviewed for the relevant parameters before, during and after cementation. Each patient was classified as having no BCIS (grade 0) or BCIS grade 1,2, or 3 depending on the severity of hypotension, hypoxia loss of consciousness. Results: A total of 92 patients with complete data sets could be included in the study. The mean age was 83 years. 43 patients (Group A) were treated with a 2nd and 49 patients (Group B) with a 3rd generation cementing technique. The incidence of BCIS grade 1,2, and 3 was significantly higher (p = 0,036) in group A (n = 25; 58%) compared to group B (n = 17; 35%). Early mortality was higher in group A (n = 4) compared to group B (n = 0). Conclusions: BCIS is a potentially severe complication with a significant impact on early mortality following cemented hemiarthroplasty of the hip for the treatment of proximal femur fracture. Using a modified 3rd generation cementing technique, it is possible to significantly reduce the incidence of BCIS and its associated mortality.

Periodontal damage after thermal inhalation injury - The impact of high temperature inhalation injury on long term periodontal health

PURPOSE

Thermal inhalation injury is a common, life-threatening problem in burned patients. Whether or not this single event of damage to the oral integrity causes long term health problems is yet to be examined.

MATERIAL AND METHODS

All consecutive burn patients between 2014 and 2017 of Marienhospital Stuttgart (MHS), Germany, with at least 10% of burned skin surface were included and compared. The Periodontal Screening Index as well as Vitamin D levels were examined. Vitamin D has been suspected to contribute to the genesis of periodontitis. Risk factors and subjective oral life quality were prompted.

RESULTS

We included a total of 32 patients, 15 of which had an inhalation injury in their medical history. Risk factors were examined via Renatus' questionnaire. While risk factors were equally distributed in both groups we saw a remarkable difference in periodontal integrity, with the Periodontal Screening Index (PSI) per sextant differing drastically (with inhalation injury: 2.40, without inhalation injury: 1.10, p < 0.001). Patients with an inhalation injury had a mean of 5.2 out of 6 possible sextants with a pathologic PSI (with the median being 6/6), while patients without an inhalation injury had a mean of 1.83 out of 6 (median: 1/6), p < 0.001. The oral health impact profile showed a difference as well, albeit without statistical significance (with inhalation injury: median = 11, without: median = 3.5, p = 0.414). A correlation between Serum Vitamin D levels and periodontal integrity could not be seen in this group.

CONCLUSION

Inhalation injury is a possible cause for periodontitis and hence impacts the quality of life of burned patients.

Increased Geriatric Treatment Frequency Improves Mobility and Secondary Fracture Prevention in Older Adult Hip Fracture Patients-An Observational Cohort Study of 23,828 Patients from the Registry for Geriatric Trauma (ATR-DGU)

Interdisciplinary orthogeriatric care of older adult hip fracture patients is of growing importance due to an ageing population, yet there is ongoing disagreement about the most effective model of care. This study aimed to compare different forms of orthogeriatric treatment, with focus on their impact on postoperative mobilization, mobility and secondary fracture prevention. In this observational cohort study, patients aged 70 years and older with a proximal femur fracture requiring surgery, were included from 1 January 2016 to 31 December 2019. Data were recorded from hospital stay to 120-day follow-up in the Registry for Geriatric Trauma (ATR-DGU), a specific designed registry for older adult hip fracture patients. Of 23,828 included patients from 95 different hospitals, 72% were female, median age was 85 (IQR 80–89) years. Increased involvement of geriatricians had a significant impact on mobilization on the first day (OR 1.1, CI 1.1–1.2) and mobility seven days after surgery (OR 1.1, CI 1.1–1.2), initiation of an osteoporosis treatment during in-hospital stay (OR 2.5, CI 2.4–2.7) and of an early complex geriatric rehabilitation treatment (OR 1.3, CI 1.2–1.4). These findings were persistent after 120 days of follow-up. Interdisciplinary treatment of orthogeriatric patients is beneficial and especially during in-patient stay increased involvement of geriatricians is decisive for early mobilization, mobility and initiation of osteoporosis treatment. Standardized treatment pathways in certified geriatric trauma departments with structured data collection in specific registries improve outcome monitoring and interpretation.

The Association Between Orthogeriatric Co-Management and Mortality Following Hip Fracture

BACKGROUND

To meet the special needs of older patients with fragility fractures, models for collaborative orthogeriatric care have been developed. The objective of our study was to analyze the association of orthogeriatric co-management with mortality following hip fracture in older patients in Germany.

METHODS

This observational study was based on health insurance claims data from 58 001 patients (79.4% women) aged ≥80 years admitted to the hospital with hip fracture between January 2014 and March 2016. They were treated in 828 German hospitals with or without orthogeriatric co-management. The outcome measure was cumulative mortality with adjustment of the regression analyses.

RESULTS

The crude 30-day mortality was 10.3% for patients from hospitals with orthogeriatric co-management and 13.4% for patients from hospitals without orthogeriatric co-management. The adjusted 30-day mortality was 22% lower for patients in hospitals with orthogeriatric co-management (rate ratio 0.78; 95% CI [0.74; 0.82]; adjusted absolute difference -2.48%; 95% CI [-2.98; -1.98]). The difference in 30-day mortality remained nearly unchanged over the first 6 months. The risk reduction with orthogeriatric co-management was consistently observed in both women and men, across age groups, and in patients with and without care needs. The mean length of the index stay was 19.8 days in hospitals with orthogeriatric co-management and 14.4 days in hospitals without orthogeriatric co-management.

CONCLUSION

A multidisciplinary orthogeriatric approach is associated with lower mortality and a longer index stay in hospital after hip fracture.

[Treatment of patients with fragility fractures]

BACKGROUND

Fragility fractures are fractures in multimorbid, geriatric patients. Currently, their number is already high and is likely to increase in the future.

OBJECTIVE

This article gives an overview of the principles in the management of patients with fragility fractures.

MATERIAL AND METHODS

A selective literature review was performed to describe the epidemiology and relevance of fragility fractures. In addition, the principles of the perioperative management and surgical treatment of patients with fragility fractures are shown.

RESULTS

Due to the significant number of comorbidities, the treatment of patients with fragility fractures represents an interdisciplinary challenge. Ideally, treatment should be carried out in an interdisciplinary team under the leadership of orthopedic surgeons and geriatricians. Treatment should be based on consensus guidelines, which have been adapted to the local circumstances. Attention should be paid to some special aspects of the surgical treatment in this vulnerable patient cohort. Important are optimal soft tissue management, cement augmentation procedures and joint replacement in cases of periarticular fractures.

CONCLUSION

There is evidence that with optimal care the treatment of patients with fragility fractures can be significantly improved.

[Results of the pilot phase of the Age Trauma Registry DGU®]

BACKGROUND

Since 2014, hospitals with ortho-geriatric fracture centres could be certified as AltersTraumaZentrum DGU® in Germany. To measure the quality of treatment in these centres, a geriatric trauma registry (AltersTraumaRegister DGU®) was established.

OBJECTIVES

The aim of this work was to report the results of the pilot phase of the AltersTraumaRegister DGU® from the year 2015.

MATERIALS AND METHODS

Included were 118 patients >70 years with hip fracture or implant-related femoral fractures. Apart from other parameters, the point of surgery, initiation of anti-osteoporotic treatment and the EQ-5D one week post-surgery was measured.

RESULTS

Surgery was performed in 87% of patients within 24 h. Specific osteoporotic therapy could be increased from 4 to 63 patients. The EQ-5D was strongly restricted to one week post-surgery.

CONCLUSION

Based on the timing of surgery and anti-osteoporotic therapy, the treatment seems to be successful in the ortho-geriatric fracture centres. For a better evaluation of treatment quality in the AltersTraumaZentren DGU®, implementation of follow-up examinations in the AltersTraumaRegister DGU® is essential.

[Geriatric trauma centers from the idea to implementation. What has been achieved?]

The geriatric trauma working party, a subgroup of the German Society of Trauma Surgery (Deutsche Gesellschaft für Unfallchirurgie, DGU), focuses on the challenges of geriatric fractures, which are steadily increasing due to demographic changes. Inherent comorbidities implicate perioperative complications leading to loss of mobility and endangered independence followed by an increased burden on the social services. An interdisciplinary approach is required. The geriatric trauma working party defined criteria for interdisciplinary treatment and comprehensive care as well as early rehabilitation in interdisciplinary geriatric fracture centers. By passing an independent audit process these centers can achieve certification as a geriatric trauma center DGU (AltersTraumaZentrum DGU). Certified centers can participate in a recently established geriatric fracture registry which includes an internationally consented data set. Audit and registry enable centers to acquire an international benchmark, ensure permanent improvement in quality and allow participation in health services research.

Mono- versus polyaxial locking plates in distal femur fractures: a prospective randomized multicentre clinical trial

PURPOSE

Treatment of complex fractures of the distal femur utilizing monoaxial locking plates (e.g. Less Invasive Stabilisation System, LISS®, Synthes) is considered to be superior to conventional plating systems. Due to the limitation that the thread forces the screw into pre-determined positions, modifications have been made to allow screw positioning within a range of 30° (Non Contact Bridging, NCB®-DF, Zimmer). For the first time, this multicenter prospective randomized clinical trial (RCT) investigates the outcome of LISS® vs. NCB®-DF treatment following complex fractures of the distal femur.

METHODS

Since June 2008, 27 patients with a fracture of the distal femur (AO ASIF 33-A-C and periprosthetic fractures) were enrolled in this study by four university trauma centres in southern Germany. Clinical (e.g. range of motion, Oxford knee score, Tegner score) and radiological (e.g. axis deviation, secondary loss of realignment) follow-ups were conducted one and six weeks, as well as three, six, and 12 months after the operation.

RESULTS

This study comprises data of 27 patients (8 male, 19 female; 15 NCB®-DF, 12 LISS®). Polyaxial osteosynthesis using the NCB® system tended to result in better functional knee scores and a higher range of motion. Interestingly, fracture union tended to be more rapid using the polyaxial plating system.

CONCLUSIONS

We present the analysis of a multicenter prospective RCT to compare the monoaxial LISS® vs. the polyaxial NCB®-DF treatment following complex fractures of the distal femur. NCB®-DF treatment tended to result in better functional and radiological outcomes than LISS® treatment.

LEVEL OF EVIDENCE

Level I.

Exchange reamed nailing compared to augmentation compression plating leaving the inserted nail in situ in the treatment of aseptic tibial non-union: a two-centre study

BACKGROUND

A remarkable number of investigations are available treating tibial non-unions by exchange reamed nailing (ERN). Only few authors reported positive results after augmentation compression plating (ACP) for the same entity. To our knowledge no systematic study is published comparing ERN vs. ACP, so that this trial compares ACP leaving the already inserted un-reamed nail in situ against ERN in the treatment of aseptic tibial non-union, analysing success rate, time for union and operation time.

PATIENTS AND METHODS

Forty-eight patients with aseptic hypertrophic diaphyseal tibial non-union treated previously by un-reamed nailing were included retrospectively in this two-centre study. Group A consisted of 25 patients with ERN and group B of 23 patients with ACP leaving the underlying un-reamed nail in situ.

RESULTS

Mean follow-up was 3.8 years. Union was achieved in 24 out of 25 cases (96 %) for group A and in 22 out of 23 cases (95.6 %) for group B. Time needed for union varied; an average of 29 weeks for group A and 14 weeks for group B. The mean operation time for group A was 99 min, while it was 65 min for group B.

CONCLUSIONS

ERN and ACP with remaining pre-existing nail in situ are both safe and straightforward surgical procedures with equivalent high success rates of about 95 %. ACP has the advantage of less time for union and operating time in this series, but is associated with the disadvantage of requiring an additional incision and complaints associated to the plate requiring implant removal.

Early orthogeriatric treatment of trauma in the elderly: a systematic review and metaanalysis

BACKGROUND

More than 125,000 hip fractures occur in Germany every year, with a one-year mortality of about 25%. To improve treatment outcomes, models of cooperation between trauma surgery and geriatrics have been developed. Their benefit has not yet been unequivocally demonstrated.

METHODS

We systematically searched the Medline database and the Cochrane Library for prospective randomized controlled trials in which the treatment of elderly patients with fractures by the trauma surgery service alone was compared with preoperatively initiated collaborative treatment by the trauma surgery and geriatric services ("orthogeriatric" treatment). We investigated three treatment outcome variables--length of hospital stay, in-hospital mortality, and one-year mortality--in a metaanalysis.

RESULTS

The five trials of hip fracture treatment that met the selection criteria all had relatively small study populations and a high risk of bias. The outcomes with respect to hospital stay differed greatly among trials (I(2): 88.5%), and geriatric intervention was not found to have any statistically significant effect (0.06 days, 95% confidence interval [CI]: -3.74 to 3.62 days). The relative risk of dying in the hospital was 0.66 for orthogeriatric treatment (95% CI: 0.28-1.55, p = 0.34), and the hazard ratio for one-year mortality was 0.79 in favor of orthogeriatric treatment (95% CI: 0.57 to 1.10, p = 0.17). A metaanalysis of functional outcomes was not possible.

CONCLUSION

Only a few randomized controlled trials of early orthogeriatric treatment have been performed, and these trials are of limited quality. Due to low case numbers, a benefit from interdisciplinary orthogeriatric treatment could not clearly be demonstrated. Further trials are needed.

[Development of a catalogue of undergraduate learning objectives for orthopaedics and traumatology]

BACKGROUND

The developments towards a combined specialty of orthopaedic and trauma surgery requires not only the consolidation and revision of the postgraduate education training programme but also the development of a catalogue of learning objectives as a uniform basis for undergraduate medical training in the new specialty at German medical schools and teaching hospitals.

MATERIALS AND METHODS

Based on the Frankfurt Catalogue of Learning Objectives for Trauma Surgery and the Ulm Catalogue of Learning Objectives for Orthopaedics, a task force of experts has developed a combined catalogue of learning objectives for the new specialty. The experts of both specialties classified the learning objectives into 2 levels for knowledge, into 4 grades of competence for skills, as well as attitudes and social competence.

RESULTS

The general part of the operative specialties contains 120 items classified into 39 learning objectives for knowledge and 83 for skills. Two learning objectives comprise both knowledge and skill. The part orthopaedic and trauma surgery comprises 141 learning objectives, six items for skills, 138 for knowledge, as well as three learning objectives for both knowledge and skills. In addition, 22 learning objectives deal with aspects of attitudes and social competence.

CONCLUSION

In spite of the only recent alliance of orthopaedics and trauma surgery, the commission has developed not only a collection of topics, but also a usable joint catalogue of learning objectives for undergraduate training with a nationwide recommendation character. The catalogue paves the way for a forward-looking, modern education. The integrated recommendations for the prioritisation, the linkage to other subjects and specialties, and the integration of didactic methods facilitate the local implementation of the learning objectives without loosing any academic freedom.

The role of C5a in the innate immune response after experimental blunt chest trauma

The inflammatory response after severe blunt chest trauma often leads to acute lung injury and acute respiratory distress syndrome which are associated with high mortality rates. Whereas the role of innate immunity in acute lung injury has been broadly investigated, the immune response after blunt chest trauma is still poorly understood. Therefore, the role of complement and neutrophils was determined in bilateral lung injury induced by a single blast wave. The following time-points were investigated posttrauma: sham, 1, 6, 12, and 24 h. There was a time-dependent systemic activation of complement as determined by CH-50 and presence of C5a-dependent chemotactic plasma activity. Moreover, factor H, a complement regulatory protein, was increased systemically and locally after injury. Anti-C5a treatment immediately after trauma ameliorated these peaks. After an initial systemic leukopenic phase, a marked leukocytosis occurred. The latter was normalized by C5a blockade. In parallel, white blood cell count in bronchioalveolar lavage fluids was increased as a function of time and was significantly decreased by anti-C5a treatment. Trauma-induced lung injury was also associated with dramatic changes in neutrophil function, namely early enhanced chemotaxis and phagocytosis, followed by prolonged functional defects-all of which were ameliorated by anti-C5a treatment. Furthermore, blockade of C5a ameliorated the buildup of the proinflammatory cytokine TNF-alpha, diminished the increase of cytokine-induced neutrophil chemoattractant 1, and altered the levels of the anti-inflammatory cytokine IL-10. These data suggest that blunt chest trauma leads to systemic activation of complement and robust C5a generation, which causes perturbations in defensive functions of neutrophils. Thus, C5a might represent a potential target for therapeutic immunomodulation to prevent immune dysfunctions post-trauma and thereby, perhaps, the progression to acute respiratory distress syndrome.

[Injury prevention as the physician's challenge]

In Germany, more than 9 million individuals yearly sustain injuries and more than 30,000 fatal injuries. Based on estimations, preventive measures could avoid more than one half of all accidents and could influence the other half of the accidents such that the injuries caused are minor. The aim of an initiative of the Study Group on Injury Prevention of the German Trauma Society (DGU) is a complete inventory of all prevention programs from different expert groups in Germany. A synopsis of the gathered knowledge should serve as a basis for further interdisciplinary preventive measures. The consistent interdisciplinary orientation of this program is a special characteristic including trauma surgery, orthopedics, pediatric surgery, pediatrics, sociology, legal medicine, psychology, sports medicine, geriatrics, anesthesiology, and others. Special attention was also directed to the age groups of children/adolescents and the elderly.

[Fatal outcome after multiple trauma. The thoracic injury as the decisive factor]

In patients suffering from multiple injury, chest trauma is often the main cause of fatality. A case report is given and the literature reviewed.A 49 years old motorcyclist hit a car frontally in a road accident. After primary stabilization and first clinical care, he was transferred to our trauma centre because of severe chest injury, suspected pericardial effusion and lesion of the thoracic aorta. Initial diagnostics (plain radiographs, CT scan of thorax, abdominal ultrasound, echocardiography) showed left-sided serial rib fractures, a fracture of the left scapula, a hematopneumothorax left-sided, bilateral lung contusion, a small pneumothorax of the right side, a minimal pericardial effusion and a small splenic hematoma. The patient was treated in the intensive care unit, and the situation was initially stable. After 12 h, respiration deteriorated and a bronchoscopy showed filling of the airways with mucous fluid. The CT scan showed a worsening of the pulmonary damage and increasing pericardial fluid compression. A pericardiotomy was carried out, but the situation remained unstable. The patient was treated with invasive ventilation (PEEP>10, FiO2>0,5). Sudden severe bleeding out of left lower lobe was managed by thoracotomy and lobectomy. The patient remained unstable and died 95 h after the accident. This case shows that the severity of chest trauma does not necessarily correlate with the initial clinical and radiological findings. Even with all diagnostic and therapeutic procedures, a fatal outcome could not be prevented. This demonstrates the role of chest injury as a major and unforeseeable cause of death in multiple trauma patients.

The influence of stiffness of the fixator on maturation of callus after segmental transport

The treatment of large bony defects by callus distraction is well accepted, but the duration of treatment is long and the rate of complications increases accordingly. We have examined the effect of the stiffness of the axial fixator on reducing the time for maturation of callus.

We created a mid-diaphyseal defect of 15 mm in the metatarsal bone in sheep and stabilised it with a ring fixator. After four days a bony segment was transported for 16 days at 1 mm per day. After 64 days the animals were divided into four groups, three with axial interfragmentary movement (IFM) of 0.5, 1.2 and 3.0 mm, respectively, and a control group.

The 3.0 mm IFM group had the smallest bone density (p = 0.001) and area of callus and the largest IFM after 12 weeks; it also had typical clinical signs of hypertrophic nonunion. The most rapid stiffening of the callus was in the 0.5 mm group which had the smallest IFM (p = 0.04) after 12 weeks and radiological signs of bridging of the defect. These results indicate that suitable dynamic axial stimulation can enhance maturation of distraction callus when the initial amplitude is small, but that a large IFM can lead to delayed union.

[Correction of complex deformities in infectious conditions]

Skeletal deformities do occur after conservative or operative fracture treatment, as a consequence of congenital growth disturbance and as sequlae after posttraumatic and haematogenous osteomyelitis. In postinfectious deformities the course of the bone and soft tissue infection plays a decisive role when choosing the appropriate operative technique. Even in non active situations with a closed soft tissues envelope and no draining sinus persistence of germs within the bone has to be anticipated. The biological quality of the bone and the soft tissue envelope is often reduced because of local changes and as a result of multiple local revisions. Consequently wide areas of scar tissue and sclerotic bone are often encountered. The apex of the deformity is in most cases identical with the focus of the active or non active infection. The correction of the deformity at the apex can therefore only be accomplished if the infectious bone is also resected. If a correction is not possible at the apex of the deformity, translation at the osteotomy site is necessary to achieve a correct mechanical axis. The later rather complex operative procedure necessitates intensive preoperative planning and an extensive experience with deformity corrections by external fixators.

The influence of stiffness of the fixator on maturation of callus after segmental transport

The treatment of large bony defects by callus distraction is well accepted, but the duration of treatment is long and the rate of complications increases accordingly. We have examined the effect of the stiffness of the axial fixator on reducing the time for maturation of callus. We created a mid-diaphyseal defect of 15 mm in the metatarsal bone in sheep and stabilised it with a ring fixator. After four days a bony segment was transported for 16 days at 1 mm per day. After 64 days the animals were divided into four groups, three with axial interfragmentary movement (IFM) of 0.5, 1.2 and 3.0 mm, respectively, and a control group. The 3.0 mm IFM group had the smallest bone density (p = 0.001) and area of callus and the largest IFM after 12 weeks; it also had typical clinical signs of hypertrophic nonunion. The most rapid stiffening of the callus was in the 0.5 mm group which had the smallest IFM (p = 0.04) after 12 weeks and radiological signs of bridging of the defect. These results indicate that suitable dynamic axial stimulation can enhance maturation of distraction callus when the initial amplitude is small, but that a large IFM can lead to delayed union.

[Correction of post-traumatic diaphyseal malalignment of the lower extremity]

Post-traumatic deformities do occur as a result of disturbed fracture healing with loss of bone stock, necrosis of fragments or the development of pseudarthrosis resulting in malunion or progressive malalignment. In the majority of the cases these disturbances can be related to technical problems of primary fracture treatment like insufficient reduction or implant failure. On the other hand, complex deformities with involvement of the adjacent joints may also be a result of injuries of the growth plate in childhood. In some cases primary correction is impossible because of critical conditions of the bone and the soft tissue envelope in the center of deformation. If a secondary correction is indicated, knowledge of all reconstructive techniques is essential to choose the appropriate method and carry out successful and exact correction of malalignment of the affected limb after detailed planning.

[Occupational disease 2108. Degeneration pattern in magnetic resonance tomography of the lumbar spine in patient with differential weight-bearing activity]

The addition of vertebral disc degeneration to the job-related disease register raises the question of vertebral disc degeneration patterns according to loading strain. The readings of the lumbar vertebra of construction workers and nurses were compared with those of a group without workload. In the groups examined, aged 35 to 50, monosegmental damage was found in only 17% of the patients with high workload, as opposed to 29% of those with no workload, mostly with monosegmental damage at level L5/S1. Damage to the upper segments of the lumbar spine with intact discs in between was found exclusively in patients with high workload. Multiple segment damage in the age range examined was found in subjects with activities that add to the load of the spinal column. The value of MRI in assessing and evaluating illness originating from the vertebral discs is currently being discussed.