Sex Differences in Serum C-Reactive Protein Course after Total Hip Arthroplasty

Background

Gender-specific medicine has become an important part in investigating the course of various diseases. C-reactive protein (CRP) is used as an inflammatory marker for detecting inflammations and even infections after total hip arthroplasty (THA). The general course of CRP after THA is well known, but there is controversy about its association with sex. Therefore, we aimed to investigate if there is an influence of sex on the CRP after THA in the first 10 days after operation in a complication-free course in male and female patients and to re-evaluate the specific postoperative CRP course with its maximum on the second to third postoperative days.

Methods

We retrospectively reviewed patients who had been treated with THA due to primary osteoarthritis through the same approach using an equal model of a cementless stem and a cup and complication-free between 2013 and 2016. Patients with active inflammation, rheumatoid arthritis, secondary arthrosis, active cancer disease, and documented postoperative complications were not included. The CRP values before THA and up to 10 days after THA were recorded and tested for sex discrepancy. Factor analyses were performed, and CRP values were adjusted for confounders (age, operation time, diabetes mellitus, and body mass index [BMI]).

Results

A total of 1,255 patients (728 women and 527 men) were finally analyzed. Men were younger and had a longer operation time and a higher BMI compared to women. The prevalence of overweight was higher in men, while obesity (BMI > 40 kg/m²), diabetes mellitus, renal failure, and American Society of Anaesthesiologists status showed no significant difference between men and women. Men had significantly higher CRP values than women between the 2nd and the 7th postoperative days, with the largest difference on the 4th postoperative day (men, 130.48 mg/L; women, 87.26 mg/L; p = 0.018).

Conclusions

Based on the results of more precise sex-specific evaluation of the postoperative CRP course after THA, the present study showed for the first time that there was a gender discrepancy in the CRP course after complication-free THA in the first 7 postoperative days. Furthermore, this study confirmed the postoperative CRP course with its maximum on the third postoperative day.

[Patient safety during endoprosthetic training : Does the training of surgeons in primary hip arthroplasty at certified endoprosthesis centres lead to increased complications?]

Hintergrund

Ziel der Studie war die Untersuchung, ob sich das perioperative Outcome und operationsspezifische Prozessgrößen bei Patienten mit Hüftgelenksersatz signifikant verschlechtern, wenn die Operation durch einen unerfahrenen Operateur, assistiert durch einen erfahrenen Operateur, im Kontext eines zertifizierten Endoprothesenzentrums durchgeführt wird.

Material und Methoden

Es wurden 1480 Patienten eingeschlossen, die zwischen 2013 und 2016 bei primärer Koxarthrose mit einer primären zementfreien Hüfttotalendoprothese (HTEP) versorgt wurden. Die relevanten Daten wurden retrospektiv aus dem Krankenhausinformationssystem, dem Entlassungsbrief und aus dem EndoCert-Bogen dokumentiert. Die Operateure wurden nach ihrer Qualifikation in erfahrene (Senior, > 50 HTEP pro Jahr) und unerfahrene Operateure (Junior, < 50 HTEP pro Jahr) unterteilt. Anschließend erfolgte der Vergleich der erhobenen Daten anhand dieser Unterteilung.

Resultate

Es zeigte sich bei unerfahrenen Operateuren eine signifikante Verlängerung der Operationsdauer um 20,7 min (Senior 62,6 ± 20,4 min; Junior 83,3 ± 19,5 min; p ≤ 0,001), der Krankenhausverweildauer um 0,25 Tage (Senior 8,8 ± 0,9 d; Junior 9,0 ± 0,9 d; p ≤ 0,001) und eine Erhöhung der Transfusionshäufigkeit von Erythrozytenkonzentraten (Senior 0,6 ± 1,1 Stk.; Junior 0,9 ± 1,4 Stk.; p ≤ 0,001). Dagegen zeigte sich kein Unterschied bei perioperativen Komplikationen (p = 0,682) und beim perioperativen Blutverlust (Senior 1,3 ± 0,5 l; Junior 1,3 ± 0,5 l; p = 0,097). Zwischen Operationsdauer und Blutverlust bestand allerdings eine positive Korrelation (Senior r = 0,183; Junior r = 0,214; jeweils p ≤ 0,01).

Schlussfolgerung

Die Ausbildung von unerfahrenen Operateuren an einem zertifizierten Endoprothesenzentrum führt bei Assistenz durch erfahrene Operateure nicht zur Reduktion der Patientensicherheit mit vermehrten Komplikationen. Aufgrund der Operationszeitverlängerung kommt es allerdings zu einer Mehrbelastung der Kliniken im Wettbewerb mit nichtausbildenden Kliniken, die nicht im DRG-System abgebildet ist.

Psychological distress and health-related quality of life in patients with bone marrow edema syndrome

BACKGROUND

The aim of the study was to investigate psychological distress and health-related quality of life (HrQoL) in patients with bone marrow edema syndrome (BMES) of the hip or knee joint.

METHODS

This retrospective study included patients with the diagnosis BMES treated in the period 2016-2017. As well as analyzing the epidemiological data (age, sex, vascular disease, hypertension, etc.), we used the Hospital Anxiety and Depression Scale (HADS) to document anxiety and depression and the five-level version of the EuroQol Group's EQ-5D instrument (EQ-5D-5L) to assess HrQoL and compared it to historical controls of the healthy population.

RESULTS

The study group comprised 56 patients (26 females, 30 males) with a mean age of 55.8 (range, 15-84) years. HADS: there was no difference between the study and control cohorts in the rates of anxiety (P=0.595) or depression (P=0.241). EQ-5D-5L: the HrQoL was significantly lower in the patients with BMES than in the healthy controls both for parameters of the EQ-5D-5L index and in the various age groups. No difference in HrQoL was seen between BMES of the hip and the knee or among the different radiological stages of BMES.

CONCLUSIONS

The patients with BMES displayed a clear reduction in HrQoL, but this was not associated with psychological distress with regard to significant anxiety and depression. Patients with BMES and a high score for anxiety and depression are at great risk of chronic pain, and we recommend they should receive psychological counseling.

[Complications and costs in primary knee replacement surgery in an endoprosthetics centre : Influence of state of training]

BACKGROUND

This work examines the hypothesis that in endoprosthesis implantation there are differences between experienced primary and senior caregivers (S-Op) and less experienced follow-up assistants (T-Op) with respect to process-relevant parameters. The main hypothesis is that compared to S‑Op, T‑Op cause significantly longer surgery times and thus additional operating theatre costs. As sub-hypotheses, differences in various perioperative (p-o) parameters between T‑Op and S‑Op were examined.

MATERIALS AND METHODS

The status of the operator (senior and/or senior main operator [S-Op]) and/or postoperative CRP, perioperative blood loss, the amount of transfused erythrocyte concentrates, patient age, gender, ASA risk classification (American Society of Anesthesiologists), duration of surgery and blood transfusion, duration of inpatient stay, as well as the rates of early revision surgery and complications were recorded. A comparison of patients who had been operated by an S‑Op and those who had been operated by a T‑Op was made for all parameters.

RESULTS

Significant differences were found with respect to the duration of surgery, the duration of the hospital stay, and CRP on the third p‑o day. The T‑Op required an average of 11 min more than the S‑Op. CRP was significantly higher in the T‑Op group only on the third p‑o day, by 18 mg/l. In contrast, in the T‑Op group, a blood loss of 181 ml was lower than in the S‑Op group. This corresponded to a reduction of 0.26 transfused erythrocyte concentrates. There were no significant differences in complication rates between S‑Op and T‑Op.

DISCUSSION

In the setting of a certified endoprosthetics centre, the comparison of T‑Op with S‑Op showed that the use of the former with at a non-increased complication rate led to a significant extension of the operating time. This leads to additional training costs in the amount of an estimated 3% of the current DRG remuneration. These additional costs are not represented adequately in the current remuneration system.

Patient Obesity Influences Pelvic Lift During Cup Insertion in Total Hip Arthroplasty Through a Lateral Transgluteal Approach in Supine Position

BACKGROUND

Movement of the pelvis during implantation of total hip arthroplasty (THA) has a major influence on the positioning of the acetabular cup. Strong traction caused by retractors leads to iatrogenic pelvic lift and can thus be partly responsible for cup malpositioning. The objective of this study was to investigate such factors that influence pelvic lift.

METHODS

The dynamic movement of the pelvis was measured during implantation of THA in 67 patients. This was done by measuring the acceleration using the SensorLog app on a smartphone.

RESULTS

At its maximum, the pelvis was lifted by an average of 6.7°. When impacting the press-fit cup, the surgical side was raised by 4.4° compared with the time of skin incision. This lift at the time of cup implantation correlates significantly with the body mass index and the patient's abdominal and pelvic circumference.

CONCLUSION

Every surgeon performing THA must be aware of the pelvic lift during an operation. Especially in patients with a high body mass index, a large abdominal circumference, or a large pelvic circumference, there is an increased risk of malpositioning of the acetabular cup. When impacting the cup, we recommend releasing the traction of the retractor, so that the pelvis can tilt back into its natural position, and thus, the anticipated cup positioning can be implemented as exactly as possible.

C-reactive protein course during the first 5 days after total knee arthroplasty cannot predict early prosthetic joint infection

INTRODUCTION

Periprosthetic joint infection (PJI) is one of the most devastating major complications after total knee arthroplasty (TKA). The laboratory value C-reactive protein (CRP) is the inflammatory biomarker most suitable for detecting a potential postoperative (p.o.) early infection in orthopaedic surgery. However, on the basis of multiple receiver operating characteristic (ROC) analyses, CRP only has limited sensitivity and specificity. The objective of the present study was to test the hypothesis that, besides the absolute preoperative CRP value, also the absolute postoperative CRP value and its course over the first 5 days after TKA are valid indicators of periprosthetic early infection.

MATERIALS AND METHODS

A total of 1068 subjects who had been treated with a unilateral primary cemented total knee replacement due to primary osteoarthritis of the knee were included in the study. Retrospectively, for all patients, the preoperative CRP value, the p.o. CRP course and a history of the medical course, including any superficial surgical site infection (SSI) or deep PJI of the knee joint operated on, were recorded; further, any follow-up operations (septic revision) were documented. Using receiver operating characteristic (ROC) analysis, an optimum preoperative CRP cutoff value for the positive prediction of a PJI was determined.

RESULTS

34 of 1068 patients developed an SSI or a PJI that had to be revised. After TKA implantation, the CRP value increased significantly and achieved its maximum between the second and third p.o. day. At no p.o. day was there a difference in CRP between patients who developed an SSI or a deep PJI and patients with a normal complication-free p.o.

COURSE

In contrast, the preoperative CRP value proved to be a reliable predictor for septic revision due to an SSI or a PJI: the ROC analysis showed the optimum preoperative CRP cutoff value for a positive prediction of PJI to be 5 mg/L.

CONCLUSION

The most important finding of the present study is that neither the absolute p.o. CRP value nor its course in the first 5 days after TKA is suitable for detecting an early infection. In contrast, an increased preoperative CRP value proved to be a valid predictor for septic revision due to an SSI or a PJI after TKA.

Influence of Surgical Approach on Pelvic Lift in Hip Arthroplasty During Cup Insertion

The position of the acetabular cup is a major factor in the long-term outcome of total hip arthroplasty (THA). Malpositioning of the acetabular cup frequently has been reported with the use of a minimally invasive implantation technique. It remains unclear whether the limited visibility or the increased retractor traction and thus tilting of the pelvis during cup implantation is the cause. This study investigated the influence of iatrogenically related pelvic lift using an anterolateral minimally invasive THA technique. In a group of 30 consecutive patients who underwent THA via a minimally invasive anterolateral approach, iatrogenic lifting of the pelvis was measured with a smartphone using a 3-axis accelerometer and compared with patients in a historical age- and sex-matched control group who underwent THA using a transgluteal approach. Postoperatively, the inclination and anteversion of the cup was determined on pelvic radiographs. In the anterolateral group, the pelvis was lifted by a maximum of 6.3° and by an average of 3.9° when the acetabular cup was impacted; no difference was noted compared with the transgluteal group. In contrast, the cups in the anterolateral group showed significantly increased inclination and reduced anteversion. In both techniques, the iatrogenic tilting of the pelvis at the time of cup implantation occurred to a comparable extent. Therefore, the significant differences in postoperative radiographs cannot be attributed to increased retractor traction on exposure of the acetabulum, which means that the limited visibility must be responsible. [Orthopedics. 2017; 40(4):e589-e593.].

Changes of posterior condylar offset results in midflexion instability in single-radius total knee arthroplasty

INTRODUCTION

There is no algorithm for the management of joint stability in midflexion up to now. Change in the joint line (JL) is considered to be the primary cause, although it only determines the extension gap. The purpose of this study was to determine the influence of the posterior condylar offsets (PCO), which defines the flexion gap, on midflexion instability.

MATERIALS AND METHODS

Forty-two knee joints (38 patients) were included in this study, patients undergoing navigated total knee arthroplasty due to primary osteoarthritis of the knee. Changes in the JL and the PCO were determined from the navigation data. A gap tensioning device was used to determine the width of the joint gap at -5°, 0°, 30° and 60° intraoperatively.

RESULTS

Within a range between 5 mm proximalization and 2 mm distalization, the JL had no influence on stability in midflexion. In contrast to this, both an increase and a decrease in PCO led to midflexion instability (R = 0.361, p = 0.019). In 16 cases (38%), the PCO was changed by more than 2 mm. This led to a midflexion instability of more than 2 mm in seven of these cases (44%).

CONCLUSIONS

Whereas the joint line can be displaced by up to 5 mm without measurable changes in joint stability, reconstruction of the posterior offset within a tight range of 2 mm is necessary to avoid midflexion instability.

The C-reactive protein level after total knee arthroplasty is gender specific

PURPOSE

Laboratory diagnostics are part of the routine before and after operations. In all specialist surgical disciplines, including orthopaedic surgery, the acute-phase protein CRP is used to detect inflammatory processes, especially infections. The potential influence of patient gender on the postoperative course of CRP after TKA implantation is still unclear. In order to achieve a more precise evaluation of the complication-free general CRP course after TKA, the objective of the present study is to test the hypothesis that the p.o. course and level of CRP is gender specific in the first 10 days after TKA.

METHODS

A total of 1068 consecutive patients who had been treated with a unilateral primary cemented total knee replacement due to primary osteoarthritis of the knee over a 36-month period were retrospectively included in the study. For all patients, the preoperative CRP value and the postoperative course of CRP from postoperative days 1-10 were recorded and tested for gender specificity.

RESULTS

On days 2-5 and 7-8 after surgery, men had significantly higher CRP values than women. The maximum difference was 45 mg/L on the fourth p.o. day (men 170 mg/L, women 125 mg/L, p = 0.019).

CONCLUSION

The present study was able to show, for the first time, that the complication-free course of CRP in the first 10 days after TKA implantation is gender specific. The impact of the finding on diagnostic is that the gender-specific CRP course provides a more precise evaluation of the complication-free course of CRP after TKA. These results have clinical relevance to the interpretation of postoperative CRP values in order to avoid unnecessary investigations such as puncture or surgical care in female and male patients with uncomplicated TKA. Level of evidence Diagnostic study, III.

Effects of Kinesio taping compared to arterio-venous Impulse System™ on limb swelling and skin temperature after total knee arthroplasty

PURPOSE

It is an established fact that post-operative (p.o.) soft-tissue swelling and lymphoedema after total knee arthroplasty (TKA) have a major influence on the p.o. early functional outcome. Kinesio taping has a proven clinical effect in increasing lymph drainage. Despite the decades of experience gained and the assumed positive effects, hardly any investigations have been conducted to date on the influence of Kinesio taping on the p.o. healing process after TKA. The objective of the present study was to test the hypothesis that Kinesio taping used as a lymph application leads to a reduction of p.o. soft-tissue swelling. As a secondary objective, it was to be tested whether there is an effect on skin temperature as a surrogate parameter for dermal micro-circulation.

METHODS

In this prospective study with a historical control (A-V Impulse System™ group), 42 subjects were included and treated with Kinesio taping after implantation of a TKA. The patients of the study group were treated immediately p.o. with Kinesio® Tex Gold™ fan cut tape as a lymph application with a common base. A thermographic temperature determination of the knee joint operated on was performed on each patient in the supine position every day from the first to the seventh p.o. day. The leg circumference was documented daily at eight specified measuring points on both lower limbs. As a statistical analytical approach, the so-called principal component analysis was used. An analysis of variance was performed. The significance level was set at p < 0.001.

RESULTS

The course of soft-tissue swelling of the study group did not differ from that of the control group at any point in time. For the temperature course of the medial wound aspect, no difference was seen between the Kinesio taping study group and the A-V Impulse System™ group. In contrast, the temperature course of the lateral wound aspect showed a reproducibly higher temperature in the Kinesio tape group than in the control group (0.6 °C (0.5-0.8), p < 0.001).

CONCLUSION

The hypothesis of the study that Kinesio taping as a lymph application induces a reduction of soft-tissue swelling after TKA must be rejected on the basis of the present data. Solely the temperature of the lateral wound aspect was higher in the Kinesio taping group than in the control group, so that an increased blood circulation can be assumed here. Considering that the actively working A-V Impulse System™ used in the control group also increases local blood circulation, the effect of the passive Kinesio tape is surprising. However, this was not reflected in a quicker wound healing, as the day of last wound secretion was the same in both groups. Kinesio taping as a lymph application represents an equivalent alternative to the A-V Impulse System™ for therapy after total knee arthroplasty with regard to soft-tissue swelling and wound healing.

The reversed gap technique produces anatomical alignment with less midflexion instability in total knee arthroplasty: a prospective randomized trial

PURPOSE

No surgical technique is capable of controlling the stability of the joint in midflexion. The purpose of the present study was to present and evaluate a surgical technique that aims to reduce the need for soft-tissue release and optimize stability in midflexion.

METHODS

Sixty knee joints were included in this prospective randomized study. Surgery was performed either according to a classical gap (GT) technique or using the reversed gap (RG) technique. In the RG, the femoral component was positioned parallel to the surgical transepicondylar axis using a preoperative MRI and a navigation system. The frontal alignment of the tibia was then selected to produce a symmetric flexion gap. Then, the frontal alignment of the femoral component was adjusted to produce a symmetric extension gap. Soft-tissue release was defined to be extensive if more than two steps or stabilizing structures were involved. Joint stability was measured at different flexion angles (-5° to 120°) using a gap tensioning device and the trial femoral implant.

RESULTS

In the GT group, 16 knee joints (53 %) showed an instability of more than 2 mm at 5°, 30° or 60°, compared with 8 knee joints (27 %) in the RG group (p = 0.035). The RG did not lead to a reduction in the number of soft-tissue releases, but they were less extensive.

CONCLUSION

RG reduced midflexion instability and the number of extensive soft-tissue releases. It may simplify the operation by reducing the extent of soft-tissue releases and avoid instability-related problems of knee arthroplasty. Nevertheless, it should only be performed under controlled conditions until long-term clinical data are available.

LEVEL OF EVIDENCE

I.

Morbidly Obese Patients Undergoing Reduced Cup Anteversion Through a Direct Lateral Approach

BACKGROUND

The presence of obesity negatively affects the results after total hip arthroplasty. The influence of morbid obesity on cup positioning is investigated.

METHODS

A retrospective analysis of radiographs from 790 patients in 2013 and 2014 was performed. The correlation of cup inclination and anteversion with body mass index (BMI) was analyzed. Three groups were formed: 139 patients with normal weight (BMI of <25 kg/m(2)), 566 patients with moderate obesity (BMI between 25 and 34 kg/m(2)), and 85 patients with morbid obesity (BMI of ≥35 kg/m(2)).

RESULTS

Cup anteversion significantly correlated with BMI (R = -0.127, p < 0.001) and patient age (R = 0.115, p = 0.001). This corresponded with a reduction of anteversion by 3.4° (p < 0.001) in the morbidly obese group compared with the normal-weight group. Cup inclination was not influenced by BMI or patient age.

CONCLUSIONS

The precision of cup positioning declines with increasing obesity. In addition, significantly reduced anteversion is found in younger patients. We assume that this is due to iatrogenically changed pelvic tilt resulting from increased pressure exerted on the dorsal and ventral acetabular rim retractors.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

The volume of the human knee joint

INTRODUCTION

Despite its clinical relevance, particularly in septic knee surgery, the volume of the human knee joint has not been established to date. Therefore, the objective of this study was to determine knee joint volume and whether or not it is dependent on sex or body height.

METHODS

Sixty-one consecutive patients (joints) who were due to undergo endoprosthetic joint replacement were enrolled in this prospective study. During the operation, the joint volume was determined by injecting saline solution until a pressure of 200 mmHg was achieved in the joint.

RESULTS

The average volume of all knee joints was 131 ± 53 (40-290) ml. The volume was not found to be dependent on sex, but it was dependent on the patients' height (R = 0.312, p = 0.014). This enabled an estimation of the joint volume according to V = 1.6 height - 135.

CONCLUSIONS

The considerable inter-individual variance of the knee joint volume would suggest that it should be determined or at least estimated according to body height if the joint volume has consequences for the diagnostics or therapy of knee disorders.

Unsatisfactory outcome of arthrodesis performed after septic failure of revision total knee arthroplasty

BACKGROUND

Periprosthetic infection is one of the most dreaded orthopaedic complications. Current treatment procedures include one-stage or two-stage revision total knee arthroplasty. If the periprosthetic infection is no longer controllable after several revision total knee arthroplasties, many surgeons regard knee arthrodesis as a promising option. The aim of our study was to ascertain whether intramedullary nailing results in the suppression or eradication of an infection and to identify risk factors for persistent infection.

METHODS

All patients who had undergone intramedullary nailing following septic failure of revision total knee arthroplasty between 1997 and 2013 were included in the study. Pathogens, risk factors predisposing to persistent infection, and the rate of persistent infections were recorded. In addition, a visual analog scale (VAS) and Knee injury Osteoarthritis Outcome Score (KOOS), Knee Society Score (KSS), Lysholm, Short Form-36 (SF-36), and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) questionnaires were completed to assess clinical outcomes and quality of life.

RESULTS

Twenty-six patients were included in the study. Thirteen (50%) had a persistent infection requiring additional revision surgery. Nineteen patients (73%) reported persistent pain (VAS score of >3). All scores showed marked impairment of quality of life.

CONCLUSIONS

Intramedullary nailing following septic failure of revision total knee arthroplasty must be regarded with skepticism, and we cannot recommend it. Repeat revision total knee arthroplasty or amputation should be considered as an alternative in such difficult cases.

[The post-traumatic arthritis - a challenge?]

Total knee replacement in patients with post-traumatic arthritis is not fundamentally different from total knee replacement in patients with primary arthritis. Because of a 10-times higher infection rate, ordinary surgical planning should be implemented by the best possible exclusion of site infection based on actual information. Extra-articular deformities have to be preoperatively identified and individually treated with either an incomplete or a complete intra-articular correction or a single or double correction osteotomy. The commonly found combination of a contracted knee joint and an insufficient ligament balancing can mask instabilities of the knee joint. Consequently the definitive grade of a constrained knee prosthesis can only be determined intraoperatively. Existing osseous defects can be addressed with autologous bone grafts left from the total knee arthroplasty. Depending on the osseous defective site and the grade of constraints, prosthesis stems may be necessary but so far no clear recommendation can be given for either a cemented or a cementless fixation of the stem. The approach to the knee joint should be guided according to existing scars in order to prevent wound healing disorders. Even given optimal surgical planning and an optimum procedure of total knee arthroplasty postoperative results of post-traumatic arthritis are significantly inferior to results of primary arthritis. Therefore it is important to induce the commonly younger patients to form realistic expectations.

Human osteoblast damage after antiseptic treatment

PURPOSE

Antiseptics are powerful medical agents used for wound treatment and decontamination and have a high potential for defeating joint infections in septic surgery. Both chlorhexidine and polyhexanide are frequently used in clinical practice and have a broad antimicrobial range, but their effect on human osteoblasts has not been sufficiently studied. Our objective was to investigate the toxic effects of polyhexanide and chlorhexidine on human osteoblasts in vitro to evaluate their clinical applicability in septic surgery.

METHODS

We isolated and cultivated human osteoblasts in vitro and assayed the toxic effects of chlorhexidine 0.1% and polyhexanide 0.04%, concentrations commonly applied in clinical practice. Toxicity analysis was performed by visualisation of cell structure, lactate dehydrogenase (LDH) activity and evaluation of vital cells. Toxicity was evaluated by microscopic inspection of cell morphology, trypan blue staining and determination of LDH release.

RESULTS

Damaged cell structure could be shown by microscopy. Both antiseptics promoted LDH activity after incubation with osteoblasts. The evaluation of vital osteoblasts showed a significant decrease of vital cells.

CONCLUSIONS

Both antiseptics induced significant cell death of osteoblasts at optimum exposure. We therefore recommend cautious use of polyhexanide and chlorhexidine in septic surgery to avoid severe osteoblast toxicity.

Invasive electromagnetic field treatment in osteonecrosis of the femoral head: a prospective cohort study

Introduction :

The purpose of this prospective cohort study was to compare the surgical treatment of non-ONFH in adulthood by curettage and bone grafting with treatment by curettage and bone grafting in combination with invasive electromagnetic field treatment using Magnetodyn^®. This was assessed by examining whether electromagnetic field treatment has a positive additive effect on the clinical parameters modified Harris Hip Score according to Haddad, Cook and Brinker, Merle d'Aubigné hip score and visual analogue scale, and on the subsequent need for treatment by total hip arthroplasty.

Materials and Methodology :

The prospective, non-randomised study included 35 patients with unilateral or bilateral osteonecrosis of the femoral head. These were divided into two groups according to the surgical treatment regime and assessed over a 12-month follow-up period. The study group (Group 1) comprised 19 patients (14 men and 5 women) with a total of 22 non-ONFH, who underwent minimally invasive curettage, bone grafting and electromagnetic field treatment (Magnetodyn^®) by implantation of a bipolar induction screw. The control group (Group 2) comprised 16 patients (12 men and 4 women) with a total of 18 non-ONFH, who underwent minimally invasive curettage and bone grafting without Magnetodyn^® therapy. At the initial pre-operative examination and the 6 and 12-month follow-up, all patients were assessed by clinical examination and radiological monitoring, and by bilateral hip MRI. The clinical evaluation was based on the modified Harris Hip Score according to Haddad, Cook and Brinker, the Merle d`Aubigné hip score and the visual analogue scale (VAS).

Results :

At the time of follow-up, total hip arthroplasty (THA) had been performed in four patients in Group 1 (18%). In Group 2, four patients (22%) had received a THA (n.s.). Both procedures led to an improvement in the clinical scores (Harris Hip Score, Merle d`Aubigné score and VAS), although no significant difference was observed.

Conclusion :

The authors conclude that electromagnetic field treatment with Magnetodyn^®, using the special signal protocol applied here, as an adjunct to curettage and autologous bone grafting to treat non-ONFH, does not produce better clinical results and does not offer better prophylaxis for the avoidance of total hip arthroplasty over all ARCO stages.

[Joint swelling, reversible arm paresis, and elevated serum IgG4 in a 55-year-old man]

Only described in the last 10 years, IgG4-related disease is a fibroinflammatory disorder characterized by tumorous lesions with dense lymphoplasmacytic infiltration by IgG4-positive plasma cells and often elevated concentration of serum IgG4. In this paper, we present a male patient with this disease involving the lymph nodes and possibly the joints and kidneys. Infiltration of lymph node tissue with IgG4-positive plasma cells was demonstrated. The general condition of the patient improved considerably by immunosuppressive therapy.

Osteodensitometry measurements of periprosthetic bone using dual energy X-ray absorptiometry following total knee arthroplasty

INTRODUCTION

The present study investigates the reaction of bone density as well as the possible factors influencing this reaction following a cement-free total knee arthroplasty (TKA).

MATERIALS AND METHODS

Osteodensitometry scan data from 50 prospective patients with TKA was evaluated. The patients were split into two groups according to the number of follow-up investigations undertaken. No patient included in the study had received medication to increase bone density. To identify the changes in periprosthetic bone density, dual energy X-ray absorptiometry (DXA) bone density measurements in defined regions of interest (ROI) were performed over a period of 24 months postoperative. The test parameters included gender, severity of arthrosis, as well as the metric parameters T-score, body mass index, cortical bone marrow index, and the varus alignment for the respective patient.

RESULTS

The most significant changes in bone density were recorded within the first 3 months postoperative, in particular, the highest bone density loss was found in the region of the proximal medial tibia. Moreover, significant gender-specific associations regarding changes in bone density were established.

CONCLUSION

Finally, results achieved in the present study demonstrate that the fundamental classification in defined ROI proved to be functional and effective.

Opening-wedge high tibial osteotomy with a locked low-profile plate: surgical technique

BACKGROUND

High tibial osteotomy has been recognized as a beneficial treatment for osteoarthritis of the medial compartment of the knee. The purpose of this prospective study was to assess the short-term results of opening-wedge high tibial osteotomies with locked plate fixation.

METHODS

From September 2002 to November 2005, fifty-one consecutive medial opening-wedge high tibial osteotomies were performed. The mean age of the patients at the time of the index operation was forty-nine years. The preoperative and postoperative factors analyzed included the grade of arthritis of the tibiofemoral compartment (the Ahlbäck radiographic grade), the anatomic tibiofemoral angle, patellar height, the Hospital for Special Surgery rating system score, and the Lysholm and Gillquist knee score.

RESULTS

Postoperatively, one superficial wound infection occurred. Fifty of the fifty-one osteotomies healed after an average period of 12.9 weeks (range, eight to sixteen weeks) without bone grafts. A nonunion developed in a sixty-two-year-old patient who was a cigarette smoker. The average postoperative tibiofemoral angle was 9° of valgus. Forty-nine patients were followed for a mean of fifty-two months. The average score on the Hospital for Special Surgery rating system was 86 points at the time of the most recent follow-up. The rating was excellent in twenty-eight patients (57%), good in twelve (24%), fair in four (8%), and poor in five (10%). The average score on the Lysholm and Gillquist knee-scoring scale was 83 points. According to these scores, the outcome was excellent in nine patients (18%), good in thirty-one (63%), fair in three (6%), and poor in six (12%). Four knees failed after an average of thirty-six months.

CONCLUSIONS

Our results suggest that an opening-wedge high tibial osteotomy with locked plate fixation allows a correct valgus angle to be achieved with good short-term results.

Pneumatic compression with foot pumps facilitates early postoperative mobilisation in total knee arthroplasty

Deep-vein thrombosis (DVT) and pulmonary embolism (PE) represent life-threatening postoperative complications frequently responsible for in-hospital mortality following total knee arthroplasty (TKA). Mechanical prophylaxis in the form of a foot pump offers an alternative to pharmacological and physical therapy. The aim of this prospective and randomised study was to examine the clinical efficacy of the A-V Impulse (AVI) system in reduction of soft-tissue swelling of the lower limb following a TKA. A total of 80 patients undergoing cemented TKA between September 2005 and December 2006 were randomised into two groups of 40 patients (n¹ = 40, n² = 40) during the 16-month study period. All patients received a subcutaneous dose of low molecular weight heparin (LMWH) (Enoxaparin/Clexane® 40 mg) once daily beginning 24 hours prior to the operation. The mean age for the groups n¹ and n² were 68.93 and 68.15 years, respectively. The reduction of soft-tissue swelling in the n¹ group was significantly higher (p < 0.05) compared with n². Evaluation of body mass index (BMI) with regard to the average reduction of soft-tissue swelling showed no significant influence (p < 0.05). The better function of the operated knee in group AVI was a significant predictor for improved agility and mobility (p < 0.01). No complications were reported for the application of the AVI. No ultrasonographic evidence of DVT or PE was found in any of the 80 patients during the investigative time period of eight days. After three months, there was no evidence of a symptomatic DVT.

Opening-wedge high tibial osteotomy with a locked low-profile plate

BACKGROUND

High tibial osteotomy has been recognized as a beneficial treatment for osteoarthritis of the medial compartment of the knee. The purpose of this prospective study was to assess the short-term results of opening-wedge high tibial osteotomies with locked plate fixation.

METHODS

From September 2002 to November 2005, fifty-one consecutive medial opening-wedge high tibial osteotomies were performed. The mean age of the patients at the time of the index operation was forty-nine years. The preoperative and postoperative factors analyzed included the grade of arthritis of the tibiofemoral compartment (the Ahlbäck radiographic grade), the anatomic tibiofemoral angle, patellar height, the Hospital for Special Surgery rating system score, and the Lysholm and Gillquist knee score.

RESULTS

Postoperatively, one superficial wound infection occurred. Fifty of the fifty-one osteotomies healed after an average period of 12.9 weeks (range, eight to sixteen weeks) without bone grafts. A nonunion developed in a sixty-two-year-old patient who was a cigarette smoker. The average postoperative tibiofemoral angle was 9 degrees of valgus. Forty-nine patients were followed for a mean of fifty-two months. The average score on the Hospital for Special Surgery rating system was 86 points at the time of the most recent follow-up. The rating was excellent in twenty-eight patients (57%), good in twelve (24%), fair in four (8%), and poor in five (10%). The average score on the Lysholm and Gillquist knee-scoring scale was 83 points. According to these scores, the outcome was excellent in nine patients (18%), good in thirty-one (63%), fair in three (6%), and poor in six (12%). Four knees failed after an average of thirty-six months.

CONCLUSIONS

Our results suggest that an opening-wedge high tibial osteotomy with locked plate fixation allows a correct valgus angle to be achieved with good short-term results.

The condylar plate for treatment of distal femoral fractures: a long-term follow-up study

The aim of this retrospective study was to present the long-term functional and radiological outcomes of indirect reduction techniques and fixation with a condylar plate for treatment of distal femoral supracondylar or intracondylar femoral fractures. The series included 24 men and 17 women, mean age 51 years, between March 1994 and April 1999. All fractures were AO type 33, and eight were open fractures. Primary iliac bone graft was used in five cases. In one case of severe osteoporosis, screw fixation was augmented with cement. There were three delayed unions, one non-union and two infections; four participants required reoperation with bone grafts. Two (5%) participants developed a second varus deformity and three a second valgus deformity; correction osteotomy with bone grafts was necessary in these cases. After a mean follow-up of 9.5 years, the mean Neer score was 82 points and indicated that function was excellent in 16, satisfactory in 9, unsatisfactory in 4 and poor in 2 cases. The mean Neer score in cases of isolated fracture was 89 points and in cases with additional injuries was 72 points. Thus the long-term results of indirect reduction techniques of distal femoral fractures treated with the condylar plate were good to excellent in 82% of cases.

Nuclear accumulation and homeostasis of the unusual polymer beta-poly (L-malate) in plasmodia of Physarum polycephalum

The plasmodium of Physarum polycephalum specifically contains an unusual polyester, beta-poly(L-malate), which is not found in any of the mononucleate forms of its life cycle. Plasmodia growing on D-glucose have been analyzed for beta-poly(L-malate) in nuclei, cytosol and culture medium after cell fractionation, purification by chromatography on DEAE-cellulose and digestion of proteins/nucleic acids. Nuclei contained 400 micrograms polymer per 1 g of plasmodia, corresponding to a nuclear concentration of 230 mM L-malyl residues, not depending on growth rates, lengths of growth periods, and the growth form as micro- or macroplasmodia. The synthetic rate increased during the phase of rapid enlargement of the nuclei after mitosis. Beta-Poly(L-malate) was polydisperse in molecular mass, these tending to be higher in nuclear than in cytosolic extracts and being lowest in the culture medium. Beta-Poly(L-malate) was not degraded when contained in plasmodia, in contrast to degradation and the occurrence of low molecular mass polymer in the culture medium. During pulse-chase feeding with D-[14C]glucose (0.8 micrometerCi/mol), beta-[14C]poly(L-malate) appearance followed kinetics indicating a release of polymer from nuclei into the culture medium when it was in excess of a threshold. Injection experiments with purified beta-[14C]poly(L-malate) revealed a re-entry from the cytoplasm into the nuclei and thus the possibility of commutation between the cytoplasm and the nuclei. The observed homeostasis in nuclei supports the assumption that beta-poly(L-malate) plays an essential role in growing plasmodia.

DNA polymerase alpha--primase complex of Physarum polycephalum

DNA polymerase alpha and DNA polymerase alpha--primase complex of Physarum polycephalum were purified by rapid methods, and antibodies were raised against the complex. In crude extracts, immune-reactive polypeptides of 220 kDa, 180 kDa, 150 kDa, 140 kDa, 110 kDa, 86 kDa, 57 kDa and 52 kDa were identified. The structural relationships between the 220 kDa, 110 kDa and 140 kDa (the most abundant form) was investigated by peptide mapping. The 140 kDa form was active DNA polymerase alpha. The 57 kDa and the 52 kDa polypeptides were identified as primase subunits by auto-catalytic labelling. In amoebae, the immune-reactive 140 kDa polypeptide was replaced by a 135 kDa active DNA polymerase alpha.

Specific inhibition of Physarum polycephalum DNA-polymerase-alpha-primase by poly(L-malate) and related polyanions

Poly(L-malate) is an unusual polyanion found in nuclei of plasmodia of Physarum polycephalum. We have investigated, by enzymatic and fluorimetric methods, whether poly(L-malate) and structurally related polyanions can interact with DNA-polymerase-alpha-primase complex and with histones of P. polycephalum. Poly(L-malate) is found to inhibit the activities of the DNA-polymerase-alpha-primase complex and to bind to histones. The mode of inhibition is competitive with regard to DNA in elongation and noncompetitive in the priming of DNA synthesis. Spermidine, spermine, and histones from P. polycephalum and from calf thymus bind to poly(L-malate) and antagonize the inhibition. The polyanions poly(vinyl sulfate), poly(acrylate), poly(L-malate), poly(D,L-malate), poly(L-aspartate), poly(L-glutamate) have been examined for their potency to inhibit the DNA polymerase. The degree of inhibition is found to depend on the distance between neighboring charges, given by the number of atoms (N) interspaced between them. Poly(L-malate) (N = 5) and poly(D,L-malate) (N = 5) are the most efficient inhibitors, followed by poly(L-aspartate) (N = 6), poly(acrylate) (N = 3), poly(L-glutamate) (N = 8), poly(vinyl sulfate) (N = 3). It is proposed that poly(L-malate) interacts with DNA-polymerase-alpha-primase of P. polycephalum. According to its physical and biochemical properties, poly(L-malate) may alternatively function as a molecular chaperone in nucleosome assembly in the S phase and as both an inhibitor and a stock-piling agent of DNA-polymerase-alpha-primase in the G2 phase and M phase of the plasmodial cell cycle.