Utility of histopathological examination in aseptic revision total hip arthroplasty: a preliminary analysis

INTRODUCTION

The utility of a routine histopathological examination in aseptic revision total hip arthroplasty (THA) has not been well explored. We aim to describe the approach and present the results of histopathological examination, focusing on its clinical usefulness in the setting of aseptic revision THA.

METHOD

We retrospectively reviewed 285 performed aseptic revision THA with available histopathological reports between 2015 and 2017 at a single institution. We described histopathological requests by the surgical team. Preoperative diagnoses, intraoperative findings, as well as histopathology and culture results were analysed.

RESULTS

13 painful THAs (4.5%) had preoperatively unknown diagnoses. In 10 of them, potential causes of pain were intraoperatively identified. Histopathology confirmed these findings in 8 THAs. 19 THAs (6.7%) revealed unexpected positive cultures (UPC). Histopathology was negative for infection in 18 of them. Among 16 consultants, 3 surgeons requested histopathology in 47% of the cases (130/285), usually to exclude infection (101/285; 35%). Documentation for tissue sample location was lacking in 51% (145/285), and for question asked by the surgeon in 47% (135/285).

CONCLUSIONS

Histopathology is deemed a useful confirmatory tool in the context of ruling out infection in UPCs, and in documenting intraoperative findings in painful THAs with unknown preoperative diagnoses. Importantly, the approach to requesting histopathology should be optimised. Further large-scale studies, including cost analyses, are warranted to explore the usefulness of histopathology in routine utility.

What Is the Impact of Automated Synovial Cell Counting on Different Aseptic Causes and Periprosthetic Conditions Associated With Revision THA?

BACKGROUND

Studies have suggested that automated synovial cell counting may overestimate the white blood cell (WBC) count, resulting in false positive tests when evaluating patients for the possibility of periprosthetic joint infection (PJI) after THA. However, associations between WBC counts high enough to mimic PJI in patients whose arthroplasties are not infected but rather are experiencing a variety of aseptic problems-including but not limited to metallosis, polyethylene wear, and recurrent dislocation-have not, to our knowledge, been adequately addressed. In addition, there is a lack of analyses about the polymorphonuclear percentage (PMN%) when assessed by automated analyzers in this context.

QUESTIONS/PURPOSES

In the context of different indications for aseptic revision and different periprosthetic hip pathologic findings, we asked: (1) What were the synovial WBC count levels, and what proportion of values were above the 2018 International Consensus Meeting (ICM) cutoff (3000 cells/μL)? (2) What were the synovial PMN% levels, and what proportion of values were above the 2018 ICM (70%)?

METHODS

We retrospectively studied the preoperative cell count analyses of synovial fluid in patients who underwent revision THA for aseptic reasons at our tertiary referral arthroplasty center between January 2015 and December 2017. We considered all revisions performed on patients during that time potentially eligible, and after prespecified exclusions were applied (exclusions mainly included 15% [197 of 1306] sporadic missing data and 12% [155 of 1306] insufficient synovial fluid obtained in the aspirate), a total of 702 patients undergoing revision THA for aseptic reasons remained for the final analysis. As far as we know, no patients underwent re-revision for PJI at a mean follow-up of 46 ± 11 months, which tends to confirm our impression that indeed these hips did not have PJI. Cell count analyses were conducted using an automated analyzer. Clinical findings, preoperative radiographs, and surgical reports--confirmed by available histologic results--were used to establish diagnoses. We evaluated these hips considering the recommendations of the 2018 ICM (WBC count of 3000 cells/μL and PMN% of 70%) to see what proportion of them would have been characterized as likely having PJI on basis of those cutoff values. The mean WBC count for the entire cohort was 2120 ± 2395 cells/μL. The mean PMN% for the entire cohort was 36% ± 22%.

RESULTS

Compared with aseptic loosening and recurrent dislocation, polyethylene wear had the highest mean WBC count (3817 ± 3711 cells/μL; p < 0.001). Of the investigated periprosthetic conditions, wear-induced synovitis had the highest value (4464 ± 3620 cells/μL; p < 0.001). Considering the ICM threshold, polyethylene wear showed the highest proportion of WBC counts above 3000 cells/μL among the indications for aseptic revision (60% [25 of 42]; p < 0.001). Of the periprosthetic conditions, wear-induced synovitis showed the highest proportion beyond the ICM cutoff (60% [50 of 83]; p < 0.001). The mean PMN% for aseptic causes ranged between 28% and 44% without differences among them (p = 0.12). Patients with metallosis had the highest mean PMN% of the periprosthetic conditions investigated (45% ± 25%; p = 0.007). Regarding the ICM threshold, metallosis resulted in the largest proportion of patients with a PMN% above 70% (21% [10 of 47]; p = 0.003), and that for wear-induced synovitis was 6% (5 of 83; p = 0.42) and for osteolysis was 3% (1 of 33; p = 0.51). There were no differences among aseptic loosening, recurrent dislocation, and polyethylene wear in terms of the proportion above 70% among the aseptic revision causes.

CONCLUSION

Using automated cell counting, we found that WBC counts differ widely across indications for aseptic revision THA, and a high proportion of patients who underwent revision THA for aseptic reasons had WBC counts above the commonly used threshold of 3000 cells/μL. However, the PMN% was much less affected in several common indications for aseptic revision THA, making this measure more reliable for interpreting aspiration results using an automated analyzer. Based on the data distributions we observed, manual counting techniques might be considered in particular among patients with polyethylene wear, metal-on-metal bearing surfaces, or suspected metallosis. However, an elevated WBC count alone, observed using an automated analyzer in the context of polyethylene wear, should not be considered to be strongly suggestive of PJI, since that finding occurred so commonly among patients without infection.

LEVEL OF EVIDENCE

Level III, diagnostic study.

High Rate of Reinfection With New Bacteria Following One-Stage Exchange for Enterococcal Periprosthetic Infection of the Knee: A Single-Center Study

BACKGROUND

A wide range of success rates following the surgical management of enterococcal periprosthetic joint infection (PJI) with a tendency toward worse outcomes have been reported. However, the role of 1-stage exchange remains under-investigated. Therefore, we aimed to evaluate our results after the 1-stage knee exchange for enterococcal PJI.

METHODS

Forty patients were retrospectively included between 2002 and 2017 with a mean follow-up of survivors of 80 months (range 22-172; standard deviation [SD] = 5). Polymicrobial infections occurred in 45% (18/40) of patients. Patients' characteristics, joint-related data, and antibiotic therapy were recorded. Rates of enterococcal infection relapse, reinfection with new microorganisms, and re-revision for any reason were determined. Bivariate analysis was conducted to identify risk factors of infection recurrence.

RESULTS

Revision surgery was required in 22 cases (55%) with a mean time to revision surgery of 27 months (range 1-78; SD = 25). Indications for aseptic revisions (18%) included aseptic loosening (10%), periprosthetic fracture (5%), and patellar instability (3%). The most common cause of re-revision was a subsequent PJI (15/22; 68%) after a mean time of 22 months (range 1-77; SD = 24). Overall infection recurrence rate was 37.5% (15/40), substantially due to entirely non-enterococcal infections (9/15; 60%). Infection relapse with Enterococci occurred in 4 cases (10%) within 16 months postoperatively. Older patients (P = .05) and male gender (P = .05) were associated with a higher risk of infection recurrence.

CONCLUSION

Overcoming the Enterococci using the 1-stage exchange for knee PJI is achievable but the rate of reinfection due to new microorganisms is high . However, the overall infection recurrence rate is comparable to other treatment approaches.

Revision Arthroplasty with Total Femur Replacement for the Management of Complex Post-traumatic Bone Defect in a Patient with Dwarfism

Dwarfism leads to an early onset of osteoarthritis of the joints of the lower limb. Due to bone deformities, arthroplasty is challenging. The incidence of implant-associated complications is higher compared to the normal population and often ends up with multiple revision arthroplasties. We report the first case in the literature of a 48-year-old patient with dwarfism who required implantation of a custom-made total femoral replacement due to aseptic stem loosening and a concomitant valgus gonarthrosis.

Tibial plateau fracture: does fracture classification influence the choice of surgical approach? A retrospective multicenter analysis

PURPOSE

The role of classification systems for the choice of surgical approach and the management of tibial plateau fractures remains unclear. The purpose of this study was to investigate the potential of classification systems to choose the appropriate operative approach. Current surgical management strategies were investigated in a large multicenter assessment.

METHODS

In this study, we retrospectively analyzed all patients with tibial plateau fractures that have received surgical treatment in one of the five Level I trauma facilities between 2012 and 2015. Fractures were classified in each center by a senior orthopedic surgeon using the AO/OTA and the Luo classification. Demographics, trauma mechanism, as well as the surgical approach were recorded.

RESULTS

538 patients (46.1% male, 53.9% female) were included. The anterolateral approach was used most frequently with 54.8% of all single approaches; 76.2% of all combined approaches used anterolateral as part of the approach. Combined approaches were used in 22.5% of the cases; a combination of the anterolateral and medial (10%), anterolateral, and posteromedial approach (5.8%) were used most frequently. The lowest number was found for the posterolateral (1.3%) and the combined approaches dorsal/anterolateral and medial/dorsal (1.7%, 1.1%). The AO/OTA classification showed a peak for 41.B2 (21.9%) and B3 (35.5%) fractures. Regarding the Luo classification, the dorsal column was involved in 45.7%. In contrast, only 14.7% of the surgical approaches used were able to address the dorsal tibial plateau potentially.

CONCLUSION

The use of dorsal approach seems to be of minor importance than expected in daily clinical practice in this multicenter study. It was not possible to specify whether the AO/OTA or the Luo classification can reliably predict the choice of surgical approach. The operative treatment strategy of tibial plateau fractures seems to rather rely on the surgeons' experience, education, and preferences.

An alternative treatment option for Paprosky Type IIIb acetabular defect using multiple tantalum wedges - A case report

The treatment of severe acetabular defects in revision total hip arthroplasty (Paprosky type IIIa and IIIb) is demanding and choosing the appropriate surgical technique remains controversial. The introduction of trabecular metal augments has led to a variety of new treatment options. The authors present a case of a Paprosky Type IIIb acetabular defect due to eight subsequent revisions of the left hip. The patient was treated with an alternative treatment option using multiple tantalum wedges. Anatomical reconstruction was achieved and at 12 months follow-up, the patient was pain free and was able to walk without walking aids.

Influence of a modified Nd:YAG laser treatment outside the visual axis on the morphology of Elschnig pearls

PURPOSE

To observe changes in posterior capsule opacification (PCO) after Nd:YAG treatment with and without opening the posterior lens capsule.

METHOD

This prospective randomized study included patients with regeneratory PCO. In substudy 1, a small low-energy Nd:YAG capsulotomy was performed (MiniYAG). In substudy 2, a low-energy Nd:YAG laser treatment without opening the lens capsule was performed (GentleYAG). Concerning analysis, in both substudies, the posterior capsule was divided into 4 quadrants and the quadrant where the Nd:YAG laser treatment was performed was randomly allocated. Change in PCO was analyzed using retroillumination images objectively (AQUA score: 0-10).

RESULTS

In total, 27 eyes of 25 patients were used for this study. In substudy 1, the mean amount of PCO (AQUA score) for the entire posterior capsule decreased significantly (p < 0.05, ANOVA) from 5.2 (SD: 1.6) before to 4.0 (SD: 1.9) immediately after the MiniYAG. In substudy 2, the mean amount of PCO (AQUA score) for the entire posterior capsule analyzed before and immediately after the GentleYAG was 5.1 (SD: 2.4) and 5.2 (SD: 2.3), respectively.

CONCLUSION

Performing a MiniYAG led to a significant PCO reduction. Gentle polishing of the posterior capsule resulted in a relevant reduction of PCO in one third of the patients.

Continuous blood pressure monitoring during exercise using pulse wave transit time measurement

This paper gives an overview of a research, which is focused on the development of the convenient device for continuous non-invasive monitoring of arterial blood pressure. The blood pressure estimation method is based on a presumption that there is a singular relationship between the pulse wave propagation time in arterial system and blood pressure. The parameter used in this study is pulse wave transit time (PWTT). The measurement of PWTT involves the registration of two time markers, one of which is based on ECG R peak detection and another on the detection of pulse wave in peripheral arteries. The reliability of beat to beat systolic blood pressure calculation during physical exercise was the main focus for the current paper. Sixty-one subjects (healthy and hypertensive) were studied with the bicycle exercise test. As a result of current study it is shown that with the correct personal calibration it is possible to estimate the beat to beat systolic arterial blood pressure during the exercise with comparable accuracy to conventional noninvasive methods.

[Avulsion of the inferior rectus muscle due to a dog-bite and reconstruction of its function]

BACKGROUND

Injuries of an extraocular muscle or of the globe due to a dog-bite are rare.

PATIENT

An 43-year-old patient presented with an orbital dog bite. He had a complete avulsion of the inferior rectus muscle. During the primary surgical repair, the proximal part of the muscle could not be found. The distal part of the inferior rectus muscle was sutured to the tissue in the original region of the retracted inferior rectus muscle. After surgical repair the patient could read without complaint. We explain the unexpected remarkable postoperative result on the basis of high resolution MRI: Although the muscle belly was lost, some parts of the muscle sheath forming connections to Tenon's capsule had remained. These allowed a certain function of the muscle.

CONCLUSIONS

If during the primary surgical repair of a traumatic avulsion of an extraocular muscle the proximal part of the muscle could not be found, it is worth to suture the distal part of the muscle to tissues (empty muscle sheath, connections to Tenon's capsule) in the original region of the lost muscle. This prevents a further retraction of the proximal part of the muscle and helps the finding and differentiation of the structures of the muscle during a prospectivly following surgical repair.

High-throughput scanning of the rat genome using interspersed repetitive sequence-PCR markers

We report the establishment of a hybridization-based marker system for the rat genome based on the PCR amplification of interspersed repetitive sequences (IRS). Overall, 351 IRS markers were mapped within the rat genome. The IRS marker panel consists of 210 nonpolymorphic and 141 polymorphic markers that were screened for presence/absence polymorphism patterns in 38 different rat strains and substrains that are commonly used in biomedical research. The IRS marker panel was demonstrated to be useful for rapid genome screening in experimental rat crosses and high-throughput characterization of large-insert genomic library clones. Information on corresponding YAC clones is made available for this IRS marker set distributed over the whole rat genome. The two existing rat radiation hybrid maps were integrated by placing the IRS markers in both maps. The genetic and physical mapping data presented provide substantial information for ongoing positional cloning projects in the rat.

T-cut in the bottom of the scleral pocket in combined cataract and glaucoma surgery

PURPOSE

To determine whether radial transsection of the inner lamina of the phaco tunnel (T-cut) allows intraocular pressure (IOP) control in cases of co-existing cataract and glaucoma and to evaluate the results of this glaucoma triple procedure.

SETTING

Department of Ophthalmology, Hanusch Hospital, Vienna, Austria.

METHODS

In a prospective study, a T-shaped incision in the tunnel floor was performed in 43 eyes (Group A); 48 eyes (Group B) had phacotrabeculectomy (phacoemulsification and trabeculectomy of a 3.0 x 2.0 mm tissue block).

RESULTS

At the end of a minimum follow-up of 24 months in Group A (range 24 to 30 months) and of 28 months in Group B (range 28 to 44 months), there was no significant difference in the extent of IOP reduction between groups. Intraocular pressure was well controlled (< or =20 mm Hg) without antiglaucoma therapy in 27 eyes (62.8%) in Group A and 30 (62.5%) in Group B. Eleven eyes (25.6%) in Group A and 14 (29.2%) in Group B achieved an IOP of 20 mm Hg or less with antiglaucoma therapy. Five eyes (11.6%) in Group A and 4 (8.3%) in Group B required surgical revision. Complications included hypotony (Group A, 5 eyes; Group B, 3 eyes), hyphema (Group A, 8 eyes; Group B, 6 eyes), malignant glaucoma (Group B, 1 eye), in-the-bag hematoma (Group B, 1 eye), and fibrin exudation (Group B, 1 eye).

CONCLUSION

Phacoemulsification with a T-cut in the tunnel floor was a safe and effective combined procedure and, in this regard, equivalent to phacotrabeculectomy.

Adjuvant polychemotherapy of nonorgan-confined bladder cancer after radical cystectomy revisited: long-term results of a controlled prospective study and further clinical experience

A total of 83 patients with nonorgan-confined bladder cancer with or without lymph node metastases (tumor stages pT3b, pT4a and/or pN1, pN2) was evaluated in November 1993 for relapse-free and overall survival. All patients underwent radical cystectomy between 1987 and 1991, 38 underwent adjuvant polychemotherapy with methotrexate, vinblastine and cisplatin plus doxorubicin (M-VAC) or epirubicin (M-VEC). Of the 83 patients 49 had entered a prospective randomized trial comparing adjuvant to no adjuvant treatment. The protocol was activated in May 1987. Patient recruitment was concluded in December 1990 because an interim analysis of the 49 randomized patients revealed a significant prognostic advantage in favor of the 26 patients randomized to the chemotherapy group compared to 23 in the control group (p = 0.0015, log-rank test for relapse-free survival curves). Preliminary data were published in 1992. Of the 26 patients randomized for adjuvant chemotherapy 18 were treated with M-VAC or M-VEC, 7 refused chemotherapy before or during cycle 1 and 1 received chemotherapy without cisplatin because of impaired renal function. The update of patient followup obtained in November 1993 continues to demonstrate a significant improvement in progression-free survival in favor of patients randomized for adjuvant chemotherapy (p = 0.0005). Followup of patients living free of disease ranged from 38 to 78 months. In a second analysis of actual treatment, the total collective of 83 patients treated from 1987 to 1991 was reviewed: 38 who had actually undergone adjuvant M-VAC/M-VEC (18 during the prospective trial and 20 in 1991 as the routinely recommended therapy) were compared with 45 without adjuvant M-VAC/M-VEC (7 refused to participate in the adjuvant trial, 8 randomized for but did not undergo adjuvant M-VAC/M-VEC, 23 belonged to the control group of the trial, and 7 underwent cystectomy in 1991 and remained without adjuvant treatment). This analysis again revealed a significant prognostic advantage in favor of the patients treated with adjuvant M-VAC/M-VEC. We conclude that adjuvant chemotherapy with M-VAC/M-VEC leads to a significant prolongation of relapse-free survival and to an improvement of the definitive cure rates after radical cystectomy for locally advanced transitional cell carcinoma of the bladder.

Benzodiazepines and other psychotropic drugs abused by patients in a methadone maintenance program: familiarity and preference

Physicians often face the problem that they have to treat anxiety and insomnia in patients who are dependent on narcotics or other substances. Reports about different reinforcing properties of different benzodiazepines and increasing concern about their misuse, often in combination with other drugs, call for studies that help to establish recommendations for choosing psychopharmacologic agents in the treatment of these patients. Opiate addicts enrolled in a methadone maintenance program were interviewed about their subjective "liking" of all psychotropic substances with which they had personal experience. The results confirm previous reports that certain benzodiazepines, especially flunitrazepam and diazepam, stand out from others in terms of positive reinforcing properties. Overall, the attractiveness of benzodiazepines as drugs of abuse for poly-drug abusers is lower than that of other sedative/hypnotics.