Are the long term results of a high-flex total knee replacement affected by the range of flexion?

Purpose

The purpose of this study was to examine the effect of deep flexion on the long-term durability of a high-flex ceramic implant in total knee arthroplasty.

Methods

Five hundred and five consecutive knees replaced with a Bi-Surface knee system (Kyocera Medical, Osaka, Japan) were divided into two groups according to the range of flexion by 135° postoperatively. Comparison of implant durability was made between the high- and low-flexion groups after a minimum ten year follow-up.

Results

With revision for any surgery as the end point, the survival rates at ten years were 95.5 % and 96.2 % in the high- and low-flexion group, respectively (p = 0.63). With revision for mechanical failure as the end point, survival rates were 98.7 % and 98.5 %, respectively (p = 0.94).

Conclusion

Implant survival rate was similar for both groups. Deep flexion seemed not to affect long-term durability.     

Accuracy of urine pH testing in a regional metabolic renal clinic: is the dipstick accurate enough?

Urine pH is a useful marker for assessing treatment need and efficacy in patients with nephrolithiasis. Though the gold standard of measurement is with a pH electrode, dipsticks offer the convenience of cost, ease of use, and the possibility of patients measuring their own values outside the clinic. The aim of this study was to determine whether dipsticks offer the same accuracy as the electrode. Paired measurements of freshly voided urine pH with both electrode and dipstick were analysed in a multidisciplinary renal clinic. We found that although there was a high Pearson correlation between the samples (0.89, p = 0.001), urine dipstick measurements carried an approximately 1 in 4 risk of producing clinically significant differences (pH differences  > 0.5 pH unit) from meter values. We also found that at high and low urine pH, the dipstick tended to over- and underestimate true pH readings, respectively. Examining the values in the 98 patients where a need for pharmacological urinary pH manipulation was indicated by the true pH, we found 14 who would not have been appropriately treated, and 5 who would have been unnecessarily medicated, if the stick pH value had been used. We conclude that dipstick pH measurement is insufficiently reliable for guiding clinical decision-making.     

Are nitrite/nitrate (NOx) levels elevated by inhalation injury?

The relationship between airway burn and nitric oxide (NO) levels in the early burn stage was investigated by quantifying nitrite/nitrate (NOx), which are the final metabolites of NO, in 22 burn patients. Although total body surface area (TBSA) and burn index (BI) were significantly higher in patients with airway-burn than in patients without airway burn (P=0.0347 and 0.0422, respectively), no significant difference in NOx levels was observed between the two groups (P=0.6196). The NOx levels were found to correlate significantly with TBSA (r=0.4775, P=0.0246). A significant correlation was also noted between the NOx levels and BI (r=0.4391, P=0.0409). These results suggest that NO reflects the intensity of inflammation in the early burn stage, but that excessive NO formation is unlikely to be induced by stress, such as that caused by airway burn.     

Friction burns within the tibia during reaming. Are they affected by the use of a tourniquet?

We have carried out a prospective, randomised trial to measure the rise of temperature during reaming of the tibia before intramedullary nailing. We studied 34 patients with a mean age of 35.1 years (18 to 63) and mean injury severity score of 10 (9 to 13). The patients were randomised into two groups: group 1 included 18 patients whose procedure was undertaken without a tourniquet and group 2, 16 patients in whom a tourniquet was used. The temperature in the bone was measured directly by two thermocouples inserted into the cortical bone near the isthmus of the tibial diaphysis. Reaming was carried out to at least 1.5 mm above the required diameter of the nail. Blood loss was assessed by recording the preoperative and postoperative haemoglobin (Hb) level. The minimum clinical follow-up was six months. In group 1 (no tourniquet), the mean Hb dropped 2.8 g/dl from 14.3 +/- 1.02 g/dl to 11.5 +/- 1.04 g/dl (p = 0.0001), whereas with the tourniquet, the mean decrease was 1.3 g/dl from 14 +/- 1 g/dl to 12.7 +/- 1.3 g/dl (p = 0.007). This difference was not statistically significant. The mean initial tibial temperature was 35.6 degrees C (SD 0.6) and rose with reaming to levels between 36.3 degrees C and 51.6 degrees C. The highest temperatures were obtained with the largest reamers (11 and 12 mm, p = 0.0001) and the most rapid rise with the smallest diameters of medullary canal (8 or 9 mm). The rise of temperature was transient (20 s). We were unable to identify any effect of the use of a tourniquet on the temperature achieved. Reamed intramedullary tibial nailing induces a transient elevation of temperature which is directly related to the amount of reaming.     

Does refrigeration of urine alter culture results in hospitalized patients with neurogenic bladders?

A prospective, blinded study of 40 hospitalized spinal cord injured (SCI) patients was conducted to evaluate the effects of refrigeration on urinalysis and culture results. Urine samples were divided, with one aliquot examined within 4 hours and the other after 24 hours of refrigeration. Comparisons using Wilcoxon Signed Rank analysis showed no significant difference between fresh and refrigerated samples in white blood cell (WBC) count (z = -0.353, p = 0.724), number of bacteria (z = -0.772, p = 0.440), leukocytes (z = -0.277, p = 0.782), or colony counts of E. fecalis, E. coli, Citrobacter, Pseudomonas, Streptococcus, Yeast, or Acinetobacter (z = -1.00, p = 0.317; z = 0.00, p = 1.0; z = 0.00, p = 1.0; z = 0.00, p = 1.0; z = -1.00, p = 0.317; z = 0.00, p = 1.0; z = 0.00, p = 1.0, respectively). A statistically significant difference between fresh and refrigerated samples was found with "mixed" organisms (z = -2.565, p = 0.010) and a difference approaching significance was found with Staph aureus (z = -1.841, p = 0.066), both with colony counts of less than 50 k. No changes in cultures or colony counts occurred following refrigeration that would have resulted in altered treatment regimens. This study indicates that refrigeration of urine samples for up to 24 hours in the hospital setting rarely causes changes in identified organism type and causes no clinically significant changes in urinalysis or urine culture results in SCI patients.     

Are lipid‐dependent indicators of cardiovascular risk affected by renal transplantation?

Hyperlipoproteinemia has been reported to frequently occur in kidney transplanted patients, thus possibly explaining, at least in part, the increased incidence of cardiovascular disease in this population. To evaluate the impact of renal transplantation (Tx), and related immunosuppressive therapy, on plasma lipoprotein and Lp(a) profile, we selected a cohort of kidney transplanted patients (36 M/14 F; age 33.8 + 12.0 yr, range 13-62) lacking significant causes of hyperlipidemia. All patients received a triple immunosuppressive regimen and showed a stable renal function after Tx (plasma creatinine: 1.36 +/- 0.35 mg/dL). One year after Tx, we found a significant increase of total cholesterol (TC), LDL, HDL, ApoB and ApoA-I (p < 0.005), while plasma triglyceride levels remained unmodified. Lp(a) plasma levels after Tx were within the normal range and displayed a significant inverse relationship with apo(a) size. Noteworthy, LDL/HDL ratio and ApoB/ ApoA-I ratio in kidney transplanted patients were almost superimposable with those of normal controls. Specifically, LDL/HDL ratio significantly decreased in 64% of patients after Tx, due to a prevalent increase of HDL, and was associated with a moderate amelioration of plasma TG. In a multiple linear regression model, post-Tx HDL level was significantly related to recipient's age, gender, BMI and cyclosporine (CyA) trough levels (Adj-R2 = 0.35, p = 0.0002), with gender and CyA trough levels being the better predictors of HDL. In conclusion, immunosuppressive regimens, in themselves, do not appear to significantly increase the atherogenic risk related to lipoproteins. Rather, other factors can affect the lipoprotein profile and its vascular effects in renal transplant recipients.     

Night-time polyuria and urine hypo-osmolality in enuretics identified by nocturnal sequential urine sampling--do they represent a subset of relative ADH-deficient subjects?

Early morning urine osmolality was tested in two urinary specimens, one taken immediately upon awakening and the other approximately 30 min thereafter, in 52 enuretic and 15 non-enuretic children. In a follow-up study, using the same study population, urine osmolality and volume were measured sequentially at 3-h intervals at 19.00, 22.00, 01.00, 04.00 and 07.00 h. Thereafter, all enuretics were treated by intranasal DDAVP for a 6-month period. There were no differences in urinary osmolality between enuretic and non-enuretic children when comparing the two early morning specimens. Nor were there any differences between groups in urine osmolalities at 19.00, 01.00 and 07.00 h. In contrast, at 04.00 h, urine osmolality was significantly lower in 17 of 52 enuretics [designated as ADH-negative (ADH-)] compared to the remaining enuretics [designated as ADH-positive (ADH+)] and non-enuretic children (610 +/- 251 vs 995 +/- 195 and 1089 +/- 195 mosmol/kg H2O, respectively, p < 0.05). This decreased osmolality was paralleled by an increase in urine production during the time period 01.00-04.00 (83 +/- 24 vs 52 +/- 18 and 45 +/- 22 ml, respectively, p < 0.05). At the end of the 6-month period of DDAVP treatment, the percentage response was similar between the ADH- and ADH+ enuretics (79% vs 75%). However, the time taken to achieve a response was quicker in the ADH- subjects. These data suggest the existence of a subgroup of enuretics whose underlying pathophysiology is the development of nocturnal polyuria probably due to a relative night-time ADH deficiency. Nocturnal sequential monitoring of urinary osmolality, as described above, allows identification of this subgroup.     

Do pad tests and voiding diaries affect patient willingness to participate in studies of incontinence treatment outcomes?

PURPOSE: We used the Simplified Urinary Incontinence Outcome Score (SUIOS) to retrospectively assess the continence outcomes following 107 consecutive autologous rectus fascia pubovaginal sling procedures. This outcome score requires completion of a questionnaire, voiding diary and pad test. The voiding diary and pad test provide objective data but require a degree of patient effort and motivation. We determine if the voiding diary and pad test requirements would significantly reduce the rate of followup. MATERIALS AND METHODS: After recruitment letters were mailed to all eligible patients, followup telephone calls were made to ask them to complete the SUIOS protocol. Those who agreed were mailed a packet containing the pre-weighed pads, voiding diary and questionnaire. Patients who refused were asked to complete a telephone questionnaire instead. Patients were given 1 month to complete and return the study materials. If the materials were not returned, repeat telephone reminders were made. If patients were unwilling to complete the protocol at this point, they were offered the option of completing only the questionnaire by telephone. Treatment outcomes were classified according to the SUIOS protocol, and the followup rate for the full protocol was compared with that for the questionnaire only responses. RESULTS: Of the 107 patients 18 were lost to followup and 10 refused to participate, leaving 79 (74%) evaluable patients. Mean followup interval was 31 months (range 9 to 66). Of the 79 women 38 (48%) completed the questionnaire portion but were unwilling to complete the voiding diary and pad test. The remaining 41 patients (52%) completed the entire protocol. Complete SUIOS scores were 59% cured, 24% good response, 10% fair response, 2% poor response and 5% failure. Questionnaire response results were similar, with 61% cured, 32% improved and 8% failed. CONCLUSIONS: The majority of our patients were unwilling to complete a pad test and voiding diary for the purpose of assessing outcomes after anti-incontinence surgery. The possible increased accuracy of these outcome measures needs to be weighed against the lower followup rate associated with their use.     

Should measurement of maximum urinary flow rate and residual urine volume be a part of a "minimal care" assessment programme in female incontinence?

OBJECTIVE: The aim of this study was to evaluate the value of routine measurements of urinary flow rate and residual urine volume as a part of a "minimal care" assessment programme for women with urinary incontinence in detecting clinical significant bladder emptying problems. MATERIAL AND METHODS: Four hundred and eight women were examined and treated in an open-access, interdisciplinary incontinence clinic. A standardized programme for investigation and primarily non-surgical treatment of incontinence was applied. RESULTS: Of the 408 women 43% reported subjectively incomplete bladder emptying. Twenty-six per cent had a maximum flow rate less than 15 ml/s, but only 4% at a voided volume > or =200 ml. Residual urine more than 149 ml was found in 6%. Two women had chronic retention with overflow incontinence. Both had typical symptoms with continuous leakage, stranguria and chronic cystitis. Another woman had an urethral stricture with massive bladder emptying symptoms. In the remaining 172 women with symptoms suggesting bladder emptying problems, all but 3 were managed by triple voiding and timed micturition. In these 3 patients, who also had chronic cystitis, the treatment was supplemented with clean intermittent self-catheterization. CONCLUSION: The few women (6 (1.5%)) in whom measurements of urinary flow rate and residual urine volume had a clinical therapeutic consequence, cannot justify these measurements to be routine in a "minimal care" programme for assessment of primary, uncomplicated female urinary incontinence. Thus, primary health care providers can assess women based on simple guidelines without expensive equipment for assessment of urine flow rate and residual urine.     

Does developmental dysplasia of the hip cause a delay in walking?

Developmental dysplasia of the hip (DDH) is commonly supposed to lead to a delay in walking. The authors present a retrospective review of the age of walking in 86 children with established DDH and compare them with an age- and sex-matched group of controls. While the median age of walking was 1 month later than in the control group, this was clinically insignificant, as all walked within the normal time limits. The authors conclude that children with DDH do not present as late walkers.     

Does a longer delay in fixation of talus fractures cause osteonecrosis?

This retrospective study investigated active duty soldiers with delayed definitive fixation of combat-related talus fractures. The authors predicted a longer delay to internal fixation and a correlation between the timing of fixation and development of osteonecrosis and posttraumatic arthritis. The Joint Theater Trauma Registry was queried by ICD-9 codes for talus fractures. Soldiers, ages 18 to 40, with talus fracture between 2001 and 2008 were included. Radiographs identified the injury type, Hawkins sign, osteonecrosis, and posttraumatic arthritis. Mean time to fixation was 12.9 days. Hawkins sign was observed in 59% of fractures at a mean of 7 weeks. No correlation was found between osteonecrosis or posttraumatic arthritis and open fractures, comminuted fractures, or timing of fixation. Average follow-up was 16 months. This case series has the longest mean time to fixation by more than threefold. There was no correlation of delayed timing of fixation and development of osteonecrosis or posttraumatic arthritis.     

Are there concepts in treatment of metacarpale fractures? Own results and a review of the literature of last 12 years

As the treatment of metacarpal fractures is today still a controversial subject, we conducted an analysis of the literature in order to present the different therapy guidelines, indications, and their results. The data from the follow-up of 1602 patients was taken from literature which dated from 1 January 1984 to 31 March 1996. A total of 522 patients who underwent surgery received K-wires, screws or external minifixateur. The conservative approaches ranged from immobilization to various methods of mobilization with different aids or without fixation of the fracture. The mobilization in a brace provided good to excellent results in 95% of the cases; however, the failure rate of therapy was 23% because of local bruises and skin necrosis (3%). The mobilization with handcast, tape etc. attained good to excellent results in 94% of the cases. Here, no complications occurred. Both the immobilization treatment and the surgery provided good to excellent results in 85% of the cases. The reposition of fractures of the fifth metacarpal was successful in only 15% of the cases. Fractures with dislocations below 30 degrees, a shortening of less than 5 mm, no rotational displacement or that below 10 degrees, no articular incongruency, and no relevant soft tissue trauma do not need surgery according to our results and should be treated with early mobilization as suggested by the survey. Beyond these limits a primary surgical therapy is justified. The immobilization of metacarpal fractures over a period of more than 3-4 weeks is not necessary.     

Are leukocytes in salvaged washed autologous blood harmful for the recipient? The results of a pilot study

To explore whether polymorphonuclear leukocytes (PMNL) are activated to the priming threshold through intraoperative blood salvage, and are thus able to induce endothelial damage, we investigated chemotactic response (n = 20) and respiratory burst (RB; n = 20) of PMNL without (basal respiratory burst, bPMNL-RB) and after in vitro stimulation with formyl-Met-Leu-Phe (fMLP-RB) and phorbol myristate acetate (PMA-RB). Blood was processed with a continuous autotransfusion device (CATS). Heparin (Heparin group) and sodium citrate (Citrate group) were used alternately as an anticoagulant for each half of the chemotaxis and RB studies. Comparison of measurements from the processed autologous erythrocyte concentrates (paEC) to pre- and intraoperative arterial blood samples showed no statistically significant difference for any test of PMNL functional responses in an orthopedic patient population. Analysis of intraindividual changes demonstrated a significantly increased bPMNL-RB (both groups, P = 0.0032; Heparin group, P = 0.0098), fMLP-RB (both groups, P = 0.0484; Citrate group, P = 0.0371), and PMA-RB (Citrate group, P = 0.002) in the paEC compared with intraoperative arterial samples, whereas the chemotactic response did not change. Nevertheless, median values of all RB measurements in the paEC were within the range of pre- and intraoperative values, indicating that PMNLs contained in the paEC are neither impaired nor activated to the priming threshold. The results confirm the clinical experience that intraoperative blood salvage is safe to use during major orthopedic surgery and questions the beneficial effect of special leukocyte-removing filters.     

Are black and Hispanic persons disproportionately affected by COVID-19 because of higher obesity rates?

BackgroundOn March 13, 2020, the World Health Organization declared COVID-19 a pandemic. Shortly after that, it was reported that mortality rates in New York City (NYC), the epicenter of the pandemic in the United States, were found to be significantly higher in black and Hispanic populations.ObjectivesThe aim of this article is to evaluate the mortality rates in NYC among the different ethnic groups and the different boroughs as they relate to the obesity rates to see whether this issue merits further evaluation.SettingNYC.MethodsCOVID-19 data were obtained from the official New York authorities in relation to total number of cases in the different boroughs of NYC. Age-adjusted COVID-19–related mortality rates of the different ethnic groups were also obtained. These data were cross-compared with historic community health data on obesity rates previously published and also obesity rates among the different ethnic groups in NYC.ResultsThe 2 NYC boroughs that have the highest mortality rates are the Bronx (6%) and Brooklyn (5.4%). Both the Bronx and Brooklyn were also found to have the highest obesity rates at 32% and 27%, respectively. The 2 ethnic groups with the highest obesity rates (Hispanic and black) were also found to have the highest age-adjusted mortality rates per 100,000 compared with the other ethnic groups (22.8% and 19.8%, respectively).ConclusionsThe Hispanic and black populations in NYC seem to be disproportionately affected by the COVID-19 pandemic because of the higher incidence of mortality rates. Obesity may have played a role in the high incidence of mortality in those ethnic groups.     

Clopidogrel: is a surgical delay necessary in fractured neck of femur?

INTRODUCTION

This paper assesses the outcomes of patients after surgery for a proximal femur fracture while on clopidogrel. It describes a single-centre retrospective observational study over a two-year period.

PATIENTS AND METHODS

A total of 31 surgical patients were included in this study. Of these, 28 were on clopidogrel and 3 on dipyridamole. Patients were split into subgroups based on when surgery took place and the type of hip fracture. The ‘early surgery’ (<48 hours from admission to theatre) group contained 16 patients (51.6%) and the ‘late surgery’ (>48 hours) group composed 15 patients (48.4%). Type of surgery performed and pre-and postoperative haemoglobin (Hb) levels were recorded. Furthermore, the number of units of blood transfused per patient as well as complications before and after surgery were noted.

RESULTS

A significantly larger mean Hb drop occurred in the early surgery group (3.2g/dl) compared with the late surgery group (2.3g/dl) (p=0.027). The mean length of inpatient stay was 21 days in the early and 23 days in the late group (p=0.456). A significantly larger Hb mean drop occurred in patients with extracapsular hip fractures (3.4g/dl; n=16) compared with patients with intracapsular fractures (2.3g/dl; n=15) (p=0.020). The extracapsular patients had longer stays in hospital: 24.5 days versus 19.8 days in the intracapsular group (p=0.521). There was no statistical difference in the 30-day mortality between the early surgery (3/16 deaths) and late surgery (2/15 deaths) groups (p=0.481).

CONCLUSIONS

Patients with extracapsular fractures, treated with early surgery, appear to be most at risk of complications after surgery.