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The Bone & Joint Journal
Vol. 106-B, Issue 3 Supple A | Pages 115 - 120
1 Mar 2024
Ricotti RG Flevas DA Sokrab R Vigdorchik JM Mayman DJ Jerabek SA Sculco TP Sculco PK

Aims

Periprosthetic femoral fracture (PPF) is a major complication following total hip arthroplasty (THA). Uncemented femoral components are widely preferred in primary THA, but are associated with higher PPF risk than cemented components. Collared components have reduced PPF rates following uncemented primary THA compared to collarless components, while maintaining similar prosthetic designs. The purpose of this study was to analyze PPF rate between collarless and collared component designs in a consecutive cohort of posterior approach THAs performed by two high-volume surgeons.

Methods

This retrospective series included 1,888 uncemented primary THAs using the posterior approach performed by two surgeons (PKS, JMV) from January 2016 to December 2022. Both surgeons switched from collarless to collared components in mid-2020, which was the only change in surgical practice. Data related to component design, PPF rate, and requirement for revision surgery were collected. A total of 1,123 patients (59.5%) received a collarless femoral component and 765 (40.5%) received a collared component. PPFs were identified using medical records and radiological imaging. Fracture rates between collared and collarless components were analyzed. Power analysis confirmed 80% power of the sample to detect a significant difference in PPF rates, and a Fisher’s exact test was performed to determine an association between collared and collarless component use on PPF rates.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_12 | Pages 15 - 15
23 Jun 2023
Ricotti RG Flevas D Sokrab R Vigdorchik JM Sculco TP Sculco PK
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Periprosthetic femur fracture (PFF) is a major complication following total hip arthroplasty (THA) that carries significant morbidity, mortality, and economic burden. Currently, uncemented stems are highly preferred in primary THA, but have been associated with higher risk of PFF compared to cemented stems. The use of collared stems in uncemented primary THA has shown promise in reducing PFF rates postoperatively.

This retrospective study included 2,294 uncemented primary THAs using the posterior approach performed by two attending surgeons from January 2016 to December 2022. Both surgeons switched from a collarless femoral stem design to a collared design in May 2020. Data was collected regarding stem design, frequency of PFF, and requirement for revision surgery. Periprosthetic fractures were identified and confirmed using medical records and/or radiographic imaging. Fracture rates and percentages between collared and collarless stems were then analyzed. A Fisher's Exact Test was performed to determine if there was a significant association between collared and collarless stem use on PFF rates.

A total of 2,294 uncemented primary THAs performed by 2 surgeons were eligible for analysis. 903 (39.4%) patients received a collared stem, and 1,391 (60.6%) patients received a collarless stem. In total, 14 (0.6%) PFFs occurred over the study period. There was 1 fracture (0.1%) out of 903 collared stems, and 13 fractures (0.9%) out of 1,391 collarless stems (p = 0.012).

Collared stems were associated with a significant decrease in PFF rate when compared to collarless stems in uncemented primary THA. Future studies are encouraged to continue to investigate PFF and other complication rates with the use of a collared stem design.


The Bone & Joint Journal
Vol. 105-B, Issue 3 | Pages 277 - 283
1 Mar 2023
Gausden EB Puri S Chiu Y Figgie MP Sculco TP Westrich G Sculco PK Chalmers BP

Aims

The purpose of this study was to assess mid-term survivorship following primary total knee arthroplasty (TKA) with Optetrak Logic components and identify the most common revision indications at a single institution.

Methods

We identified a retrospective cohort of 7,941 Optetrak primary TKAs performed from January 2010 to December 2018. We reviewed the intraoperative findings of 369 TKAs that required revision TKA from January 2010 to December 2021 and the details of the revision implants used. Kaplan-Meier analysis was used to determine survivorship. Cox regression analysis was used to examine the impact of patient variables and year of implantation on survival time.


The Bone & Joint Journal
Vol. 103-B, Issue 6 Supple A | Pages 108 - 112
1 Jun 2021
Kahlenberg CA Krell EC Sculco TP Katz JN Nguyen JT Figgie MP Sculco PK

Aims

Many patients undergoing total knee arthroplasty (TKA) have severe osteoarthritis (OA) in both knees and may consider either simultaneous or staged bilateral TKA. The implications of simultaneous versus staged bilateral TKA for return to work are not well understood. We hypothesized that employed patients who underwent simultaneous bilateral TKA would have significantly fewer days missed from work compared with the sum of days missed from each operation for patients who underwent staged bilateral TKA.

Methods

The prospective arthroplasty registry at the Hospital for Special Surgery was used. Baseline characteristics and patient-reported outcome scores were evaluated. We used a linear regression model, adjusting for potential confounding variables including age, sex, preoperative BMI, and type of work (sedentary, moderate, high activity, or strenuous), to analyze time lost from work after simultaneous compared with staged bilateral TKA.


Orthopaedic Proceedings
Vol. 102-B, Issue SUPP_9 | Pages 76 - 76
1 Oct 2020
Kahlenberg CA Krell E Sculco TP Figgie MP Sculco PK
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Introduction

A large proportion of patients undergoing total knee arthroplasty (TKA) have severe osteoarthritis in both knees and may consider either simultaneous or staged bilateral TKA. The implications of staged versus simultaneously bilateral TKA for return to work are not well understood. We hypothesized that employed patients who underwent simultaneous bilateral TKA would have significantly fewer days missed from work compared to the sum of days missed from each surgery for patients who underwent staged bilateral TKA.

Methods

The prospective arthroplasty registry at Hospital for Special Surgery was utilized. We identified 61 employed patients who had undergone staged bilateral TKA and 152 employed patients who had undergone simultaneous bilateral TKA and had completed the registry's return to work questionnaire. Baseline characteristics and patient reported outcome scores were evaluated. We used a linear regression model, adjusting for potential confounders including age, sex, pre-op BMI, and work type (sedentary, moderate, high activity, or strenuous), to analyze workdays lost after staged versus simultaneous bilateral TKA.


The Bone & Joint Journal
Vol. 102-B, Issue 4 | Pages 485 - 494
1 Apr 2020
Gu A Malahias M Selemon NA Wei C Gerhard EF Cohen JS Fassihi SC Stake S Bernstein SL Chen AZ Sculco TP Cross MB Liu J Ast MP Sculco PK

Aims

The aim of this study was to determine the impact of the severity of anaemia on postoperative complications following total hip arthroplasty (THA) and total knee arthroplasty (TKA).

Methods

A retrospective cohort study was conducted using the American College of Surgeons National Quality Improvement Program (ACS-NSQIP) database. All patients who underwent primary TKA or THA between January 2012 and December 2017 were identified and stratified based upon hematocrit level. In this analysis, we defined anaemia as packed cell volume (Hct) < 36% for women and < 39% for men, and further stratified anaemia as mild anaemia (Hct 33% to 36% for women, Hct 33% to 39% for men), and moderate to severe (Hct < 33% for both men and women). Univariate and multivariate analyses were used to evaluate the incidence of multiple adverse events within 30 days of arthroplasty.


Orthopaedic Proceedings
Vol. 101-B, Issue SUPP_12 | Pages 5 - 5
1 Oct 2019
Sculco PK Nocon AA Selemon NA Diane A Demartino AM Mayman DJ Sculco TP
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Introduction

The anatomic dual mobility (ADM) technology utilized a monoblock cobalt chromium acetabular component. However, design limitations conferred difficulties controlling orientation during component insertion and inability to confirm full implant seating; the solution resulted in the creation of the modular dual mobility (MDM). The modular implant combines a standard titanium acetabular component and a cobalt chromium liner insert. Due to the metal-on-metal interface on MDM implants, fretting and corrosion releasing metal ions like previous metal-on-metal THA implants, were a concern. This study prospectively reviewed metal ions (cobalt, chromium and titanium) on patients who were at least 1 year post MDM implantation and compared them to patients with an ADM implant and evaluated radiographic seating of the components.

Methods

All patients with ADM and MDM implants underwent evaluation of metal ions (cobalt, chromium and titanium) at their one year follow-up appointment. Radiographic evaluation for acetabular polar gaps was performed. Elevated metal ions were determined using standard laboratory ranges. Differences in baseline demographics were assessed using the Mann Whitney-U test and Fishers's exact test. Differences in metal ions and implant type were compared using the Fisher's exact tests.


The Bone & Joint Journal
Vol. 101-B, Issue 1_Supple_A | Pages 41 - 45
1 Jan 2019
Jones CW De Martino I D’Apolito R Nocon AA Sculco PK Sculco TP

Aims

Instability continues to be a troublesome complication after total hip arthroplasty (THA). Patient-related risk factors associated with a higher dislocation risk include the preoperative diagnosis, an age of 75 years or older, high body mass index (BMI), a history of alcohol abuse, and neurodegenerative diseases. The goal of this study was to assess the dislocation rate, radiographic outcomes, and complications of patients stratified as high-risk for dislocation who received a dual mobility (DM) bearing in a primary THA at a minimum follow-up of two years.

Materials and Methods

We performed a retrospective review of a consecutive series of DM THA performed between 2010 and 2014 at our institution (Hospital for Special Surgery, New York, New York) by a single, high-volume orthopaedic surgeon employing a single prosthesis design (Anatomic Dual Mobility (ADM) Stryker, Mahwah, New Jersey). Patient medical records and radiographs were reviewed to confirm the type of implant used, to identify any preoperative risk factors for dislocation, and any complications. Radiographic analysis was performed to assess for signs of osteolysis or remodelling of the acetabulum.


Orthopaedic Proceedings
Vol. 100-B, Issue SUPP_12 | Pages 16 - 16
1 Oct 2018
Sculco TP Jones C Selemon N Miller A Henry M Sculco PK Nocon AA
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Introduction

Periprosthetic joinTt infection (PJI) remains an uncommon, yet devastating complication of total hip arthroplasty (THA) and total knee arthroplasty (TKA). Debridement with antibiotics and implant retention (DAIR) provides an alternative to staged revision. Chronic infection is considered to be a contraindication to DAIR, however, outcomes stratified by chronicity have not been documented.

Methods

We performed a retrospective review of all DAIR cases performed at our institution between 2008–2015. Timeframe to treatment was categorized as acute (< 6 weeks since surgery), chronic (>6 weeks since surgery) or acute hematogenous (previously well-functioning prosthesis). Treatment failure was defined as reoperation during the first 90-days following DAIR. Univariate analysis (Mann-Whitney U and Chi-square; p<0.05) and generalized estimating equations (GEE) were used with multiple comparison adjustment by Tukey-Kramer method (α = 0.05).


Orthopaedic Proceedings
Vol. 100-B, Issue SUPP_13 | Pages 34 - 34
1 Oct 2018
Sculco TP Goodman SB Nocon AA Sculco PK
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Introduction

Patients with rheumatoid arthritis (RA) have a higher risk of surgical site infection (PJI) than patients with osteoarthritis (OA). Disease modifying therapy is in widespread use in RA patients, and biologic medications may increase Staphylococcus aureus colonization rates. Because S. aureus colonization likely increases risk of surgical infection, perioperative assessments and therapies to decrease the risk of invasive S.aureus infections may be warranted. The objective of this study was to determine if there was a difference in S. aureus carriage among patients with RA, OA, and RA on biologics (RA+B).

Methods

An a priori power analysis determined 123 participants per group were needed to detect a relative difference of 20% among groups with 80% power. After IRB approval, patients were screened; included patients met American College of Rheumatology classification criteria. Patients were approached between April 2017 and May 2018 and asked to perform a nasal swab while on site using the Center for Disease Control's swabbing protocol; questionnaires pertaining to their current health status were collected. Swabs were inoculated onto ChromAgar/ChromID MRSA plates for detection of S. aureus. Mann-Whitney U and Chi-square tests were used to evaluate baseline differences between groups. Logistic regression evaluated the associations between groups and S. aureus carriage. All statistical analyses were performed using SAS Software version 9.3 (SAS Institute, Cary, NC); statistical significance was defined as p<0.05.


Orthopaedic Proceedings
Vol. 100-B, Issue SUPP_12 | Pages 59 - 59
1 Oct 2018
Figgie MP Blevins JL Richardson SS Gausden EB Sculco TP Sculco PK
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Introduction

Total knee arthroplasty (TKA) is a successful treatment for degenerative end stage knee arthritis. Younger patients who undergo TKA may face multiple revisions during their lifetime due to aseptic loosening, infection, and instability. The purpose of this study was to compare the early complication rates and revision free survivorship between age groups undergoing TKA in a nationwide database.

Methods

The PearlDiver national insurance database was queried from 2007–2015 for all patients who underwent primary TKA. Kaplan-Meier Curve survival analysis and log rank test were performed to evaluate revision rates between age groups (<40, 40–49, 50–59, 60–69, 70–79, 80–89, and ≥90 years). Complication rates were compared to rates in the age 60–79 group using multiple logistic regressions controlling for baseline demographics and comorbidities.


Orthopaedic Proceedings
Vol. 100-B, Issue SUPP_1 | Pages 12 - 12
1 Jan 2018
De Martino I D'Apolito R Nocon A Sculco P Sculco TP Bostrom M
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Proximal femoral replacements are commonly used in oncologic limb salvage procedures. Recently, these megaprostheses have been utilized in complex revision arthroplasties where proximal femoral bone is compromised. The purpose of this study is to evaluate the clinical and radiographic survivorship of proximal femoral replacements as a salvage treatment for bone loss after hip arthroplasty. We retrospectively reviewed the clinical and radiographic outcomes of 31 proximal femoral replacements of a single design between 2004 and 2013 at a single institution. The mean age at time of index surgery was 62 years, 58% were female, and mean BMI was 28.1 Kg/m2. The indications and complications associated with megaprosthesis implantation were collected. Average follow-up was 60 months (range 24–120 months). Kaplan-Meier survivorship assessed clinical and radiographic survivorship. Indication for revision, use of a constrained liner and construct length were assessed as risk factors for construct failure.

The indications for proximal femoral replacement were periprosthetic infection (n=12, 38.7%), aseptic loosening (n=10, 32.3%), periprosthetic fracture (n=6, 19.3%), and non-union (n=3, 9.7%). A constrained liner was used in 22 hips (71%). The average length of bone resection was 148 cm (range 81–240 cm). There were nine revisions (29.2%): 3 for infection (9.7%) 2 for dislocation (6.5%), 2 for aseptic loosening (6.5%), and 2 for periprosthetic fracture (6.5%). Two of the 3 infections were in patients treated for infection. Overall survivorship was at 70.8%. There was no relation between the length of the bone resection, indication for revision and failure rate.

Proximal femoral replacement in non-oncologic revision hip arthroplasty demonstrated a high failure rate at 2–10 year follow-up. Despite the high failure rate, the benefits of this salvage construct are that they allow full weight-bearing and allow rapid mobilization with minimal morbidity.


The Bone & Joint Journal
Vol. 99-B, Issue 1_Supple_A | Pages 18 - 24
1 Jan 2017
De Martino I D’Apolito R Soranoglou VG Poultsides LA Sculco PK Sculco TP

Aims

The aim of this systematic review was to report the rate of dislocation following the use of dual mobility (DM) acetabular components in primary and revision total hip arthroplasty (THA).

Materials and Methods

A systematic review of the literature according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines was performed. A comprehensive search of Pubmed/Medline, Cochrane Library and Embase (Scopus) was conducted for English articles between January 1974 and March 2016 using various combinations of the keywords “dual mobility”, “dual-mobility”, “tripolar”, “double-mobility”, “double mobility”, “hip”, “cup”, “socket”. The following data were extracted by two investigators independently: demographics, whether the operation was a primary or revision THA, length of follow-up, the design of the components, diameter of the femoral head, and type of fixation of the acetabular component.


The Journal of Bone & Joint Surgery British Volume
Vol. 94-B, Issue 11_Supple_A | Pages 93 - 94
1 Nov 2012
Sculco TP Sculco PK

In this paper, we will consider the current role of simultaneous-bilateral TKA. Based on available evidence, it is our opinion that bilateral one stage TKR is a safe and efficacious treatment for patients with severe bilateral arthritic knee disease but should be reserved for selected patients without significant medical comorbidities.


Orthopaedic Proceedings
Vol. 92-B, Issue SUPP_I | Pages 11 - 12
1 Mar 2010
Sculco TP Memtsoudis SG Valle AGD Besculides MC Gaber L
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Purpose: To determine mortality and morbidity for bilateral total knee replacment compared to unilateral knee replacement and revision total knee replacement using the National National Hospital Discharge Survey to include large numbers of patients and look at outcomes.

Method: We analyzed nationally representative data to elucidate the demographics, comorbidities, hospital stay, in-hospital complications and mortality of patients undergoing BTKA and compared them with those of patients undergoing UTKA and revision TKA (RTKA). Data in the National Hospital Discharge Survey on hospital discharges with procedure codes for BTKA, UTKA and RTKA between 1990 and 2004 was analyzed. The demographics, comorbidities, in-hospital stay, complications and mortality were studied. We identified 4,169,489 discharges (153,259 BTKAs; 3,677,161 UTKAs; and 339,069 RTKAs).

Results: Patients undergoing BTKA were younger (1.5 years) and had a lower prevalence of comorbidities for hypertension (vs. UTKA), diabetes, lung disease, and coronary artery disease (vs. UTKA and RTKA). The length of hospitalization was 5.8 days for BTKA, 5.28 for UTKA, and 5.41 for RTKA. Despite similar length of hospitalization, the prevalence of procedure related complications was higher for BTKA (14.17%+/−0.76 (SE)) than for UTKA (9.01%+/−0.17) and RTKA (9.84%+/−0.57). In hospital mortality was highest for BTKA patients (BTKA: 0.47%+/−0.15%; UTKA: 0.30%+/−0.03; RTKA: 0.27%+/−0.09).

Conclusion: Despite younger age and lower comorbidity burden, patients undergoing BTKA had an approximately 1.6 times higher rate of procedure related complications and mortality compared to those undergoing UTKA. Outcomes for RTKA patients for most variables were similar to those for UTKA. In a multivariate analysis, BTKA, advanced age and male gender were independent risk factors for complications and mortality following TKA surgery.


Orthopaedic Proceedings
Vol. 90-B, Issue SUPP_I | Pages 165 - 165
1 Mar 2008
Della Valle AG Rana A Furman B Sculco TP Salvati EA
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Backside wear is generated at the non-articulating surfaces of modular acetabular cups. We compared the backside wear of retrieved liners from cementless non-modular and modular cups of first and second generation designs. We match paired for time in situ, patient age and weight, 9 retrieved Harris Galante type 1 liners, 9 Harris Galante type 2, 9 Trilogy, and 9 liners from a modern two-piece preassembled cup (Implex). The average time in situ was 2.5 years (1 to 7). The backside was divided in quadrants and each one examined under a 10x binocular loupe and rated with a score from 0 (absence of wear) to 3 (severe backside wear) for a total ranging from 0 to 12. Among 36 quadrants in the HG1 group there were 3 rated 1, 23 rated 2, and 10 rated 3. In the HG2 group, there was 1 quadrant rated 0, 16 rated 1, 14 rated 2, and 5 rated 3. In the Trilogy group, there were 6 quadrants rated 0, 27 rated 1, and 3 rated 2. In the Implex group, there were 15 quadrants rated 0, 21 rated 1. The average total backside wear score was 8.4; 7.3; 3.7; and 2.3 respectively. The HG cups demonstrated more severe backside wear than the Trilogy and Implex (HG1 vs Trilogy and HG1 vs Implex: p< 0.001; HG2 vs Trilogy and HG2 vs Implex: p< 0.02). There was a tendency towards less backside wear in the Implex cup when compared to the Trilogy (p=0.04). The difference between the HG1 and HG2 was not significant. Despite the limitations imposed by the small sample studied, the presence of multiple screw holes in the Harris-Galante retrievals, and sub-optimal matching for sex, height, and varied indication for revision, we detected significant reduction in the backside wear of modern modular and non-modular acetabular cups when compared to first generation modular designs.


Orthopaedic Proceedings
Vol. 87-B, Issue SUPP_II | Pages 172 - 172
1 Apr 2005
Baldini A Sculco TP
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The use of stems with constrained condylar knee (CCK) prosthesis components has been advocated both for primary and revision total knee arthroplasty (TKA). CCK “nonmodular” implants without diaphyseal stems reduce the invasion of the medullary canal, thereby reducing operative time and costs; render a subsequent revision procedure easier, and avoid possible stem pain. The present study is the first report on mid-term results of stemless CCK for primary TKA.

This cross-sectional study reviewed the outcome for 248 knees (180 patients) in which primary TKA was performed using the Exactech nonmodular CCK between 1997 and 2001. The patients had an average age of 68 years and the preoperative diagnosis was osteoarthritis in 94%. Preoperative deformity was severe (82% Ahlback grade 4–5). Valgus deformity was present in 59% and averaged 15° (7–33°). Varus deformity, present in 41% of the patients, averaged 13° (5–22°). Fifty-seven percent of the patients had multiple joint involvement (category C).

Clinical and radiological follow-up at an average of 47 months (range, 24–72 months) was obtained for 192 TKAs (148 patients). Of the total group, there were 15 deaths and 17 patients were lost to follow-up. The Knee Society score improved from 36 to 89 and the functional score from 42 to 76 postoperatively. Varus-valgus laxity improved from 11° (range: 0–30°) to 2° (range:0–6°). Nonprogressive radiolucent lines were present in 16%. Failure rate, defined as revision, was 3% (two infections, two aseptic loosenings, one broken post, and one supra-condylar femoral fracture). In six knees (3%) patello-femoral complications developed: five patellar clunks and one dislocation.

Use of a stemless “nonmodular” CCK for primary severely damaged knees demonstrated reliable mid-term results with a low complication rate.


The Journal of Bone & Joint Surgery British Volume
Vol. 83-B, Issue 5 | Pages 676 - 679
1 Jul 2001
Bae H Westrich GH Sculco TP Salvati EA Reich LM

We have assessed the effect of the donation of autologous blood and the preoperative level of haemoglobin on the prevalence of postoperative thromboembolism in 2043 patients who had a total hip arthroplasty. The level of haemoglobin was determined seven to ten days before surgery and all patients had venography of the operated leg on the fifth postoperative day. The number of patients who had donated autologous blood (1037) was similar to that who had not (1006).

A significant decrease in the incidence of deep-vein thrombosis (DVT) was noted in those who had donated blood preoperatively (9.0%) compared with those who had not (13.5%) (p = 0.003). For all patients, the lower the preoperative level of haemoglobin the less likely it was that a postoperative DVT would develop.

Of those who had donated blood, 0.3% developed a postoperative pulmonary embolism compared with 0.7% in those who had not, but this difference was not statistically significant. No significant difference was found in the requirements for transfusion between the two groups.


The Journal of Bone & Joint Surgery British Volume
Vol. 80-B, Issue 6 | Pages 1057 - 1066
1 Nov 1998
Westrich GH Specht LM Sharrock NE Windsor RE Sculco TP Haas SB Trombley JF Peterson M

We performed a crossover study to evaluate the haemodynamic effect of active dorsal to plantar flexion and seven pneumatic compression devices in ten patients who had a total knee arthroplasty. Using the Acuson 128XP/10 duplex ultrasound unit with a 5MHz linear array probe, we assessed the augmentation of peak venous velocity and venous volume above and below the junction of the greater saphenous and common femoral veins in order to study both the deep and superficial venous systems.

The pneumatic compression devices evaluated included two foot pumps (A-V Impulse System and PlexiPulse Foot), a foot-calf pump (PlexiPulse Foot-Calf), a calf pump (VenaFlow System) and three calf-thigh pumps (SCD System, Flowtron DVT and Jobst Athrombic Pump). The devices differed in a number of ways, including the length and location of the sleeve and bladder, the frequency and duration of activation, the rate of pressure rise, and the maximum pressure achieved. A randomisation table was used to determine the order of the test conditions for each patient.

The enhancement of peak venous velocity occurred primarily in the deep venous system below the level of the saphenofemoral junction. The increases in peak venous velocity were as follows: active dorsal to plantar flexion 175%; foot pumps, A-V Impulse System 29% and PlexiPulse 65%; foot-calf pump, PlexiPulse, 221%; calf pump, VenaFlow, 302% and calf-thigh pumps, Flowtron DVT 87%, SCD System 116% and Jobst Athrombic Pump 263%.

All the devices augmented venous volume, the greatest effect being seen with those incorporating calf compression. The increases in ml/min were found in the deep venous system as follows: foot pumps, A-V Impulse System 9.6 and PlexiPulse Foot 16.7; foot-calf pump, PlexiPulse, 38.1; calf pump, VenaFlow, 26.2; calf-thigh pumps, Flowtron DVT 61.5, SCD System 34.7 and Jobst Athrombic Pump 82.3. Active dorsal to plantar flexion generated 8.5 ml for a single calf contraction.