Continuous passive motion for preventing venous thromboembolism after total knee arthroplasty

Continuous passive motion not affect the knee motion and the surgical wound aspect after total knee arthroplasty

Background

This study aimed to assess whether use of continuous passive motion (CPM) could improve range of motion in patients after total knee arthroplasty (TKA), if it could affect the surgical wound aspect (SWA) and if it could influence on pain management after TKA.

Methods

We randomized 210 patients in two groups, 102 patients in the CPM group, who received a standard rehabilitation protocol together with CPM application; and 108 patients in the no-CPM group, without CPM. Variables as knee motion (flexion, extension, range of motion) and pain were measured before surgery, on the 1st, 2nd and 3rd postoperative day, and in the 2nd, 6th, 12th and 24th postoperative weeks following TKA. The SWA was determined by the “surgical wound aspect score” (SWAS) in the next 48 h after surgery. This scale analyzes swelling, erythema, hematoma, blood drainage and blisters.

Results

There was an improvement in the knee motion over the course of follow-up in both groups, without significant difference in flexion parameter. We found no significant differences in the total score of SWA, except for hematoma, with less severity in the CPM group. Furthermore, we found no differences in the others SWAS parameters and pain.

Conclusions

The application of CPM does not provide benefit to our patients undergoing TKA in terms of either improved flexion mobility or decreased pain. No relationship was found between the use of CPM and the global score of SWA following a TKA, except for a decrease in hematoma appearance.

Common controversies in total knee replacement surgery: Current evidence

Total knee replacement (TKR) is a widely used operation that has radically improved the quality of life of millions of people during the last few decades. However, some technical details, concerning the surgical procedure and the rehabilitation following total knee arthroplasty, are still a matter of a strong debate. In this review of the literature, we have included the best evidence available of the last decade, in an effort to shed light on some of the most controversial subjects related to TKR surgery. Posterior-stabilized or cruciate-retaining prosthesis? To use a tourniquet during operation or not? Do patients need continuous passive motion for their post-surgery rehabilitation? To resurface patella or not? These are some of the most controversial topics that until now have been persistent dilemmas for the orthopedic surgeon. Results of this systematic review of the literature are highly controversial. These conflicting results are an indication that larger and more well conducted high quality trials are needed in order to gain more secure answers. At the same time, it is becoming apparent that a meticulous operative technique, respecting the soft tissue envelope and knowing the principles of alignment and soft tissue balancing, are some of the parameters that might contribute more to achieving the optimal results for the patients.

Continuous passive motion for preventing venous thromboembolism after total knee arthroplasty

BACKGROUND

Total knee arthroplasty (TKA) is a common form of orthopaedic surgery. Venous thromboembolism (VTE), which consists of deep venous thrombosis (DVT) and pulmonary embolism (PE), is a major and potentially fatal complication after TKA. The incidence of DVT after TKA is 40% to 80% and the incidence of PE is approximately 2%. It is generally agreed that thromboprophylaxis should be used in patients who undergo TKA. Both pharmacological and mechanical methods are used in the prevention of DVT. Pharmacological methods alter the blood coagulation profile and may increase the risk of bleeding complications. When pharmacological methods cannot be used the mechanical methods become crucial for VTE prophylaxis. Continuous passive motion (CPM) is provided through an external motorised device which enables a joint to move passively throughout a preset arc of motion. Despite the theoretical effectiveness and widespread use of CPM, there are still differing views on the effectiveness of CPM as prophylaxis against thrombosis after TKA. This is an update of the review first published in 2012.

OBJECTIVES

The aim of this review was to determine the effectiveness of continuous passive motion (CPM) therapy for preventing venous thromboembolism (VTE) in patients after total knee arthroplasty (TKA).

SEARCH METHODS

For this update the Cochrane Peripheral Vascular Diseases Group Trials Search Co-ordinator searched the Specialised Register (last searched February 2014), CENTRAL (2014, Issue 1), Ovid MEDLINE (to week 1 February 2014) and EMBASE (to Week 07 2014).

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing the use of CPM with control in preventing DVT or PE after TKA. People aged 18 years and older who had undergone TKA were included in this review. We excluded studies of patients who presented with DVT at baseline. The experimental and control groups received similar postoperative care and therapy other than the CPM.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed the citations retrieved by the search strategies for reports of relevant RCTs. They independently selected trials that satisfied the inclusion criteria, extracted data and undertook quality assessment. Effects were estimated as risk ratios (RRs), mean differences or standardised mean differences with 95% confidence intervals (CIs). Meta-analyses were performed using a fixed-effect model for continuous variables. Where heterogeneity existed (determined by the I(2) statistic) a random-effects model was used.

MAIN RESULTS

Eleven RCTs involving 808 participants met the inclusion criteria. The methodological quality of the included studies was variable and most of the predefined outcomes were reported by only one or two studies, therefore the quality of the evidence was low. Five studies with a total of 405 patients reported the incidence of DVT. In the CPM group (205 patients) 36 developed DVT (18%) compared to 29 (15%) in the control group (200 patients). The results of the meta-analysis showed no evidence that CPM had any effect on preventing VTE after TKA (RR 1.22, 95% CI 0.84 to 1.79). One trial (150 participants) did not find PE in any of the patients during hospitalisation or in the subsequent three months. PE was not reported in the other included studies. None of the trials reported deaths among the included participants.

AUTHORS' CONCLUSIONS

There is not enough evidence from the available RCTs to conclude that CPM reduces VTE after TKA. We cannot assess the effect of CPM on mortality because no such events occurred amongst the participants of these trials. The quality of the evidence was low. The results are supported by only a small number of studies, most of which are of low to moderate quality.