Effects of Unilateral Tourniquet Used in Patients Undergoing Simultaneous Bilateral Total Knee Arthroplasty

Abstract

Objective

To assess the benefits of use of a tourniquet in one limb in patients undergoing simultaneous bilateral total knee arthroplasty (TKA).

Methods

A prospective randomized trial was designed to evaluate the outcomes of unilateral tourniquet use during simultaneous bilateral TKA. A total of 52 (36 women and 16 men) patients with osteoarthritis who underwent simultaneous bilateral primary TKA between January 2010 and January 2015 were assigned randomly to tourniquet (TG) or non‐tourniquet (NG) groups prior to surgery. Operating time, pain score, range of motion, first active straight‐leg raise time, swelling, wound healing, deep vein thrombosis, and Knee Society score were observed.

Results

Mean operating time in the TG group was shorter than that in the NG group (P < 0.05). Postoperative pain was measured by a visual analog scale (VAS) and straight‐leg raise time, which was lower and shorter in limbs operated without the use of a tourniquet (P < 0.05). In addition, this group had less postoperative swelling and lower incidence of wound complications in the early postoperative period (P < 0.05). There was no significant difference in the range of motion (ROM), deep venous thrombosis incidence, and Knee Society scores between the two groups.

Conclusions

Tourniquet use in bilateral TKA can reduce intraoperative time but was associated with a higher incidence of wound complications and larger postoperative knee swelling.

Introduction

Total knee arthroplasty (TKA) is a major orthopaedic procedure that is commonly performed in patients with knee joint function that has been severely restricted. TKA could significantly improve the quality of life for these patients by relieving disabling joint pain and restoring mobility. For this reason, the number of TKA has steadily increasing in recent years worldwide. TKA, especially simultaneous bilateral TKA, can cause massive blood loss and increase the incidence of many complications. Therefore, a number of measures have been used in TKA to reduce blood loss, such as tourniquets, hemostatic drugs (e.g. tranexamic acid), and careful operative procedures. The use of a tourniquet during TKA has evolved considerably over the past few decades. Its benefits include improved intraoperative visualization due to the bloodless field, which theoretically provides a better cement–bone interface between the bone surface and prosthesis in cemented TKA, and, thus, reduces the surgical time and intraoperative blood loss1, 2, 3, 4, 5.

Despite the fact that use of an intraoperative tourniquet is widespread among orthropaedic surgeons, tourniquet use in TKA is always a controversial issue. There are many studies that have shown that the use of a tourniquet has not resulted in improved clinical outcomes, especially with respect to range of movement, pain, and established Knee Society score in the long‐term6, 7, 8, 9. Indeed, use of a tourniquet was shown to increase the incidence of venous thromboembolism (VTE) due to venous stasis, direct trauma to the vessel wall, and/or increased platelet adhesion in the valve pockets after distal limb ischemia. Although serious VTE is rare, fatal pulmonary embolism and arterial occlusion have been reported. Other problems also arise with its use, especially neuromuscular injury secondary to the ischemia of neural and muscular tissues, and direct compressive injury to nerves8. Furthermore, it has been shown to cause wound problems, such as ooze and soakage, and to delay recovery of muscle power10, 11. The change in circulatory volume associated with limb exsanguination and the reactive hyperaemia induced by release of the tourniquet can also cause serious circulatory and respiratory complications, particularly in patients with poor cardiac function. The potential severity of these volume changes and the accompanying alterations in acid–base balance is demonstrated by reports of acute pulmonary edema and cardiac arrest immediately after tourniquet release. The relatively higher morbidity and mortality of bilateral procedures may be related to simultaneous release of both tourniquets.

There are variations in the profile of its use. Some surgeons use the tourniquet throughout the procedure, some use it for part of the procedure, and other surgeons use no tourniquet at all. Increasing awareness of the risks associated with the use of tourniquets requires a reevaluation of their potential benefits and complications. Most level I studies have evaluated the use of tourniquets in subjects undergoing unilateral TKA.

It is very difficult to implement a complete control study in different individual cases for evaluating the benefits of tourniquet use during TKA. There is a paucity of adequate evidence to either accept or reject the use of tourniquets in simultaneous bilateral knee arthroplasty. Although bilateral simultaneous TKA is associated with more peri‐operative complications and varied outcomes, the current use of tourniquets in such cases is an extrapolation from unilateral cases, which is a procedure either with or without use of tourniquets in both limbs. We designed a protocol in which a tourniquet was applied only to one limb in patients undergoing simultaneous bilateral TKA, in order to reduce the limb ischemia time and to minimize secondary complications. The objective of this study was to evaluate the effects of the protocol and to compare the outcomes achieved with and without use of a tourniquet in a prospective randomized trial.

Patients and Methods

Inclusion and Exclusion Criteria

Inclusion criteria were bilateral severe osteoarthritis with pain, accompanied with or without significant deformity and failure of conservative treatment. Exclusion criteria were recent or current knee sepsis, extensor mechanism discontinuity or severe dysfunction, age >70 years, coagulation disorder or treatment with drugs known to influence coagulation, diabetes, renal or liver disease, severe cardiovascular problems, lung disease, neurological disorders, or cancer. For elderly patients (age >70 years) with bilateral osteoarthritis, we prefer staged TKA owing to their frailty, compromised cardiopulmonary function, and the increased risk of postoperative complications associated with bilateral simultaneous TKA in these patients, so they are excluded from the current study.

Patients

A total of 56 consecutive patients underwent simultaneous bilateral primary TKA between January 2010 and January 2015. Finally, 52 (36 women and 16 men) patients with osteoarthritis were included in the study.

Using a random number table, the left and right knees of 52 patients were assigned randomly to tourniquet (TG) or non‐tourniquet (NG) groups prior to the surgery. Despite random group allocation, there was unequal distribution in the TG and NG groups owing to the small sample size. Finally, a total of 27 left knees and 25 right knees were included in the TG group, while 25 left and 27 right knees were included in the NG group. TKA for all patients was performed by the same surgical team, using a standard surgical protocol under general anesthesia. Based on randomization, a tourniquet was used during the surgery in 1 knee only. Bilateral simultaneous TKA was carried out and as a matter of habit of the operating surgeon the left knee was operated on first. Right knee surgery was initiated by the operating surgeon while the closure process on the left side was completed by the assisting surgeon.

Surgical Technique and Postoperative Treatment

The tourniquet was applied on a layer of cotton wool padding applied over the thigh. Both right and left thighs were prepared with a tourniquet prior to surgery and only the limb of the TG side was elevated and exsanguinated with a rubber limb Eschmarch's bandage. The tourniquet was then inflated to a pressure of 125‐mm Hg above the systolic blood pressure (SBP) just prior to the incision. Longitudinal incisions were made at the midline with the knee positioned in 90° flexion, from 4‐cm proximal to the upper end of the patella up to the tibial tuberosity. The tourniquet was inflated for less than 120 min, until wound closure was done and compressive dressing was applied. For the NG knees, SBP was maintained at a level of approximately 100 mm Hg at the time of cementation with antihypertensive drugs. The posterior stabilized knee prostheses (26 GENESIS II [Smith & Nephew, Memphis, Tenn, USA]; 26, Vanguard [Biomet, Warsaw, IN, USA]) were used in the surgery. Peri‐articular injection of ropivacaine (200 mg), adrenaline hydrochloride (0.1 mg), and morphine (5 mg) was administered just prior to skin closure. All wounds were closed using staples with a drain. Drains were inserted into the joint and connected to Stryker CBC II (Stryker, Kalamazoo, MI, USA) auto‐transfusion. Allogeneic allograft blood transfusion was performed, when postoperative hemoglobin was less than 8.0 g/L.

Intravenous patient control analgesia (PCA) with morphine was started postoperatively. All patients received rivaroxaban (10 mg, once a day) from the first postoperative day, for 2 weeks, as prophylaxis against thromboembolic complications. Getting out of bed for physiotherapy was permitted on the second postoperative day. On the third day, continuous passive motion (CPM) was started, after which patients were allowed to walk and exercise, as tolerated, under the supervision of a physical therapist.

Evaluation

All assessments were performed by a trained observer; however, the aim and details of the study were not disclosed to the observer, to minimize bias. The assessments carried out included:

• Operating Time: Length of every knee procedure from skin incision to the wound closure.

• Pain Score: Pain scores were measured using a visual analog scale (VAS) of 0 to 10 preoperatively and on postoperative days 1, 3, 5, 7, 14, and 3012.

• Range of Motion (ROM): ROM was measured with a standard handheld goniometer preoperatively and on postoperative days 7, 14, 30, and 9013, 14. Its center of rotation was placed in line with the center of the knee, the fixed arm of the goniometer aligned with the greater trochanter, and the mobile arm aligned with the lateral malleolus. ROM was assessed at the edge of the bed with the patient sitting with his/her thighs parallel and horizontal to the floor. Two trials were performed for all measurements. If the difference was less than 5°, then an average was taken. A third measurement was performed in case the difference was more than 5° and the average of the two closest measurements was taken.

• First Active Straight‐leg Raise Time: The time to achieve the first straight‐leg raise of each leg was recorded.

• Swelling: It was assessed from the change in suprapatellar girth (cm). With the knee fully extended, suprapatellar girth was measured with a standard tape measure at the superior margin of the patella preoperatively and on postoperative days 3, 7, 14, and 30. Postoperative change in suprapatellar girth was the difference compared from postoperative to preoperative values.

• Wound Healing: Postoperatively, the surgical wound was examined for wound length, ooze, soakage, erythema, skin blister, and ecchymosis.

• Deep Vein Thrombosis (DVT): In case of any suspicion of DVT on clinical grounds, a duplex sonography was performed for confirmation of VTE.

• Knee Society Score: Knee Society scores were calculated preoperatively and postoperatively at 3 months and at the last follow‐up.

Statistics

Data were expressed as mean ± standard deviation. Paired t‐tests and χ ²‐tests were used for statistical analysis and a risk rate of P < 0.05 was considered significant. SPSS Statistics 19.0 software (SPSS, Chicago, USA) was used for data analysis.

Results

General Results

The mean age of patients was 67 ± 8 years (range, 58–70 years). The mean height of patients was 161.4 ± 0.4 cm (range, 149.7–178.1 cm); the mean weight was 63.1 ± 14.5 kg (range, 50.2–76.4 kg); and the mean body mass index (BMI) was 28.1 ± 5.5 kg/m² (range, 20.6–36.8 kg/m²). The mean duration of follow‐up was 25 months (range, 19–36 months). A total of 4 cases were lost to follow‐up; 2 sustained severe injury from accidents and lost normal function of the knee, 1 died from pulmonary embolism (PE) 11 days after surgery, and 1 patient relocated to a foreign country. The total operating time in the TG (80 ± 4 min) was approximately 2 min shorter than that in the NG (82 ± 5 min) group; the between‐group difference was statistically significant (P < 0.05).

Visual Analog Scale Scores

Preoperative and postoperative pain scores were measured in both the TG and NG group. Postoperative pain scores in the first operative day both in the TG and NG groups (6.17 ± 0.92 vs 5.32 ± 0.80) were lower than preoperative pain scores (6.53 ± 0.75 vs 6.54 ± 0.76). In the first operative week, pain scores in the TG group were decreased from 6.17 ± 0.92 to 2.45 ± 0.57; pain scores in the NG group were decreased from 5.32 ± 0.80 to 1.95 ± 0.55. Pain scores in the TG group were significantly higher than those in the NG group in the first postoperative week (P < 0.05). After postoperative day 14, no significant between‐group difference was observed in this respect (Table 1).

Table 1.

Visual analog scale scores in the tourniquet (TG) and non‐tourniquet (NG) groups (mean ± standard deviation)

Time‐point	TG	NG	P‐value
Preoperation	6.53 ± 0.75	6.54 ± 0.76	0.946
Day 1	6.17 ± 0.92	5.32 ± 0.80	0.000
Day 3	5.73 ± 0.60	4.92 ± 0.57	0.000
Day 5	4.30 ± 0.59	3.92 ± 0.54	0.001
Day 7	2.45 ± 0.57	1.95 ± 0.55	0.000
Day 14	1.18 ± 0.45	1.14 ± 0.47	0.659
Day 30	0.45 ± 0.53	0.39 ± 0.51	0.558

Range of Motion

The postoperative ROM of two groups within a month was not as high as the preoperative ROM (approximately 110°). Around postoperative day 30, the ROM of the two groups returned to the preoperative level (approximately 110°). The ROM continued to improve gradually and the ROM of the two groups was approximately 123°at postoperative day 90. There was no significant difference in terms of ROM between the two groups, both preoperatively and postoperatively (Table 2).

Table 2.

Range of motion in the tourniquet (TG) and non‐tourniquet (NG) groups (mean ± standard deviation)

Time‐point	TG	NG	P‐value
Preoperation	101.2 ± 8.6	101.4 ± 7.8	0.901
Day 7	80.2 ± 5.5	81.3 ± 5.7	0.319
Day 14	91.3 ± 3.8	92.0 ± 3.9	0.356
Day 30	101.5 ± 6.5	101.7 ± 5.9	0.870
Day 90	123.3 ± 6.5	123.4 ± 6.6	0.938

Time to First Straight‐leg Raise

From day 1 postoperatively, patients were encouraged to raise their leg. Patients in the NG group were able to perform active straight‐leg raise significantly sooner than those in the TG group (3.2 ± 0.8 days vs 3.9 ± 0.8 days, respectively; P < 0.05).

Mean Change in Suprapatellar Girth

Change in suprapatellar girth demonstrated the degree of knee swelling. Mean change in suprapatellar girth in the tourniquet (TG) and non‐tourniquet (NG) groups on days 3 and 7 were 2.89 ± 1.42 versus 1.61 ± 1.23 and 2.52 ± 1.32 versus 1.43 ± 0.89, respectively. The knee swelling with tourniquet was greater than that without use of tourniquet among 2 weeks after TKA (P < 0.05). The between‐group difference was statistically significant at this time point (1.56 ± 1.25 vs 1.20 ± 0.74; P = 0.08). However, no significant difference was observed at 30 days postoperatively (0.90 ± 0.52 vs 0.86 ± 0.48; P = 0.68) (Table 3).

Table 3.

Mean changes in suprapatellar girth in tourniquet (TG) and non‐tourniquet (NG) groups (mean ± standard deviation)

Time‐point	TG	NG	P‐value
Day 3	2.89 ± 1.42	1.61 ± 1.23	0.00
Day 7	2.52 ± 1.32	1.43 ± 0.89	0.00
Day 14	1.56 ± 1.25	1.20 ± 0.74	0.08
Day 30	0.90 ± 0.52	0.86 ± 0.48	0.68

Wound Healing

The average lengths of skin incision at full extension in TG and NG groups were 13.3 cm (range, 12–15 cm) and 12.8 cm (range, 12–14 cm), respectively. The between‐group difference was not statistically significant. The TG group experienced more wound‐related problems as compared to the NG group. The incidence of wound ooze was 63.5% (33/52) in TG and 26.9% (14/52) in the NG group. The incidence of erythema in the TG group (55.8%, 29/52) was higher than that in the NG (28.8%, 15/52) group. At the individual level, the severity of wound ooze or erythema in TG limbs was equal to or greater than that in the NG limbs. Skin blisters occurred in 9 (17.3%) TG knees and 2 (3.8%) in NG knees. Skin ecchymosis occurred in 15 (28.8%) TG knees and in 5 (9.6%) NG knees. One (1.9%) patient developed skin necrosis and deep wound infection in the TG knee, which was treated with antibiotics, irrigation, debridement and change of polyethylene liner.

Deep Vein Thrombosis

Symptomatic DVT events occurred in 7 patients (13.5%), 8 knees (4 each in TG and NG limbs), as confirmed on sonographic examination. There was no significant between‐group difference in this respect.

Knee Society Score

Knee Society scores were determined preoperatively and postoperatively at 3 months and 1 year. Preoperative Knee Society scores (51.2 ± 5.0 vs 51.3 ± 4.8; P = 0.9) and postoperative scores at 3 months (90.3 ± 4.2 vs 90.2 ± 3.9; P = 0.9) and 1 year (93.2 ± 2.3 vs 93.3 ± 2.2; P = 0.8) were comparable between the TG and NG groups, respectively. In TG and NG groups, postoperative Knee Society scores at 3 months (90.3 ± 4.2 vs 90.2 ± 3.9) and 1 year (93.2 ± 2.3 vs 93.3 ± 2.2) were higher than preoperative Knee Society scores (51.2 ± 5.0 vs 51.3 ± 4.8; P < 0.05), but there was no difference between 3 months and 1 year. The Knee Society scores were restored to the highest score in the third month following surgery and remained at this level.

Discussion

The overall benefits and risks of tourniquet use during TKA are still widely debated. Tai et al. emphasize the need for well‐designed randomized controlled trials to clarify the role of tourniquets and to compare the effects of different methods for tourniquet application for TKA7. Much of the current literature is limited to the use of tourniquets in patients undergoing unilateral TKA. The evidence for use of tourniquets for simultaneous bilateral TKA has largely been extrapolated from these studies. As there is a lack of robust evidence related to the use of tourniquets for bilateral TKA, we conducted a prospective controlled study. It is easy to implement a complete control study in the same patient undergoing bilateral simultaneous TKA with tourniquet use only in one limb.

In our study, TKA performed with the use of a tourniquet led to increased pain and swelling during the immediate postoperative period. The group in which tourniquets were used also experienced a higher incidence of wound complications and suffered from a delay in achieving unassisted straight leg raise. These findings are similar to those of previous studies performed in the unilateral TKA setting6, 10, 15. One of the causes of increased postoperative pain could be the direct pressure of tourniquets on local soft tissues and nerves. However, reactive hyperemia after tourniquet deflation causes a 10% increase in limb size and the resultant increase in soft tissue tension around the knee is the likely reason for aggravation of knee pain and swelling16. Tourniquet use could make wound edges hypoxic during the early postoperative period, which affects angiogenesis and migration of macrophages and fibroblasts. It also affects the cellular response to wound healing17, 18. In the TKA with tourniquets, the incidence and severity of wound ooze, erythema, blisters, and ecchymosis was higher. Persistent wound healing problems such as ooze after joint arthroplasty have been shown to be associated with increased risk of infection19, 20. In this study, 1 knee (1.9%) with tourniquet developed deep wound infection, while no infectious complications were observed in the non‐tourniquet group. Because of the low incidence of wound infection, a statistically valid between‐group difference was not feasible. Thigh pain and axonal compression due to tourniquets may lead to postoperative quadriceps weakness and delay in nerve conduction, which may cause a lag in straight‐leg raise time.

There was no significant difference with respect to ROM, DVT, and long‐term Knee Society scores in the two groups, which suggests that the use of tourniquets has no long‐term impact on ROM, VTE rates, and functional outcomes. Studies have shown that unilateral TKA performed without use of a tourniquet facilitates early wound healing, improved ROM, improved Knee Society scores, and lower DVT incidence as compared to that with the use of a tourniquet6, 10, 15. There is asymmetry in the strength between limbs before and many months after unilateral TKA21, 22, 23. Patients with unilateral involvement rely on their “good” or healthy limb to complete functional tasks. The knee function is dependent on the operative technique and several other preoperative factors. In the current study, the ROM and Knee Society scores were better in TKA without a tourniquet and this was attributable to the use of a tourniquet. However, patients who undergo simultaneous bilateral TKA do not have this asymmetry before surgery or at 60 days post surgery24. Patients after simultaneous bilateral TKA attempt to use both limbs in a symmetrical fashion during their recovery and rehabilitation period, which may explain the difference in outcomes from the studies done for unilateral cases25, 26.

Similarly, while evaluating the incidence of VTE for bilateral TKA cases, the development of VTE, which is dependent on multiple risk factors, may not be accurately reflected as an outcome of the study. The period of immobility, surgical time, and postoperative events were similar in both groups, and these risk factors did not impact the incidence of VTE, irrespective of the use of tourniquets in this study. However, more detailed investigations are required to draw definitive conclusions in this regard.

Several clinical trials have shown that the operating time for TKA with tourniquets is almost the same as that for TKA without tourniquets6. In the current study, the mean time saved with the use of a tourniquet was 2 min. The reason is that we just began to perform TKA without a tourniquet in this study and needed more time to control intraoperative bleeding due to limited experience.

Yoon et al. observe an increase in incidence of general complications (5% after simultaneous bilateral TKA vs 0.8% after unilateral TKA), mainly in patients over 70 years of age, with an American Society of Anesthesiologists (ASA) grade of 3 or 427. They recommend that care be taken in elderly patients who are considered high‐risk cases for general anesthesia. Patients ≥70 years of age were excluded from this study, taking into account the previously reported findings in this arena.

A major limitation of this study is the small sample size, which makes generalizations to the overall population tenuous, and increases the probability of type II errors. To detect differences in rare complications such as wound infection and DVT, larger studies are required. Another limitation was the inadequate randomization, because as is standard routine, left knees were operated on first, which may have introduced a bias. Moreover, measurement of intraoperative and postoperative blood loss was not included in our study, which is an important parameter used to evaluate the effectiveness of tourniquets in the published literature. Because drains were inserted into the joint and connected to a Stryker CBC II auto‐transfusion device, it was difficult to precisely quantify the exact site of blood loss. Despite these limitations, our data still provides valuable information regarding tourniquet use in patients undergoing simultaneous bilateral TKA.

In conclusion, the use of tourniquets during simultaneous TKA may save operating time but could also lead to severe postoperative pain, swelling, a high incidence of wound complications, and delayed mean straight‐leg raise time. Some findings of this study were similar to those reported in studies performed in a unilateral TKA setting, wherein the use of tourniquets did not affect the ROM, DVT, and long‐term Knee Society scores. Future studies with large sample sizes are required to assess the influence of the use of tourniquets on the incidence of uncommon complications.