Common controversies in total knee replacement surgery: Current evidence

Table 1 Studies comparing posterior cruciate retaining vs posterior cruciate sacrificing total knee replacement methods

Ref.	Type of study	Outcome
Verra et al[15]	Meta-analysis of randomized and quasi-randomized controlled trials, comparing retention with sacrifice of the PCL in primary TKR	No clinically relevant differences found. Range of motion was 2.4° higher in the PCL sacrificing group
Li et al[14]	Meta-analysis of randomized controlled trials comparing posterior cruciate-retaining with posterior stabilized TKA	No differences between the 2 designs
Yagishita et al[13]	Prospective, randomized study comparing high-flexion CR design implanted in one knee and high-flexion PS design implanted in the other knee in simultaneous bilateral TKA	PS prosthesis better in postoperative knee motion, posterior knee pain at passive flexion and patient satisfaction
Seon et al[12]	Prospective randomized trial, comparing in vivo kinematics, range of motion, and functional outcomes in patients who received either a high-flexion cruciate retaining or a high-flexion cruciate substituting TKR	No differences in clinical outcomes. PS TKR superior to CR TKR in weight-bearing maximum flexion and posterior femoral roll-back
Kim et al[11]	Prospective randomized trial, comparing ROM and functional outcome in knees receiving either a high-flexion posterior cruciate-retaining or a high-flexion posterior cruciate-substituting TKR	No differences among groups
Chaudhary et al[10]	Prospective randomized study comparing range of motion of posterior CR vs posterior cruciate-substituting (PS) (TKA)	No differences among groups
Harato et al[9]	Prospective, randomized clinical trial comparing midterm outcomes of posterior CR vs posterior cruciate-substituting (PS) procedures using the Genesis II (TKA)	No significant difference in knee function, postoperative complications and patient satisfaction. Superior ROM in the PS group
Jacobs et al[8]	Systematic review and meta-analysis of prospective randomized trials	Range of motion 8° higher in the posterior-stabilized group compared to the PCL retention group

TKR: Total knee replacement; TKA: Total knee arthroplasty; PCL: Posterior cruciate ligament; PS: Posterior stabilized; CR: Cruciate retaining; ROM: Range of motion.

Table 2 Studies investigating the usefulness of tourniquet use in total knee replacement

Ref.	Type of study	Outcome
Molt et al[27]	Prospective randomized controlled trial. To use a tourniquet or not. To evaluate the early migration, measured by RSA, of cemented knee prosthesis	No differences between the groups regarding the translation or rotation of the components as measured by RSA
Tarwala et al[26]	Randomized trial. To use a tourniquet only during cementation or up to wound closure	No differences in surgical time, pain scores, pain medicine requirements, range of motion, hemoglobin change, or total blood loss
Li et al[25]	Meta-analysis of randomized controlled trials. To use a tourniquet or not	Tourniquet effective for reducing intraoperative blood loss but not for reducing the postoperative blood loss and total blood loss
Olivecrona et al[24]	Randomized controlled trial. Tourniquet cuff pressure based on the patient’s systolic blood pressure or based on the measurement of the limb occlusion pressure	No differences between the groups regarding postoperative pain or complications. Tourniquet cuff pressure based on measurement of the limb occlusion pressure had less wound complications
Mittal et al[23]	Double-blind, randomized controlled trial. Tourniquet application only during cement fixation or continually	Higher risk of transfusion in the short tourniquet use group. No difference in the Oxford knee score or rate of recovery
Ledin et al[22]	Randomized trial of cemented TKR. To use a tourniquet or not	Tourniquet increased postoperative pain and reduced the range of knee motion. Tourniquet group had less overt bleeding
Alcelik et al[21]	Systematic review and meta-analysis of selected randomized controlled trials. To use a tourniquet or not	Tourniquet restricted total blood loss, but was accompanied with significantly higher rate of minor complications
Tai et al[20]	Prospective randomized trial. To use a tourniquet or not	Tourniquet effectively reduced blood and avoided excessive postoperative inflammation and muscle damage. Tourniquet group had slightly more post-op pain
Smith et al[19]	Meta-analysis of randomized and non-randomized trials. Tourniquet use or not	No advantage to using a tourniquet in knee replacement surgery for reduction of transfusion requirements
Rama et al[17]	Meta-analysis of randomized trials. Tourniquet release either before or after wound closure	Tourniquet release before wound closure increases the blood loss. However, tourniquet release after wound closure can increase the risk of early postoperative complications requiring another operation
Ishii et al[16]	Randomized trial in patients who had undergone cementless TKA. Tourniquet release either before or after wound closure	Tourniquet release before wound closure caused a significant increase in total blood loss

RSA: Radiostereometric analysis.

Table 3 Studies investigating the usefulness of continuous passive motion after total knee replacement

Ref.	Type of study	Outcome
Maniar et al[35]	Prospective randomized trial. To use or not to use continuous passive motion post TKR	No benefit from CPM use in immediate functional recovery post-TKR and postoperative ROM. The postoperative knee swelling persisted longer in the CPM group
He et al[34]	Meta-analysis of randomized trials (Cochrane). CPM or not against VTE	No evidence that CPM reduces VTE after TKR
Harvey et al[33]	Meta-analysis of randomized trials (Cohrane). CPM use or not	CPM increases passive knee flexion ROM by mean 2 degrees and active knee flexion ROM by mean 3 degrees. This effect is too small to clinically justify the use of CPM. Weak evidence that CPM reduces the need for manipulation under anesthesia
Alkire et al[32]	Prospective randomized study. CPM use or not for computer-assisted TKA	No statistically significant difference in flexion, edema or drainage, function, or pain between groups 3 mo post-surgery
Lensenn et al[31]	Randomised controlled trial. Effectiveness of prolonged CPM use vs in hospital only use of CPM	No long term difference in ROM or any of the outcome assessments
Leach et al[29]	Prospective randomized trial investigating the effect of CPM on range of knee flexion, lack of extension, pain levels and analgesic use after TKR	No differences among studied groups
Brosseau et al[28]	Meta-analysis of studies examining the effectiveness of CPM	Significant improvement in active knee flexion and analgesic use 2 wk postoperatively with the use of CPM and PT compared with PT alone

CPM: Continuous passive motion; VTE: Venous thromboembolism; PT: Physiotherapy; TKR: Total Knee replacement; ROM: Range of motion.

Table 4 Patella resurfacing vs non-resurfacing in primary total knee replacement

Ref.	Type of study	Outcome
Chen et al[48]	Meta-analysis of randomized controlled trials Patellar resurfacing vs nonresurfacing in primary TKR	Patellar resurfacing reduces the risk of reoperation after TKR. No difference between the 2 groups in terms of anterior knee pain, knee pain score, Knee Society score and knee function score
Pilling et al[44]	Meta-analysis of randomized controlled trials. Patellar resurfacing vs nonresurfacing in primary TKR	The reoperation rate due to anterior knee pain, and the patella-femoral complication rate was significantly higher in the resurfacing group. The knee component of the Knee Society Score was higher in the resurfacing group. No significant difference was observed for the function component of the Knee Society Score or for any other reported knee score
Beaupre et al[43]	Randomized controlled trial. Patellar retention vs patellar resurfacing in primary TKR	No differences among the studied groups
Liu et al[46]	Randomized prospective trial. Patellar reshaping vs resurfacing in TKR	No significant differences between the 2 groups in terms of total Knee Society score, Knee Society pain score, Knee Society function score and anterior knee pain rate
Fu et al[24]	Meta-analysis of randomized controlled trials. Patellar resurfacing vs nonresurfacing	Patellar resurfacing reduce the risk of reoperation after TKR. No difference in anterior knee pain
Breeman et al[39]	Multicenter, randomized controlled trial. Patellar resurfacing or not	No significant difference between the 2 groups regarding functional outcome, reoperation rate, and total health care cost at 5 yr post TKR
Pavlou et al[40]	Meta-analysis of Level-I randomized controlled trials. Patellar resurfacing or not	No significant differences between groups with regard to the incidence of anterior knee pain. Higher rate of reoperations was observed in the non-resurfacing group
He et al[34]	Meta-analysis of randomized trials. Patellar resurfacing or not	Reoperation for patella-femoral problems significantly more likely in the nonresurfacing group. No difference between the 2 groups in terms of anterior knee pain rate, knee pain score, knee society score and knee function score
Burnett et al[37]	Prospective randomized trial. Patella resurfacing vs nonresurfacing in patients undergoing bilateral TKA	No differences regarding the studied parameters
Burnett et al[36]	Prospective randomized trial. Patella resurfacing vs nonresurfacing in patients undergoing bilateral TKA	No differences with regard to range of motion, Knee Score, satisfaction, revision rates, or anterior knee pain

TKR: Total knee replacement; TKA: Total knee arthroplasty.

Table 5 Patellar eversion vs subluxation

Ref.	Type of study	Outcome
Umrani et al[52]	Prospective randomized trial. Patellar eversion or not (mid-vastus approach)	No statistical differences between 2 groups throughout the follow-up periods in recovery of quadriceps force or power and clinical data
Arnout et al[51]	Prospective randomized study. Medial parapatellar arthrotomy with patellar eversion vs same approach without eversion	Patellar dislocation without eversion improved range of motion at 1 yr postoperatively. All other studied parameters were not significantly different
Dalury et al[50]	Prospective randomized trial. Patellar eversion and anterior tibial translation vs patellar subluxation and no tibial translation	No significant differences between the treatment groups at 6 wk, 12 wk or 6 mo after surgery
Walter et al[49]	Prospective, randomized, blinded study. Mid-vastus split with or without patellar eversion vs median parapatellar arthrotomy or a mid-vastus split both without patellar eversion	Significantly earlier return of straight leg raise was noted when patellar eversion was avoided
Reid et al[53]	Prospective randomized double-blinded study. Patients undergoing TKA through a standard medial parapatellar approach assigned to either retraction or eversion of the patella groups	No significant clinical differences in the early to medium term. With patella retraction, there may be an increased risk of damage to the patellar tendon and increased risk in implant malpositioning