Early functional outcome after subvastus or parapatellar approach in knee arthroplasty is comparable

Functional Outcome of Subvastus versus Medial Parapatellar Approaches for Total Knee Replacement in Patients with Knee Osteoarthritis: A Prospective Cohort Study

Background

Subvastus approach and medial parapatellar approach are two major approaches for total knee replacement (TKR). There is no global consensus on the superiority of either approach in terms of functional outcomes.

Objective

The present study aimed to evaluate the functional outcome of TKR through subvastus approach and medial parapatellar approach by using patient-reported scores at 3-, 6-, and 12-month post-operative follow-ups.

Methods

This prospective cohort follow-up study included patients with knee osteoarthritis who underwent elective primary TKR either through the subvastus or medial parapatellar approaches at King Abdullah Medical City, Makkah city, Kingdom of Saudi Arabia, from January 2019 to December 2022. Scores from the self-reported Oxford Knee Score (OKS) and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) were compared in the two groups of patients at 3-, 6-, and 12-month post-operative follow-ups.

Results

A total of 98 patients were included, of which 37 underwent TKR through the subvastus approach and 61 through the medial parapatellar approach. There was an overall significant change over time in both WOMAC and OKS scores (P < 0.001). Patients who underwent the subvastus approach had significantly higher mean of WOMAC and OKS than patients with the medial parapatellar approach at the 3- and 6-month follow-ups (P < 0.05), but not at the 12-month follow-up.

Conclusions

For TKR, the medial parapatellar approach results in better functional outcomes at the 3- and 6- month follow-up periods compared with the subvastus approach.

Subvastus Approach Supporting Fast-Track Total Knee Arthroplasty Over the Medial Parapatellar Approach: A Systematic Review and Network Meta-Analysis

BACKGROUND

Numerous surgical approaches are being used to perform total knee arthroplasty (TKA). This systematic review and network meta-analysis aimed to compare surgical approaches used in TKA regarding postoperative outcomesat different time points.

METHODS

We performed a literature search from medical database inception until October 2, 2021. We searched for randomized controlled trials (RCTs) investigating patients undergoing TKA and comparing at least 2 surgical approaches regarding early postsurgical clinical outcomes (range of motion [ROM], pain on a visual analog scale, and Knee Society Score [KSS]). We included 33 RCTs in our networks. Using paired and network meta-analysis, we calculated pooled mean differences (MDs) with 95% CIs by comparing surgical approaches to the medial parapatellar method.

RESULTS

The subvastus (SV) method performed the best on days 1 (MD = 6.99; CI: 1.08; 12.89), 3 (MD = 8.00; CI: 2.08; 13.92), 4 (MD = 27.01; CI: 18.09; 35.92), and 6 (MD = 27.22; CI: 18.38; 36.07) for ROM improvement. Regarding the decrease in pain, the mini SV approach offered significantly lower pain values on days 1 (MD = -1.98; CI: -2.93; -1.03), 3 (MD = -0.85; CI: -1.49; -0.22), and 7 (MD = -1.90; CI: -2.23; -1.57). The differences decreased as time passed. Furthermore, the SV and mini-SV methods performed the best regarding total, knee and function KSS.

CONCLUSION

Quadriceps-sparing approaches, especially the SV and mini-SV, are superior to the other approaches in the early postsurgical period, but the differences decrease as time passes.

[A prospective randomized controlled study of total knee arthroplasty via mini-subvastus and conventional approach]

Objective

To compare the clinical and radiographic results between primary total knee arthroplasty (TKA) via mini-subvastus or conventional approach through a prospective randomized controlled study.

Methods

Ninety-four patients (104 knees) undergoing primary TKA between January 2011 and April 2012 were evaluated and randomly divided into 2 groups. Forty-six patients (52 knees) underwent TKA via conventional approach (conventional approach group), and 48 patients (52 knees) underwent TKA via mini-subvastus approach (mini-subvastus approach group). In these patients, 45 cases (51 knees) in conventional approach group and 45 cases (49 knees) in mini-subvastus approach group were followed up and recruited in the final analysis. There was no significant difference in age, gender, body mass index, sides, osteoarthritis grading, American Knee Society Score (KSS), Hospital for Special Surgery (HSS) score, visual analogue scale (VAS), range of motion (ROM) of knee between 2 groups ( P>0.05). The clinical indexes were recorded and analyzed, including the operation time, length of incision, total blood loss, blood transfusion after operation, hospital stay time, the time of performing straight leg raise, incision condition, VAS score, ROM of knee, HSS score, and KSS score, hip-knee-ankle angle (HKA), femoral anatomic axis and the femoral prosthesis joint angle (femoral angle), tibia anatomic axis and tibial prosthesis joint angle (tibial angle), femoral prosthesis flexion angle (FPFA), and posterior slope angle (PSA) of the tibial plateau.

Results

All patients were followed up. The average follow-up time was 66.4 months (range, 60.0-72.5 months) in conventional approach group and 65.6 months (range, 60.0-71.2 months) in mini-subvastus approach group. Compared with the conventional approach group, the incision of mini-subvastus approach group shortened, the operation time prolonged, and the time when patients started straight leg raise exercises was earlier; showing significant differences between 2 groups ( P<0.05). There was no significant difference in hospital stay time, total blood loss, and numbers of blood transfusion between 2 groups ( P>0.05). The complication rate was 8.2% (4/49) in mini-subvastus approach group and 0 in conventional approach group, showing no significant difference between 2 groups ( P=0.054). At 1 and 3 days, the VAS and the ROM of knee in mini-subvastus approach group were significantly better than those in conventional approach group ( P<0.05); but there was no significant difference in above indexes between 2 groups at 14 day ( P>0.05). There was no significant difference in HSS and KSS scores between 2 groups at the 1, 3, 6, 12 months and 3, 5 years ( P>0.05). X-ray film showed no aseptic loosening in all cases. There was no significant difference in the measured values and incidence of abnormal patient of HKA, femoral angle, tibial angle, FPFA, and PSA at last follow-up between 2 groups ( P>0.05).

Conclusion

TKA via mini-subvastus approach is helpful to the early function recovery of knee, but the long-term effectiveness is consistent with TKA via conventional approach. As the limited exposure, TKA via mini-subvastus spproach may has high risk of operative complications.

Lateral parapatellar and subvastus approaches are superior to the medial parapatellar approach in terms of soft tissue perfusion

PURPOSE

The arthrotomy techniques of knee surgery may cause varying degrees of disruption to the tissue blood supply. The aim of this study was to investigate the effects of the medial parapatellar (MPPa), midvastus (MVa), subvastus (SVa) and lateral parapatellar (LPPa) approaches on regional tissue perfusion of the knee.

METHODS

In this experimental study, a total of 28 female rabbits were applied with four different arthrotomy techniques as Group MPPa, Group MVa, Group SVa and Group LPPa. The blood supply of the tissue around the knee was examined by scintigraphic imaging including the perfusion reserve and T _max, and biochemical alteration of the oxidative stress parameters including malondialdehyde (MDA), fluorescent oxidation products (FlOPs), and histopathological findings were evaluated on tissue samples after 3 weeks.

RESULTS

The perfusion reserve was increased in all four groups compared to the healthy, contralateral knees. In the Group LPPa, the vascularity was significantly increased compared to the Group MPPa (p = 0.006). In the examination of biochemical parameters, the increase in MDA levels was statistically significant in the Group MPPa compared with the Group LPPa (p = 0.004), and in the Group MVa compared with the Group LPPa (p = 0.006). The increase in the value of MDA levels was striking in the Group MPPa and Group MVa compared with the control group (p = 0.004, p = 0.004, respectively). The increase in another oxidative stress parameter, the tissue FlOPs levels, was statistically significant in the Group MPPa compared with the control group (p = 0.035).

CONCLUSION

The LPPa and SVa caused less oxidative stress and less disruption of the muscle blood supply, in biochemical and scintigraphic parameters, compared to the MPPa and MVa. Therefore, in clinical practice, the SVa is preferable to the MPPa and MVa in total knee arthroplasty and the LPPa should be preferred more frequently in selected cases with critical soft tissue viability.

Minimally invasive versus conventional approaches in total knee replacement/arthroplasty: A review of the literature

Background

Life expectancy lengthening and aging of population resulted in dramatically increase of patients with osteoarthritis. Total knee arthroplasty is widely used as the gold standard in order to relieve pain, correct deformity and restore function. A contemporary and controversial topic, is that of minimally invasive surgery for TKA. The minimally invasive approaches are based on the concept that they don't violate the extensor mechanism, resulting in earlier functional recovery, shorter hospital stay and enhanced patients' overall satisfaction. The most commonly used MIS approaches in TKA are the subvastus, midvastus and the quadriceps sparing. There is a debate regarding the efficacy and safety of these methods.

Objective

In this article we will review the current literature (randomized controlled trials and systematic reviews/meta-analyses) on MIS compared to traditional approach and analyse their clinical safety, efficacy and long-term results.

Design

Comparison of well-designed studies have tried to demonstrate the advantages/disadvantages, the clinical results and the complications of the MIS approaches compared to the MPP approach.

Results

MIS approaches seem to provide advantages in the immediate post-operative period accompanied by increased reports of complications. Consequently, further investigation based on large well-designed studies with long-term results are warranted to further clarify MIS effectiveness/safety.

Medial subvastus versus the medial parapatellar approach for total knee replacement: A systematic review and meta-analysis of randomized controlled trials

Twenty randomized controlled trials comprising 1893 primary total knee replacements were included in this review.

The subvastus approach conferred superior results for mean difference (MD) in time to regain an active straight leg raise (1.7 days, 95% confidence interval [CI] 1.0 to 2.3), visual analogue score for pain on day one (0.8 points on a scale out of 10, 95% CI 0.2 to 1.4) and total range of knee movement at one week (7°, 95% CI 3.2 to 10.7). The subvastus approach also resulted in fewer lateral releases (odds ratio 0.4, 95% CI 0.2 to 0.7) and less peri-operative blood loss (MD 57 mL, 95% CI 10.5 to 106.4) but prolonged surgical times (MD 9.7 min, 95% CI 3.9 to 15.6).

There was no difference in Knee Society Score at six weeks or one year, or the rate of adverse events including superficial or deep infection, deep vein thrombosis or knee stiffness requiring manipulation under anaesthesia.

This review demonstrates evidence of early post-operative benefits following the subvastus approach with equivalence between approaches thereafter.

Cite this article: EFORT Open Rev 2018;3:78-84. DOI: 10.1302/2058-5241.3.170030.

Anterior vs Posterior Periarticular Multimodal Drug Injections: A Randomized, Controlled Trial in Simultaneous Bilateral Total Knee Arthroplasty

BACKGROUND

Currently, various techniques are used to overcome postoperative pain after total knee arthroplasty. A local analgesic infiltration with periarticular multimodal drug injection (PMDI) is favorable because of its simplicity, safety, and efficacy. The present study compared the efficacy of a PMDI at the anterior vs posterior compartments.

METHODS

Forty-six patients were randomized to receive the PMDI at either the anterior or posterior compartment, with the contralateral knee receiving the PMDI at the opposite compartment. The PMDI injected to the posterior capsule, medial and lateral meniscal remnant, was defined as the posterior compartment injection, whereas the injection to the medial retinaculum, quadriceps muscle, pes anserinus, and retropatellar fat pad was defined as the anterior compartment injection. Pain scores at rest, knee flexion angle, quadriceps function, and drainage blood loss were evaluated in both groups.

RESULTS

The anterior PMDI group had significantly lower pain scores at rest during 96 hours postoperatively. On the day of discharge, 19 patients (41.3%) favored the knee with the anterior PMDI, which was superior to 9 patients (19.6%) who favored the knee with the posterior PMDI. The anterior PMDI demonstrated a superior recovery of quadriceps function during the same period, but there was no significant difference in terms of other parameters.

CONCLUSION

The PMDI at the anterior compartment can reduce pain after total knee arthroplasty with potentially better quadriceps function compared with that in the PMDI at the posterior compartment. We recommend infiltrating the anterior compartment with a greater amount of PMDI than the posterior compartment.

High correlation of the Oxford Knee Score with postoperative pain, but not with performance-based functioning

PURPOSE

The Oxford Knee Score (OKS) is a widely known patient-related outcome measure (PROM) to determine pain and knee functioning before and after total knee arthroplasty (TKA). Self-reported function is mainly influenced by change in pain; therefore, it was hypothesized that the OKS correlates more with pain than with performance-based functioning.

METHODS

In a prospective cohort of 88 patients, who had a cementless mobile-bearing TKA, included in a randomized clinical trial, the correlation between the overall OKS, and its subscales for pain (PCS) and function (FCS), with performance-based functioning using the DynaPort^® Knee Score (DKS), visual analogue scale score for pain (VAS) and the Knee Society Score (KSS) was evaluated. All scores were measured preoperatively, 6 months and 1 year after surgery. Overall change in outcome over time was analysed until 5 years after surgery.

RESULTS

All scores improved over time. The DKS was influenced by sex, preoperative BMI and age. The internal consistency of the OKS PCS increased over time, whereas the OKS FCS remained the same. The mean postoperative OKS FCS showed moderate correlation with the DKS (r = 0.65, p < 0.001), and the mean postoperative OKS and OKS PCS showed high correlation with the VAS (r = -0.79 and r = -0.82, respectively, p < 0.001). The mean postoperative KSS showed high correlations with the OKS (r = 0.80, p < 0.001), the OKS PCS (r = 0.72 p < 0.001) and OKS FCS (r = 0.74, p < 0.001).

CONCLUSION

The postoperative OKS and the OKS PCS showed high correlation with pain, but only the postoperative OKS FCS was well correlated with performance-based functioning. This suggests that the OKS is more related to pain and tells us less on postoperative functioning. This is important when the OKS as PROM is used to evaluate the quality of orthopaedic care of patients with TKA.

LEVEL OF EVIDENCE

III.

The Patient's Perception Does Not Differ Following Subvastus and Medial Parapatellar Approaches in Total Knee Arthroplasty: A Simultaneous Bilateral Randomized Study

This simultaneous bilateral randomized study investigated whether patients would perceive the difference between the subvastus approach (SVA) and the medial parapatellar approach (MPA) after total knee arthroplasty (TKA). In 50 patients scheduled to undergo same-day bilateral TKA, one knee was randomly assigned to SVA and the other to MPA. Patient-reported measures (pain, Western Ontario McMaster University Osteoarthritis Index score, and side preference) and physician-assessed measures (isokinetic muscle strength, range of motion, and Knee Society score) were compared. No differences were observed in the patient-reported measures and physician-assessed measures, with the exception of greater quadriceps strength at postoperative 1 week in knees that underwent SVA. Patients receiving contemporary perioperative management after same-day bilateral TKA do not perceive any difference between knees that underwent SVA or MPA.

Comparison of the quadriceps-sparing and subvastus approaches versus the standard parapatellar approach in total knee arthroplasty: a meta-analysis of randomized controlled trials

Background

The quadriceps-sparing and subvastus approaches are two of the most commonly used minimally-invasive approaches in total knee arthroplasty (TKA). However, the conclusion among studies still remains controversial. The purpose of this meta-analysis was to compare the clinical efficacy of the subvastus and quadriceps-sparing approaches with the standard parapatellar approach in TKA.

Methods

Randomized controlled trials (RCTs) comparing the quadriceps-sparing or subvastus approach with the standard parapatellar approach was identified in the databases of PubMed, the Cochrane library, EMBASE and Web of Science up to July 2014. Two authors extracted the following data: the basic characteristics of patients, the methodological quality and clinical outcomes from the included RCTs independently. RevMan 5.2.7 software was used for meta-analysis.

Results

A total of 19 RCTs (1578 patients) were included for meta-analysis. The results suggested that the quadriceps-sparing approach showed better outcomes in knee society score (KSS) and visual analog score (VAS), but this approach required a longer operative time than the standard parapatellar approach. There were no differences in total complications, wound infection, deep vein thrombosis, blood loss and hospital stay between the quadriceps-sparing and standard approaches. The subvastus approach showed better outcomes in VAS, knee range of motion (ROM), straight leg raise and lateral retinacular release than the standard parapatellar approach. There were no differences in KSS, total complication, wound infection, deep vein thrombosis, blood loss and hospital stay between the quadriceps-sparing and standard approaches.

Conclusions

The current evidence showed that, when compared with the standard parapatellar approach, the quadriceps-sparing approach was associated with better outcomes in KSS and VAS but required a longer operative time, and the subvastus approach was associated with better outcomes in VAS, ROM, straight leg raise and lateral retinacular release.

Increased turn/amplitude parameters following subvastus approach in total knee arthroplasty

PURPOSE

To compare the improvement of the vastus medialis component of the quadriceps muscle electrophysiologically after the subvastus and medial parapatellar approaches in total knee arthroplasty (TKA).

METHODS

A total 26 patients that underwent primary unilateral in TKA were included into the study. TKAs were carried out via subvastus approach in 15 patients, while 11 patients were operated via medial parapatellar approach. The electrophysiological evaluations were carried out blindly with regard to the type of the surgical approach before the operation and at 6th week post-operatively. Non-surgical side was also evaluated as a control. Assessments were patellar tendon reflex analysis, motor unit potential analysis and interference pattern analysis (IPA) including turn-amplitude analysis and IPA during maximum contraction.

RESULTS

When they were compared to the pre-operative values, "the total mean amplitude" and "the mean turn/sec" parameters were significantly increased in group of subvastus approach (p = 0.017 and p = 0.009, respectively) at the post-operative 6th week. We would not be able to find any difference regarding the other electrophysiological parameters. There was also no significant difference between groups.

CONCLUSION

If there was no significant difference in all the electrophysiological parameters, the increase in turn-amplitude analysis in the group of subvastus approach would be considered as an indicator of a faster functional improvement of knee extensor mechanism in these cases.

Non-anatomical capsular closure of a standard parapatellar knee arthrotomy leads to patellar maltracking and decreased range of motion: a cadaver study

PURPOSE

A parapatellar approach disrupts the medial soft tissue stabilizers of the patella. We hypothesized that soft tissue realignment during arthrotomy closure of native cadaveric knees influences patellar kinematics leading to decreased range of motion.

METHODS

Parapatellar arthrotomy was performed in seven native human cadaveric knees that did not contain arthroplasty components. Capsular closure was performed with figure-of-eight sutures in five different positions for each specimen. The capsule was closed anatomically, and then shifted 1.5 or 3 cm distal, or 1.5 or 3 cm proximal relative to surgical markings of the patellar poles. In each closure position, real-time patellar kinematics and range of motion were recorded using a navigation system with patellar tracking function.

RESULTS

Maximum knee flexion was significantly reduced with closure shifted 3 cm proximal (133° ± 8.2°, p < 0.001) or distal (139° ± 6.4°, p < 0.05) compared to anatomical closure (147° ± 4.1°). All closure positions significantly influenced patellar rotation at 45°, 90°, and 120° of flexion (p < 0.001). Closure 1.5 or 3 cm distal increased lateral patellar shift relative to the mechanical axis (p < 0.01). Patellar tilt was significantly decreased at 90° and 120° by closure 3 cm distal (p < 0.01) and at 120° when closed 1.5 cm distal (p < 0.05).

CONCLUSIONS

Imprecise arthrotomy closure significantly impacted patellar kinematics and passive range of motion. Therefore, every effort should be made to provide anatomical closure of the extensor mechanism to preserve native patellar movement kinematics.

LEVEL OF EVIDENCE

V.

Faster recovery after minimally invasive surgery in total knee arthroplasty

PURPOSE

The aim of the study was to identify whether less soft tissue and muscle damage during surgery will allow faster recovery after total knee arthroplasty in comparison with the conventional technique. A limited medial parapatellar approach without tibial medial collateral ligament (MCL) desinsertion was compared with the conventional parapatellar approach.

METHODS

Three hundred patients were randomized either into the minimally invasive group (MIS group) or into the conventional group (CON group). The evaluation was based on the Knee Society Score, range of motion, blood loss, period of hospitalization and postoperative hemoglobin level.

RESULTS

The MIS group showed faster recovery with immediate postoperative full weight-bearing and shorter length of stay (5 vs 10 days). Comparable Knee Society Scores (87.5 vs 88), function scores (90) and alignment (5.5° vs 5.2°) between the CON and MIS group were observed at a follow-up of 24 months. No increase in operative times (52 vs 51 min tourniquet time) or no complications were observed. Reduced blood loss was observed in the MIS group (590 vs 989 ml).

CONCLUSION

The MCL sparing limited medial parapatellar approach allows good surgical exposure, easy extension proximally if necessary, contained closure after surgery with less bleeding, faster recovery, full weight-bearing without aid and most importantly no radiological malalignment.

LEVEL OF EVIDENCE

Therapeutic study, Level II.

Faster quadriceps recovery with the far medial subvastus approach in minimally invasive total knee arthroplasty

PURPOSE

To identify whether less proximal muscle damage during minimally invasive surgery will allow faster recovery after total knee arthroplasty in comparison with a quadriceps incision approach. A limited medial parapatellar approach without tibial medial collateral ligament (MCL) release was compared to a subvastus approach without tibial medial collateral ligament release (far medial subvastus).

METHODS

One hundred and eighty patients were studied. In the mini-parapatellar group, ninety patients and in the far medial subvastus group, the remaining ninety patients were included. The evaluation was based on the Knee Society Score, VAS, morphine consumption, range of motion, time to straight leg raising, walking without aid, stairs and period of hospitalization. Alignment on full leg radiographs and component position on plain films were measured.

RESULTS

The far medial subvastus group showed faster recovery with earlier straight leg raising (1.7 ± 0.5 vs. 2.7 ± 0.4 days), postoperative weight bearing without aid (1.7 ± 0.6 vs. 2 ± 0.8 days) and stair negotiation (3 ± 0.4 vs. 4 ± 0.3 days) resulting in shorter length of stay (4 ± 0.5 vs. 5 ± 1.2 days). Comparable Knee Society Scores (88.5 ± 6.8 vs. 90 ± 10), Function Scores (90 ± 10) and alignment (5.4° ± 2.1° vs. 5.0° ± 2.4°) between the medial parapatellar and far medial subvastus group were observed at a follow-up of 24 months. An increase in operative time for the far medial subvastus was observed (55 ± 10.6 min vs. 67 ± 12 min tourniquet time) but without complications.

CONCLUSION

The MCL sparing far medial subvastus approach allows good surgical exposure, faster straight leg raising, full weight bearing without aid and shorter length of stay with most importantly no radiological malalignment.

LEVEL OF EVIDENCE

Therapeutic study, Level II.

A meta-analysis of the sub-vastus approach and medial parapatellar approach in total knee arthroplasty

PURPOSE

Both sub-vastus (SV) approach and standard medial parapatellar (MP) approach are performed in primary total knee arthroplasty (TKA). Proponents of SV approach stress its importance in decreasing lateral release and preserving function of the extensor mechanism with earlier rehabilitation. The purpose of this study was to summarize the best evidence to compare functional outcomes between SV approach and MP approach in TKA.

METHODS

All relevant randomized controlled trials and quasi-randomized controlled trails comparing SV approach and MP approach in primary TKA were included, and the search strategy followed the requirements of the Cochrane Library Handbook. Methodological quality was assessed, and data were extracted independently by two authors.

RESULTS

Ten studies involving 976 knees, which compared the clinical outcomes after TKA by SV approach and MP approach, were included. The results showed that the SV approach needed less lateral release (RR, 0.37; 95 % CI, 0.17-0.81; P = 0.01) and offered earlier straight leg raise (95 % CI, -3.11 to -0.69; P < 0.01) and superior knee flexion within 1 week postoperation (95 % CI, 1.96-8.20; P < 0.01) with no increase in the duration of surgery.

CONCLUSIONS

The preliminary results can be concluded that SV approach may provide an alternative to the MP approach with earlier rehabilitation and decreased lateral release rates in primary TKA; however, more high-quality randomized controlled trials should be designed to assess the medium and long-term outcomes between these two approaches.

LEVEL OF EVIDENCE

II.

Peri-operative interventions producing better functional outcomes and enhanced recovery following total hip and knee arthroplasty: an evidence-based review

The increasing numbers of patients undergoing total hip arthroplasty (THA) or total knee arthroplasty (TKA), combined with the rapidly growing repertoire of surgical techniques and interventions available have put considerable pressure on surgeons and other healthcare professionals to produce excellent results with early functional recovery and short hospital stays. The current economic climate and the restricted healthcare budgets further necessitate brief hospitalization while minimizing costs.Clinical pathways and protocols introduced to achieve these goals include a variety of peri-operative interventions to fulfill patient expectations and achieve the desired outcomes.In this review, we present an evidence-based summary of common interventions available to achieve enhanced recovery, reduce hospital stay, and improve functional outcomes following THA and TKA. It covers pre-operative patient education and nutrition, pre-emptive analgesia, neuromuscular electrical stimulation, pulsed electromagnetic fields, peri-operative rehabilitation, modern wound dressings, standard surgical techniques, minimally invasive surgery, and fast-track arthroplasty units.

Subvastus versus medial parapatellar approach in total knee arthroplasty: meta-analysis

The subvastus and medial parapatellar approaches are 2 commonly performed techniques in total knee arthroplasty, but the optimal approach for total knee arthroplasty remains controversial. The purpose of this study was to compare the effectiveness and safety of the subvastus vs medial parapatellar approach.The PubMed, Embase, Cochrane Library, Inter-Services Intelligence Web of Knowledge, and Chinese Biomedical Literature databases were searched for eligible quasi-randomized, controlled and randomized, controlled trials. Two authors independently extracted data and assessed the methodological quality of the included studies according to the Cochrane handbook version 5.1.0. Statistical analysis was performed using Review Manager version 5.1 software. Eight randomized, controlled trials and 1 quasi-randomized, controlled trial involving 940 primary total knee arthroplasties were included for meta-analysis. Meta-analysis revealed significant differences favoring the subvastus group in Knee Society Score in terms of function at 4 to 6 weeks (weighted mean difference [WMD]=5.09; 95% confidence interval [CI], 3.08 to 7.09; P<.01) and knee score at 12 months (WMD=2.17; 95% CI, 0.01 to 4.34; P=.05) and lateral retinacular release (odds ratio=0.34; 95% CI, 0.14 to 0.79; P=.01) when compared with the medial parapatellar approach. However, both groups showed similar results in range of motion (P>.05), operative time (WMD=2.15; 95% CI, -3.61 to 7.35; P=.42), blood loss (WMD= -31.07; 95% CI, -91.89 to 29.75; P=.32), hospital stay (WMD= -0.18; 95% CI, -0.67 to 0.31; P=.47), and postoperative complications (P>.05).