Arthroplasty in the Valgus Knee: Comparison and Discussion of Lateral vs Medial Parapatellar Approaches and Implant Selection

Lateral versus medial approach for total knee arthroplasty for valgus knee deformity shows comparable functional outcomes, hip-knee-ankle angle values, and complication rates: a meta-analysis of comparative studies

INTRODUCTION

The aim of this meta-analysis of comparative studies was to update the current evidence on functional and radiographic outcomes and complications between medial and lateral approaches for total knee arthroplasty (TKA) for valgus knee deformity.

MATERIALS AND METHODS

The PubMed, MEDLINE, Scopus, and the Cochrane Central databases were used to search keywords and a total of ten studies were included. The methodological quality of the included studies was assessed. Data extracted for quantitative analysis included the Knee Society score (KSS), range of motion (ROM), surgical time, hip-knee-ankle angle (HKA), and number and types of complications. Random- and fixed-effect models were used for the meta-analysis of pooled mean differences (MDs) and odds ratios (ORs). The Mantel-Haenszel method was adopted.

RESULTS

A total of 1008 patients were identified, of whom 689 and 319 underwent TKA for valgus knee deformity with lateral and medial approach, respectively. The mean age was 70 ± 9.5 and 67.3 ± 9.6 years for the lateral and medial approaches, respectively. The mean follow-up was 37.8 ± 21.9 and 45.9 ± 26.7 months for the lateral and medial approach groups, respectively. Significantly higher functional outcomes were found for the medial approach, as measured by the postoperative KSS (MD = 1.8, 95% CI [0.48, 3.12], P = 0.007) and flexion ROM (MD = 3.12, 95% CI [0.45, 5.79], P = 0.02). However, both of these differences were lower than the minimal clinically important difference. Comparable surgical time and postoperative HKA angle values (MD = 0.22, 95% CI [- 0.30, 0.75], P = 0.40) between the two surgical approaches were found. The incidence of periprosthetic joint infections, fractures, transient peroneal nerve injuries, and deep vein thrombosis was comparable.

CONCLUSION

This meta-analysis of comparative studies showed that when lateral and medial approaches are used for total knee arthroplasty for valgus knee deformity, comparable functional outcomes in terms of the KSS and ROM, surgical time, and postoperative hip-knee-ankle angle values can be expected. Similar rates of periprosthetic joint infection, fracture, and peroneal nerve injury were also found.

LEVEL OF EVIDENCE

I.

PROSPERO REGISTRATION NUMBER ID

CRD42023392807.

Lateral or Medial Parapatellar Surgical Approach to the Valgus Osteoarthritic Knee? A Retrospective Single-Center Study

Aims: Total knee arthroplasty in patients with fixed valgus deformity is a demanding procedure. The aim of this study was to compare the clinical results of using the lateral approach [LA] versus the medial approach [MA] in the treatment of fixed valgus knee deformities. Methods: This single-center study compared the results of 143 consecutive patients with fixed valgus deformity (mean 21.55° valgus, mean age 68.2 years) undergoing LA Total Knee Arthroplasty [TKA] to 50 patients (mean 16.58° valgus, mean age 67.2 years) undergoing MA TKA. The mean follow-up period was 5.1 years (2−10 years). Data was collected from operative notes, routine postoperative visits, and radiological findings. Apart from a radiological evaluation, patients were clinically assessed both pre- and postoperatively using the Knee Society Score [KSS]. Descriptive statistics together with the Kolmogorov-Smirnov test, the Student’s t-test for independent samples, and the Mann-Whitney U test were used. The level of significance in this study was α = 0.05. Results: In the LA group, the KSS Knee was significantly higher than in the MA group [85.31 vs. 77.42, respectively, p-value < 0.001]. The difference was also in the KSS total but with no statistical significance [155.17 vs. 149.22, p-value 0.087]. The surgery time in the LA group was shorter than in the MA group [81 vs. 91 min, respectively, p-value—0.002]. The complication rate after surgery was higher in the MA group than in the LA group (14% vs. 9%, respectively). Conclusions: The lateral approach is a good alternative to the standard medial parapatellar approach in the treatment of fixed valgus knee deformities. A higher postoperative KSS Knee, shorter surgery time, and similar complication rate make the lateral approach a valuable option for treating patients with osteoarthritis and fixed valgus knee deformity.

Lateral approach total knee arthroplasty achieves equivalent patellar tracking in severe valgus deformity compared to mild valgus deformity

PURPOSE

Patellar tracking problems represent 2-10% of complications of total knee arthroplasties (TKA) in valgus knees. However, there are no studies assessing patellar tracking according to the severity of the valgus deformity. The hypothesis was that lateral approach TKA in severe valgus deformity provides equivalent patellar tracking to that in knees with mild valgus deformity.

METHODS

Between 1988 and 2016, 77 TKAs were performed via a lateral approach on a severe valgus deformity (HKA > 195°). Forty-three TKAs performed without tibial tubercle osteotomy and with complete radiological data were included in this study. These were compared with 86 matched TKAs performed via a lateral approach with a mild valgus deformity (HKA between 181° and 190°). Patellar tilt and patellar position were assessed by axial view radiographs at the last follow-up. Complications and clinical outcomes were also evaluated.

RESULTS

The follow-up was mean 52 ± 21 months in the severe valgus group. No significant differences were found between the severe valgus deformity group and the mild valgus deformity groups in patellar tilt (1.6° ± 6.6° versus 1.9° ± 3.2°, respectively) or patellar subluxation. There were complications in 12% (n = 5) and 11% (n = 9) of the severe valgus group and the mild valgus group respectively, without significant difference. There was no significant difference in extensor mechanism complication rate (2.3% versus 4.7%, respectively).

CONCLUSION

Lateral parapatellar approach, without tibial tubercle osteotomy, for TKA in severe valgus deformity results in good patellar tracking. With this approach, the extensor mechanism complication rate in severe valgus deformity was not higher than for mild valgus deformity.

LEVEL OF EVIDENCE

III.

Total Knee Arthroplasty for Valgus Deformity via a Lateral Approach: Clinical Results, Comparison to Medial Approach, and Review of Recent Literature

BACKGROUND

Total knee arthroplasty (TKA) for valgus deformity is a challenge. The standard medial parapatellar approach may not be universally useful for this. We have adopted the lateral approach to valgus knees. Here we describe our experience with this approach, present early results, and compare them to the medial approach.

METHODS

Our institutional registry was queried for all patients with valgus deformity who underwent a TKA via a lateral approach between 2013 and 2016. The registry was also queried for patients with valgus deformity who underwent a TKA through a medial approach in previous years and this data was compared to the study group.

RESULTS

Seventy-nine valgus knees in 72 patients were operated through a lateral approach. Deformity was corrected by 10.8°, from 16.2° to 5.4° (P < .001). Patellar tilt improved from -2.3° to 0.3° (P = .037). Seven implants (9%) were constrained. Mean operating time was 87 minutes (range 53-137). Twenty-five knees in 23 patients were operated via the medial approach. Deformity was corrected by 7.3°, from 13.2° to 5.9° (P < .001). Mean operating time was 137 minutes (range 90-230). Constrained implants were used in 16% of cases. The lateral approach allowed better correction of valgus deformity (10.8 vs 7.3, P = .03) and shorter operative times (87 vs 137 minutes, P < .001).

CONCLUSION

A lateral approach TKA for valgus deformity improves knee alignment and patellar tilt. Compared to the medial approach, it allows better correction of the deformity, shorter operating times, and perhaps less use of constrained implants.

Lateral subvastus approach: A cadaveric examination of its potential for total knee arthroplasty

BACKGROUND

Lateral approaches to total knee arthroplasty (TKA) provide good surgical exposure and may provide greater ease of soft tissue balancing in patients with a valgus deformity; however, little is known about the versatility in non-valgus knees. The present study evaluated if a lateral subvastus approach can achieve adequate surgical exposure while maintaining less soft tissue damage compared with the medial parapatellar approach in knees without any significant deformity.

METHODS

Using paired fresh-frozen cadaveric knees, the present study provides the first specimen-matched, side-by-side comparison of the lateral subvastus approach to the standard medial parapatellar approach to TKA. Ten knees were selected to undergo a lateral subvastus approach; the contralateral knee had a medial parapatellar approach as control. Incision length, surgical exposure and iatrogenic soft tissue damage were compared between the two approaches.

RESULTS

The lateral subvastus approach was successfully performed using an incision length that was not different from that used in the medial parapatellar approach (p > 0.05). The resultant surgical exposure was comparable between approaches (p > 0.05). The risk of the approach included tearing of the vastus lateralis fibers, and/or abrasion of the iliotibial tract/patellar ligament.

CONCLUSIONS

The lateral subvastus approach to TKA provided a comparable method to the standard medial parapatellar approach. Despite adequate exposure, the approach did risk soft tissue injury. Caution needs to be exercised to reduce the risk of iatrogenic injury to the vastus lateralis and surrounding ligaments. The successful implementation in this cadaveric study substantiates the need for further consideration of this approach in clinical practice.

The lateral and medial approach in total arthroplasty for valgus knee: a meta-analysis of current literature

Aim: To compare the lateral and medial approaches of total knee arthroplasty (TKA) in the valgus knee. Materials & methods: An electronic search from the PubMed, Embase, Web of Science and Cochrane library was performed according to 'TKA', 'valgus', 'knee' and 'approach'. Subsequently, manual search was conducted from the reference lists in the identified studies. Results: Four randomized controlled trials and five cohorts were included. Better knee society score and function was noticed in patients after lateral approach. Similar postoperative valgus deformity, operative time, blood loss, Western Ontario and McMaster Universities Osteoarthritis Index, range of motion, pain and total complications in both groups. Conclusion: Compared with the medial approach for TKA in valgus knee, current data shows superior results after TKA by the lateral approach.

Lateral or medial approach for valgus knee in total knee arthroplasty - which one is better? A systematic review

Objective

To identify whether the medial or lateral approach is superior for patients with valgus knees undergoing primary total knee arthroplasty (TKA).

Methods

Studies evaluating the 2 approaches were sourced from the PUBMED, EMBASE, Web of Science, and OVID databases. The quality of included studies was assessed using a modified quality evaluation method, and differences between approaches were systematically reviewed.

Results

Seventeen observational studies were included. The studies were published between 1991 and 2016, and included 5 retrospective studies and 12 prospective studies. Sixteen evaluation methods for the study outcomes were identified. Twelve and eight complication types were identified by studies reporting the lateral and medial approaches for valgus knee, respectively. Several studies showed that pain scores and knee function were superior using a lateral approach.

Conclusion

The lateral approach (combined with a tibial tubercle osteotomy or proximal quadriceps snip) was more useful and safer than the medial approach in the treatment of severe uncorrectable valgus knee deformity in patients undergoing TKA. Most of the available evidence supports the use of a lateral approach provided that the surgeon is familiar with the pathological anatomy of the valgus knee.

Total knee arthroplasty for a valgus deformity angle of >90°: A case report

RATIONALE

Valgus knees are relatively rare in the clinic. Treatments for valgus deviations >90° represent a surgical challenge to achieve a balance between the soft tissue and bone and prevent nerve damage.

PATIENT CONCERNS

A 63-year-old woman with valgus deviations >90° in both knees complained that she had been unable to walk for 50 years.

DIAGNOSES

Congenital malformation valgus deformity.

INTERVENTIONS

Bilateral total knee arthroplasty (TKA) was performed using a rotating hinge knee instrument from Endo-Model for axial correction and stabilization of the joint.

OUTCOMES

The patient fully recovered 3 months after surgery. At the follow-up 6 years after the operation, the function of the knee joint clearly improved. The knee society score (KSS) increased from 35 to 90.

LESSONS

Constrained implants are commonly used to stabilize the joint and correct the bone axis in patients with severe ligamental instability, gross deformity, bone loss, and extreme deviation of the straight leg axis. Intraoperative exploration of the common peroneal nerve and the postoperative flexed position of the knee joints could help prevent nerve injuries.

Short-term and mid-term results of lateral condyle sliding osteotomy in the treatment of valgus total knee arthroplasty: A successful therapy option in Grade 2 valgus total knee arthroplasty

BACKGROUND

Different methods exist for deformity correction and ligament balancing in total knee arthroplasty (TKA) of valgus knees, the sliding osteotomy being one of them. The objective of the current study was to analyze the clinical and radiological short-term and mid-term results of this technique in a larger series.

METHODS

Between June 2007 and May 2014, 98 patients were treated with 98 TKAs and a simultaneous sliding osteotomy. All of them had a Grade 2 fixed valgus deformity (between 10° and 20°). All patients received a mobile-bearing, non-constrained (CR) implant. After prospective inclusion (T1), patients were clinically assessed after one (T2) and 4.5years (±2.1years) (T3), and radiological and Oxford Knee Score (OKS), Knee Society Knee Score (KSS) and the Knee Society Function Score (KSF) were obtained.

RESULTS

All knees were corrected to a mechanical leg alignment within three degrees. Significant improvement of all scores could be measured at T2 and T3. Seven revisions needed to be performed; three of them were procedure-related. In two of them, a problem of capsular closure occurred, while in one the slided epicondyle dislocated after three months. All other revisions were performed because of non-procedure-related problems (e.g. infection).

CONCLUSIONS

Sliding osteotomy of the lateral condyle is a successful option for the treatment of Grade 2 fixed valgus deformity. Due to this technique, higher constraint could be avoided. The results stayed constant over time. The procedure-related complications need to be kept in mind. Long-term results still need to be awaited.

Clinical Outcomes and Survivorship of Lateral Unicompartmental Knee Arthroplasty: Does Surgical Approach Matter?

BACKGROUND

Lateral unicompartmental knee arthroplasty (UKA) has been shown to be an effective procedure to treat isolated lateral compartment osteoarthritis with excellent long-term survivorship. Whether a medial parapatellar approach or a lateral parapatellar approach is superior in lateral UKA is unknown. The purpose of this study was to determine if there is a difference in intermediate-term clinical outcomes in patients undergoing lateral UKA through a lateral vs medial parapatellar approach.

METHODS

We retrospectively reviewed a consecutive series of 65 patients who underwent lateral UKA with a minimum of 2-year follow-up. Fifty-two patients (80%) had a lateral approach and 13 (20%) a medial parapatellar approach. Patient demographics, preoperative and postoperative radiographic findings, need for revision surgery, Knee Society Score, and range of motion were assessed.

RESULTS

Overall survivorship was 94% at a mean of 82 months; with the sample size available for study, there was no difference in survivorship between the groups. There was no difference in Knee Society Score or revision to total knee arthroplasty (5% vs 7%, P = 1.000) between the medial and lateral approach groups. Comparatively, the lateral approach group did have significantly greater postoperative flexion (123.6° vs 116.5°, P = .006) and greater improvement in flexion from preoperative measurements (3.0 vs -8.0°, P = .010).

CONCLUSION

Although our sample size was small, we could not demonstrate a difference in revision rates or clinical outcome scores when comparing a lateral or a medial approach with lateral UKA at intermediate-term follow-up. A lateral approach did have greater postoperative flexion, but its clinical significance remains undetermined.

Keblish's lateral surgical approach enhances patellar tilt in valgus knee arthroplasty

Objective

To compare the clinical and radiological outcomes of conventional medial and lateral approaches for total knee replacement in the valgus osteoarthritic knee.

Methods

In this randomized controlled trial, 21 patients with valgus knee osteoarthritis were randomized to total knee replacement through medial or lateral approach. The primary outcome was radiographic patellar tilt. Secondary outcomes were visual analog scale of pain, postoperative levels of hemoglobin, and clinical aspect of the operative wound.

Results

There were no differences between the groups regarding other clinical variables. Mean lateral tilt of the patella was 3.1 degrees (SD ± 5.3) in the lateral approach group and 18 degrees (SD ± 10.2) in the medial approach group (p = 0.02). There were no differences regarding the secondary outcomes.

Conclusion

Lateral approach provided better patellar tilt following total knee replacement in valgus osteoarthritic knee.