Total knee arthroplasty in severe valgus deformity: interest of combining a lateral approach with a tibial tubercle osteotomy

Total Knee Arthroplasty With Lateral Parapatellar Approach Results in Less Early Postoperative Skin Numbness Than Medial Approach, but No Difference at Mid-Term Follow-Up: A Randomized Control Trial

Background

Anterior skin numbness is a common complication after total knee arthroplasty (TKA) that may impact postoperative functional outcomes. This study aimed to compare skin numbness area, functional outcomes, and patient satisfaction between patients undergoing TKA with a medial parapatellar approach (medial group) and a lateral parapatellar approach (lateral group).

Methods

A prospective randomized study included 68 knees undergoing TKA via the medial parapatellar approach (n = 32) and the lateral parapatellar approach (n = 32) through the midline skin incision. Anterior skin numbness was assessed as the primary outcome using Semmes-Weinstein monofilaments at 6 postoperative timepoints (2 weeks, 6 weeks, 3 months, 6 months, 1 year, and 2 years). Knee range of motion, Knee Injury and Osteoarthritis Outcome Score (KOOS), and patient satisfaction scores were collected. Fifty-nine patients were retrieved at the 2-year final follow-up. Statistical analysis considered repeated outcome measurements with adjusted P-values.

Results

The lateral group had a significantly smaller area of anterior skin numbness at 2 weeks (11.2 vs 20.2 sq.cm.), 6 weeks (8.2 vs 17.2 sq.cm.), and 3 months (7.8 vs 14.4 sq.cm.) postoperatively compared to the medial group. No difference in the area of numbness was found at 6 months, 1 year, and 2 years. Although the lateral group showed significantly higher satisfaction scores (P = .027) and the KOOS symptoms subdomain (P = .018), there were no differences in knee range of motion and other components of KOOS in both groups.

Conclusions

Compared to the medial approach, the lateral parapatellar approach in TKA demonstrates a reduced area of early postoperative skin numbness and expedited 6-month recovery, along with marginally superior patient satisfaction scores. However, both approaches yield comparable outcomes in terms of postoperative knee motion and overall functional outcomes.

Midterm Outcomes After Total Knee Arthroplasty With Lateral Approach for Valgus Knee Deformity in Patients With Rheumatoid Arthritis

Background Valgus knee deformity is often seen in rheumatoid arthritis (RA) cases. Usually, the medial approach has been often utilized for total knee arthroplasty (TKA), even in valgus deformity cases; however, the medial approach is feared to induce further instability in the medial side because it could further break the soft tissue structure, including medial collateral ligament (MCL) and medial patellofemoral ligament (MPFL). Consequently, loosening of the implant, recurrence of valgus knee deformity, and pain due to instability might be induced in the early period after surgery. In this study, a lateral approach for TKA against valgus deformity in RA cases was utilized to avoid further damage on the medial side. Methods Eleven valgus knees in 10 patients with RA (mean age, 61.1 years; mean follow-up, 33.1 months) underwent primary TKA with the lateral approach. Iliotibial band (ITB) dissection and/or peroneal nerve release were performed if necessary. Radiological and clinical investigations were evaluated pre- and postoperatively. Results The average operating time was 106 minutes, which was no longer compared with the time after the medial approach described previously. The extension angle was significantly improved from -15.0 ± 10.2 to -5.5 ± 4.2 degrees (P = 0.03), while the flexion angle showed no significant change (from 111.8 ± 15.9 to 115.0 ± 13.2 degrees). The hip-knee-ankle angle (HKA) was also significantly corrected from -9 ± 4.9 to 0.4 ± 1.7 degrees (P < 0.001). The 2011 Knee Score System (KSS) scores were significantly improved from 6.9 ± 3.4 to 21.5 ± 2.9 (P < 0.001) in symptoms, from 15.6 ± 2.7 to 31.1 ± 4.1 (P < 0.001) in satisfaction, and from 31.5 to 59.5 (P < 0.01) in activity. Conclusion Midterm outcomes after lateral approach TKA were good, and knee alignment was significantly improved. The lateral approach TKA for valgus deformity in patients with RA was not complicated and difficult because it required no additional operating time compared with the medial approach. From the perspective of preventing further damage to the soft tissue structure on the medial side, the lateral approach was meaningful for valgus deformity in patients with RA.

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.

Distribution of the tensor of the vastus intermedius

The tensor of the vastus intermedius (TVI) was first described by Grob et al. in 2016. It originates from the anteroinferior greater trochanter and inserts into the upper patella and receives blood and nerves independently of other muscles. It has been overlooked, but since micro-surgery and detailed rehabilitation treatments are being developed, more research on it is warranted. Here we report on the TVI in a Korean cadaveric study. A total of 58 cadavers (41 males and 17 females) were included. Thighs were examined using a standardized dissection protocol. The quadriceps femoris muscle was identified and its components were defined by blunt dissection. A total of 116 lower limbs were dissected. In 40 of them, there was a separately innervated TVI muscle belly between the fasciae of the vastus lateralis (VL) and the vastus intermedius (VI) muscles. TVIs were classed as independent (ID), VI, and VL types according to the relative relationship between the TVI, VL, and VI, and subdivided into two parts: Part 1 was the proximal muscular portion of the TVI attached to the VL or VI, and part 2 was the distal aponeurotic area. TVIs were analyzed in detail via 58 Korean cadavers. We subdivided them on the basis of their location and association with related muscles. A larger study is needed to clarify the function and prevalence of the TVI.

Soft tissue stabilization of the hinge position in medial closed wedge distal femoral osteotomy: an anatomical study

BACKGROUND

Soft tissue has an important role in stabilizing the hinge point of medial closed wedge distal femoral osteotomy (MCWDFO). However, there are conflicting data on the soft tissue anatomy around the hinge point of MCWDFO and, therefore, further anatomical data are needed. The purposes of the study were to: 1) anatomically analyze the soft tissue around the hinge point of MCWDFO; 2) radiologically define the appropriate hinge point to prevent an unstable hinge fracture based on the result of the anatomical analysis; and 3) histologically analyze the soft tissue based on the result of the anatomical analysis.

METHODS

In 20 cadaveric knees, the capsule attachment of the distal lateral side of the femur was marked with a radiopaque ball bearing. A digital planning tool was used to calculate the area of the marked capsule attachment around the ideal hinge point of MCWDFO on radiographs. The soft tissue around the hinge point was histologically examined and the periosteal thickness was measured and visualized graphically. The graph and radiograph were overlayed using image editing software, and the appropriate hinge position was determined based on the periosteal thickness.

RESULTS

As a result, the periosteal thickness of the distal lateral femur tended to rapidly decrease from the metaphyseal region toward the diaphyseal region. The overlayed graph and radiograph revealed that the periosteal thickness changed in the region corresponding to the apex of the turning point of the femoral metaphysis in all cases.

CONCLUSIONS

In conclusion, the periosteum might support the hinge of MCWDFO within the area surrounded by the apex of the turning point of the femoral metaphysis and the upper border of the posterior part of the lateral femoral condyle.

Preoperative mechanical axis has no influence on reoperation rate in primary rotating-hinge knee arthroplasty

Background

The purpose of the study is to evaluate reoperation rate and its relationship to preoperative mechanical axis of rotating-hinge TKA used as the primary implant in complex knees.

Methods

Patients subjected to primary TKA with a rotating-hinge knee prosthesis due to primary osteoarthritis between 2010 and 2019 were retrospectively reviewed. Preoperative mechanical axis was measured using the last preoperative telemetry x-ray image. Preoperative axis was classified according to the type of deformity (varus or valgus) and its magnitude (0-15°, 16-25° or >25°). Reoperation rate (with or without implant removal) was the primary outcome of the current study. We studied if the preoperative mechanical axis (either varus-valgus, or magnitude of malalignment) was related to implant survival rate.

Results

Forty-two patients were included in the study. Mean follow-up was 51.42 ± 31.88 months. The 83.3% of patients presented a valgus axis while the 16.7% presented a varus axis. Need of reoperation occurred in eight patients (19.0%). However, no patients (0%) required implant removal with revision TKA. No association was seen between the preoperative mechanical axis and risk of reoperation (p = 0.16).

Conclusion

In selected situations that do not permit less constrained implants, primary rotating-hinge arthroplasty could be a good alternative. Risk of reoperation does not seem to depend upon the preoperative mechanical axis when using a rotating-hinge knee prosthesis for primary arthroplasty in non-tumoral complex knees.

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.

Osteotomies and Total Knee Arthroplasty: Systematic Review and Meta-Analysis

Total knee replacement (TKA) is a frequent modality performed in patients with osteoarthritis. Specific circumstances can make it much more difficult to execute successfully, and additional procedures such as osteotomy may be required. The aim of this study was to perform a meta-analysis and systematic review of osteotomies combined with TKA. Methods: In June 2022, a search PubMed, Embase, Cochrane, and Clinicaltrials was undertaken, adhering to PRISMA guidelines. The search included the terms “osteotomy” and “total knee arthroplasty”. Results: Two subgroups (tibial tubercle osteotomy and medial femoral condyle osteotomy) were included in the meta-analysis. Further subgroups were described as a narrative review. The primary outcome showed no significant difference in favor to TTO. Secondary outcomes showed improved results in all presented subgroups compared to preoperative status. Conclusion: This study showed a significant deficit of randomized control trials treated with osteotomies, in addition to TKA, and a lack of evidence-based surgical guidelines for the treatment of patients with OA in special conditions: posttraumatic deformities, stiff knee, severe varus, and valgus axis or patella disorders.

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.

Common peroneal nerve palsy after TKA in valgus deformities; a systematic review

PURPOSE

The aim of this systematic review is to investigate the prevalence of Common Peroneal Nerve Palsy after total knee arthroplasty in valgus deformities. Furthermore, the effectiveness of a peroneal nerve release prior to arthroplasty to prevent the palsy will be investigated.

METHODS

PubMed and Google Scholar were searched. Search terms regarding valgus deformity and total knee arthroplasty were used. Data analysis and extraction were performed using the web application 'Rayyan QCRI' according to PRISMA guidelines and screened according to the inclusion and exclusion criteria.

RESULTS

Twenty-seven studies were included, representing 1397 valgus knees. Knee balancing was performed in 19 studies with lateral soft tissue releases (1164 knees) and 8 studies (233 knees) with an additional osteotomy. Two studies (41 knees) in the lateral soft tissue release group conducted a peroneal nerve release simultaneous to arthroplasty. Common peroneal nerve palsies occurred in 26 cases (1.9%). Overall, no significant difference in palsy ratio between studies was found by using a peroneal nerve release (p = 0.90), between lateral soft tissue releases and osteotomies (p = 0.11) or between releases of specific ligaments.

CONCLUSION

Common peroneal nerve palsies occur in 1.9% of the cases after total knee arthroplasty in valgus deformities. No difference in the number of palsies was seen when using a peroneal nerve release or using different balancing techniques. However, literature about peroneal nerve releases was very limited, therefore, the effectiveness of a peroneal nerve release remains unclear.

LEVEL OF EVIDENCE

LEVEL III: Systematic review.

How Does Robotic-Arm Assisted Technology Influence Total Knee Arthroplasty Implant Placement for Surgeons in Fellowship Training?

Implant malalignment during total knee arthroplasty (TKA) may lead to suboptimal postoperative outcomes. Accuracy studies are typically performed with experienced surgeons; however, it is important to study less experienced surgeons when considering teaching hospitals where younger surgeons operate. Therefore, this study assessed whether robotic-arm assisted TKA (RATKA) allowed for more accurate and precise implant position to plan when compared with manual techniques when the surgery is performed by in-training orthopaedic surgical fellows. Two surgeons, currently in their fellowship training and having minimal RATKA experience, performed a total of six manual TKA (MTKA) and six RATKAs on paired cadaver knees. Computed tomography scans were obtained for each knee pre- and postoperatively. These scans were analyzed using a custom autosegmentation and autoregistration process to compare postoperative implant position with the preoperative planned position. Mean system errors and standard deviations were compared between RATKA and MTKA for the femoral component for sagittal, coronal, and axial planes and for the tibial component in the sagittal and coronal planes. A 2-Variance testing was performed using an α = 0.05. Although not statistically significant, RATKA was found to have greater accuracy and precision to plan than MTKA for: femoral axial plane (1.1° ± 1.1° vs. 1.6° ± 1.3°), coronal plane (0.9° ± 0.7° vs. 2.2° ± 1.0°), femoral sagittal plane (1.5° ± 1.3° vs. 3.1° ± 2.1°), tibial coronal plane (0.9° ± 0.5° vs. 1.9° ± 1.3°), and tibial sagittal plane (1.7° ± 2.6° vs. 4.7° ± 4.1°). There were no statistical differences between surgical groups or between the two surgeons performing the cases. With limited RATKA experience, fellows showed increased accuracy and precision to plan for femoral and tibial implant positions. Furthermore, these results were comparable to what has been reported for an experienced surgeon performing RATKA.

Total Knee Arthroplasty with Concomitant Corrective Tibial Osteotomy Using Patient-Specific Instrumentation and Computed Tomography-Based Navigation in Severe Post-High Tibial Osteotomy Valgus Collapse

We report the case of a 78-year-old woman with lateral knee osteoarthritis and severe valgus knee deformity after high tibial osteotomy. The patient's severe valgus tibial deformity with a valgus angle of 45° was evaluated using a 3-dimensional bone model, and a closing-wedge osteotomy was planned. Combined total knee arthroplasty and closing-wedge tibial osteotomy were performed using patient-specific instrumentation and a computed tomography–based navigation system. A semiconstrained total knee system with a long stem was implanted for fixation of the osteotomy site in the tibia. The patient was able to walk without pain 2 years postoperatively. The Knee Society Score improved from 13 to 73 points, and the functional score improved from 30 to 65 points. This preoperative planning method and the treatment procedure would be beneficial for clinical decision-making and treatment of severe valgus knee deformities.

Incidence of Soft-Tissue Releases, Clinical and Radiological Outcomes of Lateral Parapatellar Approach for Valgus Arthritic Knees: A 4-year Follow-up Study with A Review of Literature

PURPOSE

To analyse the incidence of additional soft tissue releases with the lateral parapatellar approach, and the clinical and radiological outcomes of total knee arthroplasties performed using the lateral parapatellar approach for valgus arthritic knees. A review of the existing literature on valgus arthritic knees undergoing knee replacement was performed and our results compared.

MATERIALS AND METHODS

This is a prospective cohort study of 50 patients operated by this approach. Operation and clinical records were assessed to determine the number and sequence of soft tissue releases. Functional outcome was measured using the Oxford Knee Score. Radiological assessment included measurement of alignment and implant positioning.

RESULTS

46 patients included. Mean follow-up of 4 years. Additional lateral releases were performed in 11 (24%) cases. Mean valgus alignment corrected from 13.1 degrees pre-operatively to 5.7 degrees post-operatively. Oxford Knee Score improved from a mean pre-operative score of 11.9 to a mean post-operative score of 38.3 at final follow-up. Radiographs revealed lateralisation of the tibial component in 4 patients. No immediate or late post-operative wound complications, late instabilities or revisions were observed.

CONCLUSION

Lateral parapatellar approach is highly effective in correcting the valgus deformity with a low incidence of additional soft tissue releases. Medium-term results indicate an excellent functional outcome with no complications.

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.

Revision total knee arthroplasty for patellar dislocation in patients with malrotated TKA components

PURPOSE

Patellar dislocation is a serious complication leading to patient morbidity following total knee arthroplasty (TKA). The cause can be multifactorial. Extensor mechanism imbalance may be present and result from technical errors such as malrotation of the implants. We sought to understand the reasons for post-arthroplasty patellar dislocation and the clinical outcomes of patients in whom it occurs.

METHODS

This is a retrospective cohort study assessing the outcomes of revision surgery for patellar dislocation in patients with component malrotation in both primary and revision TKAs. Patient demographics, dislocation etiology, presurgical deformity, intraoperation component position, complications, reoperation, and Knee Society Scores (KSS) were collected.

RESULTS

Twenty patients (21 knees) were identified. The average time from primary arthroplasty to onset of dislocation was 33.6 months (SD 44.4), and the average time from dislocation to revision was 3.38 months (SD 2.81). Seventeen knees (80.9%) had internal rotation of the tibial component and seven knees (33.3%) had combined internal rotation of both the femoral and tibial components. Fifteen knees (71.4%) were treated with a condylar constrained implant at the time of revision, and five knees were converted to a hinged prosthesis. The average follow-up time was 56 months. During this time, one patient (4.54%) had a recurrent dislocation episode, requiring further surgery. At final follow up, the mean KSS was 86.2.

CONCLUSION

Revision TKA following patellar dislocation for patients with malrotated components was associated with high success rates. After revision surgery, patients had a low recurrence of patellar dislocation, low complication rates, and excellent functional outcomes.

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.

Medial femoral epicondyle upsliding osteotomy with posterior stabilized arthroplasty provided good clinical outcomes such as constrained arthroplasty in primary total knee arthroplasty with severe valgus deformity

PURPOSE

A modified technique referred to as a medial femoral epicondyle upsliding osteotomy was proposed to address severe valgus deformity with unconstrained posterior stabilized (PS) arthroplasty. The study compared the effectiveness of the technique and PS arthroplasty with constrained arthroplasty during primary total knee arthroplasty (TKA).

METHODS

Fifty-three patients presenting with valgus knees with a mean valgus angle (VA) greater than 30° were prospectively randomized and divided into two groups, and both groups received primary TKA. Upsliding osteotomy with PS arthroplasty was performed on the knees of 27 patients (group A), while the remaining 26 patients (group B) received a constrained arthroplasty. The Knee Society function score (KSF), Hospital for Special Surgery knee score (HSS), range of motion (ROM), mediolateral stability and hospitalization expenses were recorded. The hip-knee-ankle angle (HKA), femorotibial angle (FTA) and VA were analysed. Complications were also recorded.

RESULTS

The patients received follow-up care for more than 50 months. The postoperative KSF, HSS and ROM showed marked improvement in both groups (p < 0.05). Radiological assessments showed that HKA, FTA and VA for group A were restored to (179.9 ± 3.0)°, (173.0 ± 2.4)° and (7.0 ± 2.4)°, respectively. For group B, the HKA, FTA and VA were restored to (181.5 ± 2.3)°, (172.5 ± 2.3)° and (7.5 ± 2.3)°, respectively. Only two patients from group A demonstrated mild medial laxity in their knees, and the remaining patients from both groups were stable medially and laterally. However, the total hospitalization expenses and material expenses of group A were less than those of group B because of the more expensive constrained prosthesis and stems. No late-onset loosening or recurrent valgus deformity was displayed.

CONCLUSIONS

Both medial femoral epicondyle upsliding osteotomy with PS arthroplasty and constrained arthroplasty showed good outcomes for the restoration of neutral limb alignment and soft tissue balance, which are demonstrated to be safe and effective techniques for correcting severely valgus knees. Therefore, the clinically important finding of this study is that medial femoral epicondyle upsliding osteotomy with PS arthroplasty can be an alternative method for correcting severe valgus knees.

LEVEL OF EVIDENCE

II.

Total knee replacement on more than 20° valgus: A case control study

INTRODUCTION

Lower-limb valgus deformity exceeding 20° is a particular case, with few publications assessing the impact of the severity of the valgus. The present retrospective case control study compared a series of>20° valgus versus a series of 10-20° valgus, assessing (1) operative data [approach, type of total knee replacement (TKR)], (2) complications and implant survival, and (3) clinical and radiological results.

HYPOTHESIS

Severe valgus deformity requires TKR with greater constraint, incurring a higher rate of complications and poorer implant survival.

MATERIAL AND METHOD

A multicenter retrospective study for the period January 2006 to December 2010 included 53 patients, with a mean age of 72±10 years, presenting>20° valgus. The study series was matched for age and gender with a series of 53 cases of 10-20° valgus. Convexity laxity was greater in the>20° group (p=0.004).

RESULTS

There was no significant inter-group difference in approach (p=0.13). Greater constraint was more frequent in the>20° group (7/53 versus 1/53; p=0.03), independently of convexity laxity or Krackow grade (p=0.14). There were 7 complications (13.2%) in the>20° group and 7 in the 10-20° group (NS). Eight-year survivorship was 95.12% in the>20° group and 94.9% in the 10-20° group (p=0.63). There were no significant differences in Oxford score (p=0.30) or HKA angle (p=0.78) at last follow-up.

CONCLUSION

The study hypothesis was partially confirmed: greater constraint was more frequent in>20° valgus. The number of complications was low, and survival was identical to that of a control group with less severe deformity.

LEVEL OF EVIDENCE

III, retrospectivecase controlstudy.

Navigation-Assisted Total Knee Arthroplasty for a Valgus Knee Improves Limb and Femoral Component Alignment

The purpose of this study was to evaluate the influence of navigation-assisted surgery on radiographic and clinical outcomes after total knee arthroplasty (TKA) for a valgus knee. The authors identified all patients who underwent TKA for a valgus knee between January 2005 and December 2015. Among 83 conventional TKA cases and 55 navigation-assisted TKA cases, propensity score matching was performed for age, sex, body mass index, and preoperative lower limb mechanical axis. Fifty knees were matched to 50 knees. Each case was evaluated regarding lower limb mechanical axis, mechanical lateral distal femoral angle, medial proximal tibial angle, patellar tilt angle, Western Ontario and McMaster Universities Osteoarthritis Index, Knee Society score, and range of motion. Lower outliers of lower limb mechanical axis (30% vs 8%, P=.008) and mechanical lateral distal femoral angle (24% vs 10%, P=.046) were found in navigation-assisted TKA. However, outliers of medial proximal tibial angle, Western Ontario and McMaster Universities Osteoarthritis Index, Knee Society score, and range of motion were similar between the 2 different surgical techniques. Navigation-assisted surgery is correlated with fewer outliers of postoperative lower limb alignment and femoral component position but not tibial component position in TKA for preoperative valgus knee. Clinical outcomes for navigation-assisted TKA were not superior to those for conventional TKA. [Orthopedics. 2019; 42(2):e253-e259.].

Lateral femoral sliding osteotomy in total knee arthroplasty with valgus deformity greater than twenty degrees

PURPOSE

Lateral femoral sliding osteotomy has been reported as an effective technique for total knee arthroplasty (TKA) with significant valgus deformity. This study aims to investigate its utility in TKA with valgus deformity greater than 20°, for which few studies have examined.

METHODS

Consecutive TKA patients with valgus deformity treated with the sliding osteotomy at our institution were retrospectively studied. Constraint implants were not used. Radiological and clinical parameters at follow-ups were compared with those pre-operatively. Radiological parameters included the hip-knee-ankle angle (HKA), the anatomical lateral distal femoral angle (aLDFA), the anatomical lateral plateau ankle angle (aLPTA), and the angle between the femoral mechanical axis and transepicondylar line (femoral transepicondylar angle, FTEA) which was used to reflect concurrent extra-articular valgus and corresponding local alignment. Clinical outcome measures included the Knee Society Score and Functional Score.

RESULTS

Twenty-five patients operated on between July 2011 and February 2017 were enrolled. The average follow-up time was 3.3 (1.5~7.9) years. The pre-operative HKA of 202.7 ± 2.3° (equivalent to valgus of 22.7 ± 2.3°) was reduced to 180.4 ± 2.3° at final follow-ups (P < 0.001). The aLFDA, aLPTA, and FTEA were all significantly improved, with the last one increased from 84.2 ± 1.8° to 89.6 ± 1.6° (t = - 11.35, P < 0.001). All clinical scores were significantly improved without major complications.

CONCLUSIONS

Lateral femoral sliding osteotomy can be effective and safe for TKA with severe valgus deformity greater than 20°.

The Effectiveness of Medial Femoral Epicondyle Up-Sliding Osteotomy to Correct Severe Valgus Deformity in Primary Total Knee Arthroplasty

BACKGROUND

While many surgical techniques can achieve neutral limb alignment and soft tissue balance in severe valgus deformity during total knee arthroplasty (TKA), few published reports concern medial femoral epicondyle up-sliding osteotomy.

METHODS

A prospective investigation was conducted of patients with severe valgus deformities who underwent medial femoral epicondyle up-sliding osteotomy. Clinical measurements, radiological evaluation, and complication data were recorded.

RESULTS

Using posterior-stabilized prostheses, 26 patients underwent 28 TKAs performed by the same surgeon using medial femoral epicondyle up-sliding osteotomy to balance the soft tissue. On average, the follow-up was 54 ± 18 months, and the patient age was 63 ± 11 years. All knees were type II according to Krackow's classification. Varus-valgus knee motion was prohibited with the protection of long-leg knee brace for 3 months. At the last follow-up, the Knee Society function score, Hospital for Special Surgery knee-rating scale, and range of motion were 94 ± 6, 91 ± 4, and 116° ± 8°, respectively. All knees were stable laterally, whereas 2 knees had mild medial laxity and the others were stable. The hip-knee-ankle angle, femorotibial angle, condylar-hip angle, plateau-ankle angle, and valgus angle were 179.9° ± 3.4°, 172.9° ± 3.6°, 89.8° ± 2.5°, 90.2° ± 1.1°, and 7.3° ± 3.5°, respectively.

CONCLUSION

Medial femoral epicondyle up-sliding osteotomy during TKA in patients with severe valgus deformities facilitates the restoration of lower limb alignment, soft tissue balance, and knee stability.

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.

The type of approach does not influence TKA component position in revision total knee arthroplasty - A clinical study using 3D-CT

BACKGROUND

The influence of the surgical approach on the position of the prosthetic components in revision of total knee arthroplasties (rTKA) is still not clear. This study compared the medial parapatellar approach (MPA) and lateral parapatellar subvastus approach with tibial tubercle osteotomy (LPA).

METHODS

Forty-two consecutive patients underwent rTKA from 2006 to 2016 with either MPA (n=21) or LPA (n=21) because of aseptic loosening, infection, malposition or instability (mean follow-up: 41.5months). Revision TKA component position and leg alignment were assessed on three-dimensional CT (3D-CT) images and compared between groups using a t-test (p<0.05). Rotation of rTKA components graded into internal, neutral or external rotation and rates of postoperative complications and revisions were compared between groups with a chi²-test (p<0.05).

RESULTS

Group MPA and LPA showed no significant differences with respect to the femoral component (coronal: 0.6° vs 0.9°; sagittal: 7.5° vs 7.7°; transversal: 0.4° vs -0.2°), tibial component (coronal: 0.1° vs 0.3°; sagittal: 3.1° vs 1.6°; transversal: 6.9° vs 9.3°) and leg alignment (varus: 0.2° vs 1.1°) (p<0.05). Group LPA showed a non-significant (p=0.25) higher incidence of neutrally (28.6% vs 9.5%) and less internally (23.8% vs 38.1%) rotated tibial components. Rates of complication and revisions did not differ significantly.

CONCLUSIONS

In contrast with primary TKA, the two approaches did not influence postoperative rTKA position. This can be explained with the more extensive approach at rTKA and means that no corrections of the orientation of the components are needed performing either MPA or LPA.

Medial parapatellar approach leads to internal rotation of tibial component in total knee arthroplasty

PURPOSE

The purpose of this study was to investigate if the type of approach [medial parapatellar approach (MPA) versus lateral parapatellar approach with tibial tubercle osteotomy (LPA)] influences rotation of femoral and/or tibial component and leg axis in total knee arthroplasty (TKA). It was the hypothesis that MPA leads to an internally rotated tibial TKA component.

METHODS

This study included 200 consecutive patients in whom TKA was performed using either a parapatellar medial (n = 162, MPA) or parapatellar lateral approach with tibial tubercle osteotomy (n = 38, LPA). All patients underwent clinical follow-up, standardized radiographs and computed radiography (CT). TKA components' position and the whole leg axis were assessed on 3D reconstructed CT scans (sagittal, coronal and rotational). Mean values of TKA component position and the whole leg alignment of both groups were compared using a t test. The tibial component was graded as internally rotated (<3° of external rotation (ER)), neutral rotation (equal or between 3° and 6° of ER) and externally rotated (>6° ER). The femoral component was graded as internally rotated [>3° of internal rotation (IR)], neutral rotation (equal or between -3° IR and 3° of ER) and externally rotated (>3° ER).

RESULTS

There was no significant difference in terms of whole leg axis after TKA between both groups (MPA: 0.2° valgus ± 3.4; LPA: 0.0° valgus ± 3.5). Means of tibial component rotation were 2.7° ER ± 6.1 (MPA) and 7.6° ER ± 5.4 (LPA). Patients of group LPA presented a significantly less internally rotated (LPA: 18.4%; MPA: 48.8%) and more externally rotated (LPA: 52.6%; MPA: 22.8%) tibial component (p < 0.001). No significant differences were seen for the femoral component position, tibial valgus/varus and tibial slope.

CONCLUSION

The type of approach (medial versus lateral) significantly influenced tibial TKA component rotation. It appears that a MPA tends to internally rotate the tibial TKA component and a LPA tends to externally rotate the tibial TKA. The anterior cortex should not be used as landmark for tibial TKA component placement when using the lateral approach with tibial tubercle osteotomy.

LEVEL OF EVIDENCE

Retrospective comparative study, Level III.

Ipsilateral stress fracture of the proximal fibula after total knee arthroplasty in a patient with severe valgus knee deformity on a background of Rheumatoid arthritis

•

Stress fracture of the fibula after TKA is extremely rare.

•

A severe valgus knee can be associated with a fibular stress fracture.

•

Fibular fracture after a TKA has a risk of joint instability or aseptic loosening.

•

Watchful waiting and close clinico-radiographic observation is essential in the follow-up of all post-operative TKA patients, especially those whom have had a TKA for a significant valgus knee deformity correction, as in this case.

Introduction

Previous studies have reported a lower extremity stress fracture after total knee arthroplasty (TKA). However, a fibular fracture after TKA is quite rare. We report a case of proximal fibula fracture after TKA in a patient with rheumatoid arthritis (RA).

Presentation of case

A 45 year old woman with RA had severe knee and foot pain with an antalgic gait disturbance. There was a significant joint deformity in many of lower limb joints. Interval bilateral TKAs were performed two weeks apart. Right TKA was performed using a constraint-type prosthesis, through lateral parapatellar approach. Left TKA was performed using a posterior-stabilized (PS) prosthesis through the more commonly employed, medial parapatellar approach. Seven weeks after the right TKA, the patient was found to have an atraumatic proximal fibular fracture. The fracture went on to heal conservatively.

Discussion

The fracture was considered to have occurred after the TKA. The callus appeared eleven weeks after the TKA. The factors that contributed to the fracture were thought to be overload of the fragile bone secondarily to disuse osteopaenia, RA or potentially the significant valgus malalignment correction. The surgical approach, the implant or implantation or the persisting joint deformity, were thought to be contributing factors to the aetiology of the stress fracture. The resultant change in clinical outcome/course is outlined in this case report.

Conclusion

A stress fracture of the proximal fibula has the potential in the aetiology of may cause other stress fractures, joint other instability, and/or malalignment of the total lower extremity.

Tibial tubercle osteotomy (TTO) in total knee arthroplasty, is it worth it? A review of the literature

INTRODUCTION

Tibial tubercle osteotomy (TTO) is a well-established extensile approach to improve joint visualization and implant removal. Despite this, TTO is a challenging technique with a long learning curve and potential pitfalls. Complications are not infrequent, even if performing the correct surgical steps. Aim of this paper is to review the current literature about TTO, its safeness and reliability, and finally the complications rate.

MATERIALS AND METHODS

We performed a systematic review of the available English literature, considering the outcomes and the complications of TTO. The combinations of keyword were "tibial tubercle osteotomy", "total knee arthroplasty", "total knee revision", "outcomes", "complication" and "surgical approach".

RESULTS

From the starting 322 papers available, 26 manuscripts were finally included. Most of the papers show significant improvements in clinical outcomes, both in primary and in revision procedures. Radiographic fragment healing is close to 100%. Related complications can range from 3.8-20%.

CONCLUSION

TTO may be necessary to correct pathological tuberosity position or patella tracking. However, TTO is a challenging technique to improve the surgical approach during total knee arthroplasty. A strict surgical technique can lead to better results and to minimize complications. However, it is not clear if the improved outcome can outweigh the longer surgery and the higher risk of pitfalls.

Classification of lumbopelvic-hip complex instability on kinematics amongst female team handball athletes

OBJECTIVES

The purpose of this study was to examine how lumbopelvic-hip complex (LPHC) stability, via knee valgus, affects throwing kinematics during a team handball jump shot.

DESIGN

LPHC stability was classified using the value of knee valgus at the instant of landing from the jump shot. If a participant displayed knee valgus of 17° or greater, they were classified as LPHC unstable. Stable and unstable athletes' throwing mechanics were compared.

METHODS

Twenty female team handball athletes (26.5±4.7years; 1.75±0.04m; 74.4±6.4kg; experience level: 4.8±4.1 years) participated. An electromagnetic tracking system was used to collect kinematic data while participants performed three 9-m jump shots. The variables considered were kinematics of the pelvis, trunk, and shoulder; and segmental speeds of the pelvis, torso, humeral, forearm, and ball velocities. Data were analyzed across four events: foot contact, maximum shoulder external rotation, ball release, and maximum shoulder internal rotation.

RESULTS

Statistically significant differences were found between groups in pelvis, trunk, humerus, and forearm velocities at all events (p≤0.05). Specifically, the unstable group displayed significantly slower speeds.

CONCLUSIONS

These findings suggest the difference in throwing mechanics are affected by LPHC instability for this select group of female team handball athletes. These differences infer an increased risk of injury in the upper and lower extremities when landing from a jump shot because of the energy losses throughout the kinetic chain and lack of utilization of the entire chain. It is recommended that further investigations also consider muscle activation throughout the throwing motion.

Total Knee Arthroplasty in Severe Valgus Osteoarthritis Excellent Early Results in a 90-Year-Old Patient with a Valgus Deformity of 47°

Grade III valgus deformity (tibiofemoral alignment > 20°) is present in only 0.5% of patients receiving total knee arthroplasty. Furthermore, cases with a valgus deformity exceeding 40° are even rarer. Since they mostly affect elderly, polymorbid patients, successful outcome means a great challenge. We report on a case of a 90-year-old patient with a valgus deformity of 47°. The patient was preoperatively restricted to a wheel chair, unable to walk, and only able to stand for a few seconds. The maximal knee flexion was 100°, and there was an extension deficit of 15°. The WOMAC score was 91; the EQ-5D-5L Index was 0.048. She was treated with a constrained hinged prosthesis. Postoperatively, the axis was 6° valgus. After 3 months of rehabilitation, she was independent using a wheeled walker. The maximal flexion of the knee was 110° and there was no extension deficit. The WOMAC score was 45; the EQ-5D-5L Index was 0.813. This case demonstrates the possibility of a satisfactory result and an improvement in quality of life and mobility with a plausible timetable and with reasonable use of resources even in advanced age and severe valgus deformity.

Correcting severe valgus deformity: taking out the knock

Valgus knee deformity can present a number of unique surgical challenges for the total knee arthroplasty (TKA) surgeon. Understanding the typical patterns of bone and soft-tissue pathology in the valgus arthritic knee is critical for appropriate surgical planning. This review aims to provide the knee arthroplasty surgeon with an understanding of surgical management strategies for the treatment of valgus knee arthritis. Lateral femoral and tibial deficiencies, contracted lateral soft tissues, attenuated medial soft tissues, and multiplanar deformities may all be present in the valgus arthritic knee. A number of classifications have been reported in order to guide surgical management, and a variety of surgical strategies have been described with satisfactory clinical results. Depending on the severity of the deformity, a variety of TKA implant designs may be appropriate for use. Regardless of an operating surgeon's preferred surgical strategy, adherence to a step-wise approach to deformity correction is advised. Cite this article: Bone Joint J 2017;99-B(1 Supple A):60-4.

Clinical Outcomes of Patients with Valgus Deformity Undergoing Minimally Invasive Total Knee Arthroplasty Through the Medial Approach

Objective:

The purpose of this study was to compare the clinical outcomes between patients with a valgus or varus deformity undergoing minimally invasive total knee arthroplasty through the medial approach.

Methods:

The patients were classified into 2 groups according to the preoperative femorotibial angle measured on an anteroposterior long leg roentgenogram. The valgus group comprised of 26 knees in 21 patients with a femorotibial angle <170° (163.5 ± 5.7), and the varus group comprised of 24 knees in 21 patients with a femorotibial angle >190° (195.9 ± 5.5). The following background variables were compared between the groups: age at the time of the operation, sex, causative disease, preoperative femoral mechanical–anatomical angle, and postoperative knee range of motion, Knee Society score, femorotibial angle, and implant position.

Results:

There were significant differences between the valgus and varus groups in the age (68.0 ± 6.9 vs 75.8 ± 6.2 years), percentage of males (23.8% vs 0%), percentage with rheumatoid arthritis (61.9% vs 4.8%), and preoperative femoral mechanical–anatomical angle (6.2 ± 1.0° vs 7.4 ± 2.1°). Clinical outcome variables of postoperative femorotibial angle (173.1 ± 3.9° vs 175.2 ± 1.6°) and α angle (96.6 ± 3.1° vs 95.0 ± 1.9°) also differed.

Conclusion:

It was assumed that over-valgus resection of the femur is a contributory factor to residual valgus alignment. However, knee range of motion and Knee Society score did not differ between the groups. We suggest that minimally invasive total knee arthroplasty through the medial approach is one of the treatment options for patients with valgus deformity.

New insight in the architecture of the quadriceps tendon

BACKGROUND

Published data regarding the structure of the quadriceps tendon are diverse. Dissection of the quadriceps muscle group revealed that beside the rectus femoris, vastus lateralis, vastus intermedius and vastus medialis a fifth muscle component- named the tensor vastus intermedius consistently fused into quadriceps tendon. It can be hypothesized that all these elements of the extensor apparatus of the knee joint must also be represented in the quadriceps tendon. This study investigated the multi-layered quadriceps tendon with special emphasis on all components of the quadriceps muscle group including the newly discovered tensor vastus intermedius.

METHODS

Ten cadaveric lower limbs were dissected. All muscle bellies of the extensor apparatus of the knee joint were identified and traced distally until they merged into the quadriceps tendon. Connections between the different aponeurotic layers of each muscle were studied from origin to insertion. The fusing points of each layer were marked. Their distance to the patella and the distances between the fusing points were measured.

RESULTS

Six elements of the quadriceps muscle group form a tri-laminar structure of the quadriceps tendon. The intermediate layer could be further sub-divided. The elements of the quadriceps tendon are 1. lateral aponeurosis of the vastus intermedius, 2. deep and 3. superficial medial aponeurosis of the vastus intermedius, 4. vastus lateralis, 5. tensor vastus intermedius and 6. rectus femoris. Even with differences in fiber direction - these elements join each other a certain distance proximal to the patella. All elements were fused over a region measuring 13 to 90 mm proximal to the patella. Lateral parts of the vastus intermedius formed the deepest layer of the quadriceps tendon. The superficial and deep layer of the medial vastus intermedius aponeurosis fused 56 mm (range, 30 to 90 mm) and 33 mm (range, 13 to 53 mm) above the patella with the aponeurosis of the tensor vastus intermedius and vastus lateralis respectively. Together they built the two-layered intermediate layer of the quadriceps tendon. The tendon of the rectus femoris forms the superficial layer. The vastus medialis inserts medially in all layers of the quadriceps tendon. Fibers of the lateral muscle components were oriented towards the medial, and fibers of the medial muscle components were oriented towards the lateral femoral condyle.

CONCLUSIONS

The three-layered quadriceps tendon is formed by six elements. These are 1. lateral aponeurosis of the vastus intermedius, 2. deep and 3. superficial medial aponeurosis of the vastus intermedius, 4. vastus lateralis, 5. tensor vastus intermedius and 6. rectus femoris. These elements of the extensor apparatus join each other proximal to the patella in a complex onion-like architecture. Its two-layered intermediate layer shows variable fusions points. The vastus medialis contributes to the quadriceps tendon with its medial insertion into all layers of the quadriceps tendon.

Total knee arthroplasty in valgus knees using minimally invasive medial-subvastus approach

BACKGROUND

An ideal approach for valgus knees must provide adequate exposure with minimal complications due to approach per se. Median parapatellar approach is most commonly used approach in TKA including valgus knees. A medial subvastus approach is seldom used for valgus knees and has definite advantages of maintaining extensor mechanism integrity and minimal effect on patellar tracking. The present study was conducted to evaluate outcomes of total knee arthroplasty (TKA) and efficacy of subvastus approach in valgus knees in terms of early functional recovery, limb alignment and complications.

MATERIALS AND METHODS

We retrospectively reviewed 112 knees with valgus deformity between January 2006 and December 2011. All patients were assessed postoperatively for pain using Visual Analog Scale (VAS) and quadriceps recovery in form of time to active straight leg raising (SLR) and staircase competency and clinical outcomes using American Knee Society (AKS) score and radiographic evaluation with average followup of 40 months (range 24-84 months).

RESULTS

The mean VAS on postoperative day (POD) 1 and POD2 at rest was 2.73 and 2.39, respectively and after mobilization was 3.28 and 3.08, respectively (P < 0.001). The quadriceps recovery was very early and 92 (86.7%) patients were able to do active SLR by POD1 with mean time of 21.98 h while reciprocal gait and staircase competency was possible at 43.05 h. The AKS and function score showed significant improvement from preoperative mean score of 39 and 36 to 91 and 79 (P < 0.001), respectively, and the mean range of motion increased from 102° preoperatively to 119° at recent followup (P < 0.001). The mean tibiofemoral valgus was corrected from preoperative 16° (range 10°-35°) to 5° (range 3°-9°) valgus (P < 0.001).

CONCLUSIONS

Mini-subvastus quadriceps approach provides adequate exposure and excellent early recovery for TKA in valgus knees, without increase in incidence of complications.

Current surgical strategies for total arthroplasty in valgus knee

The majority of orthopaedic surgeons even currently agree that primary total arthroplasty in valgus knees with a deformity of more than ten degrees may prove challenging. The unique sets of bone and soft tissue abnormalities that must be addressed at the time of the operation make accurate axis restoration, component orientation and joint stability attainment a difficult task. Understanding the specific pathologic anatomic changes associated with the valgus knee is a prerequisite so as to select the proper surgical method, to optimize component position and restore soft-tissue balance. The purpose of this article is to review the valgus knee anatomical variations, to assess the best pre-operative planning and to evaluate how to choose the grade of constraint of the implant. It will also be underlying the up-to-date main approaches and surgical techniques be proposed in the English literature both for bone cuts and soft tissue management of valgus knees.

Equivalent results of medial and lateral parapatellar approach for total knee arthroplasty in mild valgus deformities

PURPOSE

When performing total knee arthroplasty (TKA) in valgus knee deformities, a medial or lateral parapatellar approach can be performed, but the lateral approach is often considered technically more difficult. The purpose of this study was to compare intra-operative, early clinical and radiological outcomes of medial and lateral parapatellar approaches for TKA in the setting of moderate knee valgus (<10°).

METHODS

We prospectively analysed 424 knees with pre-operative valgus deformity between 3° and 10° that underwent TKA over an 18-year period; 109 were treated with a medial approach and 315 with a lateral approach. Intra- and post-operative outcomes and complication rates after a minimum follow-up of one year were compared.

RESULTS

Tourniquet (p = 0.25) and surgical (p = 0.62) time were similar between groups. The popliteus tendon was released more frequently in the medial-approach group (p = 0.04), while the iliotibial band was released more frequently in the lateral-approach group (p < 0.001). A tibial tuberosity osteotomy was performed more frequently in the lateral- than medial-approach group (p = 0.003). No significant differences in limb alignment (p = 0.78), or Knee Society Score (KSS) knee (p = 0.32) and function (p = 0.47) results were noted based on surgical approach, and complication rates were similar between groups (p = 0.53).

CONCLUSIONS

Lateral parapatellar approach is a safe and effective surgical technique for performing TKA in moderately valgus knees. These equivalent early results are encouraging for systematic use of the lateral approach in moderately valgus knees.

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

Constrained implants are frequently used for primary total knee arthroplasty (TKA) in patients with moderate and severe genu-valgum (>10˚). This deformity presents corrective challenges for ligament release. The lateral-parapatellar approach has been advocated as an alternative to the traditional medial-parapatellar approach. Claimed advantages include better access for release of tight ligamentous structures, without requirement for release of the medial-collateral ligament. We present our comparative experience of the use of an unconstrained knee-replacement prosthesis inserted by the lateral-parapatellar approach in comparison to a constrained-knee prosthesis inserted via the medial-parapatellar approach. 49 primary total knee-replacements in 48 (6 males, 42 females) patients were performed; 32 through a lateral-parapatellar approach (group L) using an unconstrained-prosthesis and 17 through a medial-parapatellar approach more often requiring a constrained-prosthesis (group M). Mean preoperative valgus angle was 18.5 (range 11-34˚). Patient demographics (p=0.7) and valgus correctability were similar between the two groups. There was no significant difference in the mean post-operative valgus angle. This was 4.2˚ (range 1-9.5˚) using the lateral-parapatellar approach and 5.3˚ (range 0.3-10˚), p=0.12, using the medial-parapatellar approach. Transient common peroneal injury occurred in 2 patients, both group L, in the presence of valgus angles of greater than 20˚. To date no joints have been revised, or are unstable. The use of a lateral-parapatellar approach, appropriate soft tissue release, and an unconstrained PCL-preserving implant, yielded in all cases a stable, well aligned knee arthroplasty. This represents a viable alternative to the constrained-prosthesis using a medial-parapatellar approach in patients with moderate and severe genu-valgum.

Tibial tubercle osteotomy with screw fixation for total knee arthroplasty

This study investigated the efficacy of tibial tubercle osteotomy (TTO) with screw fixation as part of the surgical treatment of primary complicated total knee arthroplasty (TKA) and revision TKA. From January 2000 to April 2011, 15 patients (15 knees) underwent revision TKA and 20 patients (21 knees) underwent primary TKA. The average patient age was 68.7±8.7 years. Patients underwent follow-up at the authors' institution for an average of 60.6±32.9 months. Comparison of preoperative and postoperative Knee Society Scores and Knee Society Functional Scores showed significant postoperative improvement (P<.05). Moreover, postoperative range of motion of the knee improved from 88.5°±33.8° to 104.3°±18.2° (P<.05). Radiographic assessment showed that the average period to bone union was 10.8±5 weeks (range, 5-28 weeks), the average length of the bone fragment was 59.4±5.9 mm, the average width at the proximal end was 18.9±2.9 mm, and the average thickness at the proximal end of the osteotomy was 10.3±1.2 mm. Tibial tubercle osteotomy provided wide exposure for TKA while protecting the extensor mechanism. Solid bone-to-bone fixation was achieved using TTO with 2 screws, and although the overall complication rate was 8.3%, none of the complications were associated with TTO itself. It is recommended that the bone fragment be 60 mm long, 20 mm wide, and 10 mm thick at the proximal end. Appropriate size of the osteotomized bone and solid screw fixation are essential to prevent complications during this procedure.

Lateral parapatellar approach with tibial tubercle osteotomy for the treatment of non-correctable valgus knee osteoarthritis: a retrospective clinical study

BACKGROUND

The aim of this retrospective study was to evaluate the efficacy of a lateral parapatellar approach combined with a tibial tubercle osteotomy (TTO) in patients undergoing total knee arthroplasty (TKA) with non-correctable valgus knee osteoarthritis.

METHODS

We studied 53 consecutive patients (57 knees) who had a primary TKA via lateral parapatellar approach with a global step-cut "coffin" type TTO over a 10-year period. All patients had non-correctable grade II valgus deformity according to the Ranawat classification. The average age of patients was 71 years (45 to 77) and the mean follow-up was 39 months (20 to 98).

RESULTS

Post-surgery, there was a significant improvement in knee extension (p=0.002), flexion (p=0.006), Knee Society Pain and Function Scores (p<0.001) and WOMAC Osteoarthritis Index (p<0.001). The tibiofemoral angle changed from a preoperative median value of 11 deg (10 to 17) to a postoperative value of 3.75 deg (0 to 9). Congruent patellar tracking was observed in all cases. All but one osteotomy united in a median period of 16.7 weeks (9 to 28) and no hardware removal was required. One knee developed infection treated with two-stage reconstruction. A proximal tibial stress fracture also occurred in a patient on long-term bisphosphonate therapy.

CONCLUSION

Lateral parapatellar approach along with TTO is an effective technique for addressing non-correctable valgus knee deformity during TKA.

Total knee arthroplasty in the valgus knee

Valgus knee deformity is a challenge in total knee arthroplasty (TKA) and it is observed in nearly 10% of patients undergoing TKA. The valgus deformity is sustained by anatomical variations divided into bone remodelling and soft tissue contraction/elongation. Bone tissue variations consist of lateral cartilage erosion, lateral condylar hypoplasia and metaphyseal femur and tibial plateau remodelling. Soft tissue variations are represented by tightening of lateral structures: lateral collateral ligament, posterolateral capsule, popliteus tendon, hamstring tendons, the lateral head of the gastrocnemius and iliotibial band. Complete pre-operative planning and clinical examination are mandatory to manage bone deformities and soft tissue contractions/elongations and to decide if a higher constrained prosthesis is necessary. Two different approaches have been described to perform TKA in a valgus knee: the anteromedial approach and the anterolateral one. In valgus knee deformity bone cuts can be performed differently in order to correct low-grade deformities and reduce great deformities. There is still debate in the literature on the sequence of lateral soft tissue release to achieve the best alignment without any instability. The aim of this article is to review the anatomical variations underlying a valgus knee, to assess the best pre-operative planning and to evaluate how to choose the grade of constraint of the implant. We will also review the main approaches and surgical techniques both for bone cuts and soft tissue management. Finally, we will report on our experience and technique.

Efficacy and mid term results of lateral parapatellar approach without tibial tubercle osteotomy for primary total knee arthroplasty in fixed valgus knees

The lateral parapatellar approach, despite providing direct access to the pathological area has not been widely accepted for knee arthroplasty in valgus deformities. We performed a modified lateral (Keblish) approach which consisted of coronal z plasty of lateral retinaculum, quadriceps snip, titrated sequential lateral release and closure with expanded lateral structures in 32 arthritic fixed valgus knees. In 30 knees, either tendon of popliteus or lateral collateral ligament or both could be preserved. At an average follow-up of 5 years, the valgus alignment improved from 25.4° (11°-60°) to 4° (0°-10°) and knee society score improved from 34 to 95 points. There was no late instability or revisions. This approach is rational, eliminates patella maltracking, is applicable in severe deformities and with titrated release, can preserve the posterolateral knee stabilizers that are necessary for long term implant survival.

Lateral Parapatellar Approach Without Tibial Tubercle Osteotomy for Fixed Valgus Deformity Correction in Total Knee Arthroplasty

Introduction

The lateral parapatellar approach provides direct access to the pathological area in a valgus knee deformity and allows sequential titrated release of contracted lateral soft tissues during total knee arthroplasty.

Step 1 Preoperative Planning

Differentiate the flexible and fixed components of the valgus deformity by clinical and radiographic examination.

Step 2 Expansile Lateral Arthrotomy

Open the knee joint from the lateral side by coronal z-plasty of the lateral retinaculum, oblique lateral tenotomy of the quadriceps tendon, and iliotibial band release.

Step 3 Quadriceps Snip and Joint Exposure

Perform a quadriceps snip and expose the knee joint.

Step 4 Tibial and Distal Femoral Cuts

Make proximal tibial and distal femoral cuts in appropriate alignment.

Step 5 Extension Gap Balancing

A rectangular extension gap is the goal.

Step 6 Flexion Gap Balancing

Determine the femoral component size and femoral rotation, and balance the flexion gap.

Step 7 Component Fixation

Confirm tibial rotational alignment, fix the components, and assess patellar tracking.

Step 8 Prosthetic Joint Closure

Perform closure of the prosthetic joint with expanded lateral structures.

Results

Between 2003 and 2009, thirty-two knees with clinical valgus deformity of >10° underwent total knee arthroplasty with an expansile lateral arthrotomy technique¹¹.IndicationsContraindicationsPitfalls & Challenges.

Anterolateral approach using tibial tubercle osteotomy for total knee arthroplasty: can we predict failure?

PURPOSE

The purpose of this study was to identify predictive factors for the occurrence of complications in a consecutive series of patients who underwent step-cut tibial tubercle osteotomy (TTO) and subsequent screw refixation in primary total knee arthroplasty (TKA).

METHODS

Using standardised conventional radiographs, critical parameters including TTO length and depth, proximal abutment width (OT), and orientation and placement of fixation screws were measured in 422 patients (mean age of 71 years and a follow-up time range of one to five years) with two screw fixations.

RESULTS

Medial spatial orientation in the distal screw (11 %, p=0.046), the TTO length (<55.4 mm, p=0.013), the OT width (<14 mm, p=0.002) and the distance of the distal refixation screw from the TKA (<51.7 mm, p=0.003) were significant factors for the occurrence of complications.

CONCLUSIONS

Age, gender, comorbidities, height, weight and/or the body mass index had no significant influence on the occurrence of complications. The TTO-related complication rate was 3 %. Consideration of these key surgical factors leads to improved outcomes.

[Briard's sagittal sliding osteotomy of the lateral condyle in total knee arthoplasty of the severe valgus knee]

OBJECTIVE

Distalization of the insertion of the lateral collateral ligament and popliteus tendon by sliding osteotomy of the lateral femur condyle in order to correct a residual contracture in extension in total knee arthroplasty (TKA) of the severe valgus deformity.

INDICATIONS

Genuine and other valgus deformity of the knee.

CONTRAINDICATIONS

Severe laxity of the medial collateral ligament; common contraindications of joint replacement.

SURGICAL TECHNIQUE

Lateral parapatellar approach and stepwise osteotomy of the tubercle of the tibia, subperiostal release of the lateral contracted structures such as iliotibial band (ITB) and lateral collateral ligament (LCL) in flexion. Tibia first technique, verification of a balanced and stable flexion gap parallel to the epicondylar line. Posterior cruciate ligament (PCL) is preserved. Referencing of the distal femoral cut by a spacer filled only in the medial extension gap. Finishing femoral chamfer cuts. If extension gap remains trapezoidal, further release of the residual lateral contracted structures in extension by means of sliding osteotomy of the lateral condyle and subperiostal release of the capsule and the lateral septum intermusculare is required. Termporary fixation of the lateral condyle by K-wires, resection of the bony excess, trial of test components, definite screw fixation.

POSTOPERATIVE MANAGEMENT

Comparable to TKA in varus deformities by a medioparapatellar approach.

RESULTS

A total of 79 patients (61 women, 18 men, average age 71 years at the time of surgery) with fixed valgus deformities were operated between June 2001 and December 2010 using TKA and sliding osteotomy of the lateral femoral condyle. The preoperative valgus angle under defined valgus and varus stress was 19.5° (8-40), postoperative 4.7° (2-11). Mean medial angle (valgus stress) of the follow-up was 2.1° (0.5-5°), lateral angle (varus stress) 2.3° (0.5-5°). A total of 35 patients were followed-up, at a mean of 73.3 month (24-109 months). The postoperative Knee Society Score was 95 points (56-100 points), while the postoperative Function Score was 90 points (55-100 points) postoperatively. The Oxford Score improved from 22 points (3-43 points) preoperatively to 45 points (21-48 points) postoperatively. One knee had to be revised due to infection, one knee due to non-union of the tibial tubercle. Finally, there were 3 cases with complications associated with the procedure due to the sliding osteotomy of the lateral femoral condyle; all were revised successfully. No conversion to a semi-constrained or constrained knee prosthesis was necessary.

Total knee arthroplasty in severe valgus knee deformity: comparison of a standard medial parapatellar approach combined with tibial tubercle osteotomy

PURPOSE

Primary TKA in valgus knees with a deformity of more than ten degrees may prove challenging, since bone and soft tissue abnormalities make accurate axis restoration, component orientation and joint stability attainment a difficult task. The purpose of this study was to determine which approach is optimal in these patients, by comparing the standard medial parapatellar approach to a lateral parapatellar combined with a tibial tubercle osteotomy (TTO).

METHODS

Forty-four valgus knees--with an axis deviation ranging from 15 to 36 degrees (mean 24°)--were dealt with primary TKA and followed up for a minimum period of 7 years. Lateral parapatellar arthrotomy combined with TTO was performed in 22 individuals (Group A) and a standard medial parapatellar capsulotomy in the remaining patients (Group B). The International Knee Society System Score (IKSS) was used for clinical evaluation. Radiological assessment was performed yearly postoperatively using long films for assessment of the anatomical axis.

RESULTS

The postoperative IKSS scores showed no significant statistical difference between groups A and B (P < 0.05). In the alignment parameter, however, residual valgus deviation occurred in 9% of patients from Group A and in 32% from Group B. No late-onset instability was displayed.

CONCLUSION

Lateral parapatellar approach combined with TTO may prove highly beneficial in significant valgus deformities, as the anatomical axis is restored accurately and soft tissue release of the lateral contracted structures facilitated to an important extent.