Correlation between preoperative and postoperative knee kinematics in total knee arthroplasty using cruciate retaining designs

The authors evaluated the relationships between preoperative and postoperative kinematics in 50 osteoarthritic knees scheduled for cruciate retaining total knee arthroplasty with regards to posterior femoral roll back and external femoral rotation using a navigation system from 10° to 120° of knee flexion. Although posterior femoral roll back was maintained, external femoral rotation was significantly decreased compared to those of the preoperative knee after total knee arthroplasty. However, the amount of posterior roll back and external femoral rotation after total knee arthroplasty were found to be significantly positively related to those measured preoperatively (r = 0.62 and 0.57, respectively). These significant kinematic correlations may explain why preoperative range of knee motion influences range of motion after total knee arthroplasty.     

Reconstruction of a ruptured patellar tendon with achilles tendon allograft following total knee arthroplasty

BACKGROUND: Rupture of the patellar tendon after total knee arthroplasty is a rare and debilitating complication. Proper surgical management of this condition remains controversial. The purpose of this study was to review the results of reconstruction of a ruptured patellar tendon with an Achilles tendon allograft following total knee arthroplasty. METHODS: We reviewed our experience with the use of a fresh-frozen Achilles tendon allograft with an attached calcaneal bone graft to restore extensor function in nine patients with patellar tendon rupture following total knee arthroplasty (five primary and four revision). All patients were examined clinically and radiographically at an average of twenty-eight months. RESULTS: The average knee and functional scores improved from 26 and 14 points, respectively, before the surgery to 81 and 53 points after the surgery. The average extensor lag decreased from 44 degrees preoperatively to 3 degrees postoperatively, and the average range of motion of the knee increased from 88 degrees to 107 degrees. Two grafts failed in the early postoperative period. Both were repaired successfully. Radiographs showed an average proximal patellar migration of 17.8 mm, which did not appear to affect extensor function. CONCLUSIONS: This short-term follow-up study showed that once an Achilles allograft has healed, it can serve as a reliable reconstruction of a ruptured patellar tendon following total knee arthroplasty. This technique may be particularly suited for patients in whom the extensor mechanism was compromised by multiple prior operations. Continued follow-up is necessary to determine the long-term durability of these results.     

Radiographic evaluation of patellofemoral alignment in kinematically aligned total knee arthroplasty: A comparative study with mechanically aligned total knee arthroplasty

BackgroundKinematically aligned total knee arthroplasty (KA-TKA), in which femoral component is placed 3–5° of internal rotation relative to mechanically aligned (MA)-TKA, may have a potential risk of patellofemoral malalignment. This study aimed to assess patellofemoral alignment and compare the data between KA-TKA and MA-TKA, and the relationship with patellofemoral radiographic parameters and patient reported outcomes.MethodsAmong patients who underwent TKA in 2015 and 2016 in our institute, 28 KA-TKAs with a metal-backed patellar component were retrospectively assessed for patellofemoral alignment, and 28 MA-TKAs with a metal-backed patellar component served as controls. A year postoperatively, patellar tilt and shift at 30°, 60°, and 90° knee flexion were measured on Merchant views and compared between the two TKAs. Implant positioning in each patient was assessed based on preoperative CT images and correlations of femoral component positioning with patellar tilt/shift were assessed.ResultsPatellar shift at 30° flexion was significantly greater in KA-TKA than in MA-TKA (p = 0.04), whereas patellar tilt angle was comparable between the two TKAs. No statistical correlation was evident between femoral component positioning and patellar shift/tilt, regardless of knee flexion angle in the two TKAs. Knee Society Score 2011 at 1 year follow-up was comparable in all subcategories between the two TKAs.ConclusionRadiographic analysis of KA-TKA revealed lateral shift of the patella at 30° knee flexion at 1 year postoperatively, however patients with patellar shift were asymptomatic. Further long-term observation is required to examine the impact of KA-TKA on the patellofemoral complication.     

Extensor apparatus reconstruction with Leeds-Keio ligament in total knee arthroplasty

The outcome of reconstruction of patellar tendon rupture in total knee arthroplasty has not been particularly good. Five cases of extensor mechanism rupture in total knee arthroplasty are presented. The surgical technique consisted of suture of the extensor apparatus augmented by a Leeds-Keio ligament. Active extension of -10 degrees was achieved by all the patients with flexion of 90 degrees or more. One superficial infection developed, which required antibiotic treatment. In the course of time, the reconstruction elongated less than 1 cm without significantly affecting function. Although the numbers are small and the complications significant, the final results of this technique have been reasonable. The technique permits early weight bearing and immediate mobilization, which enables an adequate range of motion to be achieved.     

Quantitative Analysis of Patellar Tendon After Total Knee Arthroplasty Using Echo Intensity: A Nonrandomized Controlled Trial of Alpine Skiing

BackgroundDespite the knee extensor weakness, less attention has been paid to the evaluation of patellar tendon after total knee arthroplasty (TKA). We previously observed patellar tendon hypertrophy after TKA. The purpose of this study is to reanalyze these ultrasound data to detect whether brightness mode ultrasound imaging reflects pathological changes of the patellar tendon after TKA.MethodsTwenty-eight participants with post unilateral TKA were assigned to an intervention group or control group. The intervention group underwent a 12-week skiing program. Patellar tendon mechanical properties were obtained by combining isometric dynamometry, ultrasound imaging, and electromyography in operated knee and nonoperated knee. Luminosity ratio (LR) was measured using echo intensity in a relaxed and maximally loaded phase.ResultsBaseline comparisons revealed significant effects of the surgical side (P < .001) and loading phase (P = .017), but no interaction between leg and phase (P < .149). LR of the operated knee was significantly lower than LR of the nonoperated knee in relaxed (P < .001) and maximally loaded phases (P = .003). In addition, there was a significant correlation between LR of maximum phase and isometric knee extension torque (r² = 0.156, P = .038). However, LR was not related to patellar tendon stiffness, Young’s modulus, or strain. There was a significant time effect in knee extension torque, but no time effects on LR and tendon force.ConclusionPatellar tendon LR is decreased along with degenerative change after TKA. Ultrasound imaging provides a promising metric to acquire in vivo patellar tendon pathological assessment after TKA.     

Single-stage procedures for treatment of traumatic patellar osteomyelitis: A retrospective study of 21 patients

IntroductionWe herein report on a series of 21 patients with traumatic patellar osteomyelitis treated by single-stage surgery, and discuss the specific application of single-stage procedures for traumatic patellar osteomyelitis.MethodsWe retrospectively reviewed the medical records of 21 patients with traumatic patellar osteomyelitis treated in our hospital from January 2010 to April 2018. In a single-stage surgery, aggressive debridement was performed together with application of a tissue flap, especially a gastrocnemius flap (for repair of skin/soft tissue defects and treatment of extensor mechanism defects), and internal refixation of the patellar fracture. The knee joint was exercised early after surgery. Long-term follow-up was performed to evaluate the recurrence of osteomyelitis according to clinical and laboratory signs of infection and to measure the active knee range of motion (ROM).ResultsSingle-stage wound treatment was successful in 20 of 21 patients. Treatments included radical debridement together with tissue flap for repair of soft tissue and extensor mechanism defects, and internal refixation of patellar fractures. 14 patients were treated with gastrocnemius flaps. One patient developed recurrent wound infection, which healed after reoperation. At a mean follow-up of 8 ± 2.63 years (range, 3.2–11.4 years), none had developed recurrence. Six patients had nearly full knee ROM (0°–105° to 0°–146°), whereas 11 patients had impaired knee mobility (ROM, 0°–90° to 0°–65°), 3 patients had knee joint stiffness with a ROM of 0°, and 1 patient had knee flexion contracture with a ROM of 78°–130°ConclusionsSingle-stage surgical treatment consisting of various surgical techniques was an acceptable treatment for traumatic patellar osteomyelitis, allowing early exercise of the knee joint. The osteomyelitis did not recur, and most patients’ knee ROM was restored to a certain extent, excluding patients with severe damage to the patellar articular surface and inactive functional exercise.     

Impact of knee flexion on patella length in osteoarthritic patients undergoing total knee arthroplasty

PurposeThis study used magnetic resonance imaging (MRI) to evaluate in vivo preoperative changes in the length of the patellar tendon (LPT) in patients undergoing total knee arthroplasty (TKA). We sought to answer two questions: first, does the LPT change with flexion? Second, does the LPT show a gender-specific pattern?MethodsEighty-five knees in 76 consecutive osteoarthritic patients were evaluated. The age range was 56–90 years (mean 70). The study included 62 females and 14 males. MRI was performed at full extension and at 30°, 60°, 90°, and full flexion.ResultsThere were significantly different patterns between genders (p < 0.001). The main shortenings occurred earlier, at 30°, in females and later, at 60°, in males. In females, LPT values in full extension were significantly longer than those measured at other flexion angles. In male subjects, significant differences in LPT values were found between full extension versus 90° (p < 0.001) and full flexion (p < 0.001), and between 60° versus 90°(p = 0.030) and full flexion (p = 0.030).ConclusionThese differences might influence the gender-specific complications related to the extensor mechanism after TKA. These data provide useful information for surgeons attempting to achieve a satisfactory balance between joint gaps in the patellar reduced position intraoperatively.     

Functional outcomes of total knee arthroplasty in patients with Parkinson's disease: A case control study

BackgroundParkinson's disease is a neurodegenerative condition causing coordination loss in musculoskeletal system. Many studies suggest that total knee arthroplasty in patients with Parkinson's disease has unfavorable treatment results and high complication rates. Our hypothesis was that total knee arthroplasty might be an effective procedure in patients with Parkinson's disease.MethodsParkinson's disease patients who underwent total knee arthroplasty between 2006 and 2018 were retrospectively evaluated. Patients who had Parkinson's disease diagnosis before surgery and who had a minimum follow-up duration of 12 months were included. Secondary knee osteoarthritis patients were excluded. A matched control group was randomly formed. Outcome measures were evaluated by preoperative and postoperative Knee Society Score and joint range of motion values. Comparison was made by means of increase in Knee Society Score and range of motion values. Study group patients were reviewed according to Columbia Classification System to determine disease severity. Stages I-II were accepted as “low-grade” and III-IV-V as “high-grade” disease. Another comparison was made between “low-grade” and “high-grade” patients. Patient who showed disease progression after surgery were also compared to patients without progression.ResultsThere were 13 patients in both groups. In study group, mean preoperative and postoperative Knee Society Score values were 45.4 (±16.8) and 85.6 (±7.60); range of motion values were 93.9° (±17.0°) and 99.5° (±9.37°) respectively with a mean follow-up of 64.5 (±44.7) months. In control group, mean preoperative and postoperative Knee Society Score values were 38.8 (±11.5) and 86.1 (±10.0); range of motion values were 100.4° (±14.6°) and 109.2° (±10.2°) respectively with a mean follow-up of 51.8 (±13.6) months. No significant difference was observed between 2 groups (p > 0.05). Mean preoperative KSS and ROM values were significantly lower in high-grade patients (30.0 (±17.0) and 78.8° (±11.8°) respectively) compared to low-grade patients (52.2 (±11.9) and 100.6° (±14.7°) respectively) (p < 0.05). However, mean increase in KSS and ROM values were significantly higher for high-grade patients (p < 0.05). Mean increase in Knee Society Score and range of motion was 32.4 (±10.9) and 1.00° (±9.46°) respectively in patients with progression, 45.4 (±16.8) and 8.63° (±8.00°) in patients without progression (p > 0.05).ConclusionTotal knee arthroplasty is a successful treatment of knee osteoarthritis in Parkionson's disease patients with similar outcomes compared to general population despite disease severity and progression.     

Osteotomy of the tibial tubercle in complex primary total knee replacement

Objective  Stiffness and severe deformity pose a major challenge in total knee arthroplasty. Numerous techniques have been described to gain exposure and improve knee flexion. Tibial tubercle osteotomy provides excellent and safe exposure of the joint, although mechanical and wound complications have been reported. Materials and methods  We present a series of 32 consecutive complex primary total replacements where an osteotomy of the tibial tubercle was utilised. Results  The patients had a mean follow-up of 2 years and 11 months. Following the procedure, with the exception of one case complicated with deep infection, all of the patients had improved clinically. The mean postoperative range of motion had increased to 102° (give P value < 0.005) and there were no cases of delayed union or non-union. A mechanical complication related to technique occurred in one patient; there were no other cases with a postoperative extension lag. Conclusion  In this challenging population group, we have found a tibial tubercle tuberosity osteotomy to greatly facilitate exposure without compromising the clinical and radiographic outcome.     

Patellar Cut and Composite Thickness: The Influence on Postoperative Motion and Complications in Total Knee Arthroplasty

Background

Little data exist on the influence of patellar thickness on postoperative motion or complications after total knee arthroplasty (TKA). This study addresses the following questions: Is postoperative motion influenced by change in composite patellar thickness? Is change in patellar thickness associated with more complications? And do more complications occur in the knees with a patellar bone remnant (<12 mm) and a native patellar thickness <18 mm?

The composite anterolateral thigh flap for knee extensor and skin reconstruction

The simultaneous reconstruction of a skin defect and lost extensor mechanism of the knee joint is difficult. We present a 31-year-old male who lost the patella and had a 9 × 10 cm skin defect after a total patellectomy for an infected open patellar fracture. A composite anterolateral thigh (ALT) flap including vascularized skin and fascia lata (FL) was elevated. The FL was folded and sutured to the remaining patellar tendon. The skin flap covered the skin defect. The wound healed uneventfully. Thirty months later, the active range of motion of the knee joint was 0°–120° and the extension strength of the knee joint was normal. He could stand on his right leg and walk without assistance. The composite ALT flap is a valuable option in knee reconstruction after a total patellectomy.     

Lateral approach is advantageous in total knee arthroplasty for valgus deformed knee

Introduction

For the total knee arthroplasty in valgus deformed knee, superiority of the medial or lateral approach is still controversial. We compared the short-term result of two approach groups.

Materials and methods

Forty-seven knees in rheumatoid arthritis with valgus deformity from 6° to 24° were randomly divided into two group; medial approach (24 knees) and lateral approach (24 knees). We used Scorpio NRG PS for all knees. Median postoperative periods were 43 months in both groups. We compared the surgical time, and alignment on standing radiograph, range of motion (ROM) pre/postoperatively, and degrees of soft-tissue release procedure, and lateral laxity measured by stress radiograph immediately after operation and at final follow-up.

Result

Pre/postoperative alignment, surgical time, lateral laxity, and preoperative ROM had no significant in two groups; however, postoperative flexion was superior in lateral approach group 123.8°, 109° in medial approach group. All cases required iliotibial band (ITB) release at Gerdy’s tubercle, 83 % ITB at joint level, 21 % lateral collateral ligament (LCL), 17 % popliteus tendon (PT) in medial approach group, and 88 % ITB at Gerdy’s tubercle, 46 % ITB at joint level, 13 % LCL, 4 % PT in lateral approach group.

Discussion

In the valgus knee, lateral structures are tight. Lateral approach can directly adjust the tight structure, and also less vascular compromise to the patella than medial approach with lateral patellar release. Less invasiveness to the quadriceps muscle in lateral approach could result into better range of motion after the surgery.     

Factors affecting range of flexion after total knee arthroplasty

Many factors affect postoperative range of flexion after total knee arthroplasty (TKA). The purpose of this study was to identify the most important factors that affect range of knee flexion after TKA. Sixty-five patients (73 knees) were treated with Genesis II knee replacements. Minimum follow-up was 2 years. Patient demographics (sex, age, body mass index, previous surgery, component type, patella resurfacing, preoperative Knee Society score preoperative range of motion) and radiographic measurements (preoperative tibiofemoral varus/valgus angle, height of the joint line, length of the patellar tendon, shift and tilt angle of the patella) were analyzed statistically. Among these factors, preoperative range of flexion, positively, and preoperative varus/valgus tibiofemoral angle, negatively, affected postoperative range of flexion. The tilt angle of the patella and the tilt angle of the patellar button approached statistical significance in revealing a negative relation with postoperative range of flexion. TKAs in which the patella was not resurfaced tended to lose range of flexion, whereas TKAs in which the patella was resurfaced tended to have no loss of flexion, although the number of TKAs in which the patella was not resurfaced was small. In conclusion, preoperative range of flexion and preoperative varus/valgus tibiofemoral angle affected postoperative range of flexion. The tilt angle of the patella and tilt angle of the patellar button may be factors that affect postoperative range of flexion. Received: September 28, 2000 / Accepted: January 9, 2001     

Influence of hip position on knee flexion angle in patients undergoing total knee arthroplasty

The influence of hip position on knee flexion angle before total knee arthroplasty (TKA) and that after TKA were investigated and compared. Sixty-six patients (70 knees) with osteoarthritis who were undergoing TKA were examined using lateral radiographs of maximum knee flexion angle with the hip joint at 0 degrees extension and 90 degrees flexion. The postoperative rate of decrease in knee flexion angle caused by hip extension was significantly larger compared with the value before surgery. The preoperative rate of decrease in knee flexion angle caused by hip extension showed strong inverse correlation with the preoperative and postoperative knee flexion angle ratio. In conclusion, tightness of the extensor mechanism is present in all knees undergoing TKA and especially has a strong influence on the postoperative flexion angle of the knee.     

Management of extensor mechanism deficit as a consequence of patellar tendon loss in total knee arthroplasty: a new surgical technique

Extensor mechanism disruption is an uncommon but devastating complication of total knee arthroplasty. A new technique of extensor mechanism reconstruction for patellar tendon loss, after total knee arthroplasty, with the help of extensor mechanism composite allograft is described. Four patients with chronic extensor mechanism-deficient total knee arthroplasty were undertaken for revision surgery along with reconstruction of extensor mechanism with an innovative technique using an extensor mechanism composite allograft consisting of a patella-patellar tendon-tibial tubercle. On final follow-up, none of the patients had extensor lag but for 10 degrees of extensor lag in 1 patient only. Providing an environment for bone-to-bone healing both proximally as well as distally and supervised postoperative rehabilitation led to encouraging results in the management of a failed extensor mechanism after total knee arthroplasty.     

Intraoperative soft tissue tension and postoperative range of motion in posterior stabilized total knee arthroplasty

Background

Intraoperative soft tissue tension can significantly impact the range of motion following total knee arthroplasty (TKA). However, the level of impact remains unclear. The purpose of this study was to investigate the relationship between intraoperative soft tissue tension and postoperative range of motion.

Methods

This retrospective study included 504 patients operated with posterior stabilized TKA. During surgery, we adjusted the soft tissue tension from 80 to 160 N for both flexion and extension with the tensor/balancer device and torque driver. Patients were grouped into three categories based on intraoperative soft tissue tension and analyzed with the 1-year postoperative range of motion using one-way analysis of variance (ANOVA). In addition, Pearson’s correlation coefficients were determined to assess the association between intraoperative soft tissue tension and postoperative range of motion.

Results

The absolute tension value at 90° flexion did not affect the postoperative flexion angle (p = 0.61). The absolute tension value at 0° extension did not affect the postoperative extension angle (p = 0.91). Likewise, the difference of tension between flexion and extension did not affect the postoperative flexion angle (p = 0.86). All comparisons did not have the differences in sex, height, weight, body mass index, diagnosis and preoperative range of motion between three groups. No significant correlation was found in each comparison (r = 0.078, r = 0.031, r = ?0.052, respectively).

Conclusions

We did not observe a correlation between intraoperative soft tissue tension adjusted from 80 to 160 N and 1-year postoperative range of motion in posterior stabilized TKA.