Stiffness after total knee arthroplasty

Development and Validation of a Mobile Phone Application for Measuring Knee Range of Motion

Knee range of motion (ROM) is an important indicator of knee function. Outside the clinical setting, patients may not be able to accurately assess knee ROM, which may impair recovery following trauma or surgery. This study aims to validate a smartphone mobile application developed to measure knee ROM compared to visual and goniometer ROM measurements. A knee ROM Android mobile application was developed to measure knee ROM. Patients ≥ 18 years old presenting to an orthopaedic clinic with native knee complaints were approached to participate. Knee ROM was measured bilaterally by an arthroplasty-trained surgeon using (1) vision, (2) goniometer, and (3) the mobile application. Measurements were compared in flexion and extension using a one-way analysis of variance with post hoc Tukey test (alpha = 0.05). Eighty-four knee ROM measurements (40 left, 44 right) were obtained in 47 patients. Median Kellgren-Lawrence grade from available radiographs was grade 3. In flexion, mobile application (117.6 ± 14.7 degrees) measurements were not significantly different from visual (116.1 ± 13.6 degrees) or goniometer (116.2 ± 13.6 degrees) measurements. In extension, mobile application (4.8 ± 7.3 degrees) measurements were significantly different from visual (1.9 ± 4.1 degrees) measurements on post hoc analysis (p < 0.01), while no differences were present compared to goniometer (3.1 ± 5.8 degrees) measurements. Our study found that a mobile application for evaluating knee ROM was noninferior to goniometer-based measurements performed by an arthroplasty-trained surgeon. Future studies will investigate this application's utility in (1) remote patient care, (2) accelerating recovery during rehabilitation, (3) detecting early postoperative complications including arthrofibrosis, and (4) adding additional functionalities to the application to provide more detail-oriented descriptive analyses of patient knee function.

Proteoglycan 4 (Lubricin) and regulation of xanthine oxidase in synovial macrophage as a mechanism of controlling synovitis

BACKGROUND

Synovial macrophages (SMs) are important effectors of joint health and disease. A novel Cx3CR1 + TREM2 + SM population expressing the tight junction protein claudin-5, was recently discovered in synovial lining. Ablation of these SMs was associated with onset of arthritis. Proteoglycan 4 (PRG4) is a mucinous glycoprotein that fulfills lubricating and homeostatic roles in the joint. The aim of this work is to study the role of PRG4 in modulating synovitis in the context of SM homeostasis and assess the contribution of xanthine oxidase (XO)-hypoxia inducible factor alpha (HIF-1a) axis to this regulation.

METHODS

We used Prg4FrtloxP/FrtloxP;R26FlpoER/+, a novel transgenic mouse, where the Prg4Frt allele normally expresses the PRG4 protein and was designed to flank the first two exons of Prg4 with a flippase recognition target and "LOXP" sites. Inducing flippase activity with tamoxifen (TAM) inactivates the Frt allele and thus creates a conditional knockout state. We studied anti-inflammatory SMs and XO by quantitative immunohistochemistry, isolated RNA and studied immune pathway activations by multiplexed assays and isolated SMs and studied PRG4 signaling dysfunction in relation to glycolytic switching due to pro-inflammatory activation. Prg4 inactivated mice were treated with oral febuxostat, a specific XO inhibitor, and quantification of Cx3CR1 + TREM2 + SMs, XO immunostaining and synovitis assessment were conducted.

RESULTS

Prg4 inactivation induced Cx3CR1 + TREM2 + SM loss (p < 0.001) and upregulated glycolysis and innate immune pathways in the synovium. In isolated SMs, Xdh (p < 0.01) and Hif1a (p < 0.05) were upregulated. Pro-inflammatory activation of SMs was evident by enhanced glycolytic flux and XO-generated reactive oxygen species (ROS). Febuxostat reduced glycolytic flux (p < 0.001) and HIF-1a levels (p < 0.0001) in SMs. Febuxostat also reduced systemic inflammation (p < 0.001), synovial hyperplasia (p < 0.001) and preserved Cx3CR1 + TREM2 + SMs (p < 0.0001) in synovia of Prg4 inactivated mice.

CONCLUSIONS

PRG4 is a biologically significant modulator of synovial homeostasis via inhibition of XO expression and downstream HIF-1a activation. PRG4 signaling is anti-inflammatory and promotes synovial homeostasis in chronic synovitis, where direct XO inhibition is potentially therapeutic in chronic synovitis.

Chronic post-surgical pain after total knee arthroplasty: a narrative review

Total knee arthroplasty (TKA) is an efficacious treatment for end-stage knee osteoarthritis, often accompanied by severe postoperative pain. In certain patients, this pain can persist for over 3 months and is referred to as chronic post-surgical pain (CPSP). Postoperative persistent pain has emerged as a significant and noteworthy issue impacting patient quality of life following TKA. The etiology of CPSP after TKA is multifaceted. Peripheral or central sensitizations resulting from inflammatory reactions, nerve injury, and neurobiological mechanisms are the primary mechanisms contributing to chronic persistent pain after TKA. Preoperative, intraoperative, and postoperative factors can induce pain sensitization. Once CPSP occurs after TKA, it significantly hampers patient recovery with challenging treatment options. Currently, among the preventive and therapeutic strategies for chronic pain after TKA, it is widely believed that early comprehensive preventive treatment to prevent acute to chronic pain transition can substantially reduce the incidence of CPSP following TKA. In recent years, studies have investigated perioperative strategies aimed at reducing the occurrence of persistent pain after TKA. This article provides an overview of advancements in understanding the pathogenesis, high-risk factors, and preventive measures for chronic pain following TKA. We hope that this review will guide future research directions on CPSP after TKA while contributing to clinical perioperative pain management.

Predicting Outcome of Total Knee Arthroplasty by Cluster Analysis of Patient-Reported Outcome Measures

BACKGROUND

Total knee arthroplasties (TKAs) exhibit an 8 to 30% risk of suboptimal outcomes, resulting in persistent symptoms, individual morbidity, and revision surgery, prompting a contemporary focus on risk reduction and outcome improvement. This study introduces hierarchical cluster analysis as a way of preoperatively assessing the likelihood of success/failure of TKA based on several patient-reported outcome measures (PROMs), which have been analyzed both intact and with component questions as individual variables.

METHODS

The study utilized data on 1,433 TKAs from The Miriam Hospital's Function and Outcomes Research for Comparative Effectiveness in Total Joint Replacement registry. Outcomes are expressed as Knee Injury and Osteoarthritis Outcome Score pain and function scores. Criteria for success/failure were developed with an integrative, anchor-based, minimum clinically important difference. Preoperative and postoperative PROMs were studied by cluster analysis.

RESULTS

There were three sequential cluster analyses that revealed clusters of patients, based upon preoperative patient responses that were predictive of surgical outcomes. Clusters varied most significantly in their responses to individual component questions of preoperative PROMs. Extracting and combining the clinically meaningful patient-reported component questions yielded a new, and clinically relevant, outcome measure that has the potential to preoperatively predict postoperative outcomes of TKA.

CONCLUSIONS

In contrast to a single medical, psychological, or social variable, cluster analysis offers the opportunity to develop a whole-patient profile that reflects the contextual interactions of sociodemographic and clinical variables in predicting outcomes. In the context of determining clinical meaningfulness, cluster analysis has one of its major strengths.

Late Manipulation under Anesthesia after Total Knee Arthroplasty: Improved Range of Motion and a Low Complication Rate

The purpose of this study was to evaluate outcomes of late manipulation under anesthesia (MUA) for stiffness performed from ≥12 weeks to more than a year after primary total knee arthroplasty (TKA). A total of 152 patients receiving MUA ≥12 weeks after primary TKA from 2014 to 2021 were reviewed. The primary outcome measured was change in range of motion (ROM). We tracked intraoperative complications and the need for repeat MUA or open procedure for continued stiffness after initial MUA. Three subgroups were analyzed: Group 1 included 58 knees between 12 weeks and 6 months after TKA, Group 2 included 44 knees between 6 and 12 months after TKA, and Group 3 included 50 knees ≥12 months after TKA. Analysis included descriptive statistics and univariate analysis, with α <0.05. Groups 1 to 3 all significantly increased their overall ROM by 20.9, 19.2, and 22.0 degrees, respectively. All groups significantly increased their flexion and extension from preoperatively. Group 1 had one intraoperative supracondylar femur fracture (1.7%) requiring open reduction and internal fixation, and five patients required repeat MUA or open procedure (8.6%). Group 2 had no intraoperative fractures, and five patients required repeat MUA or open procedure (11.4%). Group 3 had one intraoperative tibial tubercle avulsion fracture managed conservatively (2.0%) and one repeat MUA (2.0%). Late MUA resulted in significantly improved ROM in all groups. ROM improved more as the time from index TKA increased, although statistically insignificant. Repeat MUA or open procedure rate decreased with MUA ≥12 months from TKA, although statistically insignificant. The overall intraoperative fracture risk was 1.3%.

Adductor Catheter Insertion Through the Knee Arthrotomy: Can This Technique Be as Safe and Effective as Ultrasound-Guided Insertion?

BACKGROUND

Early postoperative pain following total knee arthroplasty remains challenging. We devised a technique for inserting a continuous catheter intraoperatively in the adductor canal and aimed to compare its efficacy and safety with that of an ultrasound-guided anesthetist-administered continuous catheter.

METHODS

This single-center, single-surgeon, prospective, interventional, randomized controlled trial included 330 patients, who were randomized into two groups with similar preoperative status and demographics. There were 18 patients who met the exclusion criteria. Group A (n = 152) received the block from an anesthetist, while group B (n = 160) received the block from the surgeon. Patients had visual analog scale scores, range of motion, maximum ambulation distance, time to straight leg raise, length of stay, and results from a 10-meter walk test, Timed Up and Go test, and a 30-second chair test measured preoperatively and at 6, 12, and 24 hours postoperatively by a physiotherapist and pain nurse blinded to the group assignment.

RESULTS

The visual analog scale scores at 12 hours postsurgery were significantly lower in group B (0.66) compared to group A (0.77, P = 0.04). Range of motion (supine flexion 43.2 versus 43.1, P = 0.72; sitting flexion 90.0 versus 89.9, P = 0.17), Timed Up and Go test (126.1 versus 136.9, P = 0.9), 10-meter walk test (163.5 versus 165.4, P = 0.7), 30-second chair test (3.7 versus 3.8, P = 0.7), time to active straight leg raise (4.0 versus 4.1, P = 0.3), time to ambulation with walker (4.02 versus 4.05, P = 0.3), and length of stay (1.44 versus 1.39, P = 0.49) showed no significant differences between the groups. No serious complications were reported in either group.

CONCLUSIONS

We concluded that this technique was at least as safe and effective as the USG-guided, anesthetist-administered adductor canal catheter.

Proteoglycan 4 (Lubricin) and Regulation of Xanthine Oxidase in Synovial Macrophage as A Mechanism of Controlling Synovitis

Background

Synovial macrophages (SMs) are important effectors of joint health and disease. A novel Cx3CR1 + TREM2 + SM population expressing the tight junction protein claudin-5, was recently discovered in synovial lining. Ablation of these SMs was associated with onset of arthritis. Proteoglycan 4 (PRG4) is a mucinous glycoprotein that fulfills lubricating and homeostatic roles in the joint. The aim of this work is to study the role of PRG4 in modulating synovitis in the context of SM homeostasis and assess the contribution of xanthine oxidase (XO)-hypoxia inducible factor alpha (HIF-1α) axis to this regulation.

Methods

We used Prg4 FrlioxP/FrtloxP ;R26 FlPoER/+ , a novel transgenic mouse, where the Prg4 Frt allele normally expresses the PRG4 protein and was designed to flank the first two exons of Prg4 with a flippase recognition target and "LOXP" sites. Inducing flippase activity with tamoxifen (TAM) inactivates the Frt allele and thus creates a conditional knockout state. We studied anti-inflammatory SMs and XO by quantitative immunohistochemistry, isolated RNA and studied immune pathway activations by multiplexed assays and isolated SMs and studied PRG4 signaling dysfunction in relation to glycolytic switching due to pro-inflammatory activation. Prg4 inactivated mice were treated with oral febuxostat, a specific XO inhibitor, and quantification of Cx3CR1 + TREM2 + SMs, XO immunostaining and synovitis assessment were conducted.

Results

Prg4 inactivation induced Cx3CR1 + TREM2 + SM loss (p < 0.001) and upregulated glycolysis and innate immune pathways in the synovium. In isolated SMs, Xdh (p < 0.01) and Hif1a (p < 0.05) were upregulated. Pro-inflammatory activation of SMs was evident by enhanced glycolytic flux and XO-generated reactive oxygen species (ROS). Febuxostat reduced glycolytic flux (p < 0.001) and HIF-1α levels (p < 0.0001) in SMs. Febuxostat also reduced systemic inflammation (p < 0.001), synovial hyperplasia (p < 0.001) and preserved Cx3CR1 + TREM2 + SMs (p < 0.0001) in synovia of Prg4 inactivated mice.

Conclusions

PRG4 is a biologically significant modulator of synovial homeostasis via inhibition of XO expression and downstream HIF-1a activation. PRG4 signaling is anti-inflammatory and promotes synovial homeostasis in chronic synovitis, where direct XO inhibition is potentially therapeutic in chronic synovitis.

Nearly 14-Fold Increased Risk of Manipulation Under Anesthesia After Total Knee Arthroplasty When Previous Contralateral Total Knee Arthroplasty Required Manipulation Under Anesthesia

BACKGROUND

Stiffness remains a common complication after primary total knee arthroplasty (TKA). Manipulation under anesthesia (MUA) is the gold standard treatment for early postoperative stiffness; however, there remains a paucity of data on the risk of MUA after primary TKA if a prior contralateral TKA required MUA.

METHODS

We performed a retrospective review of 3,102 patients who had staged primary TKAs between 2016 and 2021. The mean body mass index was 33 (range, 18 to 59) and the mean age was 67 years (range, 24 to 91). The mean preoperative range of motion for the first TKA was 2 to 104°, and for the contralateral TKA was 1 to 107°. The primary outcomes were MUA following first and second primary TKAs. Multivariable Poisson regressions were used to evaluate associations between risk factors and outcomes.

RESULTS

The rate of MUA after the first TKA was 2.6% (n = 83 of 3,102) and 1.3% (n = 40 of 3,102) after the contralateral TKA. After adjustment, there was a nearly 14-fold higher rate of MUA after the second TKA if the patient had an MUA after the first TKA (relative risk, 13.80; 95% CI [confidence interval], 7.14 to 26.66). For the first TKA, increasing age (adjusted risk ratio [ARR], 0.65; 95% CI, 0.50 to 0.83) and increasing body mass index (ARR, 0.65; 95% CI, 0.47 to 0.90) were associated with lower risk for MUA. For the second TKA, increasing age was associated with a lower risk of MUA (ARR, 0.60; 95% CI, 0.45 to 0.80).

CONCLUSIONS

For patients undergoing staged bilateral TKA, patients who undergo MUA following the first primary TKA are nearly 14-fold more likely to undergo an MUA following the contralateral primary TKA than those who did not have an MUA after their first TKA.

IL24 Expression in Synovial Myofibroblasts: Implications for Female Osteoarthritis Pain through Propensity Score Matching Analysis

(1) Introduction: Despite documented clinical and pain discrepancies between male and female osteoarthritis (OA) patients, the underlying mechanisms remain unclear. Synovial myofibroblasts, implicated in synovial fibrosis and OA-related pain, offer a potential explanation for these sex differences. Additionally, interleukin-24 (IL24), known for its role in autoimmune disorders and potential myofibroblast production, adds complexity to understanding sex-specific variations in OA. We investigate its role in OA and its contribution to observed sex differences. (2) Methods: To assess gender-specific variations, we analyzed myofibroblast marker expression and IL24 levels in synovial tissue samples from propensity-matched male and female OA patients (each n = 34). Gene expression was quantified using quantitative polymerase chain reaction (qPCR). The association between IL24 expression levels and pain severity, measured by a visual analog scale (VAS), was examined to understand the link between IL24 and OA pain. Synovial fibroblast subsets, including CD45-CD31-CD39- (fibroblast) and CD45-CD31-CD39+ (myofibroblast), were magnetically isolated from female patients (n = 5), and IL24 expression was compared between these subsets. (3) Results: Females exhibited significantly higher expression of myofibroblast markers (MYH11, ET1, ENTPD2) and IL24 compared to males. IL24 expression positively correlated with pain severity in females, while no correlation was observed in males. Further exploration revealed that the myofibroblast fraction highly expressed IL24 compared to the fibroblast fraction in both male and female samples. There was no difference in the myofibroblast fraction between males and females. (4) Conclusions: Our study highlights the gender-specific role of myofibroblasts and IL24 in OA pathogenesis. Elevated IL24 levels in females, correlating with pain severity, suggest its involvement in OA pain experiences. The potential therapeutic implications of IL24, demonstrated in autoimmune disorders, open avenues for targeted interventions. Notwithstanding the limitations of the study, our findings contribute to understanding OA's multifaceted nature and advocate for future research exploring mechanistic underpinnings and clinical applications of IL24 in synovial myofibroblasts. Additionally, future research directions should focus on elucidating the precise mechanisms by which IL24 contributes to OA pathology and exploring its potential as a therapeutic target for personalized medicine approaches.

Low-Dose Irradiation and Rotating-Hinge Revision for the Treatment of Severe Idiopathic Arthrofibrosis Following Total Knee Arthroplasty: A Review of 60 Patients With a Mean 6-Year Follow-Up

BACKGROUND

Severe idiopathic arthrofibrosis after total knee arthroplasty (TKA) is a challenging problem to treat. Low-dose irradiation may decrease fibro-osseous proliferation, while rotating-hinge (RH) revision allows for distal femur shortening and collateral ligament sacrifice. This study reports the clinical outcomes and implant survivorship in patients treated with low-dose irradiation and RH revision for severe idiopathic arthrofibrosis following TKA.

METHODS

A retrospective review was performed on 60 consecutive patients. Patients who had greater than 80° arc of knee motion or less than 15° flexion contracture were excluded. Mean follow-up was 6 years (range, 2 to 14). Kaplan-Meier survivorship analyses were performed, and logistic regressions were used to determine associations between preoperative patient characteristics and clinical outcomes.

RESULTS

Median flexion contracture and median terminal flexion at presentation were 20 and 70°, respectively; at final follow-up, 59 of 60 patients (98%) had ≤10° flexion contracture and 49 of 60 patients (82%) had ≥90° of flexion. The 10-year survivorship free from reoperation for any reason, revision for any reason, and revision for aseptic loosening were 63, 87, and 97%, respectively. There were 27% percent of patients who underwent a manipulation under anesthesia postoperatively, which was the most common reason for return to the operating room. A greater number of prior surgeries was significantly associated with worse range of motion at the final follow-up (P = .004). There were no known radiation-associated complications.

CONCLUSIONS

Patients with severe idiopathic arthrofibrosis following TKA treated with low-dose irradiation and RH revision maintained a gain in knee range of motion of 60° with reliable flexion contracture correction at a mean 6-year follow-up. A manipulation under anesthesia was common in the postoperative period. Survivorship free from revision for aseptic loosening was excellent at 10 years.

No clinical advantage with customized individually made implants over conventional off-the-shelf implants in total knee arthroplasty: a systematic review and meta-analysis

INTRODUCTION

Total knee arthroplasty (TKA) can be performed with either conventional off-the-shelf (OTS) or customized individually-made (CIM) implants. The evidence for CIM implants is limited and variable, and the aim of this review was to compare clinical and radiological outcomes between CIM and OTS implants.

METHODS

A systematic review and meta-analysis were conducted in accordance with PRISMA guidelines. Studies reporting on clinical, radiological, or alignment outcomes for CIM and OTS implants were selected. The studies were appraised using the Methodical index for non-randomized studies tool.

RESULTS

Twenty-three studies fulfilled the inclusion criteria. The studies comprised 2856 CIM and 1877 OTS TKAs. Revision rate was higher with CIM (5.9%) compared to OTS (3.7%) implants [OR 1.23(95% CI 0.69-2.18)]. Manipulation under anesthesia (MUA) was higher in CIM (2.2%) compared to OTS (1.1%) group [OR 2.95(95% CI 0.95-9.13)] and complications rate was higher in CIM (5%) vs. OTS (4.5%) [OR 1.45(95% CI 0.53-3.96)] but neither reached statistical significance. Length of stay was significantly shorter in CIM group 2.9 days vs. 3.5 days [MD - 0.51(95% CI - 0.82 to - 0.20)]. Knee Society Score showed no difference between CIM and OTS groups for Knee 90.5 vs. 90.6 [MD - 0.27(95% CI - 4.27 to 3.73)] and Function 86.1 vs. 83.1 [MD 1.51(95% CI - 3.69 to 6.70)].

CONCLUSION

CIM implants in TKA have theoretical benefits over OTS prostheses. However, in this present review, CIM implants were associated with higher revisions, MUA, and overall complication rates. There was no difference in outcome score and CIM implants did not improve overall target alignment; however, more CIM TKAs were found to be in the HKA target zone compared to OTS TKAs. The findings of this review do not support the general utilization of CIM over OTS implants in TKA.

Modern robotics platform associated with reduced 90-day complications in hospital setting

BACKGROUND

Early complications in total knee arthroplasty (TKA) associated with modern robotics platforms integrated with digital balancing technology have not been investigated.

OBJECTIVE

The objective was to compare 90-day complication rates between a manual technique and a modern robotic-assisted ligament balancing TKA platform.

METHODS

895 primary TKA procedures from a single surgeon were retrospectively reviewed (614 manual TKA, 281 using a modern robotics platform with an integrated digitally controlled ligament balancing device). Post-operative complications within the 90-day episode of care were recorded by the Michigan Arthroplasty Registry Collaborative Quality Initiative. Differences in complication rates between techniques were further divided into inpatient hospital, outpatient hospital, and ambulatory surgery center (ASC) cohorts.

RESULTS

In the pooled hospital cohort and inpatient hospital cohort, 'Return to OR' was significantly lower for the robotic assisted group (1.3% vs 5.2% and 0% vs 4.9%, respectively, p< 0.0370). Specifically, the need for manipulation under anesthesia (MUA) was reduced for the robotics group (0.0% vs 2.5%, p= 0.0352). No differences in overall complication rate or cause of complication was found between manual and robotics cases for the hospital outpatient and ASC cohorts (p⩾ 0.68).

CONCLUSION

Within the hospital setting, robotic assisted ligament balancing technology was associated with reduced 90-day postoperative complications for 'Return to OR' and MUA.

Use of Botulinum Toxin A to Manage Hamstring-Induced Flexion Contracture Following Total Knee Arthroplasty: A Case Series

Introduction Flexion contractures following total knee arthroplasty (TKA) greatly affect patient function and satisfaction. Botulinum toxin A (BTX) has been described in the literature as a means of addressing post-operative flexion contractures due to hamstring muscle rigidity. Methods We retrospectively report a case series of eight patients with range of motion (ROM) who developed a flexion contracture status post-TKA and were managed with the use of physical therapy, diagnostic hamstring lidocaine injections, and therapeutic hamstring BTX injections. Results All patients had an improvement in extension ROM following diagnostic lidocaine hamstring injections and were therefore considered candidates for therapeutic hamstring BTX injections. Prior to therapeutic hamstring BTX injections, patients had an average flexion contracture of 19° (range: 15°-22°). All patients had an improvement in extension ROM two to four weeks following the therapeutic hamstring BTX injection, with an average improvement in ROM of 7° (range: 2°-19°). At the final follow-up, all patients continued to sustain an improvement in extension ROM with an average deficit of 9° (range: 0°-17°). Conclusion Our case series highlights the use of diagnostic hamstring lidocaine injections to confirm hamstring rigidity as an etiology for flexion contracture following TKA. In addition, we showed a persistent improvement in flexion contracture for all patients after hamstring BTX injections. Therefore, when the appropriate patient is selected, BTX may provide an additional treatment option for a flexion contracture following TKA.

Influence of Joint Line Level on Clinical Outcomes and Range of Motion in Total Ankle Arthroplasty

BACKGROUND

Ankle arthritis leads to an elevated joint line compared to the nonarthritic ankle, as measured by the "joint line height ratio" (JLHR). Previous work has shown that the JLHR may remain elevated after total ankle arthroplasty (TAA). However, the clinical impact of this has yet to be determined. This study assessed the correlation between postoperative JLHR, post-TAA range of motion (ROM), and 1-year Patient-Reported Outcome Measurement Information System (PROMIS) scores.

METHODS

A retrospective review of 150 patients who underwent primary TAA was performed. Preoperative and postoperative JLHR, as well as postoperative dorsiflexion, plantarflexion, and total ROM, was calculated on weightbearing radiographs at a minimum of 1-year follow-up. Correlation between JLHR, post-TAA ROM, and 1-year PROMIS scores was investigated using Pearson correlation and multiple linear regression models. Interobserver reliability for the JLHR was also calculated.

RESULTS

Interobserver reliability for the JLHR was excellent (r = 0.98). Mean (SD) JLHR changed from 1.66 (0.45) to 1.55 (0.26) after TAA (P < .001), indicating that the joint line was lowered after TAA. An elevated joint line was correlated with decreased post-TAA dorsiflexion (r = -0.26, P < .001), total ROM (r = -0.18, P = .025), and worse 1-year PROMIS physical function (r = -0.22, P = .046), pain intensity (r = 0.22, P = .042), and pain interference (r = 0.29, P = .007). There was no correlation between the JLHR and post-TAA plantarflexion (r = -0.025, P = .76). Regression analysis identified a 0.5-degree reduction in post-TAA dorsiflexion with each 0.1-unit increase in JLHR (Coeff. = -5.13, P = .005).

CONCLUSION

In this patient cohort, we found that an elevated joint line modestly correlated with decreased postoperative dorsiflexion, total ROM, and worse 1-year PROMIS scores. These data suggest that effort likely should be made toward restoring the native joint line at the time of TAA. In addition, future studies investigating the clinical outcomes after TAA may consider including a measure of joint line height, such as the JLHR, because we found it was associated with patient-reported outcomes.

LEVEL OF EVIDENCE

Level III, retrospective review of prospectively collected data.

The Effect of Tibiotalar Joint Line Level Alterations on Tibiotalar Range of Motion Following Total Ankle Arthroplasty

BACKGROUND

The effect of tibiotalar joint line level (TTJL) on patient outcomes following total ankle arthroplasty (TAA) remains unclear. It was previously reported that patients with end-stage ankle arthritis have an elevated TTJL compared with nonarthritic ankles, and the TTJL post-TAA remains elevated compared with nonarthritic ankles. The objectives of this study were to (1) propose a reliable radiographic method to measure the TTJL absolute value and (2) determine the effect of TTJL alterations on tibiotalar range of motion (ROM) following TAA.

METHODS

A retrospective review was performed on patients who underwent TAA between January 2018 and April 2021 with a minimum of 1-year postoperative follow-up and complete perioperative ROM radiographs. Radiographic TTJL and ROM measurements were performed by 2 observers. The proposed TTJL measuring technique computes 4 measurements: high, low, center of the talus (center), and center of the axis (axis). Reliability of measurements and correlation between TTJL measurements and ROM were assessed.

RESULTS

A total of 33 patients were included. Postoperatively, 22 patients had a lowered TTJL compared to 11 patients with an elevated TTJL (2.2 ± 1.3 mm lowered vs 1.9 ± 1.2 mm elevated; P < .0001). Of the 4 TTJL measurements, 3 (low, center, axis) demonstrated a significant positive correlation between lowering the TTJL and improved tibiotalar dorsiflexion and 2 (low, axis) for total ROM (all P < .05). Plantarflexion was not significantly affected by TTJL alterations. Compared to patients with an elevated TTJL, patients with a lowered TTJL had improved tibiotalar dorsiflexion (8.8 vs 2.5 degrees; P = .0015) and total ROM (31.0 vs 22.9 degrees; P = .0191), respectively. The interrater reliability was nearly perfect (intraclass correlation r = 0.96-0.99).

CONCLUSION

In this small series, we found that lowering the TTJL level may more closely reestablish the native TTJL and correlates with improved tibiotalar dorsiflexion and total ROM following TAA.

LEVEL OF EVIDENCE

Level IV, case series.

The effectiveness of cruciate-retaining versus posterior-stabilized designs on extensor mechanism function and knee function in patients after simultaneous bilateral total knee arthroplasty: A two-year retrospective follow-up study

INTRODUCTION

The importance of the posterior-cruciate ligament in knee functionality is known; however, the effect of preserving the posterior-cruciate ligament in total knee arthroplasty (TKA) on extensor mechanism function and knee function is not clear. We aimed to compare extensor mechanism function and knee function between patients operated with the cruciate-retaining and posterior-stabilized designs for simultaneous bilateral TKA.

HYPOTHESIS

Patients operated with the cruciate-retaining design would produce better outcomes than those operated with the posterior-stabilized design.

MATERIALS AND METHODS

A total of 104 patients were divided into two groups as the cruciate-retaining (n=52) and posterior-stabilized (n=52) groups. The groups were compared for extensor mechanism function (chair-rise test) and knee function (Hospital for Special Surgery [HSS] knee score). The follow-up points were six weeks, three months, six months, one year and two years.

RESULTS

No statistically significant effect on chair-rise performance of the group-by-time interaction (χ2 [5, n=104]=5.32, p=.37) or of group (χ2 [1, n=104]=1.69, p=.19). In the HSS knee score, the group-by-time interaction was statistically significant (F [5.510]=6.24, p<.001). A statistically significant difference of 7.4 points in favor of the posterior-stabilized group was found at six weeks (p=.002). No statistically significant differences were found between the groups at the other follow-up points.

DISCUSSION

The cruciate-retaining and posterior-stabilized designs have similar outcomes with regard to extensor mechanism function and knee function in the long-term period in patients who underwent simultaneous bilateral TKA. In the short-term period, the posterior-stabilized design shows better knee function than the cruciate-retaining design.

LEVEL OF EVIDENCE

III; a retrospective study.

Arthrofibrosis After Total Knee Arthroplasty: A Critical Analysis Review

» Arthrofibrosis after total knee arthroplasty (TKA) is the new formation of excessive scar tissue that results in limited ROM, pain, and functional deficits.» The diagnosis of arthrofibrosis is based on the patient's history, clinical examination, absence of alternative diagnoses from diagnostic testing, and operative findings. Imaging is helpful in ruling out specific causes of stiffness after TKA. A biopsy is not indicated, and no biomarkers of arthrofibrosis exist.» Arthrofibrosis pathophysiology is multifactorial and related to aberrant activation and proliferation of myofibroblasts that primarily deposit type I collagen in response to a proinflammatory environment. Transforming growth factor-beta signaling is the best established pathway involved in arthrofibrosis after TKA.» Management includes both nonoperative and operative modalities. Physical therapy is most used while revision arthroplasty is typically reserved as a last resort. Additional investigation into specific pathophysiologic mechanisms can better inform targeted therapeutics.

Arthroscopic Lysis of Adhesions for Arthrofibrosis After Anterior Cruciate Ligament Reconstruction

BACKGROUND

Arthrofibrosis (AF) after anterior cruciate ligament reconstruction (ACLR) remains a challenge. There is a paucity of data on arthroscopic interventions for AF after ACLR.

PURPOSE

To (1) describe the patient, injury, and surgical characteristics and patient-reported outcomes (PROs) of those requiring an arthroscopic intervention for loss of motion after ACLR and (2) compare outcomes between patients undergoing an early intervention (within 3 months) versus those undergoing a late intervention (after 3 months).

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Patients with a history of ACLR and a subsequent operative procedure for postoperative AF at a single institution between 2000 and 2018 were retrospectively identified. Arthroscopic interventions included lysis of adhesions, capsular release with or without manipulation under anesthesia, and excision of cyclops lesions. Patients were excluded if they had a knee dislocation or multiple-ligament injury, a periarticular fracture, or less than 2-year follow-up from the arthroscopic intervention. PROs including the Tegner activity score, visual analog scale pain score, and International Knee Documentation Committee score as well as knee range of motion (ROM) were recorded.

RESULTS

A total of 40 patients were included with a mean age of 27.2 years (range, 11.0-63.8 years) at surgery and a mean follow-up of 10.0 years (range, 2.9-20.7 years). The mean preoperative flexion and extension were 102° (range, 40°-150°) and 8° (range, 0°-25°), respectively. The mean postoperative flexion and extension were 131° (range, 110° to 150°) and 0° (range, -10° to 5°), respectively. After the arthroscopic intervention, the mean ROM improved from 94° (range, 40°-140°) preoperatively to 131° (range, 107°-152°) at final follow-up (P < .001), and the visual analog scale pain score improved from 3.0 preoperatively to 1.2 postoperatively (P = .001). Overall, 13 patients (32.5%) underwent an intervention within 3 months and 27 (67.5%) after 3 months. The early intervention group had a higher postoperative International Knee Documentation Committee score compared with the late intervention group (86.8 vs 71.7, respectively; P = .035).

CONCLUSION

An arthroscopic intervention for AF after ACLR successfully improved knee ROM and pain. Patients who underwent either early or late surgery obtained satisfactory motion and function, although improved PROs were observed when the intervention occurred within 3 months of the primary procedure.

Role of non-ASA VTE prophylaxis in risk for manipulation following primary total knee arthroplasty

INTRODUCTION

Stiffness and decreased range of motion frequently lead to hindrance of activities of daily living and dissatisfaction follow total knee arthroplasty (TKA). This study aims to evaluate the effect of non-aspirin (ASA) chemoprophylaxis and determine patient-related risk factors for stiffness and need for manipulation under anesthesia (MUA) following primary TKA.

MATERIALS AND METHODS

A review of all patients undergoing primary TKA from 2013 to 2019 at a single academic orthopedic hospital was conducted. The primary outcome measure was MUA performed post-operatively. Chi-square analysis and Mann-Whitney U test were used to determine statistically significant relationships between risk factors and outcomes. Significance was set at p < 0.05. Univariate logistic regression was performed to control for identified independent risk factors for MUA.

RESULTS

A total of 11,550 patients undergoing primary TKA from January 2013 to September 2019 at an academic medical center were included in the study. Increasing age and Charlson Comorbidity Index were associated with statistically significant decreased odds of MUA (0.93, 95% CI: 0.92-0.94, p < 0.001, OR 0.71, 95% CI 0.63-0.79, p < 0.001). Active smokers had a 2.01 increased odds of MUA (OR 2.01, 95% CI 1.28, 3.02, p < 0.001). There was no significant difference in rates of MUA between ASA and non-ASA VTE prophylaxis (p 0.108).

CONCLUSIONS

Younger age, lower CCI, and history of smoking are associated with a higher rate, while different chemical VTE prophylaxis does not influence rate of MUA after TKA. Arthroplasty surgeons should consider these risk factors when counseling patient preoperatively. Understanding each patients' risk for MUA allows surgeons to appropriately set preoperative expectations and reasonable outcome goals.

The Cost of Stiffness After Total Knee Arthroplasty

BACKGROUND

Stiffness after primary total knee arthroplasty (TKA) is debilitating and poorly understood. A heterogenous approach to the treatment is often utilized, including both nonoperative and operative treatment modalities. The purpose of this study was to examine the prevalence of treatments used between stiff and non-stiff TKA groups and their financial impact.

METHODS

An observational cohort study was conducted using a large database. A total of 12,942 patients who underwent unilateral primary TKA from January 1, 2017, to December 31, 2017, were included. Stiffness after TKA was defined as manipulation under anesthesia and a diagnosis code of stiffness or ankylosis, and subsequent diagnosis and procedure codes were used to identify the prevalence and financial impact of multiple common treatment options.

RESULTS

The prevalence of stiffness after TKA was 6.1%. Stiff patients were more likely to undergo physical therapy, medication, bracing, alternative treatment, clinic visits, and reoperation. Revision surgery was the most common reoperation in the stiff TKA group (7.6%). The incidence of both arthroscopy and revision surgery were higher in the stiff TKA population. Dual component revisions were costlier for patients who had stiff TKAs ($65,771 versus $48,287; P < .05). On average, patients who had stiffness after TKA endured costs from 1.5 to 7.5 times higher than the cost of their non-stiff counterparts during the 2 years following index TKA.

CONCLUSION

Patients who have stiffness after primary TKA face significantly higher treatment costs for both operative and nonoperative treatments than patients who do not have stiffness.

The Risk of Acute Infection Following Intra-Articular Corticosteroid Injection During Total Knee Manipulation Under Anesthesia

BACKGROUND

Manipulation under anesthesia (MUA) is an established option for improving motion in patients presenting with early stiffness following total knee arthroplasty (TKA). Intra-articular corticosteroid injections (IACI) are sometimes administered adjunctively, yet literature examining their efficacy and safety remains limited.

STUDY DESIGN

Retrospective, Level IV METHODS: A total of 209 patients (TKA = 230) were retrospectively examined to determine the incidence of prosthetic joint infections (PJI) within 3 months following manipulation with IACI. Approximately 4.9% of initial patients had inadequate follow-up where the presence of infection could not be determined. Range of motion (ROM) was assessed in patients who had follow-up at or beyond 1 year (n=158) and was recorded over multiple time points.

RESULTS

No infections (0 of 230) were identified within 90 days of receiving IACI during TKA MUA. Before receiving TKA (pre-index) patients averaged 111⁰ of total arc of motion (TAM) and 113⁰ of flexion. Following index procedures, just prior to manipulation (pre-MUA), patient's averaged 83⁰ and 86⁰ of total arc and flexion motion respectively. At final follow-up, patients averaged 110⁰ of TAM and 111⁰ of flexion. At 6 weeks following manipulation, patients had gained a mean of 25⁰ and 24⁰ of their total arc and flexion motion found at 1 year. This motion was preserved through a 12 month follow-up period.

CONCLUSION

Administering IACI during TKA MUA does not harbor an elevated risk for acute PJI. Additionally, its use is associated with substantial increases in short-term ROM at 6 weeks following manipulation, which remains preserved through long-term follow-up.

High Complication Rate Associated With Arthroscopic Lysis of Adhesions Versus Manipulation Under Anesthesia for Arthrofibrosis After Total Knee Arthroplasty

BACKGROUND

Arthrofibrosis after total knee arthroplasty (TKA) is often treated by arthroscopic lysis of adhesions (ALAs) or manipulation under anesthesia (MUA). This study compared the 2-year complication rates of ALA and MUA and range-of-motion (ROM) outcomes for ALA, early MUA (<3 months after TKA), and delayed MUA (>3 months after TKA).

METHODS

This retrospective cohort study included 425 patients undergoing ALA or MUA after primary TKA from 2001 to 2018. Demographics, clinical variables, and complication rates were collected from clinical records and compared using Student t -tests and Kaplan-Meier log-rank tests. Multivariable logistic regressions were used for adjusted analysis. ROM data were analyzed using fixed and mixed-effects models.

RESULTS

ALA patients were younger (55.2 versus 58.9 years, P < 0.001) and underwent surgery later from the index TKA (12 versus 1.9 months, P < 0.001). The Charlson Comorbidity Index was higher in the MUA group. Preoperative ROM was significantly worse in the MUA cohort, but did not differ between groups after the procedure (117°, P = 0.27) or at 2 years. Demographics and ROM outcomes were equivalent between early MUA and delayed MUA ( P = 0.75). The incidence of repeat arthrofibrosis (7.1%) and revision arthroplasty (2.4%) was similar between ALA and MUA cohorts while ALA patients had significantly more surgical site infections (3.8%) compared with MUA patients (0.47%, P = 0.017).

DISCUSSION

Equivalent ROM outcomes were seen between ALA, early MUA, and delayed MUA for the treatment of arthrofibrosis after TKA. However, this study demonstrated a markedly higher complication rate, particularly surgical site infection, after ALA, suggesting that MUA may be the preferred option for treating arthrofibrosis at both early and late time points.

A novel approach for joint line restoration in revision total ankle arthroplasty based on the three-dimensional registration of the contralateral tibia and fibula

PURPOSE

The use of total ankle arthroplasty (TAA) is increasing over time, as so will the need for revision TAAs in the future. Restoration of the ankle joint line (JL) in revision TAA is often difficult due to severe bone loss. This study analyzed the accuracy of a three-dimensional (3D) registration of the contralateral tibia and fibula to restore the ankle joint line (JL) and reported side-to-side differences of anatomical landmarks.

METHODS

3D triangular surface models of 96 paired lower legs underwent a surface registration algorithm for superimposition of the mirrored contralateral lower leg onto the original lower leg to approximate the original ankle JL using a proximal, middle and distal segment. Distances of the distal fibular tip, anterior and posterior medial colliculus to the JL were measured and absolute side-to-side differences reported. Anterior lateral distal tibial angle (ADTA) and lateral distal tibial angle (LDTA) were measured.

RESULTS

Mean JL approximation was most accurate for the distal segment (0.1 ± 1.4 mm (range: -3.4 to 2.8 mm)) and middle segment (0.1 ± 1.2 mm (range: -2.8 to 2.5 mm)) compared to the proximal segment (-0.2 ± 1.6 mm (range: -3.0 to 4.9 mm)) (p = 0.007). Distance of the distal fibular tip, the anterior, and posterior medial colliculus to the JL, ADTA and LDTA yielded no significant side-to-side differences (n.s.).

CONCLUSION

3D registration of the contralateral tibia and fibula reliably approximated the original ankle JL. The contralateral distal fibular tip, anterior and posterior medial colliculi, ADTA and LDTA can be used reliably for the planning of revision TAA with small side-to-side differences reported.

LEVEL OF EVIDENCE

IV.

Preoperative Virtual Total Knee Arthroplasty Surgery Using a Computed Tomography-based 3-dimensional Model With Variation in Reference Points and Target Alignment to Predict Femoral Component Sizing

Background

The purpose of this study was to investigate the size differences of 19 different femoral component placements from the standard position in total knee arthroplasty using 3-dimensional virtual surgery.

Methods

Three-dimensional bone models were reconstructed from the computed tomography data of 101 varus osteoarthritic knees. The distal femoral bone was cut perpendicular to the femoral mechanical axis (MA) in the coronal plane. Twenty different component placements consisting of 5 cutting directions (perpendicular to MA, 3° and 5° extension relative to MA [3°E-MA and 5°E-MA, respectively], and 3° and 5° flexion relative to MA [3°F-MA and 5°F-MA, respectively]) in the sagittal plane, 2 rotational alignments (clinical epicondylar axis [CEA] and surgical epicondylar axis [SEA]), and 2 rotational types of anterior reference guide (central [CR] and medial [MR]) were simulated.

Results

The mean anteroposterior dimension of femur ranged from 54.3 mm (5°F-MA, SEA, CR) to 62.5 mm (5°E-MA, CEA, MR). The largest and smallest differences of anteroposterior dimension from the standard position (3°F-MA, SEA, and CR) were 7.1 ± 1.3 mm (5°E-MA, CEA, and MR) and −1.2 ± 0.2 mm (5°F-MA, SEA, and CR), respectively. Multiple regression analysis revealed that flexion cutting direction, SEA, and CR were associated with smaller component size.

Conclusions

The femoral component size can be affected easily by not only cutting direction but also the reference guide type and the target alignment. Our findings could provide surgeons with clinically useful information to fine-tune for unintended loose or tight joint gaps by adjusting the component size.

Racial Differences in Manipulation Under Anesthesia Rates Following Total Knee Arthroplasty

BACKGROUND

Despite the extensive literature on racial disparities in care and outcomes after total knee arthroplasty (TKA), data on manipulation under anesthesia (MUA) is lacking. We aimed to determine (1) the relationship between race and rate of (and time to) MUA after TKA, and (2) annual trends in racial differences in MUA from 2013 to 2018.

METHODS

This retrospective cohort study (using 2013-2018 Medicare Limited Data Set claims data) included 836,054 primary TKA patients. The primary outcome was MUA <1 year after TKA; time from TKA to MUA in days was also recorded. A mixed-effects multivariable model measured the association between race (White, Black, Other) and odds of MUA. Odds ratios (OR) and 95% confidence intervals (CI) were reported. A Cochran Armitage Trend test was conducted to assess MUA trends over time, stratified by race.

RESULTS

MUA after TKA occurred in 1.7%, 3.2% and 2.1% of White, Black, and Other race categories, respectively (SMD = 0.07). After adjustment for covariates, (Black vs White) patients had increased odds of requiring an MUA after TKA: odds ratio (OR) 1.97, 95% confidence intervals (CI) 1.86-2.10, P < .0001. Moreover, White (compared to Black) patients had significantly shorter time to MUA after TKA: 60 days (interquartile range [IQR] 46-88) versus 64 days (interquartile range [IQR] 47-96); P < .0001. These disparities persisted from 2013 through 2018.

CONCLUSION

Continued racial differences exist for rates and timing of MUA following TKA signifying the continued need for efforts aimed toward understanding and eliminating inequalities that exist in total joint arthroplasty (TJA) care.

Cryoneurolysis Is a Safe, Effective Modality to Improve Rehabilitation after Total Knee Arthroplasty

Although long term pain and mobility outcomes in total knee arthroplasties (TKA) are successful, many patients experience significant amount of debilitating pain during the immediate post-operative period that necessitates narcotic use. Percutaneous cryoneurolysis to the infrapatellar saphenous and anterior femoral cutaneous nerves may help to better restore function and rehabilitation after surgery while limiting narcotic consumption. A retrospective chart review of primary TKA patients receiving pre-operative cryoneurolysis from 2019 to 2020 was performed to assess total opioid morphine milligram equivalents (MME) consumed inpatient and at interval follow-up. Demographics and medical comorbidities were compared between cryoneurolysis and age-matched control patients to assess baseline characteristics. Functional rehabilitation outcomes, including knee range of motion (ROM), ambulation distance, and Boston AM-PAC scores, as well as patient reported outcomes using the KOOS JR and SF-12 scores were analyzed using STATA 17 Software. The analysis included 29 cryoneurolysis and 28 age-matched control TKA patients. Baseline demographics and operative technique were not significant between groups. Although not statistically significant, cryoneurolysis patients had a shorter length of stay (2.5 vs. 3.5 days) and overall less inpatient and outpatient MME requirements. Cryoneurolysis patients had statistically significant improved 6-week ROM and 1-year follow-up KOOS JR and SF-12 mental scores compared to the control. There were no differences in complication rates. Cryoneurolysis is a safe, effective treatment modality to improve active functional recovery and patient satisfaction after TKA by reducing MME requirements. Patients who underwent cryoneurolysis had on average fewer MME prescribed during the perioperative period, improved active ROM, and improved patient-reported outcomes with no associated increased risk of infections, deep vein thrombosis, or neurologic complications.

Knee Arthrofibrosis following Tibial Plateau Fracture Treated with Arthroscopic Lysis of Adhesions with Manipulation

Posttraumatic arthrofibrosis is a common problem encountered in the orthopaedic setting for which there is no agreement on the optimal management strategy. The literature does not optimally describe the efficacy of arthroscopic lysis of adhesions for arthrofibrosis following tibial plateau fracture. The purpose of this study is to quantify the efficacy of arthroscopic lysis of adhesions with manipulation for the treatment of arthrofibrosis of the knee in patients who previously underwent surgical management of tibial plateau fracture. All patients who underwent arthroscopic lysis of adhesions from a single surgeon since 1999 were retrospectively reviewed. Clinical outcomes were evaluated by flexion, extension, and range of motion (ROM) preoperatively, intraoperatively, and postoperatively at intervals of 1, 4, 8, and 12 weeks, and any additional long-term follow-up. A total of 28 patients who had developed arthrofibrosis following surgical management of a tibial plateau fracture and failed nonsurgical management of knee stiffness were included in this study. There were significant improvements in total ROM following intervention at all time points compared with preoperative values (p < 0.001), with mean improvements of 59.3 degrees intraoperatively, 32.9 degrees (1 week), 37.1 degrees (4 weeks), 41.5 degrees (8 weeks), and 47.6 degrees (12 weeks). There were significant improvements in degrees of knee flexion following intervention at all time points compared with preoperative values (p < 0.001), with mean improvements of 50.8 degrees intraoperatively, 27.3 degrees (1 week), 36.0 degrees (4 weeks), 38.3 degrees (8 weeks), and 43.9 degrees (12 weeks). There were significant increases in degrees of knee extension intraoperatively (8.5 degrees) and at 1 week postoperatively (5.9 degrees) compared with preoperative values (p <0.01). At 12 weeks postoperatively, those who had previously undergone external fixation had significantly greater increases in ROM (p = 0.048). Arthroscopic lysis of adhesions for knee arthrofibrosis following surgical management of tibial plateau fracture significantly improves knee ROM.

Aspirin Administered for Venous Thromboembolism Prophylaxis May Protect Against Stiffness Following Total Knee Arthroplasty

BACKGROUND

Aspirin has become the main agent for venous thromboembolism (VTE) prophylaxis following total knee arthroplasty (TKA). This study assessed whether aspirin is associated with less knee stiffness compared to warfarin and other chemoprophylaxis agents.

METHODS

This is a retrospective review of all primary and revision TKAs performed between January 2009 and October 2020 at a high volume institution. Demographics, comorbidity data, and operative variables were extracted from medical records. VTE prophylaxis administered during this time period included aspirin, warfarin, and "others" (factor Xa, unfractionated heparin, low-molecular-weight heparin, fondaparinux, adenosine diphosphate receptor inhibitor, and direct thrombin inhibitor). The primary outcome assessed was manipulation under anesthesia (MUA) performed within 6 months of index surgery. Secondary outcome included major bleeding events. Univariate followed by multivariate regression analyses were performed.

RESULTS

A total of 15,903 cases were included in the study, of which 531 (3.3%) patients developed stiffness that required MUA. The rates of MUA were 2.7% (251/9223) for patients receiving aspirin, 4.2% (238/5709) for patients receiving warfarin, and 4.3% (42/971) for all others (P's < .001). Multivariate regression analysis confirmed that aspirin is associated with lower rates of VTE compared to warfarin (adjusted odds ratio 1.423, 95% confidence interval 1.158-1.747, P < .001) and compared to other anticoagulation medications (adjusted odds ratio 1.742, 95% confidence interval 1.122-2.704, P = .013). Major bleeding events were also significantly lower in patients who received aspirin compared to the other 2 groups (P's = .001).

CONCLUSION

Aspirin prophylaxis is associated with lower rates of MUA following TKA compared to warfarin and other VTE chemoprophylactic agents when grouped together.

Treatment of arthrofibrosis and stiffness after total knee arthroplasty: an updated review of the literature

PURPOSE

There is currently no consensus regarding the optimal treatment for stiffness following total knee arthroplasty (TKA). With the increased utilization of value-based models, it is important to determine the most effective treatments that will reduce the need for further intervention and additional expenditure. A systematic review was performed to compare the outcomes of manipulation under anaesthesia (MUA), arthroscopic lysis of adhesions (aLOA), and revision TKA (rTKA) for arthrofibrosis and stiffness following TKA.

METHODS

PubMed and MEDLINE databases were reviewed for articles published through October 2020. Studies were included if they reported patient-reported outcome measures (PROMs) following MUA, aLOA, or rTKA. The primary endpoint was PROMs, while secondary outcomes included range of motion and the percentage of patients who pursued further treatment for stiffness.

RESULTS

A total of 40 studies were included: 21 on rTKA, 7 on aLOA, and 14 on MUA. The mean or median post-operative arc ROM was > 90° in 6/20 (30%) rTKA, 5/7 (71%) aLOA, and 7/10 (70%) MUA studies. Post-operative Knee Society (KSS) clinical and functional scores were the greatest in patients who underwent MUA and aLOA. As many as 43% of rTKA patients required further care compared to 25% of aLOA and 17% of MUA patients.

CONCLUSION

Stiffness following TKA remains a challenging condition to treat. Nonetheless, current evidence suggests that patients who undergo rTKA have poorer clinical outcomes and a greater need for further treatment compared to patients who undergo MUA or aLOA.

E8002 Reduces Adhesion Formation and Improves Joint Mobility in a Rat Model of Knee Arthrofibrosis

Knee arthrofibrosis is a common complication of knee surgery, caused by excessive scar tissue, which results in functional disability. However, no curative treatment has been established. E8002 is an anti-adhesion material that contains L-ascorbic acid, an antioxidant. We aimed to evaluate the efficacy of E8002 for the prevention of knee arthrofibrosis in a rat model, comprising injury to the surface of the femur and quadriceps muscle 1 cm proximal to the patella. Sixteen male, 8-week-old Sprague Dawley rats were studied: in the Adhesion group, haemorrhagic injury was induced to the quadriceps and bone, and in the E8002 group, an adhesion-preventing film was implanted between the quadriceps and femur after injury. Six weeks following injury, the restriction of knee flexion owing to fibrotic scarring had not worsened in the E8002 group but had worsened in the Adhesion group. The area of fibrotic scarring was smaller in the E8002 group than in the Adhesion group (p < 0.05). In addition, the numbers of fibroblasts (p < 0.05) and myofibroblasts (p < 0.01) in the fibrotic scar were lower in the E8002 group. Thus, E8002 reduces myofibroblast proliferation and fibrotic scar formation and improves the range of motion of the joint in a model of knee injury.

Stiffness After Total Knee Arthroplasty: Prevalence and Treatment Outcome

Introduction

Stiffness following total knee arthroplasty (TKA) is an incapacitating complication. The prevalence and causes leading to stiffness are not clearly determined. The aim of the study was to ascertain the prevalence, determine the influencing factors, and evaluate the efficacy of manipulation under anaesthesia (MUA) as a treatment option.

Method

Retrospective review of consecutive series of 1350 primary TKA over a 28-month period. For the purpose of the study, stiffness was defined as flexion contracture of >15 degrees and/or flexion of <75 degrees. Demographic data included co-morbidities, previous knee surgery, pre-operative and post-operative range of movement, anaesthetic techniques and use of nerve blocks, type of prosthesis, ligament balancing including release, mobility post-surgery, patient motivation, physiotherapy, complications, and final range of motion post-MUA.

Results

Of the 1350 patients evaluated, 33 (2.44%) had stiffness defined by the above-outlined criteria and required intervention. Thirty-one patients (2.29%) underwent MUA as a first-line treatment. No complications arose following MUA. One patient (0.07%) required arthroscopic arthrolysis while another patient (0.07%) required revision arthroplasty due to patellar mal-tracking. Following manipulation, mean flexion contracture decreased from 8 degrees to 3.6 degrees, and mean flexion improved from 51.8 degrees to 93.2 degrees. Arc of motion improved in 100% of patients but it is important to note that multiple manipulations were performed in seven patients.

Conclusion

Stiffness after TKA can be difficult to treat and can result in prolonged morbidity and dissatisfaction. This retrospective study highlights the effectiveness of manipulation under anaesthesia as a first-line treatment option leading to improved outcomes especially if done early.

Rotating Hinge Revision Total Knee Arthroplasty for Severe Arthrofibrosis

Stiffness following total knee arthroplasty is a challenging complication for both the patient and surgeon, with an incidence that ranges from 1% to 13%1. There are several correctable mechanical causes for stiffness including malposition, malalignment, overstuffing, aseptic loosening, patella baja, and heterotopic ossification2. Idiopathic stiffness is often termed arthrofibrosis and is more difficult to treat1. Once patients have exhausted nonoperative options, including physical therapy and manipulation under anesthesia, revision surgery may be considered. Rotating hinge revision total knee arthroplasty has been shown to be an effective surgical treatment for severe arthrofibrosis.

Description

First, remove all soft-tissue and osseous sources of stiffness and adequately expose the knee, then remove all previous components. Create a stable and balanced extension gap, and, conversely, a relatively loose flexion gap, which allows for a substantial increase in range of motion. Then, in order to prevent instability in flexion, a rotating hinge prosthesis is utilized, which allows for appropriate kinematic motion despite gap imbalance. Additional steps to regain flexion include medial and lateral distal femoral partial condylectomies, as well as patellar component revision.

Alternatives

The first line of treatment for stiffness following total knee arthroplasty is nonoperative and is mainly focused on physical therapy3. Manipulation under anesthesia can also be performed within the first 12 weeks postoperatively3. Surgical treatments can include arthroscopic debridement as well as open debridement with possible polyethylene liner exchange. If there is a mechanical cause for stiffness, then this should also be addressed surgically. For cases of arthrofibrosis without a clear mechanical etiology or for cases in which the above treatment has failed, complete revision of the femoral and tibial components should be considered3. An alternative option to the technique proposed here is to utilize a varus-valgus constrained implant.

Rationale

Revision with a hinged implant allows for a more aggressive approach to regaining motion, as compared with all other surgical alternatives. By revising all components, the surgeon is able to remove all sources of stiffness and reconstruct the knee until as much range of motion as possible is achieved. Unfortunately, even with balanced extension and flexion gaps, refractory stiffness is common. A solution for this residual stiffness is to unbalance the gaps and create a loose flexion gap. By doing so, the surgeon is advised to switch to a hinged implant to create a kinematically balanced knee. Any other revision implant, such as a varus-valgus constrained implant, would risk flexion instability.

Expected Outcomes

Several studies have examined the use of revision total knee arthroplasty with a hinged implant for arthrofibrosis and have showed substantial improvements in knee range of motion. Bingham et al. showed that the rotating hinge group had a 20° improvement in range of motion (p = 0.048)1. Hermans et al. found a 35.8° flexion gain in the hinge group compared with a 14.2° flexion gain in the varus-valgus constrained group (p = 0.0002)4. van Rensch et al. found a median gain of 45° of range of motion5. Patients should be aware that this procedure involving the use of a hinged implant has similar risks to other revision total knee arthroplasty procedures; specifically, there is a risk of recurrent arthrofibrosis as well as mechanical complications1,5.

Important Tips

Achieve adequate exposure with a quadriceps snip.Perform a thorough synovectomy and debridement.Create a balanced extension gap with a relatively loose flexion gap.Distalize the joint line by resecting additional proximal tibia in cases of patella baja.Beware of refractory stiffness as a result of a scarred extensor mechanism.Consider revising the patellar component.Consider performing a partial condylectomy at the medial and lateral distal aspects of the femur.

Acronyms and Abbreviations

TKA = total knee arthroplastyAP = anteroposteriorCT = computed tomographyMRI = magnetic resonance imagingRHK = rotating hinge kneeNSAIDs = nonsteroidal anti-inflammatory drugs.

Heterotopic Ossification Negatively Influences Range of Motion After Revision Total Knee Arthroplasty

BACKGROUND

The incidence of heterotopic ossification (HO) after total knee arthroplasty (TKA) varies and is of unclear clinical significance. This study aimed to identify the incidence of HO in patients undergoing revision TKA for either stiffness or aseptic loosening/instability and determine if the presence of HO is associated with inferior absolute range of motion (ROM) and ROM gains.

METHODS

Eighty-seven patients were prospectively enrolled and separated into 2 cohorts to evaluate ROM after revision TKA (2017-2019). Group 1 (N = 40) patients were revised for stiffness, while group 2 (N = 47) patients were revised for either aseptic loosening or instability. Goniometer-measured ROM values were obtained preoperatively and at 6 weeks, 6 months, and 1 year postoperatively. Statistical analysis included a Fisher's exact test to assess for an association between preoperative HO and final ROM at 1 year after revision TKA.

RESULTS

HO was identified on preoperative radiographs in 17 patients (20%). There was a significantly higher rate of preoperative HO in patients revised for stiffness compared to patients revised for instability or loosening (30% vs 11%; P = .03). Five cases of HO qualitatively identified as most clinically severe were associated with lower ROM at each time point compared to the remainder of HO cases in this study cohort (P < .02).

CONCLUSION

The presence of HO is greater in patients undergoing revision TKA for stiffness. Additionally, HO severity appears to have a major effect on preoperative and postoperative ROM trajectory. This information should help guide patient expectations and highlight the need for a comprehensive, standardized classification system for HO.

Long-term Functional Results of Total Ankle Arthroplasty in Stiff Ankles

BACKGROUND

Total ankle arthroplasty (TAA) is advocated over ankle arthrodesis to preserve ankle motion (ROM). Clinical and gait analysis studies have shown significant improvement after TAA. The role and outcomes of TAA in stiff ankles, which have little motion to be preserved, has been the subject of limited investigation. This investigation evaluated the mid- to long-term functional outcomes of TAA in stiff ankles.

METHODS

A retrospective study of prospectively collected functional gait data in 33 TAA patients at a mean of 7.6 (5-13) years postoperatively used 1-way analysis of variance and multivariate regression analysis to compare among preoperative and postoperative demographic data (age, gender, body mass index, years postsurgery, and diagnosis) and gait parameters according to quartiles of preoperative sagittal ROM.

RESULTS

The stiffest ankles had a mean ROM of 7.8 degrees, compared to 14.3 degrees for the middle 2 quartiles, and 21.0 degrees for the most flexible ankles. Patients in the lowest quartile (Q1) also had statistically significantly lower step length, speed, max plantarflexion, and power preoperatively. Postoperatively, they increased step length, speed, max plantarflexion, and ankle power to levels comparable to patients with more flexible ankles preoperatively (Q2, Q3, and Q4). They had the greatest absolute and relative increases in these parameters of any group, but the final total ROM was still statistically significantly the lowest.

CONCLUSION

Preoperative ROM was predictive of overall postoperative gait function at an average of 7.6 (range 5-13) years. Although greater preoperative sagittal ROM predicted greater postoperative ROM, the stiffest ankles showed the greatest percentage increase in ROM. Patients with the stiffest ankles had the greatest absolute and relative improvements in objective function after TAA, as measured by multiple gait parameters. At intermediate- to long-term follow-up, patients with stiff ankles maintained significant functional improvements after TAA.

LEVEL OF EVIDENCE

Level III, comparative study.

Simulation of preoperative flexion contracture in a computational model of total knee arthroplasty: Development and evaluation

Preoperative flexion contracture is a risk factor for patient dissatisfaction following primary total knee arthroplasty (TKA). Previous studies utilizing surgical navigation technology and cadaveric models attempted to identify operative techniques to correct knees with flexion contracture and minimize undesirable outcomes such as knee instability. However, no consensus has emerged on a surgical strategy to treat this clinical condition. Therefore, the purpose of this study was to develop and evaluate a computational model of TKA with flexion contracture that can be used to devise surgical strategies that restore knee extension and to understand factors that cause negative outcomes. We developed six computational models of knees implanted with a posteriorly stabilized TKA using a measured resection technique. We incorporated tensions in the collateral ligaments representative of those achieved in TKA using reference data from a cadaveric experiment and determined tensions in the posterior capsule elements in knees with flexion contracture by simulating a passive extension exam. Subject-specific extension moments were calculated and used to evaluate the amount of knee extension that would be restored after incrementally resecting the distal femur. Model predictions of the extension angle after resecting the distal femur by 2 and 4 mm were within 1.2° (p ≥ 0.32) and 1.6° (p ≥ 0.25), respectively, of previous studies. Accordingly, the presented computational method could be a credible surrogate to study the mechanical impact of flexion contracture in TKA and to evaluate its surgical treatment.

Home physiotherapy with vs. without supervision of physiotherapist for assessing manipulation under anaesthesia after total knee arthroplasty

Abstract

The aim of this retrospective cohort study was to compare home physiotherapy with or without supervision of physiotherapist for assessing manipulation under anaesthesia after total knee arthroplasty.

Methods

A total of 900 patients (including 810 females and 90 males) who had undergone total knee arthroplasty were divided into group A (n = 300) and group B (n = 600). Patients in group A had home physiotherapy on their own after discharge from hospital. The physiotherapist did not visit them at home. Patients in group B received home physiotherapy under supervision of physiotherapist for 6 weeks after discharge from hospital. Patients’ age, range of motion of the knee, and forgotten joint score-12 were assessed. A p < 0.05 was considered statistically significant.

Results

In group A, the mean age was 69.1 ± 14.3 years (range: 58 to 82 years); in group B, the mean age was 66.5 ± 15.7 years (range: 56 to 83 years) (p > 0.05). Preoperatively, the mean range of motion of the knee in group A and B was 95.8° ± 18.1° and 95.4° ± 17.8°, respectively (p > 0.05). The mean forgotten joint score-12 of group A and B were 11.90 ± 11.3 and 11.72 ± 12.1 (p > 0.05), respectively. Six weeks after total knee arthroplasty, the mean ROM of the knee in group A and B was 109.7° ± 22.3° and 121° ± 21.5°, respectively (p < 0.05). The mean postoperative forgotten joint score-12 of the group A and B was 24.5 ± 16.4 and 25.6 ± 17.4, respectively (p > 0.05). The rate of manipulation under anaesthesia was 3% in group A and 0.2% in group B (p < 0.05).

Conclusion

After total knee arthroplasty, frequent physiotherapist’s instruction helps the patients improve knee exercises and therefore decrease the risk of revision surgery. The home physiotherapy under supervision of physiotherapist lowers the rate of manipulation under anaesthesia.

Level of evidence

Therapeutic study, Level IIa.

Patients with Dupuytren's Contracture, Ledderhose Disease, and Peyronie's Disease are at higher risk of arthrofibrosis following total knee arthroplasty

BACKGROUND

Total knee arthroplasty (TKA) is a successful treatment for patients with late stage osteoarthritis, yet arthrofibrosis remains a consistent cause of TKA failure. Dupuytren's, Ledderhose and Peyronie's Diseases are related conditions of increased fibroblast proliferation. The aim of this study was to identify whether an association exists between these conditions and arthrofibrosis following TKA.

METHODS

Patient records were queried from 2010 to 2016 using an administrative claims database to compare the rates of arthrofibrosis, manipulation under anesthesia (MUA), lysis of adhesions (LOA), and revision TKA in patients with independent chart diagnoses of Dupuytren's Contracture, Ledderhose, or Peyronie's Diseases versus those without. Complications were queried and compared using multivariate logistic regression.

RESULTS

Patients with Dupuytren's (n = 5,232) and Ledderhose (n = 50,716) had a significantly higher rate of ankylosis following TKA: 30-days (OR, 1.54; OR, 1.23), 90-days (OR, 1.20; OR, 1.24), 6-months (OR, 1.23; OR, 1.23), and 1-year (OR, 1.28; OR, 1.23), while patients with Peyronie's (n = 1,186) had a higher rate of diagnosis at 6-months (OR, 1.37) and 1-year (OR, 1.35). Patients with diagnoses of any of the fibroproliferative diseases had a statistically higher risk of MUA at 90-days, 6-month, and 1-year following primary TKA. These cohorts did not have a significantly higher rate of revision TKA.

CONCLUSION

There is an increased odds risk of arthrofibrosis and MUA in patients who have undergone TKA and have a diagnosis of Dupuytren's Contracture, Ledderhose, or Peyronie's Diseases. Improvements to frequency and application of post-operative treatment should be considered in these cohorts to improve outcomes.

Association Between Femoral "Spike" Size After Intramedullary Nailing and Subsequent Knee Motion Surgery

OBJECTIVES

To determine the association between displaced femoral shaft bone fragments ("spikes") seen on radiographs after intramedullary nail insertion and the need for future motion surgery.

DESIGN

Retrospective case-control study.

SETTING

Academic trauma center.

PATIENTS

We included patients with femoral shaft fractures treated with intramedullary nail insertion. Case patients (n = 22) had developed knee stiffness treated with motion surgery. The control group was a randomly selected sample (1:3 ratio).

MAIN OUTCOME MEASURES

Motion surgery to address knee stiffness. We defined a "spike distance ratio" and "spike area ratio" from initial postoperative anteroposterior and lateral radiographs. Multivariable logistic regression determined the effect of spike distance and area ratios on the likelihood of need for motion surgery, controlling for polytraumatic injuries and bilateral fractures.

RESULTS

The case group had a median femoral spike distance ratio of 1.9 [interquartile range (IQR), 1.6-2.5] compared with 1.5 (IQR, 1.2-1.8) in the control group. An increased femoral spike distance ratio was associated with increased odds of motion surgery (P < 0.01). A femoral spike distance >2 times the femoral radius had 32 times the odds (95% confidence interval, 2-752) of motion surgery compared with patients with distance ratios <1.25. Median femoral spike area ratios were similar between the case (0.2; IQR, 0.1-0.5) and control (0.2; IQR, 0.0-0.5) groups and were not associated with increased odds of motion surgery (P = 0.34).

CONCLUSIONS

A larger spike distance ratio is associated with increased odds of subsequent motion surgery.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Range of Motion at Discharge Predicts Need for Manipulation following Total Knee Arthroplasty

Stiffness following total knee arthroplasty (TKA) is a common complication that can result in unsatisfactory outcomes. Manipulation under anesthesia (MUA) has been widely employed to treat this problem. It is uncertain whether an association exists between range of motion (ROM) at discharge and need for MUA following primary TKA.A retrospective review of an institutional joint registry identified cases of primary TKA performed by three surgeons at a single institution over a 22-month period. A logistic regression model was used to examine the association between ROM at discharge and subsequent MUA controlling for confounding variables related to patient demographics and perioperative details. Of the 1,546 cases identified, 113 (7.3%) cases underwent subsequent MUA. As discharge ROM increased, manipulation rates decreased. Patients with discharge flexion <65 degrees were more likely to undergo MUA than those with flexion >90 degrees (odds ratio [OR] = 17.57, 95% confidence interval [CI] [7.97, 38.73], p < 0.0001). The largest differential in odds of MUA was observed between the <65 degrees at discharge group (OR = 17.57) and the 65 ≤ 75 degrees at discharge group (OR = 7.89). At discharge ROM of 80 ≤ 90 degrees of flexion, patients had more than a twofold increase in odds of MUA relative to those in the >90 degrees group (OR = 2.22, 95% CI [1.20, 4.10], p = 0.011). The results of this study suggest that there is an association between lower ROM at discharge and greater risk of MUA post primary TKA. Counseling patients in regard to discharge ROM and associated risk of MUA may optimize gains in ROM during recovery.

Kinematic versus mechanically aligned total knee arthroplasty: no difference in frequency of arthroscopic lysis of adhesions for arthrofibrosis

Arthrofibrosis is a condition that can cause excessive scar tissue formation, leading to painful restriction of joint motion. Following total knee arthroplasty (TKA), significant arthrofibrosis can result in permanent deficits in range of motion (ROM) if not treated. Although arthroscopic lysis of adhesions (ALOA) reliably improves post-TKA ROM if performed in a timely fashion, it exposes patients to additional anesthesia, heightens the risk of infection, and increases overall medical expenses. Kinematically aligned TKA has emerged as an alternative method to mechanically aligned, basing bony cuts off of the patient's pre-arthritic anatomy while limiting need for soft tissue and ligamentous releases. This study aimed to determine whether there is a difference in the frequency of post-TKA arthrofibrosis requiring ALOA between kinematic and mechanically aligned TKA. Between 2012 and 2019, a retrospective analysis was conducted based on a single surgeon's experience. Two cohorts were made based on alignment technique. Postoperatively, patients were diagnosed with arthrofibrosis and indicated for ALOA if they had functional pain with < 90 degrees of terminal flexion at 6 weeks postoperatively despite aggressive physical therapy. Frequency of ALOA was recorded for each cohort and was regressed using independent samples t-test. The results showed no significant difference between the mechanical and kinematic cohorts for frequency of ALOA following TKA (13.2% vs. 7.3%; p = 0.2659). However, the kinematic cohort demonstrated significantly greater post-ALOA ROM compared to the mechanical group (129° vs. 113°; p = 0.0097). Future higher-powered, prospective studies are needed to clarify whether a significant difference in rates of MUA/ALOA exists between the two alignment techniques.

Prior Manipulation under Anesthesia is a Predictor of Contralateral Manipulation in Staged Bilateral Total Knee Arthroplasty

BACKGROUND

There are many risk factors for arthrofibrosis and manipulation under anesthesia (MUA) following total knee arthroplasty (TKA). However, no study has elucidated whether a history of MUA increases the risk of contralateral MUA in patients undergoing staged bilateral TKA.

METHODS

A retrospective review of an institutional database of TKAs was performed. All patients aged ≥18 years who underwent primary staged bilateral TKAs were screened for inclusion. Staged bilateral TKAs were viewed as 2 distinct events based on the temporal order in which they occurred: TKA#1 (occurred first) and TKA#2 (occurred second). Following TKA#1, patients were split into 2 groups: those who underwent MUA (Group MANIP) and those who did not (Group NO MANIP). The subsequent risk of undergoing MUA following TKA#2 was then assessed and compared between the 2 groups. Chi-squared tests were used for comparison.

RESULTS

A total of 5,330 patients who underwent primary uncomplicated staged bilateral TKAs (10,660 knees) during the study period were identified. Overall, 2.1% of patients underwent MUA following TKA#1 and 1.9% of patients underwent MUA following TKA#2. In the MANIP group, 21.4% of patients underwent MUA following TKA#2, while only 1.5% underwent MUA in the NO MANIP group. This 14.3-fold increase in the risk of MUA in the MANIP group following TKA#2 was statistically significant (21.4% vs 1.5%, absolute risk reduction = 19.9%, relative risk reduction = 93.0%, P < .0001).

CONCLUSION

Patients who undergo MUA during the first TKA of a staged bilateral TKA are 14.3 times more likely to undergo a subsequent MUA than those who did not undergo MUA following their first TKA.

Can adjunctive perioperative radiation improve range of motion after total knee revision for arthrofibrosis?

BACKGROUND

Total knee arthroplasty revision (TKRev) can be performed to treat chronic arthrofibrosis. Low-dose irradiation may decrease fibro-osseous proliferation of soft tissue; therefore, it may be effective at increasing range of motion (ROM) after TKRev. Our hypothesis is that low-dose radiation administered in the immediate postoperative period leads to increased ROM after TKRev for arthrofibrosis.

METHODS

A retrospective analysis was conducted from 2008-2015 on 26 patients who underwent TKRev for treating chronic arthrofibrosis. Fifteen patients (XRT group) received 800 cGy radiation within 48 hours after TKRev and 11 patients (CTL group) did not. Measurements of extension, flexion, and total arc of ROM were performed preoperatively and at one, six, and 12 months postoperatively.

RESULTS

ROM improved from 14.3° extension, 69.0° flexion, and 54.7° total ROM preoperatively, to 3.3° extension, 94.0° flexion, and 90.7° total ROM postoperatively in the XRT group. ROM improved from 18.6° extension, 85.9° flexion, and 67.3° total ROM preoperatively to 4.1° extension, 102.5° flexion, and 98.5° total ROM postoperatively in the CTL group. The 1-year overall improvement in extension (12.5°), flexion (21.4°), and total ROM (33.9°) vs preoperative ROM was significant for all measurements (p < 0.001). The 8.4° improvement in flexion (25.0° vs 16.6°, p = 0.10) in the XRT group vs the CTL group approached, but did not reach significance.

CONCLUSIONS

TKRev for arthrofibrosis showed significant improvement in extension, flexion, and total ROM at one year. The use of low dose irradiation showed promise with improved flexion, but the result did not reach statistical significance in this small sample of patients.

Arthrofibrosis of the Ankle

Arthrofibrosis is a common, but often overlooked, condition that imparts significant morbidity following injuries and surgery to the foot and ankle. The most common etiologies are related to soft tissue trauma with subsequent fibrotic and contractile scar tissue formation within the ligaments and capsule of the ankle. This leads to pain, alterations in gait, and ankle dysfunction. Initial treatment often includes extensive physical therapy, however, if severe enough surgical options exist. Although the literature regarding ankle arthrofibrosis is scarce, this review article provides a greater understanding of the pathogenesis of arthrofibrosis and describes the current and future therapeutic options to treat fibrotic joints. Level of Evidence: Level V, expert opinion.

Arthroscopic Lysis of Adhesions With Manipulation for Management of Late-Presenting Stiffness After Total Knee Arthroplasty

Background

Arthrofibrosis is a known complication of total knee arthroplasty (TKA). Closed manipulation is the treatment of choice for arthrofibrosis within 90 days of TKA. Treatment for arthrofibrosis that has failed prior interventions remains controversial, and the role for arthroscopic lysis of adhesions has not been examined for late-presenting arthrofibrosis.

Methods

A retrospective analysis of patients who underwent arthroscopic lysis of adhesions (LOAs) with manipulation for post-TKA arthrofibrosis was performed. Chart review included patient characteristics, time from TKA, prior interventions, and range of motion (ROM) data. Knee extension, flexion, and total ROM were recorded preoperatively, intraoperatively, and throughout follow-up. Knee ROM was compared at the different time intervals using Wilcoxon signed-rank tests.

Results

A total of 13 patients (6 male and 7 female) with a mean age of 66.3 years were included. Average time since index TKA was 57.2 months (3.7-209.5). Ten of 13 patients had undergone prior interventions for arthrofibrosis, which included closed manipulation under anesthesia, open LOA, and revision arthroplasty. The mean preoperative knee flexion and extension values for the cohort were 76.5 ± 17.4 and −4.6 ± 6.1 degrees, respectively. Postoperative improvements in knee ROM were significant at all time points, with mean improvements of 17.2 ± 16.3 degrees at 1 week (P = .022), 17.2 ± 13.2 degrees at 4 weeks (P = .001), 19.2 ± 16.0 degrees at 8 weeks (P = .004), and 25.2 ± 13.1 degrees at 12 weeks (P = .005). No complications were recorded.

Conclusions

Arthroscopic LOAs with manipulation achieves significant improvements in knee ROM for late-presenting arthrofibrosis after TKA.

Current state of total knee arthroplasty

Total knee arthroplasty (TKA) is a successful and cost-effective treatment for end-stage degenerative arthritis. The aging of society and an increase in the prevalence of obesity has led to increases in the prevalence of arthritis and the incidence of TKA. Currently, the total number of procedures in Korea per year has reached 90,000. With the rapid growth, we need to know about the current state of TKA. The purpose of this review is to summarize the recent literature regarding TKA. The main indication for TKA is end-stage arthritis with severe pain, reduced function, and no response to conservative management. Metal on the polyethylene-bearing surface and cobalt alloy are used in most TKAs. Despite good clinical outcomes and long-term survival rates after TKA in many papers, 20% of patients are dissatisfied with the outcome of surgery. To improve the patient’s satisfaction, surgeons should understand factors affecting patient’s satisfaction, including patient’s expectations, age, and preoperative mental state. Navigation-assisted surgery and robotic surgery have been introduced in knee arthroplasty to achieve more precise and accurate alignment. There is some evidence to suggest that computer-assisted surgery reduces revision rates. However, clinical efficacy is also controversial, and a long-term follow-up study is required. The common complications of TKA include infection, polyethylene wear, loosening, stiffness, periprosthetic fracture, and thromboembolism. An understanding of the potential complications and pitfalls of TKA is essential for prevention.