Clinical, objective, and functional outcomes of manipulation under anesthesia to treat knee stiffness following total knee arthroplasty

Evaluation of painful total knee arthroplasty: an approach based on common etiologies for total knee arthroplasty revision

A differential diagnosis with emphasis on the common indications for revision should be utilized in the workup of painful total knee arthroplasty (TKA). The physician should identify the exact etiology of the patient's pain to maximize outcomes from treatment. Evaluation for infection should be completed using the Musculoskeletal Infection Society (MSIS) criteria. When common causes of revision TKA do not appear to be the cause of the pain, less likely causes should be not be ignored. Further advancements such as pressure sensing devices may be able to improve patient satisfaction and decrease the incidence of pain following TKA.

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.

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.

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.

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.

Manipulation Under Anesthesia Is Associated With an Increased Rate of Early Total Knee Arthroplasty Revision

Manipulation under anesthesia (MUA) after total knee arthroplasty (TKA) frequently has been used as a first-line treatment to restore functional range of motion after unsuccessful physical therapy. Although there are studies reporting that MUA assisted in restoring range of motion, there is a paucity of literature on the influence of MUA on the risk of revision TKA. The goal of our study was to determine whether MUA was associated with an increase in the rate of revision TKA within 2 years of MUA. A total of 49,310 patients within a single institution who underwent primary TKA were identified from 1999 to 2019. Data were matched at a 1:3 ratio (TKA with and without MUA, respectively) based on age, sex, and body mass index. A matched comparison cohort was conducted, with the MUA cohort having 575 patients and the no MUA cohort having 1725 patients. A statistically significant increase in the rate of noninfectious etiology revision TKA was found in the MUA cohort (7.3%) compared with the no MUA cohort (4.9%; P=.034). The most common reason for revision TKA after MUA was persistent stiffness, including arthrofibrosis and ankylosis; however, aseptic loosening, ligamentous instability, and periprosthetic fracture were found to be responsible for 21.4% of revision TKA procedures. Although MUA is a commonly performed procedure for treating stiffness after primary TKA, the orthopedic surgeon should counsel patients on the association of increased rate of revision TKA after MUA, most commonly, persistent stiffness. [Orthopedics. 2022;45(5):270-275.].

Predictive Gap-balancing Reduces the Extent of Soft-tissue Adjustment Required After Bony Resection in Robot-assisted Total Knee Arthroplasty-A Comparison With Simulated Measured Resection

Background

To understand the extent and frequency of soft-tissue adjustment required to achieve mediolateral (ML) balance in measured resection (MR) vs gap-balancing (GB) total knee arthroplasty, this study compared ML balance and joint laxity throughout flexion between the 2 techniques. The precision of predictive GB in achieving ML balance and laxity was also assessed.

Methods

Two surgeons performed 95 robot-assisted GB total knee arthroplasties with predictive balancing, limiting tibial varus to 3° and adjusting femoral positioning to optimize balance. A robotic ligament tensioner measured joint laxity. Planned MR (pMR) was simulated by applying neutral tibial and femoral coronal resections and 3° of external femoral rotation. ML balance, laxity, component alignment, and resection depths were compared between planned GB (pGB) and pMR. ML balance and laxity were compared between pGB and final GB (fGB).

Results

The proportion of knees with >2 mm of ML imbalance in flexion or extension ranged from 3% to 18% for pGB vs 50% to 53% for pMR (P < .001). Rates of ML imbalance >3 mm ranged from 0% to 9% for pGB and 30% to 38% for MR (P < .001). The mean pMR laxity was 1.9 mm tighter medially and 1.1 mm tighter laterally than pGB throughout flexion. The mean fGB laxity was greater than the mean pGB laxity by 0.5 mm medially and 1.2 mm laterally (P < .001).

Conclusion

MR led to tighter joints than GB, with ML gap imbalances >3 mm in 30% of knees. GB planning improved ML balance throughout flexion but increased femoral posterior rotation variability and bone resection compared to MR. fGB laxity was likely not clinically significantly different than pGB.

Perioperative Use of Antifibrotic Medications Associated With Lower Rate of Manipulation After Primary TKA: An Analysis of 101,366 Patients

BACKGROUND

Several commonly prescribed medications have known antifibrotic properties and have been shown to reduce postoperative scar formation in other clinical areas, but it is unknown whether the use of such medications perioperatively in patients undergoing TKA may improve rates of postoperative stiffness.

METHODS

A large US employer-sponsored healthcare database (Truven Marketscan) was queried for patients who underwent elective primary TKA for primary osteoarthritis between 2015-2019. Demographic information and comorbidities were recorded, along with whether patients were prescribed one of several medications with known antifibrotic properties during the three months before or after surgery.

RESULTS

Complete data were available for 101,366 patients undergoing TKA, of which 4,536 underwent MUA (4.5%). Perioperative use of any antifibrotic medication was associated with a lower likelihood of undergoing MUA (P < .001). When controlling for age, sex, comorbidities, opioid use, length of stay, among other variables, perioperative use of specific ACE inhibitors (OR 0.91, CI 0.84-1, P = .042), COX-2 inhibitors (OR 0.88, CI 0.81-0.96, P = .002), and angiotensin II receptor blockers, specifically losartan (OR 0.80, CI 0.70-0.91, P = .007) all remained significantly associated with lower rates of MUA.

CONCLUSION

This study, spanning over a hundred thousand primary TKA procedures over a recent five-year period, demonstrates an association between perioperative use of specific medications with antifibrotic properties and a decreased rate of MUA. These data will help inform future studies aimed to prospectively evaluate the potential of antifibrotic medications in preventing postoperative stiffness in high-risk patients undergoing knee arthroplasty.

Efficacy of non-operative treatment of patients with knee arthrofibrosis using high-intensity home mechanical therapy: a retrospective review of 11,000+ patients

Background

Recovery from knee surgery or injury can be hindered by knee arthrofibrosis, which can lead to motion limitations, pain and delayed recovery. Surgery or prolonged physical therapy are often treatment options for arthrofibrosis, but they can result in increased costs and decreased quality of life. A treatment option that can regain lost motion without surgery would help minimize risks and costs for the patient. The purpose of this study was to determine treatment efficacy of high-intensity home mechanical stretch therapy in patients with knee arthrofibrosis.

Methods

Records were reviewed for 11,000+ patients who were prescribed a high-intensity stretch device to regain knee flexion. Initial and last recorded knee flexion and days between measurements were available for 9842 patients (Dataset 1). Dataset 2 was a subset of 966 patients from Dataset 1. These 966 patients had separate more rigorous measurements available from physical therapy notes (Dataset 3) in addition to data from the internal database (Dataset 2). Within and between dataset statistics were calculated using t tests for comparison of means and Cohen’s d for determination of effect size.

Results

All dataset showed significant gains in flexion (p < 0.01). Mean initial flexion, last recorded flexion and flexion gain were 79.5°, 108.4°, and 29.9°, respectively in Dataset 1. Differences between Datasets 2 and 3 had small effect sizes (Cohen’s d < 0.17). The were no significant differences when comparing workers’ compensation and non-workers’ compensation patients. The average last recorded flexion for all datasets was above the level required to perform activities of daily living. Motion gains were recorded in under 60 days from device delivery.

Conclusions

High-intensity home mechanical stretch therapy was effective in restoring knee flexion, generally in 2 months or less, and in avoiding additional surgery in severe motion loss patients regardless of sex, age, or workers’ compensation status. We believe high-intensity stretching should be considered in any patient who is at risk for a secondary motion loss surgery, because in over 90% of these patients, the complications and costs associated with surgery can be avoided.

Early Identification of Arthrofibrosis in Adolescents Following Anterior Cruciate Ligament Reconstruction Is Associated With the Need for Subsequent Surgery: A Matched Case-Control Study

PURPOSE

To identify the postoperative characteristics associated with the need for subsequent surgical intervention in pediatric anterior cruciate ligament reconstruction (ACLR).

METHODS

Patients ≤18 years old who received operative treatment for arthrofibrosis following ACLR versus age- and sex-matched controls with a satisfactory postoperative course were retrospectively reviewed. The range of knee motion preoperatively and at each postoperative visit was recorded. Based on the typical post-operative protocols, visits were categorized into 3 groups: first (first 4 weeks), second (weeks 5-8), and third (weeks 9-16) visits. The deficit in the total arc of range of motion (ROM) in the operative knee relative to the nonoperative knee and the change in ROM between visits were compared. Receiver operating characteristic analysis was performed to determine the time point in which a diagnosis of arthrofibrosis could be predicted with the greatest accuracy.

RESULTS

In total, 18 patients with arthrofibrosis (mean age 14.2 ± 2.7 years, 9 male) and 36 control patients were included in the final analysis. Arthrofibrosis patients had significantly larger ROM deficits at all visits, 93° vs 69° for the first, 69° vs 24° for the second, and 56° vs 2º for the third, compared with controls (P < .001 for all). Pairwise comparisons showed that in arthrofibrosis cases, the total ROM did not change significantly between the second and third visits (P = .77), contrary to the controls. Receiver operating characteristic analysis revealed that the total ROM deficit of 50.7° at the second postoperative visit is 89% sensitive and 92.5% specific for development of arthrofibrosis.

CONCLUSIONS

We found that patients who go on to need manipulation of the knee under anesthesia/arthroscopic lysis of adhesions do not experience a significant improvement in ROM after the first 5-8 weeks, and that a ROM deficit of >50° at the 5- to 8-week mark postoperatively, is associated with ultimately needing operative intervention for arthrofibrosis. Based on these findings, it may be appropriate to intervene earlier if a patient still has a ROM deficit exceeding 50° by the second postoperative month.

LEVEL OF EVIDENCE

Level III, retrospective comparative prognostic trial.

Manipulation under anesthesia after total knee arthroplasty: a retrospective study of 145 patients

BACKGROUND AND PURPOSE

Manipulation under anesthesia (MUA) is considered to be effective in treating stiffness after total knee arthroplasty (TKA). However, not all patients achieve a satisfactory range of motion (ROM) after MUA. This retrospective study determined the outcome of MUA and identified the factors affecting it.

PATIENTS AND METHODS

The final sample consisted of 150 MUAs performed on 145 patients. The parameters of interest were ROM and Knee Society Score (KSS) or Oxford Knee Score (OKS). The associations of preoperative, perioperative, and postoperative risk factors with gain in flexion and flexion at post-MUA follow-up (an average of 2 months after MUA) were analyzed using multivariable regression model.

RESULTS

The mean of 26° (95% CI 23-29) gain in flexion and the mean of 3° (CI 2-4) gain in extension were noticed at post-MUA follow-up when compared with the ROM preceding MUA. The mean post-MUA-FU flexion was 99° (CI 97-102) and the mean post-MUA-FU extension deficit was 4° (CI 2-5). KSS (121 vs. 129) and OKS (29 vs. 28) were similar before and after MUA. The early timing of MUA was associated with better gain in flexion -0.04 (CI -0.08 to -0.01), while we found no association between the timing of MUA and flexion after MUA -0.004 (CI -0.03 to 0.03). High BMI was associated with better gain in flexion 0.8 (CI 0.2-1.5).

INTERPRETATION

We found that ROM improved substantially after MUA. The gain in flexion decreased as the time between TKA and MUA increased.

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.

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.

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.

Pigmented villonodular synovitis does not influence the outcomes following cruciate-retaining total knee arthroplasty: a case-control study with minimum 5-year follow-up

BACKGROUND

Pigmented villonodular synovitis (PVNS) is a rare synovial disease with benign hyperplasia, which has been successfully treated with total knee arthroplasty (TKA). The purpose of this study was to investigate the middle-term follow-up outcomes of cruciate-retaining (CR) TKA in patients with PVNS.

METHODS

From January 2012 to December 2014, a retrospective study was conducted in 17 patients with PVNS who underwent CR TKA as PVNS group. During this period, we also selected 68 patients with osteoarthritis who underwent CR TKA (control group) for comparison. The two groups matched in a 1:4 ratio based on age, sex, body mass index, and follow-up time. The range of motion, Knee Society Score, revision rate, disease recurrence, wound complications, and the survivorship curve of Kaplan-Meier implant were assessed between the two groups.

RESULTS

All patients were followed up at least 5 years. There was no difference in range of motion and Knee Society Score between the two groups before surgery and at last follow-up after surgery (p > 0.05). In the PVNS group, no patients with the recurrence of PVNS were found at the last follow-up, one patient underwent revision surgery due to periprosthetic fracture, and three patients had stiffness one year after surgery (17.6% vs 1.5%, p = 0.005; ROM 16-81°), but no revision was needed. At 7 years, the implant survivorship was 90.0% in the PVNS group and 96.6% in the control group (p = 0.54).

CONCLUSIONS

This study demonstrated that the function of patients with PVNS who underwent CR TKA had been significantly improved, and the survival rate of implants in these patients was similar to the patients with OA. Consequently, the patients with PVNS who underwent CR TKA might be an achievable option. However, these patients should pay more attention to the occurrence of postoperative stiffness complications.

Anti-fibrotic effects of the antihistamine ketotifen in a rabbit model of arthrofibrosis

Aims

Arthrofibrosis is a relatively common complication after joint injuries and surgery, particularly in the knee. The present study used a previously described and validated rabbit model to assess the biomechanical, histopathological, and molecular effects of the mast cell stabilizer ketotifen on surgically induced knee joint contractures in female rabbits.

Methods

A group of 12 skeletally mature rabbits were randomly divided into two groups. One group received subcutaneous (SQ) saline, and a second group received SQ ketotifen injections. Biomechanical data were collected at eight, ten, 16, and 24 weeks. At the time of necropsy, posterior capsule tissue was collected for histopathological and gene expression analyses (messenger RNA (mRNA) and protein).

Results

At the 24-week timepoint, there was a statistically significant increase in passive extension among rabbits treated with ketotifen compared to those treated with saline (p = 0.03). However, no difference in capsular stiffness was detected. Histopathological data failed to demonstrate a decrease in the density of fibrous tissue or a decrease in α-smooth muscle actin (α-SMA) staining with ketotifen treatment. In contrast, tryptase and α-SMA protein expression in the ketotifen group were decreased when compared to saline controls (p = 0.007 and p = 0.01, respectively). Furthermore, there was a significant decrease in α-SMA (ACTA2) gene expression in the ketotifen group compared to the control group (p < 0.001).

Conclusion

Collectively, these data suggest that ketotifen mitigates the severity of contracture formation in a rabbit model of arthrofibrosis.

Manipulation under anesthesia as a therapy option for postoperative knee stiffness: a retrospective matched-pair analysis

INTRODUCTION

Due to demographic changes, total knee arthroplasty (TKA) is one of the most frequently performed orthopedic surgeries. Therapies for associated postoperative complications, such as postoperative knee stiffness (PKS), are becoming increasingly important. The aim of this retrospective matched-pair analysis was to evaluate mid-term-results following manipulation under anesthesia (MUA).

MATERIALS AND METHODS

Fifty-one patients with PKS were evaluated and 51 matched-pair patients without PKS after primary TKA were chosen for the control group. In addition to the range of motion, the functionality was recorded by Knee Society Score (KSS), Western Ontario and Mc Masters Universities Osteoarthritis Index (WOMAC), and Short-Form-12 Questionnaire (SF-12). Experience of pain was mapped using a 10-point Numeric Rating Scale (NRS), and the analgesic requirement was mapped using the WHO step scheme. A final follow-up examination was conducted approximately three years after TKA. To evaluate potential risk factors for the development of PKS, TKA alignment was measured via postoperative X-ray images.

RESULTS

Improvement of the average knee flexion of 35.7° and total flexion of 107.4° was detected in PKS patients after MUA. The flexion of the control group was 112.4°; no significant between-group difference was present regarding prosthesis type, sex, age and BMI. Regarding KSS, WOMAC, and SF-12, the MUA cohort achieved statistically-relevant lower overall scores than the control group, p = 0.006, p = 0.005, p = 0.001, respectively. Significantly higher experiences of pain and a higher need for analgesics in MUA patients were reported (p = 0.001 and p < 0.001, respectively). Radiological evaluation of the prosthesis alignment did not show any differences between the two groups.

CONCLUSIONS

MUA can improve mobility after PKS, whereby MUA seemed to be a functional therapy option for PKS. Compared to the control group, the MUA group showed lower functional values and an increased experience of pain. A correlation between prosthesis malalignment and MUA could not be detected radiologically. Further studies are necessary to investigate the reasons for PKS.

Manipulation under Anaesthesia for Patient Reported Stiffness after Total Knee Arthroplasty in an Asian Population

Introduction:

Stiffness after Total Knee Arthroplasty (TKA) is a complication that decreases patient satisfaction. Patients in an Asian population have potentially different requirements of knee range of motion. The authors have encountered patients who complain of subjective stiffness post TKA who do not have a severely restricting range of motion (ROM). Some patients have persistent subjective stiffness and undergone Manipulation Under Anaesthesia (MUA). We look at their functional outcomes post MUA.

Materials and Methods:

This is a retrospective study, including 48 patients from a single institution who underwent MUA for stiffness, separated into objective and subjective knee stiffness. Patients with subjective knee stiffness who underwent MUA had failed conservative management. ROM, Oxford Knee Scores (OKS), Knee Society Scores (KSS) and Short Form 36 (SF36) scores were compared at two years post MUA.

Results:

The demographics of the two patient groups were similar. The time interval between index TKA and MUA was higher in the subjective knee stiffness group. Pre-MUA OKS, KS Function Score, KSS and SF36 scores were similar in both patient subgroups. There was no significant difference in the OKS, KSS or SF36 at two year follow-up. The proportion of patients in each group who achieved the Minimum Clinically Important Difference (MCID) improvement in the scores was also similar.

Conclusions:

Patients with subjective knee stiffness can achieve similar functional outcome improvements in Oxford and Knee Society Scores with MUA at two years follow-up.

Efficacy of manipulation under anesthesia beyond three months following total knee arthroplasty

Background

Stiffness after total knee arthroplasty (TKA) is often treated with manipulation under anesthesia (MUA) to improve range of motion (ROM). However, many authors recommend against MUA beyond 3 months after TKA. This study investigates the timing of MUA for stiffness after TKA, focusing on MUA performed at >12 weeks.

Methods

In total, 142 MUAs were retrospectively reviewed. “Early” MUAs were at <12 weeks after TKA; “Late” MUAs were >12 weeks. MUAs were further subdivided into 4 groups: 83 “Group I” cases at <12 weeks, 34 “Group II” between 12 and 26 weeks, 12 “Group III” between 26 and 52 weeks, and 13 “Group IV” at >52 weeks. Gains in ROM were compared between groups.

Results

Gains in flexion and overall ROM were statistically equivalent in Early vs Late MUA when controlling for pre-MUA ROM. ROM gains between the early Group I and the later Groups II-IV were also statistically comparable. Overall ROM gain in Group I was 24.1°, 17.9° in Group II, 20.8° in Group III, and 11.1° in Group IV. There were no significant complications.

Conclusions

Early and late MUA resulted in statistically equivalent gains in ROM, regardless of timing after TKA. All groups showed an average improvement in ROM of ≥11°. MUA performed beyond 3 months, and even beyond 1 year, appears to be safe and may improve ROM and allow select patients to avoid revision surgery.

The stiff total knee arthroplasty: causes, treatment modalities and results

It is clear that the stiff total knee arthroplasty (TKA) is a multifactorial entity associated with preoperative, intraoperative and postoperative factors.

Management of the stiff TKA is best achieved by preventing its occurrence using strategies to control preoperative factors, avoid intraoperative technical errors and perform aggressive, painless postoperative physical medicine and rehabilitation; adequate pain control is paramount in non-invasive management.

Careful attention to surgical exposure, restoring gap balance, minimizing surgical trauma to the patellar ligament/extensor mechanism, appropriate implant selection, pain control and adequate physical medicine and rehabilitation (physiotherapy, Astym therapy) all serve to reduce its incidence.

For established stiff TKA, there are multiple treatment options available including mobilization under anaesthesia (MUA), arthroscopic arthrolysis, revision TKA, and combined procedures.

Cite this article: EFORT Open Rev 2019;4:602-610. DOI: 10.1302/2058-5241.4.180105

Manipulation under anesthesia after primary knee arthroplasty in Sweden: incidence, patient characteristics and risk of revision

Background and purpose - The incidence of manipulation under anesthesia (MUA) after knee arthroplasty surgery has been reported to vary between 0.5% and 10%. We evaluated the incidence of MUA after primary knee arthroplasty in Sweden, the demographics of the patients and the risk of revision. Patients and methods - Between 2009 and 2013, 64,840 primary total and unicompartmental knee arthroplasties (TKA and UKA) were registered in the Swedish Knee Arthroplasty Register (SKAR). MUAs performed between 2009 and 2014 were identified through the in- and outpatient registers of the Swedish National Board of Health and Welfare. Pertinent data were verified through medical records and patient demographics and revisions were obtained from the SKAR. Results - 1,258 MUAs were identified. Of these, 1,078 were 1st-time MUAs, performed within 1 year after the primary knee arthroplasty. The incidence of MUA was 1.7% and the incidence varied between hospitals from 0% to 5%. The majority were performed after TKA (98%), in younger patients (65% < 65 years), women (64%), and relatively healthy persons (88% had ASA ≤ 2). The cumulative risk of revision at 10 years was 10% (95% CI 8.6-12), similar for men and women. Interpretation - In Sweden, MUA is a rather uncommon measure after knee arthroplasty, especially after UKA. The CRR at 10 years was doubled compared to the general knee arthroplasty population. The frequency of the procedure varies between hospitals but in general it is performed more frequently in healthier and younger patients.

Prediction of the need for manipulation under anesthesia for flexion contracture after total knee arthroplasty in patients of advanced age

Objective

This study was performed to develop a prediction model for requiring manipulation under anesthesia (MUA) for flexion contracture after total knee arthroplasty (TKA) in patients of advanced age.

Methods

We retrospectively reviewed 269 patients of advanced age undergoing primary TKA in one center with a minimum 1-year follow-up. Patients who underwent postoperative MUA had flexion contracture of >10° after 4 weeks of postoperative rehabilitation, and their demographic data and preoperative clinical conditions [knee diagnosis, diabetes mellitus, hypertension, lumbar spinal disorders, hip disorders, ankle disorders, knee deformity (varus/valgus), preoperative flexion contracture (PFC), range of motion (ROM), and Hospital for Special Surgery (HSS) knee score] were compared with those of patients without MUA. All preoperative factors were collected to develop the predictive model.

Results

Thirty patients underwent MUA. Patients who underwent MUA after surgery had significant differences in PFC, higher HSS knee scores before surgery (59.10 ± 7.22 vs. 55.70 ± 13.09), and lower preoperative ROM (81.57 ± 30.86 vs. 95.47 ± 24.36) than those who did not undergo MUA.

Conclusion

A prediction model for MUA in advanced-age patients with flexion contracture was developed and mainly consisted of preoperative risk factors including PFC, HSS scores, and ROM.

Astym® therapy: a systematic review

Soft tissue dysfunction can result from the degeneration of tissues as in the case of degenerative tendinopathy or from the build-up of problematic scar tissue, which can be the result of several aggravating factors, including overuse injuries, acute or chronic trauma, or as a result of surgery. This dysfunction often results in impaired movement, pain, and swelling of the affected area, which can lead to patient dissatisfaction and a lower quality of life. These soft tissue dysfunctions also have a marked economic impact. Although a number of traditional treatments attempt to address these issues, no optimal treatment choice has emerged. Traditional treatments are not always successful, can be invasive, and can consume many medical resources. A relatively new treatment approach, Astym therapy, is a potentially useful, non-invasive, more cost-effective option. This therapy was developed to address soft-tissue dysfunctions by stimulating the regeneration of soft tissues and the resorption of inappropriate scar tissue/fibrosis. It has been reported to help with the resorption and remodeling of abnormal tissue, thereby leading to improved motion, function and pain relief. The purpose of this analysis was to review the published literature related to Astym therapy on various musculoskeletal disorders. Specifically, we evaluated the effectiveness of this therapeutic method on disorders related to the: (I) knee; (II) upper extremity; (III) hamstring muscles; and (IV) ankle and Achilles tendon injuries.

Alternative technique for knee manipulation under anesthesia

Total knee arthroplasty is a successful surgery for the majority of patients with osteoarthrosis of the knee. Approximately 5% of patients undergoing total knee arthroplasty experience loss of motion or arthrofibrosis. Manipulation under anesthesia (MUA) is generally indicated for patients who do not achieve >90° of flexion by 6-12 weeks postoperatively. Complications from MUA are rare but can be devastating. We describe a novel technique for MUA with no reported major complications in our review of 78 patients. The average flexion improved from 80.0 (±3.8) before manipulation to 115.4 (±2.1) after manipulation. There were no major complications including fracture or extensor mechanism injury.

Smartphone technology: a reliable and valid measure of knee movement in knee replacement

Knee range of motion (ROM) following a knee arthroplasty is an important clinical outcome that directly relates to the patient's physical function. Smartphone technology has led to the creation of applications that can measure ROM. The aim was to determine the concurrent reliability and validity of the photo-based application 'Dr Goniometer' (DrG) compared with a universal goniometer performed by a clinician. A smartphone camera was used to take photographs of the knee in full flexion and full extension, and the images were sent by participants to a study phone. Participants then rated the ease of participation. To assess validity, the patient's knee was measured by a clinician using a goniometer. To examine reliability, four clinicians assessed each image using DrG on four separate occasions spaced 1 week apart. A total of 60 images of knee ROM for 30 unicondylar or total knee arthroplasty were assessed. The goniometer and DrG showed strong correlations for flexion (r=0.94) and extension (r=0.90). DrG showed good intrarater reliability and excellent inter-rater reliability for flexion (intraclass correlation coefficient=0.990 and 0.990) and good reliability for extension (intraclass correlation coefficient=0.897 and 0.899). All participants found the process easy. DrG was proven to be a valid and reliable tool in measuring knee ROM following arthroplasty. Smartphone technology, in conjunction with patient-reported outcomes, offers an accurate and practical way to remotely monitor patients. Benefit may be found in differentiating those who need face-to-face clinical consult to those who do not.

Protocol-Driven Revision for Stiffness After Total Knee Arthroplasty Improves Motion and Clinical Outcomes

BACKGROUND

Stiffness after revision total knee arthroplasty (TKA) is a difficult problem without a well-defined treatment algorithm. The purpose of this study was to evaluate the results of revision TKA for stiffness within the context of differential component replacement.

METHODS

Consecutive patients who underwent revision TKA were retrospectively identified and included those who received debridement and polyethylene liner exchange alone, revision of only one of the femoral or tibial fixed components, or revision of all components. Preoperative and postoperative range of motion and Knee Society score (KSS) were collected.

RESULTS

Sixty-nine knees were included in the study group with a mean follow-up of 43 months (range, 12-205 months). The mean prerevision flexion contracture of 17° improved to 5° after surgical intervention (P < .001). Similarly, mean flexion and motion arc improved from 70° to 92° and from 53° to 87°, respectively (P < .001). Mean KSS knee scores improved from 42 to 70 and KSS function scores improved from 41 to 68 (P < .001). Mean arc of motion improved by 45° in patients who underwent complete component revision, 32° with component retention, and 29° with single component revision (P = .046). KSS knee scores improved by 34, 25, and 28 points in these respective groups (P = .049). KSS function scores improved by 33, 27, and 25 points (P = .077).

CONCLUSION

Revision surgery with or without component revision can improve motion and function in patients with stiffness after TKA. Complete component revision may offer the largest improvements in these outcome measures in properly selected patients.

The effect of a preoperative education class on the rate of manipulation under anesthesia after total knee arthroplasty in a veterans population

Background

Arthrofibrosis after total knee arthroplasty (TKA) is a common complication, potentially occurring in up to 25% of patients, and may be treated during the early recovery period by manipulation under anesthesia (MUA). The majority of preoperative factors that predispose patients to postoperative stiffness are patient specific and not modifiable. The United States Veteran Affairs is a particularly challenging group given a higher baseline rate of medical comorbidities and opioid dependence than the general population. Patient education about postoperative expectations and complications has been shown to improve outcomes in certain orthopedic procedures. This retrospective study aims to determine if preoperative counseling for veterans undergoing primary TKA reduces the rate of postoperative stiffness, and consequently MUA, in this subset of patients.

Methods

We evaluated the medical records of 244 veterans at a single veteran affairs hospital who underwent 278 TKAs during a 6-year period under one surgeon. Patients were separated into groups based on attendance in the preoperative counseling session. Effects of various factors, including age, sex, body mass index, preoperative knee range of motion, and history of previous knee surgery, were compared between these 2 cohorts.

Results

Attendance in the preoperative course did not have a statistically significant impact on the rate of manipulation (odds ratio [OR], 1.07). Female gender and prior manipulation had an increased OR of knee manipulation, whereas age > 65 years had a decreased OR that did not reach significance.

Conclusions

Our results show that preoperative counseling did not have a benefit in terms of postoperative MUA rates in veterans. Preoperative education may be helpful for setting appropriate expectations of pain, recovery, and function after total joint arthroplasty and may be useful in an online or video format in small practices in which cost may be prohibitive. Further studies are needed to determine whether they provide any benefit in postoperative arthrofibrosis rates.

Efficacy of Manipulation Under Anesthesia for Stiffness Following Total Knee Arthroplasty: A Systematic Review

BACKGROUND

Knee stiffness following primary total knee arthroplasty can lead to unsatisfactory patient outcomes secondary to persistent pain and loss of function. Manipulation under anesthesia (MUA) remains a viable option for treatment of post-operative stiffness. However, the optimal timing and clinical efficacy of manipulation of anesthesia remains unknown.

METHODS

A systematic review of the literature was performed to identify studies that reported clinical outcomes for patients who underwent MUA for post-operative stiffness treatment. Repeat MUA procedures were included in the study but were analyzed separately.

RESULTS

Twenty-two studies (1488 patients) reported on range of motion (ROM) after MUA, and 4 studies (81 patients) reported ROM after repeat MUA. All studies reported pre-MUA motion of less than 90°, while mean ROM at last follow-up exceeded 90° in all studies except 2. For studies reporting ROM improvement following repeat MUA, the mean pre-manipulation ROM was 80° and the mean post-manipulation ROM was 100.6°.

CONCLUSION

MUA remains an efficacious, minimally invasive treatment option for post-operative stiffness following TKA. MUA provides clinically significant improvement in ROM for most patients, with the best outcomes occurring in patients treated within 12 weeks post-operatively.

PROSPERO REGISTRATION NUMBER

CRD42016052215.

Risk Factors, Outcomes, and Timing of Manipulation Under Anesthesia After Total Knee Arthroplasty

BACKGROUND

Knee stiffness requiring manipulation under anesthesia (MUA) is an undesirable outcome following total knee arthroplasty (TKA), but risk factors for, and optimal timing of, MUA remain unclear.

METHODS

Primary TKAs performed at a single center were retrospectively reviewed. Clinical variables were compared between patients who underwent MUA and those who did not; variables that differed were utilized to identify an appropriately matched control group of non-MUA patients. The MUA group was divided into early (MUA ≤6 weeks from index) and late (>6 weeks) subgroups. Flexion values at multiple time points were compared.

RESULTS

In total, 1729 TKA patients were reviewed; MUA was performed in 62 patients. Patients undergoing MUA were younger (55.2 vs 65.3 years, P < .001) and had higher rates of current smoking (21.0% vs 7.3%, P < .001) and prior procedure (59.7% vs 40.4%, P = .002), most commonly arthroscopy; a control group of patients not requiring MUA, matched on the basis of these variables, was identified. While no difference in pre-TKA flexion existed across groups, final flexion in the early MUA group (106.7°) was equivalent to that of controls (115.6°), while final flexion in the late MUA group was not (101.3°, P = .001).

CONCLUSION

TKA patients undergoing MUAs were younger, more likely to be current smokers, and more likely to have undergone prior knee surgery. Even in patients with severe initial postoperative limitations in range of motion, MUA within 6 weeks may allow for final outcomes that are equivalent to those experienced by similar patients not requiring manipulation.

Outpatient Total Knee Arthroplasty Is Associated with Higher Risk of Perioperative Complications

BACKGROUND

As concerns regarding health-care expenditure in the U.S. remain at the national forefront, outpatient arthroplasty is an appealing option for carefully selected patient populations. The purpose of this study was to determine the nationwide trends and complication rates associated with outpatient total knee arthroplasty (TKA) in comparison with standard inpatient TKA.

METHODS

We performed a retrospective review of the Humana subset of the PearlDiver Patient Record Database to identify patients who had undergone TKA (Current Procedural Terminology [CPT] code 27447) as either outpatients or inpatients from 2007 to 2015. The incidence of perioperative medical and surgical complications was determined by querying for relevant International Classification of Diseases, Ninth Revision (ICD-9) and CPT codes. Multivariate logistic regression analysis adjusted for age, sex, and Charlson Comorbidity Index (CCI) was used to calculate odds ratios (ORs) of complications among outpatients relative to inpatients treated with TKA.

RESULTS

Cohorts of 4,391 patients who underwent outpatient TKA and 128,951 patients who underwent inpatient TKA were identified. The median age was in the 70 to 74-year age group in both cohorts. The incidence of outpatient TKA increased across the study period (R = 0.60, p = 0.015). After adjustment for age, sex, and CCI, outpatient TKAs were found to more likely be followed by tibial and/or femoral component revision due to a noninfectious cause (OR = 1.22, 95% confidence interval [CI] = 1.01 to 1.47; p = 0.039), explantation of the prosthesis (OR = 1.35, CI = 1.07 to 1.72; p = 0.013), irrigation and debridement (OR = 1.50, CI = 1.28 to 1.77; p < 0.001), and stiffness requiring manipulation under anesthesia (OR = 1.28, CI = 1.17 to 1.40; p < 0.001) within 1 year. Outpatient TKA was also more frequently associated with postoperative deep vein thrombosis (OR = 1.42, CI = 1.25 to 1.63; p < 0.001) and acute renal failure (OR = 1.13, CI = 1.01 to 1.25; p = 0.026).

CONCLUSIONS

With the potential to minimize arthroplasty costs among healthy patients, outpatient TKA is an increasingly popular option. Nationwide data from a private insurance database demonstrated a higher risk of perioperative surgical and medical complications including component failure, surgical site infection, knee stiffness, and deep vein thrombosis.

LEVEL OF EVIDENCE

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

Long-term outcome of knee arthroplasty in the setting of pigmented villonodular synovitis

BACKGROUND

Pigmented villonodular synovitis (PVNS) is a rare, benign proliferation of the synovium, commonly affecting the knee. Arthroplasty can successfully manage arthrosis in this population; however, outcome data is limited. The purpose of this study was to investigate the oncologic and functional outcome of patients undergoing total knee arthroplasty (TKA) in the setting of PVNS.

METHODS

48 patients were identified at our institution with histologically confirmed PVNS that subsequently received TKA. The cohort consisted of 28 females and 20 males with a mean age and body mass index of 61years and 29.2kg/m². 37patients had "active" disease, defined as diffuse in 40 patients and focal in eight. Mean follow-up was 14years.

RESULTS

The 10-year disease free-survival was 88%. Recurrence occurred in 6 patients and was treated with synovectomy and revision arthroplasty (n=4), local excision (n=1) and transfemoral amputation (n=1). 25 patients sustained at least 1 complication, most commonly decreased knee range of motion. Complications resulted in revision TKA in 10 patients (21%). There was no difference (P=0.74) between mean pre- and postoperative ROM; however, there was a significant reduction in the number of patients with a flexion contracture >15° (P=0.03). The mean Knee Society score and functional score significantly improved following surgery (P<0.001).

CONCLUSIONS

This study indicates arthroplasty in the setting of PVNS improves patient function and reduces the presence of flexion contractures. Patients with a history of PVNS should be cautioned when undergoing arthroplasty on the elevated risk of subsequent procedures.

LEVEL OF EVIDENCE

Level III.

Arthrofibrosis Associated With Total Knee Arthroplasty

BACKGROUND

Arthrofibrosis is a debilitating postoperative complication of total knee arthroplasty (TKA). It is one of the leading causes of hospital readmission and a predominant reason for TKA failure. The prevalence of arthrofibrosis will increase as the annual incidence of TKA in the United States rises into the millions.

METHODS

In a narrative review of the literature, the etiology, economic burden, treatment strategies, and future research directions of arthrofibrosis after TKA are examined.

RESULTS

Characterized by excessive proliferation of scar tissue during an impaired wound healing response, arthrofibrotic stiffness causes functional deficits in activities of daily living. Postoperative, supervised physiotherapy remains the first line of defense against the development of arthrofibrosis. Also, adjuncts to traditional physiotherapy such as splinting and augmented soft tissue mobilization can be beneficial. The effectiveness of rehabilitation on functional outcomes depends on the appropriate timing, intensity, and progression of the program, accounting for the patient's ability and level of pain. Invasive treatments such as manipulation under anesthesia, debridement, and revision arthroplasty improve range of motion, but can be traumatic and costly. Future studies investigating novel treatments, early diagnosis, and potential preoperative screening for risk of arthrofibrosis will help target those patients who will need additional attention and tailored rehabilitation to improve TKA outcomes.

CONCLUSION

Arthrofibrosis is a multi-faceted complication of TKA, and is difficult to treat without an early, tailored, comprehensive rehabilitation program. Understanding the risk factors for its development and the benefits and shortcomings of various interventions are essential to best restore mobility and function.

High Rate of Local Recurrence and Complications Following Total Knee Arthroplasty in the Setting of Synovial Chondromatosis

BACKGROUND

Synovial chondromatosis is a rare, monoarticular arthropathy due to synovial metaplasia. There is a paucity of data examining the outcome of total knee arthroplasty (TKA) in the setting of synovial chondromatosis. The purpose of this study is to investigate the outcome and function in patients undergoing TKA for management of synovial chondromatosis.

METHODS

Twenty patients who received TKA for synovial chondromatosis over a 25-year period were identified for analysis and followed for a mean of 7 years. There were 12 males and 8 females, with a mean age and body mass index of 63 years and 30.7 kg/m². Seventeen patients had "active" disease at the time of surgery.

RESULTS

The 5-year disease-free survival was 73%. Five patients sustained a recurrence that was treated with synovectomy and revision TKA (n = 2), observation (n = 2), and transfemoral amputation (n = 1) due to malignant degeneration to chondrosarcoma. One of the revision TKA patients underwent a transfemoral amputation 4 months later for recurrence. The overall rate of amputation was 10%. Nine patients (45%) sustained a complication, most commonly decreased knee motion (n = 7), leading to a revision TKA in 3 patients (15%). Mean preoperative knee range of motion was 73°, which improved to 97° postoperatively. The Knee Society Score and functional assessment improved from 35 and 42 preoperatively to 74 and 67 following TKA.

CONCLUSION

TKA in the setting of synovial chondromatosis improves patient function and knee range of motion; however, there is a high rate of local recurrence and complications.

International consensus on the definition and classification of fibrosis of the knee joint

AIMS

The aim of this consensus was to develop a definition of post-operative fibrosis of the knee.

PATIENTS AND METHODS

An international panel of experts took part in a formal consensus process composed of a discussion phase and three Delphi rounds.

RESULTS

Post-operative fibrosis of the knee was defined as a limited range of movement (ROM) in flexion and/or extension, that is not attributable to an osseous or prosthetic block to movement from malaligned, malpositioned or incorrectly sized components, metal hardware, ligament reconstruction, infection (septic arthritis), pain, chronic regional pain syndrome (CRPS) or other specific causes, but due to soft-tissue fibrosis that was not present pre-operatively. Limitation of movement was graded as mild, moderate or severe according to the range of flexion (90° to 100°, 70° to 89°, < 70°) or extension deficit (5° to 10°, 11° to 20°, > 20°). Recommended investigations to support the diagnosis and a strategy for its management were also agreed.

CONCLUSION

The development of standardised, accepted criteria for the diagnosis, classification and grading of the severity of post-operative fibrosis of the knee will facilitate the identification of patients for inclusion in clinical trials, the development of clinical guidelines, and eventually help to inform the management of this difficult condition. Cite this article: Bone Joint J 2016;98-B:1479-88.

The risk of manipulation under anesthesia due to unsatisfactory knee flexion after fast-track total knee arthroplasty

BACKGROUND

Fast-track TKA has significantly shortened the time available for physiotherapists to optimize knee ROM before discharge. Safety aspects concerning knee stiffness and the need for manipulation in a fast-track setting need to be illuminated. The study aims were to analyze if fast-track TKA can be considered safe considering rates of knee manipulation and if there is an association between knee ROM at time of discharge and the need for later manipulation.

METHODS

Primary TKAs operated in 2011 at our institution were eligible for inclusion. The study group consisted of 359 TKAs.

RESULTS

Manipulation of the knee was performed in 21 of 359 TKAs (5.8%). Seventy-one percent were discharged with a flexion ≥70° combined with an extension deficit of ≤10°. The occurrence of MUA for these patients was 4.3%. The prevalence of knee manipulation showed a statistically significant association with the achieved knee flexion at discharge (p=0.02). Median length of stay was two days.

CONCLUSION

Compared with literature findings fast-track TKA surgery may be considered safe based on the acceptable rate of knee manipulations after TKA (5.8%). We suggest ROM of ≥70° flexion combined with an extension deficit of ≤10° as an "optimal-zone" for ROM at discharge. The reason for this is the low occurrence of MUA (4.3%) in relation to the large amount of TKAs it represents (71%). The indication for MUA is multifactorial and ROM at discharge serves only as an indicator of later MUA risk.

Arthroscopic Posterior Knee Capsulotomy for a Fixed Flexion Contracture in a Ten-Year-Old Boy Due to a Hypertrophied Ligamentum Mucosum: A Case Report

CASE

Knee flexion contractures are difficult to treat effectively. We present the case of a ten-year-old boy with a flexion contracture due to a hypertrophied ligamentum mucosum treated with an arthroscopic posterior capsular release. The patient obtained full extension and maintained it at the time of final follow-up.

CONCLUSION

This case represents a unique cause of an impinging ligamentum mucosum and provides anecdotal support to the concept of an arthroscopic posterior capsular release as a safe and effective option for flexion contractures.

No clinical benefit of titanium nitride coating in cementless mobile-bearing total knee arthroplasty

PURPOSE

Titanium nitride (TiN) coating of cobalt-chromium-molybdenum (CoCrMo) implants has shown to improve the biomechanical properties of the implant surface and to reduce adhesive wear in vitro. It is yet unknown whether TiN coating of total knee prosthesis (TKP) affects the postoperative clinical outcome of total knee arthroplasty (TKA).

METHODS

In a double-blind randomized controlled clinical trial, 101 patients received an uncemented mobile-bearing CoCrMo TKP, either TiN coated or uncoated. Primary outcome measure visual analogue scale (VAS) score for pain, and secondary outcome measures Knee Society Score (KSS), revision rate and adverse events, range of motion of the knee as well as knee circumference and knee skin temperature were assessed 6 weeks, 6 months, 1 year and 5 years postoperative. Repeated measures analysis was used to evaluate the postoperative outcome measures over time.

RESULTS

There was no difference between the two groups in VAS score, KSS, revision rate, range of motion of the knee, knee circumference and knee skin temperature. There were no adverse events that could be related to the TiN coating.

CONCLUSIONS

TiN-coated TKP does not influence the postoperative outcome of uncemented mobile-bearing TKA regarding postoperative pain, revision rate, range of motion, swelling and temperature of the knee. Therefore, TiN coating of CoCrMo TKP has no clinical benefit on the outcome of cementless mobile-bearing TKA.

LEVEL OF EVIDENCE

Therapeutic study, Level I.

Do various factors affect the frequency of manipulation under anesthesia after primary total knee arthroplasty?

BACKGROUND

One of the most important goals of primary total knee arthroplasty (TKA) is to achieve a functional range of motion (ROM). However, up to 20% of patients fail to do so, which can impair activities of daily living.

QUESTIONS/PURPOSES

The purpose of this study was to evaluate the effect of various (1) demographic factors; (2) comorbidities; and (3) knee-specific factors on the frequency of manipulation under anesthesia, which was used as an indicator of knee stiffness after a primary TKA.

METHODS

We evaluated the registries of two high-volume centers and reviewed all 3182 TKAs that were performed between 2005 and 2011 to identify all patients who had undergone manipulation under anesthesia (MUA). A total of 156 knees in 133 patients underwent MUA after an index arthroplasty. These patients were compared in a one-to-four ratio with a group of patients with satisfactory ROM drawn from the same database who met prespecified criteria and who had not undergone MUA. Effects of various factors, including age, sex, body mass index, race, comorbidities, and the underlying cause of knee arthritis, were compared between these two cohorts using multivariable logistic regressions.

RESULTS

After controlling for various confounding, nonwhite race was associated with an increase (odds ratio [OR], 2.01; p=0.03), and age≥65 years (OR, 0.17; 95% confidence interval [CI], 0.04-0.74; p=0.0179) was associated with a reduction in the incidence of MUA. In comorbidities, diabetes (OR, 1.72; 95% CI, 1.02-2.32; p=0.03), high cholesterol levels (OR, 2.70; p=0.03), and tobacco smoking (OR, 1.59; 95% CI, 1.03-2.47; p=0.03) were associated with an increase in frequency of MUA. In knee-specific factors, preoperative knee ROM of less than 100° (OR, 0.80; p<0.0001) and knee osteonecrosis (p=3.61; 95% CI, 1.29-10.1; p=0.014) were associated with increased frequency of MUA.

CONCLUSIONS

We identified several demographic, medical, and knee-specific factors that were associated with poor postoperative ROM in our patients undergoing TKA. Patients who have multiple risk factors may benefit from preoperative counseling to set realistic ROM expectations.

LEVEL OF EVIDENCE

Level III, prognostic study. See Guidelines for Authors for a complete description of levels of evidence.

The effect of timing of manipulation under anesthesia to improve range of motion and functional outcomes following total knee arthroplasty

BACKGROUND

Manipulation under anesthesia has been reported to improve range of motion when other rehabilitative efforts fail to obtain adequate motion after total knee arthroplasty. The purpose of this study was to evaluate the effects of the timing of the manipulation on knee range of motion and clinical outcomes.

METHODS

All 2128 total knee arthroplasties performed at our institution from 2005 to 2011 were reviewed to determine the number of patients who had undergone manipulation under anesthesia. A total of 144 manipulations in eighty-eight women and forty-five men were reviewed. Manipulations under anesthesia that were performed within the first twelve weeks after total knee arthroplasty were considered early and those after that period were considered late. Patients were further substratified according to the timing of the manipulation: Group I included those who had the manipulation within six weeks; Group II, at seven to twelve weeks; Group III, at thirteen to twenty-six weeks; and Group IV, after twenty-six weeks. Outcomes evaluated included gains in flexion and final range of motion, and Knee Society objective and function scores between early and late manipulation, using various adjusted multivariable regression models and at a mean follow-up of fifty-one months (range, twelve to eighty-one months). Mediation analysis was used to investigate whether gains in range of motion from the manipulations under anesthesia alone had mediated the effect between the timing of the manipulation and the clinical outcomes.

RESULTS

Patients who underwent early manipulation had a significantly higher mean gain in flexion (36.5° versus 17°), higher final range of motion (119° versus 95°), and higher Knee Society objective (89 versus 84 points) and function scores (88 versus 83 points) than those who had late manipulation under anesthesia. There were no significant differences in the outcomes of Groups I and II. Manipulations after twenty-six weeks resulted in unsatisfactory clinical outcomes. Multivariable regression analyses confirmed significantly better clinical outcomes with early manipulation. Mediation analysis showed that the timing of manipulation independently had significantly contributed to the outcomes.

CONCLUSIONS

Orthopaedic surgeons should have a low threshold for performing early manipulations with the patient under anesthesia within twelve weeks after an arthroplasty, to achieve higher knee range of motion and improved clinical outcomes.

LEVEL OF EVIDENCE

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