The efficacy of arthroscopy following total knee replacement

Knee Arthroscopy Following Total Knee Arthroplasty is Not Associated With an Elevated Risk of Infection

BACKGROUND

Recent literature has suggested that knee arthroscopy (KA) following ipsilateral primary total knee arthroplasty (TKA) may be associated with an increased risk of periprosthetic joint infection (PJI). However, prior studies on this subject have relied on insurance databases or have lacked control groups for comparison. This study aimed to evaluate the risk of PJI in patients undergoing ipsilateral KA after primary TKA at a single institution.

METHODS

Our total joint registry was queried to identify 167 patients (178 knees) who underwent ipsilateral KA for any indication other than infection following primary TKA (KA + TKA group). The average time from TKA to KA was 2.1 ± 2.3 years. The average follow-up from primary TKA and from KA was 8.4 ± 5.4 years and 6.3 ± 5.4 years, respectively. The mean patient age was 63 ± 11 years, the mean body mass index was 31 ± 5, and 64% were women. The most common indications for KA were patellar clunk or patellofemoral synovial hyperplasia (66%) and arthrofibrosis (16%). Patients in the KA + TKA group were matched to 523 patients who underwent TKA without subsequent KA (TKA group) based on age, sex, date of surgery, and body mass index. The primary outcome measure was survivorship free from PJI.

RESULTS

There was no statistical difference in the overall rate of PJI between the KA + TKA group (n = 2, 1.1%) compared to the TKA group (n = 3, 0.6%) (hazard ratio 2.0, 95% confidence interval 0.3 to 12.0, P = .4). At 5 and 10 years after TKA, there was no difference in survivorship free of PJI between the 2 groups (P = .8 and P = .3, respectively).

CONCLUSIONS

A PJI is a rare complication of KA after TKA. The rate of PJI in patients undergoing KA following TKA is not significantly increased.

LEVEL OF EVIDENCE

III.

Association Between Power Doppler Ultrasound Signals and Chronic Pain After Total Knee Arthroplasty: A Cross-Sectional Explorative Study

Purpose

Some patients experience chronic postsurgical pain (CPSP) after total knee arthroplasty (TKA) despite the absence of clinical or radiographic abnormalities. Postoperative synovitis as a cause of CPSP after TKA has received limited research attention. This study aimed to investigate the relationship between synovitis after TKA and CPSP.

Patients and Methods

A total of 111 knees of 85 patients, with at least 1-year post-TKA follow-up, were assessed retrospectively and cross-sectionally. Power Doppler (PD) ultrasonography was used to detect the synovial hypervascularity associated with synovitis. The knee joint was divided into 15 areas, and PD signals were graded semi-quantitatively (0-3) in each area, the sum of which was defined as the total PD score. Clinical information regarding CPSP, including the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain subscales, was recorded. The relationship between pain and PD ultrasonography findings was accessed. Patients were divided into two groups (CPSP+ and CPSP- groups) based on pain severity. Clinical information, including PD ultrasonography findings and other possible causes, was compared between the groups.

Results

The WOMAC pain subscale was significantly correlated with the total PD score and maximum PD grade (r=0.3977, p<0.0001; r=0.2797, p=0.0029; respectively). The CPSP+ group had a significantly higher maximum PD grade and total PD score than the CPSP- group (median [interquartile range]: 2 [1, 2] vs 1 [1, 2], p=0.0001; 6 [2, 11] vs 2 [1, 4], p=0.0002; respectively). Multiple and logistic regression analyses showed that the total PD score was an independent factor for the WOMAC pain subscale (β=0.3822, 95% confidence interval [CI]=0.1460, 0.6184, p=0.00176) and CPSP (odds ratio=1.19, 95% CI=1.01, 1.41, p=0.0424).

Conclusion

This study indicated a possible association between the total PD score and chronic pain after TKA; however, further studies are needed to corroborate these findings.

Knee Arthroscopy After Prior Total Knee ArthroplastyType of Study: Narrative Review

Total knee arthroplasty (TKA) results in substantial improvement for most patients with end-stage arthritis of the knee; however, approximately 20% of patients have an unsatisfactory result. Although many problems contributing to an unsatisfactory result after TKA are best addressed by revision TKA, some problems may be effectively addressed with arthroscopic treatment. The categories of pathology that can be addressed arthroscopically include peripatellar soft-tissue impingement (patellar clunk syndrome and patellar synovial hyperplasia), arthrofibrosis, and popliteus tendon dysfunction. Recognizing these disease entities and the role of arthroscopic surgery in the treatment of these lesions may be helpful in achieving a good outcome in certain patients who are unsatisfied with their knee arthroplasty.

Early outcomes of a novel bicruciate-retaining knee system: a 2-year minimum retrospective cohort study

INTRODUCTION

Bicruciate retaining (BCR) total knee arthroplasty (TKA) was designed to simulate natural knee kinematics and improve proprioception by retaining both the ACL and PCL. While the prospect of the design appears favorable to patients, previous designs have demonstrated modest survivorship rates compared to traditional designs. This study aims to report the early functional outcomes and implant survivorship of a novel BCR design.

MATERIALS AND METHODS

A multi-center, retrospective study was conducted identifying BCR TKA patients from 2016 to 2017. Patient demographics, quality outcomes, and post-operative complications were collected. A Kaplan-Meier analysis was used to evaluate revision-free survival.

RESULTS

One-hundred thirty-three patients with a mean follow-up time of 2.35 ± 0.25 years (range: 2.00-2.87 years) were identified. Patients receiving BCR TKA were, on average, 61.46 ± 9.27 years-old, obese (BMI = 31.80 ± 6.01 kg/m²), predominantly white (71.4%), and female (69.9%). The device was most often implanted using standard instruments (85.7%) compared to computer-assisted navigation (13.5%). Average length-of-stay was 1.77 ± 0.97 days. Six patients had a reoperation; three (2.5%) full revisions occurred for: infection (n = 1), arthrofibrosis (n = 1), and ACL rupture (n = 1); one (0.8%) tibial revision occurred for: arthrofibrosis; two (1.5%) liner exchanges occurred for: infection (n = 1) and arthrofibrosis (n = 1). Kaplan-Meier survivorship analysis of cumulative failure at 2-year showed a survival rate of 96.2% (95% confidence interval, 91.2-98.4%) for all-cause reoperation, 97.3% (91.6-99.1%) for aseptic revision, and 100% for mechanical failure.

CONCLUSION

Survivorship was 96.2% for all-cause reoperation, 97.3% for aseptic revision, and 100% for mechanical implant failure at 2-years. This novel BCR TKA demonstrated no implant-related complications and excellent survivorship outcomes over 2 years with comparable revision rates to those previously reported in the literature.

Anthropometric Measures of the Posterior Condyles: Gender Differences and Correlation to Implant Sizing

There is abundant data concerning morphological dimensions of the distal femur, particularly in women, which has led to redesign of the femoral component in total knee arthroplasty (TKA). Clinical experience reveals existing asymmetry of the femoral posterior condyles, yet current implant designs have a symmetrical femoral component. The objectives of this study were to analyze the dimensions of posterior condylar bone resection from a group of patients undergoing TKA and correlate the measurements to one prosthetic system. We retrospectively reviewed single surgeon morphological data from the posterior condyles of 105 knees during TKA. The study included 54 males and 51 females. Measurement of the posterior condylar bones was performed with a standard metric metal ruler by one investigator. Known dimensions of a single type of implant design were compared with the resection data. The average difference of posterior medial and lateral condylar width was 5.7 and 5.3 mm in males and females, respectively. The average host posterolateral condylar bone was 5.4 mm less than the trial implant across five sizes in both males and females. Results suggest that the dimension of the posterior lateral condyle is much smaller than the dimension of the implant in both groups of patients. Dimension of the posterior medial is close to dimension of the implant. Overhang of the component posterolaterally can create soft tissue irritation and result in postoperative pain and decreased range of motion. Our results increase awareness of the dimensions of the native posterolateral condyle and may influence future design of femoral implants used in total knee arthroplasty.

Arthrofibrosis after total knee arthroplasty: patients with keloids at risk

BACKGROUND

Arthrofibrosis remains one of the leading causes for revision in primary total knee arthroplasty (TKA). Similar in nature to arthrofibrosis, hypertrophic scars and keloid formation are a result of excessive collagen formation. There is paucity in the literature on whether there is an association between keloid formation and the development of arthrofibrosis following TKA. Therefore, the purpose of this study was to utilize a large nationwide database to identify and compare the rates of postoperative complications related to arthrofibrosis after primary TKA in patients with history of hypertrophic scar and keloid disorders versus those without.

METHODS

Patient records from 2010 to the second quarter of 2016 were queried from an administrative claims database, comparing rates of arthrofibrosis, manipulation under anesthesia (MUA), lysis of adhesions (LOA), and revision TKA in patients with chart diagnosis of keloids versus those without in patients who underwent primary TKA. Data analysis was performed using R statistical software (R Project for Statistical Computing, Vienna, Austria) utilizing multivariate logistic regression, chi square analysis, or Welch's t- test where appropriate with p values < 0.05 being considered statistically significant.

RESULTS

Of 545,875 primary TKAs, 11,461 (2.1%) had a keloid diagnosis at any time point in their record, while 534,414 (97.9%) had not. Patients in the keloid cohort had a significantly higher association with ankylosis within 30 days (OR, 1.7), 90 days (OR, 1.2), 6 months (OR, 1.2), and 1 year (OR, 1.3) following primary TKA. The keloid cohort also had a significantly greater risk of MUA (90-day OR, 1.1; 6-month OR, 1.1; 1-year OR, 1.2) and LOA (90-day OR, 2.2; 6-month OR, 2.0; 1-year OR, 1.9).

CONCLUSION

Patients with keloids have increased odds risk of arthrofibrosis following primary TKA. These patients are subsequently at a higher odds risk of undergoing the procedures necessary to treat arthrofibrosis, such as MUA and LOA. Future studies investigating confounding factors such as race, prior surgery, range of motion, and postoperative recovery are needed to confirm the association of keloid diagnosis and arthrofibrosis following primary TKA demonstrated in this study.

LEVEL OF EVIDENCE

Level III retrospective comparative study.

The role of knee arthroscopy in managing common soft tissue complications after total knee arthroplasty: a retrospective case series study

Background

To investigate the feasibility, safety and therapeutic efficacy of arthroscopy in managing the 3 most common soft tissue complications, peripatellar impingement (PI), arthrofibrosis (AF) and generalized synovitis (GS), after total knee arthroplasty (TKA).

Methods

A retrospective review of patients undertaking arthroscopy for PI, AF and GS was conducted. Outcome measures included complications, postoperative range of motion (ROM), Knee Society Score (KSS) and rates of symptom recurrence, prosthesis revision. Intraoperative findings and surgical procedures were also recorded. Paired t test, Fisher’s exact test, Kruskal-Wallis test and post hoc analysis with Bonferroni correction were used for statistical evaluation.

Results

A total of 74 patients, including 35 patients with peripatellar impingement, 25 patients with arthrofibrosis and 14 patients with generalized synovitis, with a mean age of 66.1 ± 7.9 years, were analysed. The mean follow-up (FU) duration was 81.3 ± 40.6 months. All patients underwent arthroscopic surgery safely without intraoperative complications. However, there were 4 postoperative complications, including 1 acute myocardial infarction and 3 periprosthetic joint infections. Overall, patients acquired improvements in ROM from 81.7 ± 23.1° to 96.8 ± 20.5° (p < 0.05), in KSS knee score from 64.2 ± 9.6 to 78.7 ± 12.1 (p < 0.05) and in KSS function score from 61.1 ± 7.4 to 77.3 ± 12.2 (p < 0.05) postoperatively. Patients in all 3 groups had improvements in ROM (p < 0.05), KSS knee score (p < 0.05) and KSS function score (p < 0.05). The overall recurrence rate was 22.9% (95% confidence interval (CI) 15.1–34.9%), and the overall revision rate was 14.9% (95% CI 8.6–25.6%). There were significant differences in both the symptom recurrence and prosthesis revision rates among the groups (p < 0.05). The PI group had a significantly lower symptom recurrence rate (11.4%, 95% CI 4.5–28.7%) and revision rate (8.6%, 95% CI 2.9–25.3%) (p < 0.017), while the GS group had a significantly higher recurrence rate (42.9%, 95% CI 23.4–78.5%) and revision rate (35.7%, 95% CI 17.6–72.1%) (p < 0.017).

Conclusions

In the setting of symptomatic TKA, although carrying certain risks for PJI and other complications, arthroscopic intervention could be feasible and provide clinical improvement in most cases at an average of 81.3 months follow-up. Patients with PI had the best outcomes, while patients with GS had the worst outcomes.

Level of evidence

Level IV

Knee Arthroscopy After Total Knee Arthroplasty: Not a Benign Procedure

BACKGROUND

Outcomes of knee arthroscopy (KA) after total knee arthroplasty (TKA) have been limited to small case series with short-term follow-up. The purpose of this study is to report the outcomes of patients who undergo a KA after a TKA using a large longitudinal database.

METHODS

The PearlDiver Medicare database was queried for patients who underwent a KA procedure after a TKA on the ipsilateral extremity. A randomly selected control group was created by matching controls to cases in a 3:1 ratio based on age, gender, year of procedure, and Elixhauser Comorbidity Index. Revision for infection and all-cause revision were used as end points.

RESULTS

A total of192 TKA patients who underwent a subsequent KA (TKA + KA group) were compared to 571 TKA patients who did not have a subsequent KA (TKA - KA group). The incidence of revision for infection was 6.3% in the TKA + KA group compared to 2.2% in the TKA - KA group (odds ratio, 2.87; P = .009). The incidence of all-cause revision was 18.8% in the TKA + KA group compared to 5.1% in the TKA - KA group (odds ratio, 4.34; P < .001).

CONCLUSION

KA after TKA was associated with increased infection-related and all-cause revision. The association between KA and subsequent infection requires further investigation.

Patellar Clunk Syndrome Following Posterior Stabilized Total Knee Replacement: Report of Two Cases

Patellar clunk syndrome (PCS) occasionally occurs after posterior stabilized total knee replacement (PS-TKR), and is characterized by a painful palpable audible clunk of the patella when the knee moves from flexion to extension. It has been classically attributed to the formation of fibrous nodule at the junction of the proximal pole of the patella and the undersurface of the distal quadriceps tendon. However, various intra-articular peripatellar proliferative fibrous formations have also been reported with a wide spectrum of symptoms, ranging from crepitation to frank patellar clunk. Treatment of the syndrome remains essentially surgical, and usually consists of resection of the fibrous nodules. This paper reports two cases of PCS and aims at bringing attention to this entity in terms of pathogenesis, clinical diagnosis, and treatment, through a review of the literature.

Arthroscopic Evaluation and Treatment of Complications That Arise Following Prosthetic Shoulder Arthroplasty

Arthroscopy may be used to diagnose symptomatic glenoid loosening following anatomic total shoulder arthroplasty (aTSA), and arthroscopic glenoid component removal may suffice as treatment for some patients. Arthroscopy may be used to diagnose shoulder prosthetic joint infection (PJI) following aTSA and reverse shoulder arthroplasty (RSA). Tissues are biopsied from multiple sites within the joint and the subdeltoid or subacromial space, and they are cultured for a minimum of 14 days. Postoperative adhesions arising after prosthetic shoulder arthroplasty (PSA) may be released arthroscopically. However, other problems contributing to shoulder stiffness such as component malpositioning or shoulder PJI require additional intervention. Arthroscopy may be used to repair select rotator cuff tears that arise acutely following aTSA, but chronic attritional tears do not heal after repair; therefore, revision to RSA often is needed. Many complications following PSA, such as infection, fixed instability, humeral component loosening, and major humeral or glenoid bone loss, are not adequately treated using arthroscopic techniques. However, arthroscopy following PSA may help to diagnose and treat other complications, even as the precise indications following aTSA and RSA remain unclear.

Arthroscopic Circumferential Release for Stiff Reverse Total Shoulder Arthroplasty

Stiffness is a well-known complication after reverse shoulder arthroplasty. Although multiple factors may be involved, the main cause for stiffness is rarely identified. Imaging studies frequently are inconclusive in ruling out mechanical or biological causes. Periprosthetic infection should be always suspected, but the absence of major clinical signs and accurate diagnostic tests is frequent. A lack of objective criteria establishing a diagnosis and when to proceed with revision surgery is often present in such cases. Moreover, additional surgical procedures should be carefully evaluated, as they can represent a point of no return. Shoulder arthroscopy plays an increasingly important role in these cases, either as a diagnostic or therapeutic tool. There are no reports about arthroscopy on stiffness after reverse shoulder arthroplasty. In this Technical Note, we describe an arthroscopic technique aimed to identify potential causes of reverse shoulder arthroplasty stiffness. Subsequent circumferential release is described and discussed.

Manipulation under anesthesia following total knee arthroplasty: a comprehensive review of literature

INTRODUCTION

The etiology of the stiff knee after total knee arthroplasty (TKA) is largely unknown, although excessive scar tissue due to arthrofibrosis is an important reason for a limited range of motion (ROM) after this procedure. Persistent limited ROM after TKA results in poor patient-reported outcomes and is increasingly becoming a more prominent reason for TKA revision surgery.

METHODS

A narrative review of current literature on manipulation under anesthesia (MUA) after TKA analyzing etiology and risk factors for stiffness after TKA, effectiveness of MUA and what is known about rehabilitation after MUA.

RESULTS

Literature describes numerous risk factors for insufficient knee ROM after TKA, but a comprehensive valid risk model is lacking. MUA is an effective treatment option with evidence suggesting better outcomes if performed within the first 3 months after TKA. The wide variety in both the indication and timing for MUA, and the lack of scientific evidence on how to rehabilitate patients after MUA, complicates the interpretation of available literature. This is even more so the case on the reporting of one versus two or more MUAs after TKA.

CONCLUSION

Future comparative trials, preferably with a randomized study design, should be conducted to elude more clear indications for MUA, to give clinical guidance on correct timing for MUA and on how to rehabilitate patients afterward.

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.

Efficacy of Revision Surgery for the Treatment of Stiffness After Total Knee Arthroplasty: A Systematic Review

BACKGROUND

Knee stiffness following total knee arthroplasty (TKA) may cause pain and reduced functionality, contributing to unsatisfactory surgical outcomes. Revision surgery remains a possible treatment for refractory postoperative stiffness. However, the efficacy of the procedure has not been systematically evaluated.

METHODS

A systematic review of the literature was performed to identify studies that reported on outcomes for patients who underwent revision surgery for postoperative stiffness after TKA.

RESULTS

Ten studies (including 485 knees) were reviewed. The most common etiologies of stiffness requiring revision TKA were component malposition, malalignment, overstuffing, aseptic loosening, arthrofibrosis, patella baja, and heterotopic ossification. Of 9 studies reviewing range of motion outcomes after revision TKA, 7 studies documented significant improvement and 2 found trends toward improvement. Seven of 8 studies documenting Knee Society knee scores and 7 of 9 studies documenting functional scores found improvement after revision TKA. All studies reporting on pain found improvement at final follow-up after revision TKA.

CONCLUSION

Revision TKA results in increased range of motion, improved functionality, and reduced pain in most patients who require surgery for stiffness. The present literature is inadequate to predict which patients will achieve adequate outcomes from revision TKA based on the specific etiology of their stiffness, although identification of the etiology may help in surgical planning. Surgeons performing revision TKA should counsel patients on the risks and benefits of undergoing revision surgery, with the understanding that outcomes for well-selected patients are generally favorable.

Prognostic factors that predict failure of manipulation under anesthesia for the stiff total knee arthroplasty: A systematic review

Purpose

Prognostic factors associated with Manipulation under anesthesia (MUA) failure remain unknown.

Methods

A systematic review of the literature was performed to identify studies that reported prognostic factors associated with MUA for postoperative stiffness.

Results

7 studies analyzing prognostic factors associated with MUA outcomes were included. Several studies note pre-MUA ROM to be a significant prognostic factor affecting post-MUA ROM at final follow-up. Knees with <70° of flexion pre-MUA had less final flexion arc than those with >70°.

Conclusions

The strongest prognostic factor for decreased ROM after MUA is severe pre-MUA stiffness.

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.

Intraarticular arthrofibrosis of the knee alters patellofemoral contact biomechanics

BACKGROUND

Arthrofibrosis in the suprapatellar pouch and anterior interval can develop after knee injury or surgery, resulting in anterior knee pain. These adhesions have not been biomechanically characterized.

METHODS

The biomechanical effects of adhesions in the suprapatellar pouch and anterior interval during simulated quadriceps muscle contraction from 0 to 90° of knee flexion were assessed. Adhesions of the suprapatellar pouch and anterior interval were hypothesized to alter the patellofemoral contact biomechanics and increase the patellofemoral contact force compared to no adhesions.

RESULTS

Across all flexion angles, suprapatellar adhesions increased the patellofemoral contact force compared to no adhesions by a mean of 80 N. Similarly, anterior interval adhesions increased the contact force by a mean of 36 N. Combined suprapatellar and anterior interval adhesions increased the mean patellofemoral contact force by 120 N. Suprapatellar adhesions resulted in a proximally translated patella from 0 to 60°, and anterior interval adhesions resulted in a distally translated patella at all flexion angles other than 15° (p < 0.05).

CONCLUSIONS

The most important finding in this study was that patellofemoral contact forces were significantly increased by simulated adhesions in the suprapatellar pouch and anterior interval. Anterior knee pain and osteoarthritis may result from an increase in patellofemoral contact force due to patellar and quadriceps tendon adhesions. For these patients, arthroscopic lysis of adhesions may be beneficial.

Outcomes and Predictors of Success for Arthroscopic Lysis of Adhesions for the Stiff Total Knee Arthroplasty

A stiff total knee arthroplasty (TKA) can manifest as pain and decreased range of motion (ROM). When conservative management including physical therapy and manipulation under anesthesia fails, arthroscopic lysis of adhesions (LOA) is frequently pursued. The authors examined the efficacy of LOA for the stiff TKA. They retrospectively reviewed the records of 18 patients who underwent LOA for stiff TKA between April 2013 and June 2016 and who failed to meet 90° ROM at 6 weeks postoperatively. They recorded patient demographics, ROM prior to TKA, and incidence of manipulation under anesthesia between initial TKA and LOA as well as pre- and postoperative outcomes of ROM, pain, and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores. The mean time from TKA to LOA was 117 days, with a mean follow-up of 449 days. Mean improvements in ROM flexion contracture, flexion, and arc were 6.11° (P<.05), 29.45° (P<.001), and 35.56° (P<.001), respectively. Range of motion improved for 17 of 18 patients. The WOMAC was completed by 15 of 18 patients, with a mean improvement in scores of 32.23% (P<.001); all 15 patients with available WOMAC scores improved. Pain score improved by a mean of 2.17 (P<.001), with 14 of 18 patients reporting decreased pain. Improvements in flexion contracture, flexion, ROM arc, WOMAC scores, and pain were all statistically significant (P<.05). Age, weight, body mass index, and time to LOA were found to be statistically significant predictors of outcome. Finally, pre-TKA and pre-LOA ROM parameters were found to be statistically significant predictors of post-LOA ROM outcomes. [Orthopedics. 2017; 40(6):e1062-e1068.].

Painful Knee is not Uncommon after total Knee Arthroplasty and can be Treated by Arthroscopic Debridement

Background

After total knee arthroplasty (TKA), most patients have an improvement; however, a few continue to have residual pain. We reported a case series of painful knee after TKA with unreported reason.

Material and Methods

Forty-six arthroscopic surgeries were performed for painful knee after TKA. Of these, 16 were excluded due to infection, patellar clunk syndrome, patellofemoral synovial hyperplasia, aseptic loosening, or short follow up less than 6 months. Remaining 30 cases had marked tenderness at the medial and/or lateral tibiofemoral joint space, and they had pain during walking with pain or without pain at rest. The mean period from initial TKA to arthroscopy was 29 months, and the mean follow-up after arthroscopy was 36 months. All arthroscopic debridement was performed through 3 portals. Scar tissue impingements graded moderate or severe were found only in 30% of the cases in both the medial and lateral tibiofemoral joint spaces. The infrapatellar fat pad was covered with whitish scar tissue in all cases, and the tissue was connected with the scar tissue at the medial or lateral tibiofemoral joint spaces. All scar tissue was removed with a motorized shaver or punches.

Results

At the final follow-up, 63% were pain free, 3% had marked improvement, 20% had half improvement, 3% had slight improvement, and 11% had no change. We hypothesized that the lesser mobility of the scar tissue due to the continuity of the tissue between the infrapatellar fat pad and the tibiofemoral joint space could cause easy impingement at the tibiofemoral joint, even with the small volume of scar tissue.

Conclusion

If infection and aseptic loosening could be ruled out in a painful knee after TKA, arthroscopic debridement appeared to be a good option to resolve the pain.

Comparative Clinical Observation of Arthroscopic Microfracture in the Presence and Absence of a Stromal Vascular Fraction Injection for Osteoarthritis

Osteoarthritis (OA) is a degenerative cartilage disease that is characterized by a local inflammatory reaction. Consequently, many studies have been performed to identify suitable prevention and treatment interventions. In recent years, both arthroscopic microfracture (AM) and stem cell therapy have been used clinically to treat OA. This study aimed to evaluate the clinical effects of AM in the presence and absence of a stromal vascular fraction (SVF) injection in the management of patients with OA. Thirty patients with grade 2 or 3 (Lawrence scale) OA of the knee participated in this study. Placebo group patients (n = 15) received AM alone; treatment group patients (n = 15) received AM and an adipose tissue‐derived SVF injection. The SVF was suspended in platelet‐rich plasma (PRP) before injection into the joint. Patient groups were monitored and scored with the Western Ontario and McMaster Universities Arthritis Index (WOMAC), Lysholm, Visual Analog Pain Scale (VAS), and modified Outerbridge classifications before treatment and at 6, 12, and 18 months post‐treatment. Bone marrow edema was also assessed at these time points. Patients were evaluated for knee activity (joint motion amplitude) and adverse effects relating to surgery and stem cell injection. Treatment efficacy was significantly different between placebo and treatment groups. All treatment group patients had significantly reduced pain and WOMAC scores, and increased Lysholm and VAS scores compared with the placebo group. These findings suggest that the SVF/PRP injection efficiently improved OA for 18 months after treatment. This study will be continuously monitored for additional 24 months. Stem Cells Translational Medicine2017;6:187–195

Indications and outcomes of shoulder arthroscopy after shoulder arthroplasty

BACKGROUND

Arthroscopy is a widely used intervention in the treatment of a variety of shoulder conditions. Arthroscopy has also been selectively used in symptomatic patients after shoulder arthroplasty. The purpose of this systematic review was to determine indications for shoulder arthroscopy in patients after shoulder arthroplasty and to report patient outcomes after these procedures.

MATERIALS AND METHODS

The electronic databases MEDLINE, EMBASE, and PubMed were searched and screened in duplicate for studies involving shoulder arthroscopy in shoulder arthroplasty patients. A full-text review of eligible studies was conducted in duplicate, and references were searched using predetermined inclusion and exclusion criteria.

RESULTS

The review included 11 studies containing 84 patients. All were Level IV evidence. The most common indications for shoulder arthroscopy in the setting of shoulder arthroplasty were pain or loss of range of motion without a clear diagnosis, suspected periprosthetic infection, and rotator cuff assessment. Although 92% of patients were satisfied with the procedure and standardized shoulder scores increased in all studies that reported them, 44% of patients still went on to additional revision surgery after arthroscopy.

CONCLUSIONS

Shoulder arthroscopy in patients after arthroplasty is most frequently used as a diagnostic tool; however, it has utility in treating a number of predetermined pathologies. Despite the low sample size and quality of evidence in our review, patient satisfaction after arthroscopy is high because standardized outcome scores improve, and the risk of complications is low. However, a high percentage of patients who receive arthroscopy later require further surgery.

Safety and efficacy of arthroscopy in the setting of shoulder arthroplasty

Shoulder arthroplasty has become a reliable and reproducible method of treating a range of shoulder pathologies including fractures, osteoarthritis, and rotator cuff arthropathy. Although most patients experience favorable outcomes from shoulder arthroplasty, some patients suffer from persistent symptoms post-arthroplasty and it is these patients who present a unique diagnostic and therapeutic challenge. The role of arthroscopy in assessing and treating patients with symptomatic prosthetic joints elsewhere in the body has been established in recent literature. However, the range of pathology that can affect a prosthetic shoulder is distinct from the knee or the hip and requires careful and considered assessment if an accurate diagnosis is to be made. When used alongside other investigations in a comprehensive assessment protocol, arthroscopy can play an important role in the diagnosis and treatment of the problematic shoulder arthroplasty.

Hip arthroscopy in the setting of hip arthroplasty

PURPOSE

Hip arthroscopy has traditionally been viewed as a hip preservation procedure performed in patients with native joint pathology. However, as the list of indications for arthroscopic hip intervention grows, further advances are expanding its use. The purpose of this systematic review was to examine existing evidence supporting the use of hip arthroscopy in the setting of hip arthroplasty.

METHODS

Using predetermined inclusion criteria, EMBASE, MEDLINE and PubMed were searched for articles addressing arthroscopic hip surgery performed in hips containing joint replacement arthroplasties. Inclusion criteria limited our search to human and English language studies addressing articles where clear surgical indications are described. Article screening was conducted in duplicate.

RESULTS

Seven-hundred and forty-three studies were retrieved before duplicate screening, and 18 satisfied inclusion criteria. Eleven case series, six case reports and one prospective cohort study are included. In total, 171 patients underwent hip arthroscopy following previous arthroplasty. Indications for arthroscopy included iliopsoas tendinopathy (35.8%), symptomatic hips with no clear diagnosis despite extensive investigation (24.6%), periprosthetic infection (6.4%) and intra-articular loose bodies (3.5%). Almost all patients who underwent hip arthroscopy experienced positive outcomes from the procedure.

CONCLUSION

Hip arthroscopy after hip arthroplasty is supported by our systematic review for a variety of indications. Hip arthroscopy can be a safe and effective method of treating hip arthroplasty patients with iliopsoas tendinopathy. Hip arthroscopy also has utility in patients with symptomatic hip arthroplasty despite exhaustion of other diagnostic avenues.

LEVEL OF EVIDENCE

A systematic review of level IV studies.

Arthroscopic Management of Popliteal Tendon Dysfunction in Total Knee Arthroplasty

Unexplainable knee pain may follow knee replacement surgery. The popliteal tendon should be evaluated as a possible cause of lateral knee pain and dysfunction after knee arthroplasty. The tendon can snap over or impinge on lateral osteophytes or prominent femoral components and produce mechanical symptoms and pain. Ultrasound-guided injections may confirm the diagnosis and provide symptomatic relief in some patients. Those who respond well to injections and in whom conservative management ultimately fails may be offered arthroscopic release of the popliteal tendon. We present the arthroscopic technique for popliteal tendon release in a symptomatic patient whose pain resolved immediately postoperatively. We recommend the use of an anterolateral viewing portal and an accessory lateral working portal to access the posterolateral knee. There can be extensive scar tissue overlying the popliteal tendon after arthroplasty. Arthroscopic tendon transection and excision comprise a reliable procedure for popliteal tendon impingement after knee arthroplasty without compromising knee stability.

Persistent Symptomatic Knee after Total Knee Replacement. Is Knee Arthroscopy Helpful?

Persistent symptoms following total knee replacement (TKR) could be diagnostically challenging. We present three cases of knee arthroscopy following TKR to illustrate the effectiveness of arthroscopy for the diagnosis and treatment of persistent symptomatic knee. It is concluded that arthroscopy after TKR is a relatively safe and effective procedure for well selected cases with persistent symptoms following TKR.

Arthroscopic lysis of adhesions for the stiff total knee arthroplasty

The management of the stiff knee after total knee arthroplasty is controversial. Manipulation under anesthesia and open lysis of adhesions are techniques that can theoretically address the fibrous scar tissue, but their efficacy has been shown to be variable. We describe the technique of arthroscopic lysis of adhesions for the stiff knee after total knee arthroplasty. The advantages of this technique include minimally invasive debridement of scar tissue within defined compartments of the knee and evaluation for the presence and treatment of focal lesions (e.g., loose bodies or impinging synovial or soft tissue). The total arc of motion can be improved with a systematic arthroscopic approach.

Incidence of patellar clunk syndrome in fixed versus high-flex mobile bearing posterior-stabilized total knee arthroplasty

The geometry of the intercondylar box plays a significant role in the development of patellar clunk syndrome. We reviewed the incidence of patella clunk at mid-to-long-term follow-up of a rotating high-flex versus fixed bearing posterior stabilized TKA design. 188-mobile and 223-fixed bearing TKAs were reviewed for complications, incidence of patellar clunk, treatment, recurrence rates, range of motion, and patient satisfaction. Patellar clunk developed in 22 knees in the mobile (11.7%) and in 4 (1.8%) in the fixed bearing group (P<0.001). 23 out of 26 cases resolved with a single arthroscopic treatment and 2 resolved with a second procedure. The mean postoperative range of motion was 122.4°. All but one patient reported overall satisfaction with the index procedure. In contrast with other recent studies we found a significant incidence of patellar clunk in high-flex mobile bearings. Despite the high rate of patellar clunk syndrome, overall patients did well and were satisfied with their outcomes.

Risk factors for manipulation after total knee arthroplasty: a pooled electronic health record database study

A commercially available software platform, Explorys (Explorys, Inc., Cleveland, OH), was used to mine a pooled electronic healthcare database consisting of the medical records of more than 27 million patients. A total of 229,420 patients had undergone a total knee arthroplasty; 3470 (1.51%) patients were identified to have undergone manipulation under anesthesia. Individual risk factors of being female, African American race, age less than 60, BMI >30 and nicotine dependence were determined to have relative risk of 1.25, 2.20, 3.46, 1.33 and 1.32 respectively. Depressive disorder, diabetes mellitus, opioid abuse/dependence and rheumatoid arthritis were not significant risk factors. African Americans under the age of 60 at time of TKA had the greatest incidence of MUA (5.17%) and relative risk of 3.73 (CI: 3.36, 4.13).

Patellar clunk syndrome after total knee arthroplasty; risk factors and functional outcomes of arthroscopic treatment

This study reports the incidence, risk factors, and functional outcomes of the largest reported series of patients treated arthroscopically for patella clunk syndrome (PCS). All patients treated arthroscopically for PCS were identified. Patients were matched with controls by sex and date of surgery. Follow-up was conducted using SF-12 and WOMAC questionnaires. Operative notes and preoperative and postoperative radiographs were reviewed. Seventy-five knees in 68 patients were treated arthroscopically for PCS. Average follow-up was 4.2 years. Functional scores demonstrated no statistical difference. PCS patients had a significantly more valgus preoperative alignment, greater change in posterior femoral offset and smaller patellar component size. PCS is a relatively common complication following TKA. Arthroscopy yields functional results comparable to controls. Radiographic and technical factors are associated with PCS.

Arthroscopic lysis of adhesions for the stiff total knee: results after failed manipulation

Arthrofibrosis after total knee arthroplasty (TKA) is a potentially devastating complication, resulting in loss of motion and function and residual pain. For patients in whom aggressive physical therapy and manipulation under anesthesia fail, lysis of adhesions may be the only option to rescue the stiff TKA. The purpose of this study is to report the results of arthroscopic lysis of adhesions after failed manipulation for a stiff, cruciate-substituting TKA. This retrospective study evaluated patients who had undergone arthroscopic lysis of adhesions for arthrofibrosis after TKA between 2007 and 2011. Minimum follow-up was 12 months (average, 31 months). Average total range of motion of patients in this series was 62.3°. Average preoperative flexion contracture was 16° and average flexion was 78.6°. Statistical analysis was performed using Student's t test. Pre- to postoperative increase in range of motion was significant (P<.001) (average, 62° preoperatively to 98° postoperatively). Average preoperative extension deficit was 16°, which was reduced to 4° at final follow-up. This value was also found to be statistically significant (P<.0001). With regard to ultimate flexion attained, average preoperative flexion was 79°, which was improved to 103° at final follow-up. This improvement in flexion was statistically significant (P<.0001). Patients can reliably expect an improvement after arthroscopic lysis of adhesions for a stiff TKA using a standardized arthroscopic approach; however, patients achieved approximately half of the improvement that was obtained at the time of surgery.

Arthroscopic lysis of adhesions for stiff total knee arthroplasty

The goal of this study was to evaluate the efficacy of arthroscopic lysis of adhesions after total knee arthroplasty (TKA) in improving range of motion (ROM) and providing an improvement in knee function. The authors retrospectively examined 19 patients who underwent arthroscopic lysis of adhesions following TKA due to poor ROM. The criterion for lysis was the inability to flex to 90° at 3 months. All patients were followed for at least 2 years after lysis. Patient demographics, postoperative and follow-up ROM,number of prior surgeries, Knee Society Scores, and Western Ontario and McMaster Universities Arthritis Index (WOMAC) functional scores were collected. Average ROM increased from 75.37° preoperatively to 98.95° postoperatively. The authors found an association between preoperative knee score and change in ROM between pre-arthroscopic lysis and ROM at final follow-up (P=.0188). When the authors examined the relationship between patient body mass index (BMI) and change in ROM,they found that patients with a BMI higher than 30 kg/m2 had a change of 26.44° compared with patients with a BMI lower than 30 kg/m2, who had a change of only 8.75°. A strong association was found between patient height and change in ROM and final ROM achieved (P=.0062 and .0032, respectively). The authors report a successful outcome among study patients. Furthermore, they found an association between patient height, BMI, and preoperative knee score and the improvement achieved after arthroscopic lysis of adhesions following TKA. The current study's results are comparable with those of published results. The authors recommend arthroscopic lysis of adhesions as a treatment option for stiff knees after TKA that fails after at least 3 months of nonoperative treatment.

Arthroscopic reduction of a chronically dislocated reversed shoulder arthroplasty

We present the case of a 64-year-old female patient who had a traumatic dislocation of a reversed shoulder arthroplasty that was unnoticed for 5 weeks and that was reduced arthroscopically. Arthroscopy of the shoulder, as in other joints with prostheses, can facilitate the treatment of conditions that would otherwise require the use of open surgery to solve them and that might become more frequent because of the widespread use of reversed shoulder arthroplasties, which have a high rate of dislocation.

Painful patellar clunk or crepitation of contemporary knee prostheses

BACKGROUND

Painful patellar clunk or crepitation (PCC) is a resurgent complication of contemporary posterior-stabilized TKA. The incidence, time to presentation, causes, and treatment of PCC still remain controversial.

QUESTIONS/PURPOSES

We therefore (1) compared the incidence of PCC with five contemporary TKA designs, (2) evaluated the time to presentation, (3) identified possible etiologies, and (4) determined recurrence rate and change in knee functional scores after treatment for PCC.

METHODS

We reviewed 580 patients who had 826 posterior-stabilized TKAs involving five different designs. The incidences of PCC were compared among the prostheses. The knees were divided into two groups depending on the development of PCC, and possible etiologic factors of PCC, including prosthesis design and surgical or radiographic variables, were compared between groups. We investigated the onset time of PCC and evaluated treatment results by knee outcome scores. Minimum followup was 2.0 years (mean, 3.9 years; range, 2.0-9.8 years).

RESULTS

The PCC incidence was higher in the Press-Fit Condylar(®) Sigma(®) Rotating Platform/Rotating Platform-Flex Knee System (11 of 113 knees, 9.7%) than in the others (seven of 713 knees, 1.0%). Increased risk of PCC was associated with using a specific prosthesis and patellar retention. PCC occurred in all cases within a year after TKA (mean, 7.4 months). Arthroscopic treatment (16 knees) and patellar replacement (two knees) improved knee scores, with no recurrence observed over an average followup of 29 months.

CONCLUSIONS

Prosthesis design and patellar retention were associated with PCC. Surgery resolved the PCC.

Is further treatment necessary for patellar crepitus after total knee arthroplasty?

BACKGROUND

Patellar crepitus may occur with posterior-stabilized (PS) TKAs. Several studies have suggested numerous etiologies of patellar crepitus after PS-TKA with patellar resurfacing. However, it is unclear whether and to what degree crepitus influences pain and function without or with patellar resurfacing.

QUESTIONS/PURPOSES

We therefore determined (1) the frequency of crepitus; (2) which factors predicted the occurrence of crepitus; and (3) whether crepitus influenced pain and function.

METHODS

We retrospectively reviewed 41 patients (54 knees) with painful or painless patellar crepitus after primary PS-TKAs without patellar resurfacing performed from 2007 to 2008. These patients were compared with a group of 73 patients (94 knees) without patellar crepitus matched for age, sex, and BMI. The minimum followup was 2 years (mean, 2.8 years; range, 2-4.5 years).

RESULTS

Five (9%) of the 54 knees with patellar crepitus also had peripatellar pain. Mean time from primary TKA to the onset of patellar crepitus was 4 months. All patients in the patellar crepitus group were asymptomatic within 1 year of onset of symptoms without additional surgical treatment. The development of patellar crepitus was associated with an Outerbridge patellar cartilage Grade 4 (odds ratio [OR], 11.9; 95% CI, 2.2-65.3) and joint line elevation (OR, 5.1; 95% CI, 1.9-8.6).

CONCLUSIONS

Patellar crepitus is typically benign and self-limited. We continue not to resurface arthritic patellae and counsel patients with patellar crepitus that their symptoms will improve without intervention.

LEVEL OF EVIDENCE

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

Management of stiffness following total knee arthroplasty: a systematic review

AIM

The aim of the study was to systematically evaluate the outcome of four main modalities of treatment for arthrofibrosis that develops subsequent to a total knee arthroplasty (TKA), namely manipulation under anesthesia (MUA), arthroscopic debridement, open surgical release and revision TKA.

MATERIALS AND METHODS

A computerised search was conducted for relevant studies published from 1975 onwards in all the major databases and various search engines. A total of twenty-five studies were selected, representing a total of 798 patients. Studies that passed the inclusion criteria were then subjected to quality assessment using the Newcastle-Ottawa Scale. On assessment, the 25 studies scored a total of 77 stars out of a possible 125. Two studies were prospective in design, while the remaining case series were retrospective in nature. The primary outcome measures assessed were increase in range of movement (ROM) and the Knee Society Score (KSS) at final follow-up.

RESULTS

Our results showed that manipulation under anesthesia (MUA) had a mean increase in ROM of 38.4°, arthroscopic release had a mean increase of 36.2°, open surgical release had a mean increase of 43.4° and revision TKA had a mean increase of 24.7°. No significant differences were found in the KSS of the four treatment modalities. Our analysis suggests that open surgical release would be the most beneficial option for patients who are fit to undergo secondary surgery if their lifestyle requires a higher ROM for activities of daily living. However, there were methodological limitations as majority of the papers were case series, which decreased the quality of the evidence available.

A Comparison of the Clinical and Radiographic Results of Press Fit Condylar Rotating-Platform High-Flexion and Low Contact Stress Mobile Bearing Prosthesis in Total Knee Arthroplasty: Short term Results

Purpose

This study compared the results of rotating-platform high-flexion (RP-F) total knee arthroplasty with low contact stress (LCS) for clinical and radiographical assessment after a short-term period.

Materials and Methods

68 total knee arthroplasties using a RP-F and LCS system were analyzed retrospectively. Thirty-five of the 68 were osteoarthritic knees and were followed-up for more than 2 years. The clinical evaluation included range of motion (ROM), Knee Society Knee Score and Function Score (KSKS and KSFS), tailor position and kneeling. The radiographic evaluation included femorotibial angle, position of implants, radiolucent line and position of patella.

Results

The postoperative ROM, KSKS, and KSFS improved statistically in both implants. Comparing RP-F with LCS there were statistically no differences in ROM (p=0.863), KSKS (p=0.835), KSFS (p=0.535) and tailor position (p=0.489). There were no significant radiographic differences.

Conclusions

Total knee arthroplasty with RP-F and LCS showed similar clinical and radiographic results; it also showed excellent and predictable results at the short-term follow up. However, in RP-F there was 1 case of early osteolysis, 1 case of patella clunk syndrome and 1 case of painful patella crepitus; therefore, further case studies and follow-up are needed.

Meniscal Regeneration: A Cause of Persisting Pain following Total Knee Arthroplasty

Many patients have persisting knee pain following total knee arthroplasty. We report the unusual case of a patient whose chronic lateral and medial knee pain were caused by entrapped regenerated meniscal tissue. This was diagnosed and successfully treated by arthroscopic debridement.

Causes of failure and etiology of painful primary total knee arthroplasty

The review provides an overview of the causes of failure and the many different aetiologies of a painful primary total knee arthroplasty (TKA). They can be classified into extra- and intraarticular disorders, the latter being divided into biological and mechanical origins. Whereas biological aetiologies like infections have remained stable over time, other causes of failure have changed. In the early times of knee arthroplasty, they were mainly related to technical insufficiencies. A better understanding of knee arthroplasty, patients' increasing functional demands as well as a continuous development of TKA techniques generated newer problems, which are increasingly related to the functioning of the soft-tissue envelope of the knee. From a therapeutic point of view, three situations can be considered: functional problems not needing reoperations, causes of reoperations not needing an exchange of prosthetic components as well as reoperations with exchange of at least one prosthetic component.

Arthroscopic arthrolysis for arthrofibrosis of the knee after total knee replacement

BACKGROUND

Arthrofibrosis is an uncommon but potentially debilitating complication following total knee replacement which can result in chronic pain and poor recovery of range of motion. The treatment of this condition remains difficult and controversial. QUESTIONS/AIMS OF STUDY: We reviewed our results of arthroscopic arthrolysis of arthrofibrosis of the knee after total knee replacement to assess the potential for this technique to improve range of motion and provide improvement in knee function and pain as measured by the Knee Society Score (KSS).

METHODS

Eight patients were treated for arthrofibrosis after total knee replacement with arthroscopic management. The patients included five females and three males. The average age was 67.4 years. Initial rehabilitation efforts, which included manipulation under anesthesia, had failed. Arthroscopic arthrolysis was performed to release fibrous bands in the suprapatellar pouch and to reestablish the medial and lateral gutters. Lateral release of the patellar retinaculum was performed. Intensive physiotherapy and continuous passive motion began immediately post-operatively. The average follow-up was 37.4 months. The KSS was used for assessment of pain and function before arthroscopy and at the latest follow-up.

RESULTS

Six of the eight patients experienced improvement in the KSS. The average functional score showed improvement from 68 points pre-operatively to 86 at the time of final follow-up. The average pain scores improved from 30 points pre-operatively to 41 at the time of final follow-up.

CONCLUSIONS

Arthroscopic management can be beneficial for patients suffering from arthrofibrosis following total knee replacement. Pain and KSS clinical scores can markedly improve.

Stiffness after TKR: how to avoid repeat surgery

Stiffness after total knee replacement (TKR) is a frustrating complication that has many possible causes. Although the definition of stiffness has changed over the years, most would agree that flexion <75° and a 15° lack of extension constitutes stiffness. The management of this potentially unsatisfying situation begins preoperatively with guidance of the patient's expectations; it is well-known that preoperative stiffness is strongly correlated with postoperative lack of motion. At the time of surgery, osteophytes must be removed and the components properly sized and aligned and rotated. Soft tissue balancing must be attained in both the flexion/extension and varus/valgus planes. One must avoid overstuffing the tibiofemoral and/or patellofemoral compartments with an inadequate bone resection. Despite these surgical measures and adequate pain control and rehabilitation, certain patients will continue to frustrate our best efforts. These patients likely have a biological predisposition for formation of scar tissue. Other potential causes for the stiff TKR include complex regional pain syndrome or joint infection. Close follow-up of a patient's progress is crucial for the success in return of range of motion. Should motion plateau early in the recovery phase, the patient should be evaluated for manipulation under anesthesia. The results of reoperations for a stiff TKR are variable due to the multiple etiologies. A clear cause of stiffness such as component malposition, malrotation, or overstuffing of the joint has a greater chance of regaining motion than arthrofibrosis without a clear cause. Although surgical treatment with open arthrolysis, isolated component, or complete revision can be used to improve TKR motion, results have been variable and additional procedures are often necessary.

Mast cells and hypoxia drive tissue metaplasia and heterotopic ossification in idiopathic arthrofibrosis after total knee arthroplasty

BACKGROUND

Idiopathic arthrofibrosis occurs in 3-4% of patients who undergo total knee arthroplasty (TKA). However, little is known about the cellular or molecular changes involved in the onset or progression of this condition. To classify the histomorphologic changes and evaluate potential contributing factors, periarticular tissues from the knees of patients with arthrofibrosis were analyzed for fibroblast and mast cell proliferation, heterotopic ossification, cellular apoptosis, hypoxia and oxidative stress.

RESULTS

The arthrofibrotic tissue was composed of dense fibroblastic regions, with limited vascularity along the outer edges. Within the fibrotic regions, elevated numbers of chymase/fibroblast growth factor (FGF)-expressing mast cells were observed. In addition, this region contained fibrocartilage and associated heterotopic ossification, which quantitatively correlated with decreased range of motion (stiffness). Fibrotic, fibrocartilage and ossified regions contained few terminal dUTP nick end labeling (TUNEL)-positive or apoptotic cells, despite positive immunostaining for lactate dehydrogenase (LDH)5, a marker of hypoxia, and nitrotyrosine, a marker for protein nitrosylation. LDH5 and nitrotyrosine were found in the same tissue areas, indicating that hypoxic areas within the tissue were associated with increased production of reactive oxygen and nitrogen species.

CONCLUSIONS

Taken together, we suggest that hypoxia-associated oxidative stress initiates mast cell proliferation and FGF secretion, spurring fibroblast proliferation and tissue fibrosis. Fibroblasts within this hypoxic environment undergo metaplastic transformation to fibrocartilage, followed by heterotopic ossification, resulting in increased joint stiffness. Thus, hypoxia and associated oxidative stress are potential therapeutic targets for fibrosis and metaplastic progression of idiopathic arthrofibrosis after TKA.

Revision total knee arthroplasty for stiffness

Few studies have evaluated the results of revision of well-fixed components for stiffness, and some authors have recommended against this intervention based on poor reported results. Thirty-five consecutive patients underwent revision of both femoral and tibial components for stiffness. At a mean of 54.5 months (range, 25-134), the mean arc of motion improved by 44.5 degrees from a preoperative mean of 53.6 degrees to a postoperative mean of 98.1 degrees (P < .0001). The arc of motion improved by more than 30 degrees in 75% (24/32) of patients evaluated at a minimum of 2 years. Seventeen (49%) of the 35 patients required a further intervention for stiffness or sustained a complication. These results suggest that revision total knee arthroplasty for stiffness can be performed with a reasonable expectation of improvement, although the risk of complications and additional operative procedures is substantial.

How to treat the stiff total knee arthroplasty?: a systematic review

BACKGROUND

Multiple modalities have been used to treat the stiff TKA, including manipulation under anesthesia (MUA), arthroscopy, and open arthrolysis.

QUESTIONS/PURPOSES

We reviewed the literature to address three questions: (1) How many degrees of ROM will a stiff TKA gain after MUA, arthroscopy, and open arthrolysis? (2) Does the timing of each procedure influence this gain in ROM? (3) What is the number of clinically important complications for each procedure?

METHODS

We performed a PubMed search of English language articles from 1966 to 2008 and identified 20 articles, mostly Level IV studies.

RESULTS

For patients who have arthrofibrosis after TKA, the gains in ROM after MUA and arthroscopy (with or without MUA) are similar. Open arthrolysis seems to have inferior gains in ROM. MUA is more successful in increasing ROM when performed early but still may be effective when performed late. Arthroscopy combined with MUA still is useful 1 year after the index TKA. The numbers of clinically important complications after MUA and arthroscopy (with or without MUA) are similar.

CONCLUSIONS

Stiffness after TKA is a common problem that can be improved with MUA and/or arthroscopic lysis of adhesions with few complications. The low quality of available literature makes it difficult to develop treatment protocols.

LEVEL OF EVIDENCE

Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Arthroscopic arthrolysis for the treatment of stiffness after total knee replacement gives moderate improvements in range of motion and functional knee scores

Twenty-two total knee replacements (TKR's) were treated for stiffness with arthroscopy and arthrolysis. The median follow-up was 38 months. No patients were lost to follow up. Extensive scarring was found and debrided in all of the knees. The mean Oxford Knee Score improved from 42.6 (+/-7.5) to 36.3 (+/-8.5) (P < 0.05) with TKR and from 36.3 (+/-8.5) to 29.3 (+/-9.0) (P < 0.05) with arthroscopic arthrolysis. The mean arc of motion improved from 8-69 degrees post-TKR to 3-105 degrees on table, but declined slightly to 4-93 degrees (P < 0.05) at most recent review. Arthroscopic arthrolysis compares well with other methods of treatment for stiffness with regard to improvements in range of motion and functional knee scores.

Arthroscopic treatment of patellar clunk and synovial hyperplasia after total knee arthroplasty

Patellofemoral pain, crepitus, and locking are infrequent symptoms after total knee arthroplasty (TKA). We performed a retrospective review of 25 patients who underwent arthroscopic debridement after primary TKA to treat the patellar clunk syndrome (15 knees) or patellofemoral synovial hyperplasia (10 knees). After surgery, patient-reported knee pain and crepitus as well as Knee Society knee and function scores improved in both groups. Postoperative knee range of motion remained unchanged. Arthroscopic debridement of symptomatic patellofemoral synovium after TKA is a safe and effective procedure.

Reactive oxygen and nitrogen species induce protein and DNA modifications driving arthrofibrosis following total knee arthroplasty

Background

Arthrofibrosis, occurring in 3%-4% of patients following total knee arthroplasty (TKA), is a challenging condition for which there is no defined cause. The hypothesis for this study was that disregulated production of reactive oxygen species (ROS) and nitrogen species (RNS) mediates matrix protein and DNA modifications, which result in excessive fibroblastic proliferation.

Results

We found increased numbers of macrophages and lymphocytes, along with elevated amounts of myeloperoxidase (MPO) in arthrofibrotic tissues when compared to control tissues. MPO expression, an enzyme that generates ROS/RNS, is usually limited to neutrophils and some macrophages, but was found by immunohistochemistry to be expressed in both macrophages and fibroblasts in arthrofibrotic tissue. As direct measurement of ROS/RNS is not feasible, products including DNA hydroxylation (8-OHdG), and protein nitrosylation (nitrotyrosine) were measured by immunohistochemistry. Quantification of the staining showed that 8-OHdg was significantly increased in arthrofibrotic tissue. There was also a direct correlation between the intensity of inflammation and ROS/RNS to the amount of heterotopic ossification (HO). In order to investigate the aberrant expression of MPO, a real-time oxidative stress polymerase chain reaction array was performed on fibroblasts isolated from arthrofibrotic and control tissues. The results of this array confirmed the upregulation of MPO expression in arthrofibrotic fibroblasts and highlighted the downregulated expression of the antioxidants, superoxide dismutase1 and microsomal glutathione S-transferase 3, as well as the significant increase in thioredoxin reductase, a known promoter of cell proliferation, and polynucleotide kinase 3'-phosphatase, a key enzyme in the base excision repair pathway for oxidative DNA damage.

Conclusion

Based on our current findings, we suggest that ROS/RNS initiate and sustain the arthrofibrotic response driving aggressive fibroblast proliferation and subsequent HO.