Associations amongst dynamic knee stiffness during gait, quadriceps stiffness, and the incidence of knee osteoarthritis over 24 months: a cohort study with a mediation analysis.

BACKGROUND: Decreased strength and increased stiffness of the quadriceps have been associated with a higher risk of developing knee osteoarthritis (OA) in elders. Dynamic joint stiffness (DJS) represents collective resistance from active and passive knee structures for dynamic knee motions. Elevated sagittal knee DJS has been associated with worsening of cartilage loss in knee OA patients. Altered quadriceps properties may affect DJS, which could be a mediator for associations between quadriceps properties and knee OA. Hence, this study aimed to examine whether DJS and quadriceps properties would be associated with the development of clinical knee OA over 24 months, and to explore the mediation role of DJS in associations between quadriceps properties and knee OA. METHODS: This was a prospective cohort study with 162 healthy community-dwelling elders. Gait analysis was conducted to compute DJS during the loading response phase. Quadriceps strength and stiffness were evaluated using a Cybex dynamometer and shear-wave ultrasound elastography, respectively. Knee OA was defined based on clinical criteria 24 months later. Logistic regression with generalized estimating equations was used to examine the association between quadriceps properties and DJS and incident knee OA. Mediation analysis was performed to explore the mediation role of DJS in associations between quadriceps properties and the incidence of knee OA. RESULTS: A total of 125 participants (65.6 ± 4.0 years, 58.4% females) completed the 24-month follow-up, with 36 out of 250 knees identified as clinical knee OA. Higher DJS (OR = 1.86, 95%CI: 1.33-2.62), lower quadriceps strength (1.85, 1.05-3.23), and greater quadriceps stiffness (1.56, 1.10-2.21) were significantly associated with a higher risk of clinical knee OA. Mediation analysis showed that the DJS was not a significant mediator for the associations between quadriceps properties and knee OA. CONCLUSIONS: Higher sagittal knee dynamic joint stiffness, lower quadriceps strength, and greater quadriceps stiffness are potential risk factors for developing clinical knee OA in asymptomatic elders. Associations between quadriceps properties and knee OA may not be mediated by dynamic joint stiffness. Interventions for reducing increased passive properties of the quadriceps and knee joint stiffness may be beneficial for maintaining healthy knees in the aging population.

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.

Safety and efficacy of the modified Judet quadricepsplasty in patients with post-traumatic knee stiffness.

BACKGROUND: Knee stiffness is a challenging complication following complex fractures around the knee. Several treatment strategies have been described in the last decades, but clinical results and complication rates still remain as potential drawbacks. The aim of this study was to access the clinical outcomes and complications of the modified Judet quadricepsplasty following knee stiffness secondary to complex fractures around the knee. METHODS: A total of 11 patients presenting post-traumatic knee stiffness underwent modified Judet quadricepsplasty from 2014 to 2017. All procedures were performed by the same surgical team, and all patients followed the same postoperative pain control and rehabilitation protocols. No patients underwent medial approach for medial release. When necessary, medial release was performed through the lateral approach. Patients were evaluated using the Judet criteria for final range of motion after 1-year minimum follow-up. RESULTS: According to the Judet criteria, 4 patients (36.4%) presented excellent, 6 (54.5%) good, and 1 (9.1%) poor clinical outcomes. Blood transfusion was required in 5 patients (45.4%). No patients presented infection or wound dehiscence. CONCLUSIONS: Although quadricepsplasty is considered a high morbidity surgical procedure, our favorable functional outcomes with very low complication rates using this modified Judet quadricepsplasty confirmed safety and efficacy of this helpful surgical procedure for the challenge of post-traumatic knee stiffness. LEVEL OF EVIDENCE: Level 4 retrospective case series.

Treatment of posttraumatic patella osteomyelitis with MRSA infection and knee stiffness: a case report.

BACKGROUND: Posttraumatic patella osteomyelitis is rare, and the treatment of osteomyelitis remains to be challenging. Control of the infection commonly costs a long time, and it is easily to cause knee stiffness. In addition, there is no unified protocol for the treatment of knee stiffness. CASE PRESENTATION: We reported a case of posttraumatic patella osteomyelitis that successive infected with methicillin-resistant staphylococcus aureus (MRSA) after multiple surgeries. We successfully treated osteomyelitis by one-staged surgery, but the patient present knee stiffness after treatment. Thus Ilizarov external fixation system was further used to gradually adjust the mobility by exerting mechanical stress to the joint. After adjusting the frame under a scheduled plan, the patient successfully restored satisfactory knee function. CONCLUSIONS: Adequate debridement is the key to control infections of posttraumatic osteomyelitis. Control the infection of posttraumatic patella osteomyelitis by one-staged surgery is achievable and could shorten the knee immobilization period. When knee stiffness occurs, scheduled range of motion (ROM) adjustment using Ilizarov frame with hinges might be a safe and useful method to restore function.

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.

Prevalence and healthcare usage of knee pain in South Australia: a population-based study.

BACKGROUND: It is known that South Australia (SA) has the highest rate of knee arthroscopy use of any state in Australia; however, Level 1 evidence demonstrates that knee arthroscopy in patients with uncomplicated knee osteoarthritis confers no benefit. In SA, which patients are presenting with knee pain and what treatments are they receiving? AIMS: To determine the prevalence, persistence and treatment modalities of knee pain in SA. METHODS: This study analysed data from the North-West Adelaide Health Study (1999-2015), a longitudinal, population-based cohort study of people aged 18 years and over (n = 4060), initially randomly selected from the north-west region of Adelaide, SA. It incorporated clinic assessments, self-completed questionnaires and telephone interviews to collect demographic, anthropometric and biochemical data over four main stages (1, 2, 3 and North-West 15 (NW15)). Data were linked to Medical Benefits Scheme data. RESULTS: In stages 3 and NW15 of the North-West Adelaide Health Study, 30-35% of participants reported knee pain (n = 803, 452). Demographic variables associated with knee pain included older age and lower educational level, while risk factors included obesity and high waist circumference. In the 12 months preceding NW15, 33% of participants with knee pain/stiffness consulted a general practitioner for their knee pain, 10.2% an orthopaedic surgeon, and 12.6% a physiotherapist. Between 2011 and 2015, 3.0% the cohort underwent a knee arthroscopy, and 3.1% underwent knee magnetic resonance imaging. CONCLUSIONS: Knee pain affects large proportions of the SA population. Knee pain was persistent with underuse of non-pharmacological treatments and high use of specialist referral. These data support the need for a national strategy to manage osteoarthritis effectively.

Evaluation of Thompson's quadricepsplasty results in patients with knee stiffness resulted from femoral fracture.

BACKGROUND: Posttraumatic and/or postsurgical knee stiffness is one of the orthopedic complications which is difficult to be treated and can affect individual's life negatively. The aim of this study is to investigate the results of quadricepsplasty in patients with knee stiffness resulted from femoral fracture. MATERIALS AND METHODS: This is a cross-sectional study on all patients with femoral fracture which has caused knee flexion limitation referred to Kashani and Al-Zahra Hospitals in Isfahan from January 2010 to March 2013. The type and site of fracture, joint extension, and fracture fixation technique were recorded. Moreover, the range of motion (ROM) before surgery, under general anesthesia, and 3- and 6-month postoperation were measured. RESULTS: Among the patients, 13 had a simple fracture (48%) and 14 had a segmental fracture (51.9%). Considering the fracture site, 11, 10, and 6 patients had femoral (40.74%), supracondylar (37.3%), and femoral supracondylar (22.2%) fractures, respectively. The fracture fixation was performed by the plate, external, and Wagner fixation techniques for 24 (88.9%), 2 (7.4%), and 1 (3.7%) patients, respectively. The mean ROM before operation, under general anesthesia, and 3- and 6-month postoperation were determined to be 33.15° ± 24.73°, 122.60° ± 10.22°, 99.63° ± 16.52°, and 100.74° ± 15.67°, respectively. The mean ROM value at various stages was not similar (P < 0.001). The mean changes in the ROM were 79.2° ± 24.6° and 62.1° ± 19.7° in the cases with simple and segmental fractures, respectively. The mean changes in the knee ROM were significantly higher in simple fractures in comparison with the segmental femoral fracture (P = 0.03). CONCLUSION: We found Thompson's quadricepsplasty may successfully increase the range of knee flexion in knee fracture and also regardless of quadriceps time.

Women and Minorities Are at Risk of Developing Unexpected Reduction of Preoperative Flexion After Total Knee Arthroplasty.

BACKGROUND: Reduced flexion after total knee arthroplasty (TKA) compared to the preoperative values can affect patient's activities of daily living and lead to patient dissatisfaction. The aim of this study was to determine preoperative risk factors for developing a decrease in knee flexion after a primary TKA. METHODS: We identified 37 knees diagnosed with osteoarthritis with a preoperative knee flexion ≥120° but a 12-month postoperative range of motion (ROM) ≤110°. A random sample of 111 patients (1:3) from the same database, whose knees had a preoperative and 12-month postoperative ROM ≥120°, based on a diagnosis of primary osteoarthritis and no previous open knee surgery, were selected as the controls. RESULTS: We found female gender, black ethnicity, and the low preoperative knee-specific Knee Society Score to be significant risk factors for developing a reduction of knee flexion after TKA with odds ratios of 3.48, 5.11, and 0.95, respectively. CONCLUSION: In the absence of the well-recognized preoperative risk factors for a limited postoperative ROM, female patients, minorities, and those with lower knee-specific Knee Society Scores are at an increased risk of developing a decrease in flexion after an elective primary TKA.

Inflammatory cytokine expression in the quadriceps of rats with posttraumatic knee stiffness: A preliminary study.

The primary purpose of this study was to investigate cytokine expression in the quadriceps of rats with posttraumatic knee stiffness (PTKS) and to determine the effect of exercise training on these cytokines at different follow-up time points. The PTKS rats were randomly assigned into two even groups. The treatment group received exercise training, while the control group received no treatment. Quadriceps specimens were harvested randomly from each group at 8, 12, 16, and 20 weeks. RT-qPCR and immunohistochemical analyses were used to assess the protein and mRNA expression levels of the cytokines IL-1, IL-2, TNF-α, COX-1, and COX-2. TNF-α immunostaining did not differ between the treated and control group tissues, whereas weak immunostaining was observed for all other cytokines in the specimens from the treatment group compared with those from the control group at approximately 12 and 20 weeks. The cytokine levels decreased at approximately 8 weeks in the treatment group, whereas these levels remained elevated or plateaued in the control group. These differences were statistically significant (p<0.05). This study demonstrated that the expression of cytokines IL-1, IL-2, COX-1, and COX-2 increased in the quadriceps of rats with PTKS and that exercise training affected the observed profile trends of these cytokines.

Proximalize osteotomy of tibial tuberosity (POTT) as a treatment for stiffness secondary to patella baja in total knee arthroplasty (TKA).

INTRODUCTION: Stiffness after a total knee arthroplasty (TKA) is one of the most common post-operative complications. The purpose of this study is the evaluation of the effectiveness of TT proximalization osteotomy of improving a lack of flexion and secondary pain in patella baja (infera) post-TKA. MATERIALS AND METHODS: Between April 2007 and July 2012, TT proximalization osteotomy was performed on 21 patients. The average preoperative flexion was 70° (in a range of 60-80). Clinical pre- and post-operative evaluations were performed with Knee Society Score, Western Ontario and McMaster Universities Arthritis Index scales and a satisfaction survey. Modified Blackburn-Peel index and Portner angle were used to evaluate patellar height. RESULTS: After an average follow-up of 35 months (range 18-48), an average flexion of 100° (range 90-100) and an overall satisfaction were obtained. Clinical scores improved significantly. The Blackburn-Peel index and Portner angle improved significantly from 0.3 (range 0.1-0.5) to 0.4 (0.3-0.5) and from 9 (3-15) to 12 (9-18), respectively. Three patients showed no signs of osteotomy consolidation. However, this was not linked to a lack of extension or an increase in local pain. CONCLUSION: TT proximalization osteotomy provides satisfactory results in improving a lack of flexion and pain in patella baja post-TKR.

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).

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

The purpose of this study was to determine the clinical outcomes of manipulation under anesthesia (MUA) in a cohort who had developed knee stiffness following total knee arthroplasty (TKA). One-hundred and forty-five TKAs in 134 patients who had undergone MUA were compared to the remaining 1973 TKAs in 1671 patients who did not develop this condition. At a mean follow-up of 51 months (range, 24 to 85 months), the mean gains in flexion in the MUA cohort were 33° (range, 5° to 65°). The final range-of-motion in the MUA cohort was lower than the comparison cohort (114° versus 125°) however, this would meet the required flexion for activities of daily living. There were no differences in the Knee Society objective and functional scores between the two cohorts. It is encouraging that MUA cohort outcomes were comparable to outcomes of patients who did not develop knee stiffness.

Clinical Outcomes of Arthroscopic Adhesiolysis: A Case Series of 40 Patients With Postoperative Knee Stiffness.

Introduction Restricted range of motion over the knee joint is a known complication following the surgical procedure. Aggressive rehabilitation protocols can initially manage knee stiffness due to arthrofibrosis. If conservative management fails, surgical (open or arthroscopic) release is the preferred modality of management. We present a series of 40 patients with postoperative knee stiffness who were treated with arthroscopic adhesiolysis. Material and methods This is a retrospective study conducted at Phoenix Orthopedic Superspeciality Hospital, Nagpur, India, from 2017 to 2021. Our study included 40 patients with postoperative knee joint stiffness, of whom 27 were males and 13 were females. The study considered the duration of stiffness, which ranged from six months to five years. All patients underwent arthroscopic knee release. A rigorously supervised physical therapy program followed this procedure. Patients were examined at three months, six months, and one year to assess improvement in knee range of movement. Results Out of 40 patients, six were classified as Shelbourne type 4, and the remaining were Shelbourne type 3. Twenty-three of 40 patients developed arthrofibrosis following intra-articular or peri-articular fracture fixation surgery; 11 patients were operated on arthroscopically for anterior cruciate ligament (ACL) or posterior cruciate ligament (PCL) reconstruction. Three patients developed stiffness following total knee replacement, one following patellectomy, and three following infection after fracture fixation. The mean pre-op knee range of motion (ROM) was 48.875 degrees. Following arthroscopic release, the mean improvement in ROM was 60 degrees intra-operatively. The average postoperative range was 108.25 degrees. Conclusion Arthroscopic adhesiolysis and quadriceps release are reliable methods for dealing with postoperative knee stiffness. It prevents wound complications and increases the chances of surgical site infection due to smaller incisions. Postoperatively, we achieved an average increase of 60 degrees in ROM over the knee joint.

Increased symptoms of stiffness after opening-wedge high tibial osteotomy are associated with worse postoperative knee function outcomes and lower patient satisfaction rate.

BACKGROUND: Symptoms of knee stiffness after open wedge high tibial osteotomy (OW-HTO) can significantly affect surgical effectiveness, but no studies have reported risk factors for knee stiffness after OW-HTO. METHODS: Patients treated with OW-HTO for the first time between 2018 and 2021 were included. Data were collected on patient demographics, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Short Form (SF) 12 scores, hip-knee-ankle angle (HKA) and patient satisfaction before and after surgery. Patients with worse WOMAC stiffness scores at 1 year were defined as the 'increased stiffness' group and the other cohort as the 'non-stiffness' group. The primary outcome of the study was to compare postoperative knee function scores (WOMAC and SF-12), HKA and patient satisfaction rate between the two groups. The secondary outcome was the use of logistic regression to analyze independent predictors of increased postoperative stiffness symptoms. RESULTS: At 1 year postoperatively, 95 (11.3%) patients had a significant increase in stiffness. Patients had significantly (p < .001) less improvement in pain, function, and total WOMAC scores, and SF-12 score than those in the non-stiffness group (n = 745). However, the differences in WOMAC and SF-12 scores in increased stiffness group at 1 year post-operatively were statistically significant (p < .001) compared to the non-stiffness group. There was no statistically significant difference in HKA in the increased stiffness group (172.9° ± 2.3°) compared to non-stiffness group (173.4° ± 2.6°) at 1 year postoperatively (p = .068). Patient satisfaction was significantly lower in the increased stiffness group (p < .001). Logistic regression analysis showed that diabetes (odds ratio (OR) 1.809, p = .034) and preoperative WOMAC stiffness score of 44 or less (OR 4.255 p < .001) were predictors of increased stiffness. CONCLUSIONS: Patients with increased stiffness after OW-HTO had worse functional outcomes and lower patient satisfaction rates and patients at risk of being in this group should be informed pre-operatively.

Surgically treated acute knee dislocations with knee stiffness perform equally as well as non-stiff knees when treated with arthroscopic arthrolysis.

PURPOSE: Postoperative knee stiffness is a common issue in multiligament knee injuries (MLKIs). This study aims to compare outcomes between MLKI patients who underwent postoperative arthroscopic lysis of arthrofibrosis (LOA) for limited range of motion (ROM) and those who did not. METHODS: Thirty-one patients (10 IIIM, nine IIIL and 12 IV) were included in this retrospective clinical study with acute type III or IV knee dislocations, while two patients were lost to follow up. Thirteen patients underwent LOA at a mean of 18.7 ± 8.4 weeks (Group A), while 18 did not require this intervention (Group B). Patient-reported outcome measures (IKDC, Lysholm, VAS) and ROM were evaluated. RESULTS: The average follow up period was 31.0 ± 10.2 months. The mean time to LOA was 19.4 ± 7.6 weeks and a significant increase in ROM was observed after LOA (flexion: before LOA: 83.8° ± 19.2, after LOA: 119.6° ± 9.9; P < 0.0001). There were no significant differences between groups regarding clinical scores (Lysholm: Group A 85.0 ± 13.4, Group B 84.6 ± 14.5; IKDC: Group A 74.3 ± 10.8, Group B 76.7 ± 14.7) and ROM (flexion: Group A 118.6° ± 9.8, Group B 124.3° ± 12.8). There were no complications regarding LOA. CONCLUSIONS: Patients, whether undergoing LOA or not, performed equally well in terms of ROM and clinical scores at final follow up, while timing of LOA appears less critical. LOA is a simple, durable and safe method of treating ROM deficits in patients treated for acute knee dislocation, with very good results.

Arthroscopic Arthrolysis of Knee: Timing, Technique and Results.

Aim: To evaluate the functional outcomes of patients undergoing arthroscopic arthrolysis of the knee and find the ideal timing for arthrolysis to achieve maximum range of motion (ROM) of the knee. Methods: All patients who underwent arthroscopic arthrolysis for post-operative joint stiffness following surgery for injuries around knee joint at a tertiary care centre from 2009 to 2023 were included in this study. The patients' details such as primary injury, time interval between the index surgery and arthrolysis, improvement in knee range of ROM and Lysholm score from prior to arthrolysis to last follow-up post arthrolysis were retrieved from hospital database and analysed. Results: Total of 42 patients who underwent arthroscopic arthrolysis of knee from 2009 to 2023 were included in this study. Follow-up range was 6 months to 6 years. ROM after arthrolysis significantly improved in the early and delayed arthrolysis groups as compared to late arthrolysis groups (mean 126.25 and 115.62 vs 106.3, p < 0.05). Patients treated with early arthroscopic arthrolysis (within 3 months) showed significant increase in post operative Lysholm score compared to other groups (p < 0.05). ROM of 120° and beyond was achieved in 75% of cases in early arthrolysis group compared to 62.8% and 39% in delayed and late arthrolysis group (p < 0.05). Conclusions: Arthroscopic arthrolysis done within 6 months (with maximum effect when done within 3 months) after the primary surgery leads to significant improvement in ROM and functional scores as compared to those with late arthrolysis group.

Pre-operative patient education is associated with decreased risk of arthrofibrosis after total knee arthroplasty: a case control study.

The purpose was to investigate risk factors for postoperative stiffness and long-term outcome following manipulation under anaesthesia (MUA). In one of the five Danish regions, all patients in a 4-year period who received MUA following total knee arthroplasty (N=36) were included in two case-control studies. Data on potential risk factors were extracted from the Danish Knee arthroplasty Register and from a postal questionnaire including long-term outcome measures regarding pain, function and quality of life (Oxford Knee Score and EQ-5D). Previous knee surgery and a high preoperative Knee Society Function Score were significant risk factors, whereas attending a preoperative information meeting was associated with a significantly decreased risk of postoperative stiffness requiring MUA (P<0.001). The long-term results following MUA (1-5 years) were equivalent to patients without postoperative stiffness.

Risk factors for failure of manipulation under anesthesia in posttraumatic knee stiffness.

OBJECTIVES: To determine the proportion of patients who fail manipulation under anesthesia (MUA) as a treatment for posttraumatic knee stiffness and determine the risk factors for MUA failure. METHODS: A retrospective cohort study was performed at a level I trauma center. We identified 213 knees in 199 patients with arthrofibrosis treated by MUA within 1 year of injury from 2007 to 2020. The primary outcome was MUA failure as defined by need for repeat MUA or surgical release after MUA. Multivariable logistic regression was used to determine the association between MUA failure and potential risk factors. RESULTS: Overall, 111 knees (52%) failed treatment with MUA. An association was demonstrated between MUA failure and delay in treatment >90 days after injury (OR 3.6, p < 0.01), neurologic injury (OR 2.2, p = 0.02), and pre-procedure knee flexion <45° (OR 1.9, p < 0.01). The rate of failure for knees with no risk factors was 0% (0 of 14), 37% for knees with one risk factor (27 of 73), and 67% (84 of 126) for knees with two or more risk factors. CONCLUSION: For patients whose MUA is delayed beyond 90 days postinjury, pre-manipulation knee flexion is <45°, or those with associated neurologic injury; odds of MUA failing to correct posttraumatic arthrofibrosis are significantly increased. The likelihood of obtaining adequate range of motion (ROM) with MUA alone is lower than reported in other populations, with a higher likelihood of being treated with surgical release or additional MUA to attempt to obtain adequate ROM.

Understanding rates, risk factors, and complications associated with manipulation under anesthesia after total knee arthroplasty (TKA): An analysis of 100,613 TKAs.

BACKGROUND: Considering the growing adoption of technology-assisted total knee arthroplasties (TKA), previous database studies evaluating post-operative stiffness may be outdated. The present study aimed to: (1) evaluate the incidence of manipulation under anesthesia (MUA) after primary TKA; (2) determine independent risk factors for MUA; and (3) assess complications after MUA. METHODS: Primary TKAs, with at least 6-month follow-up, were identified from the Florida State Inpatient Database (January 2016-June 2018) and linked to outpatient records from the Florida State Ambulatory Surgery and Services Database. Multivariable regression analyses were performed to compare patient factors and complications (e.g., mechanical, non-mechanical, infectious) associated with MUA, while adjusting for baseline demographics, comorbidities, use of robotic- and computer-technologies, time to MUA (0-3, 3-12, or >12 months), and need for repeat MUA (one-time vs >1). RESULTS: The MUA rate was 2.8% (2821 of 100,613). Being younger, a woman, Black or Hispanic; having private or self-pay insurance; and conventional TKA were associated with significantly higher odds of undergoing MUA. Higher rates of mechanical complications and acute posthemorrhagic anemia were observed in the MUA cohort. Time to MUA, repeat MUA, and baseline demographics were not associated with complication rates among the MUA cohort. CONCLUSION: Overall, 1 in 36 patients underwent MUA after primary TKA. Several non-modifiable patient characteristics, such as Black or Hispanic race, female sex, and younger age were associated with an increased risk of MUA. However, technology-assisted TKA might help to decrease the risk of MUA.

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.