Predictors of outcome after manipulation under anaesthesia in patients with a stiff total knee arthroplasty

Risk factors for failure of manipulation under anesthesia after total knee arthroplasty

BACKGROUND

Manipulation under anesthesia (MUA) is a well-established treatment for stiffness after total knee arthroplasty (TKA). Risk factors for failure of MUA remain largely unknown. The primary aim of this study was to identify risk factors for failure of MUA after TKA.

METHODS

We performed a retrospective cohort study including 470 patients who underwent MUA after primary TKA with minimum 2 year follow-up. Patients were grouped into success (n = 412) or failure (n = 58) cohorts; failure was defined as flexion < 90° at most recent follow-up or revision for stiffness. The increase in flexion post-MUA for the cohort was calculated. Several clinical, patient, and surgical factors were analyzed using univariate, followed by multivariable logistic regression models to identify independent risk factors associated with failure.

RESULTS

The mean increase in flexion was 42° (range 0-115). BMI 30-35 (p = 0.01, odds ratio (OR) 2.42; 95% CI 1.25-4.68) and poorer pre-MUA flexion (p < 0.01, OR 1.43; 95% CI 1.23-1.67) were risk factors for failure. When considering revision for stiffness only, BMI 30-35 (p = 0.01, OR 3.27; 95% CI 1.41-7.61), lower pre-MUA flexion (p < 0.01, OR 1.43; 95% CI 1.18-1.75), and history of prior knee surgery (p = 0.04, OR 2.31; 95% CI 1.06-5.04) were predictors of failure. Time to MUA (p = 0.48), thromboprophylaxis (p = 0.44), pre-operative opioid use (p = 0.34), depression/anxiety (p = 1.0), and several other factors analyzed were not associated with failure.

CONCLUSION

In this large cohort, elevated BMI and lower pre-MUA flexion were risk factors for failure of MUA. History of prior knee surgery was an additional predictor of requiring revision for stiffness.

Early manipulation under anaesthesia for stiffness following total knee arthroplasty is associated with a greater gain in knee flexion

PURPOSE

This study aimed to identify the risk factors for manipulation under anaesthesia (MUA) following total knee arthroplasty (TKA) and whether performing an 'early' MUA within 3 months leads to a greater improvement in range of motion.

METHODS

Primary TKAs performed between 2013 and 2018 at three tertiary New Zealand hospitals were reviewed with a minimum follow-up of 1 year. Clinical details of patients who underwent MUA were reviewed to identify the knee flexion angle prior to and following MUA. Multivariate analysis identified the risk factors for undergoing MUA and compared flexion angles between 'early' (< 3 months) and 'late' MUA (> 3 months).

RESULTS

A total of 7386 primary TKAs were analysed in which 131 underwent an MUA (1.8%). Patients aged < 65 years were two times more likely to undergo MUA compared to patients aged ≥ 65 years (2.5 versus 1.3%, p < 0.001; adjusted HR = 2.1, p < 0.001). There was no difference in the final flexion angle post-MUA between early and late MUA (104.7° versus 104.1°, p = 0.819). However, patients who underwent early MUA had poorer pre-MUA flexion (72.3° versus 79.6°, p = 0.012), and subsequently had a greater overall gain in flexion compared to those who underwent late MUA (mean gain 33.1° versus 24.3°, p < 0.001).

CONCLUSION

Younger age was the only patient risk factor for MUA. Patients who underwent early MUA had similar post-MUA flexion, but had poorer pre-MUA flexion compared to those who underwent late MUA. Subsequently, a greater overall gain in flexion was achieved in those who underwent early MUA.

LEVEL OF EVIDENCE

III.

The Effect of Early versus Late Manipulation Under Anesthesia on Opioid Use, Surgical Complications, and Revision Following Total Knee Arthroplasty

Previous studies of early versus late manipulation under anesthesia (MUA) do not report on postoperative opioid utilization or revisions and focused on small single-institution retrospective cohorts. The PearlDiver Research Program (www.pearldiverinc.com), which uses an all-inclusive insurance database, was used to identify patients undergoing primary total knee arthroplasty (TKA) who received (1) late MUA (>12 weeks), (2) early MUA (≤12 weeks), or (3) TKA only. To develop the control group cohort of TKA-only patients, 3:1 matching was conducted using 11 risk factor variables deemed significant by chi-squared analysis. Complications and opioid utilization were compared through multivariate regression analysis, controlling for age, gender, and Charlson Comorbidity Index. The risk of TKA revision was assessed through Cox-proportional hazards modeling and Kaplan-Meier survival analysis with log-rank test. Between 2011 and 2017, 2,062 TKA patients with early MUA, 1,112 TKA patients with late MUA, and a control cohort of 8,327 TKA-only patients were identified in the database. The percent of patients registering opioid use decreased from 54.6% 1 month pre-MUA to 4.6% (p < 0.0001) 1 month post-MUA following early MUA, whereas only from 32.6 to 10.4% (p < 0.0001) following late MUA. Late MUA was associated with higher risk of repeat MUA at 6 months (adjusted odds ratio [aOR] = 2.74, p < 0.0001), 1 year (aOR = 2.66, p < 0.0001), and 2 years (aOR = 2.63, p < 0.0001) following index MUA. Hazards modeling and survival analysis showed increased risk of TKA revision following late MUA (adjusted hazard ratio [aHR] = 3.50, 95% confidence interval [CI]: 2.77-4.43, p < 0.0001) compared to early MUA (aHR = 2.15, 95% CI: 1.72-2.70, p < 0.0001), with significant differences in survival to revision curves (p < 0.0001). When compared to early MUA at 1 year, late MUA was associated with a significantly increased risk of prosthesis explantation (aOR = 2.89, p = 0.0026 vs. aOR = 0.93, p = 0.8563). MUA within 12 weeks after index TKA had improved pain resolution and significant curtailing of opioid use. Furthermore, late MUA was associated with prolonged opioid use, increased risks of revision, as well as prosthesis explantation, supporting screening and early intervention in cases of slow progression and stiffness. The level of evidence of this study is III.

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

BACKGROUND AND PURPOSE

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

PATIENTS AND METHODS

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

RESULTS

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

INTERPRETATION

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

Manipulation under Anesthesia after Knee Arthroplasty Is Associated with Worse Long-Term Clinical Outcomes and Survivorship

The literature is mixed on the long-term fate of knees that undergo manipulation under anesthesia (MUA). The purpose of this study is to evaluate the long-term outcomes and survivorship of patients who required a MUA after primary total knee arthroplasty (TKA) compared with a cohort of patients who did not undergo a MUA. Between 2003 and 2007, 2,193 patients (2,783 knees) underwent primary TKA with 2-year minimum follow-up; 182 knees (6.5%) had a MUA. Patients who had a manipulation were younger (p < 0.001) and had worse preoperative range of motion (ROM) (p < 0.001). Postoperative ROM, Knee Society clinical (KSC), functional, and pain (KSP) scores, revisions, and survivorship were compared between MUA and no MUA. Mean follow-up was 9.7 years. MUA patients had lower postoperative ROM (p < 0.001), change in ROM (p < 0.001), KSC (p < 0.001), KSP (p < 0.001), and change in KSP scores (0.013). Revisions occurred in 18 knees (9.9%) in the MUA group compared with 77 knees (3%) without a MUA (p < 0.001). Most common reason for revision after MUA was continued stiffness (50%). Relative risk for revision after one MUA was 2.01 (95% confidence interval [CI], 1.1-3.8, p < 0.001) and after three or more MUAs were 27.02 (95% CI, 16.5-44.1, p < 0.001). Ten-year survival after MUA was 89.4% (95% CI, 87.1-91.7%) compared with 97.2% (95% CI, 96.9-97.5%) without a MUA (p < 0.001). Patients who undergo a MUA after primary TKA may have a knee at risk with higher revision rates, worse long-term clinical scores, ROM and survivorship.

Patients undergoing manipulation after total knee arthroplasty are at higher risk of revision within 2 years

BACKGROUND

Total knee arthroplasty (TKA) is a very common orthopedic procedure and stiffness is a common complication following TKA. There is extensive data regarding timing and success of Manipulation under anesthesia (MUA) for stiffness following TKA. However, Studies reporting outcome following MUA have often focused on the improvement in ROM and improvement in functional score with very few studies reporting on the revision risk.

METHODS AND MATERIALS

In this study we retrospectively reviewed PearlDiver insurance database and analyzed the characteristics of the patient undergoing MUA after TKA. We also analyzed the risk of revision at 2 years in a cohort of MUA patients who were matched to patients without MUA.

RESULT

Our study identified 9156 patients who underwent MUA within one year following TKA. MUA was slightly more common in females and risk of manipulation decreases with increasing age. Comparative analysis showed that at two years, patients in the matched MUA cohort (538 patients, 5.99%) were 2.9 times more likely to undergo revision TKA compared to the matched non MUA group (194, 2.16%)OR 2.88 (95% CI-2.44 to 3.41), P < 0.05 CONCLUSION: Retrospective database review showed that the risk of revision is higher in patients undergoing MUA after TKA and hence patient should be counselled about the possibility of revision in the future.

Outcome of Revision Surgery for the Idiopathic Stiff Total Knee Arthroplasty

BACKGROUND

Idiopathic stiff total knee arthroplasty (TKA) represents one of the most challenging subsets of the stiff TKA, as the etiology is unknown and there is no consensus on the most appropriate surgical treatment modality. Therefore, the aim of this study is to report on postoperative outcomes of revision surgery for idiopathic stiff TKA.

METHODS

We retrospectively reviewed 189 consecutive patients (202 knees) who underwent revision TKA for stiffness: (1) 101 knees in the idiopathic stiffness cohort and (2) 88 in the non-idiopathic stiffness cohort. In the idiopathic stiffness cohort, 42 knees underwent isolated tibial insert exchange and 59 knees underwent component revision. Perioperative knee range of movement and complications were analyzed.

RESULTS

The overall revision surgery outcomes of the idiopathic stiffness cohort were worse than those of the non-idiopathic stiffness cohort with regard to maximum flexion (91.7° vs 100.1°, P = .02) and flexion range of motion (ROM) (87.6° vs 97.1°, P = .01). In the idiopathic stiffness cohort, isolated tibial insert exchange demonstrated greater maximum flexion (96.8° vs 88.4°, P = .06) and flexion ROM (93.2° vs 83.9°, P = .07). In terms of re-revision rates, the isolated tibial insert exchange idiopathic stiffness cohort demonstrated lower re-revision rates compared to the component revision idiopathic stiffness cohort (16.7% vs 31.0%, P = .01).

CONCLUSION

This study demonstrates that the overall revision surgery outcome of idiopathic stiff TKA is worse than non-idiopathic TKA stiffness. In idiopathic stiffness cohorts, isolated tibial insert exchange was associated with lower re-revision rates than component revision, with similar efficacy in improving ROM, suggesting that isolated tibial insert exchange may be a preferred surgical treatment option in TKA patients with idiopathic stiffness.

Quantification of intra-articular fibrosis in patients with stiff knee arthroplasties using metal-reduction MRI

AIMS

Stiffness is a common complication after total knee arthroplasty (TKA). Pathogenesis is not understood, treatment options are limited, and diagnosis is challenging. The aim of this study was to investigate if MRI can be used to visualize intra-articular scarring in patients with stiff, painful knee arthroplasties.

METHODS

Well-functioning primary TKAs (n = 11), failed non-fibrotic TKAs (n = 5), and patients with a clinical diagnosis of fibrosis1 (n = 8) underwent an MRI scan with advanced metal suppression (Slice Encoding for Metal Artefact Correction, SEMAC) with gadolinium contrast. Fibrotic tissue (low intensity on T1 and T2, low-moderate post-contrast enhancement) was quantified (presence and tissue thickness) in six compartments: supra/infrapatella, medial/lateral gutters, and posterior medial/lateral.

RESULTS

Fibrotic tissue was identified in all patients studied. However, tissue was significantly thicker in fibrotic patients (4.4 mm ± 0.2 mm) versus non-fibrotic (2.5 mm ± 0.4 mm) and normal TKAs (1.9 mm ± 0.2 mm, p = < 0.05). Significant (> 4 mm thick) tissue was seen in 26/48 (54%) of compartments examined in the fibrotic group, compared with 17/30 (57%) non-fibrotic, and 10/66 (15%) normal TKAs. Although revision surgery did improve range of movement (ROM) in all fibrotic patients, clinically significant restriction remained post-surgery.

CONCLUSION

Stiff TKAs contain intra-articular fibrotic tissue that is identifiable by MRI. Studies should evaluate whether MRI is useful for surgical planning of debridement, and as a non-invasive measurement tool following interventions for stiffness caused by fibrosis. Revision for stiffness can improve ROM, but outcomes are sub-optimal and new treatments are required. Cite this article: Bone Joint J 2020;102-B(10):1331-1340.

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

Aims

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

Methods

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

Results

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

Conclusion

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

Recovery of knee range of motion after total knee arthroplasty in the first postoperative weeks: poor recovery can be detected early

PURPOSE

The aim of this study was to analyze in detail how knee flexion and extension progress in the first 8 weeks after primary total knee arthroplasty (TKA). The secondary goal was to compare knee range of motion (ROM) recovery patterns between patients with normal and delayed ROM recovery 8 weeks after TKA.

METHODS

This prospective clinical trial included all patients who underwent a primary unilateral TKA between February and December 2016 with weekly ROM data documented by the treating outpatient physical therapists (n = 137). Goniometry was used to measure knee ROM preoperatively, postoperatively on day 1 and weekly until follow-up at the orthopedic clinic 8 weeks after surgery. ROM recovery patterns were compared between patients with sufficient (≥ 90°) or insufficient (< 90°) knee flexion 8 weeks after TKA.

RESULTS

Knee flexion recovered from a median of 80° in the first postoperative week to 110° 8 weeks after surgery and knee extension from a mean of - 10.7° to - 3.2°. Recovery was nonlinear, with greatest improvements in the first 4 weeks for knee flexion. In contrast to patients with sufficient knee flexion 8 weeks postoperatively, the insufficient group (n = 8, 5.8%) had poor knee flexion on the first postoperative day and from week 4 to week 8 almost no improvement or even worsening of knee flexion.

CONCLUSIONS

Both knee flexion and extension recover in a nonlinear manner after TKA surgery. Poor postoperative knee function can be detected early, using ROM data from the first postoperative day up to the fourth week.

Same-Day Surgery Does Not Increase the Manipulation Under Anesthesia and Reoperation Rates for Stiffness Following Bilateral Total Knee Arthroplasty

BACKGROUND

There is a paucity of data on the incidence of stiffness and need for subsequent manipulation under anesthesia (MUA) and reoperation following same-day bilateral total knee arthroplasty (BTKA). We compared the rates of at least 1 MUA, bilateral knee involvement, single and multiple MUA rates, and stiffness-related reoperation rates between patients undergoing same-day, same-admission staged, and staged within 1 year BTKA in a tertiary institution.

METHODS

We analyzed institutional data for 3175 same-day (group A), 153 same-admission staged (group B), and 1226 staged within 1 year BTKA patients (group C) from 1998 to 2009. Several variables, including patient demographics, comorbidity profile, Charlson-Deyo index, and range of motion at different time points, were tabulated. Follow-up was minimum 1 year after first MUA. Univariate analyses were performed using the Wilcoxon rank-sum or Kruskal-Wallis test, and Fisher exact or the chi-square test for continuous and categorical variables, respectively. The Cochran-Armitage trend test was used to check the bilateral knee involvement rate across groups.

RESULTS

Overall, 2.2% (98/4554) of BTKA patients required MUA. The rate of at least 1 MUA was similar across groups but the percentage of bilateral knee involvement was higher in group A. The single MUA rate was comparable among groups. Both no revision and revision reoperation rates were similar among the manipulated groups.

CONCLUSION

Same-day BTKA was not associated with increased incidence of single or multiple MUA and stiffness-related reoperation rates. These findings may facilitate preoperative counseling in patients with symptomatic bilateral knee disease, eligible for same-day BTKA.

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

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

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

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

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

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

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

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

Acquired Idiopathic Stiffness After Total Knee Arthroplasty: A Systematic Review and Meta-Analysis

BACKGROUND

Stiffness is a common reason for suboptimal clinical outcomes after primary total knee arthroplasty (pTKA). There is a lack of consensus regarding its definition, which is often conflated with its histopathologic subcategory-i.e., arthrofibrosis. There is value in refining the definition of acquired idiopathic stiffness in an effort to select for patients with arthrofibrosis. We conducted a systematic review and meta-analysis to establish a consensus definition of acquired idiopathic stiffness, determine its prevalence after pTKA, and identify potential risk factors for its development.

METHODS

MEDLINE, Embase, Cochrane Controlled Register of Trials (CENTRAL), and Scopus databases were searched from 2002 to 2017. Studies that included patients with stiffness after pTKA were screened with strict inclusion and exclusion criteria to isolate the subset of patients with acquired idiopathic stiffness unrelated to known extrinsic or surgical causes. Three authors independently assessed study eligibility and risk of bias and collected data. Outcomes of interest were then analyzed according to age, sex, and body mass index (BMI).

RESULTS

In the 35 included studies (48,873 pTKAs), the mean patient age was 66 years. In 63% of the studies, stiffness was defined as a range of motion of <90° or a flexion contracture of >5° at 6 to 12 weeks postoperatively. The prevalence of acquired idiopathic stiffness after pTKA was 4%, and this did not differ according to age (4%, I = 95%, among patients <65 years old and 5%, I = 96%, among those ≥65 years old; p = 0.238). The prevalence of acquired idiopathic stiffness was significantly lower in males (1%, I = 85%) than females (3%, I = 95%) (p < 0.0001) as well as in patients with a BMI of <30 kg/m (2%, I = 94%) compared with those with a BMI of ≥30 kg/m (5%, I = 97%) (p = 0.027).

CONCLUSIONS

Contemporary literature supports the following definition for acquired idiopathic stiffness: a range of motion of <90° persisting for >12 weeks after pTKA in patients in the absence of complicating factors including preexisting stiffness. The mean prevalence of acquired idiopathic stiffness after pTKA was 4%; females and obese patients were at increased risk.

LEVEL OF EVIDENCE

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

[Open arthrolysis for stiff knee after primary total knee arthroplasty]

Objective

To evaluate the effectiveness of open arthrolysis in treatment of the patient with stiff knee in late stage after primary total knee arthroplasty (TKA).

Methods

Between January 2014 and October 2017, 7 female patients (7 knees) with stiff knee in late stage after primary TKA were admitted. The patients were 57-71 years old (mean, 63 years). There were 2 left knees and 5 right knees. All patients underwent TKA because of knee osteoarthritis. The interval between TKA and open arthrolysis was 8-30 months (mean, 13.6 months). There were 4 patients with 10-20° of extension deficit before arthrolysis. The range of motion of knee was (54.3±12.1)°. The clinical score, functional score, and total score of Knee Society Score (KSS) before arthrolysis were 76.3±7.6, 67.9±11.1, and 144.1±16.1, respectively. During the arthrolysis, periarticular soft tissue scar was removed, the range of motion of knee was restored, the gap balance and well patellar tracking were maintained. Intensive rehabilitation after operation was supplemented.

Results

All wounds healed by first intention, without early stage complications. All patients were followed up 12-32 months with an average of 20.1 months. No abnormality of prosthesis was found by post-operative X-ray films. The knee movement improved significantly when compared with that before arthrolysis. The range of motion was less than 90° in 1 patient and 10° of extension deficit remained in 1 patient after operation. The range of motion was (92.9±4.9)° at last follow-up. The clinical score, functional score, and total score of KSS were 81.9±5.1, 74.3±9.8, and 156.1±13.7, respectively at last follow-up. The above indexes were superior to those before operation ( P<0.05).

Conclusion

Open arthrolysis combined with intensive rehabilitation is a significant way to improve knee function for the patient with stiff knee in late stage after primary TKA.

All-arthroscopic release for treating severe knee extension contractures could improve the knee range of motion and the mid-term functional outcomes

PURPOSE

To evaluate the safety, feasibility, and effectiveness of an all-arthroscopic technique for the intra- and extraarticular release of severe knee extension contractures.

METHODS

From 2012 to 2016, 25 patients with severe knee extension contractures (less than 45° range of flexion) were treated with an all-arthroscopic release technique. The patients underwent intra- and extraarticular arthroscopic release and arthroscopic-assisted mini-incision quadriceps plasty. The post-operative rehabilitation was initiated the first day after the procedures. Comprehensive clinical follow-up evaluations including the range-of-motion (ROM) assessment, the Lysholm score, and the International Knee Documentation Committee (IKDC) score were performed on all patients.

RESULTS

The median follow-up time was 28 months (range 12-65 months). The ROM improved from 23.9° ± 7.5° pre-operatively to 105.9° ± 6.5° at the final follow-up (P < 0.001). In addition, the Lysholm score increased from 59.9 ± 5.2 pre-operatively to 89.7 ± 3.3 (P < 0.001). The IKDC score increased from 47.6 ± 3.4 pre-operatively to 91.7 ± 2.4 (P < 0.001). All patients were satisfied with their final ROM and functional outcomes.

CONCLUSION

The all-arthroscopic release technique was a safe, feasible and effective method for treating severe knee extension contractures. The severe knee extension contractures may be successfully addressed by the all-arthroscopic release technique during our clinical practice.

LEVEL OF EVIDENCE

IV.

Hinged versus CCK revision arthroplasty for the stiff total knee

BACKGROUND

Total knee arthroplasty (TKA) remains the gold standard for end-stage knee osteoarthritis. The prevalence of stiffness after this procedure described in literature varies from 1.3% to 5.3%. The causes of arthrofibrosis after total knee arthroplasty are multifactorial. Revision TKA is a successful procedure when performed for loosening, instability, mechanical implant failure, or infection. The results of revision TKA for idiopathic arthrofibrosis and stiffening are however less favorable.

PURPOSE

It has been the authors' impression that the poor results in arthrofibrosis could be in part related to the use of traditional PS or CCK-type revision implants. Our hypothesis is that better results can be achieved in case a rotating hinge design (RHK) is used. The reason could be that RHK designs allow for much more aggressive capsuloligament debridement and therefore more adequate fibrosis removal, while securing optimal implant stability, tibiofemoral rotational freedom, and flexion-extension space stability. The purpose of our study was to investigate in our database whether this hypothesis is correct.

METHODS

Retrospectively, 40 patients with the defined range of knee motion were identified. Patients with underlying mechanical malalignment, component malposition, soft-tissue imbalance or infections were excluded. Twenty-two patients received a hinged-type prosthetic device (18 Zimmer RHK, four Stryker RHK) and 18 patients received a less constrained condylar type prosthetic device (17 Legion CCK, one Vanguard CCK).

RESULTS

Preoperative data were similar for RHK as CCK-type implants except for knee pain score, which was significantly worse for the RHK group (36 vs 44, p = 0.049). At two years of follow-up, compared to CCK, the RHK group demonstrated significantly better postoperative results for knee function scores (68.9 vs 54.2, p = 0.0015), knee function improvement (22.8 vs 4.8, p = 0.0015), knee pain improvement (26.4 vs 9.4, p = 0.0050), greater maximal flexion (99.9° vs 81.4°, p = 0.0005), better maximal extension (-1.9° vs -6.2°, p = 0.0447), greater flexion gain (35.8° vs 14.2°, p = 0.0002), and greater extension gain (8.6° vs 2.0°, p = 0.0083).

CONCLUSION

Our data show that revision arthroplasty of the stiff knee using a rotating hinged device can provide excellent results in selected cases. To date, this is the first study to describe the difference in outcome between revision total knee arthroplasty for idiopathic arthrofibrosis using a hinged or a constrained condylar knee device.

Improved clinical outcomes after revision arthroplasty with a hinged implant for severely stiff total knee arthroplasty

PURPOSE

Management of the severely stiff total knee arthroplasty (TKA) is challenging, with the outcome of revision arthroplasty being inferior compared to the outcome for other indications. The aim of this study was to analyse the outcome after revision TKA with hinged-type implants for severely stiff TKA [range of motion (ROM) ≤ 70°] at 2 years.

METHODS

A cohort of 38 patients with a hinged-type revision TKA (Waldemar Link or RT-Plus) and preoperative ROM ≤ 70° were selected from a prospectively collected database. ROM, visual analogue scale (VAS) for pain and satisfaction and Knee Society Score (KSS) were obtained preoperatively and at 3 months, 1 year and 2 years. Pre- and postoperative outcome were compared at 2 years.

RESULTS

There was a significant increase in ROM and KSS. VAS pain scores did not differ significantly. The median ROM at 2 years was 90° (range 50°-125°) with a median gain of 45° (range 5°-105°). Median VAS pain was 28.5 (range 0-96) points and median VAS satisfaction was 72 (range 0-100) points at 2 years. Twelve patients suffered a complication. Recurrent stiff knee was the most frequently reported complication (n = 5).

CONCLUSIONS

Hinged-type revision TKA following a severely stiff TKA renders a significant, although moderate, clinical improvement at 2 years.

LEVEL OF EVIDENCE

Retrospective case series. Level IV.

Increased symptoms of stiffness 1 year after total knee arthroplasty are associated with a worse functional outcome and lower rate of patient satisfaction

PURPOSE

Symptoms of stiffness after total knee arthroplasty (TKA) cause significant morbidity, but there is limited data to facilitate identification of those most at risk after surgery. Stratifying risk can aid earlier directed treatment options.

METHODS

A retrospective cohort consisting of 2589 patients undergoing a primary TKA was identified from an established arthroplasty database. Patient demographics, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and short form (SF) 12 scores were collected pre-operatively and 1 year post-operatively. In addition, patient satisfaction was assessed for 1 year. Patients with a worse WOMAC stiffness score in 1 year were defined as the "increased" stiffness group and the other cohort as the non-stiffness group.

RESULTS

At 1 year after surgery 129 (5%) patients had a significant increase in their stiffness symptoms (20%, 95% confidence interval (CI) 17.9-22.0, p < 0.001), and had significantly (all p < 0.001) less of an improvement in their pain, function and total WOMAC scores, and SF-12 scores compared to the non-stiffness group (n = 2460). Patient satisfaction was significantly lower (odds ratio (OR) 0.178, CI 0.121 to 0.262, p < 0.001) for the increased stiffness group. Logistic regression analysis identified male gender (OR 1.66, p = 0.02), lung disease (OR 2.06, p = 0.002), diabetes (OR 1.82, p = 0.02), back pain (OR 1.81, p = 0.005), and a pre-operative stiffness score of 44 or more (OR 5.79, p < 0.001) were significantly predictive of increased stiffness.

CONCLUSION

Patients with increased symptoms of stiffness after TKA have a worse functional outcome and a lower rate of patient satisfaction, and patients at risk of being in this group should be informed pre-operatively.

LEVEL OF EVIDENCE

Retrospective prognostic study, Level III.

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.

Outcomes indicators and a risk classification system for spinal manipulation under anesthesia: a narrative review and proposal

Over a period of decades chiropractors have utilized spinal manipulation under anesthesia (SMUA) to treat chronic back and neck pain. As an advanced form of manual therapy, SMUA is reserved for the patient whose condition has proven refractory to office-based manipulation and other modes of conservative care. Historically, the protocols and guidelines put forth by chiropractic MUA proponents have served as the clinical compass for directing MUA practice. With many authors and MUA advocates having focused primarily on anticipated benefit, the published literature contains no resource dedicated to treatment precautions and contraindications. Also absent from current relevant literature is acknowledgement or guidance on the preliminary evidence that may predict poor clinical outcomes with SMUA. This review considers risk and unfavorable outcomes indicators in therapeutic decision making for spinal manipulation under anesthesia. A new risk classification system is proposed that identifies patient safety and quality of care interests for a procedure that remains without higher-level research evidence. A scale which categorizes risk and outcome potential for SMUA is offered for the chiropractic clinician, which aims to elevate the standard of care and improve patient selection through the incorporation of specific indices from existing medical literature.