The Cost of Stiffness After Total Knee Arthroplasty

A Lack of Generalizability-Total Knee Demographics in the Active Duty Population

INTRODUCTION

Age and sex are known demographic risk factors for requiring revision surgery following primary total knee arthroplasty (TKA). Military service members are a unique population with barriers to long-term follow up after surgery. This study aims to compare demographic data between active duty military personnel and a nationwide sample to identify differences that may impact clinical and economic outcomes.

METHODS

A retrospective observational analysis was performed using the Military Health System Data Repository (MDR) and the National Surgical Quality Improvement Program (NSQIP). Databases were queried for patients undergoing primary TKA between January 1, 2015 and December 31, 2020. The MDR was queried for demographic data including age, sex, duty status, facility type, geographic region, history of prior military deployment, history of deployment-related health condition, branch of military service, and military rank. National Surgical Quality Improvement Program was queried for age and sex. Median age between populations was compared with the Mann-Whitney U test, and gender was compared with a chi-squared test.

RESULTS

During the study period, 2,094 primary TKA patients were identified from the MDR, and 357,865 TKA patients were identified from the NSQIP database. Military TKA patients were 79.4% male with a median age of 49.0, and NSQIP TKA patients were 38.9% were male, with a median age of 67. Military TKA patients were significantly more likely to be male (P < .001) and younger (P < .001).

CONCLUSION

Patients undergoing TKA in the military are younger and more likely to be male compared to national trends. Current evidence suggests these factors may place them at a significant revision risk in the future. The application of quality metrics based on nationwide demographics may not be applicable to military members within the Military Health System.

Multicenter, prospective cohort study: immediate postoperative gains in active range of motion following robotic-assisted total knee replacement compared to a propensity-matched control using manual instrumentation

BACKGROUND

Range of motion (ROM) following total knee replacement (TKR) has been associated with patient satisfaction and knee function, and is also an early indicator of a successful procedure. Robotic-assisted TKR (raTKR) is considered to reproduce more precise resections, and, as a result, may be associated with improved early patient satisfaction compared to manual TKR (mTKR). The purpose of this study was to evaluate the early postoperative active ROM (aROM) between raTKR and mTKR.

METHODS

A total of 216 mTKR patients were propensity-matched, in terms of age, gender, comorbidities, and BMI, to 216 raTKR cases. Intraoperative and immediate postoperative adverse events were collected. Knee flexion and extension aROM were measured preoperatively and at one- and three months after operation.

RESULTS

Changes in flexion aROM were significantly greater in raTKR vs. mTKR at one- (6.9°, 95% CI: 3.5, 10.4°) and three months (4.9°, 95% CI: 2.1, 7.7°). Flexion aROM was greater at three postoperative months compared to preoperative aROM only in the raTKR group, and raTKR patients had higher odds of achieving ≥ 90° of flexion at one month after operation (OR: 2.15, 95% CI: 1.16, 3.99). There were no significant differences between groups in intraoperative (P > 0.999) or postoperative adverse events.

CONCLUSIONS

Compared with mTKR, raTKR resulted  in less loss of aROM immediately after operation and a faster recovery of aROM within three months after operation.

TRIAL REGISTRATION

Clinicaltrials.gov (NCT# 03737149).

Arthroscopic Procedures Are Performed in 5% of Patients With Knee Osteoarthritis 1 Year Preceding Total Knee Arthroplasty and Are Associated With Increased Stiffness and Increased Costs

Purpose

To describe the different types of arthroscopic procedures that patients undergo in the year prior to total knee arthroplasty (TKA), reveal the cost associated with these procedures, and understand the relationship between preoperative arthroscopy and clinical outcomes after TKA.

Methods

An observational cohort study was conducted using the IBM Watson Health MarketScan databases. Patients with knee osteoarthritis who underwent unilateral isolated primary TKA between January 1, 2018, and September 30, 2019, were included. Knee arthroscopic procedures performed in the 1-year period before a primary TKA was identified. The primary outcomes of interest were cost of these procedures and the risk of 90-day postoperative complications.

Results

In total, 2,904 patients, representing 5.2% of the analyzed cohort, underwent arthroscopic procedures in the year prior to TKA. The most common procedure and diagnosis were meniscectomy and meniscal tear, respectively, with procedures performed an average of 7.2 ± 3.0 months before TKA. Average per patient costs were $9,716 ± $5,500 in the highest payment quartile vs $1,789 ± 636 in the lowest payment quartile. Patients with a history of arthroscopy were more likely to develop postoperative stiffness (P = .001), while no difference was found in the risk of 90-day periprosthetic joint infection (PJI).

Conclusions

Of the patients, 5.2% underwent knee arthroscopy in the year prior to TKA. While no association was seen with PJI risk, the costs associated with these procedures are high and may increase the overall cost of management of knee osteoarthritis.

Level of Evidence

Level III, retrospective comparative study.

Distal Femur Megaprostheses in Orthopedic Oncology: Evaluation of a Standardized Post-Operative Rehabilitation Protocol

BACKGROUND AND OBJECTIVES

Megaprostheses are the most used reconstructive approach for patients who have undergone massive resection of their distal femurs due to bone tumors. Although the literature about their outcomes has flourished in recent decades, to date, a consensus on rehabilitative treatment is yet to be established. In this study, we report on our experience with our latest standardized rehabilitation program, evaluating our results in a mid-to-long-term scenario.

MATERIALS AND METHODS

We evaluated the functional results of all our oncologic patients treated between 2016 and 2022 who could follow our standardized post-operative rehabilitative approach, consisting of progressive knee mobilization and early weight-bearing.

RESULTS

Sixteen cases were included in our study. The average duration of the patients' hospitalization was 12.2 days. A standing position was reached on average 4.1 days after surgery, while assisted walking was started 4.5 days after surgery. After a mean post-operative follow-up of 46.7 months, our patients' mean MSTS score was 23.2 (10-30). Our data suggest that the sooner patients could achieve a standing position (R = -0.609; p = 0.012) and start walking (R = -0.623; p = 0.010), the better their final functional outcomes regarding their MSTS scores.

CONCLUSIONS

Rehabilitation should be considered a pivotal factor in decreeing the success of distal femur megaprosthetic implants in long-surviving oncologic patients. Correct rehabilitation, focused on early mobilization and progressive weight-bearing, is crucial to maximizing the post-operative functional outcomes of these patients.