Background

The JOURNEY™ II Cruciate-Retaining Total Knee System (JIICR) and the JOURNEY™ II Bi-Cruciate Stabilized Total Knee System (JIIBCS) (both, Smith & Nephew, Memphis, TN, USA) are used for the treatment of end-stage degenerative knee arthritis. Belonging to the JOURNEY family of knee implants, the relatively new devices are designed to provide guided motion. Studies suggest that long-term outcomes of robotic-assisted navigation in total knee arthroplasty (TKA) are superior to the classical approach. This is the first report describing early postoperative outcomes of the NAVIO® robotic-assisted surgical navigation using the JOURNEY™ II family of knee implants.

The goals of a total knee arthroplasty include approximation of the function of a normal knee and achievement of balance post-surgery. Accurate bone preparation and the preservation of natural ligaments along with a functional knee design, holds the potential to provide a method of restoring close to normal function.

Although conventional knee arthroplasty is considered a successful intervention for end-stage osteoarthritis, some patients still experience reduced functionality and in some cases, require revision procedures. With conventional manual techniques, accurate alignment of the tibial component has been difficult to achieve. Even in the hands of skilled knee surgeons, outliers beyond 2 degrees of the desired alignment may occur in as many as 40%-60% of cases using conventional methods, and the range of component alignment varies considerably.

Similarly, for total knee replacement outliers beyond 2 degrees of the desired alignment may occur in as many as 15% of cases in the coronal plane, going up to 40% of unsatisfactory alignment in the sagittal plane.

Robotics-assisted arthroplasty has gained increasing popularity as orthopaedic surgeons aim to increase accuracy and precision of implant positioning. With advances in computer generated data, with image free data, surgeons have the ability to better predict and influence surgical outcomes. Based on planned implant position and soft tissue considerations, robotics-assisted systems can provide surgeons with virtual tools to make informed decisions for knee replacement, specific to the needs of the patient.

Here, for the first time in a live surgical setting, we assess the accuracy and technique of a novel imageless semiautonomous handheld robotic surgical technique in bi-cruciate retaining total knee arthroplasty (Navio, Smith and Nephew). The system supports image-free anatomic data collection, intraoperative surgical planning and execution of the plan using a combination of robotic burring and saw cut guides.

Introduction

Close to 30% of the surgical causes of readmission within 90 days post-total knee arthroplasty (TKA) and nearly half of those occurring in the first 2 years are caused by instability, arthrofibrosis, and malalignment, all of which may be addressed by improving knee balance. Furthermore, the recently launched Comprehensive Care for Joint Replacement (CJR) initiative mandates that any increase in post-acute care costs through 90-days post-discharge will come directly from the bundle payment paid to providers. Post-discharge costs, including the cost of readmissions for complications are one of the largest drivers of the 90-day cost of care. It is hypothesized that balanced knees post-TKA will lower the true provider costs within the 90-day bundle.

Introduction

Decreasing tissue damage and recovery time, while improving quality of life have been the focus of many approaches to total hip arthroplasty (THA). In this study, we compared two approaches, a tissue-sparing superior capsulotomy percutaneously assisted approach (SP) and the traditional posterior approach (TR), to address the question of whether the novel technique reduces tissue damage. The secondary aim of this study focused on the measurement technologies utilized to quantify the damage resulting from either SP or TR. Image J, BioQuant, and cellSens were the image analysis programs employed. Statistical validation and comparisons of results between all platforms were performed.

Introduction

Total hip replacement (THR) is one of the most successful orthopedic surgeries performed today. Long term success of THR has been well established, but there remains significant room to improve early outcomes (e.g. pain, length of hospital stay, readmissions). The surgical technique is a key variable affecting these early outcomes. The objective of the current study was to evaluate outcomes for over 1,000 consecutive THRs using the supercapsular percutaneously-assisted total hip (SuperPath) approach.

One out of every five total knee arthroplasty (TKA) recipients is unhappy with the outcome of their surgery. As the number of TKA candidates continues to increase, so, too, will the dissatisfied patient population. These statistics should not be acceptable to the surgeons, hospitals, and patients implicated in this elective procedure. There are many contributing factors to patient dissatisfaction, paramount among them being post-operative levels of functionality and pain. Therefore, in an attempt to increase function and decrease pain levels through soft-tissue management, sensor-assisted TKA outcomes were compared with manual TKA outcomes.

One hundred and fourteen primary TKA patients were evaluated: 57 sensor-assisted TKA patients; 57 manual TKA patients. All procedures were performed by the same surgeon. In order to reduce confounding variables, all patients were matched for: age, gender distribution, BMI, marital status, smoking proclivity, pre-operative ROM, pre-operative alignment, and employment status. Outcomes scores were captured pre-operatively, and at the 6-month interval, including Knee Society Score metrics and the Oxford score, as well as 6-month ROM. The sensor device used in this analysis is inserted into the tibial component, during the trialing, and displays loading values in the medial and lateral compartments (lbf.), and also displays the medial and lateral center of load location. In the sensor-assisted TKA group, balance was achieved for all patients, as previously described in literature.

There was a statistically significant rate of improvement, for all outcomes measures, in the sensor-assisted TKA group when compared with the manual group (Figure 1). In addition to rate of improvement, there was also a significant trend towards a significance in ROM in the sensor-assisted group, as a stand-alone dependent variable (P = 0.002).

By the 6-month follow-up interval, patients in receipt of a sensor-assisted TKA reported greater improvement in function and less pain than the patients in the manual TKA group. This data suggests that soft-tissue balance may contribute to faster recovery, as reported by the patient. Because pain and function play an integral role in patient satisfaction, further follow-up might yield higher satisfaction in the sensor-assisted patient group, which is consistent with previously published observations.

Introduction

The supercapsular percutaneously-assisted total hip (SuperPath) replacement surgical technique was developed as a hybrid of the supercapsular (SuperCap) and percutaneously-assisted total hip (PATH) approaches. The technique does not require any muscle release and preserves the external rotators with the objectives of reducing hospital length of stay, increasing the percentage of subjects discharged home, and decreasing complications (e.g. dislocation). The purpose of this study was to evaluate these perioperative outcomes associated with a large consecutive cohort of prospectively followed subjects.

The accuracy of cup position in total hip arthroplasty is essential for a satisfactory result as malpositioning increases the risk of complications including dislocation, high wear rate, loosening, squeaking, edge loading, impingement and ultimately failure.

We studied 173 patients in a single surgeon series of matched cohorts of patients who underwent total hip arthroplasty. Four separate groups were identified comprising of posterior approach +/− navigation and direct anterior approach +/− navigation.

We found a significant difference between the direct anterior navigated group and the posterior non-navigated group for both anteversion (p < 0.05, CI −3.86 to −1.73) and inclination (p < 0.05, CI −3.08 to −1.08). 72% of anterior navigated patients fell within 5° of the navigation software set target cup position of 45° inclination and 20° anteversion and 100% were within 10°. Only 30% of posterior non-navigated were within 5° of both anteversion and inclination and 73% were within 10°.

There was also a significant difference between the direct anterior navigated and non-navigated group with respect to anteversion only (p < 0.05, CI 1.50 to 1.30). There were no other significant differences between approaches +/− navigation.

The direct anterior approach allows ease of access to both anterior-superior iliac spines for navigation and a supine patient allows anteversion and inclination to be measured in the frontal plane. We conclude that the direct anterior approach with navigation improves accuracy of cup position compared to the conventional posterior approach without navigation.

Introduction

Squeaking is a potential problem of all hard on hard bearings yet it has been less frequently reported in metal-on-metal hips. We compared a cohort of 11 squeaking metal-on-metal hip resurfacings to individually matched controls, assessing cup inclination and anteversion between the groups to look for any differences.