Introduction

Total hip arthroplasty (THA) candidates have received high doses of opioids within the perioperative period for the management of surgical pain. Healthcare systems have responded by improving opioid administration documentation and are now implementing opioid-sparing protocols (OSP) into THA integrated care pathways (ICP). Here we evaluate the effectiveness of a novel OSP in primary THA at out institution.

Introduction:

Total hip arthroplasty (THA) is extremely effective in treating debilitating arthritic conditions of the hip. With the many modular prosthetic designs available, surgeons can now precisely construct mechanical parameters such as femoral offset (FO). Although several studies have investigated relationships between offset choice and hip abductor strength, hip range of motion, and prosthetic wear rate, there is scarce data on the effect of FO on pain and functional outcomes following THA. The objective of this study was to assess the effect of restoring FO (within varying degrees compared to the contralateral non-diseased hip [CL]) on physical function, mental well-being, pain, and stiffness outcomes as measured by the Short Form 12 Health Survey (SF-12) and Western Ontario and McMaster University Osteoarthritis Index (WOMAC) at post-operative follow-up.

Introduction:

Unicompartmental knee arthroplasty (UKA) has been proven to be an effective treatment for degenerative joint disease confined to a single tibiofemoral compartment. Recently, UKAs have been performed with robotic-arm assistance (RAA) devices to build and improve upon previous computer-assisted navigation. As a pilot study, we have analyzed short term outcomes for a series of robotic-arm assisted medial UKAs and compared them to a comparable cohort of traditionally instrumented medial UKAs.

Not all patients receive enhanced mobility and return to comfortable, independent living after Total Hip Arthroplasty (THA). It would be beneficial to both surgeons and patients to be able to predict short term outcomes for THA. The purpose of this study was to investigate factors affecting the short term outcome of primary THA and develop a multivariate regression model that can predict such outcomes.

This was a prospective study of 101 patients, who underwent primary THA. All patients were followed for a minimum of 1 year. 12 independent variables, including age, gender, diagnosis, presence of preoperative comorbidities, BMI, preoperative WOMAC physical component (PC) score, type of anesthesia, type of fixation, surgical time, estimated blood loss, use of a postoperative drain, and length of stay were analyzed using correlation and multivariate regression analyses. Multivariate regression models were validated using an independent cohort.

Correlation analyses showed three variables significantly influence short term THA outcome. These include preoperative WOMAC PC score (PC) (p< 0.01), gender (G) (p= 0.01) and the presence of preoperative comorbidities (CMB) (p= 0.02). By multivariate regression analysis, the following regression model was obtained: Outcome = PC*0.45 −G*9 + CMB*8 + 62.

This model exhibited positive correlation (R2=.25) when compared to a separate cohort of 27 patients undergoing THA not included in the original equation derivation.

Our multivariate regression analysis has yielded statistical, multivariate confirmation or non-confirmation of common, predictive THA factors that have previously been reported in the literature. This study provides a concrete, statistically significant measure indicating that preoperative WOMAC PC score, gender, and the presence of preoperative comorbidities are predictive factors for short term primary THA outcome. Finally, our multivariate regression equation can be used to predict the general short term patient outcome following primary THA.

Introduction: Ranked as the second most common cause of long-term disability amongst American adults, osteoarthritis (OA) affects well over 60 million Americans per year. OA is one of the major contributors to health care-related economic cost in the US, which is generally considered unacceptably high when compared other Western industrialized nations.

Methods: Three hundred and thirty-five patients undergoing primary unilateral or bilateral total hip arthroplasty (THA), metal-on-metal hip resurfacing (MOMHR), total knee arthroplasty (TKA), or unicondylar knee arthroplasty (UKA) were offered voluntary participation in an one-on-one preoperative education session with a pre-operative educator. Length of stay (LOS) and in-patient costs was collected for patients who received individual pre-operative education. This was then compared to patients who chose not to participate in the education sessions using linear regression models.

Results: Patients who chose to participate enjoyed a significantly shorter LOS than those who did not receive education, controlling for age, sex, type of procedure, and number of co-morbid conditions (3.1 ± 1.1 vs. 4.5 ± 4.7; p< 0.01). THA patients participating in the preoperative education program exhibited a calculated cost savings of $861 per case over non-educated patients (p=0.06), while TKA patients participating in the program exhibited a statistically significant savings of $1,144 per case (p=0.02). This translated into a cost savings of $84,351 for 93 THA patients and $93,493 for 74 TKA patients at our institution, accounting for the cost of the patient educator. Of higher significant impact on cost savings was the number of co-morbid conditions for both THA (p=0.01) and TKA (p=0.01) patients. If applied in the national setting, national cost savings projections for a mean 0.84 day reduction in LOS for educated THA patients estimated a savings of nearly $800 million; a mean 0.56 day reduction for preoperatively educated TKA translated into a projected savings of $1.1 billion on the national scale.

Conclusion: Preoperative education in the setting of hip and knee arthroplasty is an important cost-savings tool for hospitals, Medicare and third party payers in this era of rising health care costs.

Purpose: Patients undergoing total knee arthroplasty (TKA) often experience a difficult recovery due to severe post-operative pain. Utilizing a multi-modal pain management protocol, a blinded, randomized, placebo-controlled study was designed to evaluate the efficacy of patient selected music on reducing perceived pain.

Method: Using a standardized intra-operative anesthetic protocol and postoperative pain management protocol, consented patients were randomized into either: 1) the interventional Music group (noise-reduction headphones, patient choice/classical music) or the control, Non-Music group (noise-reduction headphones only). Pain scores, aided by the Wong-Baker and Verbal Descriptor scales, were assessed via the Visual Analog Scale (VAS) at baseline and postoperatively at 3, 6, and 24 hours. A paired Student’s t-test was utilized to determine statistical significance, which was set at a p < 0.05.

Results: Thirty subjects were enrolled. At baseline, there were no statistical differences in mean pain between the study (2.29 ± 2.78) and the control (3.34 ± 2.67) groups (p = 0.19). Mean pain scores reported the Music group to have significantly less pain at 3 hours (1.49 ± 1.39 vs. 3.87 ± 3.44, p = 0.01), and at 24 hours (2.41 ± 1.67 vs. 4.03 ± 2.89, p=0.04).

Conclusion: Intraoperative music provides an inexpensive, non-invasive method of lowering perceived postoperative pain for patients undergoing a TKA. The results of this study offer a glimpse into how an alternative therapy or non-pharmacologic method can reduce postoperative pain. A larger-scale, higher powered trial may demonstrate how music could favorably affect secondary outcomes such as patient satisfaction, range of motion, and length of stay.

Introduction: Unicondylar knee arthroplasty (UKA) has seen a resurgence in the past decade. Perpetuation of this trend can only be supported through prospective demonstration of efficacy with validated outcomes measures.

Materials & Methods: Thirty-three consecutive cemented medial Miller-Galante UKA’s (Zimmer, Warsaw, IN) were performed in 32 patients (7 males/25 females; mean age of 67 ± 9 years). Average weight, height, and body mass index (BMI) of the patient population was 189 ± 31 lbs (Range, 145–293), 65 ± 4 in (range, 60–75), and 33 ± 5 BMI (range, 25–43), respectively. Average polyethylene thickness (as labelled) for this cohort was 8.3mm (range, 8–12mm). Outcomes were prospectively assessed via the SF-12, WOMAC, and Knee Society Score (KSS). No patients were lost to follow-up. Kaplan-Meier survivorship and Student’s t-test were performed using GraphPad Prism 4 software (GraphPad Software Inc., San Diego, CA).

Results: Minimum follow-up was 39 months with a mean follow up period of 49 (range, 39–59) months. One knee was converted at 6 months at another institution to a TKA. Kaplan-Meier survivorship analysis reported 97% survivorship at 59 months (95% CI). Of the 32 knees remaining, mean preoperative KSS and WOMAC pain scores improved significantly from 52 ± 7 (range, 37–67) to 89 ± 9 (range, 67–100) (p< 0.0001) and from 40 ± 22 (range, 0–80) to 93 ± 14 (range, 35–100) (p< 0.0001), respectively. Additionally, average SF-12 Physical Component scores significantly increased from 30 ± 7 (range, 18–51) at baseline to 49 ± 10 (range, 28–59) at time of follow-up (p< 0.0001). Overall stiffness and physical function assessed via the WOMAC index also exhibited statistically significant improvement, bettering from mean baseline scores of 54 ± 24 (range, 0–100) and 52 ± 19 (range, 25–87) to 84 ± 19 (range, 50–100, p< 0.0001) and 88 ± 15 (range, 44–100, p< 0.0001), respectively. No significant cement/bone interface radiolucencies were found upon thorough radiographic review at 3 years post UKA.

Discussion & Conclusion: The significant improvements observed in knee function & stiffness, and decreases in pain at a mean of 4 years after medial UKA are encouraging. Coinciding results from the physical component of the SF-12 assessment indicate reassurance of physical improvements regarding patient lifestyle. 97% survivorship in the short term would be discouraging if not for the specific circumstances of the sole conversion to TKA. This specific patient went against the advice of the operative surgeon and solicited services at an outside institution in conversion to a TKA despite markedly improved function (Pre-op/3 month post-op WOMAC and KSS of 30/75 and 60/91). Clinical and radiographic follow-up will continue in order to assess the long-term efficacy of medial UKA with the Miller-Galante prosthesis using strict patient selection criteria.

In May 2006, the US FDA approved the first type of metal-on-metal hip resurfacing (MOMHR) for distribution in the US because of promising survivorship achieved in Europe for patients with a diagnosis of primary osteoarthritis. No long-term US survivorship data currently exists for the Birmingham Hip Resurfacing (BHR) implant. The purpose of this study was to demonstrate early efficacy with validated outcome measures and survivorship comparable to total hip arthroplasty (THA).

A cohort of 79 consecutive MOMHR patients was compared to a similar cohort of 71 THA patients, controlling for age, gender and comorbidities. Mean f/u was 14.1±5 mos (range 12–24 mos). The mean age for the MOMHR group was 50±9 yrs, and mean body mass index (BMI) was 29±5. The THA group had a mean age of 52±9 yrs and a mean BMI of 30±6. Outcomes were prospectively assessed with the SF-12 and WOMAC.

For both groups, pre-op pain and function scores were similar. At 1 yr f/u, MOMHR showed significantly more improvement (p< 0.05) in stiffness, pain and physical function compared to the THA. The overall complication rate was 7% in the MOMHR group and 9% in the THA group. There were no instances of displaced femoral neck fracture, component loosening, dislocation or chronic deep infection in any patient in the MOMHR cohort.

These early results are promising, but longer-term follow-up is needed to properly compare MOMHR to THA which remains the current gold standard.