A limited number of investigations with conflicting results have described perivascular lymphocytic infiltration (PVLI) in the setting of total knee arthroplasty (TKA). The purpose of this study was to determine if PVLI found in TKAs at the time of aseptic revision surgery was associated with worse clinical outcomes and survivorship. A retrospective review was conducted on 617 patients who underwent aseptic TKA revision who had histological analysis for PVLI at the time of surgery. Clinical and radiological data were obtained pre- and postoperatively, six weeks postoperatively, and then every year thereafter.Aims
Methods
The purpose is to determine the non-inferiority of a smartphone-based exercise educational care management system after primary knee arthroplasty compared with a traditional in-person physiotherapy rehabilitation model. A multicentre prospective randomized controlled trial was conducted evaluating the use of a smartphone-based care management system for primary total knee arthroplasty (TKA) and partial knee arthroplasty (PKA). Patients in the control group (n = 244) received the respective institution’s standard of care with formal physiotherapy. The treatment group (n = 208) were provided a smartwatch and smartphone application. Early outcomes assessed included 90-day knee range of movement, EuroQoL five-dimension five-level score, Knee Injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS JR) score, 30-day single leg stance (SLS) time, Time up and Go (TUG) time, and need for manipulation under anaesthesia (MUA).Aims
Methods
The purpose of this study is to evaluate the early perioperative outcomes after primary knee arthroplasty with the use of a smartphone-based exercise and educational platform compared to a standard of care control group. A multicenter prospective randomized control trial was conducted evaluating the use of the mymobility smartphone-based care platform for primary total knee arthroplasty (TKA) and unicondylar knee arthroplasty (UKA). Patients in the control group (224 patients) received the respective institution's standard of care typically with formal physical therapy. Those randomized to mymobility treatment group (192 patients) were provided an Apple Watch and mymobility smartphone application. The treatment group was not initially prescribed physical therapy, but could if their surgeon determined it necessary. Early outcomes assessed included 90-day knee range of motion, KOOS Jr scores, 30-day single leg stance (SLS) time, Time up and Go (TUG) time and need for manipulation under anesthesia (MUA). There was no significant difference in age, BMI or gender between groups.Background
Methods
A limited number of investigations with conflicting results have described perivascular lymphocytic infiltration (PVLI) in the setting of total knee arthroplasty. The purpose of this study was to determine if PVLI found in total knee replacements at the time of aseptic revision surgery was associated with worse clinical outcomes and survivorship. A retrospective review was conducted on 617 patients that underwent aseptic total knee arthroplasty revision who had histologic analysis for PVLI at the time of surgery. Clinical and radiographic data was obtained pre and postoperatively, 6 weeks post operatively, and then every year thereafter.Background
Methods
A smartphone-based care platform allows a customizable educational and exercise interface with patients, allowing many to recover after surgery without the need for formal physical therapy (PT). Furthermore, advances in wearable technology to monitor physical activity (PA) provides patients and physicians quantifiable metrics of the patient's recovery. The purpose of this study is to determine the feasibility of a smartphone-based exercise educational platform after primary knee arthroplasty as well as identifying factors that may predict the need for formal physical therapy. This study is part of a multi-institution, prospective study of patients after primary total knee arthroplasty (TKA) and partial knee arthroplasty (PKA) enrolled in a smartphone with smartwatch-based episode of care platform that recorded multimodal PA (steps, kcal, stairs). Postoperatively, all patients initially followed the smartphone-based exercise program. At the surgeon's discretion, patients were prescribed therapy if needed. The outcome of this study was the need for PT outside the app-based exercise program as well as time to return to preoperative step count. Variables assessed were preoperative weekly step counts (steps/day), weekly postoperative activity level (weekly step count compared to preoperative level), compliance with the exercise program (>75% completion) and patient demographic data including gender, age, BMI and narcotic use. One hundred eighty-eight patients were included in analysis: 45 PKA (24%) and 143 TKA (76%). Step count data was available on 135 patients and physical therapy data on 174.Introduction
Methods
The purpose of this multi-center, randomized clinical trial was to compare static and articulating spacers in the treatment of PJI complicating total knee arthroplasty TKA. 68 Patients treated with two-stage exchange arthroplasty were randomized to either a static (32 patients) or an articulating (36 patients) spacer. A power analysis determined that 28 patients per group were necessary to detect a 13º difference in range of motion between groups. Six patients were excluded after randomization, six died, and seven were lost to follow-up prior to two years.Background
Methods
Patients are often cautioned against a high level of activity following knee arthroplasty. The purpose of this study is to report on implant survivorship and outcomes of high activity patients compared to low activity patients after TKA. We identified 1611 patients (2038 knees) who underwent TKA with 5-year minimum follow-up. Patients were divided in two groups: Low activity (LA) (UCLA ≤5) and high activity (HA) (UCLA ≥ 6). Pre-and postoperative ROM, Knee Society scores, complications and reoperations were evaluated.Introduction
Methods
Modern implant systems offer a variety of options to address the posterior cruciate ligament (PCL) and afford stability in primary total knee arthroplasty (TKA). One system has three bearing options for cruciate retaining (CR) TKA: standard CR bearing (CR-S) with 3° posterior slope and no posterior lip; CR lipped bearing (CR-L) with no slope and small posterior lip, and deep-dished anterior stabilized bearing (CR-AS) with large anterior build-up to compensates for deficient or lax PCL. We previously reported on 1940 patients (2449 CR-TKA) at early follow-up comparing these three CR bearings and found CR-AS bearings had greater improvement in ROM and lower rate of manipulation despite their use in patients with greater preoperative deformity and lower ROM. The purpose of this study was to review a broader series by a single surgeon-designer with minimum 2-year follow-up to determine if there were differences between bearing types in terms of clinical outcomes and survival. From 2003 to 2014, 3348 patients (4500 knees) underwent primary CR-TKA and were available for review with minimum 2-year follow-up. An algorithmic approach to constraint was employed, choosing the least amount necessary to afford stability. Bearings used were 3883 CR-S (86%), 256 CR-L (6%), and 361 CR-AS (8%). CR-S bearings were used in patients with less preoperative tibiofemoral deformity (p=0.0316), less flexion contracture (p<0.0001), and better ROM (p<0.0001), but more mediolateral instability (p<0.0001) than CR-AS bearings.Introduction
Methods
Lateral partial knee replacement is indicated as an alternative to total knee replacement for isolated end stage lateral compartment degenerative joint disease. The purpose of this study is to report the surgical technique and clinical results of a large series of lateral partial knee replacements from two institutions. A retrospective review identified 205 lateral unicompartmental arthroplasty procedures performed in two practices over a six-year period (Aug 2011 – June 2017). Patients indicated for surgery met specific preoperative clinical and radiographic criteria confirming lateral compartment arthritic disease with a correctable deformity, intact full-thickness medial cartilage, competent anterior cruciate ligament, and minimal disease in the patellofemoral compartment. A single cemented fixed bearing tibial component design was used in all cases specifically designed for lateral compartment anatomy.Intro/Purpose
Methods
An evidence-based radiographic Decision Aid for meniscal-bearing
unicompartmental knee arthroplasty (UKA) has been developed and
this study investigates its performance at an independent centre. Pre-operative radiographs, including stress views, from a consecutive
cohort of 550 knees undergoing arthroplasty (UKA or total knee arthroplasty;
TKA) by a single-surgeon were assessed. Suitability for UKA was
determined using the Decision Aid, with the assessor blinded to
treatment received, and compared with actual treatment received, which
was determined by an experienced UKA surgeon based on history, examination,
radiographic assessment including stress radiographs, and intra-operative
assessment in line with the recommended indications as described
in the literature.Aims
Patients and Methods
Since redesign of the Oxford phase III mobile-bearing unicompartmental
knee arthroplasty (UKA) femoral component to a twin-peg design,
there has not been a direct comparison to total knee arthroplasty
(TKA). Thus, we explored differences between the two cohorts. A total of 168 patients (201 knees) underwent medial UKA with
the Oxford Partial Knee Twin-Peg. These patients were compared with
a randomly selected group of 177 patients (189 knees) with primary
Vanguard TKA. Patient demographics, Knee Society (KS) scores and
range of movement (ROM) were compared between the two cohorts. Additionally,
revision, re-operation and manipulation under anaesthesia rates
were analysed.Aims
Patients and Methods
Previous studies of failure mechanisms leading
to revision total knee replacement (TKR) performed between 1986 and
2000 determined that many failed early, with a disproportionate
amount accounted for by infection and implant-associated factors
including wear, loosening and instability. Since then, efforts have
been made to improve implant performance and instruct surgeons in
best practice. Recently our centre participated in a multi-centre evaluation
of 844 revision TKRs from 2010 to 2011. The purpose was to report
a detailed analysis of failure mechanisms over time and to see if
failure modes have changed over the past 10 to 15 years. Aseptic
loosening was the predominant mechanism of failure (31.2%), followed
by instability (18.7%), infection (16.2%), polyethylene wear (10.0%),
arthrofibrosis (6.9%) and malalignment (6.6%). The mean time to
failure was 5.9 years (ten days to 31 years), 35.3% of all revisions
occurred at less than two years, and 60.2% in the first five years.
With improvements in implant and polyethylene manufacture, polyethylene
wear is no longer a leading cause of failure. Early mechanisms of
failure are primarily technical errors. In addition to improving
implant longevity, industry and surgeons must work together to decrease
these technical errors. All reports on failure of TKR contain patients
with unexplained pain who not infrequently have unmet expectations.
Surgeons must work to achieve realistic patient expectations pre-operatively,
and therefore, improve patient satisfaction post-operatively. Cite this article:
Debate has raged over whether a cruciate retaining
(CR) or a posterior stabilised (PS) total knee replacement (TKR) provides
a better range of movement (ROM) for patients. Various sub-sets
of CR design are frequently lumped together when comparing outcomes.
Additionally, multiple factors have been proven to influence the
rate of manipulation under anaesthetic (MUA) following TKR. The
purpose of this study was to determine whether different CR bearing
insert designs provide better ROM or different MUA rates. All primary
TKRs performed by two surgeons between March 2006 and March 2009
were reviewed and 2449 CR-TKRs were identified. The same CR femoral
component, instrumentation, and tibial base plate were consistently
used. In 1334 TKRs a CR tibial insert with 3° posterior slope and
no posterior lip was used (CR-S). In 803 there was an insert with
no slope and a small posterior lip (CR-L) and in 312 knees the posterior
cruciate ligament (PCL) was either resected or lax and a deep-dish,
anterior stabilised insert was used (CR-AS). More CR-AS inserts
were used in patients with less pre-operative ROM and greater pre-operative
tibiofemoral deformity and flexion contracture (p <
0.05). The
mean improvement in ROM was highest for the CR-AS inserts (5.9°
(-40° to 55°) Cite this article:
