Gait kinematics and knee stability 10-years following posterior-stabilised total knee arthroplasty comparable to healthy adults >55.

PURPOSE: The purpose of this study was to compare the long-term objective biomechanical and functional parameters of a high-flexion total knee arthroplasty (TKA) design against healthy older adults to determine whether knee biomechanics are comparable in both populations. METHODS: One cohort of patients with a primary TKA, and a cohort of healthy adults over 55 years old with no musculoskeletal deficits or arthritis participated. Bilateral knee range of motion (RoM) was assessed with a goniometer, and gait patterns were analysed with a three-dimensional-motion capture system. An arthrometer quantified the anterior-posterior laxity of each knee. Statistical analyses were performed in SPSS software (α = 0.05). RESULTS: Twenty-three knees were replaced in 20 patients. At 9.8 ± 3.1 years postoperatively, patients' knees had a statistically significantly poorer RoM than healthy controls' knees (n = 23) due to limited flexion; p < 0.0001. Patients also failed to achieve the same degree of knee flexion as controls during downhill gait. No kinematic differences were observed during mid-flexion in level nor downhill gait; a state that has been associated with instability (p = 0.614; not significant [n.s]). There were no differences between groups in knee laxity (n.s). CONCLUSION: Patients in this study had similar gait patterns to healthy older adults during mid-flexion and were no more likely than the healthy controls to exhibit anterior-posterior translation of the knee > 7 mm; a known risk factor of instability. However, the knee flexion range was poorer. This likely led to bilateral pathological knee flexion patterns during downhill gait. LEVEL OF EVIDENCE: Level III.

The First Report of the International Cartilage Regeneration and Joint Preservation Society's Global Registry.

OBJECTIVE: The International Cartilage Regeneration and Joint Preservation Society's (ICRS's) global registry, aims to be the best source of information for patients and an unbiased resource of evidence-based medicine for scientists and clinicians working to help those unfortunate enough to suffer the pain and disability associated with articular cartilage lesions. This article constitutes the scientific summary of the reports' main findings. DESIGN: The article outlines the historical precedents in the development of orthopedic registries from the earliest tumor registries, then local arthroplasty databases that led ultimately to international collaborations between national arthroplasty and soft tissue registries. The ICRS global cartilage registry was designed from the outset as a GDPR (General Data Protection Regulation) compliant, multilingual, multinational cooperative system. It is a web-based user-friendly, live in 11 languages by end 2019, which can be accessed via https://cartilage.org/society/icrs-patient-registry/. Patients and clinicians enter data by smartphone, tablet, or computer on any knee cartilage regeneration and joint preservation treatment, including the use of focal arthroplasty. Knee Injury and Osteoarthritis Outcome Score and Kujala patient-reported outcome measures are collected preoperatively, 6 months, 12 months, and annually for ten years thereafter. EQ-5D data collection will allow cost-effectiveness analysis. Strengths, weaknesses, and future plans are discussed. RESULTS: Since inception the registry has 264 users across 50 countries. Major findings are presented and discussed, while the entire first ICRS global registry report is available at https://cartilage.org/society/icrs-patient-registry/registry-annual-reports/. Conclusion. A measure of the maturity of any registry is the publication of its findings in the peer reviewed literature. With the publication of its first report, the ICRS global registry has achieved that milestone.

Cell Viability in Arthroscopic Versus Open Autologous Chondrocyte Implantation.

BACKGROUND: Autologous chondrocyte implantation (ACI) is an effective method of repair of articular cartilage defects. It is a 2-stage operation, with the second stage most commonly performed via mini-arthrotomy. Arthroscopic ACI is gaining popularity, as it is less invasive and may accelerate early rehabilitation. However, handling and manipulation of the implant have been shown to cause chondrocyte cell death. PURPOSE: To assess the number and viability of cells delivered via an open versus arthroscopic approach in ACI surgery. STUDY DESIGN: Controlled laboratory study. METHODS: Sixteen ACI surgeries were performed on young cadaveric knees by 2 experienced surgeons: 8 via mini-arthrotomy and 8 arthroscopically. Live and dead cells were stained and counted on implants after surgery. The cell number and viability were assessed using confocal laser scanning microscopy. Surgery was timed from knife to skin until the end of cycling the knee 10 times after implantation of the cell-membrane construct. RESULTS: On receipt of cell membranes after transportation from the laboratory, ≥92% of the cells were viable. There were significantly more remaining cells (8.47E+07 arthroscopic vs 1.41E+08 open; P < .001) and 16 times more viable cells (3.62% arthroscopic vs 37.34% open; P < .001) on the implants when they were inserted via mini-open surgery compared with the arthroscopic technique. Open surgery was of a significantly shorter duration (6 vs 32 minutes; P < .001). CONCLUSION: In this study, there were significantly more viable cells on the implant when ACI was performed via mini-arthrotomy compared with an arthroscopic technique. CLINICAL RELEVANCE: The viability of cells delivered for ACI via an arthroscopic approach was 16 times less than via an open approach. The mini-arthrotomy approach is recommended until long-term clinical comparative data are available.

The surgical management of symptomatic articular cartilage defects of the knee: Consensus statements from United Kingdom knee surgeons.

BACKGROUND: Symptomatic articular cartilage and osteochondral lesions in the knee are an important source of pain and disability, and may lead to osteoarthritis. There are several surgical treatments for the condition, with emerging data evaluating their clinical effectiveness and longer-term clinical outcome. Health care providers have challenged the indications for the use of expensive techniques and have been reluctant to authorize funding or reimbursement. METHODS: The UK Cartilage Consensus Meeting was convened, involving clinicians in the UK with experience in the treatment options, decision-making and evaluation of the literature on the subject. RESULTS: This paper reports the consensus of attendees regarding appropriate surgical options for managing articular cartilage defects in the knee, validated by a large cohort of surgeons in the UK who are active in the field of articular cartilage surgery. CONCLUSIONS: An evidence-based United Kingdom Consensus of 104 clinicians on the surgical management of symptomatic articular cartilage lesions of the knee. Several techniques may be suitable for small defects. Cell therapy has the best evidence-based outcomes for larger defects. Responsible innovation, pooled data collection and improvement in physical therapies are important. Surgeons should have access to the most appropriate evidence-based therapies for first-line treatment.

Device-length changes and implant function following surgical implantation of the KineSpring in cadaver knees.

INTRODUCTION: The KineSpring implant system has been shown to provide load reductions at the medial compartment of the knee, and has demonstrated clinical success in reducing pain and increasing function in patients with medial knee osteoarthritis. These results depend on the ability of the KineSpring to rotate, lengthen, and shorten to accommodate knee motions, and in response to knee position and loading. PURPOSE: The present study was undertaken to determine length changes of the implanted KineSpring in response to a range of knee positions, external knee loads, and placements by different orthopedic surgeons. MATERIALS AND METHODS: KineSpring system components were implanted in ten cadaver leg specimens by ten orthopedic surgeons, and absorber-length changes were measured under combined loading and in different positions of the knee. RESULTS AND CONCLUSION: Spring compression consistent with knee-load reduction, and device lengthening and shortening to accommodate knee loads and motions were seen. These confirm the functionality of the KineSpring when implanted medially to the knee.

Knee Osteochondritis Dissecans Treated by the AO Hook Fixation System: A Four Year Follow-Up of an Alternative Technique.

Surgical fixation is recommended for stable osteochondritis dissecans (OCD) lesions that have failed nonoperative management and for all unstable lesions. In this study we set out to describe and evaluate an alternative method of surgical fixation for such lesions. Five knees with unstable OCD lesions in four male adolescent patients with open physes were treated with the AO Hook Fixation System. The outcome was evaluated both clinically and with three separate outcome systems (IKDC 2000, KOOS, Lysholm) at one and a mean four year follow-up. We demonstrated excellent clinical results in all patients. At four years, all scoring systems demonstrated statistically significant improvement when compared to the preoperative status. Our study suggests that the AO Hook Fixation System is an alternative method of surgical intervention with comparable medium term results with other existing modes of fixation and the added biomechanical advantage of the absence of distracting forces during hardware removal.

Medium-term (5-year) comparison of the functional outcomes of combined anterior cruciate ligament and posterolateral corner reconstruction compared with isolated anterior cruciate ligament reconstruction.

PURPOSE: To present a 5-year comparison of the functional outcomes of combined anterior cruciate ligament (ACL) and posterolateral corner (PLC) reconstruction with those of isolated ACL reconstruction. METHODS: All patients were reviewed clinically and completed knee function questionnaires prospectively, by use of the International Knee Documentation Committee (IKDC) 2000, Knee Injury and Osteoarthritis Outcome Score (KOOS), and Lysholm scoring systems, preoperatively and at 1, 2, and 5 years postoperatively. Patients who underwent combined ACL-PLC reconstruction were identified and reviewed. These patients had intact lateral collateral ligaments. A comparison group was created from a group of patients who underwent isolated ACL reconstruction. The ACL group was selected to have the same profile with regard to age, sex, and meniscal procedure. RESULTS: There were 25 patients in the ACL-PLC group and 100 in the ACL group. All patients underwent restoration of their PLC function as shown on dial testing. The preoperative values for all KOOS measures and the Lysholm score were significantly lower in the ACL-PLC group than in the ACL group (P < .001). The IKDC score was not significantly different. All knee scores showed a significant improvement in both groups postoperatively at 1, 2, and 5 years (P < .001). At 5 years, the KOOS symptoms subscore (P < .001), KOOS pain subscore (P < .001), KOOS sports subscore (P < .001), KOOS quality-of-life subscore (P < .05), KOOS activities-of-daily living subscore (P < .001), aggregate score for all KOOS parameters (P < .001), and Lysholm score (P < .001) were significantly lower in the ACL-PLC group than in the ACL group. At 5 years, the IKDC scores were not significantly different. All patients in the ACL-PLC group resumed preinjury employment, and 23 of 25 had resumed sports. CONCLUSIONS: Combined ACL-PLC injuries have greater morbidity than isolated ACL injuries. However, return to work and sporting activity is possible in most cases after combined ACL-PLC reconstruction. The KOOS for sport outcomes suggests that sports were resumed at lower functional levels. LEVEL OF EVIDENCE: Level III, case-control study.

A prospective study to assess the outcomes of revision anterior cruciate ligament reconstruction.

PURPOSE: Continuously increasing numbers of primary anterior cruciate ligament (ACL) reconstructions invites a parallel increase in graft failures and need for revision ACL reconstruction surgery. High failure rates has previously stigmatised the revision surgery. We performed this study using multiple outcome measures together with clinical examination to offer a full assessment of the outcomes of this procedure. METHODS: Twenty patients, with mean age of 29.4 years (17-50 years), were included in this study prior to their revision ACL reconstruction surgery. All patients were followed prospectively collecting the Knee injury and Osteoarthritis Outcome (KOOS), International Knee Documentation Committee (IKDC) and Tegner-Lysholm scores pre- and post-operatively together with clinical assessment of the antero-posterior knee laxity. RESULTS: After a mean follow up interval of 30 months (16-60 months) significant post-operative improvement of IKDC, Tegner-Lysholm scores and knee antero-posterior laxity together with the Symptoms, Activities of Daily Living (ADL) and Quality of Life (QOL) components of the KOOS score was noticed (P < 0.05). However, there was no similar improvement in pain and sports components of the KOOS score (P > 0.05). There was no difference in the outcomes of different graft types. CONCLUSION: Good outcomes of revision ACL reconstruction surgery are achievable. The use of different graft types did not affect the outcome of the procedure. Most of the patients opted to less aggressive sports participation after the revision procedure.

Functional outcome of primary hamstring anterior cruciate ligament reconstruction in patients with different body mass index classes.

PURPOSE: We compared functional outcomes after primary hamstring-graft anterior cruciate ligament (ACL) reconstruction in patients with different body mass index (BMI) classes. METHODS: Functional outcomes after ACL reconstruction were measured using the Knee Injury and Osteoarthritis Outcome Score (KOOS) and the Lysholm score. The procedures were carried out by a single surgeon between 2001 and 2009 in 2 groups of patients with different BMI classes: a normal-BMI group (BMI 18.5 to 24.9) and a high-BMI group (BMI ≥ 25), with a minimum of 2 years' follow-up. Rolimeter readings for ligament laxity as well as complications between the 2 groups were also analyzed. RESULTS: A total of 92 patients were reviewed, with the normal-BMI group consisting of 49 patients, whereas there were 43 patients in the high-BMI group. There were no significant differences between the groups in any of the preoperative and postoperative scores or ligament laxity. Both groups showed comparable clinically significant improvement in their postoperative scores compared with their preoperative scores. Patients in the high-BMI group had a slightly increased postoperative complication rate when compared with the normal-BMI group. CONCLUSIONS: Primary hamstring ACL reconstruction is an effective treatment option in patients irrespective of preoperative BMI. High BMI does not adversely affect functional outcomes as measured by the KOOS and Lysholm scores up to and at 2 years postoperatively, and these patients benefit in a manner comparable to that of patients with normal BMI. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Dysfunction of the posterior cruciate ligament in total knee arthroplasty.

PURPOSE: Total knee arthroplasty (TKA) is typically carried out either with retention (CR) of the posterior cruciate ligament (PCL) or with sacrifice of this ligament and implantation of a posterior stabilised (PS) prosthesis. This paper investigates a comparison of PCL function in knees treated for osteoarthritis with TKA where the PCL is preserved to those knees treated with TKA and posterior stabilisation. METHODS: One hundred and sixty-eight patients (232 knees) who had undergone TKA with either a PS or CR implant were included in the study. Clinical assessment included antero-posterior (AP) laxity and posterior sag assessment with an arthrometer. RESULTS: The mean AP laxity at 90° of flexion for CR TKAs was 6.5 mm (±3.1) and was the same [6.5 mm (±2.4)] as in the PS group. However, 56% of the PCL-preserved knees had a posterior sag of over 3 mm compared to 18% of the knees in the PS group. The American Knee Society Scores for either group showed that, although the mean function score was the same, the knee score was superior in the PS group (77 vs. 84). The range of motion was also superior in the PS group (111° vs. 105°). CONCLUSION: The use of the PS prosthesis for TKA provides a more predictable outcome with regard to posterior sag and a better maximum flexion than a CR implant.

Total hip arthroplasty and the golfer: a study of participation and performance before and after surgery for osteoarthritis.

Many patients who undergo total hip arthroplasty still have a high level of activity. A popular low-intensity exercise in this patient group is golf. This study sought to investigate the group of patients who have had a hip arthroplasty procedure and who list golf as one of their pastimes, assessing the impact of surgery on their ability to participate in and perform at the game. Seven hundred fifty consecutive patients who had undergone total hip arthroplasty were sent questionnaires relating to their golfing habits. There was no significant change from their predisease state to their 1-year postoperative golf performance and level of participation. Harris hip scores were significantly higher for the golfing population both preoperatively and at all stages of follow-up.