Total knee arthroplasty in a group of patients less than 45 years of age

Early appearance of radiolucent lines around total knee arthroplasty in rheumatoid arthritis patients. How does it impact the aseptic failure rate and functional outcomes at 13 years of follow-up?

INTRODUCTION

Aseptic total knee arthroplasty (TKA) failure has been associated with radiolucent lines. This study aimed to determine the impact of the early appearance of radiolucent lines (linear images of 1, 2, or >2mm at the cement-bone interface) around the TKA on prosthetic survival and functional outcomes in rheumatoid arthritis (RA) patients during a 2-20 years follow-up.

METHODS

We retrospectively analyzed a consecutive series of RA patients treated with TKA between 2000 and 2011. We comparatively analyzed patients with and without radiolucent lines around implants. Clinical outcomes were assessed with the knee society score (KSS) collected before surgery, at years 2, 5, and 10, and at the last postoperative follow-up. The knee society roentgenographic evaluation system was used to analyze the impact of radiolucent lines around the implants at 1, 2, 5, and more than ten years of follow-up. The reoperation and prosthetic survival rates were calculated at the end of the follow-up.

RESULTS

The study series included 72 TKAs with a median follow-up of 13.2 years (range: 4.0-21.0), of which 16 (22.2%) had radiolucent lines. We did not observe aseptic failure, and prosthetic survival at the end of the study was 94.4% (n=68). The KSS improved significantly (p<0.001) between preoperative values at 2, 5, and 10 years and the end of follow-up, with no differences between patients with and without radiolucent lines.

CONCLUSIONS

Our study demonstrates that the early appearance of radiolucent lines around a TKA in RA patients does not significantly impact prosthetic survival or long-term functional outcomes at 13 years of follow-up.

Early appearance of radiolucent lines around total knee arthroplasty in rheumatoid arthritis patients. How does it impact the aseptic failure rate and functional outcomes at 13 years of follow-up?

INTRODUCTION

Aseptic total knee arthroplasty (TKA) failure has been associated with radiolucent lines. This study aimed to determine the impact of the early appearance of radiolucent lines (linear images of 1, 2, or > 2mm at the cement-bone interface) around the TKA on prosthetic survival and functional outcomes in rheumatoid arthritis (RA) patients during a 2-20 years follow-up.

METHODS

We retrospectively analyzed a consecutive series of RA patients treated with TKA between 2000 and 2011. We comparatively analyzed patients with and without radiolucent lines around implants. Clinical outcomes were assessed with the knee society score (KSS) collected before surgery, at years 2, 5, and 10, and at the last postoperative follow-up. The knee society roentgenographic evaluation system was used to analyze the impact of radiolucent lines around the implants at 1, 2, 5, and more than ten years of follow-up. The reoperation and prosthetic survival rates were calculated at the end of the follow-up.

RESULTS

The study series included 72 TKAs with a median follow-up of 13.2 years (range: 4.0-21.0), of which 16 (22.2%) had radiolucent lines. We did not observe aseptic failure, and prosthetic survival at the end of the study was 94.4% (n=68). The KSS improved significantly (p<0.001) between preoperative values at 2, 5, and 10 years and the end of follow-up, with no differences between patients with and without radiolucent lines.

CONCLUSIONS

Our study demonstrates that the early appearance of radiolucent lines around a TKA in RA patients does not significantly impact prosthetic survival or long-term functional outcomes at 13 years of follow-up.

Predictors of reoperation and survival experience for primary total knee arthroplasty in young patients with degenerative and inflammatory arthritis

INTRODUCTION

While total knee arthroplasty (TKA) is typically implemented in patients > 65 years old, young patients may need to undergo TKA for pain relief and functional improvement. Current data are limited by older cohorts and short-term survival rates. This study aimed to examine a large sample size of patients with degenerative and inflammatory conditions who underwent primary TKA at a young (≤ 40) age to identify predictors of reoperation, as well 15-year survivorship.

MATERIALS AND METHODS

A retrospective study was performed on 77 patients (92 surgeries) who underwent primary TKA at ≤ 40 years old, between January 1990 and January 2020. Patient charts were reviewed and a multivariable logistic regression model identified independent predictors of reoperation. Kaplan-Meier analysis was employed to build survival curves and log-rank tests analyzed survival between groups.

RESULTS

Of the 77 patients, the median age at the time of surgery was 35.7 years (IQR: 31.2-38.7) and median follow-up time was 6.88 years. Twenty-one (22.8%) primary TKAs underwent 24 reoperations, most commonly due to stiffness (n = 9, 32.1%) and infection (n = 13, 46.4%) more significantly in the OA group (p = 0.049). There were no independent predictors of reoperation in multivariable analysis, and 15-year revision-free survivorship after TKA did not differ by indication (77.3% for OA/PTOA vs. 96.7% for autoimmune, p = 0.09) or between ≤ 30 and 31-40 year age groups (94.7% vs. 83.6%, p = 0.55).

CONCLUSIONS

In this cohort of patients ≤ 40 years old, revision-free survival was comparable to that reported in the literature for older TKA patients with osteoarthritis/autoimmune conditions (81-94% at 15-years). Though nearly a quarter of TKAs required reoperation and causes of secondary surgery differed between degenerative and inflammatory arthritis patients, there were no significant predictors of increased reoperation rate. Very young patients ≤ 30 years old did not have an increased risk of revision compared to those aged 31-40 years.

Survivorship and Clinical Outcomes of Primary Total Knee Arthroplasty Performed in Patients 35 Years of Age and Younger

BACKGROUND

Total knee arthroplasties (TKAs) for patients aged ≤35 years are rare but necessary for patients who have diseases such as juvenile idiopathic arthritis, osteonecrosis, osteoarthritis, and rheumatoid arthritis. Few studies have examined the 10-year and 20-year survivorship and clinical outcomes of TKAs for young patients.

METHODS

A retrospective registry review identified 185 TKAs in 119 patients aged ≤ 35 years performed between 1985 and 2010 at a single institution. The primary outcome was implant survivorship free of revision. Patient-reported outcomes were assessed at 2 time points: 2011 to 2012 and 2018 to 2019. The average age was 26 years (range, 12 to 35). Mean follow-up was 17 years (range, 8 to 33).

RESULTS

Survivorship decreased from 84% (95% confidence interval [CI]: 79 to 90) at 5 years to 70% (95% CI: 64 to 77) at 10 years and to 37% (95% CI: 29 to 45) at 20 years. The most common reasons for revision were aseptic loosening (6%) and infection (4%). Risk factors for revision included increasing age at time of surgery (Hazards Ratio [HR] 1.3, P = .01) and use of constrained (HR 1.7, P = .05) or hinged prostheses (HR 4.3, P = .02). There were 86% of patients reporting that their surgery resulted in "a great improvement" or better.

CONCLUSION

Survivorship of TKAs in young patients is less favorable than expected. However, for the patients who responded to our surveys, TKA demonstrated substantial pain relief and improvement in function at 17-year follow-up. Revision risk increased with older age and higher levels of constraint.

Total Knee Arthroplasty in Rheumatoid Arthritis patients with a medial stabilized prosthesis - A retrospective analysis

BACKGROUND

Total Knee Arthroplasty (TKA) has been described as an effective and successful mode of treatment in alleviation of pain and restoration of function in patients with Rheumatoid Arthritis (RA). The array of bone and soft tissue deformities in RA patients can impact initial success and long term durability of TKA. Medial Pivot (MP) prosthesis is fixed bearing asymmetric pivoting design that provides anterior-posterior stability without any post and conserves bone on the femoral side. There are few reports of suitability of experience with MP in RA.

METHODS

Twenty six patients (average age 55 years) with end stage arthritis secondary to RA operated with MP prosthesis were retrospectively followed up. At a minimum follow up of three years, all patients were assessed using Knee Society Score (KSS), Oxford Knee Score (OKS), Pain Catastrophising Scale (PCS) and radiological outcomes.

RESULTS

At final follow-up, patients reported significant improvement in mean KSS-Objective and Functional scores, Oxford Knee Score and Pain Catastrophising Scale (p < 0.05). The mean range of motion achieved at the end of two years ranged from 0 ͦ (extension) to 109.4 ͦ (full flexion). There was no evidence of loosening or osteolysis at minimum follow up of three years.

CONCLUSION

These results endorse satisfactory clinical and radiological outcomes at minimum follow up of three years following Medial Pivot Prosthetic Knee design in RA patients. Further long term follow up is needed to determine the survival analysis of MP design in these patients.

Evaluating Long Term Outcomes and Survivorship of Cruciate Retaining and Sacrificing Knee Replacements Done for Degenerative Arthritis in Patients Under 55 Years

BACKGROUND

Total Knee Arthroplasty (TKA) is the gold standard of treatment for end stage arthritis not responding to conservative treatment. With a recent increase in the younger population presenting with osteoarthritis (OA) we undertook this study to evaluate long-term outcomes and survivorship of TKA in this cohort.

MATERIALS AND METHODS

Our study cohort included 328 patients, < 55 years, with OA, who underwent TKA using Cruciate Retaining (CR), and Posterior Stabilized (PS) implants with a minimum follow up of 15 years. Revision surgery was the end point of our analysis and Kaplan-Meier evaluation of survivorship was measured. Knee Society Scores (KSS) and Range of Motion (ROM) were assessed to evaluate outcomes.

RESULTS

Survivorship of the CR and PS implants with revision as end point, for aseptic loosening was 97.3% and 96%, and revision for all causes was 89.7% and 86.1%, respectively, at 15 years. The outcomes of CR implants were better than the PS cohort in terms of function and survivorship.

CONCLUSION

Long term survivorship and outcome analysis of TKA in patients < 55 years showed good results with excellent survivorship, with both CR and PS implants. The CR cohort demonstrated better long-term survivorship, though the difference was not statistically significant. Deep infection and aseptic loosening were the commonest causes for failure.

Clinical Outcomes and Survivorship of Contemporary Cementless Primary Total Knee Arthroplasties

BACKGROUND

Total knee arthroplasties (TKAs) with cementless fixation have been studied in multiple series with varying success. The aim of this study was to prepare a systematic review of the literature to evaluate clinical outcomes and revtpdelision rates of patients undergoing contemporary cementless TKA.

METHODS

A search of PubMed and MEDLINE was conducted for English-language articles published between 2005 and 2018 to identify studies examining survivorship and clinical outcomes of cementless TKAs. Studies that reported clinical and/or radiographic outcomes were included. Data collected included the number of TKAs, implant utilized, primary diagnosis, mean age and follow-up, implant survivorship, complications, revisions, and clinical outcome scores. All hybrid constructs and revision TKAs were excluded. Poisson regression analysis was used to determine the revision incidence rates per 1,000 person-years.

RESULTS

Forty-three studies with 10,447 TKAs met inclusion criteria, of which 8,187 were primary cementless TKAs. The mean follow-up was 7 years. The revision incidence per 1,000 person-years was 4.8 for all cementless designs. The complication rate for all cementless TKAs was 6%, with deep venous thrombosis being the most common complication. The mean postoperative Knee Society Score and Functional Score were 92 and 83, respectively.

CONCLUSIONS

While newer-generation cementless designs have shown improved survivorship and clinical outcomes compared with earlier-generation cementless designs, the literature for cementless designs remains limited when compared with cemented designs. Further studies are needed to determine if cementless TKA can achieve the same benefits that have been realized with cementless total hip arthroplasty.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Historical and projected fractures associated with mobility scooters presenting to U.S. emergency departments: 2004-2025

Introduction

The proportion of mobility scooter users in the United States continues to rise. However, these devices impart a substantial yet underappreciated risk of serious injury - namely, fractures - on users.

Methods

The purpose of this cross-sectional, retrospective study was to use the National Electronic Injury Surveillance System (NEISS) to quantify the national burden of these device-associated fractures between 2004 and 2017, analyzing in two-year intervals. We also projected estimates to 2025, and described the demographic characteristics of those injured.

Results

We found that national estimates of device-associated fractures increased significantly between the 2004-2005 (N = 2583; C.I. 1851 - 3316) and 2016-2017 (N = 6553; C.I. 5026 - 8081) periods (p < 0.001). A linear regression model (R² = 0.89; P = 0.002) was applied to project 9824 such fractures (C.I. 8273-11,328) in the 2024-2025 period. Injured patients were commonly over age 65 (63.5%; C.I. 57.7%-69.4%) and white (61.4%; C.I. 50.7% - 72.1). Fractures often occurred at home (28.6%; C.I. 22.0%-35.3%) or in public (26.0%; C.I. 21.1%-30.9%).

Conclusion

Our study suggests that osteoarthritic patients relying on mobility scooters to manage pain during ambulation should be considered candidates for total joint replacement procedures. This may help minimize the growing economic and health burden of mobility scooter fractures.

Rates and outcomes of total knee replacement for rheumatoid arthritis compared to osteoarthritis

BACKGROUND

Total knee replacement (TKR) has been shown to perform differently in patients with rheumatoid arthritis (RA) when compared to osteoarthritis (OA). In this study, we compare the survivorship between these two groups and examine patient and prosthesis factors that impact the revision rate.

METHODS

All RA and OA patients undergoing TKR in Australia from 1 September 1999 to 31 December 2016 were included. Revision rates were assessed using Kaplan-Meier estimates of survivorship. The cumulative percent revision analysed age, gender, prosthesis constraint and revision for infection.

RESULTS

There were 541 744 TKR procedures performed including 7542 patients with RA. RA declined as the primary diagnosis from 2.4% of all TKR in 2003 to 0.9% in 2016. Male sex was an independent revision risk in RA patients (hazard ratio (HR) = 1.66, P < 0.001) and OA patients (3.5 years+: HR = 1.09 (1.04-1.15), P < 0.001). Male RA patients had a higher revision rate for infection than females (HR = 3.14, P < 0.001). Females with RA had a lower cumulative percent revision compared to OA females, but males showed no difference between diagnoses. Revision in RA patients was not influenced by age. Compared to OA, RA patients had a decreased revision rate for those aged <65 years, but not for patients aged ≥65 years.

CONCLUSION

The rate of revision after TKR in RA patients is lower than those with OA, but patients with RA are at increased risk of infection, particularly the male group. Prosthesis constraint had no influence on revision rate. Mortality in those undergoing TKR with RA was higher than in those with OA.

Comparable outcomes after total knee arthroplasty in patients under 55 years than in older patients: a matched prospective study with minimum follow-up of 10 years

PURPOSE

To compare outcomes after TKA for osteoarthritis between patients younger than 55 years and older patients.

METHODS

A cohort of 61 patients aged 55 years or younger was prospectively matched for gender, body mass index and knee function with patients with median age of 66 (range 60-70) years. Clinical evaluation was performed by the Knee Society scores (KSS), reduced Western Ontario and McMasters Universities (WOMAC) and Short-Form 12 (SF12) questionnaires. Radiological evaluation was also performed.

RESULTS

The median follow-up was 12 (range 10-14) years. Survival at 14 years was 96.7% (95% CI 92-100%) in the younger group and 98.2% (95% CI 95-100%) in the older group (n.s.). There was no deep infection or loosening of femoral or patellar component in either group. In the younger group, 2 patients required revision (aseptic tibial loosening at 8 years, and polyethylene wear at 10 years). In the older group, there was 1 revision (aseptic tibial loosening). Revision rate was not significantly different (n.s.). Multivariate analysis showed no significant relationship between revision and age, gender or BMI. At 5-year follow-up, there were no significant differences between groups in KSS knee or function, WOMAC pain or function, or SF12 physical or mental, but in the last evaluation there were better results in younger patients for KSS-function (p = 0.018), WOMAC-function (p = 0.028), SF12-physical (p = 0.001) and SF12-mental (p = 0.035), although these differences were not clinically relevant. A significant decline was noted for KSS-function in either group from 5-year to at last follow-up.

CONCLUSIONS

The TKA survival in younger patients was comparable to older active patients, without increased complications or revisions at a minimum follow-up of 10 years. Primary hybrid TKA can provide successful pain relief, function and quality of life in younger patients than 55 years with osteoarthritis. TKA is a suitable option for these young patients with appropriate surgical indications.

LEVEL OF EVIDENCE

II.

Total knee arthroplasty for posttraumatic osteoarthritis in military personnel under age 50

United States military personnel frequently suffer knee injuries. The resulting progressive posttraumatic osteoarthritis (PTOA) causes significant disability in these young high-demand patients for which total knee arthroplasty (TKA) is the only effective treatment of their pain and impairment. Yet the use of this option for treatment of PTOA has not been studied. This retrospective review identified 74 knees in 64 U.S. military personnel who underwent TKA at ≤50 years of age during an 8-year period at a tertiary-care, academic, military medical center. Fifty-five knees (74.3%) experienced one or more prior ligamentous, meniscal, or chondral injuries prior to arthroplasty. Only one subject had a history of osteochondral intra-articular fracture. The average at injury was 29.2 years (95%CI of ±2.50) with an average age at arthroplasty of 44.3 years (±1.11). The most common injury was anterior cruciate ligament rupture (n = 19) with a mean time to TKA of 23.1 (±10.54) and 18.8 years (±7.01) when concomitant meniscal pathology was noted. Nineteen patients were noted to have radiographic and symptomatic end-stage osteoarthritis without a specified etiology at 41.4 years (±1.47) and underwent subsequent TKA. This is the first study to evaluate treatment of end-stage PT OA in young people treated with TKA, finding that the incidence of PTOA as an indication for arthroplasty is significantly higher than among civilians. In this otherwise healthy, high-demand patient population, the rate of OA progression following knee injury is accelerated and the long term implications can be career and life altering. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:677-681, 2017.

Long-term results of total knee arthroplasty in young and active patients with posterior stabilized design

BACKGROUND

The aim of this study was to evaluate long-term quality and performance of cemented posterior-stabilized (PS) total knee arthroplasty (TKA) in young and active patients with gap balancing technique.

METHODS

Between January 2000 and October 2001, 55 TKAs (21 rotating platform [RP] and 34 fixed bearing [FB]) in 41 patients, 60 years and younger, with University of California Los Angeles (UCLA) activity score of five and above were included in this study and prospectively followed. Clinical assessments included Western Ontario and McMaster Universities (WOMAC), Knee Society, UCLA activity score, and Patient Administered Questionnaire (PAQ). Radiographic measurements included component positioning, patellar tilt and thickness, radiolucency, loosening or osteolysis.

RESULTS

At a mean follow-up of 12.3±0.5 years (11 to 13), there was no instability, malalignment, or patellofemoral maltracking. Sixty eight percent of patients were still participating in regular recreational activities at the final follow-up. The mean satisfaction score was 9.1±1.9 and 8.5±2.1 in RP-PS and FB-PS groups, respectively. There was no malalignment or osteolysis, no revision for osteolysis or loosening. One patient in the FB-PS group underwent open reduction and internal fixation for a peri-prosthetic fracture. Overall Kaplan-Meier survivorship was 98%.

CONCLUSION

The PS TKA in young and active patients can provide long-term durability and high quality of function.

LEVEL OF EVIDENCE

III.

Long-term results of cruciate-retaining total knee replacement in patients with rheumatoid arthritis: a minimum 15-year review

BACKGROUND

There is controversy about whether to retain or excise the posterior cruciate ligament in rheumatoid knees because attenuation of the ligament is often present in this subgroup of patients. We reviewed more than 15 years of results of cruciate-retaining total knee replacements (TKRs) in patients with rheumatoid arthritis.

METHODS

We reviewed patients' charts and radiographs to evaluate knee range of motion and flexion contractures, component loosening and osteolysis at the bone-cement interface. Our primary outcome was revision of a femoral or tibial component for any reason, and the secondary outcome was revision for any reason and periprosthetic fracture during the follow-up period.

RESULTS

Our study included 112 patients (7 men, 105 women, 176 knees). Their mean age was 49.3 (range 33-64) years. Twenty-one patients died and 16 were lost to follow-up, leaving 75 patients (119 knees) with a minimum follow-up of 15 (mean 16.1) years for our analysis. Of these, 61 patients (101 knees) were available for clinical and radiological evaluation at the final follow-up assessment. At a mean of 12.2 (range 6-16) years, revision was necessary in 14 patients (19 knees), including 1 patient with an infection. Eleven patients (11 knees) had periprosthetic fractures at a mean of 11.4 (range 5-14) years after the index operation. The survival rate, with the end point being revision of the femoral or tibial component for any reason, was 98.7% at 10 years and 83.6% at 17 years. The survival rate of revision and periprosthetic fracture was 97.6% at 10 years and 76.9% at 17 years.

CONCLUSION

Special attention should be paid to component loosening or periprosthetic fracture after more than 10 years of follow-up in this subgroup of patients.

Future patient demand for shoulder arthroplasty by younger patients: national projections

BACKGROUND

The outcomes of shoulder arthroplasties in younger patients (55 years or younger) are not as reliable compared with those of the general population. Greater risk of revision and higher complication rates in younger patients present direct costs to the healthcare system and indirect costs to the patient in terms of quality of life. Previous studies have suggested an increased demand for shoulder arthroplasties overall, but to our knowledge, the demand in younger patients has not been explored.

QUESTIONS/PURPOSES

We asked: (1) What was the demand for shoulder arthroplasties between 2002 and 2011 in the United States for all patients and a specific subpopulation of patients who were 55 years old or younger? (2) How is the demand for shoulder arthroplasties in younger patients projected to change through 2030? (3) How is procedural demand projected to change in younger patients through 2030, and specifically, what can we anticipate in terms of hemiarthroplasty volume compared with that of total shoulder arthroplasty?

METHODS

We used the National Inpatient Sample database to identify primary shoulder arthroplasties performed between 2002 and 2011. A Poisson regression model was developed using the National Inpatient Sample data and United States Census Bureau projections on future population changes to predict estimated national demand for total shoulder arthroplasties and hemiarthroplasties in all patients and in the subpopulation 55 years old or younger. This model was projected until 2030, with associated 95% CIs. We then specifically analyzed the projected demand of hemiarthroplasties and compared this with demand for all arthroplasty procedures in the younger patient population.

RESULTS

Demand for shoulder arthroplasties in patients 55 years or younger is increasing at a rate of 8.2% per year (95% CI, 7.06%-9.35%), compared with a growth rate of 12.1% (95% CI, 8.35%-16.02%) per year for patients older than 55 years. In 2002, 15.9% (3587 of 22,617 captured in the National Inpatient Sample) of primary shoulder arthroplasties were performed in patients 55 years old or younger. In 2011, the relative size of the younger patient population had decreased to 11.0% (7001 of 63,784) of all recipients of shoulder arthroplasties. The demand for primary shoulder arthroplasties among younger patients is projected to increase by 333.3% (95% CI, 257.0%-432.5%) from 2011 to 2030. However, in patients older than 55 years demand is projected to increase by 755.4% (95% CI, 380.7%-1511.1%). Therefore, despite the increased predicted demand for shoulder arthroplasties in younger patients, they are predicted to account for only 4% of all recipients by 2030. The rate of hemiarthroplasties in patients 55 years or younger showed a 16.5% decline per year (95% CI, 16.1%-17.1%) from 2002 (53.6% of all arthroplasties) to 2011 (34.2% of all arthroplasties). By 2030, hemiarthroplasties are projected to account for only 23.5% of all shoulder arthroplasties in patients 55 years or younger.

CONCLUSIONS

The demand for shoulder arthroplasties in younger patients continues to increase in the United States; however, rates of hemiarthroplasties are declining. The demand has substantial implications for future revision arthroplasties, which include the direct healthcare costs of revision arthroplasty, the indirect societal burden of missed productivity owing to time away from work, and the increased burden of the need for qualified surgeons to meet the demand. Despite the increasing rate of arthroplasties performed in younger patients, current and projected demands remain greater for older patients, indicating a disproportionately greater need for shoulder arthroplasties in older patients. This is in contrast to the trends observed in the literature regarding hip and knee arthroplasties that show projected demands to be greater in younger patients. Factors responsible for the difference in demand require further investigation but may be related to changing indications, reported poorer outcomes in younger patients, the increased popularity of reverse shoulder arthroplasties in the elderly, or the evolution of nonarthroplasty options.

LEVEL OF EVIDENCE

Level III, prognostic study.

Lower function, quality of life, and survival rate after total knee arthroplasty for posttraumatic arthritis than for primary arthritis

BACKGROUND AND PURPOSE

Total knee arthroplasty (TKA) for treatment of end-stage posttraumatic arthritis (PTA) has specific technical difficulties and complications. We compared clinical outcome, postoperative quality of life (QOL), and survivorship after TKA done for PTA with those after TKA performed for primary arthritis (PA).

PATIENTS AND METHODS

We retrospectively reviewed patients who were operated on at our institution for PTA between 1998 and 2005 (33 knees), and compared them to a matched group of patients who were operated on for PA during the same period (407 knees). Clinical outcomes and postoperative QOL were compared in the 2 groups using Knee Society score (KSS), range of motion (ROM) of the knee, and the knee osteoarthritis outcomes score (KOOS). Implant survival rate was calculated using Kaplan-Meier analysis.

RESULTS

At a mean follow-up of 11 (5-15) years, KSS knee increased from mean 39 (SD 18) to 87 (SD 16) in the PA group (p = 0.003), and from 31 (SD 11) to 77 (SD 15) in the PTA group (p = 0.003). KSS function increased from 55 (12) to 89 (25) in the PA group (p = 0.008) and from 44 (SD 14) to 81 (SD 10) in the PTA group (p = 0.008). Postoperative ROM also improved in both groups, from 83° to 108° in the PTA group (p < 0.001) as opposed to 116° to 127° in the PA group (p = 0.001), with lower results in the PTA group (p < 0.001). KOOS was lower in the PTA group (p < 0.001). The survival rate of TKA at 10 years with an endpoint defined as "any surgery on the operated knee" showed better results in the PA group (99%, CI: 98-100 vs. 79%, CI: 69-89; p < 0.001).

INTERPRETATION

Patients and surgeons should be aware that clinical outcome and implant survival after TKA for PTA are lower than after TKA done for PA.

Osteoarthritis in young, active, and athletic individuals

Osteoarthritis (OA) is one of the most devastating chronic conditions that affect people around the world. Although the usual population associated with the condition is the elderly, who are mostly inactive, athletes and younger individuals are also susceptible. Depending on the population, the etiology may differ; injuries, occupational activities, and obesity appear to be the most common causes of OA in young and athletic populations. Diagnosing OA in athletes and young individuals is sometimes challenging because of their increased pain tolerance. However, the treatment of OA in these populations does not differ from its management in the general population. Several considerations need to be taken into account when choosing a treatment modality. The purpose of this review is to address OA in athletes and younger individuals and to discuss its presentation, diagnosis, and treatment.

Arthroplasty in young adults: options, techniques, trends, and results

Total knee arthroplasty (TKA) has been established as a very successful and commonly performed procedure for primary and secondary osteoarthritis, and also for inflammatory arthropathies of the knee in all age groups and both genders. It has predominantly been used as a procedure in the age group of patients 65 years and above. Consequently, the literature is replete with data relevant to various issues associated with TKA in the above 65 years age group population. Although there is reasonable clarity and consensus on the broad parameters of the use of TKA in the above 65 years age group (older), this cannot be said for the same issue as relevant to the below 65 years age group (young adults). Over the last 2 decades there has been an increasing tendency toward the use of TKA in young adults, with some countries reporting a 5-fold increase in the last 10 years [1]. The present article is designed to review the most recent literature specific to this subject and assess it vis-à-vis various issues as listed in the subsequent text, with the aim of highlighting evolving thoughts and trends, which could be useful for decision making by clinicians practicing in the community.

Revision total knee arthroplasty in the young patient: is there trouble on the horizon?

BACKGROUND

The volume of total knee arthroplasties, including revisions, in young patients is expected to rise. The objective of this study was to compare the reasons for revision and re-revision total knee arthroplasties between younger and older patients, to determine the survivorship of revision total knee arthroplasties, and to identify risk factors associated with failure of revision in patients fifty years of age or younger.

METHODS

Perioperative data were collected for all total knee arthroplasty revisions performed from August 1999 to December 2009. A cohort of eighty-four patients who were fifty years of age or younger and a cohort of eighty-four patients who were sixty to seventy years of age were matched for the date of surgery, sex, and body mass index (BMI). The etiology of failure of the index total knee arthroplasty and all subsequent revision total knee arthroplasties was determined. Kaplan-Meier survival curves were used to evaluate the timing of the primary failure and the survivorship of revision knee procedures. Finally, multivariate Cox regression was used to calculate risk ratios for the influence of age, sex, BMI, and the reason for the initial revision on survival of the revision total knee arthroplasty.

RESULTS

The most common reason for the initial revision was aseptic loosening (27%; 95% confidence interval [CI] = 19% to 38%) in the younger cohort and infection (30%; 95% CI = 21% to 40%) in the older cohort. Of the twenty-five second revisions in younger patients, 32% (95% CI = 17% to 52%) were for infection, whereas 50% (95% CI = 32% to 68%) of the twenty-six second revisions in the older cohort were for infection. Cumulative six-year survival rates were 71.0% (95% CI = 60.7% to 83.0%) and 66.1% (95% CI = 54.5% to 80.2%) for revisions in the younger and older cohorts, respectively. Infection and a BMI of ≥ 40 kg/m(2) posed the greatest risk of failure of revision procedures, with risk ratios of 2.731 (p = 0.006) and 2.934 (p = 0.009), respectively.

CONCLUSIONS

The survivorship of knee revisions in younger patients is a cause of concern, and the higher rates of aseptic failure in these patients may be related to unique demands that they place on the reconstruction. Improvement in implant fixation and treatment of infection when these patients undergo revision total knee arthroplasty is needed.

Are younger patients undergoing TKAs appropriately characterized as active?

BACKGROUND

The use of TKAs in young patients is increasing. Demographic characteristics and activity levels among this patient group may affect implant selection, performance, and survivorship. Patient age (≤ 55 years) and preoperative diagnosis have been used to define this patient group, with the presumption that these patients are more active than older patients with similar indications for TKA.

QUESTIONS/PURPOSES

We questioned whether (1) demographic features of young patients support high activity expectations after TKA, and (2) preoperative or postoperative functional activity measures support projections that young patients are active after TKA.

METHODS

We retrospectively compared demographic characteristics (gender, BMI, diagnosis) and functional activity profile (as determined by preoperative and postoperative UCLA activity score and functional subscores of The Knee Society and WOMAC instruments) for 150 patients 55 years old or younger (181 TKAs) and 262 patients who were between 65 to 75 years old (314 TKAs) at the time of surgery.

RESULTS

Younger patients having TKAs were significantly more likely than older patients to be female (74% versus 60%, p < 0.001) and to have diagnoses other than osteoarthritis (18% versus 3%, p < 0.001). BMI was significantly greater among younger female patients than among other age and gender combinations (35 kg/m(2) versus 31 kg/m(2), p < 0.001). Male patients had higher mean postoperative UCLA activity scores (5.5 versus 4.4, p < 0.001), Knee Society function subscores (80.2 versus 66.4, p < 0.001), and WOMAC function subscores (82.8 versus 74.2, p < 0.01) compared with female patients, but these were not different in older versus younger patients.

CONCLUSIONS

Sustained high activity levels are not likely to be a principal cause of revision TKAs among younger patients when considering age and diagnosis alone. Determining the effect of activity on survivorship of prosthetic designs and techniques should be based on measured functional activity instead of using age and diagnosis as surrogates for activity.

LEVEL OF EVIDENCE

Level III, therapeutic study. See the Instructions for Authors for a complete description of levels of evidence.

Total knee arthroplasty in patients with juvenile idiopathic arthritis

BACKGROUND

Total knee arthroplasty (TKA) for juvenile idiopathic arthritis is rare but is nonetheless indicated for many patients with this disease. Few reports exist on the results of TKA in patients with juvenile idiopathic arthritis.

QUESTIONS/PURPOSES

It was sought to determine (1) survivorship and (2) functional outcomes of TKAs in patients with juvenile idiopathic arthritis.

METHODS

Results were combined from patients treated by experienced surgeons at five hospitals between 1979 and 2011. Two hundred nineteen patients (349 TKAs) were identified and contacted to survey their outcomes at a minimum followup of 2 years (mean, 12 ± 8 years; range, 2-33 years). The average age at surgery was 28.9 ± 9.7 years (range, 11-58 years). Data on revision surgery and ability to perform daily activities were collected.

RESULTS

The 10-year survivorship was 95%, decreasing to 82% by 20 years. At latest followup, 31 of 349 TKAs (8.9%) had been revised for either polyethylene failure or loosening (18 TKAs), infection (four), stiffness (three), periprosthetic fractures (two), bilateral amputation for vascular reasons (two), patellar resurfacing (one), and instability (one). Walking tolerance was unlimited in 49%, five to 10 blocks in 23%, and less than five blocks in 28%. Eleven percent could not manage stairs, and another 59% depended on railings. A cane was used by 12% and crutches by 7%; 12% were wheelchair-dependent.

CONCLUSIONS

TKA survivorship in patients with juvenile idiopathic arthritis was inferior to that typically seen in younger patients with osteoarthritis or even rheumatoid arthritis confirming results of earlier studies with smaller patient numbers. This is especially disconcerting because younger patients require better durability of their TKAs.

Anthropometric measurements of the human distal femur: a study of the adult Malay population

The distal femurs of 100 subjects (50 men, 50 women) from the Malay population aged between 19 and 38 years were scanned to measure the anterior-posterior (AP) and medial-lateral (ML) width. The mean AP values were 64.02 ± 3.38 mm and 57.33 ± 3.26 mm for men and women, respectively, and the mean ML values were 74.91 ± 3.52 mm and 64.53 ± 3.07 mm. We compared our data to that published previously for the Chinese and Indian populations. It was found that the Malay population had smaller distal femur than that of the Chinese but was larger than that of the Indian population (P < 0.05). In conclusion, although it is well established that Asians have a smaller distal femur size than that of the Western population, the variations in different Asian ethnicities may need to be considered when designing the appropriate knee implant.

Relationship between patient-based outcome score and conventional objective outcome scales in post-operative total knee arthroplasty patients

PURPOSE

Evaluations for knee osteoarthritis (OA) or post-operative total knee arthroplasty (TKA) have mainly been assessed by objective scales. Though the Knee injury and Osteoarthritis Outcome Score (KOOS) is attracting attention as a patient-based outcome score, the relationship with conventional objective scales after TKA remains controversial. The purpose of this study was to investigate the relationship between KOOS and conventional objective scales and evaluate the features of patient-based outcome scores.

METHODS

Subjects were 130 post-operative patients involving 186 knees treated with TKA. Their mean age was 74.0 ± 8.0 years, and the follow-up period was 43 months. Japanese Orthopaedic Association (JOA) score, original Knee Society Score (KSS) and surgeon's satisfaction score were scored as conventional objective scales besides KOOS. Spearman's correlation coefficient was estimated between these scales. Comparisons between OA and rheumatoid arthritis (RA) as well as primary and revision surgery were performed by the Mann-Whitney U test.

RESULTS

There were strong correlations between KOOS activities of daily living (ADL) and JOA score (r = 0.806), KSS function score (r = 0.803) and between KOOS pain and KSS knee score (r = 0.689). However, there was a poor correlation between KOOS and surgeon's satisfaction score (r = 0.188-0.321). TKA for RA showed poorer results only in KOOS pain (p = 0.003), and revision surgery showed poorer results in KSS function, KOOS symptoms and KOOS quality of life (QOL).

CONCLUSIONS

This study suggested that conventional objective scales reflected mainly ADL disturbances in post-operative TKA patients. Furthermore, patient-based outcome scores made it possible to evaluate and detect a minute change of knee pain and QOL in TKA patients. The Japanese KOOS was a useful tool to evaluate conditions after TKA.

Ten-year survival of cemented total knee replacement in patients aged less than 55 years

We report the ten-year survival of a cemented total knee replacement (TKR) in patients aged < 55 years at the time of surgery, and compare the functional outcome with that of patients aged > 55 years. The data were collected prospectively and analysed using Kaplan-Meier survival statistics, with revision for any reason, or death, as the endpoint. A total of 203 patients aged < 55 years were identified. Four had moved out of the area and were excluded, leaving a total of 221 TKRs in 199 patients for analysis (101 men and 98 women, mean age 50.6 years (28 to 55)); 171 patients had osteoarthritis and 28 had inflammatory arthritis. Four patients required revision and four died. The ten-year survival using revision as the endpoint was 98.2% (95% confidence interval 94.6 to 99.4). Based on the Oxford knee scores at five and ten years, the rate of dissatisfaction was 18% and 21%, respectively. This was no worse in the patients aged < 55 years than in patients aged > 55 years. These results demonstrate that the cemented PFC Sigma knee has an excellent survival rate in patients aged < 55 ten years post-operatively, with clinical outcomes similar to those of an older group. We conclude that TKR should not be withheld from patients on the basis of age.

Total Knee Arthroplasty in Rheumatoid Arthritis

The course of rheumatoid arthritis varies from mild disease to severe joint destructive variant that progresses rapidly, eventually leading to unremitting pain and joint deformity. In advanced disease, total knee arthroplasty has proven to be the most successful intervention that reduces knee pain and improves physical function in rheumatoid arthritis patients. However, as rheumatoid arthritis patients carry additional potential for late complications, many important considerations regarding preoperative evaluation and surgical technique must be taken into account in order to improve the results of total knee arthroplasty in this subgroup of patients.

A Comparison of Patella Retention versus Resurfacing for Moderate or Severe Patellar Articular Defects in Total Knee Arthroplasty: Minimum 5-year Follow-up Results

Purpose

The purpose of this study is to assess the clinical and radiological results of patients who underwent patellar retention or resurfacing for moderate or severe patellar articular defects during total knee arthroplasty and evaluate the clinical efficacy of patellar resurfacing according to the articular defect of the patella.

Materials and Methods

From May 2003 to March 2006, 252 patients (277 cases) underwent total knee arthroplasty by one surgeon. Intraoperatively, we divided these patients into a moderate articular defect group (50-75%: group I) and a severe articular defect group (75-100%: group II) and randomly performed patellar resurfacing. The average age was 67.2 years. There were 234 female and 17 male patients. The average follow-up period was 74.6 months. Clinical outcomes were analyzed using the Knee Society (KS) knee score. Functional score, Hospital for Special Surgery (HSS) score, Feller patellar score and range of motion (ROM). Radiological outcomes were analyzed using the congruence angle, Insall-Salvati ratio and patella tilt angle.

Results

The KS knee score and functional score at the last follow-up were 84.4/73.1 in the retention group and 85.2/71.8 in the resurfacing group (p=0.80, p=0.63) in group I. In group II, the values were 82.1/75.1 and 87.0/71.2, respectively (p=0.51, p=0.26). The HSS score and Feller patella score were 86.7/20.3 in the retention group and 84.3/21.7 in the resurfacing group (p=0.31, p=0.29) in group I. In group II, the values were 91.6/21.2 and 85.5/22.1, respectively (p=0.37/p=0.30). The knee ROM (p=0.36/p=0.41), congruence angle (p=0.22/p=0.16), Insall-Salvati ratio (p=0.16/p=0.21) and patella tilt angle (p=0.12/p=0.19) were not statistically different between the two groups.

Conclusions

In this study, we could not find any correlations between the degree of patellar articular defect and patellar resurfacing in terms of the clinical and radiological results. Therefore, patellar articular defects is thought to be less meaningful in determining patellar resurfacing.

Update in surgery for osteoarthritis of the knee

Osteoarthritis is a leading cause of disability with incidence and prevalence rising in most nations. Management to address the degenerative joint is stratified according to degree of severity of involvement and always begins with non-surgical modalities before progressing through a range of surgeries, including arthroscopy, osteotomy, unicompartmental and total knee replacement. Predictability of results depends on the type of procedure with total joint replacement giving the most sustainable relief from symptoms, improvement of function and longevity of construct. Obesity is a health priority in developed countries where it is overrepresented in patients presenting for joint replacement. Complications, poor patient satisfaction and joint function can be directly attributable to obesity. Efforts to address obesity should be considered as part of the approach to managing osteoarthritis.

Average 10.1-year follow-up of cementless total knee arthroplasty in patients with rheumatoid arthritis

BACKGROUND

Total knee arthroplasty (TKA) using a cemented technique has been recommended in patients with rheumatoid arthritis owing to the initial stability of the fixation and long-term durability of the components; however, similar long-term follow-up results have been reported in patients who have undergone cementless TKA. The purpose of this study was to evaluate the radiologic and clinical outcomes of cementless TKA in patients with rheumatoid arthritis.

METHODS

We enrolled patients undergoing cementless TKA from March 1990 to February 2000. Clinical and radiologic evaluations were performed using the Knee Society clinical rating system and radiographic evaluation and scoring system.

RESULTS

We included the cases of 112 patients who underwent 179 cementless TKA procedures in our analysis. Their mean age was 62.3 years, and the mean follow-up period was 10.1 years. The final survival rate was 0.968 at the 15.5-year follow-up. Regarding radiologic results after surgery, the mean total valgus angle was 6.7°, the mean femoral flexion angle was 97.5° and the mean tibial angle was 89.2° on the anteroposterior radiographs. On the lateral films, the mean femoral flexion angle was 1.6° and the mean tibial angle was 89.2°. At the last follow-up, the mean total valgus angle was 6.5°, the mean femoral flexion angle was 97.4° and the mean tibial angle was 89.1°, as seen on the anteroposterior view. On the lateral views, the mean femoral flexion angle was 1.4° and the mean tibial angle was 89.0°. Regarding the clinical outcome, the mean knee score and function score on the Knee Society clinical rating system were also enhanced from 47.5 and 43.6, respectively, before the operation to 91.2 and 82.3, respectively, at the last follow-up.

CONCLUSION

On radiologic and clinical follow-up of cementless TKA for patients with rheumatoid arthritis, there were no serious complications, and the results of the operation were satisfactory with improvement in range of motion and clinical symptoms.

What is the evidence for total knee arthroplasty in young patients?: a systematic review of the literature

BACKGROUND

TKA is commonly performed to treat advanced inflammatory and degenerative knee arthritis. With increasing use in younger patients, it is important to define the best practices to enhance clinical performance and implant longevity.

QUESTIONS/PURPOSES

We systematically reviewed the literature to assess: (1) how TKAs perform in young patients; (2) whether the TKA is a durable procedure for young patients, and (3) what guidance the literature outlines for TKA in young patients.

METHODS

We searched the literature between 1950 and 2009 for all studies reporting on TKAs for patients younger than 55 years that documented clinical and radiographic assessments with a minimum 2-year followup. Thirteen studies, reporting on 908 TKAs performed for 671 patients, met these criteria.

RESULTS

Mean Knee Society clinical and functional scores increased by 47 and 37 points, respectively. Implant survivorship was reported between 90.6% and 99% during the first decade and between 85% and 96.5% during the second decade of followup. The literature does not direct specific techniques for TKA for young patients.

CONCLUSIONS

TKA provides surgeon-measured clinical and functional improvements with a moderate increase in second-decade implant failures. Improvements in study design and reporting will be beneficial to guide decisions regarding implant selection and surgical technique.

LEVEL OF EVIDENCE

Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Total knee arthroplasty in younger patients: a 13-year follow-up study

Total knee arthroplasty (TKA) is a well-established treatment at the end stage of a degenerated knee joint. This operative treatment generally relieves pain, improves physical function, and has a high level of patient satisfaction, especially in the elderly. Younger patients, however, are demanding and have a higher level of physical activity compared to elderly patients. One could therefore expect more mechanical problems such as prosthetic loosening and polyethylene wear after long-term follow-up. The goal of this retrospective cohort study was to determine the survival and long-term results of TKA in young patients. Patients who received a TKA at age 60 years or younger for any reason were included. Minimum follow-up was 10 years. Thirty-nine TKAs (Anatomic Graduate Components; Biomet, Warsaw, Indiana) in 31 patients were included. Average patient age was 52.6 years. There were 3 revisions because of infection; in 1 knee the patella was revised because of aseptic loosening. After an average 13-year follow-up, the survival rate was 89.7% and function scores showed a reasonably functioning TKA. There was no difference in survival rate and function scores between patients with rheumatoid arthritis and those with primary or secondary (posttraumatic) osteoarthritis. Our experience with TKA in a younger patient population has been encouraging. The risk of loosening and wear of the implant in our study is low, and this type of TKA also seems to be an effective and safe treatment for younger patients.

Management of osteoarthritis of the knee in the active patient

Total knee arthroplasty has been extremely successful in elderly patients with osteoarthritis. However, there is considerable controversy regarding how best to treat the younger, athletic patient with advanced arthritis. Treatment options range from nonsurgical management with exercise and nonsteroidal anti-inflammatory drugs, to joint arthroplasty with activity modification. When properly indicated, arthroscopic débridement, high tibial osteotomy, unicondylar knee arthroplasty, and total knee arthroplasty allow younger patients with arthritis to maintain an active, healthy lifestyle.

Knee arthroplasty in the young patient: survival in a community registry

Operative options for the younger patient with an arthritic knee remain controversial. We prospectively followed 1047 patients 55 years old or younger who underwent knee arthroplasty in a community joint registry over a 14-year period. Patients were implanted with 1047 joints of three predominant designs by 48 surgeons in four hospitals associated with a community joint registry. The mean age for this cohort was 49.8 years, and 62.8% (657/1047) of the patients were female. There were a total of 73 revisions performed, 5.6% (37/653) in women and 9.2% (36/394) in men. Cemented TKAs performed best, with a cumulative revision rate of 15.5%, compared to 32.3% in unicompartmental knee arthroplasty (UKA) patients and 34.1% in cementless designs. Men had a higher cumulative revision rate than women, 31.9% compared to 20.6%. Adjusting for implant type and gender, there was no difference in cumulative revision rate based on diagnosis (OA versus other) or age group (< or = 40, 41-45, 46-50, 51-55 years) or between cruciate-retaining and -substituting designs. Eighty five percent of cemented TKA implants survived at 14 years in the population under 55 years of age in this community registry. Cementless designs and UKA increased revision risk independently.

LEVEL OF EVIDENCE

Level II, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Total knee arthroplasty for isolated patellofemoral arthritis in younger patients

Are the results of total knee arthroplasty for isolated patellofemoral osteoarthritis (OA) in younger patients as good as with patellofemoral arthroplasty? We retrospectively compared the outcomes of 33 TKAs in 27 patients with patellofemoral OA younger than 60 years of age (average, 52 years) to those for a matched group of patients with primarily tibiofemoral arthritis. A cemented posterior cruciate ligament-retaining prosthesis was used in 26 of the 27 knees. We recorded the intraoperative condition of the cartilage. Patients were followed a minimum of 2 years (average, 6.2 years). Average Knee Society knee scores improved from 49 preoperatively to 88 at final followup. Average pain scores from 5 to 44 with 29 knees rated with minimal or no pain; two patients reported anterior knee pain. There were no infections, revisions, reoperations, manipulations, patellar instabilities, patellar fractures, or component loosenings. The results in these patients were as good as those for younger historical control patients undergoing patellofemoral arthroplasty and the complication rates lower. The data were similar to those for our matched group of patients with primarily tibiofemoral OA. We believe our data should raise doubts about the use of patellofemoral arthroplasty in any patient.

LEVEL OF EVIDENCE

Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

[Results for endoprosthetic care in patients younger than 50 years]

Arthroplasty has become the most successful surgical procedure in developed countries. Replacement of severely damaged joints results in a substantial relief of pain, as the main symptom of osteoarthritis, in the majority of treated patients. With improved results in endoprosthetic surgery over the last decades, however, patients are increasingly undergoing the procedure to enhance their functional capacity and physical mobility. Especially younger patients, who cannot accept a restriction in their professional or sports activity, have become demanding candidates for surgery. This review summarizes the published results on shoulder, hip, knee, ankle and first metatarsophalangeal joint replacement in patients who are younger than 50 years of age. Mid- and long-term follow-up studies in this age group are evaluated in terms of prosthesis survival as well as functional improvement.

Cemented total knee arthroplasty using a modern prosthesis in young patients with osteoarthritis

Fifty-two consecutive cemented total knee arthroplasties were performed using the Press-Fit Condylar (DePuy, Warsaw, Ind) knee system on patients aged 55 years or younger at Mayo Clinic Rochester from 1988 to 1994. Patients were followed for a minimum of 10 years, with an average follow-up of 12 years (range, 10-15 years). There were 8 total revisions (15%), including 2 revisions before 10 years, one for sepsis at 1 year, and one for instability at 8 years. Six revisions occurred between 10 and 15 years, all associated with polyethylene wear and osteolysis. Implant survival rate was estimated to be 96% at 10 years and 85% at 15 years of follow-up.

Total knee arthroplasty in young active patients using a highly congruent fully mobile prosthesis

A consecutive cohort of 63 young patients (80 knees; mean age, 50.7 years) received a Rotaglide mobile knee (Corin Ltd, Cirencester, UK) prosthesis as a primary procedure by a single UK surgeon. Mean follow-up period is 7.3 years (range, 3-12 years). Patients were assessed using the International Knee Society Score and the Oxford Knee Score. Radiolucency was assessed using the Knee Society roentgenographic system. The patients demonstrated an excellent knee and function International Knee Society Score of 98 and 93.6, respectively, with an Oxford Knee Score of 15.5. One knee was revised for traumatic dislocation of the mobile bearing. There were no revisions for aseptic loosening or deep infection. This study demonstrates encouraging midterm results for this device in a young patient cohort.

Total knee arthroplasty effectiveness in patients 55 years old and younger: osteoarthritis vs. rheumatoid arthritis

In the past, total knee arthroplasty, although very successful, was only indicated for an elderly population. Recently though, several papers have been published confirming that total knee arthroplasty is effective in younger patients. This paper supports the results of those papers. In our study, 207 total knee arthroplasties were performed on patients 55 years old and younger using a posterior cruciate-retaining prosthesis. There was an overall survival rate of 97.6% with an average follow-up of 9.1 years. There were some minor variations in the outcome of the operation based on diagnosis (osteoarthritis vs. rheumatoid arthritis). The success also continued over time with an estimated survival rate of 94.8% at 12 years. Total knee arthroplasty is an effective operation in patients younger then 55 years old.

Ankle arthropathy of hemochromatosis: a case series and review of the literature

BACKGROUND

Genetic hemochromatosis is a relatively common disease that may present as an arthropathy. In particular, arthropathy of the ankle is invariably bilateral and occurs in young men. However, the orthopaedic management of this condition has been poorly documented.

METHODS

Four patients with hemochromatic ankle arthropathy were treated with unilateral mobile bearing total ankle arthroplasty.

RESULTS

All four patients had good relief of symptoms after arthroplasty.

CONCLUSIONS

Hemochromatosis should be considered when symmetrical ankle arthropathy occurs in a young man. Early diagnosis is necessary to prevent extra-articular progression of the disease and inappropriate management.

Five- to 12-year follow-up of a hydroxyapatite-coated, cementless total knee replacement in young, active patients

We carried out a prospective study of 118 hydroxyapatite-coated, cementless total knee replacements in patients who were ≤ 55 years of age and who had primary (92; 78%) or post-traumatic (26; 22%) osteoarthritis. The mean period of follow-up was 7.9 years (5 to 12.5). The Knee Society clinical scores improved from a pre-operative mean of 98 (0 to 137) to a mean of 185 (135 to 200) at five years, and 173 (137 to 200) at ten years. There were two revisions of the tibial component because of aseptic loosening, and one case of polyethylene wear requiring further surgery. There was no osteolysis or progressive radiological loosening of any other component. At 12 years, the overall rate of implant survival was 97.5% (excluding exchange of spacer) and 92.1% (including exchange of spacer).

Cementless total knee replacement can achieve excellent long-term results in young, active patients with osteoarthritis. In contrast to total hip replacement, polyethylene wear, osteolysis and loosening of the prosthesis were not major problems for these patients, although it is possible that this observation could change with longer periods of follow-up.

[Cartilage cell transplantation as an alternative to endoprosthesis]

The incidence of cartilage lesions is high. Due to pain and loss of function, long-term therapy is often necessary. Isolated, full-thickness articular cartilage lesions with a diameter of 4 cm2 are indications for chondrocyte transplantation. Many outcome studies report good long-term results. In recent years, the cultivation of chondrocytes has changed. Histologic investigations show hyalin-like cartilage after transplantation. Large cartilage lesions facing each other are a therapeutic dilemma in young patients. Implanting unicondylar or bicondylar prostheses is sometimes the last resort for these patients, and there are several reports of good clinical outcome. Cartilage transplantation has until now been recommended for patients younger than 50. It is not an alternative to joint replacement.

Revision total knee arthroplasty with the Total Condylar III system in inflammatory arthritis

We report a consecutive series of 16 revision total knee arthroplasties using the Total Condylar III system in 14 patients with inflammatory arthritis which were performed between 1994 and 2000. There were 11 women and three men with a mean age of 59 years (36 to 78). The patients were followed up for 74 months (44 to 122). The mean pre-operative Knee Society score of 37 points (0 to 77) improved to 88 (61 to 100) at follow-up (t-test, p < 0.001) indicating very good overall results. The mean range of flexion improved from 62 degrees (0 degrees to 120 degrees) to 98 degrees (0 degrees to 145 degrees) (t-test, p < 0.05) allowing the patients to stand from a sitting position. The mean Knee Society pain score improved from 22 (10 to 45) to 44 (20 to 50) (t-test, p < 0.05). No knee had definite loosening, although five showed asymptomatic radiolucent lines. Complications were seen in three cases, comprising patellar pain, patellar fracture and infection. These results suggest that the Total Condylar III system can be used successfully in revision total knee arthroplasty in inflammatory arthritis.

Long-term results of total knee arthroplasty in young patients with rheumatoid arthritis

Forty-seven cemented total knee arthroplasties in 32 patients with rheumatoid arthritis who were 55 years or younger (average, 43) were followed until death or a minimum of 15 years. The average follow-up was 18 years. There were 6 revisions; 5 of 6 revisions had severe polyethylene wear and osteolysis. All revisions occurred after 17 years (range, 17-23). Three of these had fracture of the tibial component associated with polyethylene wear through; the remaining 2 had loose tibial and femoral components. One patient sustained a distal femoral periprosthetic fracture requiring revision of the total knee. Cemented total knee arthroplasty in the young patient with rheumatoid arthritis is reliable and durable at an average 18 years of follow-up with an estimated survivorship of 100% at 15 years and 93.7% at 20 years.

Total knee replacement in juvenile rheumatoid arthritis

In general, longer operative times and in some cases increased blood requirements can be expected with TKA in patients with juvenile rheumatoid arthritis. Complications also are more frequent. Pain relief is usually good to excellent, and function and deformity are significantly improved. Range of motion after TKA for juvenile rheumatoid arthritis is usually less than that obtained in osteoarthritis, but still allows for dramatic improvements in performing activities of daily living (Figure 3).

Long-term followup of posterior-cruciate-retaining TKR in patients with rheumatoid arthritis

A consecutive series of 220 primary posterior-cruciate ligament-retaining total knee replacements were done in 148 patients with rheumatoid arthritis. From this group, 212 total knee replacements (141 patients) were followed up for an average of 10 years. Average knee scores at 5, 10, 15, and 20 years after operation improved to 86, 83, 88, and 89, respectively, and average function scores improved to 70, 72, 64, and 88, respectively. Five knees (2.4%) were revised for deep infection. Posterior instability, recurvaum, or mediolateral instability, combined or otherwise, occurred in 15% (32 knees; in 31 patients). Three tibial components (1.4%) were revised: one for suspected aseptic loosening and two for instability. Excluding infections and failed metal-backed patellas, Kaplan-Meier survival rates were 99.5%, 97.9%, and 96.5%, respectively. Favorable long-term results may be achieved with posterior-cruciate ligament-retaining total knee replacements in patients with rheumatoid arthritis. Concern remains, however, about rotational instability in certain cases associated with preoperative genu-valgum and ipsilateral planovalgus deformity.

Patellar resurfacing reduces pain after TKA for juvenile rheumatoid arthritis

Influence of patellar resurfacing after knee replacement and the frequency of patella infera and its relation to the postoperative appearance of the knee pain were assessed in patients with juvenile rheumatoid arthritis. Seventy-seven total knee arthroplasties using the AGC prosthesis with nonconstrained components were done on 52 patients with a mean followup of 7.3 years (range, 3-13 years). Anterior knee pain was present in 14 of 30 patients (47%) with an unreplaced patella and in two of 18 patients (11%) with patella resurfacing. The patella was replaced in 18 patients (35%) and in 23 of 77 knees (30%). Neither revision surgery of implanted patellar components nor any later resurfacing of an unreplaced patella were done during the followup. Preoperatively using the Insall-Salvati ratio, the majority of knees (54 of 77) had a low-riding patella. Patella infera occurred commonly in patients with juvenile rheumatoid arthritis. No connection between patella infera and anterior knee pain was found.

Posterior cruciate ligament-substituting total knee arthroplasty in young rheumatoid patients with advanced knee involvement

The integrity and strength of the posterior cruciate ligament (PCL) in the rheumatoid knee are known to be suboptimal. However, the results of PCL-substituting total knee arthroplasty in rheumatoid patients are not well documented. We reviewed 86 PCL-substituting total knee arthroplasties in 52 rheumatoid patients with grade IV or V radiographic disease. The mean age at surgery was 41.9 years. All patients underwent follow-up evaluation for an average of 7.8 years. Revision was performed for 1 knee because of aseptic loosening of the tibial component, and for 3 knees because of deep infection. An isolated insert exchange was performed on one knee. Using revision of any component for aseptic loosening or radiographic loosening as the end point, the mean 10-year survival rate was 94.0%.

Cementless total knee arthroplasty in patients 50 years or younger

Total knee arthroplasty now is being advocated for use in younger patients with posttraumatic and rheumatoid arthritis. Advances in technology, design, and materials potentially have allowed for more predictable results. There has been continued interest in cementless fixation for use in younger patients. Between 1986 and 1998, 75 total knee replacements in 57 patients 50 years or younger were done. All surgeries were done by one surgeon (AAH). There were 35 left knees and 40 right knees. The average age of the patients was 42 years (range, 31-50 years). Followup averaged 111 months. Preoperative range of motion was 5 degrees to 106 degrees and postoperative range of motion was 2 degrees to 113 degrees. Modified Hospital for Special Surgery knee scores improved from an average of 67 points preoperatively to an average of 97 points postoperatively. The majority of the diagnoses were posttraumatic arthritis or osteoarthritis (57%), indicating a young, active group of patients. There were two infections and 12 polyethylene exchanges. There were no revisions for loosening or implant failure. There was a correlation between prior knee surgeries and the need for a manipulation. Radiographically, there were no loose implants. Cementless fixation in the young patient with high physical demands was clinically reliable.

Total knee arthroplasty in patients </=50 years old

Thirty patients (30 knees) who underwent total knee arthroplasty at age </=50 were reviewed. These patients were operated on between July 1, 1991, and May 1, 1995, with final follow-up evaluation at a mean of 86 months (range, 60-107 months). At final evaluation, 18 knees (60%) had excellent Knee Society objective scores, 11 knees (37%) had good scores, and 1 knee (3%) had a poor score. There were no statistically significant differences in Knee Society objective scores among the cemented group (mean, 88 points), hybrid group (mean, 88 points), and noncemented group (mean, 90 points). One patient (3%) had a revision because of unexplained pain. In the other knees, there was no radiographic evidence of progressive loosening, lucencies, or change in position or alignment of the prosthesis. Total knee arthroplasty of this design, at least for the time period studied (7-year mean follow-up), has a high rate of success in patients who are </=50 years old.