Influence of social support on return to work after total hip or total knee arthroplasty: a prospective multicentre cohort study.

OBJECTIVES: There is strong evidence that social support is an important determinant of return to work (RTW). Little is known about the role of social support in RTW after total hip or knee arthroplasty (THA/TKA). Objective was to examine the influence of preoperative and postoperative perceived social support on RTW status 6 months postoperatively. DESIGN: A prospective multicentre cohort study was conducted. SETTING: Orthopaedic departments of four Dutch medical centres; a tertiary university hospital, two large teaching hospitals and a general hospital. PARTICIPANTS: Patients planned to undergo THA/TKA, aged 18-63 and employed preoperatively were included. MAIN OUTCOME MEASURES: Questionnaires were filled out preoperatively and 3 and 6 months postoperatively and included questions to assess patients' perceived social support targeting three sources of social support: from home (friends, family), from work (coworkers, supervisors) and from healthcare (occupational physician, general practitioner, other caregivers). Control variables included age, gender, education, type of arthroplasty and comorbidities. RTW was defined as having fully returned to work 6 months postoperatively. Univariate and multivariate logistic regression analyses were conducted. RESULTS: Enrolled were 190 patients (n=77 THA, n=113 TKA, median age was 56 years, 56% women). The majority returned to work (64%). Preoperatively, social support from the occupational physician was associated with RTW (OR 2.53, 95% CI 1.15 to 5.54). Postoperatively, social support from the occupational physician (OR 3.04, 95% CI 1.43 to 6.47) and the supervisor (OR 2.56, 95% CI 1.08 to 6.06) was associated with RTW. CONCLUSIONS: This study underscores the importance of work-related social support originating from the occupational physician and supervisor in facilitating RTW after primary THA/TKA, both preoperatively and postoperatively. Further research is needed to confirm our results and to understand the facilitating role of social support in RTW, as arthroplasty is being performed on a younger population for whom work participation is critical.

Psychosocial Working Conditions Play an Important Role in the Return-to-Work Process After Total Knee and Hip Arthroplasty.

Purpose Both personal and work-related factors affect return to work (RTW) after total knee arthroplasty (TKA) and total hip arthroplasty (THA). Little is known about work-related factors associated with the recovery process. This study aimed to determine which work-related factors are associated with time to RTW for both TKA and THA patients. Methods A prospective multicenter survey study was conducted that included patients aged 18-63, had a paid job and were scheduled to undergo primary TKA/THA. Surveys were completed preoperatively, 6 weeks, and 3, 6, and 12 months postoperatively, and included four domains of work-related factors: work characteristics, physical working conditions, psychosocial working conditions and work adjustments. Control variables included age, sex, education, and comorbidity. Time to RTW was defined as days from surgery until RTW. Multivariate linear regression analyses were conducted separately for TKA/THA patients. Results Enrolled were 246 patients (n = 146 TKA, n = 100 THA, median age 56 years, 57% female). Median time to RTW was 79 days (IQR 52.0-146.0). Mainly physical tasks (TKA: B 58.2, 95%CI 9.5-106.8; THA: B 52.1, 95%CI 14.1-90.2) and a combination of physical and mental tasks (TKA: B 50.2, 95%CI 6.4-94.0; THA B 54.0, 95%CI 24.2-83.7) were associated with longer time to RTW after both TKA and THA. More possibilities for personal job development (B - 12.8, 95%CI - 25.3-0.4) and more work recognition (B - 13.2, 95%CI - 25.5 to - 0.9) were significantly associated with shorter time to RTW after TKA. Higher quality of supervisor leadership (B - 14.1, 95%CI - 22.2 to - 6.0) was significantly associated with shorter time to RTW after THA. Conclusion The findings of this study stress the importance of psychosocial working conditions, besides type of job tasks, in RTW after TKA/THA. Further research on work-related factors is needed, as arthroplasty is being performed on an increasingly younger population of knee and hip OA patients for whom participating in work is of critical importance.

Two-year recovery courses of physical and mental impairments, activity limitations, and participation restrictions after total knee arthroplasty among working-age patients.

PURPOSE: Total knee arthroplasty is increasingly performed on working-age individuals, but little is known about their recovery process. Therefore this study examined recovery courses of physical and mental impairments, activity limitations and participation restrictions among working-age total knee arthroplasty recipients. Associated sociodemographic and health-related factors were also evaluated. MATERIALS AND METHODS: A prospective study among working total knee arthroplasty patients (aged <65 years) (n = 146). Surveys were completed preoperatively and 6 weeks and 3, 6, 12, and 24 months postoperatively. Outcomes represented domains of the International Classification of Functioning, that is, physical impairments (pain, stiffness, vitality), mental impairments (mental health, depressive symptoms), activity limitations (physical functioning), and participation restrictions (social-, work functioning, working hours). Covariates included age, gender, education, home situation, body mass index, and comorbidity. RESULTS: Largest improvements in physical and mental impairments and activity limitations were observed until 3 months postoperatively. Participation in social roles improved early after surgery, and improvements in work participation occurred from 6 to 12 months. Older age, being male and fewer comorbidities were associated with better recovery courses. CONCLUSION: Working-age total knee arthroplasty patients recover soon from physical and mental impairments, activity limitations, and participation in social roles, but participation at work occurs later. Younger patients, females, and those with musculoskeletal comorbidities appear at risk for suboptimal recovery after total knee arthroplasty.Implications for rehabilitationAn increasing number of working-age patients are asking for total knee arthroplasty and have high expectations of total knee arthroplasty, in particular, to participate in the workforce again;Recovery after total knee arthroplasty (TKA) does not occur in the short term and is not limited to clinical improvements for working-age TKA recipients only, as an important part of recovery, that is, participation occurs in the long term (>6 months);Closer collaboration between occupational physicians and orthopedic surgeons might result in increased and earlier ability to work full contractual hours;Rehabilitation after TKA should focus on patients with multiple comorbidities, whereby musculoskeletal diseases may even need additional preoperative treatment to optimize outcomes and prevent work disability.

Which patients improve most after total hip arthroplasty? Influence of patient characteristics on patient-reported outcome measures of 22,357 total hip arthroplasties in the Dutch Arthroplasty Register.

BACKGROUND: Patient-reported outcome measures (PROMs) after total hip arthroplasty (THA), can be influenced by patient characteristics (case-mix factors). We used the Dutch Arthroplasty Register (LROI) to determine the effect of case-mix on improvement of PROMs after primary THA. METHODS: We included all primary THAs (n = 22,357) performed in the Netherlands between 2014 and 2018. The Hip disability and Osteoarthritis Outcome Score Physical function short form (HOOS-PS), Oxford Hip Score (OHS), EQ-5D index score and thermometer, and Numeric Rating Scales (NRS) measuring pain during activities and at rest, were recorded. The difference between preoperative and 3- and 12-month postoperative scores was calculated (delta-PROM) and used as primary outcome variable. Multivariable linear regression was used to examine the association between patient characteristics (age, sex, ASA score, body mass index (BMI), Charnley class, smoking, and previous operations to the affected hip) and PROMs. Cohens' d was used to measure effect size. RESULTS: Postoperative improvement (delta-PROM) on HOOS-PS, OHS, EQ-5D, and pain relief were significantly higher in patients <60 years, in patients with female gender, a high ASA score (III-IV), a BMI >30 kg/m2, and patients without a previous operation to the hip. Cohen's d indicated clinically small differences (0.2). CONCLUSIONS: Patients benefiting most in terms of postoperative improvement of self-reported physical functioning, pain relief and quality of life after primary THA were young, female, with a high ASA or BMI score, and without previous operations to the hip.

Dutch Guideline on Knee Arthroscopy Part 2: non-meniscus intra-articular knee injury: a multidisciplinary review by the Dutch Orthopaedic Association.

Background and purpose - A guideline committee of medical specialists and a physiotherapist was formed on the initiative of the Dutch Orthopedic Association (NOV) to update the Guideline Arthroscopy of the Knee: Indications and Treatment 2010. This next Guideline was developed between June 2017 and December 2019. In part 1 we focused on the meniscus; this part 2 addresses all other aspects of knee arthroscopy.Methods - The guideline was developed in accordance with the criteria of the AGREE instrument (AGREE II: Appraisal of Guidelines for Research and Evaluation II) with support of a professional methodologist from the Dutch Knowledge Institute of Medical Specialists. The scientific literature was searched and systematically analyzed. Conclusions and recommendations were formulated according to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) method. Recommendations were developed considering the balance of benefits and harms, the type and quality of evidence, the values and preferences of the people involved, and the costs.

Dutch Guideline on Knee Arthroscopy Part 1, the meniscus: a multidisciplinary review by the Dutch Orthopaedic Association.

Background and purpose - A guideline committee of medical specialists and a physiotherapist was formed on the initiative of the Dutch Orthopedic Association (NOV) to update the guideline Arthroscopy of the Knee: Indications and Treatment 2010. This next guideline was developed between June 2017 and December 2019. In this Part 1 we focus on the meniscus, in Part 2 on all other aspects of knee arthroscopy.Methods - The guideline was developed in accordance with the criteria of the AGREE instrument (AGREE II: Appraisal of Guidelines for Research and Evaluation II) with support of a professional methodologist from the Dutch Knowledge Institute of Medical Specialists. The scientific literature was searched and systematically analyzed. Conclusions and recommendations were formulated according to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) method. Recommendations were developed considering the balance of benefits and harms, the type and quality of evidence, the values and preferences of the people involved, and the costs.

Patient Characteristics Influence Revision Rate of Total Hip Arthroplasty: American Society of Anesthesiologists Score and Body Mass Index Were the Strongest Predictors for Short-Term Revision After Primary Total Hip Arthroplasty.

BACKGROUND: Outcome and survival after primary total hip arthroplasty (THA) can be affected by patient characteristics. We examined the effect of case-mix on revision after primary THA using the Dutch Arthroplasty Register. METHODS: Our cohort included all primary THAs (n = 218,214) performed in patients with osteoarthritis in the Netherlands between 2007 and 2018. Multivariable logistic regression analysis was used to calculate the difference in survivorship in patients with different patient characteristics (age, gender, American Society of Anesthesiologists [ASA] score, body mass index [BMI], Charnley score, smoking, and previous operations to the hip). RESULTS: Case-mix factors associated with an increased risk for revision 1 year after THA were the following: a high ASA score (II and III-IV) (odds ratio [OR] 1.5, 95% confidence interval [CI] 1.1-2.0 and OR 3.0, 95% CI 1.7-5.3), a higher BMI (30-40 and >40) (OR 1.4, 95% CI 1.2-1.5 and OR 2.0, 95% CI 1.4-1.7), age ≥75 years (OR 1.5, 95% CI 1.1-2.0), and male gender (OR 1.3, 95% CI 1.2-1.4). A similar model for 3-year revision showed comparable results. High BMI (OR 1.9, 95% CI 1.3-2.9), a previous hip operation (OR 1.8, 95% CI 1.3-2.5), ASA III-IV (OR 1.2, 95% CI 1-1.6), and Charnley score C (OR 1.5, 95% CI 1.1-2.2) were associated with increased risk for revision. Main reasons for revision in obese and ASA II-IV patients were infection, dislocation, and periprosthetic fracture. Patients with femoral neck fracture and late post-traumatic pathology were more likely to be revised within 3 years, compared to osteoarthritis patients (OR 1.5, 95% CI 1.3-1.7 and OR 1.5, 95% CI 1.2-1.7). CONCLUSION: The short-term risk for revision after primary THA is influenced by case-mix factors. ASA score and BMI (especially >40) were the strongest predictors for 1-year revision after primary THA. After 3 years, BMI and previous hip surgery were independent risk factors for revision. This will help surgeons to identify and counsel high-risk patients and take appropriate preventive measures.

Similar Superior Patient-Reported Outcome Measures for Anterior and Posterolateral Approaches After Total Hip Arthroplasty: Postoperative Patient-Reported Outcome Measure Improvement After 3 months in 12,774 Primary Total Hip Arthroplasties Using the Anterior, Anterolateral, Straight Lateral, or Posterolateral Approach.

BACKGROUND: Patient-reported outcome measures (PROMs) are used to evaluate the outcome of total hip arthroplasty (THA). We determined the effect of surgical approach on PROMs after primary THA. METHODS: All primary THAs, with registered preoperative and 3 months postoperative PROMs were selected from the Dutch Arthroplasty Register. Based on surgical approach, 4 groups were discerned: (direct) anterior, anterolateral, direct lateral, and posterolateral approaches. The following PROMs were recorded: Hip disability and Osteoarthritis Outcome Score Physical function Short form (HOOS-PS); Oxford Hip Score; EQ-5D index score; EQ-5D thermometer; and Numeric Rating Scale measuring pain, both active and in rest. The difference between preoperative and postoperative scores was calculated (delta-PROM) and used as primary outcome measure. Multivariable linear regression analysis was performed for comparisons. Cohen's d was calculated as measure of effect size. RESULTS: All examined 4 approaches resulted in a significant increase of PROMs after primary THA in the Netherlands (n = 12,274). The anterior and posterolateral approaches were associated with significantly more improvement in HOOS-PS scores compared with the anterolateral and direct lateral approaches. Furthermore, the posterolateral and anterior approaches showed greater improvement on Numeric Rating Scale pain scores compared with the anterolateral approach. No relevant differences in delta-PROM were seen between the anterior and posterolateral surgical approaches. CONCLUSION: Anterior and posterolateral surgical approaches showed more improvement in self-reported physical functioning (HOOS-PS) compared with anterolateral and direct lateral approaches in patients receiving a primary THA. However, clinical differences were only small.

The effect of bearing type on the outcome of total hip arthroplasty.

Background and purpose - Alternative bearing surfaces such as ceramics and highly crosslinked polyethylene (HXLPE) were developed in order to further improve implant performance of total hip arthroplasties (THAs). Whether these alternative bearing surfaces result in increased longevity is subject to debate. Patients and methods - Using the Dutch Arthroplasty Register (LROI), we identified all patients with a primary, non-metal-on-metal THA implanted in the Netherlands in the period 2007-2016 (n = 209,912). Cumulative incidence of revision was calculated to determine differences in survivorship of THAs according to bearing type: metal-on-polyethylene (MoPE), metal-on-HXLPE (MoHXLPE), ceramic-on-polyethylene (CoPE), ceramic-on-HXLPE (CoHXLPE), ceramic-on-ceramic (CoC), and oxidized-zirconium-on-(HXL)polyethylene (Ox(HXL)PE). Multivariable Cox proportional hazard regression ratios (HRs) were used for comparisons. Results - After adjustment for confounders, CoHXLPE, CoC, and Ox(HXL)PE resulted in a statistically significantly lower risk of revision compared with MoPE after 9 years follow-up (HR =0.8-0.9 respectively, compared with HR =1.0). For small (22-28 mm) femoral head THAs, lower revision rates were found for CoPE and CoHXLPE (HR =0.9). In the 36 mm femoral head subgroup, CoC-bearing THAs had a lower HR compared with MoHXLPE (HR =0.7 versus 1.0). Crude revision rates in young patients (< 60 years) for CoHXLPE, CoC, and Ox(HXL)PE (HR =0.7) were lower than MoPE (HR =1.0). However, after adjustment for case mix and confounders these differences were not statistically significant. Interpretation - We found a mid-term lower risk of revision for CoHXLPE, CoC, and Ox(HXL)PE bearings compared with traditional MoPE-bearing surfaces.

Fatal Cobalt Toxicity after a Non-Metal-on-Metal Total Hip Arthroplasty.

This case illustrates the potential for systemic cobalt toxicity in non-metal-on-metal bearings and its potentially devastating consequences. We present a 71-year-old male with grinding sensations in his right hip following ceramic-on-ceramic total hip arthroplasty (THA). After diagnosing a fractured ceramic liner, the hip prosthesis was revised into a metal-on-polyethylene bearing. At one year postoperatively, X-rays and MARS-MRI showed a fixed reversed hybrid THA, with periarticular densities, flattening of the femoral head component, and a pattern of periarticular metal wear debris and pseudotumor formation. Before revision could take place, the patient was admitted with the clinical picture of systemic cobalt toxicity, supported by excessively high serum cobalt and chromium levels, and ultimately died. At autopsy dilated cardiomyopathy as cause of death was hypothesized. A third body wear reaction between ceramic remnants and the metal femoral head very likely led to excessive metal wear, which contributed systemic cobalt toxicity leading to neurotoxicity and heart failure. This case emphasizes that fractured ceramic-on-ceramic bearings should be revised to ceramic-on-ceramic or ceramic-on-polyethylene bearings, but not to metal-on-polyethylene bearings. We aim to increase awareness among orthopedic surgeons for clinical clues for systemic cobalt intoxication, even when there is no metal-on-metal bearing surface.

Preoperative characteristics of working-age patients undergoing total knee arthroplasty.

OBJECTIVE: Total Knee Arthroplasty (TKA) is performed more in working-age (<65 years) patients. Until now, research in this patient population has been conducted mainly among retired (≥65 years) patients. Aim of this study was therefore to describe demographic, physical, psychological and social characteristics of working TKA patients and to subsequently compare these characteristics with retired TKA patients and the general population. METHODS: A cross-sectional analysis. Preoperative data of 152 working TKA patients was used. These data were compared with existing data of retired TKA patients in hospital registers and with normative values from literature on the general population. Demographic, physical, psychological and social (including work) characteristics were analyzed. RESULTS: The majority (83.8%) of working TKA patients was overweight (42.6%) or obese (41.2%), a majority (72.4%) was dealing with two or more comorbidities, and most (90%) had few depressive symptoms. Mean physical activity level was 2950 minutes per week. Compared to the retired TKA population, working TKA patients perceived significantly more stiffness and better physical functioning and vitality, were more physically active, and perceived better mental health. Compared to the general population working TKA patients perceived worse physical functioning, worse physical health and better mental health, and worked fewer hours. CONCLUSION: This study shows that a majority of working TKA patients are overweight/obese, have multiple comorbidities, but are highly active in light-intensity activities and have few depressive symptoms. Working patients scored overall better on preoperative characteristics than retired patients, and except for physical activity scored overall worse than the general population.

Occlusion of brachial pseudoaneurysm after periprosthetic humerus fracture.

Pseudoaneurysms of the brachial artery are rare and most often occur after a penetrating injury. The incidence of periprosthetic humerus fractures is low, and surgical treatment can be demanding. The treatment of choice for an occluded pseudoaneurysm of the brachial artery is saphenous vein bypass. In this article, we report the case of a 73-year-old woman who presented with an occluded pseudoaneurysm of the brachial artery sustained after a neglected periprosthetic humerus fracture. A saphenous vein bypass was performed after removal of the distal tip of the prosthesis. Patency was observed 3 months after surgery. This case shows malunion of a neglected periprosthetic humerus fracture and a good result after saphenous vein bypass.

Multi-modality imaging of transient osteoporosis of the hip.

Transient osteoporosis of the hip (TOH), also referred to as bone marrow edema syndrome (BMES) of the femoral head and neck, is an uncommon and therefore underdiagnosed benign skeletal disorder, affecting primarily women, particularly in their last trimester of pregnancy, and middle-aged men. The disease is characterized by self-limiting hip pain and radiographically evident osteopenia, but these radiographic findings can sometimes be delayed. In the early phase, the main diagnostic dilemma lies in differentiating TOH from osteonecrosis of the femoral head (ONFH). Conventional radiographs, Tc-99m bone scans (multiphase, SPECT or SPECT/CT) and MRI scans from 10 male patients with 12 TOH episodes were retrospectively and independently reviewed by two nuclear medicine physicians and a musculoskeletal radiologist. The purpose was to identify a typical imaging pattern, and secondly, to reliably distinguish TOH from ONFH. In the early phase of TOH, conventional radiography of the hip could not sufficiently detect focal osteopenia. But in all 10 patients (mean age 45 years, range, 34-62), bone scans and MRI scans demonstrated a similar pattern of diffuse hyperaemia, bony uptake, and bone marrow edema in the femoral head and neck, extending to and ending with a sharp demarcation at the intertrochanteric region. Additionally, neither SPECT nor SPECT/CT nor MRI revealed any cold area or crescent-shaped subchondral defect in the femoral head, indicating ONFH. In some cases there was a joint effusion in varying degree. In 9 patients, an uneventful recovery was eventually observed. Scintigraphically diffuse hyperaemic and/or homogeneous osseous uptake in femoral head and neck extending to the intertrochanteric region, as well as the recently introduced term transient bone marrow edema syndrome (BMES) of the hip on MRI, are probably both expressions of the same pathophysiological mechanism, and pathognomonic for TOH. Hopefully, recognizing this highly specific imaging pattern will exclude in the future more aggressive skeletal diseases like ONFH, severe arthritis, osteomyelitis or even malignancy.

Value of magnetic resonance arthrography in post-traumatic anterior shoulder instability prior to arthroscopy: a prospective evaluation of MRA versus arthroscopy.

PURPOSE: This prospective study was designed to evaluate the value of magnetic resonance arthrography (MRA) after traumatic anterior shoulder instability prior to arthroscopy. METHODS: Patients included had two or more shoulder dislocations, at least the first being traumatic. MRA images were scored for Hill Sachs lesions, superior labral anterior posterior (SLAP) lesions, rotator cuff tears, glenohumeral ligament (GHL) lesions and Bankart lesions. Consequently, a standardized shoulder arthroscopy was performed. Five surgeons were involved in the study, initially blinded to the MRA results. MRA and arthroscopic findings were compared. Interobserver agreement was calculated by using Cohen's Kappa coefficients (κ). RESULTS: Eighteen patients (13 male, 5 female) were included (mean age 26.1 years). Hill Sachs lesions demonstrated fair agreement (κ = 0.33) whereas for SLAP lesions moderate agreement was calculated (κ = 0.43). On MRA, four partial thickness rotator cuff lesions were seen, not being stated by arthroscopy. GHL lesions were described on MRA in 15 patients; only two patients turned out to have GHL lesions at arthroscopy. Two arthroscopically diagnosed Bankart lesions which needed surgical treatment were not detected by MRA (moderate agreement, κ = 0.47). CONCLUSIONS: In patients with post-traumatic anterior glenohumeral instability MRA shows many lesions that can not be confirmed by arthroscopy and therefore do not have therapeutical consequences. On the other hand some labral lesions which do need surgical treatment are not detected on MRA. At least from this study, it can be concluded that MRA has limited value prior to the arthroscopic treatment of post-traumatic shoulder instability.

Expanding role of 18F-fluoro-D-deoxyglucose PET and PET/CT in spinal infections.

(18)F-fluoro-D -deoxyglucose positron emission tomography ([(18)F]-FDG PET) is successfully employed as a molecular imaging technique in oncology, and has become a promising imaging modality in the field of infection. The non-invasive diagnosis of spinal infections (SI) has been a challenge for physicians for many years. Morphological imaging modalities such as conventional radiography, computed tomography (CT), and magnetic resonance imaging (MRI) are techniques frequently used in patients with SI. However, these methods are sometimes non-specific, and difficulties in differentiating infectious from degenerative end-plate abnormalities or postoperative changes can occur. Moreover, in contrast to CT and MRI, FDG uptake in PET is not hampered by metallic implant-associated artifacts. Conventional radionuclide imaging tests, such as bone scintigraphy, labeled leukocyte, and gallium scanning, suffer from relatively poor spatial resolution and lack sensitivity, specificity, or both. Initial data show that [(18)F]-FDG PET is an emerging imaging technique for diagnosing SI. [(18)F]-FDG PET appears to be especially helpful in those cases in which MRI cannot be performed or is non-diagnostic, and as an adjunct in patients in whom the diagnosis is inconclusive. The article reviews the currently available literature on [(18)F]-FDG PET and PET/CT in the diagnosis of SI.

Functional changes in articular cartilage after meniscal allograft transplantation: a quantitative histochemical evaluation in rabbits.

PURPOSE: To evaluate quantitatively functional changes in articular cartilage after immediate and delayed meniscus transplantation in rabbits. TYPE OF STUDY: Experimental study. METHODS: Thirty rabbits were divided into 5 groups: groups A and C were subjected to meniscectomy only, groups B and D underwent meniscal transplantation immediately after meniscectomy, and group E had delayed transplantation 6 weeks after meniscectomy. Six nonoperated knees served as controls. Functional changes in articular cartilage were examined at 6 weeks (groups A, B) and 1 year (groups C, D, E, controls) after surgery by measuring proteoglycan content of the extracellular matrix as a measure of its quality and lactate dehydrogenase (LDH) activity in chondrocytes as a measure of their vitality. RESULTS: At 6-week and 1-year follow-up, no significant differences were found between the immediate transplant group and postmeniscectomy group. The delayed transplant group showed a significantly decreased proteoglycan content compared with the postmeniscectomy group. No significant differences in cellular LDH activity were found between the immediate transplant group and postmeniscectomy group at 6 weeks and 1 year. However, the delayed transplant group showed a significant decrease in LDH activity compared with the postmeniscectomy group. CONCLUSIONS: Immediate meniscal transplantation in rabbits did not significantly reduce degenerative changes of articular cartilage in comparison with meniscectomy on a short-term and long-term basis, whereas delayed transplantation led to more degenerative changes than meniscectomy. CLINICAL RELEVANCE: Before meniscus transplantation can be considered as an alternative to meniscectomy in clinical practice, it has to be determined whether this procedure has any protective effect on articular cartilage on the long term.

Histologic changes in articular cartilage after medial meniscus replacement in rabbits.

PURPOSE: Meniscal allografts show capsular ingrowth, but it remains to be established whether meniscal transplantation can prevent long-term degeneration of articular cartilage. This study examined whether immediate or delayed transplantation of the medial meniscus can protect the knee from degenerative changes. TYPE OF STUDY: Experimental study. METHODS: Thirty-five rabbits were divided into 5 groups. Three rabbits developed infective arthritis and were excluded from the study. Group A (6 animals) and group C (6 animals) had meniscectomy only; group B (7 animals) and group D (6 animals) underwent meniscal transplantation immediately after meniscectomy; group E (7 animals) had delayed transplantation 6 weeks after meniscectomy. Six nonoperated knees served as controls. Histologic changes of the articular cartilage were examined 6 weeks (groups A, B) and 1 year (groups C, D, E, controls) after surgery. RESULTS: All operated groups showed more histologic changes than the control group (P < .00001 for both the medial tibial plateau and medial femoral condyle in all groups). At 6 weeks follow-up, no differences were found between the postmeniscectomy group and the transplanted group. At 1 year, immediately transplanted knees showed less degenerative changes than meniscectomized knees (P < .0001 for medial tibial plateau and P < .005 for medial femoral condyle). Delayed transplantation resulted in more degenerative changes than both meniscectomy only and immediate transplantation (for both comparisons, P < .00001 for both medial tibial plateau and medial femoral condyle). CONCLUSIONS: Immediate meniscal transplantation in rabbits has a protecting effect on articular cartilage for the long-term whereas delayed transplantation leads to even more degenerative changes than meniscectomy only. CLINICAL RELEVANCE: If these results are applicable to humans, they would support immediate, not delayed, transplantation after removal of a meniscus.

Meniscal allograft transplantation--part II: alternative treatments, effects on articular cartilage, and future directions.

Abstract Meniscal allograft transplantation in clinical practice has progressed to a point where short-term relief of pain may be expected. However, it remains to be established whether a transplanted meniscus can prevent degenerative changes in the knee joint in the long term. In part II of this Current Concepts review, meniscus regeneration and alternative treatments to meniscal allograft transplantation are evaluated as well as the effect of meniscal allograft transplantation on articular cartilage. Remaining questions and future directions are considered in a final discussion. It can be concluded that considerably more data and evaluations of results are needed to determine whether meniscal allograft transplantation in humans will be successful in protecting and preserving articular cartilage after meniscectomy in the long term.

Meniscal allograft transplantation--part I: background, results, graft selection and preservation, and surgical considerations.

Removal of the meniscus leads to progressive degenerative arthritis of the knee on a long-term basis. Therefore, meniscal allograft transplantation has been proposed as an alternative to meniscectomy. Although several experimental and clinical studies have documented that meniscal allografts show capsular ingrowth in meniscectomized knees, it remains to be established whether meniscal allograft transplantation can prevent degenerative changes after meniscectomy. Part 1 of this Current Concepts review will discuss the function, anatomy, and composition of the meniscus, followed by the history of surgery of meniscal tears and the healing of meniscal allografts in experimental and clinical studies. In addition, issues concerning preservation techniques, immunological reactions, sizing, disease transmission, indications, surgical technique, graft fixation, rehabilitation, and complications, will be taken into consideration. It can be concluded that the use of meniscal allografts in clinical practice has progressed to a point where relief of pain may be expected for the short-term.

Scintigraphic assessment of rabbit knee joints after meniscal allograft transplantation.

PURPOSE: It has been shown that meniscal allografts show capsular ingrowth in meniscectomized knees. However, it remains to be established whether a transplanted meniscus can prevent degenerative changes in the long term. In the present study, scintigraphy was used to evaluate degenerative changes in rabbit knees after meniscectomy only and after meniscectomy followed by immediate or delayed meniscus transplantation. TYPE OF STUDY: Experimental study. METHODS: Twenty-eight rabbits were divided into 4 groups. Three rabbits developed infective arthritis and were excluded from the study. In group A (6 animals), 2 rabbits underwent medial meniscectomy, 3 rabbits underwent transplantation with a freshly harvested medial meniscal allograft immediately after meniscectomy, and 1 rabbit underwent a sham operation. In group B (6 rabbits) medial meniscectomy was performed. Group C (6 rabbits) underwent meniscal transplantation immediately after meniscectomy. Group D (7 rabbits) underwent delayed allograft transplantation at 6 weeks after meniscectomy. The animals in group A underwent scintigraphy at 6 weeks after surgery. In the other groups, scintigraphy was performed at 1-year follow-up. Contour changes of the knee joints and uptake of radiolabeled diphosphonate in the subchondral bone were evaluated. RESULTS: No animals in group A showed any abnormalities scintigraphically. Medial compartment changes in group B were more pronounced than in group C, but this difference was not statistically significant. A significant increase in contour changes of the femoral condyle was seen in group D. CONCLUSIONS: Immediate meniscal allograft transplantation did not result in a significant protecting effect on articular cartilage against osteoarthritic degeneration on a long-term basis. Delayed meniscal transplantation revealed even more degenerative changes of articular cartilage than meniscectomy without transplantation.