Patella height measurements in patients with patellofemoral instability: the power to predict patella height indices.

INTRODUCTION: Numerous indices for patella height measurement are described in the literature; however, there is not a universally accepted 'gold standard'. Choice of indices varies depending on personal preference and previous experience, making it difficult to compare results between studies. The aims of this study were to assess the correlation between different patella height indices and generate statistically derived formulae that can be used to predict the value of one patella height ratio when another is known. MATERIALS AND METHODS: Patients with patellofemoral instability were radiologically evaluated using both X-ray and Magnetic Resonance Imaging (MRI) of the knee. Two observers measured six validated patella height indices at two separate time intervals. All measurements were aggregated together and a mean average for each patella height ratio was calculated. These results were then statistically analysed using Pearson product-moment correlation and linear regression tests. RESULTS: Forty-four patients were included in the study. A statistically significant correlation was found between the majority of patella height ratios. On X-ray, the strongest correlation (r = 0.92, p < 0.001) and regression (R2 = 0.85, p < 0.001) coefficients were between the Blackburne-Peel and Caton-Dechamps ratios, with the formula; CD = 0.20 + (0.95xBP). On MRI, the strongest correlation (r = - 0.84, p < 0.001) and regression (R2 = 0.71, p < 0.001) coefficients were between the Patellophyseal index and Patellotrochlear index, with the formula; PP = 1.02-(1.10xPT). CONCLUSION: The formulae produced in this study can predict the value of one patella height ratio when the results of another are known. This could facilitate systematic reviews and meta-analyses by allowing the pooling together of data from many studies.

Impact of age on clinical outcomes in anterior cruciate ligament reconstruction.

BACKGROUND: Anterior cruciate ligament reconstruction (ACLR) is a common procedure for symptomatic ACL injuries. Age is often factored into clinical decision making and can influence the choice of conservative management over surgical intervention. The aim of this study was to investigate the effect of chronological age on the clinical outcome following ACLR. METHOD: Six validated patient-reported outcome measures (PROM) were used to collect pre-operative and post-operative scores from patients with ACL rupture undergoing ACLR. Data were stratified pertaining to the patient's age at the time of surgery to compare the Younger Group (under 40 years) with the Older Group (over 40 years). RESULTS: A total of 45 patients were included in this study. Pre-operatively the Younger Group (n = 32) had significantly better Lysholm (p = 0.016), Tegner (p = 0.001), Knee Injury and Osteoarthritis Outcome Score (KOOS) Activities of Daily Living (ADL) sub-score (p = 0.003) and International Knee Documentation Committee (IKDC) score (p = 0.014) as compared to the Older Group (n = 13). Post-operatively, there was no significant difference (p > 0.05) between the two groups as all the PROM scores were comparable except for the Tegner score (p = 0.02), where younger patients had higher activity levels. Significant inverse correlations were only found between age and Tegner score (rho = - 0.58, p < 0.001) and KOOS Sport and Recreation sub-score (rho = - 0.33, p = 0.038). CONCLUSION: ACLR is a clinically successful treatment strategy for patients of all ages. Thus, age should not be used in isolation to determine patient suitability.

Anterior cruciate ligament reconstruction: Effect of graft tunnel position on early to mid-term clinical outcomes.

BACKGROUND: Patient reported outcome measures (PROMs) can be used to assess knee function following anterior cruciate ligament (ACL) reconstruction. Intra-operatively, femoral and tibial tunnels are created to accommodate the new ACL graft. It is postulated that there is an optimum position and orientation of these tunnels and that outcomes from this procedure are affected by their position. AIM: To evaluate the influence of graft tunnel position on early to mid-term clinical outcomes following ACL reconstruction. METHODS: Six PROMs were collected following ACL reconstruction which included the Knee Injury and Osteoarthritis Outcome Score (KOOS), International Knee Documentation Committee, Lysholm, Tegner, EuroQol-5 Dimension-5 level, and Short Form 12-item Health Survey. A total of 8 radiological parameters were measured from post-operative X-rays relating to graft tunnel positions. This data was analysed to assess for any correlations between graft tunnel position and post-operative PROMs. RESULTS: A total of 87 patients were included in the study with a mean post-operative follow-up of 2.3 years (range 1 to 7 years). Posterior position of tibial tunnel was associated with improved KOOS quality of life (rho = 0.43, P = 0.002) and EQ-5D VAS (rho = 0.36, P = 0.010). Anterior position of EndoButton femoral tunnel was associated with an improved EQ-5D index (rho = -0.38, P = 0.028). There were no other significant correlations between any of the other radiological parameters and PROM scores. CONCLUSION: Overall, graft tunnel position had very little correlation with clinical outcomes following ACL reconstruction. A few (posterior) tibial tunnel and (anterior) EndoButton femoral tunnel measurements were associated with better PROMs.

Unicompartmental knee arthroplasty vs high tibial osteotomy for knee osteoarthritis: A comparison of clinical and radiological outcomes.

BACKGROUND: Unicompartmental knee arthroplasty (UKA) and high tibial osteotomy (HTO) are well-established operative interventions in the treatment of knee osteoarthritis. However, which intervention is more beneficial to patients with knee osteoarthritis remains unknown and a topic of much debate. Simultaneously, there is a paucity of research assessing the relationship between radiographic parameters of knee joint alignment and patient-reported clinical outcomes, preoperatively and following HTO or UKA. AIM: To compare UKAs and HTOs as interventions for medial-compartment knee osteoarthritis: Examining differences in clinical outcome and investigating the relationship of joint alignment with respect to this. METHODS: This longitudinal observational study assessed a total of 42 patients that had undergone UKA (n = 23) and HTO (n = 19) to treat medial compartment knee osteoarthritis. Patient-reported outcome measures (PROMs) were collected to evaluate clinical outcome. These included two disease-specific (Knee Injury and Osteoarthritis Outcome Score, Oxford Knee Score) and two generic (EQ-5D-5L, Short Form-12) PROMs. The radiographic parameters of knee alignment assessed were the: Hip-knee-ankle angle, mechanical axis deviation and angle of Mikulicz line. RESULTS: Statistical analyses demonstrated significant (P < 0.001), preoperative to postoperative, improvements in the PROM scores of both groups. There were, however, no significant inter-group differences in the postoperative PROM scores of the UKA and HTO group. Several significant correlations associated a more distolaterally angled Mikulicz line with worse knee function and overall health preoperatively (P < 0.05). Postoperatively, two clusters of significant correlations were observed between the disease-specific PROM scores and knee joint alignment parameters (hip-knee-ankle angle, mechanical axis deviation) within the HTO group; yet no such associations were observed within the UKA group. CONCLUSION: UKAs and HTOs are both efficacious operations that provide a comparable degree of clinical benefit to patients with medial compartment knee osteoarthritis. Clinical outcome has a limited association with radiographic parameters of knee joint alignment postoperatively; however, a more distolaterally angled Mikulicz line appears associated with worse knee function/health-related quality of life preoperatively.

Anthropometric measures of obesity in patients with knee joint pathology: Body surface area versus body mass index.

BACKGROUND: Obesity is quantified using body mass index. Body surface area may provide a superior and more anthropometric method of quantifying obesity in patients with musculoskeletal knee disease. This study compares the effect of weight, height, age and gender on body mass index and body surface area in a population with orthopaedic knee disease. METHODS: An observational cohort study was conducted of patients presenting with musculoskeletal knee disease. Associations between body mass index, body surface area, age, gender, height, weight and operative versus non-operative management were analysed. RESULTS: A total of 151 patients were included. Body surface area was more strongly correlated to weight than body mass index (r = 0.98, p < 0.001 versus r = 0.84, p < 0.001). Body surface area also reflects height which body mass index under presents (r = 0.65, p < 0.001 versus r = -0.08, p = 0.35). Body mass index and body surface area were correlated with one another (r = 0.70, p < 0.001). Age was inversely correlated with body surface area (r = -0.20, p = 0.013) but not body mass index (r = 0.05, p = 0.585). Body mass index did not differ between males and females (30.1 versus 30.9, p = 0.37); however, BSA scores were significantly higher in males than females (2.11 versus 1.91, p < 0.001). Neither body surface area nor body mass index scores influenced operative versus non-operative treatment. CONCLUSION: Body surface area could be a useful alternative to body mass index when considering obesity in patients with musculoskeletal knee pathology. Body surface area better reflects the effects of height, weight, age and gender than body mass index.

Evaluation of comorbidity scoring systems in patients undergoing knee arthroplasty.

BACKGROUND: Ageing populations are increasing the demand for knee arthroplasty. Concurrently, the prevalence of medical comorbidities are rising too. The Self-Administered Comorbidity Questionnaire was developed to provide a patient's assessment of their own comorbidities whereas the American Society of Anesthesiologists grades and the Charlson Comorbidity Index utilise clinical evaluation to objectively measure perioperative morbidity and mortality risk. The primary aim of this study was to compare Self-Administered Comorbidity Questionnaire scores with American Society of Anesthesiologists grades and Charlson Comorbidity Index scores. The secondary aim was to compare Self-Administered Comorbidity Questionnaire scores with knee outcome scores. METHODS: A single centre observational cohort study of patients with knee osteoarthritis undergoing elective knee arthroplasty. Preoperative evaluation included Self-Administered Comorbidity Questionnaire scores, American Society of Anesthesiologists grades, Charlson Comorbidity Index scores and validated patient-reported outcome measures specific to knee surgery. RESULTS: A total of 141 patients were included in this study. Self-Administered Comorbidity Questionnaire scores were directly correlated with American Society of Anesthesiologists grade (rho = 0.37, p < 0.001) and Charlson Comorbidity Index scores (rho = 0.19, p = 0.047). Individual American Society of Anesthesiologists grades had significantly different Self-Administered Comorbidity Questionnaire scores (p = 0.001). Self-Administered Comorbidity Questionnaire scores were specifically associated with hypertension, ischaemic heart disease, chronic obstructive pulmonary disease and the total number of comorbidities, but American Society of Anesthesiologists and Charlson Comorbidity Index scores were associated with more comorbidities. Overall, Self-Administered Comorbidity Questionnaire scores were inversely correlated with patient-reported outcome measure scores. CONCLUSION: Self-Administered Comorbidity Questionnaire scores are associated with increasing comorbidity in patients with symptomatic knee osteoarthritis; however, American Society of Anesthesiologists grades and Charlson Comorbidity Index scores had stronger and more abundant associations with comorbidities and patient-reported outcome measure scores. Self-Administered Comorbidity Questionnaires may complement but not replace current objective assessments of comorbidity when evaluating perioperative risk for knee arthroplasty.

Comparison of clinical outcomes between total hip replacement and total knee replacement.

BACKGROUND: Total hip replacements (THR) and total knee replacements (TKR) are effective treatments for severe osteoarthritis (OA). Some studies suggest clinical outcomes following THR are superior to TKR, the reason for which remains unknown. This study compares clinical outcomes between THR and TKR. AIM: To compare the clinic outcomes of THR anad TKR using a comprehensive range of patient reported outcome measures (PROMs). METHODS: A prospective longitudinal observational study of patients with OA undergoing THR and TKR were evaluated using a comprehensive range of generic and joint specific PROMs pre- and post-operatively. RESULTS: A total of 131 patients were included in the study which comprised the THR group (68 patients) and the TKR group (63 patients). Both groups demonstrated significant post-operative improvements in all PROM scores (P < 0.001). There were no significant differences in post-operative PROM scores between the two groups: Hip and Knee Osteoarthritis Outcome scores (P = 0.140), Western Ontario and McMaster Universities Osteoarthritis Index pain (P = 0.297) stiffness (P = 0.309) and function (P = 0.945), Oxford Hip and Knee Score (P = 0.076), EuroQol-5D index (P = 0.386) and Short-Form 12-item survey physical component score (P = 0.106). Subgroup analyses showed no significant difference (P > 0.05) between cruciate retaining and posterior stabilised prostheses in the TKR group and no significant difference (P > 0.05) between cemented and uncemented fixation in the THR group. Obese patients had poorer outcomes following TKR but did not significantly influence the outcome following THR. CONCLUSION: Contrary to some literature, THR and TKR are equally efficacious in alleviating the pain and disability of OA when assessed using a comprehensive range of PROMs. The varying knee prosthesis types and hip fixation techniques did not significantly influence clinical outcome. Obesity had a greater influence on the outcome following TKR than that of THR.

Inter- and intra-rater reliability of knee flexion angle measurements on X-ray and MRI.

Background: Range of motion (ROM) is an important aspect of orthopaedic patient assessment. It can be measured at the knee joint by determining the knee flexion angle (KFA) a patient can achieve at extremes of flexion and extension. As with any measurement, the accuracy and reliability of the method used determine its validity. The consistency of magnetic resonance imaging (MRI) scans as compared to the current gold standard of X-ray remains unknown in terms of KFA evaluation. The aim of this study was to assess and compare the reliability of measuring KFA between X-ray and MRI scans. Methods: This study included 80 patients (94 knees) who had attended a specialist knee clinic due to varying knee pathologies and undergone both X-ray and MRI scans. Lateral and T1-weighted sagittal imaging views (respectively) were used to measure KFA by two trained observers independently at two separate time points, 8 weeks apart. The data was then statistically analysed and intra- and inter-observer reliability calculated using the intraclass correlation coefficient (ICC). Results: The intra-observer reliability for X-ray was 0.96 (P<0.001) and that for MRI was 0.83 (P<0.001). The inter-observer reliability for X-ray was 0.99 (P<0.001) and that for MRI was 0.81 (P<0.001). All the intra-class correlation coefficients were graded as excellent in both the intra- and inter-observer reliability analysis. Overall, the mean KFA was notably higher on X-ray measurements than that on MRI scans. There was a statistically significant difference between Time 1 and Time 2 measurements (17.7° vs. 16.8°) for MRI data (P=0.022). No significant difference was found for X-ray measurements (46.4° vs. 45.6°) in this regard (P=0.182). Conclusions: Both X-ray and MRI allow KFA to be measured with an excellent degree of reliability. However, X-ray measurements were overall superior to that of MRI mainly due to the larger field of view of the visible on-screen image which more readily identifies the anatomical landmarks required to measure KFA.

Proprioception Analysis following Anterior Cruciate Ligament Reconstruction using Stabilometry: A Prospective, Longitudinal Study / Análise de propriocepção por estabilometria após a reconstrução do ligamento cruzado anterior: Um estudo prospectivo e longitudinal

Abstract Objective Commonly used methods for measuring proprioception have resulted in conflicting reports regarding knee proprioception with anterior cruciate ligament (ACL) rupture and the influence of ACL reconstruction. Methods One hundred subjects (50 patients with radiologically and arthroscopically confirmed unilateral ACL rupture and 50 normal controls) were assessed with regards to proprioception using dynamic single-leg stance postural stabilometry. Instrumented knee ligament laxity and knee outcome scores were also measured. Of the 50 patients in the ACL group, 34 underwent reconstruction and were reassessed postoperatively. Results There was a significant proprioceptive deficiency in the ACL group compared with their contralateral knee ( p < 0.001) and to the control group ( p = 0.01). There was asignificant improvement in knee proprioception following ACL reconstruction compared to preoperative findings ( p = 0.003). There was no correlation between ligament laxity measurements and outcome scores. A significant correlation was found preoperatively between outcome scores and proprioception measurements. This correlation was not found post-operatively. Pre-operative proprioception testing had asignificant correlation (r = 0.46) with post-operative proprioception ( p = 0.006). Conclusion Patients with an ACL rupture had a proprioceptive deficit which improved following ligament reconstruction. Knee outcome scores had a better correlation with proprioception than ligament laxity. Proprioception may be a superior objective measure than ligament laxity in quantifying functional knee deficits and outcomes in patients with ACL ruptures. Level of Evidence III Therapeutic Study; Prospective Longitudinal Case-Control Study.

Resumo Objetivo Os métodos comumente usados para medir a propriocepção resultaram em relatos conflitantes sobre a propriocepção do joelho com ruptura do ligamento cruzado anterior (LCA) e a influência da reconstrução do LCA. Métodos A propriocepção de 100 indivíduos (50 pacientes com ruptura unilateral do LCA confirmada à radiologia e artroscopia e 50 controles normais) foi avaliada por estabilometria postural dinâmica em apoio unipodal. A lassidão ligamentar do joelho instrumentado e suas pontuações de desfechos também foram medidas. Dos 50 pacientes do grupo LCA, 34 foram submetidos à reconstrução e reavaliados no período pós-operatório. Resultados O grupo LCA apresentou deficiência proprioceptiva significativa em relaçãoaojoelho contralateral ( p < 0,001) e ao grupo controle ( p = 0,01). A propriocepção do joelho melhorou de maneira significativa após a reconstrução do LCA em relação aos achados pré-operatórios ( p = 0,003). Não houve correlação entre as medidas de lassidão ligamentar e as pontuações de desfechos. Além disso, observamos uma correlação significativa entre as pontuações de desfechos e as medidas de propriocepção antes da cirurgia. Essa correlação não foi detectada no período pós-operatório. O teste pré-operatório de propriocepção teve correlação significativa ( r = 0,46) com a propriocepção pós-operatória ( p = 0,006). Conclusão Os pacientes com ruptura do LCA apresentaram déficit proprioceptivo que melhorou após a reconstrução ligamentar. As pontuações de desfecho do joelho tiveram melhor correlação à propriocepção do que a lassidão ligamentar. A proprio-cepção pode ser uma medida objetiva superior à lassidão ligamentar na quantificação de déficits funcionais e desfechos do joelho em pacientes com ruptura do LCA. Nível de Evidência III Estudo Terapêutico; Estudo de Caso-Controle Longitudinal Prospectivo.

Clinical Outcome Measures in Arthroscopic Meniscectomy: Clinician versus Patient Completed Knee Scores / Medidas de desfechos clínicos na meniscectomia artroscópica: Pontuações de joelho segundo médicos e pacientes

Abstract Objective The aim of the present study was to investigate the difference between clinician-completed and patient-completed outcome scores in detecting improvement following arthroscopic meniscectomy in patients with meniscal tears of the knee. Methods Thirty-four patients with meniscal tears were prospectively assessed using 9 clinical outcome measures. The five clinician-completed knee scores included the Tegner Activity Score, the Lysholm Knee Score, the Cincinnati Knee Score, the International Knee Documentation Committee (IKDC) Examination Knee Score, and the Tapper and Hoover Meniscal Grading Score. The four patient-completed knee scores included the IKDC Subjective Knee Score, the Knee Outcome Survey - Activities of Daily Living Scale (KOS-ADLS), the Short Form-12 Item Health Survey (SF-12), and the Knee Injury and Osteoarthritis Outcome Score (KOOS). Twenty-nine of the 34 patients underwent an arthroscopic meniscectomy and were reassessed with all 9 outcome scores upon their follow-up review. Results A significant longitudinal improvement was observed in 4 of the 5 clinician-completed scores (Tegner [p< 0.001], Lysholm [p= 0.004], Cincinnati [p = 0.002] and Tapper and Hoover [p< 0.001], but not in the IKDC Examination [p= 0.332]. However, the IKDC Subjective score (p= 0.021) was the only patient-completed score to demonstrate significant improvement postoperatively. Conclusion Overall, clinician-completed scoring systems were found to be inconsistent with those of patient-completed instruments. The mode of administering outcome measures can have a significant influence on the outcome results both for research and for clinical practice. A combination of both a clinician-completed with a patient-completed instrument may be a more balanced approach to assessing and quantifying meniscus tears and the outcome following arthroscopic meniscectomy.

Resumo Objetivo O objetivo do presente estudo foi investigar a diferença entre instrumentos de desfechos preenchidos por médicos e pacientes na detecção de melhora após a meniscectomia artroscópica para tratamento de rupturas de menisco. Métodos Trinta e quatro pacientes com rupturas de menisco foram avaliados de forma prospectiva usando 9 medidas de desfechos clínicos. Os cinco instrumentos de avaliação de joelho respondidos por médicos foram o Escore de Atividade de Tegner, o Escore de Joelho de Lysholm, o Escore de Joelho de Cincinnati, o Escore de Exame do Joelho do International Knee Documentation Committee (IKDC, na sigla em inglês) e o Escore de Classificação do Menisco de Tapper e Hoover. Os quatro instrumentos de avaliação do joelho respondidos por pacientes foram o Escore Subjetivo do Joelho do IKDC, a Pesquisa de Desfecho de Joelho - Escala de Atividades de Vida Diária (KOS-ADLS, na sigla em inglês), o Formulário Curto de Pesquisa em Saúde de 12 Itens (SF-12, na sigla em inglês) e o Escore de Desfecho de Osteoartrite e Lesões no Joelho (KOOS, na sigla em inglês). Vinte e nove dos 34 pacientes foram submetidos a uma meniscectomia artroscópica e reavaliados com todos os 9 instrumentos na sua consulta de acompanhamento. Resultados Uma melhora longitudinal significativa foi observada em 4 dos 5 instrumentos respondidos por médicos (Tegner [p< 0,001], Lysholm [p= 0,004], Cincinnati [p= 0,002] e Tapper e Hoover [p< 0,001], mas não no IKDC [p= 0,332]). Por outro lado, o Escore Subjetivo do Joelho do IKDC (p= 0,021) foi o único instrumento respondido por pacientes a demonstrar melhora pós-operatória significativa. Conclusão De modo geral, os instrumentos respondidos por médicos foram considerados inconsistentes em relação àqueles respondidos por pacientes. O modo de administração dos instrumentos pode ter influência significativa nos resultados, tanto para fins de pesquisa quanto para a prática clínica. A combinação de um instrumento respondido pelo médico com um instrumento respondido pelo paciente pode ser uma abordagem mais equilibrada para a avaliação e a quantificação das rupturas do menisco e do desfecho após a meniscectomia artroscópica.