Spindler, Kurt P

AbstractInfection is a rare occurrence after revision anterior cruciate ligament reconstruction (rACLR). Because of the low rates of infection, it has been difficult to identify risk factors for infection in this patient population. The purpose of this study was to report the rate of infection following rACLR and assess whether infection is associated with patient‐ and surgeon‐dependent risk factors. We reviewed two large prospective cohorts to identify patients with postoperative infections following rACLR. Age, sex, body mass index (BMI), smoking status, history of diabetes, and graft choice were recorded for each patient. The association of these factors with postoperative infection following rACLR was assessed. There were 1423 rACLR cases in the combined cohort, with 9 (0.6%) reporting postoperative infections. Allografts had a higher risk of infection than autografts (odds ratio, 6.8; 95% CI, 0.9–54.5; p = .045). Diabetes (odds ratio, 28.6; 95% CI, 5.5–149.9; p = .004) was a risk factor for infection. Patient age, sex, BMI, and smoking status were not associated with risk of infection after rACLR.

ObjectiveTo determine the 5‐year outcome of treatment for meniscal tear in osteoarthritis.MethodsWe examined 5‐year follow‐up data from the Meniscal Tear in Osteoarthritis Research trial (METEOR) of physical therapy versus arthroscopic partial meniscectomy. We performed primary intent‐to‐treat (ITT) and secondary as‐treated analyses. The primary outcome measure was the Knee Injury and Osteoarthritis Outcome Score (KOOS) pain scale; total knee replacement (TKR) was a secondary outcome measure. We used piecewise linear mixed models to describe change in KOOS pain. We calculated 5‐year cumulative TKR incidence and used a Cox model to estimate hazard ratios (HRs) for TKR, with 95% confidence intervals (95% CIs).ResultsThree hundred fifty‐one participants were randomized. In the ITT analysis, the KOOS pain scores were ~46 (scale of 0 [no pain] to 100 [most pain]) at baseline in both groups. Pain scores improved substantially in both groups over the first 3 months, continued to improve through the next 24 months (to ~18 in each group), and were stable at 24–60 months. Results of the as‐treated analyses of the KOOS pain score were similar. Twenty‐five participants (7.1% [95% CI 4.4–9.8%]) underwent TKR over 5 years. In the ITT model, the HR for TKR was 2.0 (95% CI 0.8–4.9) for subjects randomized to the arthroscopic partial meniscectomy group, compared to those randomized to the physical therapy group. In the as‐treated analysis, the HR for TKR was 4.9 (95% CI 1.1–20.9) for subjects ultimately treated with arthroscopic partial meniscectomy, compared to those treated nonoperatively.ConclusionPain improved considerably in both groups over 60 months. While ITT analysis revealed no statistically significant differences following TKR, greater frequency of TKR in those undergoing arthroscopic partial meniscectomy merits further study.

ObjectiveThe present study was undertaken to evaluate changes in knee magnetic resonance imaging (MRI) findings over the course of 18 months in subjects with osteoarthritic change and meniscal tear treated with arthroscopic partial meniscectomy (APM) or nonoperatively with physical therapy (PT).MethodsWe used 18‐month follow‐up data from the Meniscal Tear in Osteoarthritis Research Trial. MRI results were read with reference to the MRI Osteoarthritis Knee Score. We focused on 18‐month change in bone marrow lesions (BMLs), cartilage thickness, cartilage surface area, osteophyte size, effusion‐synovitis, and Hoffa‐synovitis. We used multinomial logistic regression to assess associations between MRI‐based changes in each feature and treatment type.ResultsA total of 351 subjects were randomized, and 225 had both baseline and 18‐month MRI results. In both treatment groups, patients experienced substantial changes in several MRI‐based markers. In 60% of the APM group, versus 33% of the PT group, cartilage surface area damage advanced in ≥2 subregions (adjusted odds ratio 4.2 [95% confidence interval 2.0–9.0). Patients who underwent APM also had greater advancement in scores for osteophytes and effusion‐synovitis. We did not find significant associations between treatment type and change in cartilage thickness, BMLs, or Hoffa‐synovitis.ConclusionThis cohort of patients with meniscal tear and osteoarthritis showed marked advancement in MRI‐based features over 18 months. Patients treated with APM showed more advancement in some features compared to those treated nonoperatively. The clinical relevance of these early findings is unknown and requires further study.

Background: Factors relating to the patient and anterior cruciate ligament (ACL) reconstruction may help to identify prognostic factors of long-term outcome after reconstruction. Purpose: To determine 10-year risk factors for inferior knee function after ACL reconstruction. Study Design: Cohort study; Level of evidence, 2. Methods: Prospectively collected data from the Swedish National Knee Ligament Register were extracted for patients who underwent ACL reconstruction between January 2005 and December 2006. Patients who had no data at the 10-year follow-up for the Knee injury and Osteoarthritis Outcome Score (KOOS) were excluded. Multivariable proportional odds regression modeling was used to assess 10-year patient- and surgery-related risk factors across all the KOOS subscales and the KOOS 4 (mean score of 4 subscales: pain, knee-related symptoms, function in sport and recreation, and knee-related quality of life). Results: A total of 874 (41%) patients were included (male, 51.5%; median age at the time of ACL reconstruction, 27.5 years [range, 11.2-61.5 years]). An increase in the severity of concomitant articular cartilage injuries resulted in a reduced KOOS on 4 subscales (odds ratio, 0.64-0.80; P < .05). A higher preoperative KOOS pain score increased the odds of a higher score on the pain, symptoms, and sport subscales and the KOOS 4 . In addition, a higher preoperative body mass index was a significant risk factor for lower scores on 3 KOOS subscales and the KOOS 4 . No patient- or surgery-related predictor was significant across all KOOS subscales. Conclusion: This 10-year risk factor analysis identified several factors that can affect long-term knee function after ACL reconstruction. Most risk factors were related to preoperative patient-reported outcome and potentially modifiable. On the other hand, most of the surgery-related risk factors were nonmodifiable. Nevertheless, this information may be helpful to physicians and physical therapists counseling patients on their expectations of outcome after ACL reconstruction.

Purpose To analyze failure rate in 2‐year increments to determine if graft choice changed over time and graft failure rate. Methods A prospective 2002‐2008 database was used to identify risk factors for anterior cruciate ligament (ACL) retear. Subjects who had primary ACL retear with no history of contralateral surgery and 2‐year follow‐up were included. Subjects who underwent a multiligament reconstruction were excluded. Graft type, age, sex, smoking status, body mass index, Marx activity level at index surgery, medial and lateral meniscus status at time of ACL retear, sport played after ACL reconstruction, and clinical site were evaluated. Analysis was repeated using 2002‐2003 (early) and 2007‐2008 (late) 2‐year databases. Analysis of variance with post hoc analysis was performed to detect significant differences in age and Marx score by graft type over time. Results Two‐year follow‐up for graft failure was obtained on 2,497 of 2,692 (93%) subjects. There were 112 of 2,497 (4.5%) ACL retears identified at 2‐year follow‐up. The only predictor that changed between early/late periods was allograft use. Allograft odds ratio decreased from 13.1 to 9.5 ( P < .01). Allografts were used in older patients (31‐40 years) and with lower Marx scores (10‐8) from early to late periods. The mean age of subjects who received bone–patellar tendon–bone autografts did not significantly change over time (22.8‐23.5). The mean age of subjects who received hamstring autografts fell (27.9‐25.5). The mean age of subjects who received allografts rose significantly (31.3‐39.8, P < .01). The mean Marx score of subjects who received bone–patellar tendon–bone and hamstring autografts did not significantly change over time. The mean Marx score of subjects who received allografts decreased significantly ( P < .01). Conclusions After early recognition, allograft use in young active patients was a risk factor for retear; graft choice by surgeons changed in the late period to use of allografts in older and less‐active patients, which correlated with a significant decrease in retear risk. Level of Evidence Level III, case control study.

Background: Anterior cruciate ligament reconstruction (ACLR) using a hamstring tendon autograft often results in hamstring muscle strength asymmetry. However, the effect of hamstring muscle strength asymmetry on knee mechanics has not been reported. Hypothesis: Participants with hamstring strength asymmetry would demonstrate altered involved limb knee mechanics during walking and jogging compared with those with more symmetric hamstring strength at least 2 years after ACLR with a hamstring tendon autograft. Study Design: Controlled laboratory study. Methods: There were a total of 45 participants at least 2 years after ACLR (22 male, 23 female; mean time after ACLR, 34.6 months). A limb symmetry index (LSI) was calculated for isometric hamstring strength to subdivide the sample into symmetric hamstring (SH) (LSI ≥90%; n = 18) and asymmetric hamstring (AH) (LSI <85%; n = 18) groups. Involved knee kinematic and kinetic data were collected using 3-dimensional motion analysis during gait and jogging. Peak sagittal-, frontal-, and transverse-plane knee angles and sagittal-plane knee moments and knee powers were calculated. Independent-samples t tests and analyses of covariance were used to compare involved knee kinematic and kinetic variables between the groups. Results: There were no differences in sagittal- and frontal-plane knee angles between the groups ( P > .05 for all). The AH group demonstrated decreased tibial internal rotation during weight acceptance during gait ( P = .01) and increased tibial external rotation during jogging at initial contact ( P = .03) and during weight acceptance ( P = .02) compared with the SH group. In addition, the AH group demonstrated decreased peak negative knee power during midstance ( P = .01) during gait compared with the SH group, after controlling for gait speed, which differed between groups. Conclusion: Participants with hamstring strength asymmetry showed altered involved knee mechanics in the sagittal plane during gait and in the transverse plane during gait and jogging compared with those with more symmetric hamstring strength. Clinical Relevance: Hamstring strength asymmetry is common at 3 years after ACLR with a hamstring tendon autograft and affects involved knee mechanics during gait and jogging. Additional research is warranted to further investigate the longitudinal effect of these alterations on knee function and joint health after ACLR.

Background: Knee laxity in the setting of suspected anterior cruciate ligament (ACL) injury is frequently assessed through physical examination using the Lachman, pivot-shift, and anterior drawer tests. The degree of laxity noted on these examinations may influence treatment decisions and prognosis. Hypothesis: Increased preoperative knee laxity would be associated with increased risk of subsequent revision ACL reconstruction and worse patient-reported outcomes 2 years postoperatively. Study Design: Cohort study; Level of evidence, 2. Methods: From an ongoing prospective cohort study, 2333 patients who underwent primary isolated ACL reconstruction without collateral or posterior cruciate ligament injury were identified. Patients reported by the operating surgeons as having an International Knee Documentation Committee (IKDC) grade D for Lachman, anterior drawer, or pivot-shift examination were classified as having high-grade laxity. Multiple logistic regression modeling was used to evaluate whether having high-grade preoperative laxity was associated with increased odds of undergoing revision ACL reconstruction within 2 years of the index procedure, controlling for patient age, sex, Marx activity level, level of competition, and graft type. Multiple linear regression modeling was used to evaluate whether having high-grade preoperative laxity was associated with worse IKDC score or Knee injury and Osteoarthritis Outcome Score Knee-Related Quality of Life subscale (KOOS-QOL) scores at a minimum 2 years postoperatively, controlling for baseline score, patient age, ethnicity, sex, body mass index, marital status, smoking status, sport participation, competition level, Marx activity rating score, graft type, and articular cartilage and meniscus status. Results: Pre-reconstruction laxity data were available for 2325 patients (99.7%). Two-year revision data were available for 2259 patients (96.8%), and patient-reported outcomes were available for 1979 patients (84.8%). High-grade preoperative laxity was noted in 743 patients (31.9%). The mean postoperative IKDC score was 81.8 ± 15.9, and the mean KOOS-QOL score was 72.0 ± 22.0. The presence of high-grade pre-reconstruction laxity was associated with significantly increased odds of ACL graft revision (odds ratio [OR] = 1.87 [95% CI, 1.19-2.95]; P = .007). The presence of high-grade pre-reconstruction laxity was not associated with any difference in postoperative IKDC (β = −0.56, P = .44) or KOOS-QOL (β = 0.04, P = .97). Conclusion: The presence of high-grade pre-reconstruction knee laxity as assessed by manual physical examination under anesthesia is associated with significantly increased odds of revision ACL surgery but has no association with patient-reported outcome scores at 2 years after ACL reconstruction.