Meniscal and Articular Cartilage Predictors of Outcome After Revision ACL Reconstruction: A 6-Year Follow-up Cohort Study.

BACKGROUND: Meniscal and chondral damage is common in the patient undergoing revision anterior cruciate ligament (ACL) reconstruction. PURPOSE: To determine if meniscal and/or articular cartilage pathology at the time of revision ACL surgery significantly influences a patient's outcome at 6-year follow-up. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: Patients undergoing revision ACL reconstruction were prospectively enrolled between 2006 and 2011. Data collection included baseline demographics, surgical technique, pathology, treatment, and scores from 4 validated patient-reported outcome instruments: International Knee Documentation Committee (IKDC), Knee injury and Osteoarthritis Outcome Score (KOOS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and Marx Activity Rating Scale. Patients were followed up at 6 years and asked to complete the identical set of outcome instruments. Regression analysis assessed the meniscal and articular cartilage pathology risk factors for clinical outcomes 6 years after revision ACL reconstruction. RESULTS: An overall 1234 patients were enrolled (716 males, 58%; median age, 26 years). Surgeons reported the pathology at the time of revision surgery in the medial meniscus (45%), lateral meniscus (36%), medial femoral condyle (43%), lateral femoral condyle (29%), medial tibial plateau (11%), lateral tibial plateau (17%), patella (30%), and trochlea (21%). Six-year follow-up was obtained on 79% of the sample (980/1234). Meniscal pathology and articular cartilage pathology (medial femoral condyle, lateral femoral condyle, lateral tibial plateau, trochlea, and patella) were significant drivers of poorer patient-reported outcomes at 6 years (IKDC, KOOS, WOMAC, and Marx). The most consistent factors driving outcomes were having a medial meniscal excision (either before or at the time of revision surgery) and patellofemoral articular cartilage pathology. Six-year Marx activity levels were negatively affected by having either a repair/excision of the medial meniscus (odds ratio range, 1.45-1.72; P≤ .04) or grade 3-4 patellar chondrosis (odds ratio, 1.72; P = .04). Meniscal pathology occurring before the index revision surgery negatively affected scores on all KOOS subscales except for sports/recreation (P < .05). Articular cartilage pathology significantly impaired all KOOS subscale scores (P < .05). Lower baseline outcome scores, higher body mass index, being a smoker, and incurring subsequent surgery all significantly increased the odds of reporting poorer clinical outcomes at 6 years. CONCLUSION: Meniscal and chondral pathology at the time of revision ACL reconstruction has continued significant detrimental effects on patient-reported outcomes at 6 years after revision surgery.

Descriptive Characteristics and Outcomes of Patients Undergoing Revision Anterior Cruciate Ligament Reconstruction With and Without Tunnel Bone Grafting.

BACKGROUND: Lytic or malpositioned tunnels may require bone grafting during revision anterior cruciate ligament reconstruction (rACLR) surgery. Patient characteristics and effects of grafting on outcomes after rACLR are not well described. PURPOSE: To describe preoperative characteristics, intraoperative findings, and 2-year outcomes for patients with rACLR undergoing bone grafting procedures compared with patients with rACLR without grafting. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: A total of 1234 patients who underwent rACLR were prospectively enrolled between 2006 and 2011. Baseline revision and 2-year characteristics, surgical technique, pathology, treatment, and patient-reported outcome instruments (International Knee Documentation Committee [IKDC], Knee injury and Osteoarthritis Outcome Score [KOOS], Western Ontario and McMaster Universities Osteoarthritis Index, and Marx Activity Rating Scale [Marx]) were collected, as well as subsequent surgery information, if applicable. The chi-square and analysis of variance tests were used to compare group characteristics. RESULTS: A total of 159 patients (13%) underwent tunnel grafting-64 (5%) patients underwent 1-stage and 95 (8%) underwent 2-stage grafting. Grafting was isolated to the femur in 31 (2.5%) patients, the tibia in 40 (3%) patients, and combined in 88 patients (7%). Baseline KOOS Quality of Life (QoL) and Marx activity scores were significantly lower in the 2-stage group compared with the no bone grafting group (P≤ .001). Patients who required 2-stage grafting had more previous ACLRs (P < .001) and were less likely to have received a bone-patellar tendon-bone or a soft tissue autograft at primary ACLR procedure (P≤ .021) compared with the no bone grafting group. For current rACLR, patients undergoing either 1-stage or 2-stage bone grafting were more likely to receive a bone-patellar tendon-bone allograft (P≤ .008) and less likely to receive a soft tissue autograft (P≤ .003) compared with the no bone grafting group. At 2-year follow-up of 1052 (85%) patients, we found inferior outcomes in the 2-stage bone grafting group (IKDC score = 68; KOOS QoL score = 44; KOOS Sport/Recreation score = 65; and Marx activity score = 3) compared with the no bone grafting group (IKDC score = 77; KOOS QoL score = 63; KOOS Sport/Recreation score = 75; and Marx activity score = 7) (P≤ .01). The 1-stage bone graft group did not significantly differ compared with the no bone grafting group. CONCLUSION: Tunnel bone grafting was performed in 13% of our rACLR cohort, with 8% undergoing 2-stage surgery. Patients treated with 2-stage grafting had inferior baseline and 2-year patient-reported outcomes and activity levels compared with patients not undergoing bone grafting. Patients treated with 1-stage grafting had similar baseline and 2-year patient-reported outcomes and activity levels compared with patients not undergoing bone grafting.

Returning to Activity After Anterior Cruciate Ligament Revision Surgery: An Analysis of the Multicenter Anterior Cruciate Ligament Revision Study (MARS) Cohort at 2 Years Postoperative.

BACKGROUND: Patients with anterior cruciate ligament (ACL) revision report lower outcome scores on validated knee questionnaires postoperatively compared to cohorts with primary ACL reconstruction. In a previously active population, it is unclear if patient-reported outcomes (PROs) are associated with a return to activity (RTA) or vary by sports participation level (higher level vs. recreational athletes). HYPOTHESES: Individual RTA would be associated with improved outcomes (ie, decreased knee symptoms, pain, function) as measured using validated PROs. Recreational participants would report lower PROs compared with higher level athletes and be less likely to RTA. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: There were 862 patients who underwent a revision ACL reconstruction (rACLR) and self-reported physical activity at any level preoperatively. Those who did not RTA reported no activity 2 years after revision. Baseline data included patient characteristics, surgical history and characteristics, and PROs: International Knee Documentation Committee questionnaire, Marx Activity Rating Scale, Knee injury and Osteoarthritis Outcome Score, and the Western Ontario and McMaster Universities Osteoarthritis Index. A binary indicator was used to identify patients with same/better PROs versus worse outcomes compared with baseline, quantifying the magnitude of change in each direction, respectively. Multivariable regression models were used to evaluate risk factors for not returning to activity, the association of 2-year PROs after rACLR surgery by RTA status, and whether each PRO and RTA status differed by participation level. RESULTS: At 2 years postoperatively, approximately 15% did not RTA, with current smokers (adjusted odds ratio [aOR] = 3.3; P = .001), female patients (aOR = 2.9; P < .001), recreational participants (aOR = 2.0; P = .016), and those with a previous medial meniscal excision (aOR = 1.9; P = .013) having higher odds of not returning. In multivariate models, not returning to activity was significantly associated with having worse PROs at 2 years; however, no clinically meaningful differences in PROs at 2 years were seen between participation levels. CONCLUSION: Recreational-level participants were twice as likely to not RTA compared with those participating at higher levels. Within a previously active cohort, no RTA was a significant predictor of lower PROs after rACLR. However, among patients who did RTA after rACLR, approximately 20% reported lower outcome scores. Most patients with rACLR who were active at baseline improved over time; however, patients who reported worse outcomes at 2 years had a clinically meaningful decline across all PROs.

Isolated Arthroscopic Partial Meniscectomy Is More Effective at Improving Meniscal Symptoms in Comparison With Mechanical Symptoms in Patients With Concomitant Untreated Chondral Lesions.

PURPOSE: To rank Knee Injury and Osteoarthritis Outcome Score (KOOS) questions from most to least improvement after arthroscopic partial meniscectomy (APM) and compare improvement of meniscal versus mechanical symptoms. METHODS: A secondary analysis of the Chondral Lesions and Meniscus Procedures (ChAMP) Trial was performed. Inclusion criteria were age 30 years or older with degenerative meniscal tear failing nonoperative management, with or without associated unstable chondral lesions. No chondral debridement was performed. Responses to the 42 KOOS questions ranged from 0 (extreme problems) to 4 (no problems), and were answered preoperatively and at 1 year after isolated APM. The 1-year mean change, or delta (Δ), was calculated for each KOOS question and the Δ for meniscal and mechanical symptoms were statistically compared. RESULTS: Greatest improvement in 135 eligible patients was observed for questions about (1) awareness of knee problems (Δ = 1.93, standard deviation [SD] = 1.38), (2) frequency of knee pain (Δ = 1.93, SD = 1.29), (3) degree of difficulty while twisting/pivoting on the injured knee (Δ = 1.88, SD = 1.13), (4) degree of difficulty while running (Δ = 1.67, SD = 1.30), and (5) being troubled by lack of confidence in the knee (Δ = 21.67, SD = 1.11). Least improvement was observed for questions about: (1) degree of difficulty while getting on/off the toilet (Δ = 0.94, SD = 0.96), (2) feel grinding or hear clicking when the knee moves (Δ= 0.90, SD = 1.25), 3) degree of difficulty while getting in/out of the bath (Δ= 0.88, SD = 1.00), (4) knee catches/hangs up during movement (Δ= 0.80, SD = 1.09), and (5) the ability to straighten the knee fully (Δ= 0.54, 1.44). There was greater improvement for the KOOS questions pertaining to meniscal versus mechanical symptoms (P < .00001). CONCLUSIONS: KOOS symptoms as reported by subjects' responses to the questions pertaining to the frequency of knee pain, twisting/pivoting, running, squatting, and jumping showed the most improvement 1 year after isolated APM, whereas those relating to mechanical symptoms improved the least. Focusing on meniscal rather than mechanical symptoms may help surgeons better identify patients expected to benefit from APM. LEVEL OF EVIDENCE: IV, retrospective analysis of prospectively collected data.

Better Outcomes but No Difference in Joint Space Narrowing at Five Years Among Patients Without Unstable Chondral Lesions Versus Those With Unstable Chondral Lesions (Left In Situ) at the Time of Arthroscopic Partial Meniscectomy.

PURPOSE: To compare 5-year outcomes among patients with and without unstable chondral lesions undergoing arthroscopic partial meniscectomy (APM). METHODS: Using data from the Chondral Lesions And Meniscal Procedures (ChAMP) Trial, we compared outcomes for patients with unstable chondral lesions found at the time of APM and left in situ (CL-noDeb, N = 71) versus patients without unstable chondral lesions (NoCL, N = 47) at 5 years after APM. Outcomes included the Western Ontario and McMaster Universities Arthritis Index (WOMAC), Knee Injury and Osteoarthritis Outcome Score (KOOS), visual analog pain scale, Short-form Health Survey (SF-36), physical knee measurements, progressive joint space narrowing on radiographs, and the rate of additional knee surgery. Multivariate linear regression was used to obtain mean differences (MDs) with corresponding 95% confidence intervals (CIs) adjusted for age, body mass index, and preoperative score (for postoperative scores). RESULTS: Compared with CL-noDeb, NoCL subjects had significantly greater improvement at 5 years in the KOOS score for function in sport and recreation (MD = 9.9 [95% CI, 0.7-19.1]), SF-36 pain (MD = 13.9 [95% CI, 5.5-22.3]), knee extension (MD = 0.8 [95% CI, 0.1-1.5]), and decreased quadriceps circumference at the mid-portion of the patella (MD = -1.5 [95% CI, -2.7 to -0.3). A greater proportion of patients in the NoCL group achieved the MCID for all outcome scores except for the WOMAC pain score (89% CL-NoDeb vs 87% NoCL) and SF-36 general (29% CL-NoDeb vs 23% NoCL). There were no significant group differences in measures of progressive radiographic joint space narrowing in any compartments of the operative knee and no significant difference in the rate of additional knee surgery within 5 years of the initial APM. CONCLUSIONS: Patients undergoing APM without unstable chondral lesions had statistically significantly better outcomes than patients with unstable chondral lesions at 5 years after surgery; however, there were no group differences in progressive radiographic joint space narrowing. LEVEL OF EVIDENCE: Level II, prospective comparative study.

Association Between Graft Choice and 6-Year Outcomes of Revision Anterior Cruciate Ligament Reconstruction in the MARS Cohort.

BACKGROUND: Although graft choice may be limited in the revision setting based on previously used grafts, most surgeons believe that graft choice for anterior cruciate ligament (ACL) reconstruction is an important factor related to outcome. HYPOTHESIS: In the ACL revision setting, there would be no difference between autograft and allograft in rerupture rate and patient-reported outcomes (PROs) at 6-year follow-up. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: Patients who had revision surgery were identified and prospectively enrolled in this cohort study by 83 surgeons over 52 sites. Data collected included baseline characteristics, surgical technique and pathology, and a series of validated PRO measures. Patients were followed up at 6 years and asked to complete the identical set of PRO instruments. Incidence of additional surgery and reoperation because of graft failure were also recorded. Multivariable regression models were used to determine the predictors (risk factors) of PROs, graft rerupture, and reoperation at 6 years after revision surgery. RESULTS: A total of 1234 patients including 716 (58%) men were enrolled. A total of 325 (26%) underwent revision using a bone-patellar tendon-bone (BTB) autograft; 251 (20%), soft tissue autograft; 289 (23%), BTB allograft; 302 (25%), soft tissue allograft; and 67 (5%), other graft. Questionnaires and telephone follow-up for subsequent surgery information were obtained for 809 (66%) patients, while telephone follow-up was only obtained for an additional 128 patients for the total follow-up on 949 (77%) patients. Graft choice was a significant predictor of 6-year Marx Activity Rating Scale scores (P = .024). Specifically, patients who received a BTB autograft for revision reconstruction had higher activity levels than did patients who received a BTB allograft (odds ratio [OR], 1.92; 95% CI, 1.25-2.94). Graft rerupture was reported in 5.8% (55/949) of patients by their 6-year follow-up: 3.5% (16/455) of patients with autografts and 8.4% (37/441) of patients with allografts. Use of a BTB autograft for revision resulted in patients being 4.2 times less likely to sustain a subsequent graft rupture than if a BTB allograft were utilized (P = .011; 95% CI, 1.56-11.27). No significant differences were found in graft rerupture rates between BTB autograft and soft tissue autografts (P = .87) or between BTB autografts and soft tissue allografts (P = .36). Use of an autograft was found to be a significant predictor of having fewer reoperations within 6 years compared with using an allograft (P = .010; OR, 0.56; 95% CI, 0.36-0.87). CONCLUSION: BTB and soft tissue autografts had a decreased risk in graft rerupture compared with BTB allografts. BTB autografts were associated with higher activity level than were BTB allografts at 6 years after revision reconstruction. Surgeons and patients should consider this information when choosing a graft for revision ACL reconstruction.

Rate of infection following revision anterior cruciate ligament reconstruction and associated patient- and surgeon-dependent risk factors: Retrospective results from MOON and MARS data collected from 2002 to 2011.

Infection 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.

Meniscal Repair in the Setting of Revision Anterior Cruciate Ligament Reconstruction: Results From the MARS Cohort.

BACKGROUND: Meniscal preservation has been demonstrated to contribute to long-term knee health. This has been a successful intervention in patients with isolated tears and tears associated with anterior cruciate ligament (ACL) reconstruction. However, the results of meniscal repair in the setting of revision ACL reconstruction have not been documented. PURPOSE: To examine the prevalence and 2-year operative success rate of meniscal repairs in the revision ACL setting. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: All cases of revision ACL reconstruction with concomitant meniscal repair from a multicenter group between 2006 and 2011 were selected. Two-year follow-up was obtained by phone and email to determine whether any subsequent surgery had occurred to either knee since the initial revision ACL reconstruction. If so, operative reports were obtained, whenever possible, to verify the pathologic condition and subsequent treatment. RESULTS: In total, 218 patients (18%) from 1205 revision ACL reconstructions underwent concurrent meniscal repairs. There were 235 repairs performed: 153 medial, 48 lateral, and 17 medial and lateral. The majority of these repairs (n = 178; 76%) were performed with all-inside techniques. Two-year surgical follow-up was obtained on 90% (197/218) of the cohort. Overall, the meniscal repair failure rate was 8.6% (17/197) at 2 years. Of the 17 failures, 15 were medial (13 all-inside, 2 inside-out) and 2 were lateral (both all-inside). Four medial failures were treated in conjunction with a subsequent repeat revision ACL reconstruction. CONCLUSION: Meniscal repair in the revision ACL reconstruction setting does not have a high failure rate at 2-year follow-up. Failure rates for medial and lateral repairs were both <10% and consistent with success rates of primary ACL reconstruction meniscal repair. Medial tears underwent reoperation for failure at a significantly higher rate than lateral tears.

Predictors of Patient-Reported Outcomes at 2 Years After Revision Anterior Cruciate Ligament Reconstruction.

BACKGROUND: Patient-reported outcomes (PROs) are a valid measure of results after revision anterior cruciate ligament (ACL) reconstruction. Revision ACL reconstruction has been documented to have worse outcomes when compared with primary ACL reconstruction. Understanding positive and negative predictors of PROs will allow surgeons to modify and potentially improve outcome for patients. PURPOSE/HYPOTHESIS: The purpose was to describe PROs after revision ACL reconstruction and test the hypothesis that patient- and technique-specific variables are associated with these outcomes. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: Patients undergoing revision ACL reconstruction were identified and prospectively enrolled by 83 surgeons over 52 sites. Data included baseline demographics, surgical technique and pathology, and a series of validated PRO instruments: International Knee Documentation Committee (IKDC), Knee injury and Osteoarthritis Outcome Score (KOOS), Western Ontario and McMaster Universities Osteoarthritis Index, and Marx Activity Rating Scale. Patients were followed up at 2 years and asked to complete the identical set of outcome instruments. Multivariate regression models were used to control for a variety of demographic and surgical factors to determine the positive and negative predictors of PRO scores at 2 years after revision surgery. RESULTS: A total of 1205 patients met the inclusion criteria and were successfully enrolled: 697 (58%) were male, with a median cohort age of 26 years. The median time since their most recent previous ACL reconstruction was 3.4 years. Two-year questionnaire follow-up was obtained from 989 patients (82%). The most significant positive predictors of 2-year IKDC scores were a high baseline IKDC score, high baseline Marx activity level, male sex, and having a longer time since the most recent previous ACL reconstruction, while negative predictors included having a lateral meniscectomy before the revision ACL reconstruction or having grade 3/4 chondrosis in either the trochlear groove or the medial tibial plateau at the time of the revision surgery. For KOOS, having a high baseline score and having a longer time between the most recent previous ACL reconstruction and revision surgery were significant positive predictors for having a better (ie, higher) 2-year KOOS, while having a lateral meniscectomy before the revision ACL reconstruction was a consistent predictor for having a significantly worse (ie, lower) 2-year KOOS. Statistically significant positive predictors for 2-year Marx activity levels included higher baseline Marx activity levels, younger age, male sex, and being a nonsmoker. Negative 2-year activity level predictors included having an allograft or a biologic enhancement at the time of revision surgery. CONCLUSION: PROs after revision ACL reconstruction are associated with a variety of patient- and surgeon-related variables. Understanding positive and negative predictors of PROs will allow surgeons to guide patient expectations as well as potentially improve outcomes.

Relationship Between Sports Participation After Revision Anterior Cruciate Ligament Reconstruction and 2-Year Patient-Reported Outcome Measures.

BACKGROUND: Anterior cruciate ligament (ACL) revision cohorts continually report lower outcome scores on validated knee questionnaires than primary ACL cohorts at similar time points after surgery. It is unclear how these outcomes are associated with physical activity after physician clearance for return to recreational or competitive sports after ACL revision surgery. HYPOTHESES: Participants who return to either multiple sports or a singular sport after revision ACL surgery will report decreased knee symptoms, increased activity level, and improved knee function as measured by validated patient-reported outcome measures (PROMs) and compared with no sports participation. Multisport participation as compared with singular sport participation will result in similar increased PROMs and activity level. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: A total of 1205 patients who underwent revision ACL reconstruction were enrolled by 83 surgeons at 52 clinical sites. At the time of revision, baseline data collected included the following: demographics, surgical characteristics, previous knee treatment and PROMs, the International Knee Documentation Committee (IKDC) questionnaire, Marx activity score, Knee injury and Osteoarthritis Outcome Score (KOOS), and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). A series of multivariate regression models were used to evaluate the association of IKDC, KOOS, WOMAC, and Marx Activity Rating Scale scores at 2 years after revision surgery by sports participation category, controlling for known significant covariates. RESULTS: Two-year follow-up was obtained on 82% (986 of 1205) of the original cohort. Patients who reported not participating in sports after revision surgery had lower median PROMs both at baseline and at 2 years as compared with patients who participated in either a single sport or multiple sports. Significant differences were found in the change of scores among groups on the IKDC (P < .0001), KOOS-Symptoms (P = .01), KOOS-Sports and Recreation (P = .04), and KOOS-Quality of Life (P < .0001). Patients with no sports participation were 2.0 to 5.7 times more likely than multiple-sport participants to report significantly lower PROMs, depending on the specific outcome measure assessed, and 1.8 to 3.8 times more likely than single-sport participants (except for WOMAC-Stiffness, P = .18), after controlling for known covariates. CONCLUSION: Participation in either a single sport or multiple sports in the 2 years after ACL revision surgery was found to be significantly associated with higher PROMs across multiple validated self-reported assessment tools. During follow-up appointments, surgeons should continue to expect that patients who report returning to physical activity after surgery will self-report better functional outcomes, regardless of baseline activity levels.

Association Between Bone Marrow Lesions, Chondral Lesions, and Pain in Patients Without Radiographic Evidence of Degenerative Joint Disease Who Underwent Arthroscopic Partial Meniscectomy.

Background: Bone marrow lesions (BMLs) have been found on magnetic resonance imaging in patients with meniscal tears. Purpose: We sought to determine the prevalence and location of BMLs, the association between BMLs and chondral lesions, and the association between BMLs and pain in patients without radiographic evidence of degenerative joint disease who underwent arthroscopic partial meniscectomy (APM). Study Design: Cohort study; Level of evidence, 2. Methods: We performed a secondary analysis of the Chondral Lesions And Meniscus Procedures (ChAMP) randomized controlled trial. BMLs were assessed on preoperative magnetic resonance imaging, and chondral lesions were documented at the time of surgery. Pain was assessed preoperatively and at 1 year after APM using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and the Knee injury and Osteoarthritis Outcome Score (KOOS). The chi-square test was used to examine the association between BMLs and chondral lesions, and the F test was used to examine the association between BMLs and pain. Results: Of 241 patients, 58.9% had ≥1 BMLs, and most were located on the medial tibial plateau (MTP; 74.6%) and/or medial femoral condyle (MFC; 28.9%). Most MTP BMLs were submeniscal (56%), and most MFC BMLs extended beyond the meniscus (73%). There were more MFC chondral lesions for patients with any MFC BMLs (P = .01) and submeniscal MFC BMLs (P = .02) versus those without BMLs, and there was no association between BMLs and chondral lesions on the MTP. There was also no association between BMLs and preoperative or postoperative pain scores. Conclusion: In patients without radiographic evidence of degenerative joint disease who underwent APM, BMLs were found in 58.9% of knees and were primarily located in the medial compartment. There was a borderline statistically significant association between BMLs and chondral lesions for the MFC; however, BMLs were not associated with pain scores preoperatively or at 1 year after surgery.

Physiologic Preoperative Knee Hyperextension Is a Predictor of Failure in an Anterior Cruciate Ligament Revision Cohort: A Report From the MARS Group.

BACKGROUND: The occurrence of physiologic knee hyperextension (HE) in the revision anterior cruciate ligament reconstruction (ACLR) population and its effect on outcomes have yet to be reported. Hypothesis/Purpose: The prevalence of knee HE in revision ACLR and its effect on 2-year outcome were studied with the hypothesis that preoperative physiologic knee HE ≥5° is a risk factor for anterior cruciate ligament (ACL) graft rupture. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: Patients undergoing revision ACLR were identified and prospectively enrolled between 2006 and 2011. Study inclusion criteria were patients undergoing single-bundle graft reconstructions. Patients were followed up at 2 years and asked to complete an identical set of outcome instruments (International Knee Documentation Committee, Knee injury and Osteoarthritis Outcome Score, WOMAC, and Marx Activity Rating Scale) as well as provide information regarding revision ACL graft failure. A regression model with graft failure as the dependent variable included age, sex, graft type at the time of the revision ACL surgery, and physiologic preoperative passive HE ≥5° (yes/no) to assess these as potential risk factors for clinical outcomes 2 years after revision ACLR. RESULTS: Analyses included 1145 patients, for whom 2-year follow-up was attained for 91%. The median age was 26 years, with age being a continuous variable. Those below the median were grouped as "younger" and those above as "older" (age: interquartile range = 20, 35 years), and 42% of patients were female. There were 50% autografts, 48% allografts, and 2% that had a combination of autograft plus allograft. Passive knee HE ≥5° was present in 374 (33%) patients in the revision cohort, with 52% being female. Graft rupture at 2-year follow-up occurred in 34 cases in the entire cohort, of which 12 were in the HE ≥5° group (3.2% failure rate) and 22 in the non-HE group (2.9% failure rate). The median age of patients who failed was 19 years, as opposed to 26 years for those with intact grafts. Three variables in the regression model were significant predictors of graft failure: younger age (odds ratio [OR] = 3.6; 95% CI, 1.6-7.9; P = .002), use of allograft (OR = 3.3; 95% CI, 1.5-7.4; P = .003), and HE ≥5° (OR = 2.12; 95% CI, 1.1-4.7; P = .03). CONCLUSION: This study revealed that preoperative physiologic passive knee HE ≥5° is present in one-third of patients who undergo revision ACLR. HE ≥5° was an independent significant predictor of graft failure after revision ACLR with a >2-fold OR of subsequent graft rupture in revision ACL surgery. Registration: NCT00625885 ( ClinicalTrials.gov identifier).

How Does the Presence of Unstable Chondral Lesions Affect Patient Outcomes After Partial Meniscectomy? The ChAMP Randomized Controlled Trial.

BACKGROUND: Chondral lesions are commonly encountered during arthroscopic partial meniscectomy (APM); however, it is unknown how these lesions affect postoperative outcomes. PURPOSE: The authors compared postoperative outcomes among patients with and without unstable chondral lesions 1 year after APM. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: The authors conducted a secondary analysis of data from the ChAMP (Chondral Lesions and Meniscus Procedures) randomized controlled trial. They compared the following outcomes for patients with unstable chondral lesions that were left in situ and observed (CL-noDeb) versus patients without unstable chondral lesions (NoCL) at 1 year after APM: Western Ontario and McMaster Universities Osteoarthritis Index, Knee injury and Osteoarthritis Outcome Score, visual analog scale for pain, the Short Form Health Survey, range of motion, quadriceps circumference, and effusion. Multivariate linear regression was used to obtain mean differences (MDs) with corresponding 95% CIs adjusted for age, body mass index, and preoperative score (for postoperative scores). RESULTS: Compared with the CL-noDeb group, the NoCL group had greater improvement in Western Ontario and McMaster Universities Osteoarthritis Index for pain (MD, 7.9, 95% CI: 2.7-13.1), stiffness (MD, 9.1, 95% CI: 1.9-16.3), and physical function (MD, 4.6, 95% CI: 0.1-9.0) and Knee injury and Osteoarthritis Outcome Score for pain (MD, 8.4, 95% CI: 2.7-14.0), function in sport and recreation (MD, 11, 95% CI: 3.0-19.1), and quality of life (MD, 10.4, 95% CI: 2.3-18.5). The NoCL group was less likely than the CL-noDeb group to have an effusion ( P = .02) 1 year after surgery. CONCLUSION: Patients undergoing APM without unstable chondral lesions had better outcomes than patients with unstable chondral lesions.

Risk Factors and Predictors of Significant Chondral Surface Change From Primary to Revision Anterior Cruciate Ligament Reconstruction: A MOON and MARS Cohort Study.

BACKGROUND: Articular cartilage health is an important issue following anterior cruciate ligament (ACL) injury and primary ACL reconstruction. Factors present at the time of primary ACL reconstruction may influence the subsequent progression of articular cartilage damage. HYPOTHESIS: Larger meniscus resection at primary ACL reconstruction, increased patient age, and increased body mass index (BMI) are associated with increased odds of worsened articular cartilage damage at the time of revision ACL reconstruction. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: Subjects who had primary and revision data in the databases of the Multicenter Orthopaedics Outcomes Network (MOON) and Multicenter ACL Revision Study (MARS) were included. Reviewed data included chondral surface status at the time of primary and revision surgery, meniscus status at the time of primary reconstruction, primary reconstruction graft type, time from primary to revision ACL surgery, as well as demographics and Marx activity score at the time of revision. Significant progression of articular cartilage damage was defined in each compartment according to progression on the modified Outerbridge scale (increase ≥1 grade) or >25% enlargement in any area of damage. Logistic regression identified predictors of significant chondral surface change in each compartment from primary to revision surgery. RESULTS: A total of 134 patients were included, with a median age of 19.5 years at revision surgery. Progression of articular cartilage damage was noted in 34 patients (25.4%) in the lateral compartment, 32 (23.9%) in the medial compartment, and 31 (23.1%) in the patellofemoral compartment. For the lateral compartment, patients who had >33% of the lateral meniscus excised at primary reconstruction had 16.9-times greater odds of progression of articular cartilage injury than those with an intact lateral meniscus ( P < .001). For the medial compartment, patients who had <33% of the medial meniscus excised at the time of the primary reconstruction had 4.8-times greater odds of progression of articular cartilage injury than those with an intact medial meniscus ( P = .02). Odds of significant chondral surface change increased by 5% in the lateral compartment and 6% in the medial compartment for each increased year of age ( P ≤ .02). For the patellofemoral compartment, the use of allograft in primary reconstruction was associated with a 15-fold increased odds of progression of articular cartilage damage relative to a patellar tendon autograft ( P < .001). Each 1-unit increase in BMI at the time of revision surgery was associated with a 10% increase in the odds of progression of articular cartilage damage ( P = .046) in the patellofemoral compartment. CONCLUSION: Excision of the medial and lateral meniscus at primary ACL reconstruction increases the odds of articular cartilage damage in the corresponding compartment at the time of revision ACL reconstruction. Increased age is a risk factor for deterioration of articular cartilage in both tibiofemoral compartments, while increased BMI and the use of allograft for primary ACL reconstruction are associated with an increased risk of progression in the patellofemoral compartment.

The Effect of Body Mass Index on Clinical Outcomes in Patients Without Radiographic Evidence of Degenerative Joint Disease After Arthroscopic Partial Meniscectomy.

PURPOSE: To examine the effect of obesity on clinical outcomes at 1 year after arthroscopic partial meniscectomy. METHODS: We conducted a secondary analysis of the ChAMP (Chondral Lesions and Meniscus Procedures) randomized controlled trial (N = 256). The visual analog scale for pain, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Knee Injury and Osteoarthritis Outcome Score (KOOS), range of motion, and presence of effusion were assessed preoperatively and at 1 year after arthroscopic partial meniscectomy. Body mass index was categorized as normal weight, 24.99 or less; overweight, 25 to 29.99; or obese, 30 or greater. Analysis of variance or the Cochran-Mantel-Haenszel test was used to examine differences in clinical outcomes between body mass index categories, and mean ± standard deviation or number (percentage) is reported. RESULTS: Preoperatively, obese patients had worse WOMAC pain (56.2 ± 17.2 vs 61.3 ± 17.2, P = .02), WOMAC physical function (55.8 ± 17.1 vs 62.8 ± 17.1, P = .004), pain visual analog scale (4.9 ± 2.1 vs 4.2 ± 1.9, P = .01), KOOS pain (49.5 ± 14.9 vs 54.0 ± 15.1, P = .02), and KOOS quality-of-life (27.9 ± 18.3 vs 36.9 ± 17.0, P = .001) scores, as well as decreased flexion (121.8° ± 22.6° vs 132.3° ± 16.5°, P = .003), compared with normal-weight patients. Overweight patients (n = 51 [51.5%], P = .03) and obese patients (n = 56 [52.8%], P = .002) were more likely to have knee effusion before surgery than normal-weight patients (n = 17 [34%]). At 1 year after surgery, overweight (130.2° ± 7.7°, P = .03) and obese (128.1° ± 7.1°, P = .003) patients had decreased flexion compared with normal-weight patients (134.5° ± 8.3°). CONCLUSIONS: Obese patients had worse pain, physical functioning, and quality-of-life scores, as well as decreased flexion, compared with normal-weight patients before arthroscopic partial meniscectomy. At 1 year after arthroscopic partial meniscectomy, there were no statistically significant differences in clinical outcomes but obesity was associated with decreased knee flexion. LEVEL OF EVIDENCE: Level II, prospective comparative trial.

Surgical Predictors of Clinical Outcomes After Revision Anterior Cruciate Ligament Reconstruction.

BACKGROUND: Revision anterior cruciate ligament (ACL) reconstruction has been documented to have worse outcomes compared with primary ACL reconstruction. HYPOTHESIS: Certain factors under the control of the surgeon at the time of revision surgery can both negatively and positively affect outcomes. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: Patients undergoing revision ACL reconstruction were identified and prospectively enrolled between 2006 and 2011. Data collected included baseline demographics, intraoperative surgical technique and joint disorders, and a series of validated patient-reported outcome instruments (International Knee Documentation Committee [IKDC] subjective form, Knee Injury and Osteoarthritis Outcome Score [KOOS], Western Ontario and McMaster Universities Osteoarthritis Index [WOMAC], and Marx activity rating scale) completed before surgery. Patients were followed up for 2 years and asked to complete an identical set of outcome instruments. Regression analysis was used to control for age, sex, body mass index (BMI), activity level, baseline outcome scores, revision number, time since last ACL reconstruction, and a variety of previous and current surgical variables to assess the surgical risk factors for clinical outcomes 2 years after revision ACL reconstruction. RESULTS: A total of 1205 patients (697 male [58%]) met the inclusion criteria and were successfully enrolled. The median age was 26 years, and the median time since their last ACL reconstruction was 3.4 years. Two-year follow-up was obtained on 82% (989/1205). Both previous and current surgical factors were found to be significant contributors toward poorer clinical outcomes at 2 years. Having undergone previous arthrotomy (nonarthroscopic open approach) for ACL reconstruction compared with the 1-incision technique resulted in significantly poorer outcomes for the 2-year IKDC ( P = .037; odds ratio [OR], 2.43; 95% CI, 1.05-5.88) and KOOS pain, sports/recreation, and quality of life (QOL) subscales ( P ≤ .05; OR range, 2.38-4.35; 95% CI, 1.03-10.00). The use of a metal interference screw for current femoral fixation resulted in significantly better outcomes for the 2-year KOOS symptoms, pain, and QOL subscales ( P ≤ .05; OR range, 1.70-1.96; 95% CI, 1.00-3.33) as well as WOMAC stiffness subscale ( P = .041; OR, 1.75; 95% CI, 1.02-3.03). Not performing notchplasty at revision significantly improved 2-year outcomes for the IKDC ( P = .013; OR, 1.47; 95% CI, 1.08-1.99), KOOS activities of daily living (ADL) and QOL subscales ( P ≤ .04; OR range, 1.40-1.41; 95% CI, 1.03-1.93), and WOMAC stiffness and ADL subscales ( P ≤ .04; OR range, 1.41-1.49; 95% CI, 1.03-2.05). Factors before revision ACL reconstruction that increased the risk of poorer clinical outcomes at 2 years included lower baseline outcome scores, a lower Marx activity score at the time of revision, a higher BMI, female sex, and a shorter time since the patient's last ACL reconstruction. Prior femoral fixation, prior femoral tunnel aperture position, and knee flexion angle at the time of revision graft fixation were not found to affect 2-year outcomes in this revision cohort. CONCLUSION: There are certain surgical variables that the physician can control at the time of revision ACL reconstruction that can modify clinical outcomes at 2 years. Whenever possible, opting for an anteromedial portal or transtibial surgical exposure, choosing a metal interference screw for femoral fixation, and not performing notchplasty are associated with significantly better 2-year clinical outcomes.

Patient Outcomes After Observation Versus Debridement of Unstable Chondral Lesions During Partial Meniscectomy: The Chondral Lesions And Meniscus Procedures (ChAMP) Randomized Controlled Trial.

BACKGROUND: It is unknown whether unstable chondral lesions observed during arthroscopic partial meniscectomy (APM) require treatment. We examined differences at 1 year with respect to knee pain and other outcomes between patients who had debridement (CL-Deb) and those who had observation (CL-noDeb) of unstable chondral lesions encountered during APM. METHODS: Patients who were ≥30 years old and undergoing APM were randomized to receive debridement (CL-Deb group; n = 98) or observation (CL-noDeb; n = 92) of unstable Outerbridge grade-II, III, or IV chondral lesions. Outcomes were evaluated preoperatively and at 8 to 12 days, 6 weeks, 3 months, 6 months, and 1 year postoperatively. Outcome measures included the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Knee Injury and Osteoarthritis Outcome Score (KOOS), visual analog scale (VAS) pain score, Short Form-36 (SF-36) health survey, range of motion, quadriceps circumference, and effusion. The primary outcome was the WOMAC pain score at 1 year. T tests were used to examine group differences in outcomes, and the means and standard deviations are reported. RESULTS: There were no significant differences between the groups with respect to any of the 1-year outcome scores. Compared with the CL-Deb group, the CL-noDeb group had improvement in the KOOS quality-of-life (p = 0.04) and SF-36 physical functioning scores (p = 0.01) as well as increased quadriceps circumference at 8 to 12 days (p = 0.02); had improvement in the pain score on the WOMAC (p = 0.02) and KOOS (p = 0.04) at 6 weeks; had improvement in SF-36 physical functioning scores at 3 months (p = 0.01); and had increased quadriceps circumference at 6 months (p = 0.02). CONCLUSIONS: Outcomes for the CL-Deb and CL-noDeb groups did not differ at 1 year postoperatively. This suggests that there is no benefit to arthroscopic debridement of unstable chondral lesions encountered during APM, and it is recommended that these lesions be left in situ. LEVEL OF EVIDENCE: Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Subsequent Surgery After Revision Anterior Cruciate Ligament Reconstruction: Rates and Risk Factors From a Multicenter Cohort.

BACKGROUND: While revision anterior cruciate ligament reconstruction (ACLR) can be performed to restore knee stability and improve patient activity levels, outcomes after this surgery are reported to be inferior to those after primary ACLR. Further reoperations after revision ACLR can have an even more profound effect on patient satisfaction and outcomes. However, there is a current lack of information regarding the rate and risk factors for subsequent surgery after revision ACLR. PURPOSE: To report the rate of reoperations, procedures performed, and risk factors for a reoperation 2 years after revision ACLR. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: A total of 1205 patients who underwent revision ACLR were enrolled in the Multicenter ACL Revision Study (MARS) between 2006 and 2011, composing the prospective cohort. Two-year questionnaire follow-up was obtained for 989 patients (82%), while telephone follow-up was obtained for 1112 patients (92%). If a patient reported having undergone subsequent surgery, operative reports detailing the subsequent procedure(s) were obtained and categorized. Multivariate regression analysis was performed to determine independent risk factors for a reoperation. RESULTS: Of the 1112 patients included in the analysis, 122 patients (11%) underwent a total of 172 subsequent procedures on the ipsilateral knee at 2-year follow-up. Of the reoperations, 27% were meniscal procedures (69% meniscectomy, 26% repair), 19% were subsequent revision ACLR, 17% were cartilage procedures (61% chondroplasty, 17% microfracture, 13% mosaicplasty), 11% were hardware removal, and 9% were procedures for arthrofibrosis. Multivariate analysis revealed that patients aged <20 years had twice the odds of patients aged 20 to 29 years to undergo a reoperation. The use of an allograft at the time of revision ACLR (odds ratio [OR], 1.79; P = .007) was a significant predictor for reoperations at 2 years, while staged revision (bone grafting of tunnels before revision ACLR) (OR, 1.93; P = .052) did not reach significance. Patients with grade 4 cartilage damage seen during revision ACLR were 78% less likely to undergo subsequent operations within 2 years. Sex, body mass index, smoking history, Marx activity score, technique for femoral tunnel placement, and meniscal tearing or meniscal treatment at the time of revision ACLR showed no significant effect on the reoperation rate. CONCLUSION: There was a significant reoperation rate after revision ACLR at 2 years (11%), with meniscal procedures most commonly involved. Independent risk factors for subsequent surgery on the ipsilateral knee included age <20 years and the use of allograft tissue at the time of revision ACLR.

A Case-Control Study Comparing Bone Bruising and Intra-articular Injuries in Patients Undergoing Anterior Cruciate Ligament Reconstruction With and Without Medial Collateral Ligament Tears.

BACKGROUND: Concomitant injuries can occur in patients with combined anterior cruciate ligament (ACL) and medial collateral ligament (MCL) tears; however, no studies have compared these injuries in patients undergoing ACL reconstruction with an MCL tear to those with an intact MCL. PURPOSE: To compare bone bruising, meniscus tears, and chondral lesions in patients undergoing ACL reconstruction with an MCL tear (cases) to those with an intact MCL (controls). STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: Thirty-two cases and 352 controls were identified from a prospective registry. Bone bruising was confirmed on magnetic resonance imaging, and meniscus tears and chondral lesions were confirmed arthroscopically. Demographics and concomitant injuries were compared between cases and controls using exact chi-square tests. Multivariate logistic regression was used to calculate odds ratios (ORs) and 95% CIs adjusted for age, sex, body mass index, and mechanism and type of injury. RESULTS: Cases had significantly more contact injuries than controls (58.1% vs 21.3%, P < .0001). The prevalence and odds of bone bruising of the lateral tibial plateau (89.7% vs 84.6%; P = .59; OR, 3.53; 95% CI, 0.45-27.71), lateral femoral condyle (82.8% vs 72.8%; P = .28; OR, 1.94; 95% CI, 0.64-5.88), medial tibial plateau (20.7% vs 31.7%; P = 0.29; OR, 0.53; 95% CI, 0.19-1.53), and medial femoral condyle (6.9% vs 8.3%; P ≥ .999; OR, 1.07; 95% CI, 0.21-5.40) did not differ significantly between cases and controls. The prevalence and odds of lateral meniscus tears (53.3% vs 43%; P = .34; OR, 1.85; 95% CI, 0.76-4.52), medial meniscus tears (31.3% vs 33.5%; P = .85; OR, 0.90; 95% CI, 0.37-2.21), and chondral lesions (16% vs 10.8%; P = .50; OR, 0.70; 95% CI, 0.15-3.21) also did not significantly differ between cases and controls. CONCLUSION: ACL-MCL injuries were most often due to a contact mechanism, whereas ACL tears without associated MCL injury were more frequently due to a noncontact mechanism. However, there were no significant differences in concomitant injuries in ACL-MCL knees versus ACL knees.

How Accurate Are Patients at Diagnosing the Cause of Their Knee Pain With the Help of a Web-based Symptom Checker?

BACKGROUND: Researching medical information is the third most popular activity online, and there are a variety of web-based symptom checker programs available. PURPOSE: This study evaluated a patient's ability to self-diagnose their knee pain from a list of possible diagnoses supplied by an accurate symptom checker. STUDY DESIGN: Cohort study (diagnosis); Level of evidence, 2. METHODS: All patients older than 18 years who presented to the office of 7 different fellowship-trained sports medicine surgeons over an 8-month period with a complaint of knee pain were asked to participate. A web-based symptom checker for knee pain was used; the program has a reported accuracy of 89%. The symptom checker generates a list of potential diagnoses after patients enter symptoms and links each diagnosis to informative content. After exploring the informative content, patients selected all diagnoses they felt could explain their symptoms. Each patient was later examined by a physician who was blinded to the differential generated by the program as well as the patient-selected diagnoses. A blinded third party compared the diagnoses generated by the program with those selected by the patient as well as the diagnoses determined by the physician. The level of matching between the patient-selected diagnoses and the physician's diagnoses determined the patient's ability to correctly diagnose their knee pain. RESULTS: There were 163 male and 165 female patients, with a mean age of 48 years (range, 18-76 years). The program generated a mean 6.6 diagnoses (range, 2-15) per patient. Each patient had a mean 1.7 physician diagnoses (range, 1-4). Patients selected a mean 2 diagnoses (range, 1-9). The patient-selected diagnosis matched the physician's diagnosis 58% of the time. CONCLUSION: With the aid of an accurate symptom checker, patients were able to correctly identify the cause of their knee pain 58% of the time.