Tobramycin and Vancomycin in an In Vitro Model of Anterior Cruciate Ligament Allograft Decontamination.

BACKGROUND: Approximately 100,000 anterior cruciate ligament (ACL) reconstructions (ACLRs) occur annually in the United States, and postoperative surgical-site infection is a relatively rare but devastating complication, often leading to graft failure or septic arthritis of the knee, necessitating repeat surgery. Wrapping allografts in vancomycin-soaked gauze has been adopted as a common sterilization technique in the operating room to reduce surgical-site infection; however, identifying effective alternatives to vancomycin has not been extensively pursued. HYPOTHESIS: Tobramycin would be as effective as vancomycin in reducing the concentrations of Staphylococcus epidermidis bacteria on tendon allografts. STUDY DESIGN: Controlled laboratory study. METHODS: S. epidermidis strain ATCC 12228 was inoculated onto the human cadaveric gracilis tendon. The tendons were wrapped in sterile gauze saturated with tobramycin or vancomycin at various experimental concentrations. Bacteria remaining on the tendon were dislodged, serially diluted, and plated for colony counting. Statistical analysis was performed utilizing 2-way analysis of variance testing. Results were considered statistically significant when P < .05. RESULTS: Vancomycin (P = .0001) and tobramycin (P < .0001) reduced bacterial concentration. Tobramycin was found to produce a statistically significant reduction in bacterial concentration at concentrations as low as 0.1 mg/mL (P < .0001 and P = .01 at 10 and 20 minutes), while vancomycin produced a statistically significant reduction at a concentration as low as 2.5 mg/mL (P < .0001 at both 10 and 20 minutes). CONCLUSION: This study demonstrates that tobramycin is as effective as vancomycin in bacterial concentration reduction but can achieve this reduction level at lower doses. Further studies clarifying the biomechanical and cytotoxic effects of tobramycin on tendon tissue are indicated to solidify its use as a clinical alternative to vancomycin in ACLR. CLINICAL RELEVANCE: These results will begin establishing tobramycin as an alternative to vancomycin in ACL graft decontamination. Because of relatively frequent shortages of vancomycin, establishing tobramycin as an alternative agent is a useful option for the orthopaedic surgeon.

More Is Not Merrier: Increasing Numbers of All-Inside Implants Do Not Correlate with Higher Odds of Revision Surgery.

The purpose of this study was to evaluate the relationship between the number of all-inside meniscal repair implants placed and the risk of repair failure. We hypothesized that the use of higher numbers of all-inside meniscus repair implants would be associated with increased failure risk. A retrospective chart review identified 351 patients who underwent all-inside meniscus repair between 2006 and 2013 by a sports medicine fellowship-trained orthopaedic surgeon at a single institution. Patient demographics (age, body mass index [BMI], sex) and surgical data (number of implants used, concomitant anterior cruciate ligament reconstruction [cACLR], and tear type/size/location) were recorded. Patients who received repairs in both menisci or who had follow-up < 1-year postoperatively were excluded. Repair failure was identified through chart review or patient interviews defined as a revision surgery on the index knee such as partial meniscectomy, total knee arthroplasty, meniscus transplant, or repeat repair. Logistic regression modeling was utilized to evaluate the relationship between the number of implants used and repair failure. A total of 227 all-inside meniscus repairs were included with a mean follow-up of 5.0 ± 3.0 years following surgery. Repair failure was noted in 68 knees (30.3%)-in 28.1% of knees with fewer than four implants and in 35.8% of knees with four or more implants (p = 0.31). No significant increase in failure was observed with increasing number of all-inside medial (odds ratio [OR]: 1.15; 95% confidence interval [CI]: 0.79-1.7; p = 0.46) or lateral (OR: 0.86; 95% CI: 0.47-1.57; p = 0.63) implants after controlling for patient age, BMI, cACLR, tear type, or size. Tears of the lateral meniscus located in the red-white and white-white zones had lower odds of failure (OR: 0.14; 95% CI: 0.02-0.88; p = 0.036) than tears within the red-red zone, and patients with cACLR had lower odds of repair failure (OR: 0.40; 95% CI: 0.18-0.86, p = 0.024) than those without. The number of all-inside implants placed during meniscus tear repair did not affect the likelihood of repair failure leading to reoperation after controlling for BMI, age, tear type, size, location, and cACLR. LEVEL OF EVIDENCE: III.

Management of Patellar Tendinopathy.

Patellar tendinopathy is a common pathology typically seen in athletes involved in repetitive explosive jumping and running activities. Also known as jumpers' knee, it is commonly seen in high-level basketball players. Typically, athletes continue to play with symptoms, which can be aggravated and progress to partial patellar tendon tears. When partial patellar tendon tears occur, prolonged recovery and decreased performance is commonly seen. The pathology and treatment can be frustrating for both the athlete and medical provider. Patellar tendinopathy typically does not involve inflammation but rather microinjury to the tendon fibers, which leads to mucoid degeneration, necrosis, and loss of transitional fibrocartilage. When partial tendon tears do occur, the typical location is posteromedially adjacent to the patella. Treatment involves a stepwise approach starting with nonoperative means, including activity modification, nonsteroidal anti-inflammatories, and physical therapy focused on eccentrics. Extracorporeal shock wave treatments and injections with platelet-rich plasma or bone marrow aspirate concentrate should be considered, with evolving literature to support their use. Ultrasound percutaneous tendon scrapping with a needle supplemented with the aforementioned injections is an emerging treatment option that the authors have found to be helpful, although further studies are required. Surgical intervention is considered after failure of nonoperative treatments, and typically occurs in tears greater than 50% of the tendon thickness and in tendons with increased thickness (>8.8 mm). Open or arthroscopic debridement can be considered, with no studies showing superior outcomes with either technique; however, no high-quality comparison studies exist. The authors prefer an open technique where, much like a bone-patellar tendon-bone harvest, the unhealthy proximal tendon and bone are excised with then closure of the healthy tendon with absorbable sutures. Suture anchor repair may also be used when necessary. In a recent systematic review, surgical management of patellar tendinopathy has been shown to result in improved patient-reported outcomes with return to sport at high levels.1 Treatment for the difficult and sometimes frustrating pathology of patellar tendinopathy continues to evolve, with biologic and less-invasive ultrasound-based treatments showing promise, and surgical intervention providing reliable outcomes.

Predictors of Return to Activity at 2 Years After Anterior Cruciate Ligament Reconstruction Among Patients With High Preinjury Marx Activity Scores: A MOON Prospective Cohort Study.

BACKGROUND: Predictors of return to activity after anterior cruciate ligament reconstruction (ACLR) among patients with relatively high preinjury activity levels remain poorly understood. PURPOSE/HYPOTHESIS: The purpose of this study was to identify predictors of return to preinjury levels of activity after ACLR, defined as achieving a Marx activity score within 2 points of the preinjury value, among patients with Marx activity scores of 12 to 16 who had been prospectively enrolled in the Multicenter Orthopaedic Outcomes Network (MOON) cohort. We hypothesized that age, sex, preinjury activity level, meniscal injuries and/or procedures, and concurrent articular cartilage injuries would predict return to preinjury activity levels at 2 years after ACLR. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: All unilateral ACLR procedures from 2002 to 2008 performed in patients enrolled in the MOON, with preinjury Marx activity scores ranging from 12 to 16, were evaluated with a specific focus on return to preinjury activity levels at 2 years postoperatively. Return to activity was defined as a Marx activity score within 2 points of the preinjury value. The proportion of patients able to return to preinjury activity levels was calculated, and multivariable modeling was performed to identify risk factors for patients' inability to return to preinjury activity levels. RESULTS: A total of 1188 patients were included in the final analysis. The median preinjury Marx activity score was 16 (interquartile range, 12-16). Overall, 466 patients (39.2%) were able to return to preinjury levels of activity, and 722 patients (60.8%) were not able to return to preinjury levels of activity. Female sex, smoking at the time of ACLR, fewer years of education, lower 36-Item Short Form Health Survey Mental Component Summary scores, and higher preinjury Marx activity scores were predictive of patients' inability to return to preinjury activity levels. Graft type, revision ACLR, the presence of medial and/or lateral meniscal injuries, a history of meniscal surgery, the presence of articular cartilage injuries, a history of articular cartilage treatment, and the presence of high-grade knee laxity were not predictive of a patient's ability to return to preinjury activity level. CONCLUSION: At 2 years after ACLR, most patients with high preinjury Marx activity scores did not return to their preinjury level of activity. The higher the preinjury Marx activity score that a patient reported at the time of enrollment, the less likely he/she was able to return to preinjury activity level. Smoking and lower mental health at the time of ACLR were the only modifiable risk factors in this cohort that predicted an inability to return to preinjury activity levels. Continued effort and investigation are required to maximize functional recovery after ACLR in patients with high preinjury levels of activity.

Larger Prior Tibial Tunnel Size Is Associated with Increased Failure Risk following Revision Anterior Cruciate Ligament Reconstruction.

We hypothesize that larger prior tunnel size is associated with an increased risk of failure of single-stage revision anterior cruciate ligament reconstruction (ACLR) as defined by the performance of a re-revision (third) ACLR on the index knee. Retrospective review identified 244 patients who underwent single-stage revision ACLR at a single center with available preoperative radiographs. Patient and surgical factors were extracted by chart review. The maximum diameter of the tibial tunnel was measured on lateral radiographs and the maximum diameter of the femoral tunnel was measured on anteroposterior radiographs. Record review and follow-up phone calls were used to identify failure of the revision surgery as defined by re-revision ACLR on the index knee. One hundred and seventy-one patients (70%) were reviewed with a mean of 3.9 years follow-up. Overall, 23 patients (13.4%) underwent re-revision surgery. Mean tibial tunnel size was 12.6 ± 2.8 mm (range: 5.7-26.9 mm) and mean femoral tunnel size was 11.7 ± 2.8 mm (range: 6.0-23.0 mm). Re-revision risk increased with tibial tunnel size. Tibial tunnels 11 mm and under had a re-revision risk of 4.2%, while tunnels > 11 mm had a risk of 17.1% (relative risk: 4.1, p = 0.025). No significant association between femoral tunnel size and re-revision risk was noted. Patients with prior tibial tunnels > 11mm in diameter at revision surgery had significantly increased risk of re-revision ACLR. Further studies are needed to explore the relationship between prior tunnel size and outcomes of revision ACLR.

Influence of Staphylococcus epidermidis biofilm on the mechanical strength of soft tissue allograft.

We sought to determine the impact of bacterial inoculation and length of exposure on the mechanical integrity of soft tissue tendon grafts. Cultures of Staphylococcus epidermidis were inoculated on human tibialis posterior cadaveric tendon to grow biofilms. A low inoculum in 10% growth medium was incubated for 30 min to replicate conditions of clinical infection. Growth conditions assessed included inoculum concentrations of 100, 1000, 10,000 colony-forming units (CFUs). Tests using the MTS Bionix system were performed to assess the influence of bacterial biofilms on tendon strength. Load-to-failure testing was performed on the tendons, and the ultimate tensile strength was obtained from the maximal force and the cross-sectional area. Displacements of tendon origin to maximal displacement were normalized to tendon length to obtain strain values. Tendon force-displacement and stress-strain relationships were calculated, and Young's modulus was determined. Elastic modulus and ultimate tensile strength decreased with increasing bioburden. Young's modulus was greater in uninoculated controls compared to tendons inoculated at 10,000 CFU (p = 0.0011) but unaffected by bacterial concentrations of 100 and 1000 CFU (p = 0.054, p = 0.078). Increasing bioburden was associated with decreased peak load to failure (p = 0.043) but was most significant compared to the control under the 10,000 and 1000 CFU growth conditions (p = 0.0005, p = 0.049). The presence of S. epidermidis increased elasticity and decreased ultimate tensile stress of human cadaveric tendons, with increasing effect noted with increasing bioburden.

Association of Elevated Posterior Tibial Slope With Revision Anterior Cruciate Ligament Graft Failure in a Matched Cohort Analysis.

BACKGROUND: Elevated posterior tibial slope (PTS) has been identified as an important risk factor in anterior cruciate ligament (ACL) injuries and ACL graft failures. The cutoff value to recommend treatment with slope-reducing osteotomy remains unclear and is based on expert opinion and small case series. PURPOSE: (1) To determine whether there is a difference in PTS shown on lateral knee radiographs and magnetic resonance imaging (MRI) scans in a group of patients who experienced revision ACL graft failure versus a control group of patients who underwent successful revision ACL reconstruction, (2) to identify cutoff values of PTS measurements that predict risk of revision ACL graft failure, and (3) to examine whether there is a correlation between radiographic and MRI measurements of PTS. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: A total of 38 patients who experienced revision ACL graft failure were identified from a revision ACL database. These patients were matched 1:1 by age, sex, and graft type to a group of 38 control patients who underwent revision ACL reconstruction with no evidence of graft failure at a minimum 2 years of follow-up. Medial and lateral PTS were measured by lateral knee radiographs and MRI scans of the affected limb. Demographics, surgical characteristics, and PTS were compared between the groups. The optimal cutoff values of medial and lateral PTS per radiographs and MRI scans for predicting increased risk of revision ACL graft failure were determined by receiver operating characteristic curves. Conditional multivariable logistic regression was used to assess the relative contribution of PTS cutoff values as a predictor of revision graft failure. RESULTS: The mean PTS values in the failure group were significantly higher than those in the control group on radiographs (medial, 13.2°± 2.9° vs 10.3°± 2.9°; P < .001; lateral, 12.9°± 3.0° vs 9.8°± 2.8°; P < .001) and MRI scans (medial, 7.2°± 3.1° vs 4.8°± 2.9°; P < .001; lateral, 8.4 ± 3.1° vs 5.9 ± 3.0°; P < .001). A radiographic medial PTS ≥14° had the highest increased risk of revision ACL graft failure with sensitivity equal to 50% and specificity to 92.1% (odds ratio, 18.71; 95% CI, 2.0-174.9; P = .01). CONCLUSION: Elevated PTS was a significant risk factor for revision ACL graft failure. Patients with radiographic medial PTS ≥14° had 18.7-times increased risk of revision ACL failure.

Smaller Iatrogenic Defects Created by Inside-Out Compared With All-Inside Meniscus Repair Devices in Human Cadaveric Model.

PURPOSE: (1) To investigate the pattern and diameter of the iatrogenic defect that meniscal repair devices impose on meniscal tissue and (2) to determine whether repair-induced defect patterns or diameters differ across devices. METHODS: Sixty-one fresh frozen human cadaveric menisci were used (n = 9; eliminated). All-inside devices (n = 9) included ULTRA FAST-FIX, FAST-FIX 360, Depuy Mitek 0° and 12° TRUESPAN, ConMed Sequent, Zimmer Biomet JuggerStitch, Stryker IvyAIR, Arthrex FiberStitch and Meniscal Cinch II. Inside-out needles (n = 4) included ConMed HiFi, Depuy Mitek ORTHOCORD, Arthrex-2-0 FiberWire, and Stryker SharpShooter. Following India Ink staining, implant devices were inserted into cadaveric menisci. Samples were fixed in formalin solution and imaged with a high-resolution camera. Defects were classified by qualitative evaluation. Defect and needle diameter were quantified with software assistance. Statistical analysis was performed using analysis of variance testing. RESULTS: We analyzed 644 iatrogenic defects with mean defect diameter of 1.96 mm (standard deviation 0.86). For all-inside devices, defect patterns (n = 436) were 15.6% linear, 38.1% semilunar, 46.3% stellate, while inside-out devices (n = 208) were 95.7% stellate, 4.3% linear, and 0.0% semilunar. All-inside devices had mean defect diameter of 2.46 mm, while inside-out meniscus needles had mean 0.90 mm defect diameter (P < .001). FasT-FIX 360, ULTRA-FAST-FIX, and Arthrex Meniscal Cinch II induced smaller diameter defects than other all-inside devices (F = 20.2, P < .05). Strong positive correlation was found comparing outer needle diameter and mean defect diameters across all devices (R2 = 0.9447). CONCLUSIONS: Needles utilized in meniscal implant systems produce the following basic defect patterns: stellate (62.3%), semilunar (25.8%), and linear (11.9%). A strong positive correlation was found between mean defect size and outer needle diameter across all devices. Inside-out double-armed flexible needles produced significantly smaller defects than all-inside devices. Of the all-inside devices, ULTRA FAST-FIX, FAST-FIX 360, and Arthrex Meniscal Cinch II produced smaller defects on average. CLINICAL RELEVANCE: While the true clinical impact of these findings cannot be drawn from the present study, this investigation provides necessary context to better understand reported similarities and differences in healing rates and outcomes between inside-out and all-inside repair techniques.

Arthroscopic Bone Graft Technique for Two-Stage Revision Anterior Cruciate Ligament Reconstruction.

Revision anterior cruciate ligament reconstruction is an increasingly common procedure, with 2-stage surgery often required to address large bone defects and malpositioned tunnels. The arthroscopic bone grafting technique described herein uses morselized allograft bone to provide reproducible fill of asymmetrical bone defects without autograft harvest or additional loss of native bone. The second stage of the anterior cruciate ligament reconstruction can typically proceed 6 months following bone grafting.

Accelerated rehabilitation program following medial patellofemoral ligament reconstruction does not increase risk of recurrent instability.

BACKGROUND: Rehabilitation protocols following medial patellofemoral ligament (MPFL) reconstruction were historically restrictive, with patients often immobilized and/or given weightbearing restrictions. However, more recently published protocols have been more aggressive. We compared patient-reported outcomes and recurrent dislocation risk between patients treated with a restrictive rehabilitation program (early post-operative bracing and weightbearing restrictions) and an accelerated rehabilitation protocol (no post-operative bracing or weightbearing restrictions) following MPFL reconstruction. METHODS: Patients who underwent isolated MPFL reconstruction at an academic center between 2008 and 2016 were identified. Patient demographics, anatomical measurements, surgical details, and outcomes were collected. During this period, the rehabilitation protocol at the center transitioned from a restrictive to an accelerated rehabilitation protocol. Failure risk and patient-reported outcomes were compared based on rehabilitation protocol. RESULTS: Of the163 isolated MPFL reconstructions performed during the study period, 123 (75%) were available for minimum one-year follow up at a mean of 4.0 years post-operative. Overall, 53 knees (43%) underwent the accelerated rehabilitation protocol and the remaining 70 knees (57%) underwent the restrictive protocol. There were 3 recurrent dislocations during the study period (2.4%), all of which occurred in the restrictive rehabilitation group. Multiple linear regression demonstrated that being in the accelerated rehabilitation group was not associated with poorer Knee injury and Osteoarthritis Outcome Score (KOOS) subscales controlling for age, sex, body mass index, Caton-Deschamps Index, tibial tubercle-trochlear groove distance, sulcus angle, MPFL graft choice, and length of follow-up. CONCLUSION: An accelerated rehabilitation protocol without immobilization or weightbearing restrictions does not increase risk of recurrent patellar dislocation or poorer patient-reported outcome following isolated MPFL reconstruction.

Treatment of Chronic Proximal Hamstring Tendinopathy with Surgical Debridement and Suture Anchor Repair.

We evaluated outcomes following surgical debridement and suture anchor repair of chronic proximal hamstring tendinopathy without sciatic nerve decompression. Chart review identified eight patients (one bilateral) who met study requirements. All eight patients were available for follow-up at a mean of 6.7 years and none underwent re-operation on the index hip during the follow-up period. Seven patients completed patient-reported outcome scores. The mean LEFS score was 81.1, and the mean SANE score was 74.9. The mean Marx activity score was 2.8, and the mean Custom Marx score was 23.3. Pain relief was excellent. The mean numeric pain score at rest was 0.6, while the mean numeric pain score with activity was 4.0. Treatment of chronic, recalcitrant proximal hamstring tendinopathy with surgical debridement and suture anchor repair without exploration of the sciatic nerve results in excellent pain relief, good function, and low re-operation risk. (Journal of Surgical Orthopaedic Advances 31(1):061-064, 2022).

Treatment of post-meniscectomy knee symptoms with medial meniscus replacement results in greater pain reduction and functional improvement than non-surgical care.

PURPOSE: Partial meniscectomy is a common orthopedic procedure intended to improve knee pain and function in patients with irreparable meniscal tears. However, 6-25% of partial meniscectomy patients experience persistent knee pain after surgery. In this randomized controlled trial (RCT) involving subjects with knee pain following partial meniscectomy, it was hypothesized that treatment with a synthetic medial meniscus replacement (MMR) implant provides significantly greater improvements in knee pain and function compared to non-surgical care alone. METHODS: In this prospective, multicenter RCT, subjects with persistent knee pain following one or more previous partial meniscectomies were randomized to receive either MMR or non-surgical care. This analysis evaluated the 1-year outcomes of this 2-year clinical trial. Patient-reported knee pain, function, and quality of life were measured using nine separate patient-reported outcomes. The primary outcomes were the pain subscale of the Knee injury and Osteoarthritis Outcome Score (KOOS) and the average of all five KOOS subscales (KOOS Overall). Treatment cessation was defined as permanent device removal in the MMR group and any surgical procedure to the index knee in the non-surgical care group. RESULTS: Treated subjects had a median age of 52 years old (range 30-69 years) and one or more previous partial meniscectomies at a median of 34 months (range 5-430 months) before trial entry. Among 127 subjects treated with either MMR (n = 61) or non-surgical care (n = 66), 11 withdrew from the trial or were lost to follow-up (MMR, n = 0; non-surgical care, n = 11). The magnitude of improvement from baseline to 1 year was significantly greater in subjects who received MMR in both primary outcomes of KOOS Pain (P = 0.013) and KOOS Overall (P = 0.027). Treatment cessation was reported in 14.5% of non-surgical care subjects and only 4.9% of MMR subjects (n.s.). CONCLUSION: Treatment with the synthetic MMR implant resulted in significantly greater improvements in knee pain, function, and quality of life at 1 year of follow-up compared to treatment with non-surgical care alone. LEVEL OF EVIDENCE: I.

Anterior Cruciate Ligament Reconstruction With Concomitant Meniscal Repair: Is Graft Choice Predictive of Meniscal Repair Success?

BACKGROUND: When meniscal repair is performed during anterior cruciate ligament (ACL) reconstruction (ACLR), the effect of ACL graft type on meniscal repair outcomes is unclear. HYPOTHESIS: The authors hypothesized that meniscal repairs would fail at the lowest rate when concomitant ACLR was performed with bone--patellar tendon--bone (BTB) autograft. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: Patients who underwent meniscal repair at primary ACLR were identified from a longitudinal, prospective cohort. Meniscal repair failures, defined as any subsequent surgical procedure addressing the meniscus, were identified. A logistic regression model was built to assess the association of graft type, patient-specific factors, baseline Marx activity rating score, and meniscal repair location (medial or lateral) with repair failure at 6-year follow-up. RESULTS: A total of 646 patients were included. Grafts used included BTB autograft (55.7%), soft tissue autograft (33.9%), and various allografts (10.4%). We identified 101 patients (15.6%) with a documented meniscal repair failure. Failure occurred in 74 of 420 (17.6%) isolated medial meniscal repairs, 15 of 187 (8%) isolated lateral meniscal repairs, and 12 of 39 (30.7%) of combined medial and lateral meniscal repairs. Meniscal repair failure occurred in 13.9% of patients with BTB autografts, 17.4% of patients with soft tissue autografts, and 19.4% of patients with allografts. The odds of failure within 6 years of index surgery were increased more than 2-fold with allograft versus BTB autograft (odds ratio = 2.34 [95% confidence interval, 1.12-4.92]; P = .02). There was a trend toward increased meniscal repair failures with soft tissue versus BTB autografts (odds ratio = 1.41 [95% confidence interval, 0.87-2.30]; P = .17). The odds of failure were 68% higher with medial versus lateral repairs (P < .001). There was a significant relationship between baseline Marx activity level and the risk of subsequent meniscal repair failure; patients with either very low (0-1 points) or very high (15-16 points) baseline activity levels were at the highest risk (P = .004). CONCLUSION: Meniscal repair location (medial vs lateral) and baseline activity level were the main drivers of meniscal repair outcomes. Graft type was ranked third, demonstrating that meniscal repairs performed with allograft were 2.3 times more likely to fail compared with BTB autograft. There was no significant difference in failure rates between BTB versus soft tissue autografts. REGISTRATION: NCT00463099 (ClinicalTrials.gov identifier).

Neither Residual Anterior Knee Laxity Up to 6 mm nor a Pivot Glide Predict Patient-Reported Outcome Scores or Subsequent Knee Surgery Between 2 and 6 Years After ACL Reconstruction.

BACKGROUND: A primary goal of anterior cruciate ligament reconstruction (ACLR) is to reduce pathologically increased anterior and rotational laxity of the knee, but the effects of residual laxity on patient-reported outcomes (PROs) after ACLR remain unclear. HYPOTHESIS: Increased residual laxity at 2 years postoperatively is predictive of a higher risk of subsequent ipsilateral knee surgery and decreases in PRO scores from 2 to 6 years after surgery. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: From a prospective multicenter cohort, 433 patients aged <36 years were identified at a minimum 2 years after primary ACLR. These patients underwent a KT-1000 arthrometer assessment and pivot-shift test and completed PRO assessments with the Knee injury and Osteoarthritis Outcome Score and International Knee Documentation Committee (IKDC) scores. Patients completed the same PROs at 6 years postoperatively, and any subsequent ipsilateral knee procedures during this period were recorded. Subsequent surgery risk and change in PROs from 2 to 6 years postoperatively were compared based on residual side-to-side KT-1000 arthrometer differences (<-1 mm, -1 to 2 mm, 2 to 6 mm, and >6 mm) in laxity at 2 years postoperatively. Multiple linear regression models were built to determine the relationship between 2-year postoperative knee laxity and 2- to 6-year change in PROs while controlling for age, sex, body mass index, smoking status, meniscal and cartilage status, and graft type. RESULTS: A total of 381 patients (87.9%) were available for follow-up 6 years postoperatively. There were no significant differences in risk of subsequent knee surgery based on residual knee laxity. Patients with a difference >6 mm in side-to-side anterior laxity at 2 years postoperatively were noted to have a larger decrease in PROs from 2 to 6 years postoperatively (P < .05). No significant differences in any PROs were noted among patients with a difference <6 mm in side-to-side anterior laxity or those with pivot glide (IKDC B) versus no pivot shift (IKDC A). CONCLUSION: The presence of a residual side-to-side KT-1000 arthrometer difference <6 mm or pivot glide at 2 years after ACLR is not associated with an increased risk of subsequent ipsilateral knee surgery or decreased PROs up to 6 years after ACLR. Conversely, patients exhibiting a difference >6 mm in side-to-side anterior laxity were noted to have significantly decreased PROs at 6 years after ACLR.

ACL Study Group presents the global trends in ACL reconstruction: biennial survey of the ACL Study Group.

OBJECTIVES: The primary objective of this survey was to gauge the current global trends in anterior cruciate ligament reconstruction (ACLR) as reported by the members of the Anterior Cruciate Ligament (ACL) Study Group (SG). METHODS: A survey was created and distributed among the members of the ACL SG consisting of 87 questions and 16 categories related to ACLR, including member demographics, preoperative management, primary ACLR techniques and graft choice, use of concomitant procedures and biological augmentation, postoperative rehabilitation, and more. RESULTS: The survey was completed by the 140 members of the ACL SG. Fifty per cent of members are from Europe, 29% from the USA, 15% from the Asia-Pacific and the remaining 6% are from Latin America, the Middle East, New Zealand and Africa. Most (92%) do not believe there is a role for non-operative management of ACL tears in higher level athletes; conversely, most agree there is a role for non-operative management in lower impact athletes (92%). A single-bundle (90%) technique with hamstring autograft (53%) were most common for primary ACLR. Tunnel position varied among respondents. Sixty-one per cent do not use allograft for primary ACLR. Fifty per cent of respondents use cortical suspensory fixation on the femur, with variable responses on the tibia. Most (79%) do not use biologics in primary ACLR, while 83% think there is a selective role for extra-articular augmentation in primary ACLR. Fifty per cent prefer bone-tendon-bone autograft for revision ACLR and extra-articular augmentation is more commonly used (13% always, 26% often) than in primary ACLR (0% always, 15% often). A majority (53%) use a brace after primary ACLR. The most common responses for minimal time to return to play after primary ACLR were 6-8 months (44%) and 8-12 months (41%). CONCLUSION: We presented the thoughts and preferences of the ACL SG on the management of ACL injuries. This survey will help to facilitate an ongoing discussion with regard to ACLR by providing global insights into the current surgical trends in ACLR. LEVEL OF EVIDENCE: Level V, Expert Opinion.

Articular Cartilage and Meniscus Predictors of Patient-Reported Outcomes 10 Years After Anterior Cruciate Ligament Reconstruction: A Multicenter Cohort Study.

BACKGROUND: Articular cartilage and meniscal damage are commonly encountered and often treated at the time of anterior cruciate ligament reconstruction (ACLR). Our understanding of how these injuries and their treatment relate to outcomes of ACLR is still evolving. HYPOTHESIS/PURPOSE: The purpose of this study was to assess whether articular cartilage and meniscal variables are predictive of 10-year outcomes after ACLR. We hypothesized that articular cartilage lesions and meniscal tears and treatment would be predictors of the International Knee Documentation Committee (IKDC), Knee injury and Osteoarthritis Outcome Score (KOOS) (all 5 subscales), and Marx activity level outcomes at 10-year follow-up after ACLR. STUDY DESIGN: Cohort study (prognosis); Level of evidence, 1. METHODS: Between 2002 and 2008, individuals with ACLR were prospectively enrolled and followed longitudinally using the IKDC, KOOS, and Marx activity score completed at entry, 2, 6, and 10 years. A proportional odds logistic regression model was built incorporating variables from patient characteristics, surgical technique, articular cartilage injuries, and meniscal tears and treatment to determine the predictors (risk factors) of IKDC, KOOS, and Marx outcomes at 10 years. RESULTS: A total of 3273 patients were enrolled (56% male; median age, 23 years at time of enrollment). Ten-year follow-up was obtained on 79% (2575/3273) of the cohort. Incidence of concomitant pathology at the time of surgery consisted of the following: articular cartilage (medial femoral condyle [MFC], 22%; lateral femoral condyle [LFC], 15%; medial tibial plateau [MTP], 4%; lateral tibial plateau [LTP], 11%; patella, 18%; trochlea, 8%) and meniscal pathology (medial, 37%; lateral, 46%). Variables that were predictive of poorer 10-year outcomes included articular cartilage damage in the patellofemoral (P < .01) and medial (P < .05) compartments and previous medial meniscal surgery (7% of knees; P < .04). Compared with no meniscal tear, a meniscal injury was not associated with 10-year outcomes. Medial meniscal repair at the time of ACLR was associated with worse 10-year outcomes for 2 of 5 KOOS subscales, while a medial meniscal repair in knees with grade 2 MFC chondrosis was associated with better outcomes on 2 KOOS subscales. CONCLUSION: Articular cartilage injury in the patellofemoral and medial compartments at the time of ACLR and a history of medial meniscal surgery before ACLR were associated with poorer 10-year ACLR patient-reported outcomes, but meniscal injury present at the time of ACLR was not. There was limited and conflicting association of medial meniscal repair with these outcomes.

The Clinical Radiographic Incidence of Posttraumatic Osteoarthritis 10 Years After Anterior Cruciate Ligament Reconstruction: Data From the MOON Nested Cohort.

BACKGROUND: The incidence of posttraumatic osteoarthritis (PTOA) based on clinical radiographic grading criteria at 10 years after anterior cruciate ligament (ACL) reconstruction (ACLR) has not been well-defined in a prospective cohort of young athletic patients. HYPOTHESIS: Among young athletic patients, there is a high incidence of clinical radiographic PTOA at 10 years after ACLR. Additionally, there is a significant difference in clinical radiographic osteoarthritis (OA) changes (joint space narrowing and osteophyte formation) between ACL-reconstructed and contralateral knees at 10 years. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: The first 146 patients in an ongoing nested cohort study of the Multicenter Orthopaedic Outcomes Network (MOON) prospective cohort presented for a minimum 10-year follow-up. Included patients had a sports-related ACL injury, were aged <33 years at the time of ACLR, had no history of ipsilateral or contralateral knee surgery, and did not undergo revision ACLR before follow-up. Bilateral knee metatarsophalangeal view radiographs were obtained and graded according to International Knee Documentation Committee (IKDC), Osteoarthritis Research Society International (OARSI), and modified Kellgren-Lawrence (KL) criteria by 2 blinded reviewers. The incidence and severity of ipsilateral and contralateral radiographic OA were determined among patients without a contralateral ACL injury before 10-year follow-up (N = 133). RESULTS: Interrater reliability was substantial for the IKDC (Gwet Agreement Coefficient [AC] 1 = 0.71), moderate for the KL (0.48), and almost perfect for the OARSI (0.84) grading systems. Among patients with a contralateral radiographically normal knee, the 10-year incidence of clinical radiographic PTOA after ACLR was 37% as defined by osteophytes and 23% as defined by joint space narrowing. The maximum side-to-side difference in the OARSI osteophyte grade in the medial or lateral compartment was 0 in 65% of patients, 1 in 20%, and ≥2 in 15%. The maximum side-to-side difference in the OARSI joint space narrowing grade was 0 in 77% of patients, 1 in 19%, and ≥2 in 4%. CONCLUSION: In young active patients, the 10-year incidence of clinical radiographic PTOA after ACLR was 37% as defined by osteophytes and 23% as defined by joint space narrowing. The mean difference in the degree of osteophyte formation (≤1 grade in 85%) and joint space narrowing (≤1 grade in 96%) between the ACL-reconstructed and contralateral knees was small. REGISTRATION: NCT02717559 (ClinicalTrials.gov identifier).

Same knee, different goals: patients and surgeons have different priorities related to ACL reconstruction.

PURPOSE: The priorities of patients should be shared by those treating them. Patients and surgeons are likely to have different priorities surrounding anterior cruciate ligament reconstruction (ACLR), with implications for shared decision-making and patient education. The optimal surgical approach for ACLR is constantly evolving, and the magnitude of treatment effect necessary for evidence to change surgical practice is unknown. The aim of this study was to determine (1) the priorities of surgeons and patients when making decisions regarding ACLR and (2) the magnitude of reduction in ACLR graft failure risk that orthopaedic surgeons require before changing practice. METHODS: This study followed a cross-sectional survey design. Three distinct electronic surveys were administered to pre-operative ACLR patients, post-operative ACLR patients, and orthopaedic surgeons. Patients and surgeons were asked about the importance of various outcomes and considerations pertaining to ACLR. Surgeons were asked scenario-based questions regarding changing practice for ACLR based on new research. RESULTS: Surgeons were more likely to prioritize outcomes related to the surgical knee itself, whereas patients were more likely to prioritize outcomes related to their daily lifestyle and activities. Knee instability and risk of re-injury were unanimous top priorities among all three groups. A mean relative risk reduction in ACLR graft failure of about 50% was required by orthopaedic surgeons to change practice regardless of the type of change, or patient risk profile. CONCLUSION: There are discrepancies between the priorities of surgeons and patients, and orthopaedic surgeons appear resistant to changing practice for ACLR. LEVEL OF EVIDENCE: IV.

Differences in brain structure and theta burst stimulation-induced plasticity implicate the corticomotor system in loss of function after musculoskeletal injury.

Traumatic musculoskeletal injury (MSI) may involve changes in corticomotor structure and function, but direct evidence is needed. To determine the corticomotor basis of MSI, we examined interactions among skeletomotor function, corticospinal excitability, corticomotor structure (cortical thickness and white matter microstructure), and intermittent theta burst stimulation (iTBS)-induced plasticity. Nine women with unilateral anterior cruciate ligament rupture (ACL) 3.2 ± 1.1 yr prior to the study and 11 matched controls (CON) completed an MRI session followed by an offline plasticity-probing protocol using a randomized, sham-controlled, double-blind, cross-over study design. iTBS was applied to the injured (ACL) or nondominant (CON) motor cortex leg representation (M1LEG) with plasticity assessed based on changes in skeletomotor function and corticospinal excitability compared with sham iTBS. The results showed persistent loss of function in the injured quadriceps, compensatory adaptations in the uninjured quadriceps and both hamstrings, and injury-specific increases in corticospinal excitability. Injury was associated with lateralized reductions in paracentral lobule thickness, greater centrality of nonleg corticomotor regions, and increased primary somatosensory cortex leg area inefficiency and eccentricity. Individual responses to iTBS were consistent with the principles of homeostatic metaplasticity; corresponded to injury-related differences in skeletomotor function, corticospinal excitability, and corticomotor structure; and suggested that corticomotor adaptations involve both hemispheres. Moreover, iTBS normalized skeletomotor function and corticospinal excitability in ACL. The results of this investigation directly confirm corticomotor involvement in chronic loss of function after traumatic MSI, emphasize the sensitivity of the corticomotor system to skeletomotor events and behaviors, and raise the possibility that brain-targeted therapies could improve recovery.NEW & NOTEWORTHY Traumatic musculoskeletal injuries may involve adaptive changes in the brain that contribute to loss of function. Our combination of neuroimaging and theta burst transcranial magnetic stimulation (iTBS) revealed distinct patterns of iTBS-induced plasticity that normalized differences in muscle and brain function evident years after unilateral knee ligament rupture. Individual responses to iTBS corresponded to injury-specific differences in brain structure and physiological activity, depended on skeletomotor deficit severity, and suggested that corticomotor adaptations involve both hemispheres.

TIMELINE OF GAINS IN QUADRICEPS STRENGTH SYMMETRY AND PATIENT-REPORTED FUNCTION EARLY AFTER ACL RECONSTRUCTION.

BACKGROUND: Quadriceps weakness is a predictor of long-term knee function and strength recovery can vary from months to years after anterior cruciate ligament reconstruction (ACLR). However, few studies evaluate quadriceps strength and self-reported function within the first several weeks after ACLR. HYPOTHESIS/PURPOSE: To examine changes over time in quadriceps strength symmetry, quadriceps peak torque, and self-reported knee function prior to and at six, 12, and 24 weeks post-ACLR. The hypotheses were 1) quadriceps strength symmetry, bilateral quadriceps peak torque, and patient-reported function would improve over time from pre-ACLR to 24 weeks post-ACLR and 2) significant improvements in patient-reported function, but not strength symmetry, would occur between time points. STUDY DESIGN: Prospective, cohort study. METHODS: Thirty participants completed four testing sessions: pre-surgery and six, 12, and 24 weeks post-ACLR. Isometric quadriceps strength testing was performed at six weeks and isokinetic quadriceps strength was measured at all other testing points. Quadriceps index was calculated to evaluate between limb quadriceps strength symmetry. The Knee injury and Osteoarthritis Outcome Score (KOOS) and International Knee Documentation Committee Subjective Knee Evaluation Form (IKDC) were administered at each time point. A repeated-measures analysis of variance evaluated changes over time, with post-hoc comparisons to determine at which time-point significant changes occurred. RESULTS: Quadriceps strength symmetry, involved limb quadriceps peak torque and all patient-reported outcome scores increased over time (p<0.02). Post-hoc tests showed that neither self-reported outcomes, nor quadriceps index improved between pre-surgery and six-weeks post-ACLR. From six to 12 weeks post-ACLR, scores on IKDC and KOOS Pain, Symptoms, Quality of Life, and Sport subscales improved (p≤0.003). From 12 to 24 weeks post-ACLR, quadriceps strength symmetry, involved limb quadriceps peak torque, KOOS-Symptoms, Quality of Life, and Sport subscales and the IKDC improved (p≤0.01). Uninvolved limb quadriceps peak torque did not change across any time point (p≥0.18). CONCLUSION: Patient-reported knee function increased between six and 24 weeks post-ACLR, while increases in involved limb quadriceps strength and quadriceps strength symmetry were not noted until 12-24 weeks post-ACLR. LEVEL OF EVIDENCE: 2b, individual cohort study.