Influence of backside seating parameters and augmented baseplate components in virtual planning for reverse shoulder arthroplasty.

BACKGROUND: The primary goal of this investigation was to examine the influence of a backside seating percentage variable on volume of reamed bone and contact area in virtual planning for glenoid baseplate placement for reverse total shoulder arthroplasty (RTSA). The secondary goal was to assess how the option of augmented glenoid baseplate components affected reamed volume and cortical contact area of virtually positioned baseplates. METHODS: Nine surgeons virtually planned 30 RTSA cases using a commercially available software system. The 30 cases were chosen to span a spectrum of glenoid deformity. The study consisted of 3 phases. In phase 1, cases were planned with the backside seating percentage blinded and without the option of augmented baseplate components. In phase 2, the backside seating parameter was unblinded. In phase 3, augmented baseplate components were added as an option. Implant version and inclination were recorded. By use of computer-assisted design models, total volume of bone reamed, as well as reamed cortical volume and cancellous volume, was calculated. Total, cortical, and cancellous baseplate contact areas were also calculated. Finally, total glenoid lateralization was calculated for each phase and compared. RESULTS: Mean implant version was clinically similar across phases but was statistically significantly lower in phase 3 (P = .006 compared with phase 1 and P = .001 compared with phase 2). Mean implant inclination was clinically similar across phases but was statistically significantly lower in phase 3 (P < .001). Phase 3 had statistically significantly lower cancellous and total reamed bone volumes compared with phase 1 and phase 2 (P < .001 for all comparisons). Phase 3 had statistically significantly larger cortical contact area, lower cancellous contact area, and larger total contact area compared with phase 1 and phase 2 (P < .001 for all comparisons). Phase 3 had significantly greater glenoid lateralization (mean, 10.5 mm) compared with phase 1 (mean, 7.8 mm; P < .001) and phase 2 (mean, 7.9 mm; P < .001). CONCLUSIONS: Across a wide range of glenoid pathology during virtual surgical planning, experienced shoulder arthroplasty surgeons chose augmented baseplates frequently, and the option of a full-wedge augmented baseplate resulted in statistically significantly greater correction of glenoid deformity, improved total and cortical baseplate contact area, less cancellous reamed bone, and greater glenoid lateralization. Backside seating information does not have a significant impact on how glenoid baseplates are virtually positioned for RTSA, nor does it impact the baseplate contact area or volume of reamed bone.

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.

Prescribing Fewer Opioids After Rotator Cuff Repair and Anterior Cruciate Ligament Reconstruction Lowers Opioid Consumption Without Impacting Patient-Reported Pain Scores.

Purpose: To develop a standardized opioid prescribing schedule (SOPS) following anterior cruciate ligament reconstruction (ACLR) and rotator cuff repair (RCR) and evaluate postoperative opioid consumption alongside Patient-Reported Outcome Measurement Information System (PROMIS) pain interference scores. Methods: A prospective observational study was performed on all patients undergoing primary ACLR and RCR from March 2019 to October 2021. Patients taking opioids preoperatively and revision ACLR and RCR were excluded. PROMIS 6B questionnaires were administered before and after implantation of the SOPS initiated on December 15, 2019. Opioid consumption was determined by email surveys. Hypothesis testing was performed with Mann-Whitney U test. Results: A total of 599 patients met inclusion criteria with 188 patients (71 ACLR and 117 RCR) completing surveys. Before the initiation of SOPS, the average number of oxycodone 5-mg tablets prescribed for ACLR was 44.6 (95% confidence interval [CI] 42.4-46.9) and for RCR was 44.7 (95% CI 42.7-46.8). The average usage was 23.1 (95% CI 16.9-29.2) and 22.1 (95% CI 16.2-28.0), respectively. Following SOPS of 30 tablets of oxycodone 5 mg for ACLR and 40 tablets for RCR, the average number of tablets prescribed significantly decreased for both procedures (P < .01 for ACLR and RCR), and the average consumption decreased to 20.5 (95% CI 16.6-24.4) and 18.6 (95% CI 14.6-22.5), respectively. PROMIS 6B responses did not demonstrate statistically significant changes following SOPS. Conclusions: The results of the present study demonstrate that the implementation of a SOPS reduced postoperative opioid prescribing amounts and consumption without significant impacting PROMIS pain interference scores for ACLR and RCR, supporting the possibility to decrease and standardize opioid prescribing following common sports medicine procedures. Level of Evidence: III: Retrospective, comparative, therapeutic study.

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.

Glenohumeral Hydrodistension for Postoperative Stiffness After Arthroscopic Primary Rotator Cuff Repair.

Background: Postoperative stiffness is a known complication after rotator cuff repair (RCR). Glenohumeral hydrodistension (GH) has been a treatment modality for shoulder pathology but has not been used to treat postoperative stiffness after RCR. Purpose/Hypothesis: The purpose of this study was to identify the risk factors for postoperative stiffness after RCR and review outcomes after treatment with GH. Our hypotheses were that stiffness would be associated with diabetes and hyperlipidemia and correlated with the tendons involved and that patients with stiffness who underwent GH would have significant improvement in range of motion (ROM). Study Design: Case series; Level of evidence, 4. Methods: Included were 388 shoulders of patients who underwent primary RCR by a single surgeon between 2015 and 2019. Shoulders with revision RCRs were excluded. Patient characteristics, medical comorbidities, and perioperative details were collected. A total of 40 shoulders with postoperative stiffness (10.3%) received GH injectate of a 21-mL mixture (15 mL of sterile water, 5 mL of 0.5% ropivacaine, and 1 mL of triamcinolone [10 mg/mL]). The primary outcome measure was ROM in forward flexion, internal rotation, external rotation, and abduction. Statistical tests were performed using analysis of variance. Results: Patients with diabetes had significantly decreased internal rotation at final follow-up after RCR as compared with patients without diabetes. GH to treat stiffness was performed most commonly between 1 and 4 months after RCR (60%), and patients who received GH saw statistically significant improvements in forward flexion, external rotation, and abduction after the procedure. Patients with hyperlipidemia had the most benefit after GH. Among those undergoing concomitant procedures, significantly more patients who had open subpectoral biceps tenodesis underwent GH. Patients who underwent subscapularis repair or concomitant subacromial decompression had significant improvement in ROM after GH. Only 1 patient who received GH underwent secondary surgery for resistant postoperative stiffness. Conclusion: Patients with diabetes had increased stiffness. Patients with a history of hyperlipidemia or concomitant open subpectoral biceps tenodesis were more likely to undergo GH for postoperative stiffness. Patients who underwent subscapularis repair demonstrated the most improvement in ROM after GH. After primary RCR, GH can increase ROM and is a useful adjunct for patients with stiffness to limit secondary surgery.

Short-term clinical and radiographic outcomes of a hybrid all-polyethylene glenoid based on preoperative glenoid morphology.

BACKGROUND: The primary purpose of this study was to compare 2-year anatomic total shoulder arthroplasty (TSA) functional and radiographic outcomes between Walch type A and B glenoids treated with an all-polyethylene glenoid designed for hybrid fixation with peripheral cement and central osseous integration. The secondary purpose was to evaluate outcomes based on central peg technique. The hypotheses were that there would be no difference in short-term radiographic or functional outcome scores based on preoperative glenoid morphology or central peg technique. METHODS: We performed a multicenter retrospective review of patients who underwent TSA with the same hybrid all-polyethylene glenoid and had minimum 2-year follow-up. Patient-reported outcomes and radiographic outcomes were analyzed based on preoperative Walch morphology and central peg technique. Radiographic analysis included preoperative glenoid morphology; preoperative and postoperative glenoid version, glenoid inclination, and posterior humeral head subluxation; and postoperative glenoid radiolucencies according to the Wirth and Lazarus classifications. RESULTS: A total of 266 patients with a mean age of 64.9 ± 8.2 years were evaluated at a mean of 28 months postoperatively. Postoperatively, there were significant improvements in all functional outcome measures (P < .001), range-of-motion measures (forward elevation, external rotation at 0°, external rotation at 90°, internal rotation by spinal level, and internal rotation at 90°; P < .001), and strength measures (Constant, external rotation, and modified belly press; P < .001). There were no clinically meaningful differences in functional outcomes or statistically significant differences in radiographic appearance between Walch type A and B glenoids. Subgroup analysis revealed that glenoids with a cemented central peg had the worst radiographic outcomes based on Lazarus scoring. CONCLUSION: Patients undergoing TSA with a hybrid in-line pegged glenoid have excellent clinical outcomes at short-term follow-up regardless of preoperative glenoid morphology. Different central peg techniques do not appear to play a significant role in the risk of glenoid component lucencies at 2 years postoperatively.

Computational Metrics Can Provide Quantitative Values to Characterize Arthroscopic Field of View.

Purpose: The purpose of this study was to determine the inter-rater reliability of arthroscopic video quality, determine correlation between surgeon rating and computational image metrics, and facilitate a quantitative methodology for assessing video quality. Methods: Five orthopaedic surgeons reviewed 60 clips from deidentified arthroscopic shoulder videos and rated each on a four-point Likert scale from poor to excellent view. The videos were randomized, and the process was completed a total of three times. Each user rating was averaged to provide a user rating per clip. Each video frame was processed to calculate brightness, local contrast, redness (used to represent bleeding), and image entropy. Each metric was then averaged over each frame per video clip, providing four image quality metrics per clip. Results: Inter-rater reliability for grading video quality had an intraclass correlation of .974. Improved image quality rating was positively correlated with increased entropy (.8142; P < .001), contrast (.8013; P < .001), and brightness (.6120; P < .001), and negatively correlated with redness (-.8626; P < .001). A multiple linear regression model was calculated with the image metrics used as predictors for the image quality ranking, with an R-squared value of .775 and root mean square error of .42. Conclusions: Our study demonstrates strong inter-rater reliability between surgeons when describing image quality and strong correlations between image quality and the computed image metrics. A model based on these metrics enables automatic quantification of image quality. Clinical Relevance: Video quality during arthroscopic cases can impact the ease and duration of the case which could contribute to swelling and complication risk. This pilot study provides a quantitative method to assess video quality. Future works can objectively determine factors that affect visualization during arthroscopy and identify options for improvement.

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.

Clinical and Radiological Outcomes in Reverse Total Shoulder Arthroplasty by Inclination Angle With a Modular Prosthesis.

The influence of the humeral inclination in reverse total shoulder arthroplasty (RTSA) is not well understood. The purpose of this study was to determine outcomes and complications after RTSA with an inclination of 135° or 155° in a modular prosthesis. American Shoulder and Elbow Surgeons (ASES), visual analog scale (VAS), Single Assessment Numeric Evaluation (SANE), and Simple Shoulder Test (SST) scores, as well as forward elevation (FE), abduction (ABD), and external rotation (ER), were assessed after a minimum 2-year follow-up. Scapular notching and radiolucency were assessed according to Sirveaux and Lévigne. A total of 121 patients with a mean age of 69.7±7.3 years were evaluated after a mean of 36.5±8 months. The inclination was set to 135° in 80.2% and to 155° in 19.8% of patients. There was no significant difference between the groups for ASES, VAS, SANE, and SST scores. The FE (P=.022) and ABD (P=.002) were significantly higher for the 155° inclination group. Complication rates were not significantly different between the groups. Scapular notching was significantly more common with a 155° inclination (P=.01), whereas humeral radiolucency was not correlated. All outcome scores improved significantly from pre- to postoperative (P≤.001). Reverse total shoulder arthroplasty leads to significant improvements in pain, range of motion, and outcome scores after mid-term follow-up. Overall, the inclination angle does not significantly affect clinical outcomes or the complication rate after RTSA at mid-term follow-up. However, an inclination of 155° shows significantly greater FE and ABD, although it results in a significantly higher rate of scapular notching. Cases with scapular notching are associated with significantly reduced mean ASES scores and ER as well as significantly higher VAS scores. [Orthopedics. 2021;44(4):e527-e533.].

Negligible Correlation between Radiographic Measurements and Clinical Outcomes in Patients Following Primary Reverse Total Shoulder Arthroplasty.

Previous attempts to measure lateralization, distalization or inclination after reverse total shoulder arthroplasty (rTSA) and to correlate them with clinical outcomes have been made in the past years. However, this is considered to be too demanding and challenging for daily clinical practice. Additionally, the reported findings were obtained from heterogeneous rTSA cohorts using 145° and 155° designs and are limited in external validity. The purpose of this study was to investigate the prognostic preoperative and postoperative radiographic factors affecting clinical outcomes in patients following rTSA using a 135° prosthesis design. In a multi-center design, patients undergoing primary rTSA using a 135° design were included. Radiographic analysis included center of rotation (COR), acromiohumeral distance (AHD), lateral humeral offset (LHO), distalization shoulder angle (DSA), lateralization shoulder angle (LSA), critical shoulder angle (CSA), and glenoid and baseplate inclination. Radiographic measurements were correlated to clinical and functional outcomes, including the American Shoulder and Elbow Surgeons (ASES), Simple Shoulder Test (STT), Single Assessment Numeric Evaluation (SANE), and Visual Analogue Scale (VAS) score, active forward elevation (AFE), external rotation (AER), and abduction (AABD), at a minimum 2-year follow-up. There was a significant correlation between both DSA (r = 0.299; p = 0.020) and LSA (r = -0.276; p = 0.033) and the degree of AFE at final follow-up. However, no correlation between DSA (r = 0.133; p = 0.317) and LSA (r = -0.096; p = 0.471) and AER was observed. Postoperative AHD demonstrated a significant correlation with final AFE (r = 0.398; p = 0.002) and SST (r = 0.293; p = 0.025). Further, postoperative LHO showed a significant correlation with ASES (r = -0.281; p = 0.030) and LSA showed a significant correlation with ASES (r = -0.327; p = 0.011), SANE (r = -0.308, p = 0.012), SST (r = -0.410; p = 0.001), and VAS (r = 0.272; p = 0.034) at terminal follow-up. All other correlations were found to be non-significant (p > 0.05, respectively). Negligible correlations between pre- and postoperative radiographic measurements and clinical outcomes following primary rTSA using a 135° prosthesis design were demonstrated; however, these observations are of limited predictive value for outcomes following rTSA. Subsequently, there remains a debate regarding the ideal placement of the components during rTSA to most sufficiently restore active ROM while minimizing complications such as component loosening and scapular notching. Additionally, as the data from this study show, there is still a considerable lack of data in assessing radiographic prosthesis positioning in correlation to clinical outcomes. As such, the importance of radiographic measurements and their correlation with clinical and functional outcomes following rTSA may be limited.

Changes in Infrapatellar Fat Pad Volume 6 to 12 Months After Anterior Cruciate Ligament Reconstruction and Associations With Patient-Reported Knee Function.

CONTEXT: Hypertrophy of the infrapatellar fat pad (IFP) in idiopathic knee osteoarthritis has been linked to deleterious synovial changes and joint pain related to mechanical tissue impingement. Yet little is known regarding the IFP's volumetric changes after anterior cruciate ligament reconstruction (ACLR). OBJECTIVES: To examine changes in IFP volume between 6 and 12 months after ACLR and determine associations between patient-reported outcomes and IFP volume at each time point as well as the volume change over time. In a subset of individuals, we examined interlimb IFP volume differences 12 months post-ACLR. STUDY DESIGN: Prospective cohort study. SETTING: Laboratory. PATIENTS OR OTHER PARTICIPANTS: We studied 26 participants (13 women, 13 men, age = 21.88 ± 3.58 years, body mass index = 23.82 ± 2.21 kg/m2) for our primary aims and 13 of those participants (8 women, 5 men, age = 21.15 ± 3.85 years, body mass index = 23.01 ± 2.01 kg/m2) for our exploratory aim. MAIN OUTCOME MEASURE(S): Using magnetic resonance imaging, we evaluated the IFP volume change between 6 and 12 months post-ACLR in the ACLR limb and between-limbs differences at 12 months in a subset of participants. International Knee Documentation Committee subjective knee evaluation (IKDC) scores were collected at 6-month and 12-month follow-ups, and associations between IFP volume and patient-reported outcomes were determined. RESULTS: The IFP volume in the ACLR limb increased from 6 months (19.67 ± 6.30 cm3) to 12 months (21.26 ± 6.91 cm3) post-ACLR. Greater increases of IFP volume between 6 and 12 months were significantly associated with better 6-month IKDC scores (r = .44, P = .03). The IFP volume was greater in the uninjured limb (22.71 ± 7.87 cm3) than in the ACLR limb (20.75 ± 9.03 cm3) 12 months post-ACLR. CONCLUSIONS: The IFP volume increased between 6 and 12 months post-ACLR; however, the IFP volume of the ACLR limb remained smaller than that of the uninjured limb at 12 months. In addition, those with better knee function 6 months post-ACLR demonstrated greater increases in IFP volume between 6 and 12 months post-ACLR. This suggests that greater IFP volumes may play a role in long-term joint health after ACLR.

Gait Biomechanics in Individuals Meeting Sufficient Quadriceps Strength Cutoffs After Anterior Cruciate Ligament Reconstruction.

CONTEXT: Quadriceps weakness is associated with disability and aberrant gait biomechanics after anterior cruciate ligament reconstruction (ACLR). Strength-sufficiency cutoff scores, which normalize quadriceps strength to the mass of an individual, can predict who will report better function after ACLR. However, whether gait biomechanics differ between individuals who meet a strength-sufficiency cutoff (strong) and those who do not (weak) remains unknown. OBJECTIVE: To determine whether vertical ground reaction force, knee-flexion angle, and internal knee-extension moment differ throughout the stance phase of walking between individuals with strong and those with weak quadriceps after ACLR. DESIGN: Case-control study. SETTING: Laboratory. PATIENTS OR OTHER PARTICIPANTS: Individuals who underwent unilateral ACLR >12 months before testing were dichotomized into strong (n = 31) and weak (n = 116) groups. MAIN OUTCOME MEASURES: Maximal isometric quadriceps strength was measured at 90° of knee flexion using an isokinetic dynamometer and normalized to body mass. Individuals who demonstrated maximal isometric quadriceps strength ≥3.0 N·m·kg-1 were considered strong. Three-dimensional gait biomechanics were collected at a self-selected walking speed. Biomechanical data were time normalized to 100% of stance phase. Vertical ground reaction force was normalized to body weight (BW), and knee-extension moment was normalized to BW × height. Pairwise comparison functions were calculated for each outcome to identify between-groups differences for each percentile of stance. RESULTS: Vertical ground reaction force was greater in the weak group for the first 22% of stance (peak mean difference [MD] = 6.2% BW) and less in the weak group between 36% and 43% of stance (MD = 1.4% BW). Knee-flexion angle was greater (ie, more flexion) in the strong group between 6% and 52% of stance (MD = 2.3°) and smaller (ie, less flexion) between 68% and 79% of stance (MD = 1.0°). Knee-extension moment was greater in the strong group between 7% and 62% of stance (MD = 0.007 BW × height). CONCLUSIONS: Individuals with ACLR who generated knee-extension torque ≥3.0 N·m·kg-1 exhibited different biomechanical gait profiles than those who could not. More strength may allow for better energy attenuation after ACLR.

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.

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).

Time between anterior cruciate ligament injury and reconstruction and cartilage metabolism six-months following reconstruction.

BACKGROUND: To determine the association between time from injury to ACL reconstruction (TimeInjury-ACLR) and biochemical markers of cartilage metabolism and inflammation six months following ACL reconstruction (ACLR). METHODS: Individuals with a unilateral ACL injury were enrolled at initial presentation in the orthopedic clinic; blood was collected six months following ACLR. Enzyme-linked immunosorbent assays were used to analyze the ratio of serum concentrations of type-II collagen breakdown (C2C) to synthesis (CPII), plasma matrix metalloproteinase-3 (MMP-3), interleukin-6 (IL-6), and serum aggrecan neoepitope (ARGS). We used separate linear regressions to assess associations between biochemical markers and TimeInjury-ACLR. RESULTS: Twenty-two participants (50% females, mean [SD], age 21.9 [4.5] years old; BMI 23.8 [2.6] kg/m2) completed the study. TimeInjury-ACLR ranged from nine to 67days (31.0 [14.4days]). Greater TimeInjury-ACLR predicted greater serum C2C:CPII ratios six months following ACLR (C2C:CPII=0.15 [0.02], R2=0.213, P=0.030). Males (R2=0.733, P=0.001) but not females (R2=0.030, P=0.609) demonstrated a significant association between greater C2C:CPII and TimeInjury-ACLR at the six-month follow-up exam. TimeInjury-ACLR did not associate with IL-6, MMP-3, or ARGS at six months. CONCLUSIONS: Greater time between injury and ACL reconstruction was associated with greater serum C2C:CPII six months following ACLR in males but not females, and IL-6, MMP-3, and ARGS levels were not associated with TimeInjury-ACLR in males or females. The time between ACL injury and ACLR may affect collagen metabolism in males and should be further investigated in a larger study along with other patient-relevant outcomes.

Use of a Small-Bore Needle Arthroscope to Diagnose Intra-Articular Knee Pathology: Comparison With Magnetic Resonance Imaging.

The use of arthroscopy for purely diagnostic purposes has been largely supplanted by noninvasive technologies, such as magnetic resonance imaging (MRI). The mi-eye+TM (Trice Medical) technology is a small-bore needle unit for in-office arthroscopy. We conducted a pilot study comparing the mi-eye⁺™ unit with MRI, using surgical arthroscopy as a gold-standard reference. We hypothesized that the mi-eye⁺™ needle arthroscope, which can be used in an office setting, would be equivalent to MRI for the diagnosis of intra-articular pathology of the knee. This prospective, multicenter, observational study was approved by the Institutional Review Board. There were 106 patients (53 males, 53 females) in the study. MRIs were interpreted by musculoskeletally trained radiologists. The study was conducted in the operating room using the mi-eye⁺™ device. The mi-eye⁺™ device findings were compared with the MRI findings within individual pathologies, and a "per-patient" analysis was performed to compare the arthroscopic findings with those of the mi-eye⁺™ and the MRI. Additionally, we identified all mi-eye⁺™ findings and MRI findings that exactly matched the surgical arthroscopy findings. The mi-eye⁺™ demonstrated complete accuracy of all pathologies for 97 (91.5%) of the 106 patients included in the study, whereas MRI demonstrated complete accuracy for 65 patients (61.3%) (P < .0001). All discrepancies between mi-eye⁺TM and arthroscopy were false-negative mi-eye⁺™ results, as the mi-eye⁺TM did not reveal some aspect of the knee's pathology for 9 patients. The mi-eye⁺™ was more sensitive than MRI in identifying meniscal tears (92.6% vs 77.8%; P = .0035) and more specific in diagnosing these tears (100% vs 41.7%; P < .0001). The mi-eye⁺™ device proved to be more sensitive and specific than MRI for intra-articular findings at time of knee arthroscopy. Certainly there are contraindications to using the mi-eye⁺™, and our results do not obviate the need for MRI, but our study did demonstrate that the mi-eye⁺™ needle arthroscope can safely provide excellent visualization of intra-articular knee pathology.

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.

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.