Stuart, Michael J.

Purpose To develop a standardized method for tibial tunnel volumetric bone mineral density (BMD) analysis with quantitative computed tomography (qCT) using cadaveric specimens to provide validation of this technique on a healthy control population and to determine whether osteopenia occurs following an anterior cruciate ligament (ACL) injury. Methods: qCT was used to develop a volumetric BMD (mg/cm 3 ) measurement technique throughout the region of a standard tibial tunnel. This method was applied to 90 lower extremities, including 10 matched cadaveric knees, 10 matched healthy knees, 25 ACL‐injured knees, and 25 contralateral ACL‐uninjured knees. The mean total and segmental (proximal, middle, and distal) tibial tunnel BMD were analyzed. Results The mean entire tibial tunnel BMD measured 165.8 ± 30.5 mg/cm 3 (cadaver), 255.9 ± 28.2 mg/cm 3 (healthy control), 290.3 ± 36.4 mg/cm 3 (ACL‐injured), and 300.1 ± 35.1 (ACL‐uninjured). Segmental tibial tunnel BMD demonstrated distal one‐third segments as the greatest areas of BMD, followed by proximal one‐third, and middle one‐third for all cohorts with all pairwise comparisons ( P < .001). The mean BMD was significantly greater in the uninjured extremity compared with the injured extremity in the entire tunnel (290.3 vs 300.1; P < .001), proximal (271.2 vs 279.1; P = .002), middle (167.6 vs 179.6; P < .001), and distal segments (432.7 vs 441.7; P = .004) at an average of 8 weeks following ACL injury. Conclusions A standardized method to quantitatively measure the volumetric BMD within the region of a standard tibial tunnel for ACL reconstruction was successfully developed and validated. Significant osteopenia of the injured knee occurs following ACL injury when compared with the contralateral uninjured knee. This observation has potential clinical implications for ACL graft tibial fixation and healing. Level of Evidence Descriptive diagnostic study, Level III.

Background: Lateral meniscal oblique radial tears (LMORT) occur frequently in conjunction with anterior cruciate ligament (ACL) disruption and are anatomically distinct from meniscus root tears. Hypothesis/Purpose: The purpose of this study was to characterize the effects of LMORT types 3 (LMORT3) and 4 (LMORT4) lesions on joint stability and meniscal extrusion in ACL-deficient knees. Our hypothesis was that both lesions would promote significant increases in anterior translation and meniscal extrusion, with the LMORT4 lesion having a greater effect. Study Design: Controlled laboratory study. Methods: Two matched pairs of cadaveric knees (n = 4) were used to optimize the testing sequence. Additional cadaveric knees with LMORT3 (n = 8) and LMORT4 (n = 8) lesions created after ACL transection underwent robotic kinematic testing for anterior drawer and pivot-shift simulations with associated ultrasound-measured meniscal extrusion at clinically relevant knee flexion angles. Results: Optimization testing showed no differences on the effect of LMORT4 lesions for anterior translation and lateral meniscal extrusion with ACL-intact versus ACL-deficient knees. ACL deficiency and LMORT3 and LMORT4 lesions with ACL deficiency were associated with significantly greater anterior translation compared with ACL-intact state for both anterior drawer and pivot-shift testing at all flexion angles ( P < .001). ACL deficiency with either LMORT3 or LMORT4 lesion was associated with significantly greater anterior translation than was ACL deficiency only ( P < .005) for anterior drawer testing at 90° of flexion. Meniscal extrusion was greater with LMORT3 and LMORT4 lesions compared with ACL deficiency only ( P < .05) for anterior drawer at 60° of flexion and for pivot shift at 15° of flexion. The LMORT4 lesion demonstrated increased anterior translation for anterior drawer ( P = .003) at 60° of flexion (12%) as well as for pivot shift at 15° of flexion (7%) and 30° of flexion (13%) ( P < .005) compared with ACL deficiency only. Conclusion: In this cadaveric model, the addition of an LMORT3 or LMORT4 lesion increased anterior laxity for both the anterior drawer and the pivot shift when compared with an isolated ACL tear. Lateral meniscal extrusion was also exacerbated by these LMORT lesions. Clinical Relevance: LMORT lesions, distinct from meniscus root tears, occur frequently in conjunction with ACL tears. This study characterized the biomechanical consequences of LMORT3 and LMORT4 lesions on joint stability and meniscal function, highlighting the importance of diagnosing and treating LMORT lesions at the time of ACL reconstruction.

Background: The loss of extensor mechanism continuity that occurs with patellar and quadriceps tendon rupture has devastating consequences on patient function. Purpose: To describe a treatment strategy for extensor mechanism disruption and evaluate the outcomes of 3 techniques: primary repair, repair with semitendinosus tendon autograft augmentation, and reconstruction with Achilles tendon allograft. Study Design: Case series; Level of evidence, 4. Methods: The authors reviewed surgeries for extensor mechanism disruption performed by a single surgeon between 1999 and 2019. Patient characteristics, imaging studies, surgical techniques, and outcomes were recorded. Primary ruptures with robust tissue quality were repaired primarily, and first-time ruptures with significant tendinosis or moderate tissue loss were repaired using quadrupled semitendinosus tendon autograft augmentation. Patients with failed previous extensor mechanism repair or reconstruction and poor tissue quality underwent reconstruction with Achilles tendon allograft. The primary outcome was extensor mechanism integrity at a minimum 1-year follow-up, with extensor mechanism lag defined as >5° loss of terminal, active knee extension. Secondary outcomes included postoperative knee range of motion, International Knee Documentation Committee (IKDC) and Tegner activity scores, and the radiographic Caton-Deschamps Index. Results: Included were 22 patellar tendon and 21 quadriceps tendon surgeries (patients: 82.5% male; mean age, 48.1 years; body mass index, 31). Seventeen (39.5%) cases underwent primary tendon repair, 13 (30.2%) had repair using semitendinosus tendon autograft augmentation, and 13 (30.2%) underwent reconstruction using an Achilles tendon allograft. Seventeen (39.5%) cases had at least 1 prior failed extensor mechanism surgery performed at an outside facility. At the last follow-up, 4 (9.3%) cases had an extensor mechanism lag, no cases required additional extensor mechanism surgery, and all cases were able to achieve >90° of knee flexion. Postoperative IKDC scores were significantly improved with all methods of extensor mechanism surgery, and postoperative Tegner activity scores were significantly improved in patients who underwent primary repair and Achilles tendon allograft reconstruction ( P < .05 for all). Conclusion: Primary repair alone, repair using quadrupled semitendinosus tendon autograft augmentation, and reconstruction using Achilles tendon allograft were all effective methods to restore extensor mechanism and knee function with the proper indications. Persistent knee extensor lag was more common in chronic extensor mechanism injuries after failed surgery, although patients still reported significantly improved postoperative functional outcomes.

Background: Meniscal tears are common in active patients, but treatment trends and surgical outcomes in young patients with lateral meniscal tears are lacking. Purpose: To evaluate treatment trends, outcomes, and failure rates in young patients with lateral meniscal tears. Study Design: Cohort study; Level of evidence, 3. Methods: Patients aged ≤25 years treated surgically for isolated lateral meniscal tears from 2001 to 2017 were identified. Treatment trends were compared over time. International Knee Documentation Committee (IKDC) scores and failure rates were compared by treatment modality (meniscectomy vs meniscal repair). Failure was defined as reoperation, symptomatic osteoarthritis, or a severely abnormal IKDC score. Univariate regression analyses were performed to predict failure and IKDC scores based on treatment, type and location of tear, or extent of meniscectomy. Results: Included were 217 patients (226 knees) with a mean age of 17.4 years (range, 7-25 years); of these patients, 144 knees (64%) were treated with meniscectomy and 82 knees (36%) with meniscal repair. Treatment with repair increased over time compared with meniscectomy ( P < .001). At a minimum 2-year follow-up (mean, 6.1 ± 3.9 years), 107 patients (110 knees) had IKDC scores, and analysis indicated that although scores in both groups improved from pre- to postoperatively (repair: from 69.5 ± 13.3 to 97.4 ± 4.3; meniscectomy: from 75.7 ± 9.0 to 97.3 ± 3.9; P < .001 for both), improvement in IKDC score was greater after repair (27.9 ± 13.9) versus meniscectomy (21.6 ± 9.4) ( P = .005). Included in the failure analysis were 184 patients (192 knees) at a mean follow-up of 8.4 ± 4.4 years. The rates of reoperation, symptomatic osteoarthritis, and failure were not significantly different between the meniscectomy and repair groups. Conclusion: An increase was seen in the rate of isolated lateral meniscal tear repair in young patients. IKDC score improvement was greater after repair than meniscectomy, although postoperative IKDC scores were similar. Symptomatic arthritis, reoperation, and failure rates were similar between groups; however, there was a trend for increased arthritis symptoms in patients treated with meniscectomy, especially total meniscectomy. Treatment modality, type and location of tear, and amount of meniscus removed were not predictive of final IKDC scores or failure.

Background: Prospective studies evaluating second-look imaging of meniscus root repair using a transtibial pull-out technique are limited; therefore, optimal surgical indications and the technique for meniscus root repair remain uncertain. Hypothesis: It was hypothesized that there would be a high rate of healing, improvement in meniscal extrusion, and prevention of articular cartilage degeneration and subchondral bone abnormalities after meniscus root repair. Study Design: Case series; Level of evidence, 4. Methods: Consecutive patients undergoing transtibial root repair were prospectively enrolled at 2 orthopaedic centers between March 2017 and January 2019. Pre- and postoperative magnetic resonance imaging (MRI) scans were reviewed by a musculoskeletal radiologist in a blinded fashion for meniscal healing, quantification of extrusion, articular cartilage grade, subchondral bone changes, and coronary/meniscotibial ligament abnormalities. Given persistent extrusion observed on postoperative MRI scans, an additional 10 patients gave consent and were enrolled for immediate (before weightbearing) postoperative MRI scans. Results: A total of 45 patients (16 male, 29 female; mean ± standard deviation age, 42.3 ± 12.9 years; body mass index, 31.6) were prospectively enrolled in the study; there were 47 meniscus root repairs: 29 medial and 18 lateral (2 with both). Postoperative MRI was obtained at an average of 6.3 months (range, 5.1-8 months); 98% of meniscal repairs had evidence of healing. Mean extrusion increased significantly, from 1.9 ± 1.5 mm preoperatively to 2.6 ± 1.4 mm postoperatively ( P = .03). There was no significant progression of chondromalacia grade, subchondral edema, insufficiency fracture, subchondral cysts, or subchondral collapse. In the additional 10-patient cohort, the mean preoperative extrusion (1.6 ± 1.2 mm) was not significantly different from that immediately postoperatively (2.0 ± 1.0 mm; P = .23). Conclusion: Prospective MRI analysis of transtibial meniscus root repair confirmed a high rate of meniscal healing and no observable progression of cartilage degeneration or subchondral bone abnormalities at the short-term follow-up. However, meniscal extrusion worsened in the first 6 months after surgery. Registration: NCT03037242 ( ClinicalTrials.gov identifier).

Objectives: Meniscus root tears are increasingly being recognized. Meniscus extrusion has previously been associated with medial root tears; however, the relationship between secondary meniscus restraints, such as the meniscotibial (MT) ligament, extrusion, and root tears has yet to be formally evaluated. The purpose of this study was to better understand the association between MT ligament competence, medial meniscus extrusion, and medial meniscus posterior root tears (MMPRT), as well as to determine the progression of meniscus extrusion over time. Methods: Serial MRI’s from our institution were reviewed for patients who showed evidence of medial meniscus extrusion and MMPRT on at least one of 2+ available MRI’s. All patients were symptomatic at the time of diagnosis. All MRI’s were analyzed independently by two board-certified musculoskeletal radiologists. MT ligament disruption, medial meniscus extrusion, and MMPRT presence was recorded for each MRI. The time between MRI’s, presence of insufficiency fractures, and Outerbridge classification for the medial femur and tibia were also evaluated. Results: 27 knees in 26 patients were included in this study, with a total of 63 MRI’s analyzed (21 knees with 2 MRI’s, 3 with 3 MRI’s, and 3 with 4 MRI’s). All patients demonstrated clear medial meniscus extrusion and meniscotibial ligament disruption prior to the subsequent development of MMPRTs (p < 0.001). Mean extrusion at the time of initial MRI was 3.3 ± 1.1 mm, and increased significantly to 5.5 ± 1.8 mm at the time of first imaging with an identified MMPRT (p < 0.001). The average time between initial MRI and the first identification of MMPRT on a later MRI was 1.7 ± 1.6 years. Conclusions: In a sample of 27 symptomatic knees with serial MRI’s both before and after MMPRT diagnosis, all patients demonstrated MT ligament disruption and associated meniscus extrusion prior to the development of subsequent medial meniscus root tears. These findings suggest that MT ligament disruption and medial meniscus extrusion represent early and predisposing events contributing to MMPRT. Therefore, this provides a possible explanation of why meniscus extrusion is not corrected with medial meniscus root repair.

Purpose To describe double radial tears of the lateral meniscus (LM), report early clinical treatment outcomes, and determine reoperation and failure rates. Methods Twenty‐one (N = 21) consecutive cases of arthroscopic‐treated lateral meniscus double radial tears treated between 2012 and 2018 were reviewed, including 15 males (71.4%) and 6 females (28.6%). Meniscus repairs were all performed at the time of anterior cruciate ligament (ACL) reconstruction. Patients with associated fractures or prior surgeries were excluded. Concomitant injuries were reported, as were preinjury and postoperative Tegner scores, preoperative and postoperative visual analogue pain scale (VAS) scores, and postoperative International Knee Documentation Committee (IKDC) subjective scores. Reoperation and failure rates were documented. Results Twenty‐one (N = 21) tears were located in the posterior horn of the meniscus near the root attachment; 15 (71.4%) underwent all‐inside repair, 4 (19.0%) underwent transtibial pull‐through repair, 1 (4.8%) was partially debrided, and 1 (4.8%) was left untreated. Twenty‐one tears (N = 21) were in the body of the meniscus; 7 (33.3%) were repaired, 7 (33.3%) were partially debrided, and 7 (33.3%) were left untreated. Thirteen patients (62%) had associated medial collateral ligament (MCL) injuries. Mean follow‐up was 2.6 years. VAS at rest and with activity improved by 2.1 points ( P < .001) and 3.1 points ( P = .017) after surgery. The mean postoperative Tegner activity score was 6.4, and the mean IKDC score was 83.2 at final follow‐up. Reoperation was required in 5 patients (23.8%), and the surgical treatment failed in 1 patient (4.7%). Conclusions Double radial tears of the LM are uncommon injuries that occur in the setting of ACL tears, usually combined with MCL injury. The variety of surgical treatment techniques have a low failure rate at short‐term follow‐up. Patients tend to have good clinical outcomes with improvement in pain and overall function after surgically treating these injuries with simultaneous ACL reconstruction. Level of Evidence Level IV, therapeutic study, case series

Abstract The brain vital signs framework is a portable, objective, neurophysiological evaluation of brain function at point-of-care. We investigated brain vital signs at pre- and post-season for age 14 or under (Bantam) and age 16–20 (Junior-A) male ice hockey players to (i) further investigate previously published brain vital sign results showing subconcussive cognitive deficits and (ii) validate these findings through comparison with head-impact data obtained from instrumented accelerometers. With a longitudinal study design, 23 male ice hockey players in Bantam (n = 13; age 13.63 ± 0.62) and Tier II Junior-A (n = 10; age 18.62 ± 0.86) divisions were assessed at pre- and post-season. None were diagnosed with a concussion during the season. Cognitive evoked potential measures of Auditory sensation (N100), Basic attention (P300) and Cognitive processing (N400) were analysed as changes in peak amplitudes and latencies (six standard scores total). A regression analysis examined the relationship between brain vital signs and the number of head impacts received during the study season. Significant pre/post differences in brain vital signs were detected for both groups. Bantam and Junior-A players also differed in number of head impacts (Bantam: 32.92 ± 17.68; Junior-A: 195.00 ± 61.08; P &lt; 0.001). Importantly, the regression model demonstrated a significant linear relationship between changes in brain vital signs and total head impacts received (R = 0.799, P = 0.007), with clear differences between the Bantam and Junior-A groups. In the absence of a clinically diagnosed concussion, the brain vital sign changes appear to have demonstrated the compounding effects of repetitive subconcussive impacts. The findings underscored the importance of an objective physiological measure of brain function along the spectrum of concussive impacts.

ObjectivePatients with meniscal tears reporting meniscal symptoms such as catching or locking have traditionally undergone arthroscopy. The present study was undertaken to investigate whether patients with meniscal tears who report meniscal symptoms have greater improvement with arthroscopic partial meniscectomy (APM) than physical therapy (PT).MethodsWe used data from the Meniscal Tear in Osteoarthritis Research (MeTeOR) trial, which randomized participants with knee osteoarthritis (OA) and meniscal tear to APM or PT. The frequency of each meniscal symptom (clicking, catching, popping, intermittent locking, giving way, swelling) was measured at baseline and 6 months. We used linear regression models to determine whether the difference in improvement in Knee Injury and Osteoarthritis Outcome Score (KOOS) pain score at 6 months between patients treated with APM versus PT was modified by the presence of each meniscal symptom. We also determined the percentage of participants with resolution of meniscal symptoms by treatment group.ResultsWe included 287 participants. The presence (versus absence) of any of the meniscal symptoms did not modify the improvement in KOOS pain score between APM versus PT by >0.5 SD (all P interaction >0.05). APM led to greater resolution of intermittent locking and clicking than PT (locking 70% versus 46%, clicking 41% versus 25%). No difference in resolution of the other meniscal symptoms was observed.ConclusionMeniscal symptoms were not associated with improved pain relief. Although symptoms of clicking and intermittent locking had a greater reduction in the APM group, the presence of meniscal symptoms in isolation should not inform clinical decisions surrounding APM versus PT in patients with meniscal tear and knee OA.

Background: Posterior cruciate ligament (PCL) reconstruction is commonly performed to restore joint stability and prevent posterior tibial translation at higher flexion angles. However, persistent knee laxity after reconstruction is often reported. Purpose: To biomechanically evaluate the effect of independent suture tape (ST) reinforcement on different PCL reconstruction techniques. Study Design: Controlled laboratory study. Methods: PCL reconstruction using porcine bones and quadrupled bovine tendons was performed using 2 techniques: (1) an all-inside method using suspensory adjustable loop devices (ALDs) in the tibia and femur and (2) a method using an interference screw on the tibial and an ALD on the femoral site. Both were tested with and without an additional ST for 4 groups (n = 8 per group). Each construct underwent biomechanical testing involving 3000 loading cycles in 3 stages. After position-controlled cycles simulating full range of motion, force-controlled loading from 10 to 250 N and then from 10 to 500 N were performed before pull-to-failure testing. Elongation, stiffness, and ultimate strength were evaluated. Results: The highest ultimate load (1505 ± 87 N), a small total elongation (2.60 ± 0.97 mm), and stiffness closest to the native human ligament (156.3 ± 16.1 compared with 198.9 ± 33.5 N/mm; P = .192) was seen in the all-inside technique using ST. Intragroup comparison revealed that reinforcement with ST produced a smaller total elongation for the screw fixation (Screw-ALD, 6.06 ± 3.60 vs Screw-ALD ST, 2.50 ± 1.28 mm; P = .018) and all-inside techniques (ALD-ALD, 4.77 ± 1.43 vs ALD-ALD ST, 2.60 ± 0.97 mm; P = .077), albeit the latter was not significantly different. Elongation for constructs without ST increased more rapidly at higher loads compared with elongation for ST constructs. The ultimate strength was significantly increased only for constructs using the all-inside technique using ST (ALD-ALD, 1167 ± 125 vs ALD-ALD ST, 1505 ± 87 N; P = .010). Conclusion: Adding an independent ST to PCL reconstruction led to improvement in the studied metrics by reducing the total elongation and increasing the ultimate strength, independent of the technique used. Clinical Relevance: PCL reconstruction using additional ST reinforcement was biomechanically favorable in this study. ST reinforcement in the clinical setting could decrease knee laxity after PCL reconstruction, providing better joint stability and improved functional outcomes.