Citations

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.

Objectives: There is a paucity of literature regarding outcomes of anterior shoulder instability (ASI) in throwers and overhead athletes (OHA). The purpose of this study was to report the pathology, treatment strategies, and outcomes of ASI in throwers and overhead athletes utilizing an established US geographic population-based cohort. Methods: An established geographic database of more than 500,000 patients was used to identify athletes <40 years of age with ASI between 1994 and 2016. Medical records were reviewed to obtain demographics, type of sport, surgical details, and clinical outcomes. Patients were contacted after final clinical follow-up for patient reported outcomes (PRO). The Western Ontario Shoulder Instability (WOSI) score, return to sport at previous level of performance (RPP), rate of return to play (RTP) and time to RTP were recorded. Statistical analysis was performed comparing throwers to non-throwers and OHA to non-overhead athletes (NOHA). Results: The study population consisted of 171 patients, 114 NOHA and 57 OHA. Of the OHA, 40 were throwers. The mean follow-up was 14.7 ± 5.6 years for PRO’s and 11.7 ± 7.3 years for last clinical evaluation. No difference in overall instability events was seen in either group. Throwers were more likely to present with subluxations while non-throwers were more likely to present with frank dislocations. NOHA and non-throwers were more likely than OHA and throwers to have a history of trauma related to ASI, respectively ( P = <.001, P = .002). Throwers were more likely to undergo an open surgical procedure (45%) than non-throwers (15%) ( P = .038). The rate of recurrent instability between groups was similar. Throwers returned to sport at a lower rate than non-throwers, however this did not reach significance (64% vs 83%, P = .100). Throwers and OHA reported similar WOSI scores, RPP and time to RTP grouped by surgical or conservative management compared to non-throwers and NOHA, respectively. Conclusions: In a US cohort of patients, throwers and OHA had a similar number of instability events compared to non-throwers and NOHA, respectively. Non-throwers and NOHA were more likely to present with frank dislocation which is supported by the significantly higher rates of trauma in both groups. Notably, the WOSI score, RPP, rate of RTP and time to RTP showed no difference between throwers and OHA when compared to their non-throwing and NOHA counterparts.

Objectives: The current literature lacks evidence to guide treatment of isolated lateral meniscus tears in young patients. Accordingly, the purpose of this study was to describe our institutional experience in young patients with lateral meniscus tear with regard to i) treatment trends in meniscectomy and repair ii) long-term patient reported and radiographic outcomes, and iii) failure rates and associated patient and treatment factors. Methods: Patients <26 years of age who underwent surgery for lateral meniscus tears between 2001 and 2017. Patients with ligamentous injury or prior surgeries in the same knee were excluded. Records were reviewed to obtain patient demographics, injury characteristics, surgical details, reoperation rates, repeat imaging, and patient outcome scores. Statistical analysis compared treatment trends over time. Patient reported outcomes (PROs), imaging outcomes, and failure rates were compared by treatment modality. Failure was defined as reoperation, symptomatic osteoarthritis, or IKDC <75. Simple logistic regressions were calculated to predict failure and IKDC based on treatment, type of tear, location of tear, or amount of meniscus removed. Results: 226 knees in 217 patients were identified with average clinical follow-up of 3.2 years. Our cohort consisted of 158 male patients, and average age was 17.4 years (7-25). 138 patients (144 knees) were treated with meniscectomy (partial to complete) (64%) and 79 patients (82 knees) were treated with repair (36%). Repair rates compared to meniscectomy (any degree) increased over time with 63% of lateral meniscus tears from 2013-2017 treated with repair compared to 23% from 2001 -2004 ( P = <.0001). IKDC scores in the meniscectomy group increased from 76.3 ± 9.1 pre-operatively to 97.2 ± 3.9 post-operatively ( P = <.0001) and increased in the repair group from 71.0 ± 11.5 pre-operatively to 97.4 ± 4.1 post-operatively ( P = <.0001).The change in IKDC score was greater in repair (26.0 ± 12.3) than meniscectomy (21.1 ± 9.8) ( P = .002). Reoperation rates in meniscectomy (20%) and repair (20%) were similar ( P = .910). Pre-operative IKDC scores were lower in the repair group ( P = .001), but final IKDC scores were similar ( P = 0.695). Symptomatic OA was noted in 17 patients in the meniscectomy group (22%) and 5 patients in the repair group (11%) ( P = .121). The failure rate was similar between meniscectomy (35%) and repair (28%) ( P = .307). Regression equations evaluating treatment modality, type and location of tear, and amount of meniscus removed did not reach significance in predicting IKDC or failure. Conclusions: In this cohort of young patients with isolated lateral meniscus tears, rate of repair increased over time. IKDC scores improved more in the repair group compared to the meniscectomy patients, however IKDC scores obtained at final follow-up were similar. Rates of symptomatic OA, reoperation, and failure were similar between groups. Treatment modality, type and location of tear, and amount of meniscus removed were not predictive of final IKDC or failure.

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 allograft transplant (MAT) is an important treatment option for young patients with deficient menisci; however, there is a lack of consensus on the optimal method of allograft fixation. Hypothesis: The various methods of MAT fixation have measurable and significant differences in outcomes. Study Design: Meta-analysis; Level of evidence, 4. Methods: A single-arm meta-analysis of studies reporting graft failure, reoperations, and other clinical outcomes after MAT was performed. Studies were stratified by suture-only, bone plug, and bone bridge fixation methods. Proportionate rates of failure and reoperation for each fixation technique were pooled with a mixed-effects model, after which reconstruction of relative risks with confidence intervals was performed using the Katz logarithmic method. Results: A total of 2604 patients underwent MAT. Weighted mean follow-up was 4.3 years (95% CI, 3.2-5.6 years). During this follow-up period, graft failure rates were 6.2% (95% CI, 3.2%-11.6%) for bone plug fixation, 6.9% (95% CI, 4.5%-10.3%) for suture-only fixation, and 9.3% (95% CI, 6.2%-13.9%) for bone bridge fixation. Transplanted menisci secured using bone plugs displayed a lower risk of failure compared with menisci secured via bone bridges (RR = 0.97; 95% CI, 0.94-0.99; P = .02). Risks of failure were not significantly different when comparing suture fixation to bone bridge (RR = 1.02; 95% CI, 0.99-1.06; P = .12) and bone plugs (RR = 0.99; 95% CI, 0.96-1.02; P = .64). Allografts secured using bone plugs were at a lower risk of requiring reoperations compared with those secured using sutures (RR = 0.91; 95% CI, 0.87-0.95; P < .001), whereas allografts secured using bone bridges had a higher risk of reoperation when compared with those secured using either sutures (RR = 1.28; 95% CI, 1.19-1.38; P < .001) or bone plugs (RR = 1.41; 95% CI, 1.32-1.51; P < .001). Improvements in Lysholm and International Knee Documentation Committee scores were comparable among the different groups. Conclusion: This meta-analysis demonstrates that bone plug fixation of transplanted meniscal allografts carries a lower risk of failure than the bone bridge method and has a lower risk of requiring subsequent operations than both suture-only and bone bridge methods of fixation. This suggests that the technique used in the fixation of a transplanted meniscal allograft is an important factor in the clinical outcomes of patients receiving MATs.

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).

Abstract Articular cartilage defects are common and can result in substantial pain and disability, prompting operative intervention, which commonly includes chondral debridement. Controlled defect preparation up to but not beyond the calcified cartilage layer is key to clinical success, but this remains technically challenging. We present a technique highlighting the substantial decrease in curette stroke volume and associated shift to a lower pitch when achieving satisfactory open cartilage defect debridement. These audiologic cues correlate well with histologic accuracy of debridement. Therefore, quantifiable pitch and volume changes serve as valuable technical cues for precise defect preparation at the time of joint preservation surgery. Classifications I: knee, II: cartilage. Technique Video video See video under supplementary data.

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.