Microdrilling Resulted in Less Subchondral Bone Destruction Than a Traditional Microfracture Awl for Articular Cartilage Defect Bone Marrow Stimulation.

Purpose: The purpose of this study was to compare bone marrow stimulation using micro-computed tomography (micro-CT) analysis of an abrasion arthroplasty technique, drilling k-wire technique, traditional microfacture awl, or a microdrill instrument for subchondral bone defects. Methods: Eleven cadaveric distal femoral specimens were obtained and divided into 3 common areas of osteochondral defect: trochlea and weightbearing portions of the medial and lateral femoral condyles. Each area of interest was then denuded of cartilage using a PoweRasp and divided into quadrants. Each quadrant was assigned either a 1.6 mm Kirschner wire (k-wire), 1.25 mm microfracture awl, 1.5 mm fluted microdrill, PowerPick, or a curette (abrasion arthroplasty) to create 4 channels into the subchondral bone sing the same instrument. Subchondral bone and adjacent tissue areas were then evaluated using micro-CT to analyze adjacent bone destruction and extension into the bone marrow. Results: Overall, there was a significantly decreased area of bone destruction or compression using the microdrill (0.030 mm) as compared to the microfracture awl (0.072 mm) and k-wire (0.062 mm) (P < .05). Within the trochlea and the medial femoral condyle, there was significantly decreased bony compression with the microdrill as compared to the awl and k-wire (P < .05); however, when stratified, this was not significant among the lateral femoral condylar samples (P = .08). Conclusion: Bone marrow stimulation causes bony compression that may negatively impact subchondral bone and trabecular alignment. It is important to understand which tools used for bone marrow stimulation cause the least amount of damage to the subchondral bone. Clinical Relevance: This study demonstrates the decreased subchondral bony defects seen with the microdrill versus the traditional microfracture awl indicating that when performing bone marrow stimulation, the microdrill may be a less harmful tool to the subchondral bone.

Early clinical and patient-reported outcomes for arthroscopic and mini-open superior capsular reconstruction are similar for irreparable rotator cuff tears.

OBJECTIVES: The purpose of this study was to report and compare postoperative range of motion (ROM), patient-reported outcomes, and failure rates following superior capsular reconstruction (SCR) and to compare outcomes between arthroscopic and mini-open techniques. METHODS: All SCR procedures utilising dermal allograft with a minimum of 6 months of follow-up at multiple institutions between November 2015 and October 2019 were retrospectively reviewed. Preoperative patient demographics, imaging measurements, surgical technique (arthroscopic versus mini-open), and outcomes including pain scores, conversion to reverse shoulder arthroplasty, subsequent surgery, and postoperative ROM were recorded. Outcomes for arthroscopic versus mini-open approaches were compared via t-test, Fisher's exact test, or chi square test, as appropriate, with differences of p â€‹< â€‹0.05 considered significant. RESULTS: 180 total patients were included, including 98 who underwent arthroscopic SCR and 82 who underwent mini-open SCR. Final follow-up was at a mean of 32 months (standard deviation = 11 months). SCR improved pain (visual analog scale â€‹= â€‹4.4 pre-operatively vs. 1.4 post-operatively, p â€‹< â€‹0.0001) and ROMin active forward flexion (136° pre-operatively vs. 150° post-operatively, p â€‹= â€‹0.0012). No difference in post-operative pain visual analog scores was found between mini-open and arthroscopic cohorts (1.3 vs. 1.6, p â€‹= â€‹0.3432) at a mean of 14 months post-operatively. At a mean of 32 months post-operatively, there were no differences in ASES, QuickDASH, SST, WORC, or SANE scores between open and arthroscopic cohorts. There was no difference in rates of failure between mini-open and arthroscopic cohorts (15.9% vs. 17.3%, p â€‹= â€‹0.789). CONCLUSIONS: This study confirmed that SCR improves pain and ROM in the short term. Mini-open SCR appears to provide similar improvements in pain and ROM compared with arthroscopic SCR, as well as patient-reported outcomes at 3 years. No difference in failure rates was detected between the 2 procedures. LEVEL OF EVIDENCE: Level 3 evidence.

Editorial Commentary: Postoperative Pain Management After Anterior Cruciate Ligament Reconstruction Can Minimize Opioid Use and Allow Early Rehabilitation.

Effective analgesia is essential after anterior cruciate ligament (ACL) reconstruction to control pain while minimizing opioid consumption and allowing early rehabilitation. Orthopaedic surgeons write the third-largest number of opioid prescriptions, which are responsible for 1/10th of all opioid prescriptions, and one-third of patients with ACL injury use opioids preoperatively, a risk factor for postoperative abuse. Pain management after ACL reconstruction using variety of analgesic regimens including various permutations of nerve blocks, nerve block adjuncts, intra-articular injections, intravenous and oral medications, cryotherapy, compression stockings, and transcutaneous electrical nerve stimulation units, based on multidisciplinary collaboration between surgeons and anesthesiologists, can minimize opioid consumption. A recent meta-analysis shows that combined femoral-sciatic nerve block may be a top-ranked analgesic technique. Femoral and adductor canal nerve blocks are also effective alternatives and most common. Femoral and femoral sciatic nerve blocks may risk quadriceps strength deficits, whereas an advantage of adductor canal nerve is that the saphenous nerve is purely sensory. We recommend longer-acting nerve blockade (72 hours) using continuous anesthetic delivery via a pump/catheter with ropivacaine or the use of a slow-release preparation such as bupivacaine liposome injectable suspension.

Isometric Knee Strength is Greater in Individuals Who Score Higher on Psychological Readiness to Return to Sport After Primary Anterior Cruciate Ligament Reconstruction.

Background: Anterior cruciate ligament (ACL) injury is extremely common among athletes. Rate of second ACL injury due to surgical graft rupture or contralateral limb ACL injury is approximately 15-32%. Psychological readiness to return to sport (RTS) may be an important predictor of successful RTS outcomes. Psychological readiness can be quantified using the ACL Return to Sport after Injury (ACL-RSI) questionnaire, with higher scores demonstrating greater psychological readiness. Purpose: The purpose of this study was to investigate differences in functional performance and psychological readiness to return to sport among athletes who have undergone primary ACL reconstruction (ACLR). Study Design: Descriptive cohort study. Methods: Eighteen athletes who had undergone primary ACLR were tested at time of RTS clearance. The cohort was divided into two groups, high score (HS) and low score (LS), based on median ACL-RSI score, and performance on static and dynamic postural stability testing, lower extremity isokinetic and isometric strength testing, and single leg hop testing was compared between the groups using an independent samples t-test. Results: The median ACL-RSI score was 74.17. The average ACL-RSI score was 83.1±6.2 for the HS group and 61.8±8.0 for the LS group. High scorers on the ACL-RSI performed significantly better on isometric knee flexion as measured via handheld dynamometry (22.61% ±6.01 vs. 12.12% ±4.88, p=0.001) than the low score group. Conclusion: The findings suggest that increased knee flexion strength may be important for psychological readiness to RTS after primary ACLR. Further research is indicated to explore this relationship, however, a continued emphasis on improving hamstring strength may be appropriate during rehabilitation following ACLR to positively impact psychological readiness for RTS. Level of Evidence: III.

Females have Lower Knee Strength and Vertical Ground Reaction Forces During Landing than Males Following Anterior Cruciate Ligament Reconstruction at the Time of Return to Sport.

Purpose: There is a high rate of second anterior cruciate ligament (ACL) injury (ipsilateral graft or contralateral ACL) upon return-to-sport (RTS) following ACL reconstruction (ACLR). While a significant amount of epidemiological data exists demonstrating sex differences as risk factors for primary ACL injury, less is known about sex differences as potential risk factors for second ACL injury. The purpose of this study is to determine if there are sex-specific differences in potential risk factors for second ACL injury at the time of clearance for RTS. Methods: Ten male and eight female athletes (age: 20.8 years ±6.3, height: 173.2 cm ±10.1, mass: 76.6 kg ±18.3) participated in the study following ACLR at time of RTS (mean 10.2 months). Performance in lower extremity isokinetic and isometric strength testing, static and dynamic postural stability testing, and a single leg stop-jump task was compared between the sexes. Results: Normalized for body weight, males had significantly greater isokinetic knee flexion (141±14.1 Nm/kg vs. 78±27.4 Nm/kg, p=0.001) and extension strength (216±45.5 Nm/kg vs. 159±53.9 Nm/kg, p=0.013) as well as isometric flexion (21.1±6.87% body weight vs. 12.5±5.57% body weight, p=0.013) and extension (41.1±7.34% body weight vs. 27.3±11.0% body weight, p=0.016) strength compared to females. In the single-leg stop jump task, males had a greater maximum vertical ground reaction force during landing (332±85.5% vs. 259±27.4% body weight, p=0.027) compared to females. Conclusions: Based on these results, there are significant differences between sexes following ACLR at the time of RTS. Lower knee flexion and extension strength may be a potential risk factor for second ACL injury among females. Alternatively, the increased maximum vertical force observed in males may be a potential risk factor of second ACL injury in males. Although these results should be interpreted with some caution, they support that rehabilitation programs in the post-ACLR population should be individualized based on the sex of the individual. Level of Evidence: Level 3.

Operative Versus Nonoperative Management of Displaced Midshaft Clavicle Fractures: A Cost-effectiveness Analysis.

To date, the optimal management of displaced midshaft clavicle fractures remains unknown. Operatively, plate or nail fixation may be used. Nonoperatively, the options are sling or harness. Given the equivocal effectiveness between approaches, the costs to the health care system and the patient become critical considerations. A decision tree model was constructed to study plate and sling management of displaced midshaft clavicle fractures. Primary analysis used 6 randomized controlled trials that directly compared open reduction and internal fixation with a plate to sling. Secondary analysis included 18 studies that studied either plate, sling, or both. Incremental cost-effectiveness ratios (ICERs) were calculated using quality-adjusted life-years (QALYs). Second-order Monte Carlo probabilistic sensitivity analysis (PSA) was subsequently conducted. In primary analysis, at a willingness-to-pay (WTP) threshold of $100,000, operative management was found to be less cost-effective relative to nonoperative management, with an ICER of $606,957/QALY (0.03 additional QALYs gained for an additional $16,120). In PSA, sling management was cost-effective across all WTP ranges. In secondary analysis, the ICER decreased to $75,230/QALY. Primary analysis shows that plate management is not a cost-effective option. In secondary analysis, the incremental effectiveness of plate management increased enough that the calculated ICER is below the WTP threshold of $100,000; however, the strength of evidence in secondary analysis is lower than in primary analysis. Thus, because neither option is dominant in this model, both plate and sling remain viable approaches, although the cost-conscious decision will be to treat these fractures with a sling until future data suggest otherwise. [Orthopedics. 2022;45(5):e243-e251.].

Altered lower extremity biomechanics following anterior cruciate ligament reconstruction during single-leg and double-leg stop-jump tasks: A bilateral total support moment analysis.

BACKGROUND: Injury to the anterior cruciate ligament (ACL) can lead to long-lasting biomechanical alterations that put individuals at risk of a second ACL injury. Examining the total support moment may reveal between- and within-limb compensatory strategies. METHODS: Twenty-six participants who were cleared to return to sport following ACL reconstruction were recruited. Each participant completed the single-leg and double-leg stop jump tasks. These tasks were analyzed using force plates and a 3D motion analysis system. The total support moment was calculated by summing the internal moments of the hip, knee and ankle at peak vertical ground reaction force. FINDINGS: Internal knee extensor moment was lower in the involved limb compared to the uninvolved for both tasks (17.6%, P = 0.022; 18.4%, P = 0.008). No significant between-limb differences were found for the total support moment. The involved limb exhibited an 18.2% decrease in knee joint contribution (P = 0.01) and a 21.6% increase in ankle joint contribution (P = 0.016) to the total support moment compared to the uninvolved limb in the single-leg stop jump task. INTERPRETATION: Compensation for the involved knee is likely due to altered biomechanics that redistributes load to the uninvolved knee or to adjacent joints of the same limb. A partial shift in joint contribution from the knee to the ankle during the single-leg stop jump task demonstrates a tendency to decrease load to the knee. Further studies are needed to investigate how these adaptations impact the prevalence of subsequent injury and poor joint health.

Immune cell profiles in synovial fluid after anterior cruciate ligament and meniscus injuries.

BACKGROUND: Anterior cruciate ligament (ACL) and meniscus tears are common knee injuries. Despite the high rate of post-traumatic osteoarthritis (PTOA) following these injuries, the contributing factors remain unclear. In this study, we characterized the immune cell profiles of normal and injured joints at the time of ACL and meniscal surgeries. METHODS: Twenty-nine patients (14 meniscus-injured and 15 ACL-injured) undergoing ACL and/or meniscus surgery but with a normal contralateral knee were recruited. During surgery, synovial fluid was aspirated from both normal and injured knees. Synovial fluid cells were pelleted, washed, and stained with an antibody cocktail consisting of fluorescent antibodies for cell surface proteins. Analysis of immune cells in the synovial fluid was performed by polychromatic flow cytometry. A broad spectrum immune cell panel was used in the first 10 subjects. Based on these results, a T cell-specific panel was used in the subsequent 19 subjects. RESULTS: Using the broad spectrum immune cell panel, we detected significantly more total viable cells and CD3 T cells in the injured compared to the paired normal knees. In addition, there were significantly more injured knees with T cells above a 500-cell threshold. Within the injured knees, CD4 and CD8 T cells were able to be differentiated into subsets. The frequency of total CD4 T cells was significantly different among injury types, but no statistical differences were detected among CD4 and CD8 T cell subsets by injury type. CONCLUSIONS: Our findings provide foundational data showing that ACL and meniscus injuries induce an immune cell-rich microenvironment that consists primarily of T cells with multiple T helper phenotypes. Future studies investigating the relationship between immune cells and joint degeneration may provide an enhanced understanding of the pathophysiology of PTOA following joint injury.

Histologic Analysis of Porcine Dermal Graft Augmentation in Treatment of Rotator Cuff Tears.

BACKGROUND: Biologic augmentation via extracellular matrix (ECM) scaffolds has been utilized to address rotator cuff tears with poor-quality tissue. PURPOSE: To evaluate the cellular changes in graft explants taken from patients treated with porcine dermal grafts for rotator cuff tears. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Four graft biopsy specimens were obtained from patients treated with porcine dermal grafts in an interposition technique for rotator cuff tears and compared with a nonimplanted graft and a normal rotator cuff specimen. Biopsy of the graft site was performed at 18 days, 3 months, 7 months, and 10.5 months after implantation. Hematoxylin and eosin staining was used to evaluate for cellular and vascular changes. Picrosirius red (PSR) stain with 90° polarized light was performed to evaluate collagen fibril size and orientation. All biopsy specimens were analyzed by a pathologist. RESULTS: There was evidence of progressive remodeling of the porcine dermal grafts. The most mature grafts demonstrated vessel infiltration and extensive remodeling without evidence of inflammation, foreign body reaction, or tissue rejection. PSR demonstrated increased organization of collagen domains, resembling normal tendon by 10.5 months postoperatively. CONCLUSION: This series suggests that ECM grafts may serve as an effective scaffold for host cell infiltration, collagen reorganization, and vascularization as a result of histologic changes demonstrated with retrieval of specimens from patients with rotator cuff tears that were augmented with porcine dermal grafts.

Contracture and transient receptor potential channel upregulation in the anterior glenohumeral joint capsule of patients with end-stage osteoarthritis.

BACKGROUND: During anatomic total shoulder arthroplasty (TSA) for primary glenohumeral osteoarthritis (GHOA), the anterior shoulder joint capsule (ASJC) is characterized grossly by contracture, synovitis, and fibrosis. In tissues that develop fibrosis, there is substantial cross-talk between macrophages, fibroblasts, and myofibroblasts, modulated by calcium signaling and transient receptor potential (TRP) channel signaling. The purpose of this study was to compare and characterize the degree of synovitis, inflammatory infiltrate, and TRP channel expression in ASJC harvested from shoulders with and without primary GHOA. METHODS: The ASJC was resected from patients undergoing TSA for primary GHOA or other diagnoses and compared with ASJC from cadaveric donors with no history of shoulder pathology. ASJC was evaluated by immunohistochemistry to characterize synovial lining and capsular inflammatory cell infiltrate and fibrosis, and to evaluate for expression of TRPA1, TRPV1, and TRPV4, known to be involved in fibrosis in other tissues. Blinded sections were evaluated by 3 graders using a semiquantitative scale; then results were compared between diagnosis groups using nonparametric methods. RESULTS: Compared with normal control, the ASJC in primary GHOA had significantly increased synovitis, fibrosis, mixed inflammatory cell infiltrate including multiple macrophages subsets, and upregulation of TRP channel expression. CONCLUSION: These data support the clinical findings of ASJC and synovial fibrosis in primary GHOA, identify a mixed inflammatory response, and identify dysregulation of TRP channels in the synovium and joint capsule. Further studies will identify the role of synovial and capsular fibrosis early in the development of GHOA.

Rotator Cuff Matrix Augmentation and Interposition: A Systematic Review and Meta-analysis.

BACKGROUND: Surgical management of rotator cuff tears is controversial and complex, ranging from nonoperative management to reverse shoulder arthroplasty. PURPOSE: To systematically review and evaluate the outcomes of graft augmentation or interposition versus rotator cuff repair (RCR) alone and evaluate via meta-analysis whether the use of a graft leads to superior outcomes versus RCR alone. STUDY DESIGN: Systematic review and meta-analysis. METHODS: An electronic literature search (Medline, Embase, CINAHL) was conducted. Studies with a minimum follow-up of 1 year and minimum sample size of 10 that provided clinical results of RCR or rotator cuff reconstruction using any type of augmentation tissue or matrix were included. Methodological quality was evaluated by assessment of the risk of bias in the included studies. Studies comparing outcomes of RCR with graft augmentation or interposition versus repair alone (control group) were subjected to meta-analysis. RESULTS: The authors identified 774 articles and included 36 in the systematic review; 5 of the 36 studies underwent meta-analysis. Except for one outcome measure in a single study, all surgical interventions (RCR alone, RCR with augmentation, and RCR with interposition) improved clinical scores and outcome measures. Because of variability in study outcomes, no graft option was found to be superior. Compared with RCR alone, graft augmentation or interposition provided significantly lower retear rates ( P = .05) and higher American Shoulder and Elbow Surgeons (ASES) scores ( P = .005), but improvements in UCLA (University of California, Los Angeles) scores ( P = .29) and pain scores ( P = .1) did not reach statistical significance. CONCLUSION: In the meta-analysis, graft augmentation or interposition appeared to provide a lower retear rate and improved ASES scores when compared with RCR alone. Future prospective, randomized, controlled, and appropriately powered trials are needed for more definitive recommendations.

Graft use in the treatment of large and massive rotator cuff tears: an overview of techniques and modes of failure with MRI correlation.

Despite technical advances, repair of large or massive rotator cuff tears continues to demonstrate a relatively high rate of failure. Rotator cuff repair or superior capsular reconstruction (SCR) using a variety of commercially available grafts provides a promising option in patients with tears that may be at high risk for failure or otherwise considered irreparable. There are three major graft constructs that exist when utilizing graft in rotator cuff repair or reconstruction: augmentation at the rotator cuff footprint, bridging, and SCR. Each construct has a unique appearance when evaluated using postoperative magnetic resonance imaging (MRI), and each construct has unique sites that are predisposed to failure. Understanding the basic principles of these constructs can help the radiologist better evaluate the postoperative MRI appearance of these increasingly utilized procedures.

Advanced Patellar Tendinopathy Is Associated With Increased Rates of Bone-Patellar Tendon-Bone Autograft Failure at Early Follow-up After Anterior Cruciate Ligament Reconstruction.

BACKGROUND: Revision anterior cruciate ligament (ACL) reconstruction can be potentially devastating for a patient. As such, it is important to identify prognostic factors that place patients at an increased risk for graft failure. There are no data on the effects of patellar tendinopathy on failure of ACL reconstruction when using a bone-patellar tendon-bone (BPTB) autograft. PURPOSE/HYPOTHESIS: The purpose of this study was to investigate the association of patellar tendinopathy with the risk of graft failure in primary ACL reconstruction when using a BPTB autograft. The hypothesis was that patellar tendinopathy would result in higher rates of graft failure when using a BPTB autograft for primary ACL reconstruction. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: All patients undergoing ACL reconstruction at a single institution from 2005 to 2015 were examined. A total of 168 patients undergoing primary ACL reconstruction with a BPTB autograft were identified. Patients' magnetic resonance imaging scans were reviewed for the presence and grade of patellar tendinopathy by 2 musculoskeletal fellowship-trained radiologists; both were blinded to the aim of the study, patient demographics, surgical details, and outcomes. Patients were divided into 2 groups: failure (defined as presence of symptomatic laxity or graft insufficiency) and success of the ACL graft. Statistical analyses were run to examine the association of patellar tendinopathy with failure of ACL reconstruction using a BPTB autograft. RESULTS: At a mean follow-up of 18 months, there were 7 (4.2%) patients with graft failure. Moderate or severe patellar tendinopathy was associated with ACL graft failure (P = .011). Age, sex, and side of reconstruction were not associated with the risk of graft failure, although the majority of patients who failed were younger than 20 years. The use of patellar tendons with moderate to severe tendinopathy was associated with a relative risk of ruptures of 6.1 (95% CI, 1.37-27.34) as compared with autograft tendons without tendinopathy. CONCLUSION: Moderate or severe patellar tendinopathy significantly increases the risk of graft failure when using a BPTB autograft for primary ACL reconstruction. Patellar tendinopathy should be considered when determining the optimal graft choice for patients undergoing primary ACL reconstruction with autograft tendons.

How to Use a Graft in Irreparable Rotator Cuff Tears: A Literature Review Update of Interposition and Superior Capsule Reconstruction Techniques.

PURPOSE OF REVIEW: To introduce the challenges in addressing irreparable rotator cuff tears and examine the surgical options, specifically interposition grafting and superior capsule reconstruction. RECENT FINDINGS: Interposition grafting of rotator cuff tears shows promising results in reducing pain and improving function postoperatively and one study demonstrated that it performs significantly better than partial repair alone. Superior capsule reconstruction has become popular rapidly, but given the novelty of the procedure, there is currently a paucity of outcomes data to review. Irreparable rotator cuff tears are a challenging condition with a variety of surgical options available. Two such options-interposition and superior capsule reconstruction-both employ grafts in an attempt to restore joint stability and function. In the past 3 years, literature discussing interposition grafting has explored the different types of grafts, and mostly employed pre-post analysis. The recent superior capsule reconstruction articles strictly used human dermal allograft and offer a variety of surgical techniques without quantitative data.

Interposition Dermal Matrix Xenografts: A Successful Alternative to Traditional Treatment of Massive Rotator Cuff Tears.

BACKGROUND: Management of massive rotator cuff tears in shoulders without glenohumeral arthritis remains problematic for surgeons. Repairs of massive rotator cuff tears have failure rates of 20% to 94% at 1 to 2 years postoperatively as demonstrated with arthrography, ultrasound, and magnetic resonance imaging. Additionally, inconsistent outcomes have been reported with debridement alone of massive rotator cuff tears, and limitations have been seen with other current methods of operative intervention, including arthroplasty and tendon transfers. HYPOTHESIS: The use of interposition porcine acellular dermal matrix xenograft in patients with massive rotator cuff tears will result in improved subjective outcomes, postoperative pain, function, range of motion, and strength. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Sixty patients (61 shoulders) were prospectively observed for a mean of 50.3 months (range, 24-63 months) after repair of massive rotator cuff tears with porcine acellular dermal matrix xenograft as an interposition graft. Subjective outcome data were obtained with visual analog scale for pain score (0-10, 0 = no pain) and Modified American Shoulder and Elbow Surgeons (MASES) score. Active range of motion in flexion, external rotation, and internal rotation were recorded. Strength in the supraspinatus and infraspinatus muscles was assessed manually on a 10-point scale and by handheld dynamometer. Ultrasound was used to assess the integrity of the repair during latest follow-up. RESULTS: Mean visual analog scale pain score decreased from 4.0 preoperatively to 1.0 postoperatively ( P < .001). Mean active forward flexion improved from 140.7° to 160.4° ( P < .001), external rotation at 0° of abduction from 55.6° to 70.1° ( P = .001), and internal rotation at 90° of abduction from 52.0° to 76.2° ( P < .001). Supraspinatus manual strength increased from 7.7 to 8.8 ( P < .001) and infraspinatus manual strength from 7.7 to 9.3 ( P < .001). Mean dynamometric strength in forward flexion was 77.7 N in nonoperative shoulders (shoulder that did not undergo surgery) and 67.8 N ( P < .001) in operative shoulders (shoulder that underwent rotator cuff repair with interposition porcine dermal matrix xenograft). Mean dynamometric strength in external rotation was 54.5 N in nonoperative shoulders and 50.1 N in operative shoulders ( P = .04). Average postoperative MASES score was 87.8. Musculoskeletal ultrasound showed that 91.8% (56 of 61) of repairs were fully intact; 3.3% (2 of 61), partially intact; and 4.9% (3 of 61), not intact. CONCLUSION: Patients who underwent repair of massive rotator cuff tears with interposition porcine acellular dermal matrix graft have good subjective function as assessed by the MASES score. Patients have significant improvement in pain, range of motion, and manual muscle strength. Postoperative ultrasound demonstrated that the repair was completely intact in 91.8% of patients, a vast improvement compared with results previously reported for primary repairs of massive rotator cuff tears.

Posterolateral portal tibial tunnel drilling for posterior cruciate ligament reconstruction: technique and evaluation of safety and tunnel position.

PURPOSE: To evaluate the safety for neurovascular structures and accuracy for tunnel placement of the posterolateral portal tibial tunnel drilling technique in posterior cruciate ligament (PCL) reconstruction. METHODS: Fifteen fresh-frozen human cadaveric knees were used. The tibial tunnel for the PCL was created using a flexible reamer from the posterolateral portal. Then, the flexible pin was left in place, and the distance from the posterolateral portal, the flexible pin, and the tibial tunnel to the peroneal nerve and popliteal artery was measured. Additionally, the distance between the tibial tunnel and several landmarks related to the PCL footprint was measured, along with the distance from the exit point of the flexible pin to the superficial medial collateral ligament and gracilis tendon. RESULTS: The peroneal nerve and the popliteal neurovascular bundle were not damaged in any of the specimens. The median (range) distance in mm from the peroneal nerve and popliteal artery to the posterolateral portal and flexible pin was: 52 (40-80) and 50 (40-61), and 35 (26-51) and 22 (16-32), respectively. The median (range) distance from the tibial tunnel to the popliteal artery was 21 mm (15-38). The tibial tunnel was located at a median (range) distance in mm of 3 (2-6), 6 (3-12), 5 (2-7), 4 (1-8), 9 (3-10), 10 (4-19), and 19 (6-24) to the champagne-glass drop-off, lateral cartilage point, shiny white fibre point, medial groove, medial meniscus posterior root, lateral meniscus posterior root, and posterior aspect of the anterior cruciate ligament, respectively. CONCLUSIONS: The posterolateral portal tibial tunnel technique is safe relative to neurovascular structures and creates an anatomically appropriate tibial tunnel location. The clinical relevance of study is that this technique may be safely and accurately used in PCL reconstruction to decrease the risk of neurovascular damage (avoid use of a posteriorly directed pin), avoid the use of intraoperative fluoroscopy, and avoid the sharp turn during graft passage.

A prospective, multicenter study to evaluate clinical and radiographic outcomes in primary rotator cuff repair reinforced with a xenograft dermal matrix.

BACKGROUND: Minimal information is currently available on the outcome of rotator cuff repair reinforced with an extracellular matrix (ECM) graft. Therefore, the purpose of this study was to determine the clinical and radiographic outcome of repair of large rotator cuff tears with ECM graft reinforcement. METHODS: This was a prospective study of 61 shoulders with large repairable rotator cuff tears (3 to 5 cm). The rotator cuff tears were surgically repaired and reinforced with a xenograft ECM graft. The average patient age was 56 years (range, 40-69 years). The average tear size was 3.8 cm. RESULTS: Follow-up was obtained at 6, 12, and 24 months in 58, 54, and 50 of the 61 patients, respectively. Functional outcome scores, isometric muscle strength, and active range of motion were significantly improved compared with baseline. Magnetic resonance imaging at 12 months showed retorn rotator cuff repairs in 33.9% of shoulders, using the criteria of a tear of at least 1 cm, and tears in 14.5% of the shoulders using the criteria of retear >80% of the original tear size. Three patients underwent surgical revision. Complications included 1 deep infection. CONCLUSIONS: Repair of large rotator cuff tears structurally reinforced with xenograft ECM resulted in improved functional outcomes scores and strength. Adverse events were uncommon, and the rate of revision surgery was low.

Inside-Out or Outside-In Suturing Should Not Be Considered the Standard Repair Method for Radial Tears of the Midbody of the Lateral Meniscus: A Systematic Review and Meta-Analysis of Biomechanical Studies.

The purpose was to evaluate which meniscal repair technique for radial tears of the midbody of the lateral meniscus demonstrates the best biomechanical properties. An electronic literature search was conducted using PubMed, EMBASE, CINAHL, and ScienceDirect databases. Biomechanical studies investigating the repair characteristics of radial tears in the midbody of the lateral meniscus were included. After appropriate screening, a total of 54 studies were reviewed in detail (full text), and 6 met inclusion criteria. The most common cause of exclusion was the investigation of longitudinal tears. Only two studies could be meta-analyzed. Stiffness was significantly higher for all-inside compared with inside-out repair techniques (p = 0.0009). No significant differences were observed between both suture methods for load to failure (p = 0.45). However, both studies used different all-inside devices and suture constructs. No clear conclusions can be drawn from the comparison of both types of repairs for displacement, site of failure, or contact pressure changes. Overall, there are no conclusive data to suggest that inside-out or outside-in suture repair has better load to failure or stiffness, less displacement, or different site of failure compared with all-inside repair. According to biomechanical data, it is under surgeon's preference to elect one repair technique over the other.

Knee Kinematics During Noncontact Anterior Cruciate Ligament Injury as Determined From Bone Bruise Location.

BACKGROUND: The motions causing noncontact anterior cruciate ligament (ACL) injury remain unclear. Tibiofemoral bone bruises are believed to be the result of joint impact near the time of ACL rupture. The locations and frequencies of these bone bruises have been reported, but there are limited data quantifying knee position and orientation near the time of injury based on these contusions. HYPOTHESIS: Knee position and orientation near the time of noncontact ACL injury include extension and anterior tibial translation. STUDY DESIGN: Descriptive laboratory study. METHODS: Magnetic resonance images of 8 subjects with noncontact ACL injuries were acquired within 1 month of injury and were subsequently analyzed. All subjects exhibited bruises on both the femur and tibia in both medial and lateral compartments. The outer margins of bone and the bone bruise surfaces were outlined on each image to create a 3-dimensional model of each subject's knee in its position during magnetic resonance imaging (MRI position). Numerical optimization was used to maximize overlap of the bone bruises on the femur and tibia and to predict the position of injury. Flexion angle, valgus orientation, internal tibial rotation, and anterior tibial translation were measured in both the MRI position and the predicted position of injury. Differences in kinematics between the MRI position, which served as an unloaded reference, and the predicted position of injury were compared by use of paired t tests. RESULTS: Flexion angle was near full extension in both the MRI position and the predicted position of injury (8° vs 12°; P = .2). Statistically significant increases in valgus orientation (5°; P = .003), internal tibial rotation (15°; P = .003), and anterior tibial translation (22 mm; P < .001) were observed in the predicted position of injury relative to the MRI position. CONCLUSION: These results suggest that for the bone bruise pattern studied, landing on an extended knee is a high risk for ACL injury. Extension was accompanied by increased anterior tibial translation (22 mm), internal tibial rotation (15°), and valgus rotation (5°) in the predicted position of injury relative to the MRI position. CLINICAL RELEVANCE: This study provides novel data characterizing the motions associated with ACL injury, information critical to improving strategies aimed at injury prevention.