Epidemiology of Stingers in the National Football League, 2015-2019

BACKGROUND

Transient traumatic neuropraxia of either the brachial plexus or cervical nerve root(s) is commonly described as a "stinger" or "burner" by the athlete. Stingers in American Football commonly occur acutely as isolated injuries; however, concomitant injuries, including cervical spine pathologies, have also been reported.

HYPOTHESIS

Among National Football League (NFL) athletes, the incidence rate of stingers is higher during the regular season than during the preseason and among positions with high velocity impacts such as running backs, linebackers, defensive backs, and receivers.

STUDY DESIGN

Retrospective epidemiology study.

LEVEL OF EVIDENCE

Level 4.

METHODS

Aggregation of all in-game injuries with a clinical impression of "neck brachial plexus stretch" or "neck brachial plexus compression" entered into the NFL injury surveillance database through the centralized league-wide electronic medical record system over 5 years (2015-2019 seasons). Incidence rates per player-play were calculated and reported.

RESULTS

A total of 691 in-game stingers occurred during the study period, with a mean of 138.2 per year. Average single-season injury risk for incident stinger was 3.74% (95% CI, 3.46%-4.05%). The incidence rate was higher during regular season games than during preseason games (12.26 per 100,000 player-plays [11.30-13.31] vs 8.87 [7.31-10.76], P < 0.01, respectively). The highest reported stinger incidence rates were among running backs and linebackers (both >15 per 100,000 player-plays). Among stingers, 76.41% did not miss time. Of those that resulted in time lost from football activities, mean time missed due to injury was 4.79 days (range, 3.17-6.41 days). Concomitant injuries were relatively low (7.09%).

CONCLUSION

In-game stinger incidence was stable across the study period and occurred most frequently in running backs and linebackers. Stingers were more common during the regular season, and most players did not miss time. Concomitant injuries were relatively rare.

CLINICAL RELEVANCE

An improved understanding of the expected time loss due to stinger and concomitant injuries may provide insight for medical personnel in managing these injuries.

Tape-Reinforced Graft Suturing and Retensioning of Adjustable-Loop Cortical Buttons Improve Quadriceps Tendon Autograft Biomechanics in Anterior Cruciate Ligament Reconstruction: A Cadaveric Study

PURPOSE

To investigate the biomechanical effects of tape-reinforced graft suturing and graft retensioning for all-soft tissue quadriceps tendon (ASTQT) anterior cruciate ligament reconstruction (ACLR) in a full-construct human cadaveric model.

METHODS

Harvested cadaveric ASTQT grafts were assigned to either (1) double-suspensory adjustable-loop cortical button device (ALD) fixation in which both graft ends were fixed with a suspensory fixation device with (n = 5) or without (n = 5) tape-reinforced suturing or (2) single-suspensory distal tendon fixation in which only the patellar end was fixed with an ALD (n = 5) or fixed-loop cortical button device (FLD) (n = 5). All specimens were prepared using a No. 2 whipstitch technique, and tape-reinforced specimens had an integrated braided tape implant. Graft preparation time was recorded for double-suspensory constructs. Samples were tested on an electromechanical testing machine using a previously published protocol simulating rehabilitative kinematics and loading.

RESULTS

Tape-reinforced graft suturing resulted in greater graft load retention after cycling (11.9% difference, P = .021), less total elongation (mean [95% confidence interval (CI)], 5.57 mm [3.50-7.65 mm] vs 32.14 mm [25.38-38.90 mm]; P < .001), greater ultimate failure stiffness (mean [95% CI], 171.9 N/mm [158.8-185.0 N/mm] vs 119.4 N/mm [108.7-130.0 N/mm]; P < .001), and less graft preparation time (36.4% difference, P < .001) when compared with unreinforced specimens. Retensioned ALD constructs had less cyclic elongation compared with FLD constructs (mean total elongation [95% CI], 7.04 mm [5.47-8.61 mm] vs 12.96 mm [8.67-17.26 mm]; P = .004).

CONCLUSIONS

Tape-reinforced graft suturing improves time-zero ASTQT ACLR construct biomechanics in a cadaveric model with 83% less total elongation, 44% greater stiffness, and reduced preparation time compared with a whipstitched graft without tape reinforcement. ALD fixation improves construct mechanics when compared with FLD fixation as evidenced by 46% less total elongation.

CLINICAL RELEVANCE

Tape-reinforced implants and graft retensioning using ALDs improve time-zero ACLR graft construct biomechanics in a time-zero biomechanical model. Clinical studies will be necessary to determine whether these implants improve clinical outcomes including knee laxity and the incidence of graft rupture.

Suture Augmentation of a Four-Strand Semitendinosus Graft Improves Time-Zero Biomechanical Properties

PURPOSE

To compare the time-zero biomechanical properties of hamstring graft preparations with or without suture augmentation for anterior cruciate ligament reconstruction (ACLR) in a full-construct cadaveric model.

METHODS

Hamstring grafts were harvested from 24 fresh frozen human cadavers and prepared in 1 of 3 ways: quadrupled SemiTendinosus (SemiT), and quadrupled SemiT with suture augmentation (SemiT+2.0-mm tape or SemiT+1.3-mm tape; n = 8 per group). Adjustable loop suspensory implants and cortical buttons were used for fixation on a porcine tibia and acrylic block. Testing included force-controlled cyclic loading at 250 N and 400 N followed by load to failure.

RESULTS

The 2 suture augmentation groups had less total elongation and increased stiffness compared to the nonsuture-augmented group (P = .025). The SemiT+2.0-mm tape group had 36% less total elongation and 34% increased stiffness compared to SemiT+1.3mm tape (P < .001).

CONCLUSIONS

Suture augmentation improves construct biomechanics at time zero following hamstring tendon ACLR. Augmentation with 2.0-mm tape suture improves construct biomechanics compared to 1.3-mm tape suture.

CLINICAL RELEVANCE

Independent suture augmentation of a quadrupled SemiT graft improves ACLR construct biomechanics. Outcomes were improved with augmentation using 2.0-mm tape suture compared to 1.3-mm tape suture.

Arthroscopic-Assisted Lateral Extra-Articular Tenodesis With Knotless Anchor Fixation

Recent studies have reported the biomechanical and clinical advantages of lateral extraarticular augmentation procedures including the modified lateral extra-articular tenodesis (LET) in the setting of anterior cruciate ligament reconstruction. LET has been shown to significantly decrease re-rupture rates in high-risk patients and decrease anterior cruciate ligament graft forces during pivoting loads and instrumented anterior laxity testing. Many variations of the modified LET approaches have been described. However, concerns including lateral hematoma, wound-healing complications, and increased operative time exist. This minimally invasive, arthroscopic-assisted approach using a knotless, all-suture anchor allows for direct visualization through a 2-cm incision and inherently decreases the morbidity associated with traditional LET techniques.

Standardized Opioid Counseling Is Underperformed Before and After Anterior Cruciate Ligament Reconstruction

PURPOSE

To characterize contemporary pain management strategies after anterior cruciate ligament reconstruction (ACLR) within the US and international orthopaedic community.

METHODS

This was a cross-sectional survey-based study disseminated to a consortium of expert orthopaedic surgeons in the management of anterior cruciate ligament injuries. The survey was a 27-question, multiple choice-style questionnaire with question topics ranging from demographic characteristics and practice characteristics to surgeon-specific pain management strategies in the postoperative period after ACLR. Specific topics of interest included the use of preoperative opioid education and/or counseling sessions, implementation of standardized pain management regimens, use of pain tracking systems, and use of any adjunct non-narcotic analgesic modalities.

RESULTS

A total of 34 completed surveys were collected, representing a 73.9% response rate. Over 85% of respondents reported prescribing opioids as a standardized postoperative regimen after ACLR. Surgeons reported prescribing 5- to 10-mg doses, with the tablet count ranging anywhere from fewer than 10 tablets to more than 20 tablets, often instructing their patients to stop opioid use 2 to 4 days postoperatively. Prescribed dosages remained stable or decreased over the past 6 months with increased use of non-narcotic adjuncts. Only one-third of respondents reported using standardized preoperative opioid counseling, with even fewer discussing postoperative discontinuation protocols.

CONCLUSIONS

Over 85% of respondents prescribe opioids as a standardized postoperative regimen after ACLR, with only 15% providing non-narcotic pain regimens. However, prescribed dosages have remained stable or decreased over the past 6 months with increased use of non-narcotic adjuncts. Only one-third of respondents use standardized preoperative opioid counseling, with even fewer discussing postoperative discontinuation protocols.

CLINICAL RELEVANCE

The ongoing opioid epidemic has created an urgent need to identify the most effective pain management strategies after orthopaedic procedures, especially ACLR. This study provides important information about current pain management practices for patients who have undergone ACLR.

Allograft Anterior Cruciate Ligament Reconstruction Fails at a Greater Rate in Patients Younger Than 34 Years

Purpose

To characterize the secondary anterior cruciate ligament (ACL) injury rates after primary allograft anterior cruciate ligament reconstruction (ACLR) and to identify the age cut-score at which the risk of allograft failure decreases.

Methods

All patients who underwent primary ACLR within a single orthopaedic department between January 2005 and April 2020 were contacted at a minimum of 2 years post-ACLR to complete a survey regarding complications experienced post-surgery, activity level, and perceptions of knee health. Patients were excluded for incidence of previous ACLR (ipsilateral or contralateral) and/or age younger than 14 years. Relative proportions were calculated, binary regression analysis was performed, and receiver operating characteristic analysis was used to identify the threshold age for maximal sensitivity and specificity to predict high risk of allograft failure, defined as undergoing revision ACLR.

Results

Of the 939 surveys completed, 398 patients underwent primary allograft ACLR (mean age 39.5 years; range 16.0-66.1 years; 54.3% female). The secondary ACL injury rate was 11.6% (5.8% ipsilateral revision ACLR, 5.8% contralateral ACL injury). Male and female patients had similar revision (5.5% male, 6.0% female, P = .82) and contralateral ACL injury rates (6.6% male, 5.1% female, P = .52). Receiver operating characteristic analysis indicated that age ≤34 years was threshold for differentiating high risk of allograft failure (area under the curve 0.65, 95% confidence interval 0.55-0.76; P = .014). Patients aged ≤34 years had a greater secondary injury rate than patients >34 years (20.4% (10.2% revision ACLR, 10.2% contralateral ACL injury) versus 6.9% (3.5% revision ACLR, 3.5% contralateral ACL injury; P < .001). Binary regression analysis demonstrated that decreasing age was associated with increased risk of graft failure (χ2 = 7.9, P = .02.).

Conclusions

Allograft ACLR showed similar failure rates between sexes but displayed suboptimal graft failure outcomes in younger and active patients. By age 34 years, the increased revision risk for younger patients diminished.

Level of Evidence

Level IV, therapeutic case series.

Complete Restoration of Native Glenoid Width Improves Glenohumeral Biomechanics After Simulated Latarjet

BACKGROUND

The amount of glenoid width that must be restored with a Latarjet procedure in order to reestablish glenohumeral stability has not been determined.

PURPOSE/HYPOTHESIS

The purpose of this article was to determine the percentage of glenoid width restoration necessary for glenohumeral stability after Latarjet by measuring anterior humeral head translation and force distribution on the coracoid graft. The hypothesis was that at least 100% of glenoid width restoration with Latarjet would be required to maintain glenohumeral stability.

STUDY DESIGN

Controlled laboratory study.

METHODS

Nine cadaveric shoulders were prepared and mounted on an established shoulder simulator. A lesser tuberosity osteotomy (LTO) was performed to allow accurate removal of glenoid bone. Coracoid osteotomy was performed, and the coracoid graft was sized to a depth of 10 mm. Glenoid bone was sequentially removed, and Latarjet was performed using 2 screws to reestablish 110%, 100%, 90%, and 80% of native glenoid width. The graft was passed through a subscapularis muscle split, and the LTO was repaired. A motion tracking system recorded glenohumeral translations, and force distribution was recorded using a TekScan pressure sensor secured to the glenoid face and coracoid graft. Testing conditions included native; LTO; Bankart tear; and 110%, 100%, 90%, and 80% of glenoid width restoration with Latarjet. Glenohumeral translations were recorded while applying an anteroinferior load of 44 N at 90° of humerothoracic abduction and 0° or 45° of glenohumeral external rotation. Force distribution was recorded without an anteroinferior load.

RESULTS

Anterior humeral head translation progressively increased as the proportion of glenoid width restored decreased. A marked increase in anterior humeral head translation was found with 90% versus 100% glenoid width restoration (10.8 ± 3.0 vs 4.1 ± 2.6 mm, respectively; P < .001). Greater glenoid bone loss also led to increased force on the coracoid graft relative to the native glenoid bone after Latarjet. A pronounced increase in force on the coracoid graft was seen with 90% versus 100% glenoid width restoration (P < .001).

CONCLUSION

Anterior humeral head translation and force distribution on the coracoid graft dramatically increased when <100% of the native glenoid width was restored with a Latarjet procedure.

CLINICAL RELEVANCE

If a Latarjet is unable to fully restore the native glenoid width, surgeons should consider alternative graft sources to minimize the risk of recurrent instability or coracoid overload.

Trends and Projections in Surgical Stabilization of Glenohumeral Instability in the United States from 2009 to 2030: Rise of the Latarjet and Fall of the Open Bankart

INTRODUCTION

Advances in surgical techniques have improved the ability to address recurrent glenohumeral instability via arthroscopic capsulolabral repair and bone restoring procedures such as Latarjet. Given the paucity of studies analyzing temporal trends in surgical management of glenohumeral instability, the purpose of this study was to assess trends in treatment of anterior, posterior, and multidirectional instability over a 10-year period and model projections to 2030.

METHODS

Using IBM Watson Marketscan national database, all patients that underwent glenohumeral instability procedures from 2009 to 2018 were identified. Procedures were identified using common procedural terminology (CPT) codes for open Bankart Repair, Latarjet, anterior bone block, posterior bone block, multidirectional capsular shift, and arthroscopic Bankart procedures. Sample weights provided by the database were utilized to calculate national estimates. The United States (U.S.) Census Bureau annual population data were utilized for calculating incidence. Future projections to 2030 were modeled using Poisson and linear regression.

RESULTS

There were an estimated 446,072 glenohumeral instability cases from 2009-2018. Per capita (per 100,000) incidence remained constant, from 14.8 in 2009 to 14.5 in 2018. Arthroscopic Bankart comprised the highest number of procedures throughout the study period, accounting for 89% of all procedures in 2009 and 93% in 2018. Open Bankart procedures decreased by 65% from 2009 to 2018, while there was a 250% increase in Latarjet procedures over the same period. Patient demographics did not change over the study period, and males aged 18-25 comprised the largest demographic group undergoing anterior instability procedures. Multidirectional instability procedures exhibited the least pronounced gender differences. Future modeling from 2018-2030 projected continued steady rise in arthroscopic Bankart (40,000-49,000 case/yr), rapid growth in Latarjet (1370-4300 cases/yr), and continued decline in open Bankart (1000-250 cases/yr) procedures.

CONCLUSIONS

Arthroscopic Bankart continues to be the most common glenohumeral instability procedure in the U.S. From 2009 to 2018, incidence of open Bankart procedures declined while Latarjet procedures markedly increased. Future projections to 2030 mirrored these findings. These data may provide an enhanced understanding of the evolution of surgical treatment of glenohumeral instability within the U.S. laying the foundation for continued prospective studies into the appropriate indications and advancements in surgical techniques.

Anteromedialization Tibial Tubercle Osteotomy Improves Patellar Contact Forces: A Cadaveric Model of Patellofemoral Dysplasia

BACKGROUND

Patellofemoral (PF) dysplasia is common in patients with recurrent patellar instability. Tibial tubercle osteotomy (TTO) is performed with goals of correcting patellar maltracking and redistributing contact forces across the PF joint. The biomechanical effects of TTO in the setting of PF dysplasia have not been quantified.

PURPOSE/HYPOTHESIS

To quantify patellar contact mechanics and kinematics after TTO in the setting of PF dysplasia. We hypothesized that a simulated anteromedialization (AMZ) TTO would improve PF contact mechanics as compared with a pure medialization TTO.

STUDY DESIGN

Controlled laboratory study.

METHODS

PF dysplasia with Dejour type D classification was simulated in 7 cadaveric knees by replacing the native patellar and trochlear surfaces with synthetic polymeric patellar and trochlear implants. On each specimen, a flat TTO was fixed in 3 distinct positions simulating a pathologic lateralized tubercle (pathologic condition), a medialized tubercle (Elmslie Trillat), and an AMZ tubercle. The sum of forces acting on the medial and lateral patellar facet and patellar kinematics was computed for each knee for each condition from 0° to 70° of flexion at 10° increments.

RESULTS

Relative to the pathologic condition, AMZ TTO decreased contact forces across the lateral facet (20°-50° and 70° of flexion). Relative to the pathologic condition, Elmslie Trillat TTO had no effect on contact forces on either compartment. Relative to the Elmslie Trillat TTO, the AMZ TTO had significantly decreased contact forces across the medial facet (at 40°, 60°, and 70° of flexion). No significant differences in joint kinematics occurred across any groups.

CONCLUSION

Of all groups studied, AMZ TTO resulted in significantly decreased patellar contact forces in simulated dysplastic PF joints. AMZ may be considered in certain patients with PF dysplasia to avoid medial compartment PF chondral overload.

CLINICAL RELEVANCE

PF dysplasia is common in patients with recurrent patellar instability who warrant surgical intervention to prevent subsequent recurrence. Numerous interventions to treat this condition, including various TTOs, have been proposed without a clear consensus. This cadaveric biomechanical study demonstrates that AMZ TTO resulted in more favorable PF contact mechanics than Elmslie Trillat TTO in a model representing PF dysplasia. AMZ TTO may be considered for patients in the setting of recurrent instability with PF dysplasia to avoid cartilage overload on the medial compartment of the PF joint.

A Landmark-Based Technique for Determining an Isometric Femoral Attachment Site for Lateral Extraarticular Tenodesis is Inaccurate

Purpose

To evaluate the reliability and accuracy of a method of placing the femoral fixation location for lateral extra-articular tenodesis (LET) within a safe isometric area using anatomic landmarks.

Methods

Using a pilot cadaveric specimen, the center of the radiographic safe isometric area for femoral fixation of LET, defined as a 1 cm (proximal-distal) area located proximal to the metaphyseal flare and posterior to the posterior cortical extension line (PCEL), was located using fluoroscopy and found to be 20 mm directly proximal to the center of the fibular collateral ligament (FCL) origin. Using 10 additional specimens, the center of the FCL origin and a location 20 mm directly proximal was identified. K-wires were placed at each location. A lateral radiograph was obtained, and distances of the proximal K-wire relative to the PCEL and metaphyseal flare were measured. The location of the proximal K-wire relative to the radiographic safe isometric area was assessed by 2 independent observers. Intrarater and inter-rater reliability was calculated for all measurements using intraclass coefficients (ICCs).

Results

There was excellent intrarater and inter-rater reliability for all radiographic measurements (.908 to .975 and .968 to .988, respectively). In 5/10 specimens, the proximal K-wire was outside of the radiographic safe isometric area, with 4/5 anterior to the PCEL. Overall, the mean distance from the PCEL was 1 mm ± 4 mm (anterior), and the mean distance from the metaphyseal flare was 7.4 mm ± 2.9 mm (proximal).

Conclusion

A landmark-based technique referencing the FCL origin was inaccurate in the placement of femoral fixation within a radiographic safe isometric area for LET. Therefore intraoperative imaging should be considered to ensure accurate placement.

Clinical Relevance

These findings may help to decrease the likelihood of misplacement of femoral fixation during LET by showing that landmark-based methods without intraoperative image guidance may be unreliable.

Three Medial All Suture Anchors Improves Contact Force Compared to Two Hard Body Anchors in a Biomechanical Two-Tendon Rotator Cuff Tear Model

Purpose

To biomechanically compare a knotless double-row construct with 3 medial all-suture (3AS) anchors with a standard 2 medial hard body (2HB) anchor construct.

Methods

Twelve matched cadaveric shoulder specimens with a mean age of 57 years (range: 54-61 years) were randomized to receive a knotless double-row repair with either a 3AS or 2HB construct. In the 3AS construct, three 2.6-mm all-suture anchors were placed adjacent to the articular margin and secured laterally with two 4.75-mm knotless hard body anchors. In the 2HB construct, two 4.75-mm medial hard body anchors were placed medially, lateral fixation was identical to the 3AS construct. Creep, displacement, stiffness, and ultimate load were recorded for each sample. In addition, a SynDaver model was used to compare contact pressure between the 2 repair constructs.

Results

There were no differences in cyclic displacement at 1, 30, and 100 cycles (P = .616, .497, .190, respectively), cyclic stiffness (.928), ultimate load (.445), or load to failure (P = .445) between the 2 constructs. The 3AS repair construct had improved contact pressure between tendon and bone when compared with the 2HB construct at loads of 20 N, 30 N, and 40 N (P = .01, .02, and .04, respectively).

Conclusions

Displacement and load to failure properties are similar between knotless constructs using either 2HB or 3AS for the medial row. However, contact force may improve with the use of 3 medial all-suture anchors.

Clinical Relevance

As all-suture anchors are smaller in size when compared with hard body anchors. For this reason, there is potential to place an additional all-suture medial anchor to improve contact force and potentially improve rotator cuff healing when compared with the use of hard body anchors.

Liposomal Bupivacaine and Ropivacaine Adductor Canal Blocks for Anterior Cruciate Ligament Reconstruction Provide Similar Postoperative Analgesia

The purpose of this study was to compare postoperative pain following anterior cruciate ligament (ACL) reconstruction (ACLR) in patients receiving an adductor canal block (ACB) with ropivacaine (R-ACB) or liposomal bupivacaine (LB-ACB). The secondary purpose was to compare opioid consumption. A prospective cohort study of patients undergoing ACLR at an academic medical center was conducted from November 1, 2018 to November 21, 2019. The first cohort received R-ACB and 30 tablets of 5/325 mg oxycodone/acetaminophen. After June 13, 2019, the second cohort received LB-ACB and 20 tablets of 5/325 mg oxycodone/acetaminophen with the reduction in opioids prescribed resulting from a hospital quality improvement initiative to decrease narcotic consumption. From postoperative days 0 through 6, pain was assessed thrice daily using a numeric rating scale. Total postoperative opioid consumption was reported via tablet count and converted to oral morphine equivalents (OMEs). During this period, 165 subjects underwent ACLR, and 126 met the eligibility criteria (44.4% female, 55.6% male; mean ± standard deviation: 28.7 ± 13.7 years). Sixty-six (52.4%) received LB-ACB, and 60 (47.6%) received R-ACB (p = 0.53). The most common graft utilized was quadriceps autograft (63.6% LB-ACB; 58.3% R-ACB, p = 0.76). Mean postoperative pain scores were similar between groups during the entire postoperative period (p ≥ 0.08 for POD 0-6). While postoperative opioid consumption was lower among patients receiving LB-ACB (median OME [interquartile range]: 28.6 [7.5-63.8] vs. 45.0 [15.0-75.0], p = 0.023), this only amounted to an average of 2.2 tablets. Patients receiving LB-ACB in the setting of ACLR reported similar postoperative pain compared with those receiving R-ACB. Despite the second aim of our study, we cannot make conclusions about the effect of each block on opioid consumption given that each cohort received different numbers of opioid tablets due to institutional pressure to reduce opioid prescribing. As few patients completed their opioid prescriptions or requested refills, further reduction in prescription size is warranted. Future studies are necessary to further elucidate the effect of LB-ACB versus R-ACB on postoperative pain and opioid consumption after ACLR.

Radiographic and Clinical Evidence for Osteoarthritis at Medium-Term Follow-up after Arthroscopic Partial Medial Meniscectomy

OBJECTIVE

The purpose of this study is to assess if incident radiographic osteoarthritis (OA) is associated with clinical OA symptoms at midterm follow-up after arthroscopic partial medial meniscectomy (APMM).

DESIGN

A total of 44 patients (43% females, mean age 50.1 ± 2.8 years, minimum 5.6-year follow-up) with isolated medial meniscal tears and no-to-mild preoperative radiographic OA underwent APMM. Incident radiographic OA was assessed using the modified Kellgren-Lawrence (K-L) classification. Patients completed the Knee Injury and Osteoarthritis Outcomes Score (KOOS), and subscale thresholds for assessment of a symptomatic knee (KOOS OA criteria) and for Patient non-Acceptable Symptom State (PASS-N) following anterior cruciate ligament reconstruction (ACL-R) were calculated.

RESULTS

Incident medial compartment OA occurred in 50% of patients. Morbidly obese patients (body mass index ≥35 kg/m²) were more likely to demonstrate incident radiographic OA (100% vs. 41%, P = 0.002). Forty-three percent of patients met KOOS OA criteria, while 77% were PASS-N. Females were more likely to meet KOOS OA criteria (73% vs. 21%, P = 0.009). Patients with incident radiographic OA in any compartment were more likely than those without radiographic OA to meet KOOS OA criteria (71% vs. 17%, P = 0.008). Patients with preoperative K-L grade 2 changes in any compartment were more likely to meet KOOS OA criteria than those without K-L grade 2 changes in any compartment (83% vs. 35%, P = 0.037).

CONCLUSIONS

Roughly half of APMM patients will have incident radiographic OA within 6 years of APMM, and this risk increases with obesity. Females and patients with incident radiographic OA are more likely to meet clinical thresholds for OA.

Evaluation of the Effectiveness of Newer Helmet Designs with Emergent Shell and Padding Technologies Versus Older Helmet Models for Preserving White Matter Following a Season of High School Football

We aimed to objectively compare the effects of wearing newer, higher-ranked football helmets (HRank) vs. wearing older, lower-ranked helmets (LRank) on pre- to post-season alterations to neuroimaging-derived metrics of athletes' white matter. Fifty-four high-school athletes wore an HRank helmet, and 62 athletes wore an LRank helmet during their competitive football season and completed pre- and post-season diffusion tensor imaging (DTI). Longitudinal within- and between-group DTI metrics [fractional anisotropy (FA) and mean/axial/radial diffusivity (MD, AD, RD)] were analyzed using tract-based spatial statistics. The LRank helmet group exhibited significant pre- to post-season reductions in MD, AD, and RD, the HRank helmet group displayed significant pre- to post-season increases in FA, and both groups showed significant pre- to post-season increases in AD (p's < .05 [corrected]). Between-group analyses revealed the pre- to post-season increase in AD was significantly less for athletes wearing HRank compared to LRank (p < .05 [corrected]). These data provide in vivo evidence that wearing an HRank helmet may be efficacious for preserving white matter from head impact exposure during high school football. Future prospective longitudinal investigations with complimentary imaging and behavioral outcomes are warranted to corroborate these initial in vivo findings.

Utility of the Merchant View Radiograph for Assessment of Tibial Tubercle-Trochlear Groove Distance: A Comparison to MRI in Pediatric and Adolescent Patients

BACKGROUND

Plain radiographic evaluation remains the standard initial assessment of patellar instability, while 3-dimensional imaging is obtained in some patients. Merchant radiographs can demonstrate the tibial tubercle relative to the trochlear groove (TT-TG), but the determination of the TT-TG from these radiographs has been abandoned since its original description. The purpose of this study is to evaluate the utility of the TT-TG measured on Merchant radiographs for the assessment of patellar instability.

METHODS

A prospective cohort study was performed of pediatric and adolescent patients aged 10 to 18 who underwent standardized Merchant radiographs, including a total of 98 knees (in 57 patients). Merchant TT-TG was measured as the distance between the center of the trochlear groove and the tibial tubercle, with both lines perpendicular to the anterior femoral condylar axis. In Part 1, the Merchant TT-TG measured by the tibial tubercle radiographic appearance was compared with the measurement utilizing a radiographic marker. In Part 2, the Merchant TT-TG was compared with the magnetic resonance imaging (MRI) TT-TG distance using bivariate linear regression analysis. TT-TG measurements were compared in patients with and without patellar instability with receiver operating characteristic curve analysis.

RESULTS

The tibial tubercle was identified on Merchant radiograph in 81.7% (67/82) of knees, and there was an excellent correlation (Pearson correlation coefficient=0.85) between the Merchant TT-TG and the measurement based on marker placement. Merchant TT-TG was on average 4.5 mm less than MRI TT-TG (12.8±4.4 vs. 8.4±7.7 mm, P<0.001) and was moderately correlated (Pearson correlation coefficient=0.58, P<0.01). TT-TG distance was increased in patients with patellar instability compared with those without patellar instability on the Merchant view (10.5±6.9 vs. 2.0±5.5 mm, P<0.001) and MRI (13.9±4.4 vs. 10.5±2.9 mm, P=0.012). Merchant TT-TG also demonstrated a higher area under the curve than MRI TT-TG (0.872 vs. 0.775) in differentiating patients with and without patellar instability.

CONCLUSIONS

Standardized Merchant radiographs allow for reliable assessment of the Merchant TT-TG distance when the tibial tubercle is visualized and moderately correlate with MRI TT-TG (with Merchant TT-TG on average 4.5 mm less than MRI).

LEVEL OF EVIDENCE

Level III.

Postoperative Disposal of Unused Opioids: A Systematic Review

Introduction: Opioid misuse and overprescription have contributed to a national public health crisis in the United States. Postoperatively, patients are often left with unused opioids, which pose a risk for diversion if not appropriately disposed of. Patients are infrequently provided instructions on safe disposal methods of surplus opioids. Purpose: We sought to determine the current rates of disposal of unused opioids and the reported disposal mechanisms for unused opioids that were prescribed for acute postoperative pain control. Methods: A systematic review was performed of the PubMed, Cochrane, and Embase databases for relevant articles from their earliest entries through October 2, 2019. We used the search terms "opioid" or "narcotic" and "disposal" and "surgery." Studies were considered for inclusion if they reported the rate of disposal of unused opioids following surgery. A screening strategy was used to identify relevant articles using Covidence. For studies meeting inclusion criteria, relevant information was extracted. Results: Sixteen studies met inclusion criteria. We found that surplus opioid disposal rates varied widely, from 4.9% to 87.0%. Among studies with no intervention (opioid disposal education or drug disposal kit/bag), rates of opioid disposal ranged from 4.9% to 46.5%. While 7 studies used opioid disposal education as an intervention, only 3 showed a significant increase in surplus opioid disposal compared with standard care. All 3 studies that used an opioid disposal kit or bag as an intervention demonstrated significant increases in opioid disposal. Conclusions: Baseline rates of surplus opioid disposal are relatively low in the postoperative setting. Our findings suggest that opioid disposal kits significantly increase rates of surplus opioid disposal postoperatively. Further research, including a large-scale cost-benefit analysis, will be necessary prior to recommending widespread implementation of drug disposal kits or bags.

Current Orthopaedic Health Economic Literature: Quality Is High but Ethical and Societal Perspectives Are Lacking

PURPOSE

To evaluate the quality of orthopaedic cost-effectiveness analyses (CEAs) in accordance with the 2016 recommendations by the Second Panel on Cost-Effectiveness in Health and Medicine.

METHODS

A systematic review of all CEAs from September 2017 to September 2019 in the 10 highest impact orthopaedic surgery journals was performed. Quality scoring used the Quality of Health Economic Studies (QHES) instrument and the Second Panel checklist. QHES scores ≥80 were considered high quality and <50 poor quality. Mann-Whitney U and independent samples Kruskal-Wallis tests compared individual and multiple groups, respectively. Linear regression analysis was performed to correlate QHES score, checklist item fulfillment, and impact factor.

RESULTS

The 10 highest impact orthopaedic journals published 6,323 articles with 35 (0.55%) meeting inclusion criteria. Total joint arthroplasty (TJA) and sports medicine articles comprised 65.7% of included studies. Overall mean QHES score was 89.0 ± 7.6, with 82.8% considered high quality. Mean proportion of Second Panel checklist items fulfilled was 82.1% ± 13.3%, but no studies performed an impact inventory accounting for consequences within and outside the health care sector or discussed ethical implications. Mean QHES score and satisfied checklist items were significantly different by journal (P = .025 and P = .01, respectively). In addition, there was a moderate positive correlation between QHES score and impact factor (r = 0.446, P = .007). TJA CEAs satisfied a higher number of checklist items compared with spine surgery CEAs.

CONCLUSIONS

Recent orthopaedic CEAs have generally been high quality according to updated Second Panel guidelines but consistently miss checklist items relating to societal impact and ethics. TJA and sports medicine continue to be the most frequently studied orthopaedic subspecialties in health economics, and the breadth of orthopaedic procedures analyzed by CEAs has improved.

STUDY DESIGN

Level IV, systematic review.

Computed Tomography-Based Preoperative Planning Provides a Pathology and Morphology-Specific Approach to Glenohumeral Instability With Bone Loss

PURPOSE

To use computed tomography (CT) to determine a reproducible method of coracoid measurement to compare the ability of the classic Latarjet technique and the congruent arc modification (CAM) to restore native glenoid diameter and to develop a preoperative planning algorithm for glenoid restoration with a goal of achieving an on-track shoulder.

METHODS

Coracoid dimensions were measured on multiplanar reconstructed shoulder CT scans of patients aged 18 to 45 years obtained between December 1, 2019, and March 13, 2020. Patients were excluded if CT demonstrated osteophyte formation, glenoid dysplasia, coracoid fracture, or tumor. The proportion of glenoid diameter able to be restored using classic Latarjet technique and CAM were calculated. A treatment algorithm was proposed considering the amount of bone loss present and coracoid dimensions.

RESULTS

Coracoid dimensions of 117 consecutive patients were measured and varied considerably (length: 17.5-31.8 mm, width: 9.1-20.5 mm, thickness: 6.1-15.7 mm). While most patients had harvestable coracoid length ≥20 mm (male: 96.3% vs female: 94.4%, P = .65), only 27.8% of female patients had coracoid thickness ≥10 mm. When comparing Latarjet techniques, there was no difference in the proportion of patients in whom 30% glenoid diameter could be fully restored, but CAM was able to restore at least 35% in more male and female patients (98.8% vs 79.0% and 100% vs 61.1%, respectively, P = .00001). Intra- and inter-rater reliability was excellent ( intraclass correlation coefficient ≥0.950 for all dimensions).

CONCLUSIONS

We describe a reliable method of measuring coracoid dimensions for preoperative planning of glenoid restoration. The classic Latarjet technique reliably restores the glenoid anteroposterior diameter with bone loss of up to 30%. The majority of female patients have coracoid thickness <10 mm, which may increase the risk of graft fracture when using CAM. The decision to use the classic Latarjet technique or CAM considers each individual's glenoid and coracoid dimensions with a goal of achieving an on-track shoulder.

CLINICAL RELEVANCE

Our reliable method of coracoid measurement demonstrated the differing abilities of the classic Latarjet and CAM to restore the native glenoid diameter. An evidence-based algorithm using these measurements was developed to assist in preoperative planning for glenohumeral instability in the setting of bone loss, with a goal of achieving an on-track shoulder. Alternative techniques may be considered if an on-track shoulder cannot be achieved with Latarjet.

Arthroscopic-Assisted Coracoclavicular Ligament Reconstruction: Clinical Outcomes and Return to Activity at Mean 6-Year Follow-Up

PURPOSE

To report clinical and functional outcomes including return to preinjury activity level following arthroscopic-assisted coracoclavicular (CC) ligament reconstruction (AA-CCR) and to determine associations between return to preinjury activity level, radiographic outcomes, and patient-reported outcomes following AA-CCR.

METHODS

A institutional registry review of all AA-CCR using free tendon grafts from 2007 to 2016 was performed. Clinical assessment included Single Assessment Numeric Evaluation (SANE) score and return to preinjury activity level at final follow-up. Treatment failure was defined as (1) revision acromioclavicular stabilization surgery, (2) unable to return to preinjury activity level, or (3) radiographic loss of reduction (RLOR, >25% CC distance compared with contralateral side). SANE scores, return to activity, and RLOR were compared between patients within each category of treatment failure, by grade of injury, and whether concomitant pathology was treated.

RESULTS

There were 88 patients (89.8% male) with mean age of 39.6 years and minimum 2-year clinical follow-up (mean 6.1 years). Most injuries were Rockwood grade V (63.6%). Mean postoperative SANE score was 86.3 ± 17.5. Treatment failure occurred in 17.1%: 8.0% were unable to return to activity, 5.7% had RLOR, and 3.4% underwent revision surgery due to traumatic reinjury. SANE score was lower among patients who were unable to return to activity compared with those with RLOR and compared with nonfailures (P = .0002). There were no differences in revision surgery rates, return to activity, or SANE scores according to Rockwood grade or if concomitant pathology was treated.

CONCLUSIONS

AA-CCR with free tendon grafts resulted in good clinical outcomes and a high rate of return to preinjury activity level. RLOR did not correlate with return to preinjury activity level. Concomitant pathology that required treatment did not adversely affect outcomes. Return to preinjury activity level may be a more clinically relevant outcome measure than radiographic maintenance of acromioclavicular joint reduction.

LEVEL OF EVIDENCE

IV (Case Series).

Lower Extremity Compartment Syndrome in National Football League Athletes

BACKGROUND

The purpose of this study was to evaluate the incidence of lower extremity compartment syndrome in National Football League (NFL) athletes and report the mechanisms of injury, methods of treatment, and subsequent days missed. We review the existing literature on lower extremity compartment syndrome in athletic populations.

HYPOTHESIS

Lower extremity compartment syndrome occurs with a low incidence in NFL athletes, and there is a high return-to-play rate after surgical management of acute compartment syndrome.

STUDY DESIGN

Case series.

LEVEL OF EVIDENCE

Level 4.

METHODS

A retrospective review of recorded cases of lower extremity compartment syndrome from 2000 to 2017 was performed using the NFL Injury Surveillance System and electronic medical record system. Epidemiological data, injury mechanism, rates of surgery, and days missed due to injury were recorded.

RESULTS

During the study period, 22 cases of leg compartment syndrome in 21 athletes were recorded. Of these injuries, 50% occurred in games and 73% were the result of a direct impact to the leg. Concomitant tibial fracture was noted in only 2 cases (9.1%) and there was only 1 reported case of chronic exertional compartment syndrome. Surgery was documented in 15 of 22 cases (68.2%). For acute nonfracture cases, the average time missed due to injury was 24.2 days (range, 5-54 days), and all were able to return to full participation within the same season.

CONCLUSION

NFL athletes with acute leg compartment syndrome treated with surgery exhibited a high rate of return to play within the same season.

CLINICAL RELEVANCE

Although compartment syndrome is a relatively rare diagnosis among NFL players, team physicians and athletic trainers must maintain a high index of suspicion to expediently diagnose and treat this potentially limb-threatening condition.

The Virtual Shoulder and Knee Physical Examination

The COVID-19 crisis has forced a sudden and dramatic shift in the way that clinicians interact with their patients, from outpatient encounters to telehealth visits utilizing a variety of internet-based videoconferencing applications. Although many aspects of pre–COVID-19 outpatient sports medicine care will ultimately resume, it is likely that telehealth will persist because of its practicality and because of patient demand for access to efficient and convenient health care. Physical examination is widely considered a critical obstacle to a thorough evaluation of sports medicine patients during telehealth visits. However, a closer reflection suggests that a majority of the examination maneuvers are possible virtually with limited, if any, modifications. Thus, we provide a comprehensive shoulder and knee physical examination for sports medicine telehealth visits, including (1) verbal instructions in layman’s terms that can be provided to the patient before or read verbatim during the visit, (2) multimedia options (narrated videos and annotated presentations) of the shoulder and knee examination that can be provided to patients via screen-share options, and (3) a corresponding checklist to aid in documentation.

Physiologic Long Head Biceps Tendon Excursion Throughout Shoulder Range of Motion: A Cadaveric Study

Background:

Restoration of the long head of the biceps tendon (LHBT) length-tension relationship is critical in preserving muscle strength and efficiency when performing biceps tenodesis. While static anatomic landmarks such as the inferior border of the pectoralis major may be used intraoperatively to achieve this, shoulder position may affect the excursion of the biceps tendon and represents another variable to consider.

Purpose/Hypothesis:

The purpose of this study was to quantitatively evaluate the normal excursion of LHBT that occurs through a glenohumeral range of motion. We also sought to determine whether elbow position affects LHBT excursion. We hypothesized that LHBT excursion will be affected by glenohumeral flexion and extension, and elbow extension will result in increased excursion at each glenohumeral position compared with a neutral position.

Study Design:

Controlled laboratory study.

Methods:

A total of 10 fresh-frozen specimens underwent a standard approach for subpectoral biceps tenodesis. The LHBT was identified and tagged with a radiopaque marker within zone 3 of the bicipital tunnel. A total of 3 K-wires were then drilled into the osseous floor: one at the level of the marker in the LHBT, one at 1 cm proximal, and a third 1 cm distal. All 3 K-wires were then cut flush with the anterior humeral cortex. The specimens were next placed into 8 different positions, and the excursion of the LHBT was measured by referencing the K-wires using static fluoroscopic imaging. The results were analyzed using 1-way analysis of variance testing followed by Tukey honestly significant difference testing for pairwise comparison between each individual position and the reference position.

Results:

The average total LHBT excursion was 24.4 ± 5.2 mm between the neutral shoulder position and the other shoulder positions tested. The position of the LHBT was significantly different in the reference position compared with each of the other 7 shoulder positions (P < .001). Additionally, the 2 positions of shoulder extension had different LHBT excursions when compared with each position of shoulder flexion (P < .0001). For each shoulder position tested, the position of the LHBT was not significantly different in elbow flexion compared with extension.

Conclusion:

There is approximately 24 mm of LHBT excursion throughout the glenohumeral range of motion, with significantly different amounts of excursion in glenohumeral flexion and extension. Elbow position does not significantly affect LHBT excursion. Positioning the shoulder in extension during biceps tenodesis may overtension the biceps, while positioning the shoulder in flexion may undertension the biceps relative to the neutral position. Further research is needed to identify the optimal shoulder position for biceps tenodesis.

Clinical Relevance:

Shoulder positioning is an important consideration in establishing a normal length-tension relationship during biceps tenodesis. When compared with flexed shoulder positions, LHBT excursion significantly differs in positions of extension and in a neutral position.

Gene Expression in Meniscal Tears at the Time of Arthroscopic Partial Meniscectomy Predicts the Progression of Osteoarthritis Within 6 Years of Surgery

Background:

While knees with meniscal tears are associated with a heightened risk of developing osteoarthritis (OA), it is difficult to predict which patients are at the greatest risk for OA. Gene signatures in menisci that are resected during arthroscopic partial meniscectomy (APM) may provide insight into the risk of OA progression.

Hypothesis:

Meniscal gene signatures at the time of APM will predict radiographic OA progression.

Study Design:

Case series; Level of evidence, 4.

Methods:

Meniscal fragments were collected from 38 patients without OA during clinically indicated APM of the medial meniscus. The expression of 28 candidate genes with known roles in cartilage homeostasis, OA, extracellular matrix degradation, and obesity was assessed by quantitative real-time polymerase chain reaction. Weightbearing radiographs obtained before surgery and at final follow-up were graded by a musculoskeletal radiologist using the Kellgren-Lawrence classification of OA. The association of meniscal gene expression at baseline with the progression of radiographic OA was determined.

Results:

Gene expression and baseline and follow-up radiographic data were available from 31 patients (81.6%) at a mean follow-up of 6.2 ± 1.3 years. Patients without OA progression had significantly higher expression of 7 genes: MMP9 (5.1-fold; P = .002), IL8 (2.9-fold; P = .016), CCL3 (3.7-fold; P = .032), CCL3L1 (4.5-fold; P = .008), CXCL6 (6.2-fold; P = .010), LEP (5.2-fold; P = .004), and RETN (46-fold; P = .008).

Conclusion:

Gene expression in the meniscus at the time of APM may be associated with the risk for progression of OA after surgery. Elevated expression of the aforementioned genes may reflect a chondroprotective response. Stratifying the risk for OA progression after APM could facilitate targeted interventions to delay or prevent the development of OA. Further studies in a larger cohort with an extended follow-up, and inclusion of additional genes, are warranted to better characterize this association.

State of the Union on Ulnar Collateral Ligament Reconstruction in 2020: Indications, Techniques, and Outcomes

PURPOSE OF REVIEW

There has been a marked increase in the number of ulnar collateral ligament reconstructions performed annually and an associated increase in the amount of recent literature published. It is paramount that surgeons remain up to date on the current literature, as modern indications and surgical techniques continue to improve clinical outcomes.

RECENT FINDINGS

Our understanding of ulnar collateral ligament (UCL) injuries, treatment indications, and surgical techniques for UCL reconstruction continues to evolve. Despite the rapidly increasing amount of published literature on the topic, a clear and concise surgical algorithm is lacking. Studies have suggested a trend towards improved clinical outcomes and decreased complications with various modifications in UCL reconstruction techniques. Current sport-specific outcome studies have reported conflicting results regarding the effect of UCL reconstruction on an athlete's performance upon returning to sport. With the rising incidence of UCL reconstruction and growing media attention, UCL injuries, reconstruction techniques, and return to sport following UCL surgery are timely topics of interest to clinicians and overhead throwing athletes. Several technique modifications have been reported, and these modifications may lead to improved outcomes and lower complication rates. Studies assessing sport-specific outcome measures will be necessary to provide a more critical and informative analysis of outcomes following UCL reconstruction.

A Practical Guide for the Current Use of Biologic Therapies in Sports Medicine

Over the past decade, there has been an increased interest in the use of biologic therapies in sports medicine. Although these technologies are in relatively early stages of development, there have been substantial increases in marketing, patient demand, and clinical utilization of biologics, including platelet-rich plasma, bone marrow aspirate concentrate, and other cell-derived therapies. Direct-to-consumer marketing of biologics has also proliferated but is largely unregulated, and clinicians must accurately convey the safety and efficacy profiles of these therapies to patients. Because most insurance companies consider biologic treatments to be experimental or investigational for orthopaedic applications given the lack of high-quality evidence to support their efficacy, patients receiving these treatments often make substantial out-of-pocket payments. With a range of treatment costs among centers offering biologics, there is a need for appropriate and sustainable pricing and reimbursement models. Clinicians utilizing biologics must also have a thorough understanding of the recently clarified Food and Drug Administration guidelines that regulate the clinical use of cell and tissue products. There is a lack of consensus on the optimal preparation, source, delivery method, and dosing of biologic therapies, which has been exacerbated by a lack of sufficient experimental detail in most published studies. Future research must better identify the biologic target of treatment, adhere to better standards of reporting, and better integrate researchers, industry, and regulatory bodies to optimize applications.

Severity of Glenohumeral Osteoarthritis Does Not Correlate With Patient-Reported Outcomes

Background

Patient pain and clinical function are important factors in decision-making for patients with glenohumeral osteoarthritis (GHOA). The correlation between radiographic severity of arthritis and demographic factors with modern patient-reported outcome measures has not yet been well defined.

Methods

This cross-sectional study included 256 shoulders in 246 patients presenting with isolated GHOA. All patients obtained standard radiographs and completed the American Shoulder and Elbow Surgeons score, Simple Shoulder Test (SST), Shoulder Activity Scale, Visual Analog Scale, and Patient-Reported Outcome Measurement Information System (PROMIS) computer adaptive tests at the time of presentation. Radiographs were graded according to the Samilson–Prieto classification. Mean pain and functional scores were compared between the radiographic grades of osteoarthritis (OA) and demographic factors.

Results

There were 6 shoulders rated as grade 1 OA, 41 shoulders as grade 2, 149 shoulders as grade 3a, and 65 shoulders as grade 3b. There was excellent interobserver reliability in grade of OA (κ = 0.77). There were no significant differences in patient-reported pain or any validated measure of clinical function between radiographic grades of OA (P > .05). Males reported higher function and lower pain scores than females (P = .001–.066), although only the values for the SST and PROMIS physical function test were clinically relevant.

Discussion

While gender correlated with pain and function, the clinical relevance is limited. Radiographic severity of GHOA does not correlate with patient-reported pain and function, and symptoms should remain the primary determinants of surgical decision-making. Further investigation is necessary to examine whether radiographic severity of OA influences improvement following operative intervention in this population.

Risk of Subsequent Joint Arthroplasty in Contralateral or Different Joint After Index Shoulder, Hip, or Knee Arthroplasty: Association with Index Joint, Demographics, and Patient-Specific Factors

BACKGROUND

The risk of subsequent joint replacement following an index joint replacement for osteoarthritis and the association of this risk with demographic and patient-specific factors are not well understood. The purpose of this study was to determine how demographic and other patient-specific factors are associated with the risk of subsequent joint replacement in the contralateral or a different joint following an index joint replacement for osteoarthritis.

METHODS

The Healthcare Cost and Utilization Project (HCUP) State Inpatient Database (SID) of New York was used to identify the first (primary) total hip arthroplasty (THA), total knee arthroplasty (TKA), or total shoulder arthroplasty (TSA) and the risk of subsequent joint replacement in the contralateral or a different joint over 5 to 8 years. The association of demographic and other patient-specific factors with subsequent joint replacement was assessed via multivariable Cox proportional hazards modeling. We also investigated the time between the index and subsequent joint replacement.

RESULTS

Of 85,616 patients, 20,223 (23.6%) underwent a subsequent replacement of the contralateral joint within 5 to 8 years (median, 343 days) after the index joint replacement. The strongest predictors were obesity (adjusted hazard ratio [HR] = 1.28; p < 0.001) and index TKA compared with THA (1.72; p < 0.001). A total of 3,197 patients (3.7%) underwent a subsequent replacement of a different joint within 5 to 8 years (median, 876 days) after the index joint replacement. The strongest predictors were obesity (adjusted HR = 1.41; p < 0.001) and index TSA compared with THA (adjusted HR = 2.52; p < 0.001).

CONCLUSIONS

There is a relatively high risk of subsequent replacement of the contralateral joint and a relatively low risk of subsequent replacement of a different joint within 5 to 8 years after an index THA, TKA, or TSA. Obesity was associated with a higher risk of subsequent replacement of the contralateral joint or a different joint.

LEVEL OF EVIDENCE

Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Outcomes From Conservative Treatment of Shoulder Idiopathic Adhesive Capsulitis and Factors Associated With Developing Contralateral Disease

Background:

Idiopathic adhesive capsulitis is a common condition resulting in painful multidirectional restriction of motion without other identifiable shoulder abnormality. First-line therapies for this condition are nonoperative, but limited data are available regarding which treatments are most effective. Factors associated with contralateral disease are not well established.

Hypothesis:

Younger patients will have a better response to treatments, and older patients and patients with diabetes will be more likely to develop contralateral disease.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

Patients diagnosed with idiopathic adhesive capsulitis were treated with a single intra-articular glenohumeral injection of local anesthetic and corticosteroid as well as 4 weeks of supervised physical therapy (PT). Patients were re-evaluated monthly and received additional conservative treatment based on failure to restore normal motion. Patient-reported outcome scores and range of motion were used to assess treatment efficacy.

Results:

Minimum 2-year follow-up data (mean, 3.4 years) were available for 60 of 75 eligible patients (80%). Patients who did not attend supervised PT as prescribed were more likely to undergo repeat injection due to a lack of adequate range of motion at follow-up (P = .003). Conservative therapy failed in 2 patients (3.3%), and they underwent arthroscopic release and manipulation under anesthesia. Twenty-two patients (36.7%) were subsequently diagnosed with contralateral idiopathic adhesive capsulitis, with a higher incidence in patients with diabetes (P = .009) and patients younger than 50 years (P = .005). American Shoulder and Elbow Surgeons score improved from 41.2 (95% CI, 33.0-49.4) at baseline to 92.0 (95% CI, 88.4-95.6) at final follow-up (P < .0001). Patients with diabetes had a decrease in Shoulder Activity Scale score at final follow-up (P = .049).

Conclusion:

Conservative treatment for idiopathic adhesive capsulitis resulted in good clinical outcomes with a low incidence of surgical intervention. Physical therapy reduced the use of a second injection as part of treatment in this treatment algorithm. Young patients and patients with diabetes may be more likely to develop contralateral disease.

Meta-analysis of the Risk of Infections After Anterior Cruciate Ligament Reconstruction by Graft Type

BACKGROUND

An infection after anterior cruciate ligament (ACL) reconstruction is a relatively rare but challenging complication. There are no meta-analyses comparing the incidence of infections after ACL reconstruction with the various available graft choices.

PURPOSE

To compare the incidence of infections after ACL reconstruction with bone-patellar tendon-bone (BPTB) autografts compared with hamstring autografts, with a secondary aim of comparing the incidence of infections after reconstruction with autografts compared with allografts.

STUDY DESIGN

Meta-analysis.

METHODS

A systematic review was performed to identify level 1 and 2 studies that reported the incidence of infections by graft type after ACL reconstruction. Studies that evaluated patients undergoing primary ACL reconstruction with an autograft, allograft, or combination of autograft and allograft and reported the number of postoperative infections by graft type utilized were considered for inclusion. Studies were excluded if they included revision ACL reconstruction or did not specify the number of infections by graft type. Study findings were reviewed, and meta-analysis was performed when data were sufficiently homogeneous.

RESULTS

Twenty-one studies meeting criteria were identified from the literature review. Meta-analysis revealed a significant difference in the incidence of deep infections between BPTB autografts and hamstring autografts, with the BPTB group displaying a 77% lower incidence of infections compared with the hamstring group (relative risk [RR], 0.23; 95% CI, 0.097-0.54). The incidence of infections was 66% lower with BPTB autografts compared with all other graft types, with a pooled RR of 0.33 (95% CI, 0.15-0.71). There was no significant difference in the incidence of infections after ACL reconstruction with autografts compared with allografts (RR, 1.035; 95% CI, 0.589-1.819).

CONCLUSION

The findings of this meta-analysis demonstrate a significantly lower incidence of deep infections after ACL reconstruction with BPTB autografts compared with hamstring autografts but not compared with allografts.

CLINICAL RELEVANCE

Although the overall infection rate after ACL reconstruction is relatively low, the significantly higher rate of infections with hamstring autografts compared with BPTB autografts should be a consideration when discussing graft choices for ACL reconstruction.

Treatment of Failed Articular Cartilage Reconstructive Procedures of the Knee: A Systematic Review

Background

Symptomatic articular cartilage lesions of the knee are common and are being treated surgically with increasing frequency. While many studies have reported outcomes following a variety of cartilage restoration procedures, few have investigated outcomes of revision surgery after a failed attempt at cartilage repair or reconstruction.

Purpose

To investigate outcomes of revision cartilage restoration procedures for symptomatic articular cartilage lesions of the knee following a previously failed cartilage reconstructive procedure.

Study Design

Systematic review; Level of evidence, 4.

Methods

A literature search was performed by use of the PubMed, EMBASE, and MEDLINE/Ovid databases for relevant articles published between 1975 and 2017 that evaluated patients undergoing revision cartilage restoration procedure(s) and reported outcomes using validated outcome measures. For studies meeting inclusion criteria, relevant information was extracted.

Results

Ten studies met the inclusion criteria. Lesions most commonly occurred in the medial femoral condyle (MFC) (52.8%), with marrow stimulation techniques (MST) the index procedure most frequently performed (70.7%). Three studies demonstrated inferior outcomes of autologous chondrocyte implantation (ACI) following a previous failed cartilage procedure compared with primary ACI. One study comparing osteochondral allograft (OCA) transplant following failed microfracture (MFX) with primary OCA transplant demonstrated similar clinical outcomes and graft survival at midterm follow-up. No studies reported outcomes following osteochondral autograft transfer (OAT) or newer techniques.

Conclusion

This systematic review of the literature reporting outcomes following revision articular cartilage restoration procedures (most commonly involving the MFC) demonstrated a high proportion of patients who underwent prior MST. Evidence is sufficient to suggest that caution should be taken in performing ACI in the setting of prior MST, likely secondary to subchondral bone compromise. OCA appears to be a good revision treatment option even if the subchondral bone has been violated from prior surgery or fracture.

Shoulder activity level in patients with idiopathic adhesive capsulitis

BACKGROUND

Idiopathic adhesive capsulitis is a common condition resulting in painful multidirectional restriction of motion. Adhesive capsulitis may inhibit shoulder activity level, but this relationship has not been previously studied. This study tested the hypothesis that patients with idiopathic adhesive capsulitis have lower shoulder activity than sex- and age-matched controls.

METHODS

Seventy-two eligible patients (37 men and 35 women) with idiopathic adhesive capsulitis completed a validated shoulder activity scale that was compared with sex- and age-matched norms from a healthy population with no history of shoulder disorders. The association of shoulder activity level with patient age, sex, and American Shoulder and Elbow Surgeons and Simple Shoulder Test (SST) scores was evaluated.

RESULTS

Overall, 58% of patients actually had higher shoulder activity scores than sex- and age-matched controls. Among patients aged 51 to 70 years, 68% of patients (73% of men and 63% of women) demonstrated higher Shoulder Activity Scale scores compared with controls. The activity level was higher among all patients aged 51 to 70 years compared with controls (10.3 ± 1.48 vs. 8 ± 0.52, P = .0067). The difference was significant for men in this age group (12.2 ± 1.7 vs. 9 ± 0.75, P = .0042). There was a statistically significant positive correlation of the Shoulder Activity Scale score with the SST score (r = 0.31, P = .009).

CONCLUSION

Patients with idiopathic adhesive capsulitis do not have a lower shoulder activity level than sex- and age-matched controls, and older men may actually have a higher level of shoulder activity than controls. Shoulder activity level is correlated with the SST score in patients with idiopathic adhesive capsulitis.

The role for arthroscopic partial meniscectomy in knees with degenerative changes: a systematic review

AIMS

Patients with osteoarthritis of the knee commonly have degenerative meniscal tears. Arthroscopic meniscectomy is frequently performed, although the benefits are debatable. Recent studies have concluded that there is no role for arthroscopic washout in osteoarthritis of the knee. Our aim was to perform a systematic review to assess the evidence for the efficacy of arthroscopic meniscectomy in patients with meniscal tears and degenerative changes in the knee.

PATIENTS AND METHODS

A literature search was performed, using the PubMed/MEDLINE database, for relevant articles published between 1975 and 2015. A total of six studies, including five randomised controlled trials and one cross-sectional study of a prospective cohort, met the inclusion criteria. Relevant information including study design, operations, the characteristics of the patients, outcomes, adverse events and further operations were extracted.

RESULTS

The degree of osteoarthritis in the patients who were included and the rate of cross over from one form of treatment to another varied in the studies. Two randomised controlled trials showed a benefit of arthroscopic surgery in patients with limited degenerative joint disease, compared with conservative treatment. One cross-sectional study showed that patients with less severe degenerative changes had better outcomes.

CONCLUSION

Patients with symptomatic meniscal tears and degenerative changes in the knee can benefit from arthroscopic meniscectomy, particularly if the osteoarthritis is mild. A trial of conservative management may be effective and should be considered, especially in patients with moderate osteoarthritis. Cite this article: Bone Joint J 2016;98-B:934-8.

Immortalized Mouse Achilles Tenocytes Demonstrate Long-Term Proliferative Capacity While Retaining Tenogenic Properties

Investigating the cellular processes underlying tendon healing can allow researchers to improve long-term outcomes after injury. However, conducting meaningful studies to uncover the injury healing mechanism at cellular and molecular levels remains challenging. This is due to the inherent difficulty in isolating, culturing, and expanding sufficient primary tenocytes, due to their limited proliferative capacity and short lifespan. In this study, we sought to establish a novel line of immortalized mouse Achilles tenocytes (iMATs) with primary tenocyte properties, but increased proliferative capacity suitable for extensive in vitro experimentation. We show that isolated primary mouse Achilles tenocytes (pMATs) can be effectively immortalized using a piggyBac transposon expressing SV40 large T antigen flanked by FLP recombination target site (FRT). The resulting iMATs exhibit markedly greater proliferation and survival, which can be reversed with FLP recombinase. Furthermore, iMATs express the same set of tendon-specific markers as that of primary cells, although in lower levels, and respond similarly to exogenous stimulation with bone morphogenetic protein 13 (BMP13) as has been previously reported with pMATs. Taken together, our results suggest that iMATs acquire long-term proliferative capacity while maintaining tenogenic properties. We believe that iMATs are a suitable model for studying not only the native cellular processes involved in injury and healing, but also potential therapeutic agents that may augment the stability of tendon repair.

Thigh Injuries in American Football

Quadriceps and hamstring injuries occur frequently in football and are generally treated conservatively. While return to competition following hamstring strains is relatively quick, a high rate of injury recurrence highlights the importance of targeted rehabilitation and conditioning. This review describes the clinical manifestations of thigh-related soft-tissue injuries seen in football players. Two of these-muscle strains and contusions-are relatively common, while a third condition-the Morel-Lavallée lesion-is a rare, yet relevant injury.

Modified Protocol Decreases Surgical Site Infections after Total Knee Arthroplasty

We investigate the effectiveness of a comprehensive aseptic protocol in reducing surgical site infection (SSI) after knee arthroplasty in a single medical center with a high prevalence of MRSA. A database of all patients in a single center undergoing primary knee arthroplasty between 2005 and 2011 was reviewed for SSI using Centers for Disease Control criteria and AAOS guidelines. All patients were treated with an aseptic protocol consisting of the following: preoperative 2% mupirocin nasal ointment and 0.4% chlorhexidine surgical site wipes, modified instrument care, perioperative prophylactic vancomycin and cefazolin, and surgical site skin preparation with chlorhexidine, alcohol, and iodophor. We compare our protocol total knee arthroplasty SSI rate to our institutional historical control (2001-2004) and to contemporary literature. Among 1,224 patients, 70% were ASA class >2 and 64% had a body mass index (BMI) > 30 kg/m(2). We found an overall 0.49% infection rate, significantly lower than that of our institutional historical control (0.49 vs. 2.24%, p < 0.001; odds ratio [OR], 0.21; number needed to treat [NNT], 145) and seven recently published reports (p < 0.001-0.042; OR, 0.07-0.42). Compared with these reports, significantly more of our patients were ASA class > 2, BMI > 30 kg/m(2), immunosuppressed, or had rheumatoid arthritis. Our aseptic protocol decreases SSI in a high-risk population undergoing knee arthroplasty in a medical center and community with a high prevalence of MRSA.

Distinct effects of platelet-rich plasma and BMP13 on rotator cuff tendon injury healing in a rat model

BACKGROUND

Although platelet-rich plasma (PRP) is used clinically to augment tendon healing, bone morphogenetic protein-13 (BMP13) may provide a better therapeutic avenue to improve early tendon healing and repair.

HYPOTHESIS

Exogenous expression of BMP13 in tenocytes will up-regulate genes involved in tendon healing. Direct delivery of adenovirus-mediated BMP13 (AdBMP13) into the injured rat supraspinatus tendon will increase biomechanical properties.

STUDY DESIGN

Controlled laboratory study.

METHODS

Exogenous expression of BMP13 and the major growth factors in PRP (transforming growth factor-β1 [TGF-β1], vascular endothelial growth factor-A [VEGF-A], and platelet-derived growth factor-BB [PDGF-BB]) was accomplished by using recombinant adenoviral vectors. The expression of tendon- and matrix-associated genes in growth factor-treated tenocytes was analyzed by use of semiquantitative reverse-transcription polymerase chain reaction. A total of 32 rats with supraspinatus defect were divided into 4 groups and injected with adenovirus-containing green fluorescent protein (AdGFP; negative control), PRP, AdBMP13, or PRP+AdBMP13. All rats were sacrificed at 2 weeks after surgery, and tendons were harvested for biomechanical testing and histologic analysis.

RESULTS

BMP13 up-regulated type III collagen expression compared with AdGFP control and PRP growth factors (P < .01). BMP13 and PRP growth factors each up-regulated fibronectin expression (P < .01). There was an increase in stress to failure in each of the 3 treatment groups (P < .05 for PRP; P < .01 for AdBMP13 or PRP+AdBMP13) compared with AdGFP control. AdBMP13 demonstrated higher stress to failure than did the PRPs (P < .01). The addition of PRP did not increase the BMP13-enhanced stress to failure or stiffness. The biomechanical results were further supported by histologic analysis of the retrieved samples.

CONCLUSION

Exogenous expression of BMP13 enhances tendon healing more effectively than PRP as assessed by tendon- and matrix-associated gene expression, biomechanical testing, and histologic analysis.

CLINICAL RELEVANCE

While PRP is used in the clinical setting, BMP13 may be explored as a superior biofactor to improve rotator cuff tendon healing and reduce the incidence of retears.

Reversibly Immortalized Mouse Articular Chondrocytes Acquire Long-Term Proliferative Capability While Retaining Chondrogenic Phenotype

Cartilage tissue engineering holds great promise for treating cartilaginous pathologies including degenerative disorders and traumatic injuries. Effective cartilage regeneration requires an optimal combination of biomaterial scaffolds, chondrogenic seed cells, and biofactors. Obtaining sufficient chondrocytes remains a major challenge due to the limited proliferative capability of primary chondrocytes. Here we investigate if reversibly immortalized mouse articular chondrocytes (iMACs) acquire long-term proliferative capability while retaining the chondrogenic phenotype. Primary mouse articular chondrocytes (MACs) can be efficiently immortalized with a retroviral vector-expressing SV40 large T antigen flanked with Cre/loxP sites. iMACs exhibit long-term proliferation in culture, although the immortalization phenotype can be reversed by Cre recombinase. iMACs express the chondrocyte markers Col2a1 and aggrecan and produce chondroid matrix in micromass culture. iMACs form subcutaneous cartilaginous masses in athymic mice. Histologic analysis and chondroid matrix staining demonstrate that iMACs can survive, proliferate, and produce chondroid matrix. The chondrogenic growth factor BMP2 promotes iMACs to produce more mature chondroid matrix resembling mature articular cartilage. Taken together, our results demonstrate that iMACs acquire long-term proliferative capability without losing the intrinsic chondrogenic features of MACs. Thus, iMACs provide a valuable cellular platform to optimize biomaterial scaffolds for cartilage regeneration, to identify biofactors that promote the proliferation and differentiation of chondrogenic progenitors, and to elucidate the molecular mechanisms underlying chondrogenesis.

BMP9 signaling in stem cell differentiation and osteogenesis

Bone morphogenetic proteins (BMPs) are members of the TGF-β superfamily and play a critical role in skeletal development, bone formation and stem cell differentiation. Disruptions in BMP signaling result in a variety of skeletal and extraskeletal anomalies. BMP9 is a poorly characterized member of the BMP family and is among the most osteogenic BMPs, promoting osteoblastic differentiation of mesenchymal stem cells (MSCs) both in vitro and in vivo. Recent findings from various in vivo and molecular studies strongly suggest that the mechanisms governing BMP9-mediated osteoinduction differ from other osteogenic BMPs. Many signaling pathways with diverse functions have been found to play a role in BMP9-mediated osteogenesis. Several of these pathways are also critical in the differentiation of other cell lineages, including adipocytes and chondrocytes. While BMP9 is known to be a potent osteogenic factor, it also influences several other pathways including cancer development, angiogenesis and myogenesis. Although BMP9 has been demonstrated as one of the most osteogenic BMPs, relatively little is known about the specific mechanisms responsible for these effects. BMP9 has demonstrated efficacy in promoting spinal fusion and bony non-union repair in animal models, demonstrating great translational promise. This review aims to summarize our current knowledge of BMP9-mediated osteogenesis by presenting recently completed work which may help us to further elucidate these pathways.

The Current and Future Therapies for Human Osteosarcoma

Osteosarcoma (OS) is the most common non-hematologic malignant tumor of bone in adults and children. As sarcomas are more common in adolescents and young adults than most other forms of cancer, there are a significant number of years of life lost secondary to these malignancies. OS is associated with a poor prognosis secondary to a high grade at presentation, resistance to chemotherapy and a propensity to metastasize to the lungs. Current OS management involves both chemotherapy and surgery. The incorporation of cytotoxic chemotherapy into therapeutic regimens escalated cure rates from <20% to current levels of 65-75%. Furthermore, limb-salvage surgery is now offered to the majority of OS patients. Despite advances in chemotherapy and surgical techniques over the past three decades, there has been stagnation in patient survival outcome improvement, especially in patients with metastatic OS. Thus, there is a critical need to identify novel and directed therapy for OS. Several Phase I trials for sarcoma therapies currently ongoing or recently completed have shown objective responses in OS. Novel drug delivery mechanisms are currently under phase II and III clinical trials. Furthermore, there is an abundance of preclinical research which holds great promise in the development of future OS-directed therapeutics. Our continuously improving knowledge of the molecular and cell-signaling pathways involved in OS will translate into more effective therapies for OS and ultimately improved patient survival. The present review will provide an overview of current therapies, ongoing clinical trials and therapeutic targets under investigation for OS.

BMP signaling in mesenchymal stem cell differentiation and bone formation

Bone morphogenetic proteins (BMPs) are members of the TGF-β superfamily and have diverse functions during development and organogenesis. BMPs play a major role in skeletal development and bone formation, and disruptions in BMP signaling cause a variety of skeletal and extraskeletal anomalies. Several knockout models have provided insight into the mechanisms responsible for these phenotypes. Proper bone formation requires the differentiation of osteoblasts from mesenchymal stem cell (MSC) precursors, a process mediated in part by BMP signaling. Multiple BMPs, including BMP2, BMP6, BMP7 and BMP9, promote osteoblastic differentiation of MSCs both in vitro and in vivo. BMP9 is one of the most osteogenic BMPs yet is a poorly characterized member of the BMP family. Several studies demonstrate that the mechanisms controlling BMP9-mediated osteogenesis differ from other osteogenic BMPs, but little is known about these specific mechanisms. Several pathways critical to BMP9-mediated osteogenesis are also important in the differentiation of other cell lineages, including adipocytes and chondrocytes. BMP9 has also demonstrated translational promise in spinal fusion and bone fracture repair. This review will summarize our current knowledge of BMP-mediated osteogenesis, with a focus on BMP9, by presenting recently completed work which may help us to further elucidate these pathways.