Citations

Objectives: The purpose of this study is to evaluate the effect of low-intensity blood flow restriction (LI- BFR) training utilized in a pre-rehabilitative setting for patients undergoing anterior cruciate ligament reconstruction (ACLR) on postoperative outcomes by minimizing postoperative atrophy and impairment of the quadriceps. We hypothesize that postoperative strength and hypertrophy of the quadriceps will be greater in a population that undergoes preoperative LI-BFR training than that of a population that undergoes low-intensity sham control (LI-SHAM) training. Methods: Twenty-eight subjects undergoing primary ACLR underwent 2 weeks of either a BFR intervention or a SHAM intervention at a rate of 2 sessions per week before surgery. Quadriceps strength and cross-sectional area were measured as well as other exploratory outcomes were measured before and after the intervention before surgery and at 5 different time points after surgery, through 6 months postoperative. Quadriceps strength was assessed through handheld dynamometry and a leg press test and quadriceps cross-sectional area was assessed using musculoskeletal ultrasound imaging. Results: Adjusting for sex, time, and strength/hypertrophy at baseline, there were no significant differences found between treatment groups for the primary endpoints. Compared to 24-48 hours pre- op, this suggests that the post-op average hypertrophy remains significantly lower through 24 weeks post-op, while leg strength is similar at 24 weeks post-op as measured by handheld dynamometer and even significantly larger at 24 weeks as measured by the leg press test. Conclusions: A 2-week preoperative program of LI-BFR training may not be effective to improve postoperative quadriceps strength and hypertrophy after ACLR.

Objectives: The purpose of this study was to assess return to play (RTP), patient-reported outcomes (PRO), and reoperation rates following patellofemoral stabilization surgeries (PSS) for recurrent patellar instability (RPI) in a cohort of competitive wrestlers. Methods: All competitive wrestlers with a history of an RPI and subsequent PSS at a single institution between 2000 and 2020 were identified. Primary PSS ranged from MPFL reconstruction (n = 31; 50%) or MPFL repair (n = 22; 33.5%), and other PSS (n = 9; 14.5%) in the form of tibial tubercle osteotomy (TTO), lateral retinaculum release (LRR), and medial retinaculum reefing (MRR). Exclusion criteria included revision PSS, or concomitant anterior cruciate ligament reconstruction or multi ligament knee injury. All patients were contacted for determination of reinjury rates, current sport status, and PROs. Surgical failure defined as subsequent patellar dislocation despite operative management or need for secondary PSS. Results: Ultimately, 62 knees in 56 wrestlers were included at a mean follow-up time of 6.6 years (range, 2.0 – 18.8 years). RTP occurred in 55.3% of wrestlers at a mean of 8.8 ± 6.7 months. Among the PSS no differences were observed between rates of RTP (P = .676), postoperative pain (P = .176), Tegner activity level (P = .801), International Knee Documentation Committee (P = .378), Lysholm (P = .402), or Kujala scores (P = .370). Recurrent patellar instability was the most common complication in 21% of knees. Among PSS types, MPFL reconstruction had the lowest rate of RPI (6.5% vs. 27.3% vs. 55.6%; P = .005), and surgical failure (9.7% vs. 31.8% vs. 55.6%; P = .008). Kaplan-Meier survivorship free from surgical failure of the entire cohort was 91.9% at 1 year, 77.7% at 5 years, and 65.7% at 15 years. MPFL reconstruction had the highest survivorship when compared to MPFL repair and other PSS up to 10 years after the index surgery (90.3% vs. 64.1% vs. 27.8%; P = .048). Conclusions: Recurrent patellar instability remains a concern for competitive wrestlers after PSS. MPFL reconstruction may serve as a more durable surgical treatment option with lower rates of RPI and failure when compared to other PSS up to 10 years after surgery. [Table: see text]

Objectives: Meniscal root tears have been shown to accelerate cartilage breakdown and increase the risk of total knee arthroplasty (TKA) if left unaddressed. Unfortunately, many patients with meniscal root tears already have associated chondromalacia which can impact surgical outcomes. The presence of advanced chondromalacia in the medial or lateral compartmentsof the knee is a known contraindication to performing meniscal root repair; however, the effect of advanced patellofemoral chondromalacia on meniscal root outcomes is not known. The purpose of this study was to compare the outcomes of meniscal root repair in patients with and without advanced patellofemoral chondromalacia (PFC). Methods: A retrospective review of prospectively collected data of patients undergoing meniscal root repair by a single surgeon was conducted between January 2016 and December 2019. Patients were included if they had undergone an isolated posterior medial or lateral meniscal root repair. The meniscal root repair was performed using a transtibial suture technique. Patients were placed into one of two groups depending on the amount of patellofemoral chondromalacia present at the time of surgery. Patients with Outerbridge grade 0-2 were placed in the Minimal Patellofemoral Chondromalacia (MPFC) Group. Patients with Outerbridge 3-4 changes found the time of surgery were placed in the Patellofemoral Chondromalacia (PFC) Group. Patients with Outerbridge 3-4 changes found in the medial or lateral compartment were excluded from the study. Lysholm Knee Scoring Scale and the International Knee Documentation (IKDC) Subjective Knee Form were collected preoperatively, 6,12 and 24 months after surgery. Clinical outcomes followed included recurrent meniscal tear, conversion to total knee arthroplasty, knee arthrofibrosis requiring manipulation under anesthesia/lysis of adhesions and infection. PASS and MCID were determined using data on meniscal repairs in other literature. Continuous data was compared using two-tailed student-T test while categorical data was compared utilizing chi-square testing. Results: A total of 27 patients made up the PFC group and 54 in the MPFC group. There was no difference between the groups with regards to age, sex, BMI or laterality of the procedure. The PFC group had 26 medial and 1 lateral meniscal root repairs. The MPFC group had 51 medial and 3 lateral repairs. The average Outerbridge score of the patella for the PFC group was 3.2 compared to 1.8 in the MPFC group (p<.001). The Outerbridge score for the trochlea in each group was 3.4 vs. 1.6 for the PFC and MPFC groups respectively (p<.001). No difference was identified between the Outerbridge score for the medial compartment for the PFC and MPFC groups (1.48 vs 1.46 respectively) or the lateral compartments (0.48 vs. 0.61 respectively). Lysholm and IKDC scores rose significantly over the pre- operative value at all time points in the study for both groups. No difference was seen between the two groups for the Lysholm or IKDC scores at any timepoint during study. PASS rates for IKDC between the two groups were similar with 6,12 and 24-month PASS rates being 66.7%, 87.5% and 81.4% respectively for the PFC group and 62.9%, 77.8% and 85.2% for the MPFC group. There was also no difference between the groups with regards to the percentage of patients reaching MCID for IKDC. The PFC group showed the percentage of patients reaching MCID to be 81.5%, 100% and 92.6% at the 6,12, and 24 month time points respectively while the MPFC group showed the percentage of patients reaching MCID to be 75.9%, 88.9% and 94.4% at the 6,12 and 24 month postoperative time points respectively. There was 1 (3.7%) recurrent tear in the PFC group and 3 (5.6%) in the MPFC group (p=.72). One patient (3.7%) in the PFC and none of the MPFC group were converted to TKA by the 2-year follow up (p=.15). Each group had 1 patient develop arthrofibrosis requiring MUA/LOA. There were no infections in the PFC group and one in the MPFC group which was a superficial wound infection that resolved after a course of oral antibiotics. Conclusions: In our series, the presence of advanced patellofemoral chondromalacia did not lead to inferior short-term outcomes in patients undergoing meniscal root repair compared to patients without patellofemoral chondromalacia. IKDC and Lysholm scores were similar between the PFC and MPFC group at all time points while scores for both groups were significantly higher than preoperative levels at all time points. The ability to reach MCID and PASS for IKDC was not significantly different between the two groups. In addition, there was not a significant difference between the two groups in the number of recurrent tears, conversion to total knee arthroplasty or complications identified. Our results show meniscal root repair can be performed in patients with severe patellofemoral chondromalacia with similar results as patients undergoing root repair without severe patellofemoral chondromalacia. Patellofemoral chondromalacia should not be considered a contraindication to meniscal root repair.

Objectives: Ulnar Collateral Ligament (UCL) tears are common in baseball players. When non-operative management fails; reconstruction or repair may be necessary to restore physical function. There is no clear consensus regarding the indications for surgery based on magnetic resonance imaging (MRI) tear characteristics, or the indications for selecting repair over reconstruction. The purpose of this study was to define the indications for UCL surgery based on MRI and to elucidate indications for UCL repair vs reconstruction. Methods: Twenty-six orthopaedic surgeons who treat baseball players were surveyed. Forty-five MRIs were reviewed: 15 without UCL tears, 15 with intra-operatively confirmed partial-thickness tears, and 15 with full-thickness tears. Factors investigated included ligament characteristics (peri-ligamentous or osseous edema, ligament hypertrophy, calcification, partial or full-thickness tearing) and location (proximal, mid-substance, or distal). Surgeons were given a clinical scenario and asked whether 1) surgery was indicated and 2) whether repair or reconstruction was recommended. Odds ratios (OR) and 95% confidence intervals (95%CI) helped identify significant predictors for both queries. Results: The odds of recommending surgical treatment compared to non-operative treatment were 2.4x more likely for a proximal partial-thickness tear, 3.2x for distal partial-thickness tear, 5.1x for distal full- thickness tear, and 7.0x for proximal full-thickness tear (p<0.001). Significant indications for repair included distal partial (OR=1.6, 95%CI 1.0, 2.1, p<0.001) and full-thickness tears (OR=1.7, 95%CI 1.1, 2.3, p<0.001). Repair was 3x less likely recommended for mid-substance full-thickness tears (OR=3.0, 95%CI - 5.0, -1.0, p=0.004). Ultrasound stress testing was requested in 78% of partial tears. Conclusions: Among surgeons surveyed, the highest odds for recommending operative treatment were proximal full-thickness tears, then distal full-thickness, distal partial-thickness, and proximal partial- thickness tears. Repair was most appropriate for partial and full-thickness distal tears, but relatively contraindicated for complete mid-substance UCL tears. Ultrasound stress testing was frequently requested for partial tears. Given the lack of consensus among surgeons, future prospective registries are necessary to determine whether these factors associate with clinical outcomes. [Table: see text]

Objectives: Baseball pitchers often participate in throwing programs that involve throwing at reduced effort levels to gradually increase the amount of stress experienced across the elbow. It is currently unknown how reduced effort pitching compares to maximum effort with respect to elbow stress and ball velocity. The purpose of this study is to determine whether elbow stress and ball velocity correlate with reduced effort pitching, whether elbow stress and ball velocity decrease proportionally while throwing at a reduced effort, and to assess intrathrower reliability. Methods: Ten healthy male high school baseball pitchers threw 5 pitches from a regulation pitching mound at 3 effort levels: maximum effort, 75% effort, and 50% effort. Elbow stress, specifically elbow varus torque, was calculated for all pitches using a marker-based 3D motion capture system. Ball velocity was measured using a Doppler radar gun. Intrathrower variability was calculated for each effort level. Results: Elbow stress and ball velocity decreased with reduced effort throws (p<0.001 and p=0.003, respectively). However, the reductions in elbow stress and ball velocity were not proportional. At 75% effort throws, elbow stress decreased only 19% and ball velocity decreased only 10%. At 50% effort throws, elbow stress decreased only 25% and ball velocity decreased only 15%. Intrathrower reliability was excellent for elbow stress and ball velocity, with intraclass correlation coefficients all greater than or equal to 0.80. Conclusions: Pitching at a reduced effort level resulted in decreased elbow stress and ball velocity. However, for every 25% reduction in perceived effort, elbow stress decreased by a mean of 13% and ball velocity decreased 8%. When baseball pitchers attempt to throw at a reduced effort of maximum, throwing metrics do not decrease proportionately. While pitching at a reduced effort of maximum decreases elbow stress and ball velocity, the decrease is not proportional, subjecting the elbow to more stress than intended. This has significant clinical importance to pitchers, coaches, and medical professionals in the setting of injury prevention and return to sport. [Table: see text]

Objectives: While pitch count and rest guidelines have been promoted for youth and adolescent baseball players for nearly two decades, compliance with guidelines remains poorly understood. The purpose of this study was to determine the frequency of compliance with Pitch Smart guidelines, as well as the association between compliance and range of motion, strength, velocity, injury, and pitcher utilization. Methods: This study was a prospective, multi-center study of high school pitchers, encompassing each region of the United States. Pre-season pitchers were surveyed about their compliance with current off- season rest-related guidelines and history of injury. Pre-season, pitchers underwent standardized physical examinations and pitch velocity was measured. During the high school season that followed, both pitch counts and injury incidence were collected. Results: One hundred and fifteen pitchers participated. Based upon pre-season data, 84% of pitchers had previously violated current pitch recommendation guidelines. During the season, 14% had at least one instance of a violation of the current pitch counts guidelines. Across both the pre-season survey and in-season pitch counts, 89% of players had at least one violation of the current Pitch Smart guidelines. While there were no significant differences in range of motion or strength, those pitchers who were non-compliant with guidelines in the pre-season had higher max pitch velocity (mean±standard deviation 74±8 miles per hour vs. 69±5 miles per hour, p=0.009). Pitchers self-reported their peak velocity at 7 MPH greater than the actual measured velocity. Only a single injury occurred during the season, precluding a comparison between groups. There were no significant differences in the incidence of a history of injury between those pitchers who were noncompliant with between-season rest guidelines (p=0.285). Conclusions: Most high school pitchers are non-compliant with current Pitch Smart guidelines, and they tend to overestimate their peak velocity by 7 MPH. Pitchers with greater velocity were at the highest risk for violating current pitch count recommendations. Since both increased throwing volume and pitch velocity are known risk factors for injury, these athletes may be at particular risk for subsequent injury. research is necessary to understand whether taking three consecutive month rest between seasons prevents pitching-related injury.

Objectives: To describe outcomes of posterior capsular release to treat knee extension deficits after anterior cruciate ligament (ACL) reconstruction in athletes. Methods: A retrospective review was performed between January 2014 and December 2019 for patients undergoing arthroscopic posterior capsular release for knee extension loss following ACL reconstruction. Patients were indicated for the procedure if they had greater than 10° of extension loss at least three months after ACL reconstruction that was refractory to physical therapy. Patients were included in the study if they were involved in either high school or college athletics, had complete outcomes of interest, and had at least two years of follow up. Collected outcomes included preoperative and postoperative measurement of knee extension, international knee documentation committee (IKDC) score, Lysholm score, return to sport data, and complications. Results: Over the study period a total of 38 arthroscopic posterior capsular releases were performed. Of these, 20 were high school or college athletes. Two of these patients did not have 2-year follow up, leaving a total of 18 patients included in the analysis. Patients underwent surgery at an average of 16 weeks after ACL reconstruction. Knee extension improved an average of 13.8° at 2-years follow up (pre- release extension deficit 15.1°, post-release extension deficit 1.3°, p < 0.005). Improvements in the IKDC score averaged 21.7 at 6 months and 35.0 at 24 months, both of which were statistically significant (p < 0.001). Similarly, differences in Lysholm included a significant improvement of 23.0 and 34.2 at 6 months and 2 years, respectively (p < 0.001). In total, 77.8% returned to sport at an average of 9.8 months from their primary surgery and 6.5 months following posterior capsular release surgery. Complications included one patient that required revision capsular release for persistent extension loss, one ACL tear of the ipsilateral knee, and two ACL tears of the contralateral knee. No infections or neurovascular injuries occurred. Conclusions: Knee extension loss after ligamentous repair surgery can have significant consequences including diminished patient satisfaction, reduced return to sport, and an increased risk of osteoarthritis development. Although arthroscopic posterior capsular release is a recognized treatment for knee extension loss, outcomes have not been reported in athletes. In our series, arthroscopic posterior capsular release resulted in significant improvement of knee extension and patient reported outcome scores at 6 month and 2 years postoperatively. Additionally, the procedure appears to be safe with few complications and only 5.6% of patients requiring repeat arthroscopy for knee extension loss. Posterior capsular release appears to be a reliable and safe treatment for athletes with persistent knee extension loss after ACL reconstruction.

Objectives: Augmentation of rotator cuff repair in patients at risk for retear has gained popularity. These techniques have generally consisted of allograft and xenograft patches. Recently, use of an autograft biceps from the normally discarded portion after biceps tenodesis was described as a potential patch for rotator cuff repair augmentation. As an autograft, it is free and readily available. The original description prepared the patch by placing it through a commercial skin graft preparation station. This technique results in a significant decrease in tenocyte viability, however, and results in a patch that is difficult to work with. Recently, an autograft compression plate has been employed to use as a point of care processor for adapting the discarded long head of the biceps after tenodesis into an autograft patch. The purpose of this study was to evaluate the feasibility of this point of care graft preparation method, and to specifically evaluate its effect on tenocyte viability in patients undergoing patch augmentation for rotator cuff repair. Methods: We reviewed the medical records of consecutive patients who underwent biceps tenodesis for either rotator cuff repair or anatomic shoulder arthroplasty. After tenodesis, and after 27 mm of the long head of the biceps was secured for compression into the patch, the remaining length of normally discarded tendon was longitudinally split, resulting in 2 equal lengths of remnant tendon from the same zone of the tendon. One sample was sent to pathology with no preparation, and the other was prepared as a biceps autograft patch using the autograft compression plate according to the manufacturer’s recommendations. Once prepared, this second biceps sample was sent to pathology along with the first. The request was to evaluate for tenocyte viability. Pathologists were not told which sample was compressed. Records were reviewed to determine if biceps tendon samples were viable at the time of harvest, and whether the compression process affected a change between the first and second specimen. Results: 20 consecutive patients were reviewed. All 20 biceps produced usable patches. The remnant biceps samples that were sent to pathology revealed the following: Sixteen of the 20 patients had biceps tenocyte viability that were read out as completely normal in both the compressed and non compressed samples. Of the 4 patients that did show some degree of tenocyte necrosis or death, 3 of the patients had identical findings between the compressed and non-compressed samples. Only 1/20 (5%) of the patients showed a difference between the compressed sample and the non-compressed sample, with the compressed sample demonstrating small areas of “patchy necrosis” while the non compressed sample showed normal tendon in that specimen. Conclusions: Compression of the long head of the biceps results in an autograft patch that is a promising option in rotator cuff augmentation. The method of compression plating to process the long head of the biceps remnant into an augmentation patch appears to have no significant effect on tenocyte viability, suggesting that the patch has live tenocytes at the time of point of care augmentation.

Objectives: An increased posterior tibial slope (PTS) corresponds with an increased risk of graft failure following anterior cruciate ligament reconstruction (ACLR). Validated methods of human PTS measurements are subject to interobserver variability and can be inefficient on large-scale sets of images. The purpose of this study is to develop a deep learning artificial intelligence technique for the automated measurement of PTS from standard lateral knee radiographs. Methods: A deep learning U-Net model was developed on a cohort of 300 postoperative short leg lateral radiographs from ACLR patients to segment the tibial shaft, tibial joint surface, and tibial tuberosity. The model was trained via a random split following an 80:20 train-validation scheme. Masks for training images were manually segmented and the model was trained for 400 epochs. An image processing pipeline was then deployed to annotate and measure the PTS using the predicted segmentation masks. Finally, the performance of this combined pipeline was compared to human measurements performed by two study personnel using a previously validated manual technique for measuring PTS on short leg lateral radiographs on an independent test-set consisting of both preoperative and postoperative images. Results: The U-Net semantic segmentation model achieved a mean Dice similarity coefficient of 0.885 on the validation cohort. The mean difference between human-made and computer-vision measurements was 1.92⁰ (σ = 2.81⁰, P=0.24). Extreme disagreements between human and machine measurements as defined by differences ≥5⁰ occurred less than 5% of the time. The model was incorporated into a web based digital application for demonstration purposes which can provide measurement of an uploaded image in portable network graphics format in less than 5 seconds. Conclusions: We developed an accurate and reliable deep learning computer vision algorithm to automate the measurement of PTS on lateral knee radiographs. This tool will be deployed for clinical use on an institution-wide basis and, pending external validation, be made available to outside orthopaedic surgeons. This will provide an efficient and accurate tool to measure PTS during the preoperative assessment of ACL-injured patients.

Objectives: Desirable outcomes following surgery for anterior shoulder instability (ASI) include a multitude of functional and clinical functions, yet it remains uncertain if all of these outcomes are simultaneously achievable (i.e. can patients have full motion and no instability; does excellent stability coincide with stiffness?). The purpose of this study was to employ unsupervised machine learning techniques to define the actual "optimal observed outcome” for patients undergoing surgical treatment for ASI and to identify predictors of obtaining this outcome. Methods: Patients <40 years with an initial diagnosis of ASI from 1994 -2016 were included. Four unsupervised machine learning clustering algorithms were evaluated to partition subjects into “optimal observed outcome” or “suboptimal outcome” based on combinations of actually observed outcomes. Demographic, clinical, and treatment variables were compared between groups using descriptive statistics and Kaplan-Meier survival curves; multivariate stepwise logistic regression evaluated variable prognostic value. Results: 200 patients with a mean follow-up of 11 years were included. 146 (64%) obtained the “optimal observed outcome”, characterized by significantly (P <0.001) lower rates of: recurrent postoperative pain (23% vs 52%), recurrent instability (12% vs 41%), revision surgery (10% vs 24%), progression to osteoarthritis (OA) (5% vs. 19%), and mildly restricted motion (161° vs. 168°). Stepwise multivariate logistic regression identified time from initial instability to presentation (OR: 0.96, 95% CI: 0.92-0.98) and habitual instability (OR: 0.17, 95%CI: 0.04-0.77) as negative predictors of “observed optimal outcome”. Increased rate of subluxation over frank dislocation pre-operatively (OR: 1.30, 95% CI: 1.02-1.65) was a positive predictor. Type of surgery performed was not a significant predictor. Conclusions: Following surgical treatment for ASI, an appropriate “optimal observed outcome” can be defined as: minimal postoperative pain, absence of recurrent instability, low rates of revision surgery, absence of OA, and increased ROM. This “optimal observed outcome” was achieved in over 2/3rds of the cohort and this work demonstrated the synergistic relationship of these. The most significant predictors included shorter time to presentation and history of subluxations over frank dislocations pre-operatively. This definition of the “optimal observed outcome” may be more appropriate for surgical decision making and setting appropriate expectations. [Table: see text][Table: see text]