Preoperative corticosteroid injections are associated with a higher periprosthetic infection rate following primary total shoulder arthroplasty: A systematic review and meta-analysis.

BACKGROUND: Corticosteroid injections (CSI) are commonly used for the treatment of shoulder pain in patients with osteoarthritis (OA) and rotator cuff arthropathy (RCA). These injections may increase the risk of infection following eventual shoulder arthroplasty. PURPOSE: The purpose of this study was to perform a systematic review and meta-analysis of existing data to explore the relationship between preoperative CSI's and postoperative periprosthetic joint infection (PJI) following shoulder arthroplasty. METHODS: A literature search was performed on PubMed, Embase, and Web of Science databases through September 29, 2023. Of the 4,221 retrieved, 7 studies including 136,233 patients were included for qualitative analysis. Studies describing patients receiving CSI prior to shoulder arthroplasty and the effect on postoperative infection risk were included in the systematic review and subsequent meta-analysis. Assessment of risk of bias was performed using the Methodological Index for Non-Randomized Studies (MINORS) criteria. RESULTS: Receiving a corticosteroid injection prior to shoulder arthroplasty was found to have a statistically significant association with increased risk for PJI (OR: 1.13. 95%; CI: 1.06-1.19; p < 0.0001). The rate of PJI increased when injections were given closer to the time of surgery. Patients who received an injection at any time point before surgery had a 5.4% risk of PJI compared to 7.9% and 9.0% in patients receiving an injection within 3 months and 1 month of surgery respectively. This time dependent association however did not reach statistical significance: 1 month OR 1.48; 95% Cl: 0.86-2.53; p = 0.16, 3 months OR 1.95; 95% Cl: 0.95-4.00; p = 0.07. CONCLUSION: The results of this systematic review and meta-analysis demonstrate that patients receiving corticosteroid shoulder injections prior to shoulder arthroplasty may be at an increased risk for prosthetic joint infection postoperatively. While time dependent stratification did not reach statistical significance, our findings indicate a clear trend of increased risk for patients receiving injections closer to surgery.

Two Intramedullary and 1 Extramedullary Cortical Button, With or Without Interference Screw, Show Biomechanical Properties Superior to Native Tendon in Repair of the Distal Biceps Tendon: A Systematic Review and Network Meta-analysis of Biomechanical Performance.

PURPOSE: The aim of this study was to use a systematic review and network meta-analysis (NMA) to compare the failure strength, maximum strength, stiffness, and displacement of available constructs for distal biceps repair. METHODS: An NMA was conducted to determine the performance of 2 all-suture suture anchors (2x ASA), 2 intramedullary cortical buttons (2x IM CB), 2 suture anchors (2x SA), extramedullary cortical buttons (EM CB), extramedullary cortical button plus interference screw (EM CB+IFS), interference screw (IFS), single intramedullary cortical button (IM CB), single suture anchor (SA), transosseous suture (TOS), tension slide technique (TST), and tension slide technique plus suture tape (TST+ST). Analysis consisted of arm-based network meta-analysis under Bayesian random-effects model with Markov Chain Monte Carlo (MCMC) sampling. Biomechanical outcomes were summarized as treatment effects and their corresponding 95% confidence intervals (CI). Rank probabilities were calculated and used to generate each treatment's surface under the cumulative ranking (SUCRA) curve. Biomechanical properties were compared to native tendon. Displacement >10 mm was defined as clinical failure. RESULTS: Twenty-one studies were included. For failure strength, no construct outperformed the native tendon but 2× SA, IFS, SA, and TOS demonstrated poorer failure strength. For the maximum load to failure, EM CB+IFS outperformed the native tendon. Compared to native tendon, EM CB+IFS, EM CB, and 2×IM CB were stiffer, while 2x SA and IFS were less stiff. No construct demonstrated >10 mm of displacement, but constructs with displacement above the mean (3.5 mm) included 2× ASA, 2xIM CB, and TOS. CONCLUSIONS: The fixation constructs that consistently demonstrated comparable or better biomechanical properties (failure strength, maximum strength, and stiffness) to native tendon in distal biceps tendon repair were the extramedullary cortical button with or without interference screw and two intramedullary cortical buttons. No construct demonstrated displacement beyond standard definitions for clinical failure. CLINICAL RELEVANCE: This network meta-analysis of biomechanical studies suggests that extramedullary cortical button and two intramedullary cortical buttons may be the most stable construct for distal biceps repair fixation, with equivalent or better biomechanical properties compared to native tendon.

Editorial Commentary: Axial Stress Examination Under Anesthesia Provides a Highly Reliable Test for Measurement of Hip Distraction.

Symptomatic hip microinstability is now recognized as one of the most common surgical indications for revision hip arthroscopy. Hip microinstability can be difficult to diagnose, particularly because of the multifactorial etiology and limited physical examination maneuvers that provide objective testing of gross hip stability. One measure of hip stability is axial stability evaluated under traction intraoperatively. Recent research has suggested that average axial stability of the hip is decreased after primary hip arthroscopy-although not in all cases. Recognizing that there are many additional factors that may contribute to hip microinstability, as well as the fact that axial stability is only one assessment of overall stability of the hip, is important in the evaluation of microinstability in the setting of prior hip arthroscopy.

The Effect of Rim Preparation, Labral Augmentation, and Labral Reconstruction on the Suction Seal of the Hip.

PURPOSE: To evaluate the biomechanical properties of the labral suction seal in the native labrum and after rim preparation, labral augmentation, and labral reconstruction. METHODS: Eight hemi-pelvises were dissected to the level of labrum and mounted for biomechanical testing. Each specimen was tested in axial distraction starting with the native labrum and then sequentially following rim preparation from 12 to 3 o'clock, labral augmentation, and segmental labral reconstruction using the iliotibial band allograft. In each condition, the specimens were compressed to 250 N and then distracted at 10 mm/s with force and displacement continuously recorded. Each test was repeated 3 times, and the mean peak force, displacement at peak force, and work were calculated. Data were reported as a percentage of the intact values to account for sex and size differences. Statistical testing was performed via a repeated-measures analysis of variance with a post hoc Tukey analysis. RESULTS: Peak loads occurred within 2.21 to 3.11 mm of displacement. The mean peak force, displacement at peak force, and work relative to the intact condition were the following: rim preparation (91.1% ± 8.5%, 94.4% ± 14.3%, 93.4% ± 23.5%, respectively), augmentation (66.1% ± 27.6%, 78.2% ± 16.3%, 55.7% ± 30.7%, respectively), and reconstruction (55.6% ± 25.7%, 64.7% ± 31.4%, 38.7% ± 27.2%, respectively). There was no significant difference in peak force following the rim preparation (P = .807), but peak force was significantly decreased after augmentation and reconstruction (P = .010 and P < .001, respectively). There was no significant difference in displacement at peak force following rim preparation or augmentation (P = .936 and P = .125, respectively), but displacement at peak force was significantly decreased after reconstruction (P = .005). The work from the suction seal was significantly less in both augmentation and reconstruction states compared to the intact labrum (P = .004 and P < .001, respectively) and rim preparation (P = .017 and P < .001, respectively). CONCLUSIONS: The results show that the suction seal is not significantly changed following rim preparation. Relative to the rim preparation, labral augmentation may re-create the labral suction seal better than labral reconstruction. CLINICAL RELEVANCE: This study provides a biomechanical basis for surgical decision making and clinical management of patients with labral tears of the hip.

Physical Therapy Combined With Subacromial Cortisone Injection Is a First-Line Treatment Whereas Acromioplasty With Physical Therapy Is Best if Nonoperative Interventions Fail for the Management of Subacromial Impingement: A Systematic Review and Network Meta-Analysis.

PURPOSE: To construct an algorithm to optimize clinical outcomes in subacromial impingement based on current, high-level evidence. METHODS: A systematic review of all clinical trials on subacromial impingement published from 1999 to 2020 was performed. Demographic, clinical, range of motion (ROM), and patient-reported outcome measure (PROM) data were collected. Interventions were compared via arm-based Bayesian network meta-analysis in a random-effects model and treatments ranked via surface under the cumulative ranking curves with respect to 3 domains: pain, PROMs, and ROM. RESULTS: A total of 35 studies comprising 3,643 shoulders (42% female, age 50 ± 5 years) were included. Arthroscopic decompression with acromioplasty ranked much greater than arthroscopic decompression alone for pain relief and PROM improvement, but the difference in absolute PROMs was not statistically significant. Corticosteroid injection (CSI) alone demonstrated inferior outcomes across all 3 domains (pain, PROMs, and ROM) with low cumulative rankings. Physical therapy (PT) with CSI demonstrated moderate-to-excellent clinical improvement across all 3 domains whereas PT alone demonstrated excellent ROM and low-moderate outcomes in pain and PROM domains. PT with nonsteroidal anti-inflammatory drugs or alternative therapies ranked highly for PROM outcomes and moderate for pain and ROM domains. Finally, platelet-rich plasma injections demonstrated moderate outcomes for pain, forward flexion, and abduction with very low-ranking outcomes for PROMs and external rotation. CONCLUSIONS: Arthroscopic decompression with acromioplasty and PT demonstrated superior outcomes whereas CSI demonstrated poor outcomes in all 3 domains (pain, PROMs, and ROM). For patients with significant symptoms, the authors recommend PT with CSI as a first-line treatment, followed by acromioplasty and PT if conservative treatment fails. For patients with symptoms limited to 1 to 2 domains, the authors recommend a shared decision-making approach focusing on treatment rankings within domains pertinent to individual patient symptomatology. LEVEL OF EVIDENCE: I, systematic review and network meta-analysis of Level I studies.

Two-Year Clinical Outcomes and Survivorship After Isolated Biceps Tenodesis.

PURPOSE: The purpose of this study was to evaluate clinical outcomes and survivorship of isolated biceps tenodesis (BT) at a minimum of 2 years and to identify patient-specific factors associated with these outcomes in patients undergoing BT without concomitant rotator cuff repair (RCR). We hypothesized that patient-reported outcomes would be significantly improved on American Shoulder and Elbow Surgeons Survey (ASES) and Single Assessment Numeric Evaluation (SANE), with a high rate of survivorship (>90%) at 2-year follow-up. METHODS: A retrospective review of an institutional registry was performed to identify patients who underwent BT from July 2016 to December 2017. Patients >18 years old who underwent an open or arthroscopic BT procedure using an interference screw, button, or anchor for underlying bicipital pathology, without a concomitant RCR or shoulder arthroplasty, and were a minimum of 2 years postoperative were included. Patients were administered ASES and SANE questionnaires preoperatively and at final follow-up. Survivorship was evaluated using Kaplan-Meier analysis. Failure was defined as any patient who underwent reoperation related to the index surgery. RESULTS: A total of 110 patients (mean ± standard deviation age, 48.60 ± 12.14 years) who underwent isolated BT with a follow-up of 24.90 ± 3.95 months were included in analysis. There was a significant improvement in ASES and SANE at final follow-up (P < .001), with 81% to 84% of patients achieving minimal clinically important difference (MCID), 72% to 82% achieving substantial clinical benefit (SCB), and 72% to 80% achieving patient-acceptable symptom state (PASS). Worker's Compensation (WC) patients had a decreased likelihood of achieving PASS on ASES (P = .015) and SANE (P = .012). Four cases were deemed failures (3 revision BTs and 1 capsular debridement) at 15.09 ± 9.57 months. WC did not have a significant effect on likelihood of BT failure. CONCLUSION: Biceps tenodesis provided significant clinical improvement and high rates of survivorship 2 years postoperatively. WC was associated with a decreased likelihood of achieving PASS. These results support the continued use of isolated BT for treating biceps pathology. LEVEL OF EVIDENCE: IV, case series.

Double-Row Repair With Platelet-Rich Plasma Optimizes Retear Rates After Small to Medium Full-Thickness Rotator Cuff Repair: A Systematic Review and Network Meta-analysis of Randomized Controlled Trials.

PURPOSE: To compare the different interventions described in the literature for the surgical treatment of small and medium complete rotator cuff tears. METHODS: A systematic review of randomized controlled trials of small-medium, full-thickness rotator cuff tears published since 2000 was performed. Clinical characteristics, re-tear rates, range of motion (ROM), and patient-reported outcomes (PRO) data were collected. Interventions were compared via arm-based Bayesian network meta-analysis in a random-effects model. Interventions were ranked for each domain (re-tear risk, pain, ROM, and PROs) via surface under the cumulative ranking curves. RESULTS: A total of 18 studies comprising 2046 shoulders (47% females, mean age 61 ± 3 years, mean follow-up 21 ± 5 months) were included. Interventions that ranked highest for minimizing re-tear risk included arthroscopic single-row repair (A+SR) or double-row repair (A+DR) with or without platelet-rich plasma (PRP). Open repair and A+SR repair with acromioplasty (ACP) ranked highest for pain relief. Interventions that ranked highest for ROM improvement included open repair, PT, and A+DR with or without ACP. Interventions that ranked highest for PROs included arthroscopic footprint microfracture with or without SR, open repair, and A+SR with or without ACP. CONCLUSIONS: Based on a network meta-analysis of level 1 studies, arthroscopic rotator cuff repair with a SR or DR construct demonstrates similar retear rates, PROs, and clinical outcomes. The highest-ranking treatment for minimizing retears was arthroscopic repair with DR constructs and PRP augmentation, although open repair and arthroscopic SR remain reliable options with excellent clinical outcomes. Addition of PRP to DR constructs trended toward a 56% decreased risk of retear as compared to DR repair alone. Although no single treatment emerged superior, several interventions offered excellent clinical improvements in pain, ROM, and PROs that exceeded minimal clinically important difference thresholds. LEVEL OF EVIDENCE: I, systematic review and meta-analysis of level I studies.

Incidence and risk factors for symptomatic venous thromboembolism following anterior cruciate ligament reconstruction.

PURPOSE: To determine the incidence of symptomatic venous thromboembolism (VTE) following anterior cruciate ligament (ACL) reconstruction using a large national database and to identify corresponding independent risk factors. METHODS: The Humana administrative claims database was reviewed for patients undergoing ACL reconstruction from 2007 to 2017. Patient demographics, medical comorbidities, as well as concurrent procedures were recorded. Postoperative incidence of VTE was measured by identifying symptomatic deep vein thrombosis (DVT) and pulmonary embolism (PE) at 30 days, 90 days, and 1 year postoperatively. Univariate analysis and binary logistic regression were performed to determine independent risk factors for VTE following surgery. RESULTS: A total of 11,977 patients were included in the study. The incidence of VTE was 1.01% (n = 120) and 1.22% (n = 146) at 30 and 90 days, respectively. Analysis of VTE events within the first postoperative year revealed that 69.6% and 84.3% of VTEs occurred within 30 and 90 days of surgery, respectively. Logistic regression identified age ≥ 45 (odds ratio [OR] = 1.88; 95% confidence interval [CI] 1.32-2.68; p < 0.001), inpatient surgery (OR = 2.07; 95% CI 1.01-4.24; p = 0.045), COPD (OR = 1.51; 95% CI 1.02-2.24; p = 0.041), and tobacco use (OR = 1.75; 95% CI 1.17-2.62; p = 0.007), as well as concurrent PCL reconstruction (OR = 3.85; 95% CI 1.71-8.67; p = 0.001), meniscal transplant (OR = 17.68; 95% CI 3.63-85.97; p < 0.001) or osteochondral allograft (OR = 15.73; 95% CI 1.79-138.43; p = 0.013) as independent risk factors for VTE after ACL reconstruction. CONCLUSIONS: The incidence of symptomatic postoperative VTE is low following ACL reconstruction, with the majority of cases occurring within 90 days of surgery. Risk factors include age ≥ 45, inpatient surgery, COPD, tobacco use and concurrent PCL reconstruction, meniscal transplant or osteochondral allograft. LEVEL OF EVIDENCE: III.

Establishing Clinically Significant Outcomes After Anterior Cruciate Ligament Reconstruction in Pediatric Patients.

PURPOSE: The purpose of this study was to establish clinically significant outcome values for the minimal clinically important difference (MCID) and patient acceptable symptomatic state (PASS) after anterior cruciate ligament reconstruction (ACLR) in the pediatric and adolescent populations and to assess factors that were associated with achieving these outcomes. METHODS: Patients between the age of 10 to 21 who underwent ACLR between 2016 and 2018 were identified and patient-reported outcomes (PROs) were collected preoperatively and postoperatively. Intraoperative variables collected included graft choice, graft size (diameter), graft fixation method, and concomitant procedures. PROs collected for analysis were the International Knee Documentation Committee Score (IKDC) and Knee Injury and Osteoarthritis Outcome Score (KOOS). MCID and PASS were calculated using receiver operating characteristic with area under the curve analyses for delta (ie, baseline-to-postoperative change) and absolute postoperative PRO scores, respectively. RESULTS: A total of 59 patients were included in the analysis. Of the entire study population, 53 (89.8%) reported satisfaction with their surgical outcome. The established MCID threshold values based on the study population were 33.3 for IKDC, 28.6 for (KOOS) Symptoms, 19.4 for Pain, 2.9 for activities of daily living (ADL), 45.0 for Sport, and 25.0 for Quality of Life (QoL). Postoperative scores greater than the following values corresponded to the PASS: 80.5 for IKDC, 75.0 (KOOS) Symptoms, 88.9 for Pain, 98.5 for ADL, 75.0 for Sport, and 68.8 for QoL. CONCLUSION: Clinically meaningful outcomes including MCID and PASS were established for pediatric ACLR surgery using selected PRO measures, IKDC, and KOOS. Patient age, sex, graft type, and graft size were not associated with greater achievement of these outcomes. In contrast, collision sports, fixed-object high-impact rotational landing sports, and concomitant meniscectomy surgery were associated with a decreased likelihood of achieving clinically significant improvement. However, findings must be interpreted with caution due to limitations in follow-up and sample size. LEVEL OF EVIDENCE: Level IV: case series.

Intraoperative Computer Vision Integrated Interactive Fluoroscopy Correlates With Successful Femoroplasty on Clinic-Based Radiographs.

PURPOSE: To quantitatively evaluate computer vision interface (CVI)-guided femoroplasty in the arthroscopic treatment of femoroacetabular impingement syndrome and compare those results with traditional unguided resections. METHODS: Consecutive patients undergoing hip arthroscopy for femoroacetabular impingement syndrome between July 2019 and October 2019 were evaluated. Cases with CVI were identified along with controls, consisting of patients from the same study period who underwent surgery without the CVI and were balanced for age, sex, laterality, and preoperative alpha angles. Alpha angles were measured on pre- and postoperative clinic radiographs, as well as intraoperatively for the CVI group. Cam resections were quantified by measuring pre- and postresection alpha angles and compared between groups. The correlation between CVI views and office-based radiographs was assessed, and the 3 CVI views that best correlated with each of the 3 standard clinic radiographs were evaluated for accuracy and performance in detection of cam deformity with alpha angle ≥48° with the clinic-based films as the reference. RESULTS: A total of 49 patients (51 hips) (average age, 28.7; 33 female patients) in the CVI group, and 51 patients (51 hips) (average age: 29.9; 35 female patients) in the control group. There were no significant differences between groups with respect to age, sex, laterality, or preoperative alpha angle (all P > .05). Significant alpha angle reduction occurred on all intraoperative and postoperative clinic views (all P < .01). The CVI views that best correlated with the clinic radiographs were 11:45 with the anteroposterior (ρ = 0.588, P = .0025), 12:30 with the Dunn lateral (ρ = 0.632, P = .0009), and 1:45 with the false-profile (ρ = 0.575, P = .0033). Greater reliability was observed with 12:30/Dunn (accuracy = 83.33%, P < .0001; sensitivity = 77.14%; specificity = 87.76%) and 1:45/false-profile (accuracy = 82.35%, P = .0051; sensitivity = 81.82%; specificity = 82.61%) than with 11:45/anteroposterior (accuracy = 69.15%, P = .0077; sensitivity = 56.10%; specificity = 79.25%). CONCLUSIONS: CVI-guided cam resection results in successful resection of proximal femur cam lesions and represents a femoroplasty templating method that does not require preoperative computed tomography imaging or additional invasive intraoperative referencing modules. The accuracy and adequacy of this resection was validated by comparison with routine clinic radiographs. LEVEL OF EVIDENCE: Therapeutic Level III: retrospective comparative analysis.

Osteochondral Allograft Transplantation of the Knee in Adolescent Patients and the Effect of Physeal Closure.

PURPOSE: The primary aim was to compare osteochondral allograft (OCA) transplantation outcomes between adolescent patients aged 16 years or younger and those older than 16 years. A secondary aim was to analyze the association between physeal closure status and outcomes. METHODS: Consecutive patients aged 18 years or younger who underwent OCA transplantation with a minimum 2-year follow-up were identified from a prospectively collected database. Patients were divided into 2 groups: those aged 16 years or younger (group 1) and those aged 17 to 18 years (group 2). Outcomes included patient-reported outcomes (PROs), complications, reoperations, and cartilage revision surgery. Outcomes were compared between groups, and physeal status was analyzed as a prognostic indicator. RESULTS: A total of 36 patients met the inclusion criteria: 18 in group 1 and 18 in group 2. There were no significant differences between the groups in terms of demographic characteristics, prior surgical procedures, and surgical details, including concomitant procedures. The mean overall follow-up period was 4.6 ± 2.5 years (range, 2-10.3 years), with no significant difference between the groups (P = .21). There were 10 reoperations (28.8%), 4 in group 1 and 6 in group 2 (P = .47). The overall time to reoperation was 2.8 years and did not significantly differ between groups (P = .75). The failure rate was 5.6%, with 1 patient in each group undergoing either graft debridement or revision OCA transplantation. All PROs were significantly improved postoperatively (P < .05), except for the Western Ontario and McMaster Universities Arthritis Index stiffness score (P = .28) and the Short Form 12 mental score (P = .19). There were no significant between-group differences in terms of PROs. Patients with closed physes had a significantly greater increase in most PROs compared with patients with open physes (P < .05). CONCLUSIONS: OCA transplantation in adolescents results in significant PRO score improvement and a low failure rate, albeit reoperations are not uncommon. Patients with closed physes show greater PRO score improvement than those with open physes. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Time to closure of orthopaedic surgical incisions: a novel skin closure device versus conventional sutures.

OBJECTIVE: New technologies are being developed to optimise healing of surgical incisions. BandGrip (US) is a micro-anchor skin closure device that replaces the need for subcuticular suturing and further dressing. The purpose of this study is to perform a matched cohort analysis comparing time to closure of surgical incisions between sutures and the novel skin closure device. METHOD: Patients undergoing orthopaedic surgery in 2019 underwent skin closure with either conventional sutures or the novel skin closure device. Patients were divided into three groups according to their procedural incisions: anterior cruciate ligament reconstruction (ACLR); simple arthroscopy; and general incisions. Patients who underwent closure of their surgical incision with the novel skin closure device were matched with patients undergoing superficial closure with sutures. Statistical analysis was performed to compare time to closure per centimetre of skin incision between the groups. RESULTS: A total of 86 patients were included in the study. Overall mean time to closure using the novel skin closure device was less than with sutures (8.6 seconds/cm versus 42.8 seconds/cm, respectively, p<0.001). Mean time to closure for ACLR incisions was 3.7 seconds/cm using the novel skin closure device and 35.5 seconds/cm using sutures (p<0.001). Mean time to closure for simple arthroscopy portals was 19 seconds/cm using the novel skin closure device and 47.6 seconds/cm using sutures (p<0.001). CONCLUSION: BandGrip is a novel skin closure device that allows for efficient surgical incision closure. Time to surgical skin incision closure is significantly less with the use of the novel skin closure device when compared with conventional sutures.

Hyaluronic acid and platelet-rich plasma for the management of knee osteoarthritis.

PURPOSE: Symptomatic knee osteoarthritis (OA) remains a substantial cause of pain and disability worldwide and effective management in young patients without indications for total knee arthroplasty remains challenging. Intra-articular injections represent a viable option in the non-operative treatment of knee OA. Hyaluronic acid (HA) and platelet-rich plasma (PRP) are two commonly utilized intra-articular treatment modalities that are of particular clinical interest in the current literature. The purpose of this manuscript is to provide a concise review of the current literature on the use of HA, PRP, and HA-PRP conjugates for the treatment of symptomatic knee OA. METHODS: A review of the literature utilizing PubMed, OVID/Medline, and Cochrane databases on basic science and clinical literature pertaining to preparation, composition, and outcomes of HA, PRP, and HA-PRP conjugates in patients with symptomatic knee OA. RESULTS: Both HA and PRP have been shown to be efficacious for the treatment of symptomatic knee OA, with HA injections providing limited short-term improvement, while PRP may provide greater therapeutic relief, particularly with the use of leukocyte-poor (LP-PRP) formulations. Despite limited data, the combination of different formulations of HA-PRP conjugates may provide a synergistic effect, resulting in a clinically significant improvement in both pain and function. CONCLUSION: In patients with symptomatic knee OA, intra-articular HA and PRP provide short-term improvement in pain and function, while the efficacy of HA-PRP conjugates warrants further study.

Architecture of the Short External Rotator Muscles of the Hip.

BACKGROUND: Muscle architecture, or the arrangement of sarcomeres and fibers within muscles, defines functional capacity. There are limited data that provide an understanding of hip short external rotator muscle architecture. The purpose of this study was thus to characterize the architecture of these small hip muscles. METHODS: Eight muscles from 10 independent human cadaver hips were used in this study (n = 80 muscles). Architectural measurements were made on pectineus, piriformis, gemelli, obturators, quadratus femoris, and gluteus minimus. Muscle mass, fiber length, sarcomere length, and pennation angle were used to calculate the normalized muscle fiber length, which defines excursion, and physiological cross-sectional area (PCSA), which defines force-producing capacity. RESULTS: Gluteus minimus had the largest PCSA (8.29 cm2) followed by obturator externus (4.54 cm2), whereas superior gemellus had the smallest PCSA (0.68 cm2). Fiber lengths clustered into long (pectineus - 10.38 cm and gluteus minimus - 10.30 cm), moderate (obturator internus - 8.77 cm and externus - 8.04 cm), or short (inferior gemellus - 5.64 and superior gemellus - 4.85). There were no significant differences among muscles in pennation angle which were all nearly zero. When the gemelli and obturators were considered as a single functional unit, their collective PCSA (10.00 cm2) exceeded that of gluteus minimus as a substantial force-producing group. CONCLUSIONS: The key findings are that these muscles have relatively small individual PCSAs, short fiber lengths, and low pennation angles. The large collective PCSA and short fiber lengths of the gemelli and obturators suggest that they primarily play a stabilizing role rather than a joint rotating role.

Secondary Ossification Center Appearance and Closure in the Pelvis and Proximal Femur.

INTRODUCTION: Variable ossification patterns of the pelvis in skeletally immature patients can make the interpretation of pelvic radiographs challenging. Inconsistencies among prior studies and lack of sex comparisons underscore the need for a more comprehensive characterization of the secondary ossification centers. This study evaluates the chronology and sex differences for appearance and closure of pelvic and proximal femoral secondary ossification centers using computed tomography (CT). METHODS: Patients who underwent abdominal and pelvic CT scans between January 2009 and December 2014 at 2 tertiary level 1 trauma centers were retrospectively reviewed. Patients between the ages of 2 and 32 years with adequate imaging of the pelvis and proximal femurs were included. Patients with a history of orthopaedic trauma or pathology affecting ossification were excluded. CT scans were assessed for the appearance and closure of the following secondary ossification centers: anterior inferior iliac spine (AIIS), anterior superior iliac spine (ASIS), femoral head (FH), greater trochanter (GT), iliac crest (IC), ischial tuberosity (IT), lesser trochanter (LT), posterior superior iliac spine (PSIS), symphysis pubis (SP), and triradiate cartilage (TRC). Basic descriptive statistics are reported. RESULTS: A total of 496 CT scans met inclusion criteria (240 males and 256 females). The order of appearance of the secondary ossification centers was: (male) GT, LT, AIIS, IT, ASIS, PSIS, IC, and SP; (female) GT, LT, IT, AIIS, PSIS, IC, ASIS, and SP. The order of closure was similar: (male) TRC, LT, FH, AIIS, GT, ASIS, PSIS, IT, IC, and SP; (female) LT, TRC, AIIS, FH, GT, ASIS, PSIS, IT, IC, and SP. Female ossification centers appeared ∼1 to 2 years before males in all locations. Female ossification centers closed ∼1 to 2 years before males in all locations except TRC, IC, and SP. CONCLUSIONS: The appearance and closure of the pelvis and proximal femur secondary ossification centers follow a predictable pattern of development, occurring slightly earlier in females than males. Knowledge of more precise ages of development and sex differences better characterize this complex skeletal development. Future studies may use secondary ossification centers to further evaluate skeletal maturity, assess pediatric pathology, and aid surgical management. LEVEL OF EVIDENCE: Level III.

Analysis of Acetabular Ossification From the Triradiate Cartilage and Secondary Centers.

BACKGROUND: Acetabular development is a complex process that involves both endochondral growth from the triradiate cartilage (TRC) and intramembranous growth from the primary and secondary ossification centers of the innominate bones. Ponseti and others have described these centers including their contribution toward the development of normal acetabular shape. Prior studies have not utilized advanced imaging to study the appearance and closure of these secondary centers. The purpose of this study was to determine the chronological age at which the secondary ossification centers of the acetabulum appear and close and where there are any sex differences. METHODS: Patients who underwent abdominal and pelvic computed tomography (CT) scans between January 2009 and December 2014 at a pediatric hospital were retrospectively reviewed. Patients between age 6 and 16 years with adequate imaging of acetabulum were included. CT scans were assessed for the appearance and closure of the 3 acetabular secondary ossification centers [anterior (os pubis), superior (os ilium), and posterior (os ischium)] and closure of the TRC. RESULTS: A total of 159 CT scans met inclusion criteria (66 males and 93 females). The median age of appearance of the secondary ossification centers was: posterior (10.1 females, 12.8 males), anterior (10.7 females, 13.4 males), and superior (11.1 females, 13.6 males). The median age of closure of the secondary ossification centers was: posterior (12.8 females, 13.6 males), anterior (12.8 females, 13.9 males), superior (14.5 females, 13.9 males), and TRC (14.5 females, 14.3 males). Most ossification centers in females appeared and closed approximately 2 to 3 years before males. CONCLUSIONS: Secondary ossification centers in the acetabulum appear sequentially (first posterior, then anterior, then superior), with almost all centers closing just before TRC. Closure occurs earlier in females than males. Knowledge of these centers and their closure patterns allows better radiologic readings (especially CT studies) and understanding of acetabular growth, allowing more informed management of childhood hip conditions including dysplasia, trauma, and over-use sports injuries. LEVEL OF EVIDENCE: Level III-Diagnostic.

Femoroacetabular Impingement Measurements Obtained From Two-Dimensional Radiographs Versus Three-Dimensional-Reconstructed Computed Tomography Images Result in Different Values.

Purpose: To compare the reliability and accuracy of radiographic measurements obtained from 2-dimensional (2D) radiographs and 3-dimensional (3D)-reconstructed computed tomography (CT) images in the assessment of femoroacetabular impingement syndrome (FAIS). Methods: Consecutive patients with FAIS from January 2018 to December 2020 were identified and included in this study. Two fellowship-trained surgeons and 2 fellows performed blinded radiographic measurements. Lateral center-edge angle (LCEA) and Tönnis angles were measured on anteroposterior pelvic radiographs, and alpha angles were measured on frog lateral radiographs. Reliability coefficients for individual measurement accuracy were performed using the Cronbach alpha and intra- and inter-rater intraclass correlation coefficients (ICCs). Composite measurements for LCEA, Tönnis angle, and alpha angle were compared with the corresponding 3D value using paired sample t-tests. Results: Fifty-three patients with FAIS with standardized 2D radiographic and 3D-reconstructed CT imaging were included. All reliability metrics met thresholds for internal reliability. Inter-rater ICCs for LCEA, Tönnis angle, and alpha angle were (0.928, 0.888, 0.857, all P < .001). When we compared 2D radiographic measurements with 3D-reconstructed CT values, there was a significant difference in the LCEA for 2 authors: surgeon 1 (mean [M] = -9.14, standard deviation [SD] = 5.7); t(52) = -11.6, P < .001, and surgeon 2 (M = -5.9°, SD = 4.7); t(52) = -9.2, P < .001. Significant differences were seen for Tönnis angle for 2 authors: fellow 2 (M = 3.9°, SD = 5.6); t(52) = 5.1, P < .001, and surgeon 2 (M = -2.6°, SD = 4.1); t(52) = -4.6, P < .001. Alpha angle measurements compared to the 3D-reconstructed alpha angle at 2 o'clock was significantly different for 3 authors: fellow 1 (M = 11.9°, SD = 16.2); t(52) = 5.3, P < .001; fellow 2 (M = 10.4°, SD = 18.6); t(52) = 4.1, P = .002; and surgeon 2 (M = -6.5°, SD = 16.2); t(52) = -2.9, P = .005. Positive mean values indicate 2D radiographic measurements overestimated 3D reconstruction values and negative mean values indicate underestimation. Conclusions: The use of 2D radiographs alone for preoperative planning of FAIS may lead to inaccuracies in radiographic measurements. Level of Evidence: Level, III retrospective cohort study.

Three-Dimensional Computed Tomography Reconstructions May Detect Pincer Lesions With Higher Sensitivity Than Radiographs in Patients With Femoroacetabular Impingement Syndrome.

Purpose: To assess the diagnostic capability of radiographs (XRs) to detect pincer lesions compared with 3-dimensional (3D) computed tomography scans in patients undergoing hip arthroscopy for femoroacetabular impingement syndrome (FAIS). Methods: We performed a retrospective review of all patients who underwent hip arthroscopy for FAIS between September 1, 2020, and October 2, 2022. Preoperative imaging was reviewed. Pincer lesions were defined as a lateral center-edge angle greater than 40°; a Tönnis angle greater than 0°; the presence of the ischial spine, crossover, or posterior wall sign; and the presence of overcoverage greater than 80%. Under "select criteria," patients were classified as having a pincer lesion on XRs and 3D computed tomography reconstructions (CTRs) based on the lateral center-edge angle or Tönnis angle alone, whereas "all criteria" added the presence of the crossover sign and coverage percentage. Statistical analysis was performed to determine the diagnostic accuracy of XRs compared with 3D CTRs. Results: A total of 69 patients met the inclusion criteria. There were 21 male patients (30.4%) and 48 female patients (69.6%). The mean age was 33 ± 13.5 years. χ2 Analysis for select criteria found that 3D CTR was more likely than XRs to detect a pincer lesion. χ2 Analysis for all criteria found that 3D CTR was more likely than XRs to detect a pincer lesion. χ2 Analysis further showed that when using XRs, a pincer lesion was more likely to be detected under all criteria than under select criteria. Likewise, when using 3D CTR, a pincer lesion was more likely to be detected under all criteria than under select criteria. Conclusions: In this study, we found that 3D CTR detected pincer lesions in patients undergoing hip arthroscopy for FAIS with significantly higher sensitivity than XRs alone. Level of Evidence: Level III, retrospective cohort study.

Posterolateral Corner Reconstruction: Surgical Technique and Postoperative Rehabilitation.

Anatomic posterolateral corner (PLC) reconstruction is utilized for ligamentous knee instability associated with PLC injury in patients who desire a return to active lifestyles1,2. The fibular collateral ligament (FCL) and popliteal tendon (PLT) are reconstructed in anatomic fashion according to techniques described by LaPrade et al.3-7. Description: Various PLC reconstruction techniques have been described; however, the preferred reconstruction technique of the senior author is the method developed by LaPrade et al. that restores the anatomy of the 3 primary stabilizers of the PLC, including the FCL, PLT, and popliteofibular ligament3,5,6. Alternatives: Alternative nonoperative treatments include knee immobilization for 4 weeks and physical therapy. Surgical alternatives include PLC repair, which involves repair of the lateral collateral ligament, PLT, and/or popliteofibular ligament if structures can be anatomically reduced to their attachment site. However, repair of acute grade-III PLC injuries with staged treatment of concurrent cruciate injuries is associated with a substantially higher postoperative PLC failure rate8-10. Rationale: Clinical outcomes have demonstrated that primary repairs have significantly higher rates of reoperation compared with reconstruction; therefore, reconstruction is recommended. Treatment of grade-III PLC injuries with reconstruction of midsubstance tears and any associated cruciate ligament tears results in significantly improved objective stability11. In addition, anatomic PLC reconstruction has demonstrated improved subjective and objective patient outcomes compared with nonsurgical treatment or repair5,11,12. Expected Outcomes: Reconstruction of the PLC offers excellent outcomes after surgery. Studies have shown that the fibular-based technique for treatment of a chronic isolated PLC injury showed good results in terms of clinical outcome, restoring knee varus and rotational stability13. Important Tips: Patients with associated proximal tibiofibular joint instability will benefit from this reconstruction because this technique will add stability to the joint.This surgical approach is technically demanding, requiring proficiency with surgical dissection.Damage to the common peroneal nerve can potentially occur. Careful dissection and placement of retractors should be observed.Risks include surgical failure due to unrecognized malalignment; especially in chronic cases, the patient should have a complete evaluation of the standing alignment and tibial slope12. Acronyms and Abbreviations: FCL = fibular collateral ligamentPFL = popliteofibular ligamentPLC = posterolateral cornerIT = iliotibialIKDC = International Knee Documentation CommitteeACL = anterior cruciate ligamentPCL = posterior cruciate ligamentPEEK = polyetheretherketonePROM = passive range of motion.