Sierra, Rafael J.

Abstract Introduction Periacetabular osteotomy (PAO) is a complex reconstructive procedure performed to address acetabular dysplasia. Postoperative pain management is challenging due to surgical invasiveness and the need to limit opioid use. Regional and local anesthesia are commonly used but may be short-lived, increasing opioid requirements. However, methadone is a long-acting analgesic that may offset these limitations. This is the first study to evaluate methadone use in PAO with arthroscopy, comparing efficacy and opioid consumption of three different anesthetic regimens: (1) lumbar plexus catheter with a single shot intrathecal hydromorphone (LP+HM) (2) locally administered intraoperative soft tissue periarticular injection with ropivacaine, epinephrine, and ketorolac (arthroplasty block [AP]), and (3) AP with intraoperative methadone (AP+M). Methods We retrospectively reviewed PAO with arthroscopy cases from 2022 to 2025 at a single tertiary center. All cases were performed by the same surgeon and anesthesia team and managed on the same postoperative floor. Patients were categorized into three groups: (1) LP+HM, (2) AP, and (3) AP+M. Primary outcomes were 48-hour morphine milligram equivalents (MME) and total inpatient opioid consumption. Length of stay (LoS), operative time, VAS pain scores at 24h and 48h, and antiemetic use were also collected. Results Fifty PAO procedures were identified. The mean age was 16.0±2.3 years, 96% were female, and mean BMI was 22.8±4.4 kg/m2. No significant differences were seen between groups. The addition of methadone to the arthroplasty block regimen (AP+M) resulted in significantly lower 48-h MME compared to AP alone (55.9 mg vs 83.3 mg, p=0.030), but did not differ significantly from LP+HM (39.0mg, p=0.593). Total inpatient opioid consumption was also significantly reduced in the AP+M (69.3 mg) and LP+HM (66.7 mg) groups compared to AP (110.5 mg, p=0.012). Similarly, 24-hour pain scores were significantly lower in the AP+M (3.6±1.9) and LP+HM (3.7±2.1) groups compared to AP (6.4±1.6, p=0.041). Length of stay was comparable across groups (p=0.39). Conclusion Intraoperative methadone added to the arthroplasty block provided comparable analgesia and reduced total opioid use compared to arthroplasty block alone. These findings support methadone as an adjunct to periarticular anesthesia for improving pain control and reducing opioid use in hip preservation surgery.

Abstract Introduction The utilization of total hip arthroplasty (THA) in skeletally immature patients remains controversial, with an open triradiate cartilage traditionally perceived as a relative contraindication due to concerns of acetabular fixation and component loosening. Early evidence suggests that THA may be a feasible option in this patient population yielding favorable short-term outcomes, however larger series and mid-term data are lacking. This study presents the largest series of THA in patients with open triradiate cartilage to date with mid-term clinical, radiographic, and patient-reported outcomes. Methods A retrospective review of our institutional Total Joint Registry identified 19 patients (22 hips) who underwent THA while having an open triradiate cartilage growth plate between the year 2000 and 2024. Skeletal maturity was assessed utilizing the modified Oxford bone age and all patients had a score of “1” or “2” on the triradiate cartilage stage of maturation. Demographics, surgical characteristics, implant data, radiographic parameters, and clinical outcomes were collected. Functional hip scores were assessed via the Harris Hip Score (HHS). Kaplan-Meier analysis was performed to analyze reoperation rates. Results The average age at surgery was 14 years (SD=1.68), the average BMI was 24 (SD=7.1) and 64% were male. Mean follow-up was 6.05 years (range 1-15). The mean modified Oxford bone age for this cohort was 23 (SD=1.4). The most common indications for THA were avascular necrosis (64%), degenerative joint disease (27%), and neoplasia (9%). Preoperatively, 54.5% of patients utilized gait aids. Postoperatively, all patients reported independent ambulation without assistive devices with an average HHS of 91.65 (SD=11.42). Ninety-six percent of implants were stable at final radiographic follow up. Both reported complications involved acetabular cup loosening, requiring revision of the acetabular component. Conclusion This study presents the largest cohort in the literature of patients who underwent THA with open triradiate cartilage. Our results highlight high patient reported outcomes and low revision rates at mid-term follow up. All patients had excellent implant fixation without radiographic signs of loosening at final radiographic follow up. These results support the use of THA in skeletally immature patients without the need to delay THA for closure of the triradiate cartilage.

Abstract Introduction Periacetabular osteotomy (PAO) is performed in the setting of hip dysplasia to increase acetabular coverage of the femoral head and improve joint biomechanics and longevity. PAO fixation is generally achieved with two or three 4.5 mm screws, as compared to the generally more substantial plate and screw constructs used in the setting of acetabular fractures or pelvic ring injuries. The purpose of this study was to evaluate postoperative changes in hip joint center medialization and lateral acetabular coverage following PAO, understanding that these radiographic measures are generally used to guide intra-operative assessment of correction. Methods A retrospective chart review of 100 consecutive PAOs during 2021-2023 at a single academic institution by four surgeons was performed. Perioperative radiographs and fluoroscopy images were evaluated to measure lateral center edge angle (LCEA), Tönnis angle, and medialization of the hip joint center. The hip joint center was measured at one-third of the diameter of the femoral head from inferior to superior, to the ilioischial line, as previously validated by Fowler and colleagues. Results One hundred PAOs in 87 patients (87% female, mean age: 23.0 years) were included. Average preoperative radiographic parameters were 19.9° for LCEA, 12.5° for Tönnis angle, and 12.6 mm for distance from the femoral head to ilioischial line. Ninety-four cases (94%) used three screws, and 6 cases (6%) used two screws for unstable fragment fixation. On immediate postoperative films, average correction was to 28.3° for LCEA, 4.9° for Tönnis angle, and 1.9 mm of pre- to postoperative femoral head medialization (p≤0.001). Patients were radiographically followed for an average of 13.3 months, with an average time to radiographic union of 7.1 months. During the course of follow-up, LCEA increased to 29.3°, Tönnis angle remained to 5.0° (p=0.47), and medialization increased to 2.7 mm (p≤0.02), suggesting further significant but clinically modest increases in lateral coverage and femoral head medialization. Conclusion While the majority of lateral acetabular coverage and femoral head medialization occurs intra-operatively at the time of PAO, patients undergo modest but statistically significant postoperative increases in lateral coverage and medialization prior to radiographic union.

Abstract Introduction Understanding factors that impact outcomes of total hip arthroplasty (THA) can aid clinical decision-making and patient counselling. The purpose of this study was to investigate functional outcomes, complications, and reoperation rates among patients undergoing primary THA after hip arthroscopy (HA-THA) compared to a matched cohort of primary THA patients without prior arthroscopy (THA-only). Methods A retrospective review was performed to identify all patients who underwent primary THA after prior hip arthroscopy from 2009-2022 at a single institution. Patients with a history of revision arthroscopy were excluded. Cases were propensity-matched with primary THA controls in a 1:4 ratio by age at time of THA, sex, body mass index, surgical approach, and year of surgery. At minimum 2-year follow-up, patient-reported outcomes (PROs) including Forgotten Joint Score (FJS), Modified Harris Hip Score (mHHS), Hip Disability and Osteoarthritis Outcome Score Pain (HOOS pain), and Visual Analog Pain Scale (VAS) were analyzed. Results Sixty-three hips in 60 patients (age: 47.3±9.4 years, BMI: 29.8±6.2 kg/m2) were matched to 252 THA-only hips, with patients converting to THA at a mean 3.1 years (range 0.3-10.3) following hip arthroscopy. While both HA-THA and THA patients demonstrated significant (p<0.001) postoperative improvements in PROs, HA-THA patients reported significantly lower postoperative FJS, mHHS, HOOS pain, and VAS pain scores (p<0.001) as compared to THA-only controls. At mean 6.6±3.2 years follow-up, HA-THA patients with preoperative Tönnis grades 2-3 reported significantly increased FJS, mHHS, and HOOS pain compared to those with preoperative Tönnis grades of 0-1 (p≤0.03). Additionally, HA-THA patients with preoperative Tönnis grades 0-1 exhibited worse PROs (p<0.001) as compared to THA-only controls. While there were no differences in complication rates between HA-THA patients and THA-only controls (8% vs. 5%, p=0.49), all-cause reoperation was greater amongst HA-THA patients compared to THA-only (10% vs. 2%, p=0.01). Conclusion While improved compared to preoperatively, patients undergoing THA after prior hip arthroscopy demonstrated inferior outcomes at mid-term follow up as compared to a demographically age-matched cohort without prior arthroscopy. When considering conversion to THA following arthroscopy, clinicians should consider counseling patients regarding improved outcomes in the setting of advanced radiographic osteoarthritis, and potentially increased all-cause reoperation.

Abstract Osteonecrosis (ON) of the femoral head is a significant complication following chronic corticosteroid treatment, especially in adolescents and young adults. While studies in the adult population suggest that early core decompression augmented with bone marrow aspirate concentrate injection (BMAC) may reduce progression, evidence in younger patients remains scarce. This study evaluates survivorship free from femoral head collapse and conversion to total hip arthroplasty following core decompression with BMAC in patients under 25 years old with corticosteroid-induced femoral head ON. A retrospective review was conducted of 13 patients (24 hips) who underwent hip core decompression with BMAC for corticosteroid-induced femoral head ON. Variables analyzed included sex, body-mass index, age at index surgery, continued corticosteroid use, concomitant labral tear, Kerboul angle/grade, and Steinberg classification of osteonecrosis. These variables were assessed for their association with survivorship free of THA, conversion to THA, and patient reported outcomes (PROs) (modified Harris Hip Score [mHHS] and Hip Disability and Osteoarthritis Outcome Score [HOOS-12]). The mean follow-up duration was 10 ± 5.4 years. At the final follow-up, 11 hips (45.8%) required reoperation, including 10 total hip arthroplasties and one femoral head resurfacing. Progression to radiographic femoral head collapse occurred in 9 hips (37.5%), resulting in a collapse-free survival rate of 62.5%. The mean survival time until reoperation was 8.34 years. Continued corticosteroid use (p=0.033), Steinberg stage >2 (p=0.044), male sex (p=0.045), and high BMI (p=0.002) were associated with increased risk for reoperation. On multivariate analysis, ongoing corticosteroid use (OR=6.4, p=0.01) and Steinberg stage >2 (OR=4.3, p=0.04) were predictors of reoperation. Patient-reported outcomes at final follow-up included a mean mHHS of 77.5 and a HOOS-12 score of 80%. Core decompression with BMAC for corticosteroid induced femoral head ON in adolescents and young adults resulted in collapse-free survival rate of 62.5% at average 10 years follow up with an average reoperation-free survival of 8.34 years. Patients with Steinberg stage ≥2 and ongoing corticosteroid use had high rates of reoperation and conversion to total hip arthroplasty. Our data highlights that careful patient selection and shared decision-making remain critical in optimizing patient outcomes in this challenging patient population.

Abstract Introduction Periacetabular osteotomy (PAO) is a well-established procedure for hip preservation, traditionally performed on conventional radiolucent tables that provide rigid support to the lower extremity. The Pivot Guardian™ Distraction System extension was recently introduced to facilitate concomitant hip arthroscopy and PAO, enhancing surgical efficiency. However, flexible leg support may alter the biomechanical stability of the pelvis during osteotomy cuts, particularly the ischial osteotomy. This study compared intraoperative and perioperative outcomes of PAOs performed with the Guardian Table extension to those performed on conventional radiolucent tables. Methods All PAOs performed by one surgeon since the introduction of the guardian extension were reviewed. Seventy-two PAO cases were identified; 26 were performed on a Guardian table concomitantly with arthroscopic procedures, while 46 were performed on a conventional radiolucent Demographic variables, surgical characteristics, intraoperative complications and perioperative outcomes were compared between the groups. Groups were comparable in age, BMI, smoking status, history of previous hip arthroscopy, and primary diagnoses. Results The use of the Guardian extension had a higher proportion of women (96.2% vs. 73.9%, p=0.018) and longer operative times due to the addition of the hip arthroscopy (170 ± 54 vs. 90 ± 18 min, p < 0.0001). Notably, intraoperative posterior column fractures only occurred with the use of the Guardian table (15.4% vs. 0%, p=0.0062). No other identifiable risk factors contributed to this finding. Fractures were diagnosed based on intraoperative fluoroscopic images, or immediate postop X-rays, or X-rays at the first follow up. Rates of other complications were similar between the two groups. Conclusion While the Guardian Table extension facilitates simultaneous arthroscopic procedures in the context of PAO procedures, its use was associated with an increased risk of intraoperative posterior column fractures. This may be due to the flexible structure of the leg extension component. Surgeons should be aware of the flexible nature of the table and plan for intraoperative stabilization of the distal portion to increase rigidity.

Aims Data on revision of unicompartmental knee arthroplasty (UKA) to total knee arthroplasty (TKA) are limited by low patient numbers and short-term follow-up. This study evaluated the mid-term outcomes of revision of UKA to TKA focusing on implant survival, radiological results, and clinical outcomes in a large series. Methods We identified 235 revisions of UKA to TKA performed between 1995 and 2022 utilizing our institutional total joint registry. The mean age was 65 years (SD 10), mean BMI was 32 kg/m 2 (SD 6), and 50% were female (n = 118). The most common indications for revision were aseptic loosening (37%; n = 83), progression of arthritis in adjacent compartments (35%; n = 81), and unexplained pain (20%; n = 47). The mean time from UKA to revision to a TKA was four years (26 days to 15 years). Posterior-stabilized constructs were used in 78% of the revisions (n = 184), varus-valgus constrained implants in 14% (n = 33), and cruciate-retaining implants in 7% (n = 16). Metaphyseal fixation devices were used in 8% of cases (n = 18) and augments in 31% (n = 73). Kaplan-Meier implant survival analyses were performed, radiographs reviewed, and clinical outcomes were measured with Knee Society Scores (KSSs). Mean follow-up was eight years (2 to 25). Results The five-year survival free of any re-revision was 93% (95% CI 89 to 97). There were 17 further re-revisions with femoral and/or tibial aseptic loosening (n = 7), periprosthetic joint infection (n = 4), and stiffness (n = 2) being the most common indications. The five-year survival free of any reoperation was 87% (95% CI 83 to 92). Stiffness (n = 7) and unresurfaced patellar clunk/crepitus (n = 4) were the most common indications for reoperations without implant exchange. There were 25 nonoperative postoperative complications, most commonly stiffness (n = 5), flexion instability (n = 4), and haematoma (n = 4). No unrevised TKAs showed signs of radiological loosening. KSS function score improved from 54 (SD 18) to 69 (SD 26; p = 0.003). Conclusion In this large series of 235 revisions of UKA to TKA, the five-year survival of the TKAs free of re-revision was good. Our data suggest that the implant survival and clinical outcomes were inferior to primary TKA. Tibial component aseptic loosening was the most common reason for re-revision. Cite this article: Bone Joint J 2025;107-B(12):1281–1287.

Background: Hip decompression effectively treats early-stage osteonecrosis of the femoral head (ONFH) by slowing disease progression and potentially delaying joint replacement. Biological adjuvants like bone marrow aspirate concentrate (BMAC) and platelet-rich plasma (PRP) support bone regeneration and improve outcomes 1–7 . The present video article demonstrates a simple, coreless hip decompression technique with BMAC and PRP injection for early-stage ONFH. Description: The procedure is performed in the same operating room setting as traditional core decompression, with the patient supine on a radiolucent table for fluoroscopic guidance. One or both legs are draped free for access to the iliac crests. Bone marrow is harvested percutaneously from the anterior superior iliac crest with a trocar needle kit, centrifuged, and prepared for injection. We recommend precoating needles and syringes with 1:1,000 heparin to prevent clotting. The BioCUE System (Zimmer Biomet) is typically utilized for centrifugation. Hip decompression is performed with use of a trocar and cannula (PerFuse System; Zimmer Biomet), with subsequent injection through the cannula into the femoral head. A 0.5-cm skin incision is made. The trocar is placed lateral to the femur and advanced percutaneously through the lateral femoral cortex, with a starting point proximal to the lesser trochanter. The trocar is then advanced along the femoral neck into the necrotic region by performing mallet strikes on the instrument’s strike cap. Anteroposterior and frog-leg lateral views assist in positioning the trocar within the necrotic area. Internal leg rotation, which aligns the patella upward, helps position the trocar horizontally parallel to the floor. Positioning is adjusted using repeated imaging as needed. Once the patient is positioned, the trocar is removed, leaving the cannula in place. With the cannula retracted 1 cm, a 30-mL syringe is utilized to inject BMAC and PRP into the necrotic lesion. Because of sclerotic resistance, substantial pressure is needed, but retraction of the cannula helps. Following injection, the cannula is withdrawn another 1 cm, and demineralized bone matrix is injected to prevent escape of the BMAC. Alternatives: Alternative treatments for ONFH include traditional core decompression with a sliding hip screw drill or an X-REAM device (Stryker), both of which carry a higher risk of fracture because of the larger diameter of the tract and require limited weightbearing postoperatively. Bone-cement injection can stabilize the femoral head but lacks regenerative properties. Core decompression with either BMAC or PRP alone, rather than in combination, also serves as an alternative treatment strategy. Open approaches, like osteotomy, are more invasive, have longer recovery times, and may complicate future hip arthroplasty if unsuccessful. Rationale: This technique enables minimally invasive hip decompression and delivery of adjuvant cell therapy or grafting, typically without the use of power instruments. This approach avoids the risk of injuring the bone due to the heat from power tools, protecting the BMAC injection site. Patients are generally discharged the same day and permitted full weight-bearing immediately, even in bilateral surgeries. Expected Outcomes: Hip decompression for ONFH has shown variable rates of success 8,9 , but adding BMAC or PRP may improve outcomes 1–3 . Houdek et al. reported that among 35 hips treated with decompression plus BMAC and PRP for corticosteroid-induced ONFH, 88% avoided THA at 3 years 2 and 70%, at 7 years 3 . Patients with grade-1 or 2 Kerboul angles had a 90% survivorship rate, underscoring the benefits of BMAC and PRP. Important Tips: Insert the trocar into the lateral cortex, positioned distal to the vastus ridge and proximal to the lesser trochanter, to reduce iatrogenic subtrochanteric fracture risk. Avoid advancing closer than 5 mm to the subchondral cortex to prevent joint-surface disruption or collapse, especially with eccentric lesions. If resistance occurs during injection, retract the cannula a few millimeters laterally to increase delivery space and reduce pressure. Acronyms and Abbreviations: BMAC = bone marrow aspirate concentrate ONFH = osteonecrosis of the femoral head PRP = platelet-rich plasma AP = anteroposterior THA = total hip arthroplasty ARCO = Association Research Circulation Osseous classification MRI = magnetic resonance imaging

ABSTRACT Femoroacetabular impingement (FAI) of the hip results from altered morphology of the proximal femur and/or acetabulum, creating abnormal contact between these structures during normal hip range of motion. The etiology of this structural phenotype is unknown. This study aimed to identify common single‐nucleotide variants (SNVs) among two families with seemingly heritable FAI. Additionally, this study examined biologic networks among proteins encoded by identified SNVs and surveyed the literature regarding the role of these proteins in musculoskeletal development. Methodologically, blood samples were collected from affected and unaffected members of two separate families with a pattern of heritable FAI. Exome sequencing identified SNVs, and a protein–protein interaction network assessment, in addition to a literature review, was performed to better understand the role of variant‐associated genes in musculoskeletal development. Results showed 33 and 43 variant‐associated genes affected in Family 1 and Family 2, respectively. Although no overlap in variant‐associated genes was found between families, network analysis showed that variant‐associated genes are functionally interconnected and are known to interact with each other. Furthermore, the variant‐associated genes are broadly associated with musculoskeletal development. Ultimately, genetic analysis of two families of multiple generations of FAI revealed variations in genes regulating musculoskeletal development, with several being critical local regulators of bone morphogenesis.

Abstract The Guardian table is widely utilized for combined hip arthroscopy and periacetabular osteotomy (PAO) due to its postless traction design and the ability to perform both procedures without the need for redraping. This retrospective cohort study reports one surgeon’s use of the Guardian table extension during combined hip arthroscopy and PAO and the occurrence of intraoperative posterior column fractures. Seventy-two consecutive PAO procedures performed at a single institution between February 2023 and January 2025 were analysed. Procedures involving concomitant hip arthroscopy (n = 26) utilized the Guardian table, whereas those without arthroscopy (n = 46) used a conventional radiolucent table. Patient demographics, clinical data, and complications were reviewed. Additionally, mechanical testing quantified table stability by measuring peak absolute acceleration (‘table bounce’) using accelerometry during simulated malleting. The incidence of intraoperative posterior column fractures was significantly higher with the Guardian table (4/26, 15.4%) compared to the conventional table (0/46, 0%; P = .0062). Mechanical testing demonstrated significantly greater table bounce for the Guardian table (69.1 ± 3.4 m/s2 versus 28.2 ± 4.4 m/s2, P < .001). Patient characteristics and surgical complexity did not differ significantly between fracture and non-fracture cases. These findings suggested that the Guardian table extension system was associated with increased risk of posterior column fractures, likely due to lack of distal support and stability. Surgeons should consider alternative table setups or intraoperative support modifications to mitigate this risk during PAO procedures.