Physeal Migration During Knee-guided Growth With Tension Band Plates: Influence of Implant Position.

OBJECTIVE: Physeal migration during guided growth with tension band plates (TBPs) has been poorly described. The positioning factors associated with this phenomenon and its clinical implications are unknown. Our aim is to determine the influence of implant position on the risk of physeal migration during knee-guided growth with TBP. METHODS: Retrospective study of 491 patients who underwent temporary hemi or epiphysiodesis with TBP around the knee between 2007 and 2019. We identified 29 patients who presented physeal migration during follow-up. Demographic and clinical data were collected, and the following measures were obtained from the immediate postoperative radiographs: epiphyseal screw base-physis distance/epiphyseal screw tip-physis distance, interscrew angle, epiphyseal screw-physis angle(ES-PHa)/metaphyseal screw-physis angle, plate-physis angle, epiphyseal screw-plate angle/metaphyseal screw-plate angle, and epiphyseal screw-physis length ratio. Using follow-up radiographs, the type of physeal migration of the epiphyseal screw (touch, occupy, or traverse) and the status of the physis after implant removal (unaltered, physeal bar, and skeletal maturity) were also recorded. A descriptive analysis of the cases and a case-control comparison of imaging studies were performed. RESULTS: The median patient age at intervention was 12.2 years (interquartile range: 11.3 to 14.1), and 76% were males. A statistically significant difference between cases and controls was obtained for epiphyseal screw base-physis distance (3.7 vs 6.3; P = 0.029), epiphyseal screw tip-physis distance (3.6 vs 7.85; P = 0.002), ES-PHa (-0.1 vs 7.45; P = 0.007), and plate-physis angle (85.45 vs 88.60; P = 0.012). In a categorical analysis, a significant difference was found for the ES-PHa categories ( P = 0.002) and for the ES-PHa/metaphyseal screw-physis angle categorical pair ( P = 0.018). In 16, 17, and 12 cases the physis was touched, occupied, or traversed, respectively, although we found no physeal alterations after plate removal. CONCLUSIONS: In our study, physeal migration of TBP is not an uncommon phenomenon, although no physeal abnormalities were detected. Convergent placement of the epiphyseal screw with the base or tip close to the physis should be avoided as this position is associated with a higher risk of physeal migration. LEVEL OF EVIDENCE: Level III-case-control study.

The effectiveness of physeal bar resection with or without Hemi-Epiphysiodesis to treat partial growth arrest.

PURPOSE: To evaluate the outcomes of distal femoral, proximal tibial, and distal tibial physeal bar resection combined with or without the Hemi-Epiphysiodesis procedure and provide a better understanding of the application of physeal bar resection combined with Hemi-Epiphysiodesis procedure in the treatment of physeal bar growth arrest. METHODS: We retrospectively reviewed the patients who suffered physeal bar and underwent physeal bar resection with or without the Hemi-Epiphysiodesis technique during 2010-2020. All were followed up for at least 2 years or to maturity. A modified mapping method was used to determine the area of a physeal bar by CT data. The aLDFA, aMPTA, aLDTA, MAD, and LLD were measured to assess the deformity of the lower limb. RESULTS: In total, 19 patients were included in this study. The average age was 8.9 years (range 4.4 to 13.3 years old). During the follow-up, 4 (21.1%) patients had an angular change < 5°; 12 (63.2%) patients had angular deformity improvement > 5° averaging 10.0° (range 5.3° to 23.2°), and 3 (15.8%) patients had improvement of the angular deformity averaging 16.8° (range 7.4° to 27.1°). Eleven patients (57.9%) had significant MAD improvement. After surgery, we found that 7 (36.8%) patients had an LLD change of < 5 mm and were considered unchanged. Only 2 (15%) patients had an LLD improvement > 5 mm averaging 1.0 cm (range 0.7 to 1.3 cm), and 7 (36.8%) patients had increasing of LLD > 5 mm averaging 1.3 cm (range 0.5 to 2.5 cm). There were no postoperative fractures, infections, or intraoperative complications such as neurovascular injury. CONCLUSION: Physeal bar resection combined with Hemi-epiphysiodesis is helpful for partial epiphysis growth arrest. Without statistically verifying, we still believe that patients with limited growth ability could benefit more from physeal bar resection combined with Hemi-epiphysiodesis.

A More Conservative Approach in the Surgical Management of Pediatric Physeal Ankle Fractures Should be Preferred: Mid to Long-term Functional Outcomes of Three Different Surgical Techniques for Salter-Harris Type II and Triplane Distal Tibial Fractures.

BACKGROUND: Pediatric physeal ankle fractures carry a high risk of complications. This study aimed to (1) investigate the effect of anatomic reduction of the physis on mid to long-term functional outcomes in Salter-Harris type II and triplane distal tibial physeal fractures (DTPFs) and (2) compare the outcomes of 3 different surgical techniques applied in these fractures. METHODS: The database of a single level-I trauma center was retrospectively reviewed for DTPFs between 2012 and 2022. A total of 39 eligible patients with operative Salter-Harris type II and triplane fractures between 2012 and 2022 were included. Surgical treatment methods were closed reduction-percutaneous fixation (CR-PF), open reduction-screw fixation, or open reduction-plate fixation. Patients were further divided into subgroups for fractures reduced anatomically (<1 mm) or nonanatomically (1 to 3 mm). The primary outcome measures were the American Orthopaedic Foot and Ankle Society Score, ankle range of motion, presence of premature physeal closure and angular deformities, and Takakura ankle osteoarthritis grade. RESULTS: A total of 39 patients were included, with an average age of 12.9 ± 2.2 years. The mean follow-up time was 68.9±38.0 months. The CR-PF group had higher postoperative fracture displacement ( P = 0.011). American Orthopaedic Foot and Ankle Society scores were excellent in all groups, statistically similar between surgical techniques, and similar between anatomic and nonanatomic reduction groups. The CR-PF group ( P =0.030) and nonanatomic reduction ( P = 0.030) provided a significantly lower ankle osteoarthritis rate. All 4 patients with premature physeal closure were observed in patients treated with open techniques. CONCLUSIONS: CR-PF for the treatment of DTPFs should be preferred in suitable cases as it is less invasive and provides satisfactory mid to long-term functional outcomes without increasing complications compared with anatomic reduction and open techniques. LEVEL OF EVIDENCE: Level III.

Double vascularized fibula growth plate transfer for the reconstruction of long segmental tibia in pediatric patients: Report of three cases.

Osteosarcoma is a common bone tumor for pediatric patients that has a complex treatment including chemotherapy and radical surgical resection. There are few functional leg reconstruction possibilities described in the literature for pediatric patients due to limited growth potential. The aim of this report is to show long-term results using double vascularized growth plate flaps for the long segmental tibial reconstruction in growing children with satisfactory functionality and preserved limb growth without the use of permanent foreign materials. Three patients with sarcoma in the proximal part of the tibial bone were treated with complex therapy that included preoperative chemotherapy, radical resection of proximal metaepiphysis with tibial growth plate and half of the diaphysis and transplantation of double fibula growth plate flaps-the pedicled ipsilateral and the contralateral as a microvascular flap. The first patient, a male, 13 year with periosteal sarcoma, underwent 17 cm tibial resection with transplantation of the ipsilateral fibula 20 cm and contralateral fibula 20.1 cm, and continued follow-up for 6 years. The second patient, a male, 6 years of age with osteosarcoma, had 14 cm tibial resection with 16 cm ipsilateral and 16.1 cm contralateral fibular transplantation, continued follow-up for 5 years. The third patient, a female, 12 years of age with osteosarcoma, underwent 14 cm tibial resection with 15.4 cm ipsilateral and 15.9 cm contralateral fibular transplantation, and current follow-up of 1 year. Double fibular growth plate transfer is limb-sparing method for a proximal tibial reconstruction with natural growth potential for the pediatric patients.

Temporary hemiepiphysiodesis using eight-plates for angular deformities of the lower extremities in children with X-linked hypophosphataemic rickets.

PURPOSES: Temporary hemiepiphysiodesis (TH) using eight-plates is one of the most frequently performed surgeries for correcting angular deformities of the lower extremities in adolescents. Rarely have studies examined children with X-linked hypophosphataemic rickets (X-LHPR) treated with TH using eight-plates. This study was conducted to investigate the efficacy, the endpoint, and the complications of TH using eight-plates to correct angular deformities of the lower extremities in skeletally immature children. METHODS: We reviewed a total of 26 children (86 physes, 52 knees) with X-LHPR (mean age of 6.2 years, range from 2 to 13 years) who underwent TH using eight-plate to correct angular deformities of the lower extremities. Radiographs and clinical records of these patients were evaluated for demographic data and related clinical factors. RESULTS: The average correction of the mechanical lateral distal femoral angle (mLDFA) was 11.7 ± 8.7° (range from 1.0 to 29.7°), and the average correction of the mechanical medial proximal tibial angle (mMPTA) was 8.4 ± 5.0° (range from 0.3 to 16.7°). The mean deformity correction time was 22.7 months (range from 7 to 60 months), and the mean follow-up after eight-plate removal was 43.9 months (range from 24 to 101 months). Overall, 76.9% (20/26 patients) of the angular deformities of the knee were completely corrected and 15.4% (4/26) of the patients received osteotomy surgery. The femoral correction velocity (0.9° per month) was significantly higher than the proximal tibial (0.6° per month) (p = 0.02). The correction velocity of the mLDFA and mMPTA with the TH procedure was faster than that in the absence of intervention (0.9° vs. 0.2°, 0.7° vs. 0.4° per month, p < 0.05). The correction velocity of the mLDFA (1.2° vs. 0.5° per month, [Formula: see text]) and mMPTA (0.7° vs. 0.5° per month, p = 0.04) of patients whose age ≤ five years old was faster than that of patients whose age > five years old. A total of 69.2% (18/26) patients experienced one TH procedure using eight-plates only. Two patients had screw loosening (2/26, 7.7%). One patient (1/26, 3.8%) had a rebound phenomenon after the removal of eight-plate and had the TH procedure again. There was no breakage, infection, physis preclosure, or limited range of movement found in the follow-up. CONCLUSION: TH using eight-plates is a safe and effective procedure with a relatively low incidence of complication and rebound, and it could be used as part of a streamlined treatment for younger X-LHPR patients with resistant or progressive lower limb deformity despite optimal medical treatment. Early intervention can achieve better results.

Limb Reconstruction After Premature Growth Arrest Secondary to Bone Infections.

During recent years, the detection of osteoarticular infections has increased, thanks to improvement and wide availability of diagnostic tools. Despite that, surgeons and patients still have to deal with long-term sequelae, including osteoarthritis, chronic osteomyelitis, and premature physeal arrest. Subsequent joint reconstruction is the most difficult challenge when the hip or knee has been affected. Most surgical procedures described to manage these devastating consequences are only palliative, with the goal focused on improving stability and pain control, but seldom ending with a highly functional joint. Premature physeal arrest has an unpredictable course after an osteoarticular infection. The prognosis depends on the age of the child, the type of injury (partial or total bony bar), the proportion of the physeal surface affected, and the bone compromised. Peripheral injuries lead to angular limb deformities, whereas central bars lead to limb-length discrepancies. Surgical treatment should be oriented to preserve physeal function and allow normal growth to resume. In those cases where preserving physeal function is not possible, the orthopaedic surgeon must deal with the sequelae of limb-length discrepancies and/or bone deformities.

The Influence of Retrograde Femoral Nail Removal With and Without Interpositional Fat Grafting on Distal Femoral Physeal Behavior: A Sheep Study.

BACKGROUND: Previous investigations have demonstrated that up to 7% of the distal femoral physis can be violated using a rigid, retrograde nail without growth inhibition or arrest. The purpose of this investigation was to evaluate the behavior of the distal femoral physis after retrograde femoral nail removal in a sheep model, with and without placement of an interpositional fat graft. METHODS: Retrograde femoral nails were placed in 8 skeletally immature sheep. Implants were removed at 8 weeks, with the residual defects left open (n=4) or filled with autologous fat graft (n=4). Differences in femoral length between surgical versus contralateral control femurs were measured after an additional 3 (n=4) or 5 months (n=4) before sacrifice, and the physis was evaluated histologically. RESULTS: When compared with control limbs, femoral length was significantly shorter in limbs sacrificed at 3 months (mean: 3.9±1.3 mm; range: 2.7 to 5.7 mm) compared with limbs at 5 months (mean: 1.0±0.4 mm; range: 0.4 to 1.2 mm) ( P =0.005). No significant difference in mean shortening was appreciated in limbs without (2.4±1.6 mm) versus with fat grafting (2.5±2.3 mm) ( P =0.94). Histologic analysis revealed no osteoid formation across the physis in sheep sacrificed at 3 months, whereas there was evidence of early osteoid formation across the physis in sheep at 5 months. All specimens demonstrated evidence of an active physes. CONCLUSIONS: Femurs undergoing retrograde implant placement were significantly shorter when compared with control limbs in sheep sacrificed at 3 months, whereas differences were nominal in sheep sacrificed at 5 months after retrograde implant removal, suggesting growth inhibition with nail removal improved with time. Fat grafting across the distal femoral physis did not result in a significant difference in femoral lengths. Histologic evidence at 5 months revealed early development of a bone bridge, emphasizing the importance of follow-up to skeletal maturity in patients treated with retrograde nailing across an open physis. LEVEL OF EVIDENCE: Level IV.

Factors Affecting Slip Progression After In Situ Screw Fixation of Stable Slipped Capital Femoral Epiphysis.

BACKGROUND: Slip progression after in situ fixation of slipped capital femoral epiphysis (SCFE) has been reported as occurring in up to 20% of patients. We review SCFE treated with in situ single screw fixation performed at 2 hospitals over a 15-year period to determine the factors associated with slip progression. METHODS: This case-control study reviews SCFE treated with in situ single cannulated screw fixation with minimum follow up of 1 year and full closure of the affected physis. Slip progression (failure) was defined as worsening of the Southwick slip angle of 10 or more degrees or revision surgery for symptomatic slip progression. Univariate and multivariate analyses were performed comparing success and failure groups for patient characteristics, screw type and position, and radiographic measurements. RESULTS: Ninety three patients with 108 slips met all criteria, with 15 hips (14%) classified as having slip progression (failure). All failures had 3 threads or fewer across the physis. Five hips had 2 threads across the physis, and 4 of the 5 were classified as failures. Lower modified Oxford bone scores were found in the failure group, though the difference was small (0.9, P=0.013). Failure was also associated with partially threaded screws (P=0.001). Failed hips were associated with lower initial Southwick angles (32.8 degrees) than successful hips (40.4 degrees) (P=0.047). In the stepwise model for multivariate regression, 4 factors were identified as significant, with lower initial number of threads (P<0.0001), mild initial Southwick category (P=0.0050), male sex (P=0.0061), and partially threaded screw type (P=0.0116) predicting failure. CONCLUSION: This study is the largest to date evaluating risk factors for slip progression after SCFE fixation, and the first to consider revision surgery for symptomatic slip progression. For stable SCFE, we demonstrate that 4 threads across the physis with a fully threaded screw of 6.5 mm diameter or greater was sufficient to avoid slip progression. We provide a risk stratification for progression of slip showing that in some cases 3 threads across the physis may be sufficient. LEVEL OF EVIDENCE: Level III-case-control study.

An Anatomic Study of the Proximal Tibial Epiphysis With Relevance to Percutaneous Epiphysiodesis Using Transphyseal Screws (PETS).

BACKGROUND: Percutaneous epiphysiodesis using transphyseal screws (PETS) is a common procedure to correct lower extremity limb-length discrepancies in the pediatric population. A potential complication of this procedure is development of tibial valgus deformity, which may occur secondary to decreased screw purchase in the thinner medial proximal tibial epiphysis. The thickness of the proximal tibial epiphysis has not yet been well quantified, which was the aim of this study. METHODS: Three-dimensional surface scans of 32 cadaveric proximal tibial epiphyses in specimens aged 3 to 17 years old were obtained and computer modeling software was utilized to measure the thickness of the proximal tibial epiphysis at 20 standardized potential screw insertion points according to a generated 5×4 map. RESULTS: When normalized to the total width of the proximal tibial epiphysis, the lateral side is thicker compared with the medial side. The positions with the greatest thickness are located at the midline in the sagittal plane and 33% of the total physeal width away from the medial and lateral edges in the coronal plane (0.265 and 0.261 normalized thickness, respectively). The proximal tibial epiphysis is particularly thin 25% from the medial edge (normalized thickness range: 0.196 to 0.221). Multiple regression analysis revealed a significant relationship between increasing age and female sex with thinner normalized medial and lateral heights. CONCLUSIONS: During PETS, areas for greater screw purchase are located centrally in the sagittal plane and 33% of the total width away from the medial and lateral edges of the proximal tibial epiphysis in the coronal plane. Caution should be taken when inserting screws in the medial 25% of the proximal tibial epiphysis as it is thinner relative to the lateral edge, particularly in females. CLINICAL RELEVANCE: This study provides quantitative, anatomic data on the thickness of the proximal tibial epiphysis, which can direct screw placement during PETS for correcting limb-length discrepancies. These data may help lessen the risk of developing tibial valgus deformity although future clinical studies are necessary to fully evaluate this possibility.

Intercalary reconstruction of the distal femur with or without physeal preservation: results and impact on limb growth.

PURPOSE: Allograft reconstruction with or without vascularized fibula can be a valuable solution to treat childhood intercalary tumours of the distal femur. We aimed to assess the oncological status, complication rate and survival of distal femur intercalary reconstruction after trans-metaphyseal (TMR) and trans-epiphyseal resection (TER). We also evaluated the impact of distal temporary graft fixation on skeletal growth after TMR. METHODS: We retrospectively reviewed 23 skeletally immature patients affected by distal femur osteosarcoma (18) and Ewing sarcoma (5). Mean patients age was 10.3 years. In 11 cases, TMR was performed with physis preservation and temporary distal graft fixation. In 9 patients, TER was performed with growth plate sacrifice. The last 3 cases were treated with TMR and sliding plate fixation. RESULTS: Mean follow-up was 8.4 years. No deaths occurred, but 3 patients presented lung metastasis and 2 cases presented local recurrence in soft tissues. 10 implant-related complications occurred, all surgically treated. At skeletal maturity, mean femoral dysmetria was 2.3 cm after TMR and temporary epiphysiodesis, and 3.1 cm after TER. In TMR group, a strong trend towards physeal recovery was observed after epiphyseal screws removal (p = 0.061), but valgus deformity in distal femur was more frequent (p = 0.049). MSTS score was good or excellent in all patients, with no statistically significant difference between TMR and TER. CONCLUSIONS: Intercalary graft reconstruction after TMR and TER allows good local disease control and excellent functional results with long-term follow-up. Temporary distal fixation might reduce the final limb discrepancy after TMR, but valgus deformity could develop. LEVEL OF EVIDENCE: Level IV.

Feasibility of microwave ablation of the vertebral growth plate for spine growth regulation: a preliminary study.

PURPOSE: To explore the feasibility of microwave ablation (MWA) of the vertebral growth plate as a minimally invasive treatment for early-onset scoliosis. MATERIALS AND METHODS: One side of the L1-L3 vertebral growth plates were ablated using different MWA powers. Ablation safety and size were examined. Subsequently, L1-L3 vertebral growth plates were ablated on one side for 40 s at 20 W. At 2, 4, and 6 weeks after the ablation, growth changes of the spine were observed. RESULTS: No piglets died during and after ablation, and all had modified Tarlov Grade 5. The safe MWA time (time for safely ablating the vertebral growth plate) was 17.0 ± 1.5 s at 50 W, 23.0 ± 2.3 s at 40 W, 31.0 ± 3.1 s at 30 W, 47.0 ± 3.7 s at 20 W, 70.0 ± 4.2 s at 15 W, and 158.0 ± 5.0 s at 10 W. With power <15 W, the vertebral growth plate could not be effectively ablated within the safe ablation time. Within the safe ablation times, the MWA size on hematoxylin and eosin slices on a transverse diameter was between 7 and 10 mm; and that on longitudinal diameter was mainly determined by the ablation needle length. Moreover, the growth plate and annulus fibrosus on the ablated side grew poorly over time, the vertebral body showed significant wedge-shaped changes, and the spine showed significant unbalanced growth. CONCLUSION: MWA of the vertebral growth plate can be performed safely when accompanied with appropriate thermometry, and could be a new minimally invasive strategy in regulating spine growth.

Physeal-sparing posteromedial portal approach reduced distance between guide pin and neurovascular structures.

PURPOSE: To compare a femoral physeal sparing anterior cruciate ligament (ACL) reconstruction technique utilizing a posteromedial portal to traditional transphyseal techniques with regards to anatomic tunnel positioning and proximity to important neurovascular structures. METHODS: Eight cadaveric knees were obtained for the study. Femoral tunnel guide pins were placed utilizing four different techniques: accessory anterior medial portal, posteromedial portal, trans-tibial, and figure-4 methods. The knees were then dissected and the following measurements taken: distance of each pin to the saphenous and peroneal nerve, popliteus tendon, neurovascular bundle, femoral ACL footprint and articular cartilage, and the angle of the guide pin entering the lateral femoral condyle. Fluoroscopic imaging was taken to determine the disruption of the physeal scar. RESULTS: Posteromedial portal guide pin was significantly closer to the neurovascular bundle, popliteal tendon and saphenous nerve when compared to the other 3 techniques, but was further from the peroneal nerve. It also had the smallest distance from the anatomic footprint of the ACL, and the largest angle to the lateral femoral condyle. The posteromedial portal guide pin had similar distance from the articular cartilage as the accessory anterior medial portal and figure-4 guide pin, with the trans-tibial guide pin being the farthest. The posteromedial portal guide pin failed to disrupt the physeal scar in all specimens, while the other three techniques consistently violated the physeal scar. CONCLUSION: The posteromedial portal technique offers an appropriate method for anatomic ACL reconstruction while protecting the distal femoral physis from injury. Care needs to be taken with this technique as it comes in closer proximity to some of the important neurovascular structures. This study indicates that posteromedial portal technique is a less technically challenging approach for physeal-sparing ACL repair with special attention required for the protection of neurovascular bundle from potential injury.

Anterior and distal tunnel orientation for anatomic reconstruction of the medial patellofemoral ligament is safer in patients with open growth plates.

PURPOSE: In patients with open growth plates, the direction of tunneling that avoids distal femoral physis (DFP) damage in anatomic reconstructions of the medial patellofemoral ligament (MPFL) has been a topic of discussion. The objective of this study was to determine the ideal orientation for anatomic reconstructions of MPFL tunneling that minimized DFP damage while avoiding breaching the intercondylar notch. METHODS: Eighty magnetic resonance images of patients aged 10 through 17 were obtained, randomly sampled from the institutional database. A de novo software was developed to obtain 3D models of the distal femur and DFP. In each model, the anatomical insertion point of the MPFL was determined as defined by Stephen. A 20-mm-depth drilling was simulated, starting from the insertion point at every possible angle within a 90° cone using 5-, 6- and 7-mm drills. Physeal damage for each pair of angles and each drill size was determined. Damage was expressed as a percentage of total physis volume. Statistical analysis was conducted using Student's t test and one-way ANOVA. RESULTS: Maximum physeal damage (5.35% [4.47-6.24]) was obtained with the 7-mm drill when drilling 3° cephalic and 15° posterior from insertion without differences between sexes (n.s.). Minimal physeal damage (0.22% [0.07-0.37]) was obtained using the 5-mm drill aimed 45° distal and 0° anteroposterior, not affected by sex (n.s.). Considering intra-articular drilling avoidance, the safest zone was obtained when aiming 30°-40° distal and 5°-35° anterior, regardless of sex. CONCLUSION: Ideal femoral tunnel orientation, avoiding physeal damage and breaching of the intercondylar notch, was obtained when aiming 30°-40° distal and 5°-35° anterior, regardless of sex. This area is a safe zone that allows anatomic MPFL reconstruction of patients with an open physis.

[Growth modulation through hemiepiphysiodesis : Novel surgical techniques: risks and progress]. / Kniegelenksnahe Wachstumsmodulation durch Hemiepiphysiodese : Neue Operationstechniken: Fortschritte und Risiken.

The correction of angular deformities of the lower limb is a key task in paediatric orthopaedic surgery. The growth potential of the physis can be employed for the correction of these malalignments in childhood and adolescence. Hemiepiphysiodesis (HED) is a surgical technique used for growth modulation by permanent or temporary asymmetrical arrest of the growth plate. In permanent HED, exact timing of the procedure is mandatory to achieve optimal correction. Temporary HED through tension band devices such as two-hole-plates or flexible staples has been established as the treatment of choice for growth guidance with excellent results. Implant-associated complications have been significantly reduced through implant modifications. Several experimental procedures have the potential to achieve growth modulation even without the requirement of surgical intervention.

Comparison of histomorphometric and radiographic effects of growth guidance with tension-band devices (eight-Plate and FlexTack) in a pig model.

Background and purpose - Temporary hemiepiphysiodesis for growth modulation in skeletally immature patients is a long-known technique. Recently the use of tension-band devices has become popular. This study compares 2 tension-band implants (eight-Plate and FlexTack) regarding their effects on the growth plate.Animals and methods - 12 pigs in 2 equally sized groups (A and B) were investigated. The right proximal medial tibia was treated with either eight-Plate or FlexTack. The left tibia of the same pig was treated with the opposite implant. After 9 weeks all implants were removed. Animals in group B were then hosted for another 5 weeks. Histomorphometric analysis of the growth plate was carried out after 9 and 14 weeks, respectively. Radiographs were taken at implantation, removal, and after 14 weeks.Results - Both tension-band devices achieved a statistically significant and clinically relevant growth inhibition, whereas the effect appeared to be more distinct after the use of FlexTack. Implant-related complications or physeal damage was not observed. After implant removal, rebound phenomenon was radiologically observed in all cases. The growth plates treated with eight-Plate showed a paradox reversal of the zonal distributions, with an increase of the proliferative zones at the previously arrested medial aspect of the physis and a decrease laterally.Interpretation - Both eight-Plate and FlexTack proved to be appropriate devices for growth-guiding treatment. The radiographic evaluation showed a change in angular axes after treatment with each implant, while the correction appeared to be faster with FlexTack. The paradox cartilaginous reaction observed after removal of the eight-Plate might be a histopathological correlate for rebound phenomenon.

The Influence of Physeal Status on Rate of Reoperation After Arthroscopic Screw Fixation for Symptomatic Osteochondritis Dissecans of the Knee.

PURPOSE: To determine if physeal status or other preoperative or intraoperative variables influence the failure rate after arthroscopic reduction and internal fixation of osteochondritis dissecans (OCD) lesions in the knee. METHODS: Consecutive patients undergoing screw fixation of osteochondral fragments from OCD by a single surgeon from 2005 to 2015 with a minimum 2-year follow-up were included. Demographic, preoperative imaging, and intraoperative data were analyzed to determine risk factors associated with failure, which was defined as the need for a revision reoperation or arthroplasty after initial OCD fixation. RESULTS: A total of 45 knees met the inclusion criteria, including 26 skeletally mature patients and 19 patients with incompletely closed physes on preoperative imaging. The mean ages of the skeletally mature and immature groups were 18.3 ± 2.5 years and 14.9 ± 2.2 years, respectively (P < .001), and the mean body mass index values were 24.3 ± 3.6 and 23.2 ± 4.0, respectively (P = .432). We excluded 10 patients from the survivorship analysis because they had less than 2 years' follow-up. No statistically significant difference in failure rates was found between skeletally mature and immature individuals (30% and 40%, respectively; P = .721). The only factor significantly associated with fixation failure was undergoing a prior surgical procedure to address the OCD lesion (P = .038). Kaplan-Meier analysis showed rates of overall survivorship from revision reoperations of 88.6% at 1 year and 68.8% at 5 years. CONCLUSIONS: Outcomes after internal fixation of OCD fragments are guarded, with a fragment survival rate of 65.7% at a mean of 4.1 years' follow-up. No difference in fragment survival was noted in skeletally mature versus immature patients. The only independent risk factor identified for fixation failure was the number of previous operations. LEVEL OF EVIDENCE: Level IV, case series with subgroup analysis.

All-epiphyseal anterior cruciate ligament reconstruction produces good functional outcomes and low complication rates in pediatric patients: a systematic review.

PURPOSE: To assess the literature on indications, outcomes, and complications in pediatric patients undergoing all-epiphyseal (AE) anterior cruciate ligament reconstruction (ACLR). METHODS: PubMed, Medline, and Embase were searched for literature evaluating AE ACLR in pediatric patients. All included studies were assessed for quality using the Methodological Index for Non-Randomized Studies (MINORS). Descriptive statistics are presented where applicable. RESULTS: Overall, 17 studies comprising 545 patients, with a mean age of 12.0 ± 1.2 (range 8-19) met the inclusion criteria. The graft choices in this systematic review included hamstring tendon autografts (75.4%, n = 403), quadriceps tendon autograft (6.2%, n = 33), Achilles tendon allograft (3.6%, n = 19) and posterior tibialis tendon allograft in one patient (0.2%, n = 1). Time of return-to-sport ranged from 8 to 22 months. Postoperative subjective IKDC scores were above 90 points. The rate of return-to-sport after AE ACLR was 93.2% (n = 219/235) and 77.9% (n = 142/183) of patients returned to sport at pre-injury level. The overall complication rate was 9.8% (n = 53/545) with the most common complication being ACL re-rupture (5.0%; n = 27/545). Only 1.5% (n = 8/545) of patients demonstrated growth disturbances. CONCLUSION: Overall, the AE ACLR technique can achieve good postoperative functional outcomes while notably minimizing the incidence of primary issue of physeal disruption and potential associated leg-length discrepancies. AE ACLR should be considered in pediatric patients with at least 2 years of skeletal growth remaining based on radiographic bone age to minimize the impact of growth-related complications. LEVEL OF EVIDENCE: IV (Systematic Review of Level III and IV evidence).

Paediatric proximal ACL tears managed with direct ACL repair is safe, effective and has excellent short-term outcomes.

PURPOSE: Anterior cruciate ligament (ACL) surgery in the paediatric population has long been a challenge. Non-operative treatment will result in persistent instability which can lead to chondral and meniscal injuries. The results of primary open ACL repair are poor. Concerns of growth plate disturbance with transphyseal techniques and issues with relatively small-diameter grafts in Tanner 1 and 2 patients, which are inadequate, have contributed to these challenges. With advancing instrumentation, there is renewed interest in ACL repair. The minimally invasive approach of arthroscopic primary ACL repair retains the native ligament. The objective and subjective outcomes at 2 years are presented. METHODS: Paediatric patients, less than 16 years of age, presenting acutely with complete proximal ACL ruptures underwent direct arthroscopic ACL repair, reinforced by a temporary internal brace, which was subsequently removed after 3 months. Patient-reported outcome measures including the Lysholm, Tegner and KOOS scores were collected at 6 months, 1 year and 2 years post-operatively. RESULTS: Twenty patients (age 6-16) completed data at 2 years post-operatively. There were no failures, no complications and no growth disturbance out to 2 years. The 2-year postoperative outcomes; Lysholm 95 (90-100), Tegner 7 (6-10), KOOS-Child 96.5 (88.9-100) demonstrated statistically significant improvements following surgery (p < 0.001). Objective measurements with an accelerometer did not demonstrate any significant side-to-side difference. CONCLUSION: ACL repair for proximal ACL tears in the paediatric population demonstrates the potential for excellent outcomes at short-term follow-up. This presents an attractive alternative to ACL reconstruction when an adequate ACL remnant permits direct repair. Our results demonstrate that paediatric ACL repair is safe and effective.

Anterior Cruciate Ligament Injuries in Skeletally Immature Patients: A Meta-analysis Comparing Repair Versus Reconstruction Techniques.

BACKGROUND: Anterior cruciate ligament (ACL) surgery remains challenging in the skeletally immature patient. Despite the widespread use of physeal-sparing reconstruction techniques, there has been renewed interest in the ACL repair. The purpose of this study was to systematically review the literature to better understand outcomes following all-epiphyseal (AE) reconstruction to extraphyseal reconstruction, while also evaluating ACL repair outcomes in skeletally immature patients. METHODS: Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, all studies in the literature from January 1970 to August 2019 reporting on skeletally immature patients undergoing ACL surgery were identified. Inclusion criteria were pediatric patients with open physes indicative of skeletal immaturity sustaining complete ACL ruptures treated with AE reconstruction, extraphyseal reconstruction or ACL repair. Chronologic age, bone age, postoperative outcomes scores, return to sport rate, and the incidence of complications, namely reruptures, were analyzed. RESULTS: A total of 14 studies comprising 443 patients were identified. No significant difference in chronologic age or postoperative outcome scores at final follow-up were appreciated between patients undergoing AE versus extraphyseal reconstruction. Return to activity rate was significant greater following extraphyseal reconstruction when compared with AE reconstruction. The incidence of any limb-length discrepancies and limb discrepancies measuring ≥10 mm were significant higher following AE reconstruction, while rerupture rates were more common following AE reconstruction. CONCLUSIONS: Patients undergoing AE reconstruction possessed significantly lower return to activity rates, higher incidences of limb-length discrepancies and more commonly experienced ACL reruptures when compared with patients undergoing extraphyseal reconstruction. Further investigations analyzing results following ACL repair in skeletally immature patients are warranted to allow for the comparison of outcomes with current physeal-sparing reconstruction techniques. LEVEL OF EVIDENCE: Level IV-systematic review-therapeutic study.

Distal Femoral Physeal Bar Resection Combined With Guided Growth for the Treatment of Angular Limb Deformity Associated With Growth Arrest: A Preliminary Report.

PURPOSE: Distal femoral growth arrest can result in progressive deformities and functional disability. The treatment is challenging given the significant growth potential of the distal femoral physis. This study addresses the short-term outcomes after distal femoral physeal bar resection combined with guided growth for the treatment of angular limb deformity. METHODS: We conducted a retrospective analysis of patients treated with distal femoral physeal bar resection, fat graft interposition, and growth modulation with a tension-band plate. Data recorded included patient demographics, growth arrest cause, physeal bar size, time-to-surgery, details of the operative procedure, and complications. The mechanical axis zones, tibiofemoral angle, and the anatomic lateral distal femoral angle were assessed on 51-inch anteroposterior standing radiographs. RESULTS: Five patients (3 male individuals) with valgus (n=4) and varus deformities (n=1) due to physeal arrests of the distal femur were analyzed. The cause of the physeal arrest was trauma (n=3) and infection (n=2). The average age at the time of surgery was 6.6 years (range: 2 to 11 y). Average size of the physeal bar was 413.4 mm, which represented 16.8% of the total distal femoral physis (range: 12% to 26%). Four of the 5 patients had a total correction of the deformity in 14.3 months (range: 9 to 22 mo). One patient required correction by osteotomy and external fixation. Postoperatively, 1 patient presented no improvement, and 4 had restoration of the longitudinal bone growth and alignment. Two patients had rebound valgus: one is being observed and another has undergone a repeat guided growth procedure. CONCLUSIONS: Distal femoral physeal bar resection combined with tension-band hemiepiphysiodesis provides a viable option for the correction of angular deformities associated with physeal arrest. Longer follow-up is required to evaluate future growth of the distal femoral physis after this combined procedure. LEVEL OF EVIDENCE: Level IV-therapeutic study.