A comprehensive MRI investigation to identify potential biomarkers of Osgood Schlatter disease in adolescents: A cross sectional study comparing Osgood Schlatter disease with controls

BACKGROUND

Osgood-Schlatter disease (OSD) is the most common knee pain complaint among adolescents playing sports. Despite this, there remains controversy over the pathophysiology and whether specific anatomical characteristics are associated with OSD.

PURPOSE

This study aimed to systematically and comprehensively characterize adolescents with OSD using magnetic resonance imaging (MRI) compared to pain-free controls, including both tissue abnormalities that may be associated with OSD, as well as anatomical characteristics. A secondary objective was to identify potential imaging biomarkers associated with pain.

STUDY DESIGN

Cross-sectional study.

METHODS

Adolescents with OSD and controls were recruited from 2020 to 2022. Following a clinical exam, demographics, pain, sports participation, and Tanner stage were collected. Knee MRI was conducted on the participants' most symptomatic knee (OSD) or the dominant leg (controls).

RESULTS

Sixty-seven adolescents (46 with OSD and 30 controls) were included. 80% of participants with OSD had at least one tissue alteration compared to 54% of controls. Compared to controls, OSD had 36.3 (95%CI 4.5 to 289.7) higher odds of bony oedema at the tibial tuberosity, and 32.7 (95%CI 4.1 to 260.6) and 5.3 (95%CI 0.6 to 46.2) higher odds of bony oedema at the  tibial epiphysis and metaphysis respectively. Participants with OSD also had higher odds of fluid/oedema at the patellar tendon (12.3 95%CI 3.3 to 46.6), and superficial infrapatellar bursitis (7.2).  Participants with OSD had a more proximal tendon attachment (mean tibial attachment portion difference, -0.05, 95% CI: -0.1 to 0.0, p = 0.02), tendon thickness (proximal mean difference, -0.09, 95% CI: -0.4 to 0.2, p = 0.04; distal mean difference, -0.6, 95% CI: -0.9 to -0.2, p = 0.01). Those with bony/tendon oedema had 1.8 points (95% CI: 0.3 to 3.2) higher pain on palpation than those without (t = -2.5, df = 26.6, p = 0.019), but there was no difference between these groups in a functional single leg pain provocation.

CONCLUSION

Adolescents with OSD present with tissue and structural abnormalities on MRI that differed from age-matched controls. The majority had findings in the patellar tendon and bone, which often co-occurred. However, a small proportion of OSD also presents without alterations. It appears these findings may be associated with clinical OSD-related pain on palpation of the tibial tuberosity.

CLINICAL RELEVANCE

Our highlight the pathophysiology on imaging, which has implications for understanding the mechanism and treatment of OSD.

Increased tibial tuberosity torsion has the greatest predictive value in patients with patellofemoral instability compared to other commonly assessed parameters

PURPOSE

The multifactorial nature of patellofemoral instability requires a comprehensive assessment of the affected patients. While an association between tibial tuberosity (TT) torsion and patellofemoral instability is known, its specific effect has not yet been investigated. This study investigated the effect of TT torsion on patellofemoral instability.

METHODS

This retrospective cohort study compared patients who underwent surgical intervention for patellofemoral instability and asymptomatic controls. TT torsion was measured in addition to other commonly assessed risk factors for patellofemoral instability using standardised computed tomography (CT) data of the lower extremities. The diagnostic performances of the assessed parameters were evaluated using receiver operating characteristic curve analysis and odds ratios (ORs) were calculated.

RESULTS

The patellofemoral instability group consisted of 79 knees, compared to 72 knees in the asymptomatic control group. Both groups differed significantly in all assessed parameters (p < 0.001), except for tibial torsion (n.s.). Among all parameters, TT torsion presented the best diagnostic performance for predicting patellar instability with an area under the curve of 0.95 (95% confidence interval [CI], 0.91-0.98; p < 0.001). A cut-off value of 17.7° yielded a 0.87 sensitivity and 0.89 specificity to predict patellar instability (OR, 55.2; 95% CI, 20.5-148.6; p < 0.001).

CONCLUSION

Among the evaluated risk factors, TT torsion had the highest predictive value for patellofemoral instability. Patients with TT torsions ≥ 17.7° showed a 55-fold increased probability of patellofemoral instability. Therefore, TT torsion should be included in the assessment of patients with patellofemoral instability.

LEVEL OF EVIDENCE

Level III.

Tibial Tubercle Avulsion Fractures in Adolescence in Sports Injury about Four Cases Series

Introduction

Tibial tubercle avulsion fractures are a rare lesion in adolescence that occurs during sports such as basketball, soccer, and volleyball. They result from a forceful extension of the knee against a fixed leg.

Case Report

Case 1: A 14-year-old adolescent who reportedly experienced severe knee pain when he jumped to head a ball during a soccer game. Case 2: A 17-year-old teenager who reportedly experienced severe knee pain on takeoff during a high jump event. Case 3: A 16-year-old who reportedly felt pain during takeoff to catch a basketball. Case 4: A 14-year-old adolescent who reportedly felt pain in his left knee on takeoff from a high jump during a basketball game. All of these patients presented with a defective leg extension on clinical examination. Radiographs showed an avulsion fracture of the anterior tibial tuberosity and treatment was surgical.

Discussion

Avulsion fractures of the tibial tuberosity are rare lesions. They occur in adolescents during sports and are usually accompanied by fracture fragment displacement, indicating reduction, and internal fixation surgery by screwing. In the short term, the result is satisfactory.

Conclusion

Tibial tuberosity avulsion fractures when managed in their entirety, give better results with a precocious return to sport.

ENPP1 downregulation and FGF23 upregulation in growth-related calcification of the tibial tuberosity in rats

During tibial tuberosity growth, superficial and deep portions can be observed; however, the deep portion is not observed after the growth period, as it develops into bone tissues. Calcification in vivo is known to be constitutively suppressed by ectonucleotide pyrophosphatase/phosphodiesterase-1 (ENPP1) but promoted by tissue-nonspecific alkaline phosphatase (TNAP). FGF23 promotes calcification of enthesis. Gene expression of FGF23 increased rapidly at 13W in this study. Therefore, the tibial tuberosity is speculated to develop via Enpp1 downregulation and Tnap upregulation; however, the understanding of these processes remains unclear. Hence, in the present study, we aimed to explore the age-related structural changes and underlying gene expression changes in the tibial tuberosity of rats. Male Wistar rats were divided into three groups (3-, 7-, and 13-week-old; eight each). The tibial tuberosity superficial and deep portions were clearly observed in 3- and 7-week-old rats, but the presence of the deep portion was not confirmed in 13-week-old rats. The extracellular matrix of hypertrophic chondrocytes was calcified. Furthermore, the Enpp1 expression was the highest in 3-week-old rats and decreased with growth. The TNAP expression did not differ significantly among the groups. The deep portion area was significantly lower in 3-week-old rats than in 7-week-old rats. Generally, the extracellular matrix of the immature chondrocytes is not calcified. Therefore, we speculated that the cartilaginous tibial tuberosity calcifies and ossifies with growth. The Enpp1 expression decreased with growth, whereas the Tnap expression remained unchanged. Thus, we surmise that the tibial tuberosity calcifies with growth and that this process involves Enpp1 downregulation and FGF23 upregulation. As Osgood-Schlatter disease is closely related to the calcification of the tibial tuberosity, these findings may help clarify the pathogenesis of this disease.

Bilateral Tibial Tuberosity Periosteal Sleeve Fracture in an Adolescent: A Case Report

Tibial tuberosity avulsion fracture is a rare injury, and bilateral occurrence is more uncommon. Periosteal sleeve fracture is a unique fracture pattern which was first described in the lower pole of patella in children. We are reporting a rare case of bilateral tibial tuberosity sleeve fracture in a teenage boy which occurred while sprinting. The patient underwent open reduction, pull through suture fixation of the bilateral tibial tuberosity and screw fixation of left tibial tuberosity. Post-operative rehabilitation included gradual increment of range of motion with hinged brace and quadriceps muscle strengthening. Close follow-up was done to monitor the progression of his recovery. At six months follow-up, the patient recovered well. Both knees had full range of motion with an intact extensor mechanism.

Isolated Avulsion Fracture of the Tibial Tuberosity in an Adult Treated with Suture-Bridge Fixation: A Rare Case and Literature Review

Background and objectives: Isolated tibial tuberosity avulsion fractures are exceptionally uncommon among adults, with limited instances documented in published literature. Here, we describe a case of an isolated tibial tuberosity avulsion fracture in an adult that was treated successfully with the suture bridge repair technique. Patient concerns: A 65-year-old female visited the outpatient department with left knee pain after a slip and fall. Lateral radiographs and sagittal MR images of the left knee revealed the tibial tuberosity avulsion fracture, but the fracture line did not extend into the knee joint space. Surgical intervention was performed on the patient's knee using an anterior midline approach, involving open reduction and internal fixation. The avulsed tendon was grasped and pulled, and an appropriate suture location was identified. Using a suture hook, the suture was guided through the patellar tendon as near to its uppermost point of the fragment as achievable, and tied over tendon. A single suture limb from each anchor was fastened over the tibial tuberosity to the distally positioned foot print anchor, effectively anchoring the tibial tuberosity using the suture bridge technique. The patient started walking on crutches after one week and was able to walk independently with a brace after two weeks from the operation day. After three months, the patient had regained her mobility to the level prior to the injury and exhibited painless active range of motion from 0 to 130 degrees. Hardware positioning and bony union were maintained at the one-year follow-up. Conclusions: In our case, the open suture bridge fixation method for tibial tuberosity avulsion fractures produced satisfactory results. Open suture bridge fixation may be considered for isolated tibial tuberosity avulsion fractures in adults, especially when the avulsion tip is too small for screw fixation.

Reliability of the TT-TG Index Versus TT-TG Distance on MRI: Morphometric Analyses in Asian Children and Adolescents

Background

The tibial tuberosity-trochlear groove (TT-TG) distance measured on magnetic resonance imaging (MRI) is commonly used to decide the treatment for patellar instability; however, the patient's joint size is not considered in this measurement. The TT-TG index has been proposed as a knee size-adjusted measurement for tibial tuberosity location.

Purpose

To evaluate the reliability of the TT-TG index compared with the TT-TG distance by analyzing variations in measurement according to age and sex in a pediatric Asian population.

Study Design

Cohort study (diagnosis); Level of evidence, 3.

Methods

A total of 698 knee MRI scans were collected in patients between 4 and 18 years of age who did not have any patellofemoral problems. Patient age, sex, height, and weight were recorded. The scans were divided into 5 groups according to patient age (4-6 years, 46 scans; 7-9 years, 56 scans; 10-12 years, 122 scans; 13-15 years, 185 scans; and 16-18 years, 289 scans); MRI scans were also divided by sex (497 male, 201 female). Three independent observers measured the TT-TG distance and TT-TG index on each scan, and age- and sex-based differences in the measurements were evaluated after adjusting for body mass index (BMI). The reliability of the measurements was calculated with the intraclass correlation coefficient (ICC).

Results

Good to excellent inter- and intraobserver agreement was found for TT-TG distance (ICC, 0.74) and TT-TG index (ICC, 0.88). The TT-TG distance was significantly different among the groups and increased with age, while variations in the TT-TG index were minimal between age groups and sexes. This finding was also consistent after compensating for the effect of BMI.

Conclusion

The TT-TG distance changed with age, while the TT-TG index was relatively constant. Therefore, the TT-TG index may be more reliable and effective for diagnosing and planning treatment, especially in children and adolescents.

The Tibial Tuberosity-Rotational Angle as a Novel Predisposing Parameter for Patellar Dislocation

Background

The tibial tuberosity (TT) in the axial plane is located on a curved line along the anterior cortex of the proximal tibia. Therefore, the linear measurement of TT position may not fully reflect TT malposition.

Purpose

To introduce TT-rotational angle (TT-RA) as a new anatomical parameter, which means the rotation of the TT relative to the dorsal condylar line of the tibia, and to validate its predictive value for patellar dislocation.

Study Design

Cross-sectional study; Level of evidence, 3.

Methods

Included were 46 patients with a history of patellar dislocation and 46 age- and sex-matched controls who underwent axial magnetic resonance imaging. Seven radiological parameters were measured and compared between the 2 groups, including TT-trochlear groove (TT-TG) distance, tibial tubercle-posterior cruciate ligament (TT-PCL) distance, TT-PCL ratio, TT lateralization (TTL), trochlear groove medialization (TGM), TT-RA, trochlear groove-posterior condylar axis angle (TG-PCA), and knee rotation. The predictive values of parameters for patellar dislocation were assessed using multiple logistic regression analysis.

Results

The intra- and interobserver correlation coefficients for measuring the radiographic parameters showed good to excellent values., respectively. There were significant differences in the TT-TG distance (13.9 vs 6.8 mm; P < .001), TT-RA (16.0° vs 9.1°; P < .001), TG-PCA (93.7° vs 95.4°; P = .017), and knee rotation (0.9° vs 5.3°; P < .001) between the 2 groups. However, there was no significant difference in TT-PCL distance (20.7 vs 19.4 mm; P = .075), TT-PCL ratio (28.0% vs 26.6%; P = .136), TTL (65.7% vs 64.9%; P = .270), or TGM (54.9% vs 55.0%; P = .923). Multivariable analysis showed that 3 parameters were significantly associated with patellar dislocation: TT-RA (OR, 1.57; P < .001), TT-TG distance (OR, 1.52; P = .002), and knee rotation (OR, 0.75; P = .022).

Conclusion

The TT-RA was a reliable predisposing parameter of patellar instability. It can be an alternative method of measurement when the TT-TG distance is not clearly defined.

A novel technique of tibial tuberosity fracture fixation with two knotless suture anchors in an adult: A case report and literature review

Tibial tuberosity fractures are uncommon in adults. Surgery for these types of fractures is performed similarly to that of tibial tuberosity avulsion fractures in adolescents. The most commonly introduced method is to fix the displaced bone fragments using screws or wires and, if necessary, use tension band wiring for augmentation. However, if the bone fragments are too small or severely comminuted, it may be challenging to fix them using the conventional method. In this study, we introduced a fixation method using two knotless suture anchors that could be attempted in such cases. Since this surgical method fixes the bone fragments without direct damage to the bone fragments, it can be used even when the fragments are small or comminuted. This technique achieved a nearly full active range of knee motion without an extension lag at four weeks postoperatively. In addition, there were no complications related to surgery, and a complete bone union was achieved without additional dislocation. Therefore, this surgical method may be a good alternative if a fixation of the fracture is considered problematic by the conventional method.

Correlation Between Anatomic Landmarks and Bony Trough Position in Lateral Meniscal Allograft Transplant

Background

Determining the rotational axis of the bony trough during lateral meniscal allograft transplant (MAT) is difficult. The use of anatomic landmarks may help a surgeon determine the rotational alignment of the graft during the procedure.

Purpose

To investigate the association between the knee's anatomic landmarks and the position of the bony trough to prevent extrusion after lateral MAT.

Study Design

Cross-sectional study; Level of evidence, 3.

Methods

Enrolled were 44 patients who underwent lateral MAT between July 2000 and February 2011. The patients' mean age at the time of surgery was 30.8 years. Extrusion was measured on magnetic resonance imaging (MRI) scans at a mean of 3.6 months postoperatively, and patients were divided into an extrusion group (n = 15) and a no-extrusion group (n = 29). Three coronal MRI scans from each patient were selected, each from the region at the level of the tibial tuberosity (TT), the anterior bony trough, and the posterior bony trough. We measured the distance between the center of the anterior bony trough and the center of the TT (the TT distance) and the distance between the center of the posterior bony trough and the medial border of the lateral femoral condyle (LFC) (the LFC distance).

Results

The mean center of the anterior bony trough was in a more medial position relative to the center of the TT in the no-extrusion group (-2.9 ± 4.8 mm) compared with the extrusion group (1.3 ± 4.9 mm; P = .010). The mean center of the posterior bony trough was in a more medial position relative to the medial border of the LFC in the no-extrusion group (-1.7 ± 3.9 mm) compared with the extrusion group (1.0 ± 3.2 mm; P = .027). Both TT distance and LFC distance were significantly correlated with extrusion (P = .005 and .025, respectively). The cutoff value was -0.24 mm for the anterior bony trough and -0.58 mm for the posterior bony trough (negative values indicate that the trough was medial to the respective landmarks).

Conclusion

To prevent extrusion of the allograft, the center of the anterior bony trough needs to be aligned with the center of the TT, and the center of the posterior bony trough needs to be aligned with the medial border of the LFC.

Clinical validation of the Oswestry-Bristol Classification as part of a decision algorithm for trochlear dysplasia surgery

AIMS

The Oswestry-Bristol Classification (OBC) is an MRI-specific assessment tool to grade trochlear dysplasia. The aim of this study is to validate clinically the OBC by demonstrating its use in selecting treatments that are safe and effective.

METHODS

The OBC and the patellotrochlear index were used as part of the Oswestry Patellotrochlear Algorithm (OPTA) to guide the surgical treatment of patients with patellar instability. Patients were assigned to one of four treatment groups: medial patellofemoral ligament reconstruction (MPFLr); MPFLr + tibial tubercle distalization (TTD); trochleoplasty; or trochleoplasty + TTD. A prospective analysis of a longitudinal patellofemoral database was performed. Between 2012 and 2018, 202 patients (233 knees) with a mean age of 24.2 years (SD 8.1), with recurrent patellar instability were treated by two fellowship-trained consultant sports/knee surgeons at The Robert Jones and Agnes Hunt Orthopaedic Hospital. Clinical efficacy of each treatment group was assessed by Kujala, International Knee Documentation Committee (IKDC), and EuroQol five-dimension questionnaire (EQ-5D) scores at baseline, and up to 60 months postoperatively. Their safety was assessed by complication rate and requirement for further surgery. The pattern of clinical outcome over time was analyzed using mixed regression modelling.

RESULTS

In all, 135 knees (mean age 24.9 years (SD 9.4)) were treated using a MPFLr. Ten knees (7.4%) required additional surgery. A total of 50 knees (mean age 24.4 years (SD 6.3)) were treated using MPFLr + TTD. Ten (20%) required additional surgery. A total of 20 knees (mean age 19.5 years (SD 3.0)) were treated using trochleoplasty + TTD. Three patients (15%) required additional surgery. In each treatment group, there was a significant improvement in Kujala, IKDC, and EQ-5D at one year postoperatively (p < 0.001) with a recognized level of overall complication rate.

CONCLUSION

The OBC is a valid assessment tool to grade patients with trochlear dysplasia and, when used as part of the OPTA, helps to determine treatments that are safe and effective. This fulfils the requirements for its application in mainstream clinical practice. Cite this article: Bone Joint J 2021;103-B(10):1586-1594.

Tibial tuberosity ossification predicts reoperation for growth disturbance in distal femoral physeal fractures

PURPOSE

Distal femoral physeal fractures (DFPF) can cause growth disturbance that requires further surgical intervention. The aim of this study is to determine if Tibial Tuberosity Ossification Stage (TTOS) at the time of injury predicts secondary surgery for growth disturbance in patients who have sustained a DFPF.

METHODS

We retrospectively investigated all patients who had operative treatment for a DFPF at a single centre over a 17-year period. Regression analysis was performed investigating associations between secondary surgery to treat growth disturbance and TTOS, age, Salter-Harris fracture classification type, mode of fixation or mechanism of injury.

RESULTS

In all, 85 consecutive patients were identified. A total of 74 met the inclusion criteria. The mean age at time of injury was 13.1 years (2.0 to 17.1). Following fixation, 30 patients (41%) underwent further surgery to treat growth disturbance. Absence of tibial tuberosity fusion to the metaphysis was significantly associated with the need for further surgery (p < 0.001). Odds of requiring secondary surgery after tibial tuberosity fusion to metaphysis (compared with not fused) were 0.12 (95% confidence interval (CI) 0.04 to 0.34). The estimate of the effect of TTOS on reoperation rates did not vary when adjusted for gender, mechanism, fixation and Salter-Harris type. When accounting for age, the odds of any further operation if the tibial tuberosity is fused to the metaphysis (compared with not fused) were 0.28 (95% CI 0.08 to 0.94).

CONCLUSION

TTOS at the time of injury is a predictor of further surgery to treat growth disturbance in paediatric distal femoral fractures.

LEVEL OF EVIDENCE

Diagnostic Level II.

Screening of the Maturity Status of the Tibial Tuberosity by Ultrasonography in Higher Elementary School Grade Schoolchildren

This study aimed to obtain screening data on the maturity status of the tibial tuberosity in schoolchildren of higher elementary school grades for risk management of Osgood-Schlatter disease (OSD). The maturity stages and cartilage thicknesses at the tibial tuberosity were determined by ultrasonography on the occasion of a school-based musculoskeletal examination for 124 grade 5-6 elementary schoolchildren, and their associations with the students' demographic characteristics and OSD were examined. The time-dependent changes of the maturity status of the tibial tuberosity were also examined in grade 5 students (n = 26) by a longitudinal survey. The cross-sectional survey showed that the epiphyseal stage was reached in 89% of girls and 35% of boys. The girls who had experienced menarche (n = 28) were all in the epiphyseal stage and had a decreased cartilage thickness (p = 0.004, after adjusting maturity stages). Students with OSD (n = 5) were all girls in the epiphyseal stage, and only two of them had an increased cartilage thickness. During the longitudinal survey, a marked increase in cartilage thickness from the previous measurement was observed in three boys (without clinical symptoms) and a girl who newly developed OSD. Two students with OSD without chronic pain had thin cartilage. In conclusion, for schoolchildren of higher elementary school grades, the risk of OSD is higher among girls with the epiphyseal stage. Cartilage thickness may not contribute to the diagnosis of OSD, since thick cartilage is not very common in OSD. However, cartilage thickness may reflect the status of OSD.

Distalization and Medialization of Tibial Tuberosity for the Treatment of Potential Patellar Instability with Patella Alta

Purpose  The aim of the study was to test the distalization and medialization of the tibial tuberosity (DMTT) for the treatment of patellar instability associated with patella alta, focusing on residual instability and pain. Methods  Twenty-four consecutive patients (26 knees) suffering from patellofemoral instability and patella alta were treated by DMTT. Two groups were identified, which differed for documented history of frank patella dislocation. The groups were named objective patellar instability (OPI) (history of dislocation) and potential patella instability (PPI) (no dislocation). Outcome was measured with visual analogue scale (VAS), Kujala score, and Tegner score. Comparison between groups was performed using Student's t -test, Wilcoxon rank score, and Fisher's exact test (significance at p  < 0.05). Results  At 50 ± 18 and 41 ± 18 months of follow-up, respectively, both PPI and OPI groups obtained a significant pain reduction and functional improvement. The PPI group showed a significant decrease of the subjective instability. No procedure-related complications were reported. Conclusion  This study suggests that DMTT is a viable option for PPI patients with patella alta. The outcome was comparable between PPI and OPI cases; however, decrease in subjective instability was significantly greater in PPI patients. Level of Evidence  Level III, retrospective comparative study.

Surgical Treatment With Closing-Wedge Distal Femoral Osteotomy for Recurrent Patellar Dislocation With Genu Valgum

BACKGROUND

Closing-wedge distal femoral osteotomy (CWDFO)-combined with medial reefing and lateral release, if necessary- has been used to treat recurrent patellar dislocation (RPD) with genu valgum.

PURPOSE

To evaluate the clinical and radiologic outcomes of surgical treatment with CWDFO for treatment of RPD with genu valgum.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Fourteen consecutive patients (23 knees) with RPD and genu valgum were treated with CWDFO. Patients with a minimum 2-year follow-up period were eligible for this study. Patients with prior failed surgery were also eligible. Radiographic evaluation was performed with mechanical femorotibial and lateral distal femoral angle. The radiographic parameters presenting patellar positions and pathologic abnormalities associated with RPD were evaluated. Chondral lesion changes in second-look arthroscopic examination were examined, and clinical outcomes (eg, occurrence of redislocation, range of motion, and clinical scores) were assessed pre- and postoperatively at a minimum of 2 years.

RESULTS

At a mean follow-up of 30.7 months (range, 25-62 months), the mean mechanical femorotibial and mechanical lateral distal femoral angles changed significantly from valgus 5° (range, 2°-11°) to varus 3° (2°-11°; P < .001) and from 83° (range, 78°-86°) to 89° (84°-92°; P < .001), respectively. The mean patellar congruence angle improved from 40° lateral (range, 20°-53° lateral) to 4° medial (23° medial to 21° lateral; P < .001), as did the lateral patellofemoral angle from 26° (range, 8°-62°) to 9° (0°-15°; P < .001). Computed tomography scans showed that the mean distance of patellar lateral shift decreased from 13.5 mm (range, 4-22 mm) to 2.0 mm (-4 to 5 mm; P < .001). The mean tibial tubercle to trochlear groove distance significantly decreased from 20.4 to 13.5 mm ( P < .001), while the Caton-Deschamps ratio did not change significantly after surgery ( P = .984). Chondral lesions of the patella and trochlear groove significantly improved or were maintained. None of the patients experienced subluxation or redislocation after surgery. Patellar instability symptoms also improved, as validated by radiographic and other clinical outcomes.

CONCLUSION

CWDFO combined with medial reefing and lateral release successfully treated RPD with genu valgum for a minimum follow-up of 2 years, with improved patellar alignment and stability.

Bony Maturity of the Tibial Tuberosity With Regard to Age and Sex and Its Relationship to Pathogenesis of Osgood-Schlatter Disease: An Ultrasonographic Study

BACKGROUND

Although tensile force on an immature tibial tuberosity is considered the main cause of Osgood-Schlatter disease (OSD), the relationship between bony maturity and the pathogenesis of OSD remains obscure.

PURPOSE

To survey the bone maturation process of the tibial tuberosity by age and sex and clarify its relationship to OSD.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

A total of 731 Japanese basketball players aged 6 to 14 years were enrolled in this study. Ultrasonographic examination was performed in all participants (1462 knees) to evaluate the bony maturity of the tibial tuberosity by use of the Ehrenborg classification. The age- and sex-specific prevalence of each stage was investigated, and the prevalence of symptomatic OSD and its relationship with bony maturity were also assessed.

RESULTS

The process of bone maturation occurred 1 to 2 years earlier in female participants compared with male participants. Among female participants, 59.2% were already at the epiphyseal stage (stage E) by 10 years of age, and 47.4% were skeletally mature by 14 years. Among male participants, conversely, only 8.0% were at stage E by 10 years of age, and only 13.8% were skeletally mature by 14 years. The overall prevalence of symptomatic OSD was 6.8% (males, 6.4%; females, 7.2%), and the onset was 1 year earlier in the female participants. The prevalence of symptomatic OSD tended to increase with age and bony maturity, significantly increasing from the cartilaginous stage (stage C) to the apophyseal stage (stage A) (odds ratio, 9.48) and from stage A to stage E (odds ratio, 2.22).

CONCLUSION

The tibial tuberosity matures earlier in female participants. The risk of OSD is greater in stage A than stage C and in stage E than stage A. The risk of OSD increases with age in males but not in females.

[Osgood-Schlatter disease in adolescent athlete. Case report]

Knee pain is one of the most frequent musculoskeletal symptoms in young physically active males. Common entities of clinical diagnosis as osteochondritis/apophysitis and others that need complementary studies should be considered in the differential diagnosis. We present the case of a 12-year-old male athlete with continuous pain in his right knee that intensifies with physical activity and with direct pressure. Diagnosis of Osgood-Schlatter disease is made by exploratory data, pain-to-finger palpation on the anterior tibial tuberosity, and is confirmed by radiology. This entity is described as well as the main pathologies derived from overuse to make differential diagnosis and to stress preventive measures regarding a correct orientation in the sport activity.

Apophysitis of the Tibial Tuberosity (Osgood-Schlatter Disease): A Review

Osgood-Schlatter disease (OSD) is a condition in which the patellar tendon insertion on the tibial tuberosity becomes inflamed. It is a well-known condition in late childhood characterized by pain and a bony prominence over the tibial tuberosity. The pain is usually exacerbated by physical activities like running, jumping, and climbing stairs. In the acute stage, the margins of the patellar tendon become blurred in radiographs due to the soft tissue swelling. After three to four months, bone fragmentation at the tibial tuberosity is viewed. In the sub-acute stage, soft tissue swelling resolves, but the bony ossicle remains. In the chronic stage, the bone fragment may fuse with the tibial tuberosity which can appear normal.

The primary goal in the treatment of OSD is the reduction of pain and swelling over the tibial tuberosity. The patient should limit physical activities until the symptoms are resolved. In some cases, the patient should restrict physical activities for several months. The presence of pain with kneeling because of an ossicle that does not respond to conservative measures is the indication for surgery. In these cases, the removal of the ossicle, surrounding bursa, and the bony prominence is the treatment of choice.

Relationship between the clinical findings and radiographic severity in Osgood-Schlatter disease

BACKGROUND

Osgood-Schlatter disease (OSD) is one of the common causes of knee pain in active adolescents who play sports. The common age for boys to have OSD is between 12 and 15 years and for girls, between 8 and 12 years. Radiographic studies are helpful in diagnosis and treatment of OSD.

PURPOSE

We examine the age at onset of OSD in detail and investigate the relationship between clinical findings, radiographic bone morphology, and the severity of OSD in adolescents.

RESULTS

The average age at onset of knee pain was 12 years and 6 months - 12 years and 9 months in boys, and 12 years and 1 month in girls. Boys were significantly older than girls at onset. In addition, there were significant relationships between duration from first onset to visit to the clinic, radiographic bone stage, body morphology, and radiographic severity. The patients who delayed their visit to the clinic from the first onset of pain and who were older showed a later bone stage and more radiographic severity grade of OSD. There was significant differences concerning weight and body mass index between severity grade I and III.

CONCLUSION

For the age at the onset of OSD, the mean age of boys was significantly older than that of girls. The patients at a later bony stage had a higher severity grade. The boys and girls with OSD who had less weight or body mass index showed less severity.

Tibial tuberosity fractures in adolescents

BACKGROUND

Tibial tuberosity fractures in adolescents are uncommon. We retrospectively reviewed all tibial tuberosity fractures in adolescents (10-19) who presented to our level 1 pediatric trauma center over a 7-year period to review fracture morphology, mechanism of injury, fracture management including return to play, as well as complications. Additionally, we present a review of the literature and treatment algorithm.

METHODS

We reviewed the clinical charts and radiographs of consecutive patients with tibial tuberosity fractures between 01 January 2000 and 01 January 2007. Data parameters included the following: patients age and gender, involved side, injury classification, co-morbidities, mechanism of injury, treatment, return to activity and complications. Data were extracted and reviewed, and a treatment algorithm is proposed with some additional insights into the epidemiology of the injury. Nineteen patients met the inclusion criteria.

RESULTS

There were 19 patients with 20 tibial tuberosity fractures. The mean age was 13.7 years. There were 18 males and 1 female patient. There were nine left-sided injuries and eleven right-sided including one patient with bilateral fractures. Mechanism of injuries included basketball injury (8), running injury (5), football injury (3), fall from a scooter (2), high jump (1) and fall (1). Co-morbidities included three patients with concurrent Osgood-Schlatter disease and one with osteogenesis imperfecta. All were treated with ORIF, including arthroscopic-assisted techniques in two cases. Complications included four patients with pre-operative presentation of compartment syndrome all requiring fasciotomy, one post-operative stiffness and one painful hardware requiring removal. Range of motion was started an average of 4.3 weeks post-operatively and return to play was an average of 3.9 months post-operatively.

CONCLUSION

Although uncommon, tibial tuberosity fractures in adolescents are clinically important injuries. Early recognition and treatment (closed or open as appropriate) gives good results. All the patients in our series had surgical fixation as per different indications that have been elaborated. It is important for clinicians to recognize that compartment syndrome remains a significant concern post-injury and in the perioperative period. Close monitoring and timely intervention is recommended. A simple treatment algorithm is presented for clinicians to help manage these injuries.