Does an early post traumatic knee brace reduce the incidence of knee rotational instability?

PURPOSE: Several anterolateral stabilization procedures have been developed recently to address rotational instability of the knee. Currently, these procedures tend to be systematically used by some practitioners. However, antero-lateral structures of the knee (including the anterolateral ligament, ALL) have a self-healing potential which can reduce the need to perform an antero-lateral procedure. In this study, it was hypothesized that early post-traumatic immobilization of the knee with a knee brace would allow partial healing of antero-lateral structures and also allow control of the pivot shift, thus avoiding antero-lateral extra-articular stabilization. The objective of this study was to compare the severity of pivot shift between two groups of patients who all experienced anterior cruciate ligament (ACL) tear and respectively underwent post-traumatic immobilization of the knee versus no immobilization. METHODS: This was a comparative, multicentric (three centers' study) retrospective, consecutive study including 168 patients who underwent ACL reconstruction between May and September 2022. The application or not of post-traumatic immobilization and its duration, the severity of pivot shift observed in the operating room under general anesthesia, the presence of anterolateral lesions as revealed by MRI and the patients' pre-injury sport activity were recorded. RESULTS: A grade 3 pivot shift was found in 44 patients (27%). It was more frequently observed in the group without a brace compared to the group with a knee brace (18 patients out of 36: 50% versus 26 patients out of 132: 19.7%; p = 0.0012). Wearing a brace, whether hinged (OR = 0.221, [0.070-0.652]; p = 0.006) or not (OR = 0.232, [0.076-0.667]; p = 0.0064), was protective from the risk of developing a significant pivot shift. CONCLUSION: This study demonstrated that the presence of pivot-shift was lower in the patients that had an early post-injury knee brace before their ACL reconstruction. Based on this result, systematic brace placement could be advocated for in patients after knee trauma. LEVEL OF EVIDENCE: III, prognostic retrospective case-control study.

Variable rotation of the femur does not affect outcome with patient specific alignment navigated balanced TKA.

PURPOSE: Excessive internal and external rotation of the femoral component has been associated with poor outcome with a measured-resection neutral mechanical alignment TKA. This technique assumes that every tibia is in 3° of varus so the femoral component is placed in 3° of external rotation relative to the posterior condylar axis to enable a balanced flexion gap. This is not the case as there is wide variability in the bony anatomy and soft tissue envelope of the knee so flexion imbalance may occur. A patient-specific alignment navigated balanced TKA technique was performed whereby the tibia is cut anatomically up to 3° of varus, then a ligament tensor is used to determine the optimal femoral component position for a balanced TKA. This results in variable femoral rotation. The hypothesis is that matching the femoral component rotation to the patient's anatomic tibial cut and soft tissue envelope will not affect clinical outcome METHODS: In a single surgeon series 287 consecutive varus aligned TKA's were performed using this technique with an Attune cruciate retaining fixed bearing TKA with an anatomic patella resurfacing. The angle between the posterior femoral cuts and the posterior condylar axis was collected using Brainlab software. Functional scores were collected prospectively preoperatively and at two years. The variable femoral component rotation was correlated with and compared with the functional outcome scores. RESULTS: The femoral rotation varied from 7° of internal rotation to 8°of external rotation relative to the posterior condylar axis. The mean rotation was 1.1° of external rotation. There was no significant difference in the Oxford score, WOMAC score, Forgotten Knee Score, KOOS Joint Replacement score or Patient Satisfaction in respect to the variable femoral rotation relative to the posterior condylar axis. CONCLUSION: When a more anatomic-balanced TKA technique is used variable femoral rotation will not affect clinical outcome at two years LEVEL OF EVIDENCE: II Prospective Cohort Study.

The crevice sign: a new indicator of meniscal instability in ACL reconstructions.

PURPOSE: Meniscus preservation is key in knee surgery. The newly documented crevice sign indicates instability of the medial meniscus in ACL-deficient knees. Once the sign is visualised, it is imperative that the stability of the medial meniscus is assessed and potentially treated. It was hypothesized that there would be a strong correlation between the presence of an unstable medial meniscal tear in patients with the crevice sign in ACL-deficient knees. METHODS: This was a multicenter prospective study carried out to evaluate the incidence of medial meniscal tears in patients with ACL-deficient knees and their correlation with a crevice sign. All patients (128) who had undergone ACL reconstruction between May 2020 and November 2020 were assessed arthroscopically for meniscal stability and divided in to two groups: stable (n = 84) and unstable (n = 44). Thereafter, the presence of the crevice sign was determined in each case. RESULTS: The populations were comparable in terms of sex and age (Table 1). Fisher's exact test showed a significant association between the presence of the crevice sign and the instability of the medial meniscus (p < 0.001). Descriptive statistics suggest that the presence of crevice sign was associated more frequently to MM instability (38.6% vs 1.2%; p < 0.001). The specificity of this test was 98.8% and its sensitivity was 38.6%. The positive predictive value (PPV) was 94.4% and the negative predictive value (NPV) was 75.5%. Table 1 Descriptions and comparisons of internal meniscus instability of patients by presence of crevice sign Internal meniscus instability (N = 44) Internal meniscus stability (N = 84) Total (N = 128) Gender  N 44 84 128   Male 33 (75.0) 58 (69.0) 91 (71.1)   Female 11 (25.0) 26 (31.0) 37 (28.9) Fisher's exact test (n.s.) Age (years)  N 44 84 128   Mean (ET) 28.6 (9.4) 30.1 (10.2) 29.6 (9.9)   Median (IIQ) 26.5 (22.0;34.5) 27.0 (22.5;37.0) 27.0 (22.0;36.0)   [Min-Max] [14-54] [14-52] [14-54] Wilcoxon test bilateral (n.s.) Crevice sign  N 44 84 128   Absent 27 (61.4) 83 (98.8) 110 (85.9)   Present 17 (38.6) 1 (1.2) 18 (14.1) Fisher's exact test p < 0.001 CONCLUSION: The hypothesis was confirmed since medial meniscal instability was strongly correlated with the existence of the crevice sign and showed high specificity and PPV. LEVEL OF EVIDENCE: III.

Effectiveness of thicker hamstring or patella tendon grafts to reduce graft failure rate in anterior cruciate ligament reconstruction in young patients.

PURPOSE: The purpose of this study was to determine the anterior cruciate ligament reconstruction (ACLR) failure rate in young patients utilizing the New Zealand (NZ) anterior cruciate ligament (ACL) Registry. The hypothesis was that the ACLR rupture rate would be lower for thicker hamstring graft and bone patellar tendon bone (BPB) grafts in comparison to the classic hamstring technique. The ACLR failure rate was assessed according to graft type and patients' sex. METHODS: The NZ ACL registry was utilized to identify all patients aged 20 years or younger at the time of surgery who were skeletally mature and had a minimum 2-year follow-up. Graft ruptures, defined as an ACL revision, were identified according to graft type (traditional 4 strands hamstring semitendinosus and gracilis, 4 strands semitendinosus, 5-6 strands semitendinosus and gracilis, 7-8 strands semitendinosus and gracilis, bone-patella-bone graft). RESULTS: Nine-hundred and ninety-two patients were included. At a mean follow-up of 38 months, 52 cases of graft rupture were recorded, (overall failure rate: 5.2%). The failure rate was not statistically influenced by the graft diameter. Patients with a thinner graft (< 8 mm-196 patients) had a similar failure rate (6%) to patients with a thicker graft (8 mm or more-485 patients) (6.2%). There was a lower failure rate in the BPB group (3.1%) versus all hamstrings group (6%) (ns). Finally, BPB in females had a lower failure rate than all hamstring constructs together (0% versus 5.1%; p = 0.023) CONCLUSION: In a young population traditional four-strand hamstring grafts, multiple strand configurations or BPB ACLR, whatever their size (> or < 8 mm), showed no significant difference in the failure rate in the NZ ACL registry. Female patients who had an ACL reconstruction with BPB graft had a significant lower failure rate than patients who had a hamstring graft. LEVEL OF EVIDENCE: III.

Femoral and tibial bone bruise volume is not correlated with ALL injury or rotational instability in patients with ACL-deficient knee.

PURPOSE: Some researchers have suggested that bone bruises are evidence of rotational instability. The hypothesis was that the extent of lateral bone edema is correlated with the presence of an anterolateral ligament (ALL) injury. The main objective was to determine whether there was a correlation between the presence of an ALL injury the extent of bone bruises. METHODS: A prospective diagnostic study enrolled all the patients who suffered an acute anterior cruciate ligament (ACL) who were operated on within 8 weeks. The extent of bone bruising according to the ICRS classification was measured on preoperative MRIs by two independent blinded raters twice with an interval of 4 weeks. Dynamic ultrasonography (US) to look for ALL injury and the pivot shift test were performed before the ACL surgery. The correlation between ALL injury and bone bruises, and the correlation between an ALL injury and a high-grade pivot shift test were determined. RESULTS: Sixty-one patients were included; 52% of patients had an ALL injury on US. The extent of lateral bone bruise was not related to the presence of an ALL injury, nor related to the presence of a high-grade pivot shift. A grade 2 or 3 pivot shift was significantly correlated with an ALL injury (p < 0.0001). Inter- and intra-rater reliability for the bone bruise rating was excellent. CONCLUSION: The extent of lateral bone bruise is not correlated with ALL injury or a high-grade pivot shift; thus, it is not correlated with rotational instability of the knee. LEVEL OF EVIDENCE: II.

Increased lateral femoral condyle ratio is associated with greater risk of ALC injury in non-contact anterior cruciate ligament injury.

PURPOSE: To examine whether increased lateral femoral condyle ratio (LFCR) correlates with increased risk of Anterior cruciate ligament (ACL) injury (1) and to evaluate the relationship between the LFCR and anterolateral complex (ALC) injury in non-contact ACL torn knees (2). METHODS: Six hundred and seventy-two patients who underwent ACL reconstruction surgery between 2013 and 2019 were retrospectively reviewed, and 120 patients were finally included in the study. Forty patients (ACL + ALC injury) were included in the study group, while forty patients with isolated ACL injury (isolated ACL injury group) and 40 patients who suffered from meniscal tear without ACL or ALC injury were matched in a 1:1 fashion by age, sex, and BMI to the study group (ACL + ALC injury). The LFCR was measured on standard lateral radiographs in a blinded fashion. The differences between the three groups were analyzed by ANOVA. A ROC (Receiver Operating Characteristic) curve was produced to determine risk of ACL injury and risk of concomitant ALC injury in non-contact ACL injury. RESULTS: The mean LFCR was 71.9% ± 3.1% in the ACL + ALC injury group, 68.4% ± 3.2% in the isolated ACL injury group, and 66.8% ± 2.6% in the control group (patients who suffered from meniscal tear without ACL or ALC injury). Significantly greater LFCR was found in the ACL + ALC injury group than that in the isolated ACL injury group (p < 0.017). Greater LFCR was additionally confirmed in the ACL injury group as compared to the control group (p < 0.05). ROC curve analysis demonstrated that LFCR > 68.3% was predictive for an increased risk of ACL injury in the entire cohort. LFCR > 69.4% was predictive for an increased risk of ALC injury in non-contact ACL ruptured patients. CONCLUSION: Increased LFCR was found to be associated with greater risk of ALC injury in non-contact ACL ruptured patients. Additionally, increased LFCR was further confirmed to be correlated with increased risk of ACL injury in an Asian population. The data from this study may help recognize patients undergoing ACL reconstruction that could benefit from additional extra-articular tenodesis. LEVEL OF EVIDENCE: III.

Increased lateral meniscal slope is associated with greater incidence of lateral bone contusions in noncontact ACL injury.

PURPOSE: (1) To investigate whether an increased lateral meniscal slope measured on magnetic resonance image (MRI) would be associated with greater risk of bone contusions in noncontact anterior cruciate ligament injury, and (2) to measure the relationship between the occurrence of bone contusions and associated findings observed in ACL deficient knees such as cartilage damage, anterolateral complex injury and concomitant meniscal tears. METHOD: Patients who underwent ACL reconstruction surgery between 2013 and 2018 were retrospectively reviewed. Sixty-three patients were included in the study group (ACL + bone contusions group), 56 participants were in the control group (isolated ACL group). The presence and severity of bone contusions were determined from preoperative MRIs. The lateral meniscal slope and lateral posterior tibial slope were measured on the MRIs in a blinded fashion. The predictors of lateral bone contusions including age, sex, body mass index, lateral meniscal slope and lateral posterior tibial slope were examined by multivariable logistic regression. Associated findings including concomitant meniscal lesions, intra-articular cartilage damage and anterolateral complex injury, which were also calculated by multivariable logistic regression. RESULTS: The mean lateral meniscal slope in the study group was 6.5° ± 3.5°, which was significantly larger than that in the control group (3.8° ± 2.7°; P < 0.01). In addition, increased lateral meniscal slope was significantly associated with lateral bone contusions in noncontact ACL injury (Lateral femoral condyle (LFC): AOR 16.5; 95% CI 5.40-50.20; P < 0.01; Lateral tibial plateau (LTP): AOR 31.8; 95% CI 8.68-116.7; P < 0.01). However, lateral posterior tibial slope was not significantly associated with bone contusions. Moreover, the presence of lateral bone contusions was associated with concomitant lateral meniscal tears (OR 12.4; 95% CI 3.30-46.30) and cartilage damage (OR 2.9; 95% CI 1.04-8.18). CONCLUSION: An increased lateral meniscal slope was associated with increased risk of lateral bone contusions in noncontact ACL injury. In addition, the presence of lateral bone contusions was associated with intra-articular cartilage damage, anterolateral complex injury and concomitant meniscal tears. Hence, additional information was provided for counseling patients who have increased LMS on the greater risk of knee rotational instability and identify patients undergoing ACL reconstruction who may benefit from extra-articular tenodesis. LEVEL OF EVIDENCE: IV.

The Origin of the Knee Anterolateral Ligament Discovery: A Translation of Segond's Original Work With Commentary.

Paul Segond was a French surgeon who was in practice at the end of the 19th century. A prodigious anatomist, scientist, and surgeon in his day, he is best known for his treatise on the origin of traumatic hemarthrosis of the knee following injury. In this detailed description of the anatomy of the anterolateral aspect of the knee, he describes "a pearly, resistant, fibrous band that is placed under extreme tension when the knee is forcefully rotated internally," which has more recently been described as the anterolateral ligament or a capsular thickening contributing to the anterolateral complex of the knee. His work goes on to speculate about the role of this structure in controlling internal rotation of the knee. The original study was published in French in 1879. Although this work is widely cited, one must question whether many of the citing authors have actually had the opportunity to read it. As such, we sought to unlock this treasure by translating the original study into English and exposing this illuminating, forward-thinking and historical tour de force to the broader orthopaedic community.

Determination of normal KOOS and WOMAC values in a healthy population.

PURPOSE: The KOOS questionnaire is used to assess the symptoms and function of patients with traumatic or degenerative knee pathology. The WOMAC score has been validated mainly in the context of knee osteoarthritis. The distribution of these scores in a non-diseased population is not known. The hypothesis was that KOOS and WOMAC scores were influenced by patients' age, sex, and BMI. The primary objective of this study was to describe, for the first time, the distribution of KOOS and WOMAC scores in a healthy population based on age, sex, and BMI. METHODS: This was a pilot (innovative), cross-sectional, international, multicenter, descriptive study. Persons accompanying patients to our clinic were invited to participate in this study by filling out the KOOS questionnaire. These data were also used to calculate the WOMAC score. The study was designed according to guidelines on pilot studies and planned to enroll a minimum of 30 subjects in each age, gender, and BMI group. Expected KOOS and WOMAC scores by age, gender, and BMI were determined using a linear regression model. RESULTS: Seven hundred and fourteen subjects were included: 305 men (42.7%) and 409 women (57.3%). For the KOOS score, as age increases, there was a decrease in the "ADL" (p = 0.0001) and "sport" (p = 0.0001) items and an increase in the "symptoms" (p = 0.0025) and "QOL" items (p = 0.0001). Women had lower scores (p < 0.05) than men on all the KOOS items, except "QOL". For the WOMAC, the "pain", "stiffness", and "function" items varied significantly based on age (p = 0.0203) and sex (p = 0.0121). The "stiffness" item varied significantly based on age (p = 0.0005) and sex (p = 0.0477). The "function" item varied significantly based on age (p = 0.0001) and sex (p = 0.0256). The expected value for the KOOS and WOMAC scores in a healthy population without any knee ailments were determined. CONCLUSIONS: The KOOS and WOMAC scores vary significantly based on age, sex, and BMI in a healthy population. This study also provides KOOS and WOMAC values in a population without any knee issue. These scores can be used, in a daily practice, as a reference to assess functional outcomes after a surgical procedure. LEVEL OF EVIDENCE: IV.

Prospective comparative study of knee laxity with four different methods in anterior cruciate ligament tears.

BACKGROUND AND PURPOSE: Anterior knee laxity can be evaluated using different devices, the most commonly used being the Telos®, KT1000®, Rolimeter®, and GNRB®. However, the laxity values obtained with these devices have never been compared to one another. As such, the outcomes of studies using these different knee laxity measurement devices may not be comparable. The primary purpose of this study was to determine the side-to-side laxity difference in patients with one ACL-injured knee, using each of these devices, and to compare the values obtained from each. We hypothesized that the measurements of laxity would vary depending on the device used. METHODS: This was a prospective study. All patients with an ACL injury, in which surgical reconstruction was planned, underwent pre-operative knee laxity measurements using four different devices. The concordance correlation coefficient (CCC) of the results was compared between the four devices. RESULTS: The study enrolled 52 patients. With regard to the values of the side-to-side differences, the KT1000® and the GNRB® obtained the most similar values (CCC = 0.51, 95% CI 0.37-0.63). The two devices with the lowest correlation were the Telos® and the Rolimeter® (CCC = 0.04, 95% CI - 0.14-0.23). The comparability was considered average for the KT1000® and GNRB® and poor for the other devices. CONCLUSIONS: The knee laxity devices used in regular practice are not comparable to one another. As a result, caution must be taken when comparing results from studies using these different devices.

Ultrasonographic Evaluation of Anterolateral Ligament Injuries: Correlation With Magnetic Resonance Imaging and Pivot-Shift Testing.

PURPOSE: (1) To compare the diagnostic ability of ultrasonography (US) and magnetic resonance imaging (MRI) to detect anterolateral ligament (ALL) injuries in anterior cruciate ligament (ACL)-deficient patients, and (2) to evaluate the correlation between ALL injury status (as determined by US and MRI) and the knee's rotational stability. METHODS: Thirty patients with an isolated ACL injury were included prospectively over a 3-month period. The condition of the ALL was evaluated by 2 experienced radiologists using both US and MRI. Rotational stability was evaluated by 2 surgeons with the pivot-shift test with patients under general anesthesia. It was classified as either negative (grades 0 and I) or positive (grades II and III). The radiologists were blinded to the knee's rotational stability, and the surgeons were blinded to the ALL's status based on the US images. The correlation between the ALL's injury status (US and MRI) and the pivot shift was determined with the Pearson χ2 test. To evaluate the reproducibility of the results, the agreement between observers was determined with the Cohen κ coefficient. RESULTS: On US, the ALL was identified and visible over its entire length in 100% of patients (30 of 30, κ = 1). The ALL was injured in 63% of patients (19 of 30, κ = 0.93). On MRI, the ALL was identified in 96% of patients (29 of 30, κ = 0.91). The ALL appeared injured in 53% of cases (16 of 30, κ = 0.93). An ALL that appeared injured on US was more often associated with a positive pivot shift than was an uninjured ALL (75% vs 39%, χ2 = 13.7, P < .05). The interobserver agreement was high for both US (κ = 0.91-1) and MRI (κ = 0.76-1). CONCLUSIONS: US is a reproducible examination for the diagnosis of ALL injury. An ALL injury is most often associated with a high pivot-shift grade. LEVEL OF EVIDENCE: Level II, prospective comparative study.

Cryotherapy With Dynamic Intermittent Compression Improves Recovery From Revision Total Knee Arthroplasty.

BACKGROUND: The goal of this study was to assess the efficacy of cryotherapy with dynamic intermittent compression (CDIC) in relieving postoperative pain, decreasing blood loss, and improving functional scores after revision total knee arthroplasty (rTKA). METHODS: We conducted a prospective case-control study (level of evidence: I) to evaluate the efficacy of CDIC on postoperative bleeding, pain, and functional outcomes after rTKA. Forty-three cases were included at a single institution and divided in 2 groups: a control group without CDIC (n = 19) and an experimental group with CDIC (n = 24). Bleeding was evaluated by calculating total blood loss, pain at rest was evaluated with a visual analog scale on postoperative day 3, and function was assessed using the Oxford score at 6 months postoperatively. The comparative analysis was performed using the Fisher exact test. RESULTS: The CDIC group had significantly lower total blood loss (260 vs 465 mL; P < .05), significantly less pain on day 3 (1 vs 3; P < .05), and a significantly higher functional score (42 vs 40; P < .05) than the control group. CONCLUSION: This is the first report dealing with the use of CDIC after rTKA. According to our results, it improves the recovery of patients who underwent rTKA; thus, it should be integrated into our daily practice.

Cadaveric Study Comparing the Biomechanical Properties of Grafts Used for Knee Anterolateral Ligament Reconstruction.

PURPOSE: To measure the biomechanical properties (maximum load, stiffness, and elongation) of the anterolateral ligament (ALL), gracilis, and iliotibial band (ITB) within the same subject. METHODS: Thirteen unpaired knees were used (7 women, 6 men). The donors had a mean age at death of 54 years (range: 37 to 70 years). The mechanical properties of two types of ALL grafts were evaluated: ITB and two-strand gracilis. The mechanical properties of ALL were also measured. Validated methods were used to perform the tensile tests to failure and to record the results. Student's t-test was used to compare the various samples. RESULTS: The maximum load to failure was 141 N (±40.6) for the ALL, 200.7 N (±48.7) for the gracilis, and 161.1 N (±27.1) for the ITB. Only the gracilis had a significantly higher failure load than ITB and ALL (P = .001 and P = .03). The stiffness was 21 N mm-1 (±8.2) for the ALL, 131.7 N mm-1 (±43.7) for the gracilis, and 39.9 N mm-1 (±6) for the ITB. The elongation at failure was 6.2 mm (±3.2) for the ALL, 19.9 mm (±6.5) for the gracilis, and 20.8 mm (±14.7) for the ITB. CONCLUSIONS: The gracilis had the highest maximum load to failure. The ITB's mechanical properties most closely resemble those of the ALL. CLINICAL RELEVANCE: The biomechanical properties of each potential ALL graft can be factored in when deciding which type of graft to use.

Ultrasonographic Identification of the Anterolateral Ligament of the Knee.

PURPOSE: To determine ultrasonography's sensitivity for identifying the anterolateral ligament (ALL). METHODS: A descriptive study of 18 cadaveric knees was performed. Ultrasonography was used to locate any anterolateral structures at the knee that could correspond to the ALL. The structure's length and relation with other notable anatomic landmarks (fibular head, Gerdy tubercle, joint line, lateral femoral epicondyle, popliteus tendon insertion) were quantified. The ultrasonography measurements were validated by dissecting each knee. The sensitivity of ultrasonography for detecting the ALL and the agreement between the ultrasonographic and cadaveric measurements (Cohen κ) were determined by statistical analysis. RESULTS: The ALL was found in all 18 cadaveric knees and corresponded anatomically to the ultrasonographic descriptions. Ultrasonography had 100% sensitivity for detecting the presence of the ALL. The ALL's insertion on the lateral femoral condyle was, on average, 12.08 mm (SD, 4 mm; range, 7 to 15 mm) proximal and posterior to the lateral femoral epicondyle and 20.5 mm (SD, 3 mm; range, 16 to 24 mm) proximal to the middle of the popliteus tendon insertion. The ALL inserted onto the tibia, midway between the Gerdy tubercle and the fibular head; the distance between the midpoint of the tibial insertion and middle of the Gerdy tubercle was 19.05 mm (SD, 2.1 mm; range, 15 to 25 mm), and the distance was 19.13 mm (SD, 2.3 mm; range, 14 to 23 mm) to the tip of the fibular head. The agreement between the ultrasonographic and cadaveric findings was excellent (Cohen κ coefficient between 0.88 and 0.94). CONCLUSIONS: Ultrasound imaging is a suitable tool for identifying the ALL of the knee, and it allowed for a detailed analysis of the entire ALL in all 18 knees. However, its ability to evaluate any injuries to the ALL must still be shown. CLINICAL RELEVANCE: Ultrasonography can be used to confirm the integrity of the ALL.

Posterior C1-C2 Fixation Using Absorbable Suture for Type II Odontoid Fracture in 2-Year-Old Child: Description of a New Technique and Literature Review.

Odontoid synchondrosis fractures are rare in children, even though they are the more common cervical fracture in children less than 7 years old. Nonoperative treatment with external orthosis immobilization is the treatment of choice for stable undisplaced or minimally displaced injuries. In unstable fractures, when reduction cannot be achieved or maintained, surgical fixation is recommended. We report a 2-year-old boy with an unstable fracture of the odontoid treated surgically using an absorbable monofilament suture for C1-C2 interlaminar fixation without bone grafting. This suture was strong enough to provide the stability necessary to allow healing of the synchondrosis and the delayed resorption of the suture was followed by complete restoration of the mobility between C1 and C2. This case illustrates that surgical stabilization using an absorbable suture in young children with an unstable odontoid fracture is a safe and effective alternative to other surgical techniques. LEVEL OF EVIDENCE: Level III.

Modified head-neck offset for diagnosing anterior femoro-acetabular impingement.

PURPOSE: The head-neck offset described by Eijer et al. (eHNO), which is used to diagnose anterior femoro-acetabular impingement (FAI), can be difficult to measure. The aim of this study was to verify if a modified head-neck offset (mHNO) provides more accurate and reproducible values than those of the eHNO. METHODS: The eHNO, mHNO, cephalic radius and alpha angle were measured on frog-leg radiographs of a group of patients with FAI and a control group (T); three independent reviewers measured the 50 hips in each group twice. The comparison of the two HNOs focused on reproducibility (intraclass correlation coefficient), validity (correlation with alpha angle), practical utility (difference between means in the FAI and control groups) and accuracy of the diagnostic thresholds. RESULTS: The mHNO had better reproducibility (p < 0.05) within and between observers in all study subjects than that of the eHNO (0.938 and 0.979 vs 0.881 and 0.904). The correlation with the alpha angle was also better (p < 0.05) for the mHNO than that for the eHNO. The diagnostic performances of the mHNO and mAOR thresholds were higher than those of the eHNO, eAOR and alpha angle. CONCLUSIONS: The new HNO is easier to measure, more reproducible and more accurate. A modified HNO <5 mm and a modified AOR <0.100 on the frog-leg view argued in favour of a pathological cam-type head-neck junction.

Triple osteotomy of the pelvis for Legg-Calve-Perthes disease: a mean fifteen year follow-up.

PURPOSE: This study presents the results of a prospective consecutive cohort of patients with Legg-Calvé-Perthes disease (LCPD) operated with triple osteotomy of the pelvis (TOP) between 1989 and 2005. We attempted to determine whether the results of TOP remain stable with time and consequently lower the risk of subsequent osteoarthritis. The primary study aims were to determine the maintenance of head coverage and joint congruity, and functional outcomes of this surgery. METHODS: Forty-five patients with a mean follow-up of 15.2 years (range eight to 24) were included. RESULTS: At latest follow-up, two patients were lost to follow-up, and two required a surgical reoperation. Cumulative maintenance of head coverage and joint congruity rate for all TOP was 84.6 % (95 % CI: 82.3-90.6 %) at 15 years. Factors significantly associated with poor long-term results were the age at diagnosis and Greene index. CONCLUSION: TOP in LCPD provides satisfactory and reproducible long-term clinical results.

Can the gracilis replace the anterior cruciate ligament in the knee? A biomechanical study.

PURPOSE: The purpose of this study was to determine whether a four-strand gracilis-only construct possesses the biomechanical properties needed to act as an anterior cruciate ligament (ACL) reconstruction graft. METHODS: This was a pilot study with 32 cadaver specimens. The biomechanical properties of three types of grafts were determined using validated tensile testing methods: patellar tendon (BTB), both hamstring tendons together (GST4) and gracilis alone (G4). RESULTS: The maximum load at failure of the G4 was 416.4 N (±187.7). The GST4 and BTB had a maximum load at failure of 473.5 N (±176.9) and 413.3 N (±120.4), respectively. The three groups had similar mean maximum load and stiffness values. The patellar tendon had significantly less elongation at failure than the other two graft types. CONCLUSIONS: The biomechanical properties of a four-strand gracilis construct are comparable to the ones of standard grafts. This type of graft would be useful in the reconstruction of the anteromedial bundle in patients with partial ACL ruptures.