Distribution of nerve endings in human thumb interphalangeal joint.

This study aims to quantitatively analyze the distribution of encapsulated nerve endings in the human thumb interphalangeal (IP) joint capsule. There are three types of nerve endings. Type-I nerve endings (Ruffini-like ending) sense pressure changes, Type II (Pacini-like ending) nerve endings contribute to the kinesthetic sense, and Type III (Golgi-like ending) nerve ending provides proprioceptive information. We dissected five right thumbs IP joints from freshly frozen cadavers (5 men). The mean age of the cadavers at the time of death was 63.4 years (55-73). Sections were stained with the hematoxylin-eosin and antiprotein gene product 9.5 (PGP9.5) to identify encapsulated nerve endings. Transverse sections were cut and divided into volar, dorsal, and then into two equal parts, proximal and distal. The density of encapsulated nerve endings compared to volar versus dorsal and proximal versus distal regions was examined. This study showed that type 1 nerve endings were more common in the distal parts of the IP joint (p < 0.05). Also, type 3 nerve endings were observed in the thumb IP joint. There was no difference between regions in type II and type III nerve endings. The current study demonstrates that the distribution of encapsulated nerve endings in the IP joint is different from the PIP and DIP joints. Moreover, further studies are required to understand the thumb's physiology.

Risk factors associated with breakage of tibio-fibular syndesmotic screws.

PURPOSE: This retrospective study aimed to investigate the factors associated with the breakage of tibio-fibular syndesmotic screws (SS). METHODS: 69 patients with unstable AO-Weber Type 44-B ankle fractures who underwent three cortex SS (3.5 mm ø) fixation were included. Patients were followed for at least one year (mean, 18.3 ± 7.6 months). At the final follow-up, patients with broken (Group I) and intact (Group II) SS were compared regarding age, gender, height, weight, body mass index, fracture type, SS length, location, and orientation. Multivariate logistic regression was used to identify the independent risk factors associated with SS breakage. The sensitivity, specificity, cut-off value, and area under the ROC curve were analyzed. RESULTS: A stepwise backward logistic regression analysis revealed that age was the only independent predictor for SS breakage (OR = 0.938, 95% CI = 0.904-0.973, R2 = 0.270). ROC curve analysis demonstrated that patients younger than 36 years were associated with seven times increased risk of SS breakage [Odds ratio (95% CI), 7.042 (2.251-22.031)]. CONCLUSION: Age under 36 years was the only significant risk factor for SS breakage. The higher incidence of breakage of the syndesmotic screw can be informed to patients younger than 36.

Single versus double plate fixation of humeral shaft nonunion.

INTRODUCTION: Humeral shaft fractures are common fractures of the diaphysis of the humerus. The aim of this study was to evaluate factors affecting the clinical outcomes of humeral nonunions surgically treated with open reduction and single- versus double-plate fixation with grafting. MATERIALS AND METHODS: A total of 31 patients with nonunion treated with single- or double-plate screw fixation with bone grafting were retrospectively analysed. The patients were divided into two groups according to the treatment method as Group 1 (single-plate, n = 14) and Group 2 (double-plate, n = 17). Data including demographic and clinical characteristics of the patients, initial and final treatment, type of nonunion and localisation, graft use, shortening, follow-up, time to union, Quick Disabilities of the Arm, Shoulder and Hand (Quick-DASH) scores, and patient-reported cosmetic outcomes were recorded. RESULTS: Of the patients, eight were males, and 23 were females, with a mean age of 47.6 ± 15.8 (range, 20-86) years. Initial treatment was conservative treatment (Sarmiento brace) in seven patients, plate fixation in 22 patients, and intramedullary nailing in two patients. The mean follow-up was 31.0 ± 16.9 months in Group 1 and 25.4 ± 15.6 months in Group 2. There was one nonunion in Group 1 and three in Group 2. There were no significant differences in the union rate and time to union (p = 0.378 and p = 0.262, respectively). The mean Quick-DASH scores and cosmetic results were similar between the groups (p = 0.423 and p = 0.165, respectively). Radial nerve palsy developed in three patients in Group 2, and all these patients recovered completely during follow-up. CONCLUSIONS: Although the double-plate fixation technique has similar clinical, radiological, and functional results to single-plate fixation, it is a more invasive and expensive technique with a longer operation time. Therefore, it should not be used as the first-line treatment option for all humeral shaft nonunion. Nevertheless, the double-plate technique may be preferred to achieve in cases requiring high stability, such as hypertrophic nonunion, osteopenia and comminuted fractures.

Variations of cross-sectional meniscal morphology between similar-sized menisci: implications on donor selection for meniscal allograft transplantation.

PURPOSE: This study aimed to investigate the morphological variations in the cross-sectional anatomy of the meniscus between similar-sized matched menisci. MATERIALS AND METHODS: Knee MRI of 329 patients with intact menisci were retrospectively reviewed, and the meniscal length (ML), meniscal width (MW), and cross-sectional dimensions (meniscal height and width) of the anterior, posterior horns, and the corpus were measured. Patients with similar-sized menisci who had less than 1 mm difference in ML and MW were matched. 330 male-to-male medial menisci (MM), 623 male-to-male lateral menisci (LM), 82 female-to-female MM, 233 female-to-female LM, 176 cross-gender MM, and 265 cross-gender LM unique combination of ideally matched pairs (total: 1709) were generated. The disparity in the cross-sectional dimensions, absolute difference, and the paired percent differences was statistically analyzed. RESULTS: The ML and MW in all groups were statistically similar, with a predefined absolute difference of 1 mm both for ML and MW (paired percent difference < 5%). The cross-sectional segmental meniscal dimensions were similar within all groups, but the paired percent differences showed high variations between a mean of 12.1-21.5% and up to 150.9%. The paired percent difference of MM in each segmental dimension was similar among different gender combinations. However, segmental paired percent differences of LM showed statistical differences in anterior horn width (AHW) (p: 0.001) and posterior horn width (PHW) (p: 0.001). In subgroup comparisons, the paired percent difference of AHW was higher in the female-to-female group compared to cross-gender (p: 0.023) and male-to-male groups (p: 0.001). The paired percent difference of PHW was smaller in the male-to-male group compared to female-to-female and cross-gender groups (p: 0.001 for both). CONCLUSIONS: Segmental cross-sectional anatomy showed wide variations despite strict matching in ML and MW. These variations were present in all gender combinations. The meniscal 3D shape is unique, but acceptable limits of similarity need further research. LEVEL OF EVIDENCE: Retrospective study, Level III.

The relationship between quadriceps fat pad syndrome and patellofemoral morphology: a case-control study.

BACKGROUND: The purpose of this prospective case-control study is to investigate the relationship between quadriceps fat pad syndrome (QFPS) and patellofemoral morphology. MATERIALS AND METHODS: Twenty-two patients with QFPS and 22 age- and gender-matched healthy volunteers were included. The diagnosis of QFPS was supported both clinically and radiologically. On magnetic resonance imaging (MRI), patellofemoral morphology was evaluated with 13 radiological measurements including trochlear sulcus angle, trochlear sulcus depth, trochlear facet asymmetry, trochlear condyle asymmetry, lateral trochlear inclination angle, patellar translation, tibial tubercle-trochlear groove (TT-TG) distance, Insall-Salvati ratio, patellotrochlear index, patellar tilt, the ratio between lateral and medial facet lengths, interfacet angle, and quadriceps tendon thickness. The mean of measurements was compared between groups using the Mann-Whitney U test. RESULTS: There were 22 patients (12 male, 10 female) with mean age of 30.81 ± 1.41 (range 19-38) years in group I and 22 patients (12 male, 10 female) with mean age of 31.13 ± 1.31 (range 19-39) years in group II. The mean age and the gender distribution were statistically similar between groups (p = 0.845, p = 1, respectively). All measured values except for patellar tilt (p = 0.038) and TT-TG distance (p = 0.004) were similar (p > 0.05 for the other variables). However, all of the measured variables were within the normal range. CONCLUSIONS: QFPS may not be associated with anatomical variations of the patellofemoral joint. Further studies are required to understand the etiology and risk factors. LEVEL OF EVIDENCE: Level III, prospective case-control study.

Comparison of magnesium versus titanium screw fixation for biplane chevron medial malleolar osteotomy in the treatment of osteochondral lesions of the talus.

PURPOSE: This retrospective study aimed to compare the clinical and radiological outcomes of patients who underwent biplane chevron medial malleolar osteotomy (MMO) for osteochondral lesions of the talus (OLT), fixed with either magnesium (Mg) or titanium (Ti) screws. METHODS: A total of 22 patients (12 male and 10 female) with a mean age of 40.6 ± 12.5 years (range 18-56 years) who underwent MMO for OLT treatment were included in this retrospective study. Of the 22 patients, MMO was fixed with bioabsorbable Mg screws (Alloy: MgYREZr) in 11 patients, and in the remaining 11 patients (one bilateral) MMO was fixed with Ti screws. All patients were followed up for at least 1 year with a mean of 20.7 ± 8.9 months (range 12-49 months). The American Orthopedic Foot and Ankle Society (AOFAS) scale and the visual analog scale (VAS) were used to evaluate the clinical results. Union of the osteotomy, postoperative displacement and all other complications were followed and analyzed. RESULTS: An improvement in the AOFAS scale and VAS points were recorded in both groups with no statistically significant difference between the groups (p 0.079 and 0.107, respectively). Complete union of the osteotomy was obtained in all patients. One patient in the Ti group required implant removal due to pain and irritation. There were no other significant complications in either group. CONCLUSIONS: The results of this study showed that bioabsorbable Mg compression screws have similar therapeutic efficacy to Ti screws in respect of functional and radiological outcomes in MMO fixation. Bioabsorbable Mg screw is an alternative fixation material which can be safely used for MMO in ankle surgery. LEVEL OF EVIDENCE: Level IV, retrospective case series.

Bioabsorbable magnesium screw versus conventional titanium screw fixation for medial malleolar fractures.

BACKGROUND: It is still unknown whether bioabsorbable magnesium (Mg) screws provide an advantage over titanium screws in the treatment of medial malleolar (MM) fractures. The purpose of this retrospective study is to compare the clinical and radiological outcomes of MM fractures fixed with either bioabsorbable Mg screws or conventional titanium screws. MATERIALS AND METHODS: A cohort of 48 patients with MM fractures who underwent compression screw fixation was retrospectively reviewed. Twenty-three patients (16 male, 7 female; mean age: 37.9 ± 17.7 years) were treated with bioabsorbable Mg screws, and 25 patients (14 male, 11 female; mean age: 45.0 ± 15.7 years) were treated with conventional titanium screw fixation. All patients were followed up for at least 1 year, with a mean time of 24.6 ± 10.5 months (12-53 months). The American Orthopedic Foot and Ankle Society (AOFAS) scale was used to evaluate the clinical results. The Kellgren-Lawrence (KL) osteoarthritis grading was used to evaluate posttraumatic osteoarthritis on final ankle radiographs. Fracture union, rate of implant removal, and complications were recorded. Comparative analysis of two independent groups was performed using the chi-squared test and the Mann-Whitney U-test. RESULTS: The two groups were comparable concerning demographic and clinical characteristics. Age (p = 0.146), sex (p = 0.252), side (p = 0.190), MM fracture type (p = 0.500), associated fractures (p = 0.470), and follow-up period (p = 0.903) were similar between the groups. At final follow-up examination, AOFAS score (p = 0.191) was similar between groups. Fracture union was achieved in all cases. Grade of posttraumatic osteoarthritis, according to KL, was equally distributed in both groups (p = 0.074). No deep infection or osteomyelitis was seen. Five patients in the titanium screw group underwent implant removal, due to pain in three of them and difficulty in wearing shoes in the other two (p = 0.031). Implant removal was performed after a mean of 14.2 ± 3.1 months (12-19 months). CONCLUSIONS: Bioabsorbable Mg and titanium screws had similar therapeutic efficacy in MM fracture fixation regarding functional and radiological outcomes. However, the rate of implant removal was higher with titanium screws. Bioabsorbable Mg screws may be a favorable fixation option since secondary implant removal procedures can be prevented. LEVEL OF EVIDENCE: Level IV, Retrospective case series.

Symptomatic os talus secundarius: a case report and review of the literature.

Os talus secundarius is an extremely rare accessory ossicle located at the lateral aspect of the talus just anterior to the fibula. Although rarely seen, it may cause lateral-sided chronic ankle pain. Only a few cases of symptomatic os talus secundarius have been reported to date. Herein, a 42-year-old male patient with symptomatic os talus secundarius is presented, and its imaging findings, differential diagnosis, and treatment are discussed. LEVEL OF EVIDENCE: Level IV.

Fixation of medial malleolar fractures with magnesium bioabsorbable headless compression screws: short-term clinical and radiological outcomes in eleven patients.

OBJECTIVE: The purpose of this retrospective study was to evaluate the outcome of medial malleolar fractures treated with magnesium (MgYREZr) bioabsorbable compression screw fixation. MATERIALS AND METHODS: Eleven patients with a medial malleolar fracture (either isolated or accompanied by bimalleolar or trimalleolar ankle fractures) who were treated with magnesium bioabsorbable compression screws between 2015 and 2016 in our hospital were retrospectively evaluated. Patients were monitored with a mean follow-up of 17.3 ± 4.1 months (range 12-24 months). The mechanism of injury was ground level falls in all patients. All fractures were classified as closed fractures. American Orthopedic Foot and Ankle Society's (AOFAS) scale and the visual analog scale (VAS) were used to evaluate the clinical results during the final follow-up. Bone union and a possible loss of reduction were assessed with serial radiographs. Potential complications including revision surgery and infection were recorded and reported. RESULTS: There were 11 patients (4 female, 7 male) with a mean age of 41 ± 21.9 years (range 20-78 years). Six patients had Herscovici type C and five patients had type B fractures. At the final follow-up the mean AOFAS score was 94.9 ± 5.7 points (range 85-100 points) and the mean VAS score was 0.4 ± 1.2 points (range 0-4 points). Radiographic solid union was achieved in all cases. No complications were seen during the follow-up. No patients required implant removal or revision surgery. CONCLUSIONS: This is the first study that investigates the use of bioabsorbable magnesium compression screws in medial malleolar fractures. The results of this study revealed that fixation of medial malleolar fractures with bioabsorbable magnesium compression screws provides adequate fixation with good functional results. LEVEL OF EVIDENCE: Level IV, therapeutic, retrospective case series.

Posterior tibial tendon impingement due to os subtibiale: a case report and up-to-date review.

Os subtibiale is a rare accessory ossicle located at the tip of the medial malleolus. Although this small ossicle usually has no clinical significance, in some cases it may be a source of ankle pain. Symptomatic os subtibiale is an extremely rare diagnosis, and few cases have been reported to date. The case presented is of a 35-year-old female patient with symptomatic os subtibiale, with a discussion of the diagnosis, clinical findings, and treatment options.

Quantitative Scheimpflug camera study of the lens density in healthy Turkish population.

The purpose of this study is to evaluate the association between the age and the density of anterior, posterior, and nuclear parts of lens and detect the normal lens density (LD) values in different age groups. 370 eyes of 370 voluntary healthy Turkish subjects were included. These were divided in four groups according to their age. These were Group 1 (51-65 years), Group 2 (41-50 years), Group 3 (31-40 years) and Group 4 (20-30 years). LD values of anterior, nuclear, posterior, and total (average) were measured using Pentacam HR Scheimpflug camera system. Both eyes of each subject were scanned twice in automatic release and 50-picture 3-dimensional (3D) scan modes by one experienced observer. 207 of the participants were females and 163 were males, with a mean age of 40.57 ± 13.06 years. The differences between groups in terms of nuclear area, posterior area, and average LD measurements were significant but anterior area was not. The nuclear area and average LD had high positive correlation with age (r = 0.72, p < 0.001, r = 0.63, p < 0.001, respectively); posterior area LD had a weak negative correlation with age (r = -0.16, p = 0.001). The mean LD values between female and male subjects showed no significant difference. The anterior region of the lens has the highest and nuclear area has the lowest value of LD in young people. In older people, the anterior area did not show a significant change, nuclear and total areas showed a significant increase but posterior area showed a significant decrease.

Evaluation of the long-term results of trabectome surgery.

The aim of this study was to investigate the safety and efficacy of ab interno trabeculectomy which is a minimally invasive glaucoma surgery, in the late period, performed via trabectome instrument. A total of 70 eyes followed up with a diagnosis of open-angle glaucoma (OAG) and undertaken trabectome surgery were included in the study. Preoperative and postoperative intraocular pressures (IOPs), number of the drugs used, and complications were retrospectively investigated and the data were evaluated. The criteria of success were accepted as an IOP value ≤21 mmHg or ≥30 % reduction in IOP and no need for a second operation. Mean IOP was decreased by 38 % from a preoperative value of 28.77 ± 5.34 to 17.62 ± 2.81 mmHg at the end of 18 months. Likewise, mean drug usage was decreased by 48 % from a preoperative value of 3.3 ± 1.01 to 1.7 ± 1.16 at the end of 18 months. Both decreases were statistically significant (p < 0.05). Postoperative success rates were 82.8 % in the 6th month, 81.4 % in the 9th month, 77.1 % in the 12th month, and 70 % in the 18th month. Most common complication observed was intraoperative reflux hemorrhage and no serious complication was observed. Trabectome surgery is an effective and safe method in early-stage open-angle glaucoma types that cannot be controlled despite maximal medical therapy. This procedure is a proper surgical option in patients targeted for moderate IOP without the need for a topical medication or with less drug usage.

Postoperative changes in olfactory function after transcanalicular diode laser dacryocystorhinostomy.

PURPOSE: Transcanalicular diode laser dacryocystorhinostomy (TCL-DCR) is used much in recent years for the surgery of nasolacrimal duct obstruction (NLDO). Although TCL-DCR is accepted to be minimally invasive, safe, and effective, there is no report focusing on postoperative changes in olfactory function after this procedure. Hence, the aim of this current study was to investigate the changes in olfactory function after TCL-DCR procedure. MATERIALS AND METHODS: This study was carried out in 42 volunteers (16 men and 26 women) between the ages of 20 and 81 years. All participants received detailed lateralized olfactory tests preoperatively and at the postoperative first week, first month, third month, and sixth month. After lateralized olfactory tests were performed, the results were grouped according to the side of the nasal passage where the operation was performed for NLDO: the nonoperated side served as the control. RESULTS: The current investigation produced 2 major findings: (1) olfactory function decreased significantly after TCL-DCR procedure at the operated side of the nose compared with the nonoperated side; (2) olfactory abilities of the patients returned to normal within 3 months. CONCLUSION: The results of this study showed that transcanalicular diode laser could be used safely in terms of olfactory function for dacryocystorhinostomy. Temporary decrease of olfactory function on the side having TCL-DCR should be taken into account when obtaining informed patient consent.

Comparison of patient positions without traction table for proximal femoral nailing: Supine, semilithotomy and lateral decubitus positions.

BACKGROUND: Femur intertrochanteric fractures are performed commonly in a supine position with a traction table. There is a challenge in obtaining traction tables, especially in low- and middle-income countries. However, there is still a debate on which position should be preferred if the traction table cannot be obtained. METHODS: A total of 123 patients who were treated for femur intertrochanteric fracture (AO/OTA A1 or A2) using cephalomedullary nail (CN) were retrospectively analyzed. All three positions without traction table (supine:25 patients, semilithotomy:36 patients and lateral decubitus:62 patients) were compared according to preparation time, surgical time, Tip-Apex distance (TAD), zones of lag screw placement, collodiaphyseal angle (CDA), CDA difference (∆ CDA), postoperative posterior sag, medial cortical support and Baumgardner reduction quality criteria. RESULTS: The preparation time was longer in the semilithotomy group, and surgery time was longer in the supine position group. There was no difference according to total time, surgical time, TAD, CDA difference (∆ CDA), postoperative posterior sag, medial cortical support and Baumgardner reduction quality criteria. Target lag screw placement is superior in supine and semilithotomy group than lateral decubitus. CONCLUSION: This study concluded that there was a difference in preparation time, surgery time and optimal lag screw placement in the lateral plane between groups. The surgeon may prefer all three methods according to patient benefit and surgeon familiarity.

Relationship between ganglion cell complex thickness and vision in age-related macular degeneration treated with aflibercept.

PURPOSE: This study aimed to analyze the correlation between ganglion cell complex thickness (GCCT) and vision compared with the choroidal thickness (CT) and central retinal thickness (CRT) in relation to the outcomes of intravitreal aflibercept treatment for choroidal neovascular membranes secondary to age-related macular degeneration (AMD). METHODS: This was a prospective, observational study. Forty-three eyes of 38 patients with wet AMD received a monthly loading dose of 2 mg aflibercept by intravitreal injection (IVI) during the first 3 months and were then followed at regular monthly intervals for an average of 10 months by a pro re nata regimen. All patients were examined using spectral domain-optic coherence tomography (OCT) and enhanced depth imaging OCT. According to their response to IVI treatment in the third month, patients were divided into 2 groups, both functionally and anatomically. RESULTS: Three-month GCCT and optic disc retinal nerve fiber layer thickness (ODRNFLT) had the most correlation with the 10-month vision (p = 0.002, p = 0.02, respectively). While baseline GCCT was most correlated with the functional response, baseline CRT was most correlated with the anatomical response (p = 0.01, p = 0.004, respectively). CONCLUSIONS: The results suggest that a reduction in 3-month GCCT indicates a good long-term vision outcome, while a reduction in 3-month ODRNFLT shows a poor long-term vision outcome. The literature suggests that this study is the first to demonstrate that baseline GCCT is more strongly correlated with the functional response than it is with CT and CRT. Hence, GCCT has a prognostic value for vision impairment.

Influence of hyperbaric oxygen therapy on central corneal thickness.

BACKGROUND/AIMS: Hyperbaric oxygen (HBO) therapy is used in the treatment of several disorders. Little is known about the effects of HBO treatment on corneal thickness. The aim of this study was to investigate the effect of HBO treatment on central corneal thickness. METHODS: Thirty-two subjects (18 males and 14 females, mean age 57.3 ± 16.7 years) undergoing HBO treatment were consecutively enrolled. The subjects were assigned into diabetic (n = 16) and nondiabetic groups (n = 16). Best-corrected visual acuity was recorded before HBO treatment, and anterior and posterior segment examinations were performed on a slit lamp biomicrosope. Central corneal thickness was measured with an ultrasonic pachymeter before and immediately after HBO treatment, which lasted 120 min at 2.4 atmospheres absolute with three 30-min oxygen and two 5-min air breathing periods. RESULTS: HBO treatment did not change the central corneal thickness in diabetic subjects (547.6 ± 34.5 vs. 548.6 ± 34.6 µm; p = 0.606). In nondiabetic subjects, however, the central corneal thickness was significantly reduced after HBO treatment (576.5 ± 34.8 vs. 569.0 ± 34.8 µm; p < 0.001). CONCLUSION: A single exposure to HBO treatment reduced the central corneal thickness in nondiabetic subjects but not in diabetic subjects. However, the change in central corneal thickness was minor.

Bioabsorbable magnesium screw fixation for tibial tubercle osteotomy; a preliminary study.

BACKGROUND AND AIM: Metallic screws are commonly used to fix tibial tubercle osteotomies (TTO). However, hardware removal late after osteotomy union is one of the most common causes of reoperation following TTOs. The use of bioabsorbable screws may eliminate secondary surgeries, but there is no study on their use in this indication. The purpose of this retrospective study was to evaluate the safety and efficacy of bioabsorbable magnesium (Alloy: MgYREZr) screws in tibial tubercle osteotomy (TTO) fixation. METHODS: Ten patients with objective patellar instability who underwent distal realignment procedure using Fulkerson TTO were retrospectively reviewed. The osteotomy was secured with two parallel 4.8 mm magnesium screws in all patients. Kujala score and Lysholm knee score were used to assess the functional outcomes before and after the operation. Union of the osteotomy, displacement, and other imaging findings were evaluated with serial knee radiographs during the follow-up. RESULTS: There were five male and five female patients with a mean age of 23.4±9.2 years (range, 15-45). The mean follow-up duration was 11.5±3.2 months (range,6-17 months). The osteotomy united in all cases at an average of 3 months. No infection or wound healing problems were seen. A significant increase in Kujala (p:.005) and Lysholm knee scores (p:.005) were recorded in all patients. CONCLUSION: The findings support that bioabsorbable magnesium screws can be safely used as an alternative fixation technique in TTO. Furthermore, it provides the advantage to eliminate the need for implant removal.

Anterior Tibial Artery and Its Clinical Importance in the Posterolateral Approach to the Tibial Plateau: An Angiographic Study on 219 Lower Limbs.

The anterior tibial artery (ATA) is the most critical anatomical structure at risk at the distal border of the posterolateral approach to the tibial plateau. This study aimed to use available lower extremity digital subtraction angiography (DSA) images to determine the distal safe limit of this approach by measuring the distance from the tibial joint line to the ATA where it pierces the interosseous membrane. Tibial plateau mediolateral width (TP-ML-W) and the perpendicular distances from the ATA to the tibial joint line and fibular head were measured on DSA images in 219 lower extremities. To normalize the distances according to the tibial dimensions, each distance was divided by the TP-ML-W, and a ratio was obtained. Popliteal artery branching pattern was categorized according to the classification proposed by Kim et al. Comparative analysis between right and left extremities, genders, and anatomical variations were performed. There were 102 male and 26 female subjects with a mean age of 60.7 ± 15.7 years (range, 17-92 years). Ninety-one subjects had bilateral lower extremity DSA; thus, a total of 219 extremities were analyzed. The TP-ML-W was wider in male (78.3 ± 7.0) than female (70.5 ± 7.3) subjects (p = 0.001). The ATA coursed through the interosseous membrane at 50.9 ± 6.9 mm (range, 37.4-70.2 mm) distal to the tibial plateau joint line, and it was 66.5 ± 7.2% of the TP-ML-W. The ATA coursed through the interosseous membrane at 36.5 ± 6.0 mm (range, 21.9-53.8 mm) distal to the fibular head, and it was 47.7 ± 6.6% of the TP-ML-W. All measured variables were similar between the regular branching pattern of the popliteal artery (type 1A) and other observed variations among male subjects. The safe length of dissection in the posterolateral approach is average 66.5% (range, 45.7-86.7%) of the TP-ML-W. This ratio is valid for both genders. The use of a ratio instead of a distance, which is subject to personal variations, seems to be more logical and practical for planning this surgery, but the wide range should still not be ignored.

Alterations in magnetic resonance imaging characteristics of bioabsorbable magnesium screws over time in humans: a retrospective single center study.

OBJECTIVES: This study aimed to examine the alterations in magnetic resonance imaging (MRI) characteristics of bioabsorbable magnesium (Mg) screws over time in a single center study in humans. METHODS: Seventeen patients who underwent medial malleolar (MM) fracture or osteotomy fixation using bioabsorbable Mg screws and had at least one postoperative MRI were included in this retrospective study. Six of them had more than one MRI in the postoperative period and were subject of the artifact reduction measurements. 1.5T or 3T MRI scans were acquired in different periods in each patient. The size and extent of the artifact were assessed independently by two experienced radiologists both quantitatively (distance measurement) and qualitatively (Likert scale). RESULTS: In the quantitative measurements of the six follow-up patients the screw's signal loss artifact extent significantly decreased over the time, regardless of the MRI field strength (p<0.001). The mean artifact reduction was 0.06 mm (95% confidence interval [CI]: 0.05-0.07) for proton density weighted [PDw] and 0.04 mm (95% CI: 0.03-0.05) for T1 weighted (T1w) sequences per week. The qualitative assessments similarly showed significant artifact reduction in all MRI sequences. Different imaging findings, like bone marrow edema (BME), liquid collections, and gas formation were reported. The overall inter-reader agreement was high (κ=0.88, p<0.001). CONCLUSIONS: The time-dependent artifact reduction of Mg screws in postoperative controls might indicate the expected self-degradation of the Mg implants. In addition, different MRI findings were reported, which are characteristic of Mg implants. Further MRI studies are required to get a better understanding of Mg imaging properties.

Is There a Role of Meniscal Morphology in the Risk of Noncontact Anterior Cruciate Ligament Rupture? A Case-Control Study.

The purpose of this study was to identify the anatomical risk factors and determine the role of meniscal morphology in noncontact anterior cruciate ligament (ACL) rupture. A total of 126 patients (63 with noncontact ACL rupture and 63 age- and sex-matched controls) with intact menisci were included in this retrospective case-control study. On knee magnetic resonance imaging (MRI), meniscal morphometry (anterior, corpus, and posterior heights and widths of each meniscus), tibial slope (medial and lateral separately), notch width index, roof inclination angle, anteromedial bony ridge, tibial eminence area, and Q-angle measurements were assessed. The data were analyzed using multiple regression analyses to identify independent risk factors associated with ACL rupture. Using a univariate analysis, medial and lateral menisci anterior horn heights (p < 0.001; p < 0.003), medial and lateral menisci posterior horn heights (p < 0.001; p < 0.001), lateral meniscus corpus width (p < 0.004), and notch width index (p < 0.001) were significantly higher in the control group. Lateral tibial slope (p < 0.001) and anteromedial bony ridge thickness (p < 0.001) were significantly higher in the ACL rupture group. Multivariate analysis revealed that decreased medial meniscus posterior horn height (odds ratio [OR]: 0.242; p < 0.001), increased lateral meniscus corpus width (OR: 2.118; p < 0.002), increased lateral tibial slope (OR: 1.95; p < 0.001), and decreased notch width index (OR: 0.071; p = 0.046) were independent risk factors for ACL rupture. Notch stenosis, increased lateral tibial slope, decreased medial meniscus posterior horn height, and increased lateral meniscus corpus width are independent anatomical risk factors for ACL rupture. Meniscal morphological variations also play a role in ACL injury. This is a Level III, retrospective case-control study.