Evaluating the Suitability of the Plantaris Tendon for Sports Trauma Reconstruction and a Predictive Model of Tendon Length Based on Height and Leg Length.

This study evaluates the suitability of the plantaris tendon (PT) as a tendon graft donor for sports trauma reconstruction and proposes a predictive model for estimating PT length by using an individual's height and leg length. Anatomical dissection of 50 cadavers (32 males and 18 females) yielded precise measurements of PT length and width while also recording height and leg length. Among the lower limbs, 89% were suitable for at least one recommended graft suitability criterion. In addition, PT length exhibited robust positive correlations with height and leg length. Predictive equations were established for estimating the PT length based on leg length and height with consistency across sexes and sides: PT length = 0.605 + 0.396 × leg length (r = 0.721) and PT length = 1.480 + 0.193 × height (r = 0.626). This study underscores the grafting potential of the PT, providing a predictive tool that can aid surgeons in addressing tendon graft challenges within sports trauma scenarios.

Normal Distal Tibiofibular Syndesmosis Assessment Using Postmortem Computed Tomography (PMCT).

BACKGROUND: Distal tibiofibular syndesmotic injuries, often misdiagnosed, can lead to substantial morbidity. This study utilized postmortem computed tomography (PMCT) to define normal syndesmotic relationships in 131 subjects. METHODS: Three parameters were measured: fibular rotation (FR), sagittal translation (ST), and incisura depth (ID). RESULTS: Interobserver reliability was excellent for FR and ID but moderate for ST. Anatomical variability was wide, with FR ranging from -0.4° to 16.6°, ST from 0.33 mm to 3.49 mm, and ID from 1.89 mm to 6.05 mm. Side-to-side variability within subjects was minimal. Gender-specific differences were observed in ST, possibly due to size variations, highlighting the need for gender-specific diagnostic criteria. CONCLUSIONS: Although establishing universal reference values is challenging, using contralateral ankles for comparison can enhance diagnostic accuracy in syndesmotic injuries. This study, the first of its kind, offers valuable insights into normal distal tibiofibular syndesmotic relationships based on PMCT data. Future validation studies in patients with syndesmotic injuries can further improve diagnostic accuracy.

Estimating Adult Stature Using Metatarsal Length in the Korean Population: A Cadaveric Study.

This study aims to propose a regression equation for estimating stature in the Korean population using metatarsal bones from cadavers and to validate the appropriateness of the Korean-specific equation by comparing it to equations from other populations. A total of 81 adult formalin-fixed cadavers (51 males and 30 females) were evaluated. The first and second metatarsal bones' physiological and maximal lengths were measured, and the cadaveric stature of the subjects was determined as the distance from the vertex to the plantar face of the heel. In all measurements, the correlation coefficient between real stature and metatarsal length was statistically significant (p < 0.001). Additionally, both sexes showed a correlation between stature and metatarsal bone length. For unknown sex, M1 (first metatarsal maximal length) showed the strongest association between stature and metatarsal length. The following is the appropriate regression equation: 1172.4913 + 7.3275M1 (R = 0.703). The current equation demonstrated a statistically significant appropriateness for the Korean population when compared to equations for other populations (p < 0.001). In conclusion, we proposed a Korean-specific regression equation for estimating stature using metatarsal length, and this formula may be more appropriate and useful in forensic science for the Korean population.

Anatomical Characteristics of Extensor Hallucis Longus Tendon Variations and Its Clinical Implications: A Korean Cadaveric Study.

The purpose of this study is to ascertain the morphological characteristics of the extensor hallucis longus (EHL) tendon variation using larger-scale dissection of Korean cadavers and to classify the types of variation along with incidence. A total of 158 feet from adult formalin-fixed cadavers (50 males, 29 females) were dissected. The morphological characteristics and measurements of the EHL tendon variants were evaluated. Three types of the EHL tendon variation were classified, wherein the most common type was Type 2 (106 feet, 67.1%), Type 3 (3 feet, 1.9%) was the rarest type, and Type 1 without accessory tendon was found in 49 feet (31.0%). Type 2K (11 feet, 7%) and Type 3K (1 foot, 0.6%) were described as new subtypes. The present study suggests morphological characteristics of the EHL tendon variation in Korean populations and high morphological variability of the EHL tendon along with the possibility of differences according to race or ethnicity and gender. Furthermore, a newly updated classification complemented by new subtypes of variation will help foot and ankle surgeons in diagnosis and surgical planning with hallux problems.

The Comparison of Lower Extremity Length and Angle between Computed Radiography-Based Teleoroentgenogram and EOS® Imaging System.

Background and objectives: The differences between computed radiography-based teleoroentgenograms (CR-based teleoroentgenograms) and an EOS® imaging system were evaluated by measuring lower extremity lengths and alignments. Materials and methods: The leg length [L], femur length [F], tibia length [T], and hip−knee−ankle (HKA) angle were measured in 101 patients with lower extremity disease by a CR-based teleoroentgenogram with computed radiography and an EOS®. The additive length of the femoral and tibial segments (F + T) was determined by adding the two length values. Then, the differences among all five parameters between the two techniques were analyzed. The magnification (mm) was calculated by subtracting the length measurements on the EOS® from those in the scanogram. Furthermore, the magnification percentage (%) was calculated by dividing the magnification with the measurements on the EOS®. Results: The magnification errors (mean ± standard deviation), when comparing both right and left sides, were 7.80 ± 1.41%, 7.3 ± 6.01%, 5.16 ± 1.25%, and 6.45 ± 0.94% for L, F, T, and F + T, respectively. For limb length, the CR-based teleoroentgenogram had an average magnification of 6.8% (range, 5.2 to 7.8%) compared to the EOS® imaging. The two groups displayed a statistical difference (p < 0.01), except for the HKA angle. Conclusions: The CR-based teleoroentgenogram had a magnification of about 6.8% compared to the EOS® imaging system in evaluating lower extremity length. Therefore, more attention must be given to CR-based teleoroentgenograms to correct angular deformities.

Anatomical Classification for Plantaris Tendon Insertion and Its Clinical Implications: A Cadaveric Study.

The purposes of this study were to ascertain the morphological characteristics of a plantaris tendon (PT) insertion using a larger-scale dissection of Korean cadavers and to classify the types of PT insertion related to the calcaneal tendon (CT). A total of 108 feet from adult formalin-fixed cadavers (34 males, 20 females) were dissected. The morphological characteristics and measurements of the PT insertion were evaluated. Five types of PT insertion were classified, wherein the most common type was Type 1 (39 feet, 63.1%). Type 2 and Type 3 were similar, with 16 feet (14.8%) and 15 feet (13.9%), respectively. Type 4 (6 feet, 5.6%) was the rarest type, and Type 5 had 25 feet (23.1%). The case of an absent PT was noted in 7 feet (6.5%). In the proximal portion, the tendon had a thick and narrow shape, became thin and wide in the middle portion, and then changed to thick and narrow again just before the insertion into the calcaneal tuberosity. This study confirmed the five types according to the location of the PT and the area of its insertion-related CT. The morphology of the PT insertion may be anatomically likely to influence the occurrence of tendinopathy in the CT.

A Simple Method to Locate the Master Knot of Henry Using the Correlation between the Flexor Tendon Length Parameter and the Foot Length.

The precise location of the Master Knot of Henry (MKH) has important clinical significance, but its anatomical definition has not been agreed upon. The purpose of this study is to present a linear regression equation for predicting length variables based on foot length, by evaluating the correlation of length variables related to flexor hallucis longus (FHL) and flexor digitorum longus (FDL), with respect to the location of the MKH. A total of 95 limbs were dissected from 48 adult cadavers, and were fixed in formalin. Measurements were made for the length parameter, with reference to the landmark. The relevance between length variables was analyzed through simple correlation analysis and linear regression analysis. The foot length was 213.69 ± 17.53 mm, MKH-great toe distal phalanx was 140.16 ± 14.69 mm, MKH-FHL insertion was 124.55 ± 13.46 mm, MKH-little toe distal phalanx was 121.79 ± 13.41 mm, MKH-FDL little toe insertion was 109.07 ± 14.16 mm, and the FHL-FDL angle was 33.15 ± 5.39. The correlation coefficient between all the length variables for foot length showed a high positive correlation. We derived a regression equation that can predict the length of each variable. This regression formula is considered to be highly useful because it can estimate the positional relationship of the MKH relatively simply.

A New Anatomical Classification for Tibialis Posterior Tendon Insertion and Its Clinical Implications: A Cadaveric Study.

The variations in the tibialis posterior tendon (TPT) could not be defined by previous classification; thus, this study used a larger-scale cadaver with the aim to classify the types of TPT insertion based on the combination of the number and location of TPT insertions. A total of 118 feet from adult formalin-fixed cadavers were dissected (68 males, 50 females). The morphological characteristics and measurements of TPT insertion were evaluated. Four types of TPT insertions were classified, wherein the most common type was type 4 (quadruple insertions, 78 feet, 66.1%), which was divided into four new subtypes that were not defined in the previous classification. The second most common type was type 3 (triple insertions, 25 feet, 21.2%) with three subtypes, including the new subtype. Type 2 was found in 13 feet (11%), and the rarest type was type 1 (2 feet, 1.7%), wherein the main tendon was only attached to the navicular bone and the medial cuneiform bone. We suggest high morphological variability of the TPT in relation to the insertion location, along with the possibility of significant differences according to race and gender. Moreover, this classification will help clinicians understand adult flatfoot deformity-related posterior tibial tendon dysfunction (PTTD).

Effects of the Suboccipital Muscle Inhibition Technique on the Range of Motion of the Ankle Joint and Balance According to Its Application Duration: A Randomized Controlled Trial.

This study aimed to investigate the effects of suboccipital muscle inhibition technique (SMIT) on active range of motion (AROM) of the ankle joint, lunge angle (LA), and balance in healthy adults, according to the duration of its application. A total of 80 participants were randomly allocated to the 4-min suboccipital muscle inhibition (SMI) group (SMI_4M, n = 20), 8-min SMI group (n = 20), 4-min sham-SMI (SSMI) group (n = 20), and 8-min SSMI group (n = 20). Accordingly, the SMIT and sham SMIT were applied for 4 min or 8 min in the respective groups. AROM of dorsiflexion and LA were assessed, and a single leg balance test (SLBT) was performed before and after the intervention. AROM (4 min, p < 0.001; 8 min, p < 0.001), LA (4 min, p < 0.001; 8 min, p < 0.001), and SLBT (4 min, p < 0.001; 8 min, p < 0.001) significantly improved after SMI application. Compared with the SSMI group, the SMI group showed a significant increase in AROM (p < 0.001), LA (p < 0.001), and SLBT (p < 0.001). Except for SLBT (p = 0.016), there were no significant interactions between intervention and application duration. The results suggest that the SMIT, at durations of both 4 and 8 min, could be effective tools for improving AROM, LA, and balance.

The Location of the Fibular Tunnel for Anatomically Accurate Reconstruction of the Lateral Ankle Ligament: A Cadaveric Study.

We aimed to describe the location of fibular footprint of each anterior talofibular ligament (ATFL) and calcaneofibular ligament (CFL), as well as their common origin in relation to bony landmarks of the fibula in order to determine the location of the fibular tunnel. In 105 ankle specimens, the center of the footprints of the ATFL and CFL (cATFL and cCFL, respectively) and the intersection point of their origin (intATFL-CFL) were investigated, and the distances from selected bony landmarks (the articular tip (AT) and the inferior tip (IT) of the fibula) were measured. Forty-two (40%) specimens had single-bundle ATFL, and 63 (60%) had double-bundle patterns. The distance between intATFL-CFL and IT was 12.0 ± 2.5 mm, and a significant difference was observed between the two groups (p = 0.001). Moreover, the ratio of the intATFL-CFL location based on the anterior fibular border for all cadavers was 0.386. The present study suggests a reference ratio that can help surgeons locate the fibular tunnel for a more anatomically accurate reconstruction of the lateral ankle ligament. Also, it may be necessary to make a difference in the location of the fibular tunnel according to the number of ATFL bundles during surgery.

Independent muscle of extensor hallucis capsularis: a cadaveric case report.

Extensor hallucis capsularis (EHC) is an accessory tendon located medially to extensor halluces longus (EHL) tendon. Most EHC is known to originate as a tendinous slip of the EHL tendon, although it may be splitted from the tibialis anterior (TA) tendon or the extensor halluces brevis (EHB) tendon. During routine dissection of a 49-year-old male cadaver, independent muscle bellies of EHC were discovered bilaterally. The EHL muscle arose from the middle anteromedial aspect of fibula, lateral to the origin of TA muscle and medial to extensor digitorum longus (EDL) muscle. An additional muscle bellies were separated from EHL muscle at the point of 6 cm away from EHL origin in the right leg, and 3 cm away in the left. They coursed downward as EHC to reach the first metatarsophalangeal joint capsule. This muscle, unlike the variations identified to date, is considered to extend to EHC, and the name "extensor hallucis capsularis muscle" is offered. This kind of variation may be important for investigating the development of deformity at the first metatarsophalangeal joint, such as hallux valgus.

A Cadaveric Study of the Distal Biceps Femoris Muscle in relation to the Normal and Variant Course of the Common Peroneal Nerve: A Possible Cause of Common Peroneal Entrapment Neuropathy.

The most frequent mononeuropathy in the lower extremity has been reported as the common peroneal nerve entrapment neuropathy (CPNe) around the head and neck of the fibula, although the mechanism of the neuropathy in this area cannot be fully explained. Therefore, the aim of this cadaveric study was to evaluate the relationship between morphologic variations of the distal biceps femoris muscle (BFM) and the course of the common peroneal nerve (CPN) and to investigate the incidence and morphological characteristics of anatomical variations in the BFM associated with CPNe. The popliteal region and the thigh were dissected in 115 formalin-fixed lower limbs. We evaluated consensus for (1) normal anatomy of the distal BFM, (2) anatomic variations of this muscle, and (3) the relationship of the muscle to the CPN. Measurements of the distal extents of the short and long heads of the BFM from insertion (fibular head) were performed. Two anatomic patterns were seen. First, in 93 knees (80.8%), the CPN ran obliquely along the lateral side of the BFM and then superficial to the lateral head of the gastrocnemius muscle. Second, in 22 cases (19.2%), the CPN coursed within a tunnel between the biceps femoris and lateral head of the gastrocnemius muscle (LGCM). There was a positive correlation between the distal extents of the short heads of the biceps femoris muscle (SHBFM) and the presence of the tunnel. The "popliteal intermuscular tunnel" in which the CPN travels can be produced between the more distal extension variant of the SHBFM and the LGCM. This anatomical variation of BFM may have a clinical significance as an entrapment area of the CPN in the patients in which the mechanism of CPNe around the fibula head and neck is not understood.

The incision strategy for minimizing sural nerve injury in medial displacement calcaneal osteotomy: a cadaveric study.

BACKGROUND: The skin incision for medial displacement calcaneal osteotomy (MDCO) often damages the sural nerve. We aimed to identify the practical reference area in which the surgeon can incise the skin to minimize the injury of the sural nerve during MDCO. METHODS: The foot and ankles of 20 cadavers were dissected. The landmarks were the following four anatomical references: point A, the tip of the lateral malleolus; point B, the inferior margin of the calcaneus on the vertical line through point A; point C, the posteroinferior apex of the calcaneus; and point D, the lateral border of the Achilles tendon on the horizontal line through point A. The distances from the sural nerve to points A and B in the vertical direction (lines D1 and D2, respectively), to points A and C in the diagonal direction (lines D3 and D4, respectively), and to points A and D in the horizontal direction (lines D5 and D6, respectively) were measured. RESULTS: The median ratios of D1 to D1+D2, D3 to D3+D4, and D5 to D5+D6 were 0.34 (range 0.25 to 0.45), 0.23 (range 0.16 to 0.33), and 0.38 (range 0.26 to 0.50), respectively. CONCLUSIONS: The distance ratios according to easily identifiable references would be a more practical incision strategy for surgeons to minimize sural nerve injury in both open and minimally invasive/percutaneous MDCO.

Can sural nerve injury be avoided in the sinus tarsi approach for calcaneal fracture?: A cadaveric study.

There is no consensus regarding the references to determine the exact location of the skin incision to minimize iatrogenic sural nerve injury in the sinus tarsi approach for calcaneal fracture.The purpose of this cadaveric study was to describe the anatomical course of the sural nerve in relation to easily identifiable landmarks during the sinus tarsi approach and to provide a more practical reference for surgeons to avoid sural nerve injury.Twenty-four foot and ankle specimens were dissected. The bony landmarks used in the following reference points were the tip of the lateral malleolus (point A), lateral border of the Achilles tendon on the collinear line with point A (point B), posteroinferior apex of the calcaneus (point C), inferior margin of the calcaneus on the plumb line through point A (point D), and tip of the fifth metatarsal base (point E). After careful dissection, the distances of the sural nerve to points A and B in the horizontal direction (lines D1 and D2), points A and C in the diagonal direction (lines D3 and D4), points A and D in the vertical direction (lines D5 and D6), and points A and E in the diagonal direction (lines D7 and D8) were measured.The median ratio of D1 to D1+D2, D3 to D3+D4, D5 to D5+D6, and D7 to D7+D8 were 0.37 (range, 0.26-0.50), 0.23 (range, 016-0.33), 0.35 (range, 0.25-0.45), and 0.32 (range, 0.20-0.45), respectively.The distance ratios from this study can be helpful to avoid sural nerve injury during the sinus tarsi approach for calcaneal fractures. Established standard incision may have to be modified to minimize sural nerve injury.

Unusual variant of distal biceps femoris muscle associated with common peroneal entrapment neuropathy: A cadaveric case report.

RATIONALE: The anatomical variant of the distal biceps femoris muscle with regard to common peroneal nerve entrapment neuropathy (CPNe) was suggested through magnetic resonance images (MRI) study. PATIENT CONCERNS: An unusual variant of distal biceps femoris muscle was observed in 78 years old male cadaver. DIAGNOSES: The short head of biceps femoris muscle (SHBFM) was extended more distal and posteriorly. INTERVENTION: The popliteal area was dissected at knee joint level in a cadaveric limb. OUTCOMES: Common peroeal nerve (CPN) was situated within tunnel formed between the lateral head of the gastrocnemius muscle (LGCM) and the SHBFM. Also, the length of tunnel was 4.4 cm. LESSONS: The case illustrated here, to the best of our knowledge, is the first one with cadaveric findings of variant of distal biceps femoris muscle associated with CPNe. The tunnel formed between the more posterior or distal extension of the SHBFM and the LGCM could be possible entrapment area of CPN, clinically.