The effect of hallux valgus on the anatomy of the nerves around the first metatarsal bone

OBJECTIVE

To identify the variations in the location of the nerves that may be at risk in hallux valgus (HV) surgery, and to reveal whether these nerves are affected by the anatomical changes associated with HV.

METHOD

In the formalin fixed, 46 lower extremities (19 female, 27 male) (9 normal, 14 mild HV, 21 moderate/severe HV), extensor hallucis longus tendon (EHL), deep plantar artery, medial dorsal cutaneous (MDCN), deep fibular (DFN), common plantar digital (CPDN) and proper plantar digital (PPDN) nerves were examined. The branches of MDCN extending to the medial side of foot were recorded in three segments. The positional topography of nerves according to EHL were analyzed on 360° circle and clock models.

RESULTS

Sex-related differences observed in some parameters in direct measurements were not found in the clock model comparisons. In advanced HV angles (> 20°), DFN was closer to EHL in the distal part of the metatarsal bone, while there was no difference in the proximal. The intersection of the medial branch of the MDCN with the EHL was more proximal in HV cases than in normal feet. The location of the nerves in the clock pattern did not change in HV. Of the nerve branches reaching the medial side of the foot, 65.2% were in Part I, 71.7% in Part II, and 4.3% in Part III.

CONCLUSION

Sex differences in the distance of the nerves to the EHL disappeared when the size effect of the cross-section of the first metatarsal bone region was eliminated with the clock model. Only in advanced HVA (>20°) (not in mild HV), the DFN being closer to the EHL distally and the intersection of the medial branch of the MDCN with the EHL in HV being more proximal than in normal can be interpreted as specific reflections of HV progress. The variations we revealed in the number of branches reaching the inside of the foot may explain the diversity of neuromas or nerve injuries associated with HV surgery.

Connection between medial dorsal cutaneous nerve and saphenous nerve: case report

PURPOSE

There are no data on the connection of the saphenous nerve (SN), located on the medial side of the foot, with the terminal branches of the superficial fibular nerve. The aim of this study is to reveal the variation that surgeons should pay attention to for anesthesia applied in foot surgeries.

METHODS

In this study, the left foot of a 70-year-old female cadaver fixed with formalin was dissected. The distance to the medial malleolus and the incision line was recorded using digital caliper to determine the reference points in the resulting variation.

RESULTS

It was observed that a branch from the SN, which arose from the SN and proceeded anteriorly to the upper part of the medial malleolus and continued towards the dorsum of the foot, hooked with a branch from the medial dorsal cutaneous nerve (MDCN). The branches arising from this hook were distributed on the medial edge of the foot up to the proximal metatarsophalangeal joint I. The distance of this nerve connection to the medial malleolus is 91.14 mm, and the distance to the incision line is 15.76 mm.

CONCLUSIONS

It is suggested that the case presented as an unusual SN variation, which may affect the success of local anesthesia in invasive procedures to the medial part of the foot and could be considered in the evaluation of sensory loss after anteromedial surgical approach to the ankle, should be included in the classification of the cutaneous innervation pattern of the foot.

Morphological features of the chiasma tendinum and its relation with surface landmarks and pulleys: a cadaveric study

Aim

Chiasma tendinum (Camper’s chiasm) is of great importance in the delicate movements and stability of the fingers and takes place poorly in the literature. This study aims to reveal the morphometric details of the chiasma tendinum in relation with pulleys and other relevant structures.

Materials and methods

Palm and 2nd to 5th fingers of 10 (6 male, 4 female) formalin fixed cadavers were used bilaterally. After determining the superficial reference points on the fingers, the skin and the tendon sheath were incised, and then measurements of chiasma tendinum and related tendons were performed. The measurements were analyzed with respect to fingers, genders, and sides. Finally, the types of chiasma tendinum were identified and then grouped as symmetrical, asymmetrical, and pseudo chiasm.

Results

Pulley and chiasma tendinum positions were correlated with finger length (p < 0.01). Pulley lengths were significantly less in females. Asymmetrical chiasma tendinum types were found in 45% of the fingers. In most comparisons, values for fifth finger were significantly different than that of other fingers and chiasma tendinum types differed according to fingers and gender. The case of no fiber exchange was observed only in the 5th finger in 15%.

Conclusion

Findings related to the prediction of location of the pulleys and chiasma tendinum according to the superficial signs, awareness of cases where one of the two arms of the flexor digitorum superficialis is extremely thin and no fiber exchanges that may be risk factors for spontaneous tendon rupture may help provide more accurate approaches in relevant clinical applications.

Autopsy findings of an isolated persistent left superior vena cava in an intrauterine dead fetus

Persistent left superior vena cava (PLSVC) is one of the cardiac system abnormalities with a 0.3-0.5% incidence and caused by inadequate obliteration of the left anterior cardinal vein during embryonic development. Prognosis of PLSVC is generally assumed to be good if it is not accompanied by other cardiac system abnormalities. During the routine ultrasound control of a patient at 25th week of pregnancy at the Obstetrics and Gynecology Department of Mersin University, PLSVC anomaly was detected in an intrauterine fetus. Then, intrauterine death occurred and after removal of the deceased fetus, PLSVC diagnosis was confirmed by autopsy. According to the autopsy findings, right superior vena cava (SVC) and azygos vein were found in normal course. PLSVC opened into the right atrium via enlarged coronary sinus. There was no connection between the two SVCs. On the left side of posterior mediastinum, instead of hemiazygos or accessory hemiazygos veins, a vein symmetrical to azygos was opened into PLSVC, similar to the one on the right. No other cardiac anomaly associated with PLSVC or any other pathology in the other parts of body that could be responsible for death was discovered during autopsy. There was no evidence indicating that PLSVC played any role in intrauterine exitus of the present case. However, as mentioned in the literature, the ectopic beats in the atrium wall of patients with isolated PLSVC and enlarged coronary sinus may lead to pathologies in the conduction system of the heart. Considering the intrauterine death of an isolated PLSVC case associated with cardiac conduction pathologies, we recommend that the common assumption of 'isolated PLSVC is not associated with death' should be reviewed by studies on large series and even intrauterine cases should be closely monitored for cardiac arrhythmia.

Iliocapsularis muscle in human fetuses

PURPOSE

To determine the incidence of the iliocapsularis muscle in fetal period and its relationship with the hip joint capsule.

METHODS

Twenty-one formalin-fixed fetuses (12 female and 9 male) with a mean gestational age of 29 ± 3.89 weeks (range 25-36) were dissected to reveal morphological properties of iliocapsularis muscle.

RESULTS

Iliocapsularis muscle was observed in 39 out of 42 sides (92%). Its proximal attachment was detected either below the proximal attachment of rectus femoris muscle in 21 out of 39 sides (54%), or it was forming a common tendon with rectus femoris on the anterior inferior iliac spine in 10 out of 39 sides (26%), or it was forming an arch along the superior-medial-inferior sides of the proximal attachment of rectus femoris muscle in 8 out of 39 sides (20%). Muscle fibers originating from the anteromedial part of hip joint capsule were also constant in all sides. Distal attachment of iliocapsularis muscle was distal to the lesser trochanter in all specimens. Its form was as a broad muscle in 32 out of 39 sides (82%) and as a thin rectangular muscular slip in 7 out of 39 sides (18%). Iliopsoas and iliocapsularis muscles had their particular fascia in 34 out of 39 sides (87%), and in the other 5 sides, there was no fascia which prominently separated the two muscles. Its length was longer in females than males (p = 0.031) and it was wider on the right side (p = 0.029). Linear functions were y = 0.49 + 0.17 × weeks and y = 6.94 + 0.89 × weeks for width and length, respectively.

CONCLUSION

Data obtained with the present study about iliocapsularis muscle in fetal period revealed that it is an individual and constant muscle. Its dimension, location, and course over the hip joint capsule support the idea that it tightens the hip capsule and stabilizes the femoral head.

Evaluation of the stapedial tendon growth dynamic in human fetuses

PURPOSE

The main objective of the study was to investigate the morphometric properties of the stapedial tendon (ST) for pediatric otosurgeons and anatomists.

METHODS

The present study was placed on 15 fetuses (8 females, 7 males) aged from 20 to 30 weeks of gestation (at mean, 24.27 ± 3.24 weeks) using the collection of the Anatomy Department of Medicine Faculty, Mersin University. All measurements were obtained with a digital image analysis software.

RESULTS

In terms of male/female or right/left comparisons, no statistically significant difference was found in relation with the numerical data of ST. The surface area, length, and width of ST were detected as follows: 0.61 ± 0.15 mm², 1.27 ± 0.30 mm, and 0.45 ± 0.08 mm, respectively. The absence of ST was observed in two fetuses with and without severe malformations. In another fetus with cleft lip and polydactyly, multiple abnormalities were bilaterally identified in the middle ear: (1) the absence of the incudostapedial joint and (2) the presence of an abnormal tissue attaching to the stapes. The abnormal tissue was determined to be irregular dense connective tissue using light microscope and electron microscope.

CONCLUSION

Our findings showed that ST did not proportionally grow according to increasing gestational weeks. In the light of the numerical data, we thought that similar to stapes, ST attains the adult size in the fetal period. As ST anomalies may accompany severe malformations (e.g., cleft lip, polydactyly or syndactyly) that can be easily detected on observation by clinicians, we suggest that the detailed examination of middle ear in newborns should be taken into account for early diagnosis of conductive hearing loss to prevent any management delays.

Anatomic and histological analyses of chiasma plantare and long flexor tendons of the foot on human fetuses

PURPOSE

The aim of present study was to reveal slip transfers related to flexor hallucis longus (FHL) and flexor digitorum longus (FDL) by dissection and to investigate detailed structure of chiasma plantare composed of FHL-FDL tendons and quadratus plantae (QP), with precise composition of the long flexor tendons of lesser toes by histological sections in human fetuses.

METHOD

Slip transfers related to FHL and FDL tendons were identified and the related morphometric measurements were taken with dissection in 28 formalin-fixed fetuses (25-40 weeks). Composition and restoration of chiasma plantare and long flexor tendons of lesser toes were traced histological by analyzing movements of the tissues on the sequential coronal sections in five fetuses in the third trimester. The numbers of layers constituting chiasma plantare and the muscles that formed layers were specified. Each of two to five flexor tendons arising from the chiasma plantare was analyzed regarding its formation and contribution of FHL slip.

RESULTS

Slip transfers were found as FHL slip in 86% and cross-connections in 14%. The ratios of the slip width to that of FHL and FDL tendons were found higher than in adult literature. Variance in the involvement of slip to FDL and QP, formation and layering of chiasma plantare and formation of long flexor tendons from chiasma plantare were revealed and great similarities were found with data from dissection of adult in literature.

CONCLUSION

Slip transfers between FHL and FDL tendons, and layering properties of chiasma plantare were largely finalized during intrauterine period, while structural changes in slip seem to continue in the later stages of life, possibly by the effects of growth and usage of the extremity. In addition to individual variations, investigating the contribution of FHL slip, FDL and QP to long flexor tendons by different methods in literature is also suggested to be responsible for some diversities of our histological study.

Fetal anatomy of the facial nerve trunk and its relationship with posterior auricular artery

PURPOSE

The aims of the study are to define anatomy of the facial nerve (FN) and its main trunks as well as their relationship with the posterior auricular artery in fetal period to evaluate the data for regional surgery in newborns and young infants.

METHODS

Formalin-fixed 34 fetuses from anatomy laboratory collection with a mean gestational age of 26.4 ± 4.6 (20-36) weeks were dissected. Parameters regarding the presence of major or minor trunks, width, length, branching pattern of FN were evaluated according to side, gender and trimester. The positional relationship of posterior auricular artery with the FN trunk was inspected.

RESULTS

On all sides only the major trunk of the FN was detected. For length and width parameters, there was no statistically significant difference for side and gender except for trimester. Linear functions were found as 0.329 + 0.025 × weeks for width and 5.264 + 0.185 × weeks for length. There are statistically significant linear relationships between width and length of the FN trunk and week parameters as r = 0.507, p < 0.001 and r = 0.484, p < 0.001, respectively. Posterior auricular artery crossed FN trunk laterally in 42 of 53 sides, medially in 9 sides while it was puncturing it proximally in 2 sides. In all cases, it was in close contact to the FN trunk. FN trunk showed bifurcation in 82% and trifurcation in 18%.

CONCLUSION

Dimensions of FN trunk, growth ratio and linear functions can be beneficial in understanding the fetal growth of FN trunk and its usage for grafts. Data about the relationship of the posterior auricular artery with FN trunk may be crucial in avoiding iatrogenic injuries during surgery in early ages.

Quantitative assessment of the growth dynamics of the teres major in human fetuses

PURPOSE

The main objective of the study was to examine the use of teres major (TM) as a flap in the pediatric surgeries from an anatomical perspective by: (1) revealing the growth dynamics of the developing TM; (2) assessing the possible interconnecting structures between TM and latissimus dorsi (LD); (3) exposing the innervation patterns of TM in human fetuses.

METHODS

Study was conducted on 50 fetuses (26 females and 24 males), on a mean gestational age of 22.86 ± 3.21 (range 18-30) weeks. All the measurements were collected with a digital caliper and a digital image analysis software. Additionally, structural relations between TM and LD were examined in detail and further classified.

RESULTS

No significant difference of side and sex was detected on TM measurements (p > 0.05). Linear functions for the surface area, width, length of the superior and inferior margins of TM were detected as follows: y = - 257.142 + 18.334 × age (weeks), y = - 5.497 + 0.545 × age (weeks), y = - 1.621 + 1.068 × age (weeks), and y = - 2.147 + 1.284 × age (weeks), respectively. As classified in five types, a number of 33 muscular or tendinous connections between TM and LD were detected. Musculo-tendinous slips from TM to triceps brachii (TB) were evident in four sides. Innervation of TM was observed to be providing by the lower subscapular nerve in all the cases.

CONCLUSION

First, linear functions, representing the developing fetal morphometry obtained by our study can be adapted for estimating the morphometric of this muscle in early childhood. Besides, acknowledging the diverse appointments of TM with the surrounding muscles such as LD and TB may facilitate the prevention of neurovascular structures and the application of surgical procedures during tendon transfers. In brief, our findings are highly potent to bring the attention of pediatric surgeons.