Dermis and hypodermis

Cure Arthritis Naturally

Beat Arthritis Naturally

Get Instant Access

The skin represents the external covering of the whole body. Its thickness varies according to different body regions, reaching a maximum thickness at the palm of the hand and the sole of the foot. The skin is divided into two different layers; the external layer is the epidermis, consisting of squa-mous multistratified epithelium that continues deeply with the dermis, a layer of connective tissue made of cells and collagen fibers lying in an amorphous interstitial substance. The dermis contains blood vessels, nerves, lymphatics, hair follicles and glands.

The hypodermis is found even more deeply and it is made of a tissue rich in collagen fibers and connected to the dermis by fibrous branches. The hypodermis has a complicated structure containing adipose storage inside the subcutaneous adipose tissue. The hypodermal thickness varies according to the examined region and to the patient's personal constitution [14,23].

Detailed US exploration of the skin is now possible due to high frequency and high resolution transducers. The skin appears as a hyperechoic superficial band of variable thickness and homogeneous structure where it is not possible to differentiate the epidermis from the dermis by ultrasound. The hypodermis, on the contrary, is easily identifiable: it appears as a deep hypoechoic layer, characterized by intersecting curvilinear septa, that correspond to supporting fibrous branches, containing blood vessels well-depicted by color Doppler techniques. The hypodermis is separated from the underlying muscular layer by the superficial aponeurotic fascia, appearing as a double hyperechoic line (Fig. 3.26). Dynamic examination is useful to differentiate adipose from muscular tissue [32].

To diagnose skin disease, the main investigation tends to be clinical examination, eventually supported by histological analysis; US can be useful as a follow-up examination when assessing systemic diseases with skin involvement, such as systemic sclerosis (scleroderma).

Subcutaneous tissue ultrasound examination can also be useful in the diagnosis and staging of some neoplastic lesions such as melanoma, glomus tumours and hemangiomas. It is also used for anthropometric studies in sports medicine to calculate the fat-free mass, which represents an important indicator of physical condition for athletes.

Fig.3.26

Normal ultrasound appearance of epidermis-dermis (E), hypodermis (H) and superficial aponeurotic fascia (A)

Fig.3.26

Normal ultrasound appearance of epidermis-dermis (E), hypodermis (H) and superficial aponeurotic fascia (A)

References

1. Grassi W, Cervini C (1998) Ultrasonography in rheumatology: an evolving technique. Ann Rheum Dis 57:268-271

2. Grassi W,Lamanna G,Farina A,Cervini C (1999) Sonographic imaging of normal and osteoarthritic cartilage. Semin Arthritis Rheum 28:398-403

3. McCune WJ,Dedrick DK,Aisen AM,MacGuire A (1990) Sonographic evaluation of osteoarthritic femoral condy-lar cartilage. Correlation with operative findings. Clin Orthop 254:230-235

4. Martino F, Monetti G (1993) Semeiotica ecografica delle malattie reumatiche. Piccin ed., Padova

5. Sheperd DET,Seedhom BB (1999) Thickness of human articular cartilage in joints of the lower limb. Ann Rheum Dis 58:27-34

6. Aisen AM, McCune WJ,MacGuire A et al (1984) Sono-graphic evaluation of the cartilage of the knee. Radiology 153:781-784

7. Disler DG, Raymond E, May DA et al (2000) Articular cartilage defects: in vitro evaluation of accuracy and interobserver reliability for detection and grading with US. Radiology 215:846-851

8. Castriota-Scanderbeg A, De Micheli V, Scarale MG et al (1996) Precision of sonographic measurement of articular cartilage: inter- and intraobserver analysis. Skeletal Radiol 25:545-549

9. Backhaus M, Burmester GR, Gerber T et al (2001) Guidelines for musculoskeletal ultrasound in rheumatology. Ann Rheum Dis 60:641-649

10. Grassi W, Tittarelli E, Pirani O et al (1993) Ultrasound examination of metacarpophalangeal joints in rheumatoid arthritis. Scand J Rheumatol 22:243-247

11. Barnett CH, Davies DV, MacConaill MA (1961) Sinovial joints. Their structure and mechanics. Longman, London

12. Hlavacek M (1993) The role of synovial fluid filtration by cartilage in lubrification synovial joints. Squeeze film lubrification: homogeneous filtration. J Biomech 26:1151-1160

13. Mc Cutchen CW (1983) Joint lubrification. Bull Hosp Jt dis Orthop Inst 43:118-129

14. Balboni GC et al (1991) Anatomia Umana. Edi-Ermes, Milano

15. Grobbelaar N, Bouffard JA (2000) Sonography of the Knee, a pictorial review. Semin Ultrasound CT MR 21:231-274

16. Bianchi S, Martinoli C, Bianchi-Zamorani M, Valle M (2002) Ultrasound of the joints. Eur. Radiol 12:56-61

17. Wang SC, Chen RK, Cardinal E, Cho KH (1999) Joint sonography. Radiol clin North Am 37:653-668

18. Rindi G, Manni E (1990) Fisiologia umana. Utet, Torino

19. O'Brien M (1992) Functional anatomy ane physiology of tendons. Clin Sports Med 11:505-520

20. Stolinski C (1995) Disposition of collagen fibrils in human tendons. J Anat 186:577-583

21. Ling SC, Chen CF,Wang SC (1990) A study on the vascular supply of the supraspinatus tendon. Surg Radiol Anat 12:161-165

22. Davis WH,Sobel M,Deland J et al (1994) The superior peroneal retinaculum: an anatomic study. Fott Ankle Int 15:271-275

23. Testut L,Latarjet A (1964) Trattato di Anatomia Umana. Utet, Torino

24. Grechenig W, Clement H, Bratschitsch G et al (2002) Ultrasound diagnosis of the Achilles tendon. Orthopade 31:319-325

25. Bruce RK, Hale TL, Gilbert SK (1982) Ultrasonographic evaluation for ruptured Achilles tendon. J Am Pediatr Med Assoc 72:15-17

26. Martinoli C,Derchi LE,Pastorino C et al (1993) Analysis of echotexture of tendons with US. Radiology 186:839-843

27. Jozsa L, Kannus P, Balint JB, Reffy A (1995) Three-dimensional ultrastructure of human tendons. J Anat 142:306-312

28. Dillehay GL et al (1984) The ultrasonographyc characterization of tendons. Invest Radiol 19:338-341

29. Silvestri E, Biggi E, Molfetta L et al (2003) Power Doppler Analysis of tendon vascularization. Int J Tissue React 25:149-158

30. Grassi W, Filippucci E, Farina A, Cervini C (2000) Sonography imaging of the distal phalanx. Semin Arthritis Rheum 29:379-384

31. Bianchi S, Martinoli C,Abdelwahab IF (1999) High-frequency ultrasound examination of the wrist and the hand. Skeletal Radiol 28:121-129

32. Van Holsbeeck M, Introcaso JH (1992) Musculoskeletal Ultrasonography. Radiologic Clinics of North America 5:907-925

33. Narici MV, Maganaris CN, Reeves ND, Capodoglio P (2003) Effect of aging on human muscle and architecture. J Appl Phisiol 95:2229-2234

34. Erickson S (1997) High resolution imaging of the musculoskeletal system. Radiology 205:593-618

35. Balconi G (1993) Apparato locomotore: muscoli e tendini. In: Trattato italiano di ecografia. Poletto Edizioni,Milano

36. Reimens K, Reimens CS,Wagner S et al (1993) Skeletal muscle sonography : a correlative study of echogenicity and morphology. J Ultrasound Med 2:73-77

37. Scott JE (1997) High resolution imaging of the musculoskeletal system. Radiology 205:593-618

38. Bianchi S,Martinoli C, Sureda D, Rizzatto G (2001) Ultrasound of the hand. Eur J Ultrasound 14:29-34

39. Hall MC (1965) The locomotor system: functional anatomy. Thomas, Springfield, Illinois

40. Martinoli C, Bianchi S, Derchi LE (1999) Tendon and nerve sonography. Radiol Clin North Am 37:691-711

41. Beekman R,Visser LH (2004) High-resolution sonography of the peripheral nervous system: a review of the literature. Eur J Neurology 11:305-314

42. Silvestri E, Martinoli C, Derchi LE et al (1995) Echo-texture of peripheral nerves: correlation between US and histologic findings and criteria to differentiate tendons. Radiology 197:291-296

43. Martinoli C, Bianchi S, Gandolfo N et al (2000) US of nerve entrapments in osteofibrous tunnels of the upper and lower limbs. Radiographics 20:199-217

Was this article helpful?

0 0
Arthritis Relief Now

Arthritis Relief Now

When you hear the word arthritis, images of painful hands and joints comes into play. Few people fully understand arthritis and this guide is dedicated to anyone suffering with this chronic condition and wants relief now.

Get My Free Ebook


Post a comment