Palaeopathological Features of Leprosy:
A Pictorial Overview of Common Bone Changes
Leprosy is a chronic infectious disease mainly, but not solely, of man, and caused by Mycobacterium leprae. Bony changes only occur in a fraction of individuals with leprosy and only exhibit in late stages of the disease. Because the bacterium which causes leprosy has a predilection for cool environments, changes that occur are mainly in the bones of the face (the maxillae), hands (metacarpals, manual phalanges), legs (tibia and fibula), and feet (tarsals, metatarsals, pedal phalanges). Only changes in the face (maxillae), direct leprous osteomyelitis, and concentric diaphyseal remodelling are caused by the leprosy bacterium; all other bony changes are caused indirectly from trauma and introduction of other bacterium (e.g. staphylococcus). It is only by an examination of the total skeleton, and by recognition of the overall pattern of individual pathological skeletal elements, that a diagnosis of leprosy can be made and an inference made with regard to the specific clinical type of leprosy (tuberculoid or lepromatous) and the symptoms and physical signs shown in the once living person.
The pathological bones depicted in the following photos are mostly of late stage examples of leprous changes to bone. For more in-depth discussion of bone changes in leprosy and clinical features of the disease
see a clinical Synopsis for Palaeopathologists for further details
see BONE CHANGES IN LEPROSY: pathogenesis, palaeopathological diagnostic criteria, and clinical interpretation for a more detailed viewIntroduction to Bone Lesions
Subperiosteal new woven bone: Low density bone that forms on the bone surface, which has no clear pattern and represents an acute pathology. It is dark in colour and forms on the underlying bone.
Subperiosteal new compact bone: High density bone, which is of slow onset and development, lasting for a long period of time and is a sign of a chronic pathology.
|C024 Right Fibula||View Model||C035 Fibula Distal End||View Model||C035 Right Tibia||View Model||C048 Right Fibula||View Model||C048 Right Tibia||View Model||C339 Left Fibula||View Model||C339 Right Tibia||View Model|
Osteomyelitis: An infection of bone and bone marrow. It is usually caused by bacteria from an infection. Parts of the bone die and new bone is deposited. Pus collects in the inner cavity of the bone, which then drains out into the soft tissue.
|C353 Left 2nd Manual Intermediate Phalanx||View Model|
Cloaca: A hole and channel that drains pus from the interior of bone to the bone surfaces.
|C273 Right Navicular||View Model||C353 Left 2nd Manual Intermediate Phalanx||View Model|
Inflammatory pitting: Pitting of the bone surface that is caused by inflammation.
|C088 Pedal Middle Phalanx A||View Model||C088 Pedal Middle Phalanx C||View Model||C088 Pedal Proximal Phalanx A||View Model||C088 Right Cuboid||View Model|
Common Bony Changes in LeprosyMaxillae-Rhinomaxillary Syndrome:
Anterior nasal spine: There is a reduction or an absence of the spine through absorption of the bone.
Alveolar process of the maxillae: Absorptions and/or reduction of the bone that holds the first for front teeth (incisors).
|C341 Maxillae||View Model|
Nasal surface of the palatine process of the maxillae (PPMN): Inflammatory pitting with/or without new bone formation on the floor of the nasal cavity.
|C010 Maxillae||View Model||C341 Maxillae||View Model|
Oral surface of the palatine process of the maxillae: Inflammatory pitting of the bone that makes up the roof of the mouth.
|C010 Maxillae||View Model||C341 Maxillae||View Model|
Nasal aperture: Rounding of the margin of the nasal opening due to absorption of bone.
|C158 Maxillae||View Model|
Posterior alveolar margins of the maxillae: Recession of the bone above the posterior teeth, especially the third molar (wisdom tooth).
Tibiae and Fibulae (the Leg): Common features of tibial and fibular changes are subperiosteal new woven and compact bone formation and inflammatory pitting.
|C024 Right Fibula||View Model||C035 Fibula DistalEnd||View Model||C035 Right Tibia||View Model||C048 Right Fibula||View Model||C048 Right Tibia||View Model||C339 Left Fibula||View Model||C339 Right Tibia||View Model|
Hands and Feet:
Distal phalanges: Common changes are destruction and inflammatory pitting at the finger tips.
|C088 Right Hand 4th Distal Phalanx||View Model||C341 Manual Distal Phalanx||View Model|
Concentric diaphyseal remodelling: There is bone loss in the mid-section of the bone, causing a 'waisting'.
Palmar grooves: Semicircular groove that form at the distal end (the end furthest from the arm) in response to pressure from the adjoining phalanx being stuck in a flexed position (a sign or claw-hand deformity).
|C088 Right Hand 3rd Proximal Phalanx||View Model||C088 Right Hand 4th Proximal Phalanx||View Model|
Cupping and peg: Cupping (left) is an enlargement of the joint end and a peg (right) can form though loss of bone, which leaves only a remnant of the original bone.
|C088 Left Pedal 2nd Int Distal Phalanges||View Model||C235 Distal Intermediate Phalanges Fused||View Model||C339 Manual Proximal Phalanx D||View Model|
Knife-edge remodelling: There is bone loss and remodelling of the shaft, making the bone resemble a knife's edge (i.e. it gets thinner on both sides).
|C062 Left 3rd Metatarsal||View Model||C062 Left 4th-5th Metatarsal||View Model||C062 Right 5th Metatarsal||View Model||C088 Right 5th MetaTarsal||View Model||C088 Right 3rd MetaTarsal||View Model||C235 Left 5th Metatarsal||View Model|
Dorsal Tarsal bars: The ligament or tendon turns to bone at the attachment site.
|C088 Right Intermediate Cuniform||View Model|
Navicular squeezing: As the foot collapses, the navicular is compressed.
|C273 Right Navicular||View Model|
Ankylosis: Bones fuse together.
|C008 Left MedCun 1st MetaTarsal||View Model||C058 Left Cuboid||View Model||C088 Left Pedal 2nd Int Distal Phalanges||View Model||C235 Distal Intermediate Phalanges Fused||View Model||C235 Left 5th Manual Prox Int Phalanges||View Model|
Bone absorption/destruction: Bone is lost.
|C048 Left 1st Pedal Proximal Phalanx||View Model||C058 Left Pedal Proximal Phalanx A||View Model||C058 Left Pedal Proximal Phalanx B||View Model||C058 Left 2nd Metatarsal||View Model||C058 Left 3rd Metatarsal||View Model||C062 Left 3rd Metatarsal||View Model||C062 Left 4th-5th Metatarsal||View Model||C062 Right 3rd Metatarsal||View Model||C062 Right 4th Metatarsal||View Model||C062 Right 5th Metatarsal||View Model||C088 Left Hand 5th Mid Phalanx||View Model||C088 Right Foot 1st Proximal Phalanx||View Model||C235 Distal Intermediate Phalanges Fused||View Model||C235 Left 5th Metatarsal||View Model||C339 Manual Proximal Phalanx D||View Model|