Friday, December 20, 2013

Case(s) of adult bone length growth

Control F for (*NEW*) for two breakthrough studies from 2004-2005 that provides evidence that LSJL can work on adults provided the stimulating caused by bite jumpling appliances(any experts on dentistry?) is to LSJL and how similar the mandible is to a long bone such as the tibia.  These two studies have been enhanced with new figures and analysis.

It has been shown that there is endochondral ossification involved in both osteoarthritis and that occurs in normal aging.  Why doesn't this articular cartilage ossification result in height increase?  Maybe enhancing this process of the articular cartilage can result in height increase of course you'd have to find a way preserve the articular cartilage from fully ossifying to maintain joint integrity.

The following studies serve as a bit of a proof of concept for adult bone length increase by showing that the two most distal of the three finger bones can increase in length with age and that the skull bone can increase in length.

Here are some selections from a statement by Roy Wuthier, a retired scientist in regards to non-growth plate methods of bone growth:

"Not all bone growth occurs via growth plate-dependent mechanisms.  The growth of phalanx bone apparently is not totally dependent on growth plate elongation.  As you realize, appositional growth can be mediated via osteoblasts that reside under the periosteal membrane.  Thus in phalanx bones, both types of bone growth must contribute to their expansion during overall skeletal growth."<-so perhaps on the proximal end of the phalanx bone there may be a periosteal membrane despite being separated by articular cartilage.

"During typical long bone growth (elongation), you will note that the ends of the long bones (where the growth plates reside) have a larger cross-sectional area than occurs at the mid-shaft.  The cells that sculpt the shape of the long bones are the osteoclasts which have the ability to remove bone.  In fact in a genetic disease where osteoclast formation is suppressed, the shape of the long bones is almost "post-like" with no reduction in mid-shaft cross-sectional area."<-Perhaps the larger cross-sectional area of the epiphysis formed by growth plate growth facilitates osteoclast absorption.  Thus, osteoclasts may be able to remove bone that is generated by endochondral ossification at a fast enough rate such that there is no net bone length increase.  And, in ends of the bones not formed by growth plates don't have as large a cross-sectional area favoring absorption thus apposition at the ends of the bones is greater than osteoclast resorption.

A way to test this is with osteoclast inhibitors however articular cartilage endochondral ossification is slow and osteoclasts are needed for many functions.  You could elevate HGH levels which increases both bone formation and resorption thus allowing you to safely lower osteoclast levels.  HGH would also increase the rate of the growth so it could occur in a reasonable time frame.  And then see if articular cartilage endochondral ossification could make you taller.

Metacarpophalangeal length changes in humans during adulthood: A longitudinal study

Metacarpophalangeal refers to hand bones essentially.

"Total lengths of the 19 diaphyseal hand bones were measured from standardized radiographs of healthy American whites as young adults (ca. 21 years) and again at ca. 55 years of age. The four hand-bone rows exhibit distinctive length changes: Distal and middle phalanges continue to increase significantly in length{the distal phalange may have periosteum at the distal end of the bone so it may be able to grow by appositional growth but that is not true of of the middle phalange}, proximal phalanges constitute a transition zone of little change, and metacarpals uniformly decrease in length[there are three bones in a non thumb finger.  The end bone is the distal bone and the one closest to the the end is the proximal phalange.  The metacarpals are part of the hand.]. Clear-cut sex differences are noteworthy: Males change more (lose more in some bone rows, gain more in others) than females. Progressive elongation was greatest in the distal phalanges where apposition around the distal aspect (“tufting”) is not constrained by a joint or epiphysis. Loss of bone length in the metacarpals by subchondral resorption is consistent with documented reductions in activity levels and grip strength with age, as well as diminished joint spaces which alter loading of the joints."

The increase in bone length was about 0.34 mm per decade.

"To test for [the possibility that the bone length gain was due to residual gain due to growth plate growth], we partitioned the sample into those cases whose younger-adult age at examination was less than 25 years and those with a radiograph after 25 years of age. Using a two-way  factorial analysis of variance, grouping by age grade and sex, none of the 19 tests achieved statistical  significance. "

"In the distal and middle phalanges most of  the increase was accounted for by progressive apposition at the distal, epiphysis-free ends of the bones"

If you look at the phalanx x-rays you can see that distal ends of the bones do not have a growth plate.


Only the proximal(closest to the body) side has growth plates.  Maybe bone growth can be renewed if you remove the epiphysis somehow.  LSJL via fluid based shear strain may degrade some of the epiphysis allowing for new height growth.

"the distal phalanges, which exhibit appreciable increase, are unique in not being constrained distally by a joint or epiphysis"

"When cartilage thickness exceeds the critical dimensions that limit nutrition by diffusion, the cartilage cells hypertrophy and degenerate, the spaces become vascularized, and osteoblasts develop to initiate endochondral bone formation in the midst of the articular cartilage."

Continuing bone growth throughout life: A general phenomenon

"Cross-sectional data on 2799 subjects from five different populations and longitudinal data on 113 older adults indicate continuing adult bone growth in the second metacarpal. Similar 6-decade increases in the size of the cranium confirm continuing bone growth as a general phenomenon not necesarily related to weightbearing or flexion stress and representing an increase of approximately 10% in skeletal volume concomitant with the major age-associated decrease in skeletal mass."

"there is a small but completely systematic three-decade gain in metacarpal width at mid-shaft  in  both sexes  and all  five  populations  sampled"

The scientists reported an increase in skull length.

Extreme elongation of the transverse processes of the fifth lumbar vertebra: an unusual variant.

"The fifth lumbar vertebra has massive transverse processes that are continuous with the pedicle and encroach the body of the vertebra. These processes are mainly meant for the attachment of the iliolumbar ligament. With increasing age, the iliolumbar ligament can undergo secondary degenerative changes such as calcification, hyalinization, and myxoid degeneration. [We discovered an] extremely elongated transverse processes of the fifth lumbar vertebra in a 45-year-old woman who underwent surgery for an intervertebral disc herniation. This unusual variant may be caused by calcification of the iliolumbar ligament rather than a congenital anomaly."

Causing calcification of ligaments isn't really reproducible but it's still bone length increase in a 45 year old.

If you look figure 1A and 1B you can see that the increase in transverse process is insane with the elongated transverse process being about 3 times longer than the other bones.

"[There was] a calcified nodular lesion in the left pelvic cavity, suggesting the presence of a calcified uterine myoma[mesenchymal tumor]."

"the trabecular bone of the transverse processes have normal shape and length, and the compact bone is elongated."

"[There was] a large, extruded intervertebral disc on the right side, compressing the dural sac."

"the direction of elongation of the transverse process corresponded to the position of the iliolumbar ligament."  Thus providing evidence that the iliolumbar ligament was calcified.

"The iliolumbar ligament is attached to the tip and the anteroinferior aspect of the transverse processes of the fifth lumbar vertebra"<-So the ligament may have been used as a scaffold to grow the bone longer.  Maybe a ligament can be inserted into a long bone so you can grow taller forever.

"the iliolumbar ligament does not exist at birth, but develops gradually in the first decade and attains full differentiation only in the second decade."


Mechanical strain leads to condylar growth in adult rats.

"Mechanical strain produced by forward mandibular positioning was found to enhance mandibular condylar growth in experimental animals and in patients. [We] identify the changes in number and rate of the proliferating mesenchymal cells in mandibular condyles of adult rats and to correlate these changes to the expression of SOX9 and type II collagen under mechanical strain. Seventy-eight 120-day-old female Sprague-Dawley rats{rats generally stop growing at six months} were randomly allotted to six groups, nine animals in each experimental group according to different time points. Cell kinetic studies for expression of PCNA were used to identify number and rate of proliferating mesenchymal cells. Immunostaining of SOX9 and in situ hybridization of Col2a1 gene were carried out. Results showed a significant increase in number of replicating mesenchymal cells and proliferation rate. The expression of SOX9 was enhanced and Col2a1 gene transcript was then activated. The proliferative layer became thicker on experimental day 21. The thickness of chondroblast layer and chondrocyte layer showed significant increase from experimental day 14 to day 30. Mechanical strain produced by mandibular advancement in adult rats promotes the proliferation of mesenchymal cells. Under control of transcription factor SOX9, these mesenchymal cells are then committed to enter the chondrogenic route leading to condylar growth."

Producing proliferating of MSCs which then differentiate into chondrocytes via SOX9 is exactly what we're trying to accomplish with LSJL.

"mandibular advancement reactivates endochondral ossification in the posterior condyle and ultimately results in new bone formation in the condyle"

"In the adult patients treated with Herbst appliance this would be the result of a reactivation of cells of prechondroblast zone, thus representing an area of active condylar growth"

"continuous bite jumping devices induce morphological adaptation in the mandible especially the length of condylar head in adult rats"

"During mandibular growth, the condyle undergoes endochondral ossification and the condylar cartilage acts as a template for bone growth. However, in the adults, the remnant condylar cartilage serves more 'articular' function than 'growth' function. From growing to adults, the thickness of cartilage becomes thinner. It has been reported that the adult rat's condyle is covered by a thin layer of cartilage, which is composed of 2-3 layers of chondrocytes and there is no obvious hypertrophic layer in the cartilage since a weak staining of Type X collagen, the marker of endochondral ossification, was obscured. This result implies that adult rat condyle stops growth or becomes inactive of endochondral ossification. Bone growth in the condyle is closely related to cartilage formation in the growing rats"

"The fibrous zone of the condylar cartilage of adult rats is composed of several layers of flattened cells . The cells in the proliferative layer, which was densely packed, located beneath the fibrous layer . Underneath the proliferative layer, the cells became chondrospecific and flattened gradually. The extracellular matrix was positively stained with type II collagen and thus this layer was termed as "type II collagen positive layer" in the present stud which may represent the level of expression of type II collagen. The current study showed that the thickness of cartilage in posterior condyle was apparently affected by the bite-jumping device. Analysis showed the thickness of each layer of cartilage in controls was unchanged during the observation period. In the experimental group, there were significant changes observed in all the layers. The thickness of fibrous layer showed significant increase from day 14 of mandibular advancement and was maintained from day 30 to day 60 Mandibular advancement resulted in an increase in the thickness of the proliferative layer on day 21 which was then followed by a decrease to the level found in the matched controls. The thickness of type II collagen positive layer showed a significant increase from experimental day 14. The highest level was presented on experimental day 21 followed by a lower level on day 30. The level of expression of type II collagen expressed on day 60 returned to the level expressed in the controls."

"The population [of MSCs] in that of mandibular advancement groups was significantly increased on day 21" No differences were observed in the control group.

"In the control groups, only a few SOX9 positive cells existed in the proliferative layer. On experimental day 3, SOX9 positive cells were remarkably increased in the proliferative layer of experimental animals. On experimental day 21, the SOX9 positive cells were increased in both proliferative layer and chondroblast layer but no positive staining can be detected in the hypertrophic chondrocyte"

"mandibular advancement in adult rats resulted in increase in condylar growth as measured by a significant increase in: the number and rate of replicating mesenchymal cells; the expression of transcription factor SOX9, the factor that regulates mesenchymal cell differentiation into chondroblasts; the thickness of cartilage layers and finally increase in the amount of osteocytes that led to increase in the production of new bone in the adult condyles "

I'm not sure how much a forward biting device is analagous to LSJL.  Maybe someone more familiar with dentistry can help out.

"[The] significant increase in SOX9 expression level coincided with the rate of proliferation of mesenchymal cells"

It should be noted that the population of MSCs began to decline after thirty days.  That may be related to an adaptative response and indicates that there may need to be a deconditioning period with LSJL after 30 days.

" Each group consisted of nine rats with bite-jumping appliances and four untreated controls"

On this page is an example of a bite jumping appliance(It's the Herbst) mentioned earlier.

Here's the picture of experimental jaw versus control:


I'm planning on looking for ectopic signs of cartilage formation later as that is what we're trying to induce with LSJL.  However there is some blue staining(which means it's positive for cartilage) on A but it is very faint. Note though that the entire shape of B(experimental) is different than A(control) so there must be some mechanism to achieve that.

"Alcian blue-PAS staining showing the overview of rat's TMJ condyle at age of 141-day (experimental day 21). The thickness of cartilage in the posterior condyle is remarkably increased by mandibular advancement (B) than that of control (A). Two measurement frames are illustrated on (B), one for the measurement of thickness of layers (1104×811µm, black) and the other frame for the cell counting (547×402µm, red)."
Here's the ectopic chondrogenesis highlighted with GIMP(blue line):



Here's the Col2a1 expression areas:

"In situ hybridization showing the localization of type II collagen (Col2a1) mRNA (marked with arrow) in the condylar cartilage of control (A) and experimental animal (C.D) on experimental day 21. (D) is higher magnification of (C). In situ hybridization with sense probe shows no hybridization signal in the cartilage (B)."  So there was no active COL2A1 mRNA production in B which is the control.
Arrows point to two possible areas where the bone ends both are distant from the Col2a1 staining indicating that the new growth plate formation is within the bone thus providing evidence for proof of concept for LSJL to form new growth plates within bone.

Forward mandibular positioning enhances condylar adaptation in adult rats.

"The aim of this investigation was to assess quantitatively the adaptive changes in the condyles of adult rats to forward mandibular positioning. The level of types II and X collagen expressed in the condyles of adult rats was compared with that formed in response to forward mandibular positioning and the levels of expression were correlated to the amount of bone formed in response to mandibular advancement. Seventy-eight 120-day-old female Sprague-Dawley rats were included in this study. The rats were randomly allocated to six groups. Each group consisted of nine rats with bite-jumping devices and four untreated controls. The animals in each group were sacrificed on days 3, 7, 14, 21, 30, and 60. Immunostaining was used for the detection of types II and X collagen, while Alcian blue-PAS was used to observe the extracellular matrix and new bone formation. New cartilage was formed in the posterior condyle. The highest level of expression of types II and X collagen were present on day 21, the amount of increase was 247.99 and 540.08 per cent, respectively. The highest level of new bone formation was measured at day 30 of advancement when the amount of increase in new bone formation was 318.91 per cent. Forward mandibular positioning causes changes in the biophysical environment of the temporomandibular joint (TMJ) of adult rats that leads to condylar adaptation."

The study won't let me copy and paste. When I get a chance, I might print the paper out and scan the images in. Click on the link and look at figure 2 for new cartilage growth.  Note in figure 2a that the region of new cartilage formation pointed to by the arrow is disconnected from the rest the cartilage.  Also note that there is red staining in scattered quantities throughout the entirety of the epiphysis with the exception of that attached to the bone attached to the new red zone.

Note that in figure 1 there is staining for Type II Collagen deep within the epiphysis in the control group.

In figure 3a there is staining for Type II collagen throughout the entire bone.  If you look at figure five bone formed downward furthering the possibility that you can increase bone length via the articular cartilage.

Regional shape change in adult facial bone curvature with age.

"hree-dimensional semilandmarks representing the curvature of the orbits, zygomatic arches, nasal aperture, and maxillary alveolar process were collected from a cross-sectional cranial sample of mixed sex and ancestry (male and female; African- and European-American), partitioned into three age groups (young adult = 18-39; middle-aged = 40-59 years; and elderly = 60+ years). Each facial region's semilandmarks were aligned into a common coordinate system via generalized Procrustes superimposition. Regional variation in shape was then explored via a battery of multivariate statistical techniques. Age-related shape differences were detected in the orbits, zygomatic arches, and maxillary alveolar process."

"adult craniofacial curvature shape is not static throughout human life. Instead, age-related spatial modifications occur in various regions of the craniofacial skeleton."

"Increases in craniofacial dimensions such as facial height, mandibular length, bizygomatic and bigonial breadth, and head circumference, length, and breadth have been detected with advancing age"

Natural craniofacial changes in the third decade of life: a longitudinal study.

"Natural head position lateral cephalometric films and dental casts of 30 people (14 women and 16 men) were evaluated. The mean age at the beginning of the observation period was 22.35 years for the women and 22.19 years for the men, and the observation period was approximately 10 years. Cephalometric films were superimposed by the structural method, and the measurements of the dental casts were made with a digital caliper. All tracings were digitized, and changes in the 65 cephalometric and 10 dental cast measurements were evaluated statistically. In this early adult period, small changes were found in the craniofacial and craniocervical parameters; the changes were more significant in the women. The most significant changes were found in the vertical dimension. The total anterior face height increased in both genders, while the lower anterior face height increased significantly in the female group. Soft tissue measurements reflected the vertical skeletal changes. The retrusion of the upper lip was significant in the women, and the upper lip thickness decreased in both genders. In the dentoalveolar region, the main movement was eruption of the teeth. The overbite amount increased significantly only in the female group. All dental arch measurements decreased in both sexes. The decrease in the mandibular arch length discrepancy was significant in the men."