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Disclaimer : No content on this site, should ever be used as a substitute for direct medical advice from your doctor or other qualified clinician. Before believing that you suffer from hard flaccid syndrome, consult your doctor, do all the necessary tests to rule out any pathology. It is advisable to first proceed by elimination with the guidance of a health professional, who knows better than anyone else the tests that have to be done in regards to your symptoms. Hard Flaccid

HFI – Editorial staff.

Name of the syndrome

Hard flaccid

Variants

Firm flaccid

Acronyms

HF/HFS
LF/LHF (Long/large hard flaccid)

Definition

Hard flaccid syndrome is a chronic state of physical tension characterized by a stiff/hard penis while flaccid. The onset of symptoms occurs after  masturbation, jelq exercises, a sexual intercourse, a penile “injury”, a surgery such as a circumcision or vasectomy, from medication such as SSRI and 5-alpha reductase inhibitors.  This syndrome can also occur after a long period of intense stress including excessive genital focus and worries (STDs anxiety and all types of sexual anxieties.

Symptoms

– HF: The penis is hard, retracted and smaller than usual .
LHF: The penis is semi hard long/large, almost in semi erection.
– Changes (size /Coloration / shape / Shaft indent)
– Needles, tingling sensations
– Burning pain in the penis’s head and/or shaft
– Coldness in the penis’s head and/or shaft
– Numbness / Sensitive penis
– Redness, Dryness (Glans, foreskin)
– No morning erections
– Soft glans
– Chronic testicular pain / Epididymitis
– Dropping warm testicles (LHF)/ Tight and cold scrotum (HF)
– Varicocele

Some symptoms look like chronic pelvic pain syndrome (CPPS)*
. Pain when sitting for a long time (penis, tights, buttocks)
. Golf ball (The sensation of a ball in the anus)
. Loss of libido and erectile dysfunction (ED) (some cases)
. Weak urinary stream
. Frequent urination (some cases)
. Burning pain when urinate
. Chronic constipation/diarrhea.

* Many CPPS sufferers don’t have HF, most of them have never heard of this syndrome. The idea that hard flaccid could be a sub CPPS syndrome emerged about 14 years ago on the web because both syndromes share some similarities.

Physical Description

HF/LF,LHF: The penis is very often hard to the touch while flaccid and retracted without a cause to explain it. It is normal that in certain circumstances, all men experience from time to time a retracted and hard penis when it is cold, at the pool, during sustained effort or during a panic attack. However, it subsides so quickly that most men won’t even notice it.

What characterizes hard flaccid syndrome is the chronicity and duration of the symptoms. In short, it is a chronic condition.

A simple effort, a simple movement of the legs, a pelvic contraction or an abdominal contraction is enough to trigger the chain reaction that lead the penis to become hard or retracted and to remain in that state. Temperature can aggravate the intensity of the symptoms,  however temperature is not the cause of these symptoms . The mental state is also a powerful trigger. Emotions, stress and anxiety can aggravate the symptoms leading some sufferers to avoid stressful situations which makes daily life difficult to bear because a large number of stressors, whether physical or psychological, cannot be avoided as they are part of everyone’s daily life (job, social interactions, family and friends).

The stand up position and physical efforts involving legs and core muscles often aggravate the situation.
Sitting with the back slightly backward or lying down can sometimes relieve the symptoms but this is not always the case.

It is not uncommon for men to suffer from these symptoms for hours or even days on end, without any particular exogenous triggers to explain it. Once the syndrome has started, It keeps coming back from the inside on a daily basis(endogenous loop process).

 

Needles and tingling sensations: It is common that this state of tension leads to other sensory symptoms such as needles, tingling sensations. It happens most of the time while sitting, or while walking when the penis rubs against the underwear. 

 

Burning pain and coldness : Because the penis is constantly under tension (LHF) or retracted (HF), a number of men complain of a cold sensation, which particularly affects the glans and foreskin but can sometimes include the entire penis. The opposite occurs too, when the penis is not retracted but still hard. Men describe it as a burning sensation that concerns the glans, the foreskin but also the penis shaft, including a burning sensation in the veins.

 

Numbness: Some men reports that after a while, the penis becomes partially or totally insensitive to touch (numbness). In some cases, the numbness can unfortunately persist for months and even years (one case have had numbness for 15 years). This symptom is relatively common, however the severity varies from case to case. .

 

Redness: Inflammations may appear, such as redness on the glans and foreskin, which may suggest a bacterial(balanitis/balanoposthitis) or viral infection. However, all the tests aimed at proving that there is an infection fail without exception. These inflammations seem to be neurogenic.

 

ED – No morning erections: Although many cases do not present erection problems, a number of men complain of difficulty in obtaining or maintaining an erection. In almost all cases, erection requires manual stimulation to reduce the tension that the penis experiences daily in the flaccid state.

Erections can sometimes be painful, the tissues of the penis being under permanent tension, it is sometimes difficult to obtain full erections (some talk about “tight erections”). It is not uncommon for some men to see the size of their penis decrease both in erection and flaccid state. A loss of Girth is relatively common for people who have had this syndrome left untreated for several years.

In many cases, morning erections are absent or their qualities are diminished. Some men even wake up with a hard, retracted and sometimes painful penis. The pain tends to subside after urination.

 

The origin of the term

 

The name of the syndrome comes from PE(Penile enlargement exercises) communities and it emerged around 2007 on the web under the name of firm flaccid syndrome. However, even if the name comes from these communities, the syndrom itself does not excusively starts because of such kind of behaviors. It is quite possible to think that “correlation does not imply causation”, applies to this syndrome. Indeed, a number of men developed the same syndrome after a rought masturbation, a circumcision, a vasectomy, after taking certain medications, or after a burn out that lasted several consecutive months before the first symptoms appeared. 

The great known risk with PE exercises, is to develop scar tissues in the penis itself, however,  we have never read about someone complaining about HF that came back with positive tests for scar tissues in the penis. Regarding the different contexts in which the syndrome appears, it is unlikely that the syndrome is due to a direct penile injury. 

In Google Trend, some results appear in July 2007 for the words “hard flaccid”, between two quotes and for all countries combined. . Interest by region are : United States, United Kingdom, Canada, India. Google Trend does not represent the actual search volume numbers but rather an index ranging from 0-100. It displays an index ranging at 50 in July 2011 and 100 in November 2012 for those regions. The index ranging continues to fluctuate without interruption up to 2021

 Theories and potential causes of the syndrome

 

As up today this syndrome does not really exist for the medical profession, no one can 100% say with certainty what is the root cause(s) for HF, neither if it’s a physical issue or a chronic stress (CNS) induced tension. However it is somehow certain that the smooth muscles of the penis are mainly involved in the main symptom of the syndrome. The smooth muscles around the prostate, bladder and urethra could also be involved (see alpha blocker).

Except for 4 official publications [2,3,4,5], almost all of the “HF Literature” is based on personal experiences. In 2021 HF is still a big melting pot of ideas, it means that each one has its  own opinion.

Some have taken the hardline approach that HF is purely a physical condition and try to brute force the symptoms with static stretching and resistance stretching of the primer movers all around the pelvic floor (Quads, hamstrings, adductors, glutes, hip flexors, core muscles).

Others think that it’s a nerve compression of the pudendal nerve and canal alcock area.

Some think that this syndrome is a mind body tension disorder(GAD, chronic fight flight, complex PTSD) and that they’re suffering of a hyper reactive nervous system stuck in a kind of loop that needs to down regulate to release the muscle tension in the pelvic floor in order to release the tension into the penis itself. 

Some guess that: PE, stress/GAD/traumatic events, over masturbating, all share the same common physical behaviors such as to chronically over clenching the pelvic floor which would have led them step by step to develop the HF syndrome.

Obitoo the author of HF Unraveled(ebook format) released in 2013-14 [8], claimed for himself that it started after a massive nervous break down.


The muscular theory

As said above, there is a lack of medical support for decades, so it was necessary for people to find common points with existing syndromes. The idea emerged more than a decade ago that hard flaccid could be a sub CPPS(Chronic prostatic/pelvic Pain) syndrome. To make it simple as the penis takes root in the pelvic floor, HF would be due to a chronically tight pelvic floor, tight bulbocavernosus and ischiocavernosus muscles. This tension would lead to a chain reaction that would restrict the income and outcome blood flow into the penis as well as all the other symptoms HF sufferers have to deal with.

For years people have been going to physiotherapists and doing static stretching. Seeing that it doesn’t really work or that the results are unstable, a company called DCT for pelvic pain emerged about 4 years ago.

The basic theory is the same for CPPS and HF. The root cause would be muscle tension. However, this tension would not come from the pelvic floor itself, which would be just a bystander. It would come from the muscles around/surrounding the pelvic floor, hip flexors, hamstrings, quads, adductors, core muscles, low back,..).

The DCT theory says that static stretching do not work because they do not involve any muscle work. This technique consists of maintaining a contraction during the stretching sessions and limiting the stretching into the limit of the range of contraction. To make it short, the patient has to warm up with concentric then he does isometric contraction to be sure that the muscle he is working on is still engaged and only then starting the stretching phase while maintaining the contraction (eccentric contraction).

Although physical routines based on stretching and resistance stretching have shown some results, it is more of less clear that none of the routines designed to help with CPPS have been able to completely resolve the hard flaccid syndrome on a large numbers of practitioners. Only a few leaders/members have made that claim in years. 

It is worth noting that most of people with “strict” CPPS have never heard of hard flaccid syndrome before joining forums that mix both CPPS/HF sufferers and they do not complain about having a hard flaccid penis. What they do complain about are mainly urinary problems, burning sensations when urinating, rectal pain and pain when sitting for a long period of time. In most incapacitating cases, the sitting position is simply unbearable, which is not really the case for most people with hard flaccid syndrome. Long sitting can be uncomfortable and for some of them, numbing the penis and providing a burning sensation in thighs, gluts and the penis, but pain wise, the sitting position is most of the time bearable for HF sufferers. It’s above all the stiffness in the penis, numbness, coldness and penile pain that are the main complain with hard flaccid.  Not to mention that the main symptom of HF is “almost” and we would say, never mentioned in CPPS literature.

Hard flaccid is not officially a sub CPPS syndrome, and if both CPPS and HF seems at the first sight to be brothers, they are not identical twins.  Hard flaccid syndrome is just a web term, but because it shares these similarities with CPPS syndrome the treatments available since years for it are de facto the same as those for CPPS regardless the root cause.

In regard of the muscular theory (which has been tested and implemented for several years now), the question “is hard flaccid syndrome really a variant of CPPS?” is legitimate and deserves to be asked today.

The nerve compression theory

The other syndrome which hard flaccid syndrome is often associated with, is the pudendal neuralgia (PN). Indeed, there are a certain number of common points between these two syndromes. The pudendal neuralgia symptoms are : Numbness of the penis and scrotum, altered sensation of ejaculation, with disturbance of micturition, pain and discomfort while sitting. By the way, Pudendal Neuralgia is present on the French site Orpha.net, that’s a site dedicated to rare diseases.

However, the link between PN and HF is clearly not established yet. The context of appearance of the PN syndrome is not the same and the symptomatology differs between both PN and HF syndromes. That said the possibility that Hf would be due to a nerve compression cannot be excluded at all.

Pudendal nerve surgery is very controversial, with a number of PN patients complaining either that their situation has not improved or that the symptoms have worsened following the surgery. There are 4 decompression techniques, the transperineal technique, the transgluteal technique, the transvaginal or transischiorectal technique and the most recent of all, the laparoscopy technique. Laparoscopy is the least invasive form of surgery*.

*There is an unverified case of an reddit member suffering from hard flaccid syndrome who, according to his words, benefited from this surgery in Belgium and saw most of his symptoms disappear after the operation[12]. The surgeon would have proceeded to a decompression on the whole length of the Alcock canal instead of doing a simple decompression of the pudendal nerve. This case remains to be verified, the name of the surgeon was disclosed[12] and after verification this surgeon exercises well and truly in Belgium. He teaches this technique of decompression for about ten years.


The injury theory

A certain percentage of men who suffer from this syndrome have experienced symptoms while doing PE (Penile Enlargement) exercises, or after a prolonged masturbation/sexual intercourse (Including Edging which is a method of stretching out how long it takes to reach orgasm).

The problem with this theory is that no one over the last 14 years has been able to prove the existence of an injury. All ultrasounds performed by urologists are unable to show the existence of scar tissues in men complaining of hard flaccid syndrome. Besides, scar tissues are detectable, it is the way doctors find out if a patient has Peyronie’s disease. So, it is unlikely that hard flaccid syndrome could be a Peyronie. By the way, Peyronie’s disease is an inflamatory process, not an injury in the true sense of the word. 

Even if no one can totally discredit the injury theory at the moment, that’s important to notice that many men in history have suffered severe trauma to the groin and pelvic area with partial rupture of the corpora cavernosa. There is no mention in the medical literature of a syndrome similar to hard flaccid caused by trauma.

That said, the possibility of an injury in an area close to the lower part of the spine, pelvis, cannot totally be excluded as it is not possible at the moment to totally exclude that hard flaccid could be due to a nerve compression (Pudendal nerve/canal Alcock).

The STD’s theory

This theory has been partially obsolete for several years since no one has been able to prove the existence of an infection, be it bacterial or viral.


The prostatitis theory

This theory assumes that hard flaccid syndrome is actually a non-bacterial prostatitis. In fact, many urologists prescribe the same treatment for both urinary tract infections and prostate inflammation. When a man presents with hard flaccid, it is not uncommon for the health professional who is completely lost and overloaded with appointments to prescribe an antibiotic-based treatment as well as a selective alpha blocker type 1 (Tamsulosin).

However, here again, prostate disorders have been treated with antibiotics for years without much success. Moreover, some scientific articles mention that 95% of prostate inflammations don’t have a bacterial origin(Neurogenic inflammation).

What leads some men suffering from hard flaccid syndrome to make this link between prostatitis and HF is that the administration of an alpha blocker by blocking the type 1 adrenergic receptors all around the prostate, bladder and urethra, can reduce greatly the resistance of the smooth muscles present in the penis and can in some cases relieve the symptoms. However, this effect, although reported in the web literature, does not concern all men suffering from this syndrome. Moreover, when the medication is stopped, the symptoms return.

This theory still persists today because some claim to have “cured”[13] this syndrome(HF) by replicating a study published in 2013[1] aimed at treating prostatitis with an antifungal regimen coupled with an antifungal med(fluconazole). This study involved 1000 patients with prostatitis. The study report that 80% had an improvement in symptoms. The study concludes with this: An antifungal regimen should be considered for the majority of young adult men, presenting with chronic prostatitis/ chronic pelvic pain syndrome and incomplete response to antibiotics.

Another study was performed in 2018[2] on a patient with prostatitis for more than 20 years. In this study, fluconazole 400 mg/day was administered for a total of 8 weeks and then was discontinued. This treatment fixed the patient’s prostatitis. The patient was then followed-up for 6 months and no recurrence was observed.

Is hard flaccid a non bacterial prostatitis ? No one really knows as there is no medical support nor serious research done on this syndrome yet.

The anxiety/stress theory

A number of men with this syndrome have never exercised to increase their penis size, nor have they over masturbated. Some of them explain that the syndrome appeared after a long period of intense stress and that the symptoms worsen when there is stress. Some believe that this syndrome is due to a form of GAD (general anxiety disorder) or a PTSD/complex PTSD.  Following that theory, the body would simply be stuck in a neural loop, repeating the symptoms over and over again due to the initial emotional trauma.

However, it is important to note that the symptoms do not need stress to get worse. Contracting the core muscles, standing up, walking, making an effort is enough to aggravate the penile stifness. That said, the muscular tension theory cannot answer these simple questions: What is the root cause of the tension in these muscles ? What is the link between smooth muscles in the penis and striated muscles surrounding the pelvic floor ? Many talk about physical imbalances such as ATP, scoliosis, kyphosis, flat feet, but the medical profession never mentions hard flaccid as a symptom in these well known physical imbalances. None of the ppl with these physical imbalances know the syndrome. If hard flaccid is due to weak muscles why most men with it are in their early 20 ? Why do older men not complain of a hard flaccid penis ? All these questions lead some of them to think that hard flaccid could be a neurological/emotional trauma keeping the body under tension.


Other theories

Some people think that hard flaccid is due to a tear in the buck fascia, a hypermobile sacrum, a tear in coles fascia or even due to blood circulation problems, such as a form of venous leak.

It is unlikely that a venous leakage could explain the erectile dysfunction that some HF sufferers experience. Many men with HF have no ongoing erectile problems or no erectile problems at all but they have the other symtpoms. On the other hand, if a penis suffers from high pressure (if this analogy is allowed), it is not difficult to understand that the higher the tension in the smooth muscles of the penis, the greater the difficulty of getting or maintaining an erection. Furthermore a venous leak can be discovered during a medical examination (Ultrasound/caverjet).

 

The actual situation

 

The medical profession

The current situation is the same for more than 20 years now, except a few urologists who have tried to understand hard flaccid, most to the time the patient is told that it is all in his head. In some ways, it’s hard to blame them as hard flaccid is probably not a direct urological problem. However, when one consults for shoulder pain, the doctor tries to find out why it hurts, but when it concerns the penis, very quickly the patient is sent back home because it is very often automatically seen as a pure psychological problem.

Once the doctor diagnoses that this is psychological, the patient begins a descent into a downward spiral. He continues to suffer both psychologically and physically wise while nobody believes him. If family/friends are aware of the diagnosis, the patient is told by his surroundings to stop complaining.

That said, some urologists do the job, they perform an ultrasound, MRI, they check for STDs but find nothing. This is the reason why it’s nearly certain that this syndrome is not a direct urological condition and that the penis is a bystander, not the cause.

There is a need for scientific research and hard flaccid is far from being the only syndrome to be medically orphaned. To be honest, lhe lack of time, money and curiosity in the medical world is glaring.

For example, prostate inflammation is >90% of the time non-bacterial[14], yet urologists continue to give antibiotics without much conviction. 

In case of hard flaccid, the urologist think that it will pass. Unfortunately, this is not the case.  And this is almost never the case for hard flaccid, CPPS, or pudendal neuralgia. Some cases deal with these symptoms for decades in silence because to talk about it would be a double punishment, nobody take it seriously once the doctor says that it’s in the head.

The person who writes these lines has HF syndrome since 1999 and he’s not an isolated case. Today, groups exist to take care of the syndrome but It took years for the internet to become what it is today. 

Medical support is necessary because after a certain number of years of suffering, some people end up asking themselves what’s the point of continuing a day to day living without recognition, without medical explanation, without support. 

This is the main reason why this website has been created. The main purpose of this site is to have this syndrome recognized by the medical profession, because it is the first step to any future medical support. 

The situation on the web

On the web, the situation is a bit complicated too.  Left on his own, the patient can speculate endlessly only, then google is the only solution to get information. Unfortunately the search engine sends to many different conditions : Peyronie, venous leak, Mondor’s syndrome, prostatitis, pudendal neuralgia, STDs related infections and so on.   

Fortunately there are help groups for 3 years now that take care of the syndrome. The community is today split in 2 main groups. The first one is a private one on Facebook, owned by a private company selling stretching routines (DCT for pelvic pain with +600 members in 2021)[11]. The second one is an open group on Discord/Reddit[15] providing a free routine based on Youtube exercises videos (+1800 members 2021).

The current problem with these groups is that they mix different conditions all together. Some have erectile dysfunction but do not have HF, others have CPPS without having HF either. Everyone is in the same boat, because the explanation is the same for everyone and the treatment is a one fit for all physical routine without any real scientific causal link between the muscles and the symptoms.   

Lets face it, to be able to treat a medical condition, you have to be able to define the cause. This procedure requires neutral and skilled people (scientifics) who are able to distinguish between a placebo effect and a real therapeutic effect. This process is impossible when the only people who look into the matter are either patients or private companies.

Moreover, the term “Cure” is often used on the internet, however this word does not have much meaning when it comes to this syndrome. Medicine itself almost never uses this term, it speaks of remission for all chronic conditions. And hard flaccid is certainly one ot them. 

It means that the patient/client needs a follow up on a medium to long term basis in order to verify the stability of the situation. This is not the case on the internet at all. 

The situation is pretty much the same in these two groups, everyone is following a routine waiting to see who will be the next one to make a testimonial. In this context, nobody looks at the facts or the causes of the syndrome. Everyone wants it to work no matter the root cause and that’s understable, people want their life back as soon as possible.    

The company (DCT for pelvic pain [11]) that sells its routine sees its business relying on its results alone, which makes it difficult to access data. However, once one is a client, it is easy to see that the success rate is about 16-20 per more than 600 clients and it concerns males CPPS strict cases. This result falls down to 4 for hard flaccid cases in this same group. This rate has fallen even lower since the owners split up due to differences of opinion (The DCT 3.5 VS DCT 2.0 conflict). 

It is not uncommon that a person who declares to get 70% better, sees his symptoms to return with vengeance overnight during a flare up. This sudden return to ground zero after many months of training is very discouraging and suggests that the muscle theory alone is not sufficient to explain the cause and to treat the syndrome effectively.

Since the separation of the founders of the DCT, another theory has emerged.

According to David McCoid[10], co-founder and ex former member of DCT for pelvic pain, the low success rate of DCT is due to the fact that it is impossible to change the properties of the tissues surrounding the pelvic floor by simply doing resistance stretching. According to David, added loads are needed to change the tissues properties. Moreover the syndrome would not be due to real stiffness in the tissues surrounding the pelvic floor or in the pelvic floor itself. Stiffness is just a sensation and resistance stretching effect is neural. To make it short, feeling stiff, does not mean that the tissues are really stiff.

Without a scienfitic root cause and medical support,  the open group also suffers from this situation, as they cannot do anything but focus on what they think they know in hope to move forward. Whether it is the DCT or the Discord group, the situation is basically exactly the same. 

Hard flaccid is a chronic condition, an evolutionary process with ups and downs. It is easy to understand that as time goes by, the mind becomes unstable through suffering.  In this context and without medical support the door is wide open to temporary placebo effects and guilt when the proposed solutions do not work.  

It is not uncommon to tell people to have the warrior mindset when the routine does not work, or the results are unstable. Keep on is the rule. Disagree with that rule equal rejection and loneliness.  I know this because I am one of those people who have said “keep on”, “be strong”, YOLO,  hundreds of times. I understand the situation because I am one of these 70% recovered but not cured at all.

I have been a client of DCT for pelvic pain since 2018 and to create this site, which took about 10 months to be done(data included), a hundred people were contacted via whatsapp and messenger. As few people only from the DCT came to fill the 7 surveys on this site, I joined the Discord CPPS HF Rehab group, where i became a moderator for several months. I am still today a support member on that group. 

Text by Carlos.G & Roland.W – last update: Oct, 29 2021

Sources & links

 

1. Wikipedia – Hard flaccid syndrome.
Link: https://en.wikipedia.org/wiki/Hard_flaccid_syndrome

2. Hard flaccid syndrome: state of current knowledge – Maher Abdessater, Anthony Kanbar, William Akakpo, Sebastien Beley
Published online 2020 Jun 4 – PMID: 32518654 – DOI: 10.1186/s12610-020-00105-5
Link: https://pubmed.ncbi.nlm.nih.gov/32518654/

3. Hard flaccid: Is It a new syndrome? The Journal of Sexual Medicine – M. Gül, E.C. Serefoglu
Published online 2019 May 1 – DOI: 10.1016/j.jsxm.2019.03.194
Link: https://www.jsm.jsexmed.org/article/S1743-6095(19)30651-4/fulltext

4. Hard flaccid syndrome: initial report of four cases – Murat Gul, Maxwell Towe, Faysal A Yafi, Ege Can Serefoglu
Published online 2019 Mar 19 – PMID: 30890780 – DOI: 10.1038/s41443-019-0133-z
Link: https://www.nature.com/articles/s41443-019-0133-z

5. Urology News from UK: Hard flaccid syndrome – Kaylie Hughes, Arie Parnham and Marc Lucky
Published online 2018 Nov 1
Link: https://www.urologynews.uk.com/features/synopsis/post/hard-flaccid-syndrome

6. Chronic prostatitis/chronic pelvic pain syndrome: the role of an antifungal regimenahmed Fouad Kotb, asmaa Mohamed Ismail, Mohamed Sharafeldeen, Elsayed Yahia Elsayed University of Alexandria, Faculty of Medicine, Department of Urology, Alexandria, Egypt
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3936149/

7. Chronic prostatitis developing due to candida infection: A case diagnosed 20years later and review of up-to-date literatureAykut Demircia,∗, Nurten Bozlakb, Selçuk TurkelcaAksaray University Training and Research Hospıtal, Urology Department, TurkeybAksaray University Training and Research Hospıtal, Pathology Department, TurkeycAksaray University Training and Research Hospıtal, Microbiology Department, Turkey
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6077167/

8. Obitoo – HF Unraveled – © HardFlaccid.org 2014
The website is no longer available, the ebook can be found on CPPS HF Connect group on discord.
Here is the link: https://discord.gg/ragzeJWKA6

9. A headhache in the pelvis – by David Wise PhD (Author), Rodney U. Anderson MD (Author)
https://pelvicpainhelp.com/

10. Freedom From Pelvic Pain – David McCoid
Link: https://freedomfrompelvicpain.com/

11. DCT (Dynamic Contraction Techniques) – Nic Bartollota, Rocco Castellano.
Link: https://dynamiccontractiontechnique.com/

12. A reddit member claim that the laparoscopy surgery solved HF.
Link: https://www.reddit.com/r/Hard_Flaccid/comments/p8xto9/the_most_important_post_on_hard_flaccid_that_will/
The surgeon is Renaud Bollens, Urologist in Ath, Belgium

13. Emil Arwidsson
Link: https://www.hardflaccid.co

14. Sciencedirect – Prostatitis.
https://www.sciencedirect.com/science/article/pii/S1879522617300374

15. Discord CPPS HF Rehab support group.
https://www.reddit.com/r/Hard_Flaccid/comments/jkcjkn/join_the_hf_cpps_discord_server/