The quivering needle hits the 30kg mark, the maximum weight Yasser can put on his leg since an explosion in his native Yemen ripped through the limb.
In downtown Amman, in Jordan, hundreds of people like Yasser are under the care of MSF doctors treating war wounded victims of some of the region’s most brutal wars.
Hussein Odat encourages his patient to keep going as he winces in agony.
“It’s painful for him, that’s why the needle is shaking,” says Dr Odat in the hospital’s busy physiotherapy unit.
“He’s finding it difficult to maintain that weight.”
Around us, young children practice routines under the eagle eyes of physiotherapists who correct minute repetitions of movement as the children scrunch their faces in concentration.
For these patients, this is one small step in a seemingly endless road peppered with surgeries and rehabilitation as they struggle to rebuild lives shattered by violence rippling throughout the Middle East.
The poorest country in the Middle East, Yemen is home to a large percentage of war wounded patients accessing the services in the hospital.
The country, which has become an international battleground for old rivals Saudi Arabia and Iran, consists of a series of armies and militias vying for territory.
This has pushed nearly 17m people to the brink of starvation and, according to the UN, Yemen is the world’s largest humanitarian crisis.
Yasser, who underwent a painful bone graft to repair his injured leg, bears the human cost for of a brutal bombing campaign on Yemen.
After his initial bone graft was stalled, he now hopes he can move forward as doctors gradually stretch the bones in his leg through a network of external metal screws protruding from his once healthy body.
The young Yemeni waits stoically for his next procedure, as US president Donald Trump concludes his visit to Middle East where he celebrated a $110bn (€98bn) arms deal with Saudi Arabia — arms which will undoubtedly fall from Yemen’s skies.
The conflict in Yemen is grossly under-reported. Access to the region is risky and all the main arteries involve a collision course with the country’s kaleidoscope of armed groups.
Yemen’s main airport in the capital, Sanaa, closed in 2015 after being targeted by Saudi airstrikes. Saudi has also blockade the county’s ports in a bid to stop the shipment of arms from Iran.
Inside the country, al Qaeda in the Arabian Peninsula made huge gains under President Abdrabbuh Mansour Hadi, who came to power following a 2011 protest movement that outed President Abdullah Saleh.
The country is now in dire straits with Al Qaeda, Islamic State, Houthi rebels and those loyal to Mr Hadi all battling it out with weapons provided by the international community.
For those who were part of Yemen’s Arab Spring, the outlook became bitter almost immediately.
Wael (pictuted above), a 28-year-old football fan, has been coming to Jordan since 2012, and has gone through dozens of surgeries after suffering third degree burns when his protest group were attacked in 2011.
“His face is much better now,” Abu Sammour, a nurse in the hospital, whispers as Wael talks us through the improvements to his body.
“My father said I was broken, that I couldn’t be fixed. But I said no, and I am getting better,” he smiled before joking over the results of a recent football match.
“Because I spend so long in the hospital, I watch every football game and every championship you can think of,” he laughed.
Wael’s determination is admirable and he will need it. All patients return to Yemen after receiving treatment in the hospital. The doctors follow their progress and attempt to bring them back to Jordan when they need further surgeries, a process that can often be a logistical nightmare.
“I’m glad it’s not my job,” clinical director Bill Thompson said wearily inside a small room where an artist is getting ready to start painting the children’s area.
Mr Thompson explains that getting patients in and out of Yemen is a complex process, with Saudi controlling the ports in the south, and Houthis swaths of land in the north, along with the capital.
For Wael and Yasser, an uncertain future awaits. Most Yemenis depend on food aid and unless vital aid targets are met, millions people face starvation.
To add to the country’s misery, the Trump’s administration is considering reducing US funding for UN humanitarian programs by 50%.
That will undoubtedly have an impact on the 2m-plus children in the country who are acutely malnourished.
While the US debates aid and sells weapons, EU countries also continue to sell arms to Saudi Arabia unnoticed.
Add to that a confused US strategy — al Qaeda in the region claims it sometimes fights alongside US-backed militias — and a desperate humanitarian disaster becomes that bit more desperate.
The fighting has lead to massive displacement and with that comes the trapping of disease.
From May 14 to May 19, the number of identified cases of cholera rose from 11,000 to 23,500. In under one week, the disease spread throughout the country leaving the country’s already fragile healthcare system completely overwhelmed.
According to Yemen’s Ministry of Public Health and Population, the disease has now spread to 18 of the country’s 22 governorates.
In Jordan, Yasser continues to patiently practice his exercises and waits each day for the screws in his leg to stretch his bone 1mm.
“It’s painful because it stretches the soft tissue too,” Dr Odat explains as an elderly Syrian man winces next to us trying to complete a simple leg movement.
Patients try to remain hopeful as each surgery brings with it an uphill battle to reclaim basic human dignity.
“I am happy with my new procedure. Things are slowly getting better for me,” Yasser says quietly as the needle shakes beneath his foot.