Im tall and have chicken legs but very wide and strong back. Couldnt get my legs to grow no matter what until…I prioritised legs. Hit them Mondays and Thursdays. Squats, dropped the weight right down and would rep at a few sets of 100kg for 20 - 30 reps then 120 for 20 then 140 for sets to failure, but as many as i could do properly ass to the ground. Always squatted with very narrow stance. Did that for about 3 yrs. Never squatted more than 140 but built up to multiple sets of up to 50 reps Mever got injured squatting. Quads got up to almost 30 inches. All im saying is, a good reasonable weight for big reps built a ton of muscle. But even at that strength and size i doubt i could have even done 180kg for 1 and ill never know. Stopped training years ago. But I can still remember the swollen ego when i used to walk my 140 out of the rack and stand a good 15 feet from the rack and blast out 40 - 50 reps quietly. All heads used to turn on my leg days coz nobody else trained like that in my gym. My advise to anyone, with or without injury is train moderately heavy on back squats for max reps and best possible form literally until you chuck. It took my quads 3yrs to go from around 20 inches to almost 30.