So far, concerns from the Xiao procedure are:
First, not having a control group. Selective sacral rhizotomy is used in the management of neurogenic bladders. Even the artificial reflect arc doesn't take effect, the surgery may improve the function of neurogenic bladder as it cuts anterior roots of nerves. The efficacy at the early stage is not caused by reflect arc. Without control group, we cannot tell if the results is down to selective sacral severance or because of reflect arc.
This is the most deadly mistake in reflect arc study, which is also overlooked by most domestic and foreign urology experts! People observe improvement in urination then conclude that the reflect arc takes effect. How could an urologist simply accept the conclusion? Especially for those American big-name experts. The evaluation for efficacy should be based on urodynamic testing data, particularly the detrusor pressure exerted by a bladder.

Second, urodynamic material. One of Xiao's paper titled "Reinnervation for neurogenic bladder: historic review and introduction of a somatic-autonomic reflex pathway procedure for patients with spinal cord injury or spina bifida" was published on Eur Urol, 2006 Jan;49(1):22-8; discussion 28-9. The figure reveals truth inside the reflection arc. Figure 3B and Figure 4B were got from postoperative urodynamic testing. The results undoubtedly show that patients apply pressure on abdomen to urinate. But Xiao explained that it is reflect arc to cause the urination. The flaw was ignored by editors. The evidence is that the abdominal pressure (Pabd) is as same as intravesical pressure (Pves). And the detrusor pressure (Pdel) is very low (a flat line), nearly to zero. Voiding was done by applying abdomen pressure.

Third, other reports in articles by Xiao, et al shows ineffective results.
One article titled "Comparison of clinical outcomes of the Xiao somatic-central nervous system-autonomic reflex operations between the domestic and foreign cases" reports: 2 cases in U.S.A, the max flow rate was 8cc/s and post-void residual was 200cc/s. Abstract: "At last follow-up (15 months) L5 stimulation caused a detrusor contraction of 59cm H20, a Q max of 8 cc/sec and no DESD. Voided volume was 150cc and post-void residual was 200 cc's. (2005 AUA). Any urologist knows that the normal value of the max flow rate for male ≥ 20 ml/s, for female ≥ 25ml/s. If the max flow rate ≤ 10ml/s, it should be considered as abnormal results. It may due to lower ureteral obstruction or neurogenic bladder. (Urology, editor in chief: Jieping Wu, P804). These 2 cases have the max flow rate of 8cc/s and residual of 200ml. How could those results show efficacy?
One post appeared on Starlakeporch forum on Nov 15th with title of "Nobody can doubt this news", with photos. Any Urologist can find that it is a typical voiding by abdomen pressure as soon as seeing the photo. "Push, Push!" Shanshan's mom told him. Those words is to ask him increase abdomen pressure. Bladder function can not be controlled by our conscious mind. Increasing abdomen pressure can help bladder voiding. Electronic stimulation is required for voiding in the past. Now it isn't used at all. Why? reflect arc doesn't work without electronic stimulus. The case which Xiao is most proud of failed. If someone doesn't believe it, please print the photo out and ask an urologist to judge.
Untrained people observe voiding then think that the surgery is effective. In fact, from a professional view of Urology, we should identify if voiding is by abdomen pressure or detrusor contraction pressure. In the case of Shanshan, reflect arc is infective. Some bladder cancer patients receive treatments to remove bladder and replace it with a loop of intestine. The new bladder can not contract (it requires non-contracting. Contracting has negative factors). Patients are trained to void by applying abdomen pressure after operation. After a period of time, patients may attain normal voiding. Most of readers can now understand why we said that urine was evacuated by abdominal pressure and reflect arc was ineffective in Shashan case.
In "Rough translation of one year's summary", they don't provide any key urodynamic data, such as abdomen pressure (Pabd), intravesical pressure (Pves), detrusor pressure. The key to evaluate efficacy of reflect arc is urodynamic testing, particularly data of detrusor pressure (Pdel) and abdomen pressure (Pabd).
The stimulus in Xiao procedure may not be strong enough to initiate the reflect. The first year medical students know that stimulus must be greater than a threshold to initiate the reflect. As normal people know, the lower leg kicks forward when the patellar tendon is tapped. The strength of tapping should be at least greater than a threshold value. Could knee jerk be initiated by scratching the knee?
Conclusion: reflect arc is ineffective itself. But selective sacral severance within the operation contributes improvement for part of patients. But the Xiao procedure sever less never roots than rhizotomy. It can not be more effective than rhizotomy. One member in DXY, skyy said: one aim of such kind of function reconstruction for neurogenic bladder is to realize "hold urine at low pressure while evacuate urine at low pressure". It points out the essential of the artificial reflect arc. The clinical cases that bladder cancer patients being treated with cystectomy attain normal voiding by applying abdomen pressure is the best example using "hold urine at low pressure while evacuate urine at low pressure".