Based on the present meta-analysis, physical therapy following RIRS and ESWL did improved the SFR at different time points, especially the stone location in lower calyx (OR: 3.51; 95% CI: 2.21–5.55; p < 0.0001) and renal pelvis/upper ureter (OR: 2.79; 95% CI: 1.62–4.81; p = 0.0002) benefit much more from the physical therapy than the stone in other locations (upper calyx and middle calyx). Furthermore, the physical therapy did not bring more complication (all P> 0.05).
Currently, with popular of minimal invasive or non-invasive techniques, the stone clearance has become the first consideration after lithotripsy, especially spontaneous passage was needed in ESWL and RIRS. A better way to facilitate the residual stone fragment passage and improve SFR was worldwide discussed. As was known, a serial of factors would influence the spontaneous passage of the stone fragments following RIRS and ESWL, for example, lower pole stones, multiple calyceal stones, large stone burden and stone density parameters were reported to affect the SFR significantly [39, 40]. Others factors such as ureter condition, washing of urine, and ureteral smooth muscle movement should also be taken into consideration [41].
After the ESWL and RIRS, what we can do to improve the SFR was that, facilitate the stone fragments into the ureter, pushing the fragments passage from the dilated ureter, thus self-help position therapy, diuresis, relaxation ureteral smooth muscle was tried [17, 25].
In 2000, Honey et.al [42] reported PDI (percussion diuresis and inversion) can effectively mobilize residual stones out of the lower pole calyces, and eventually assist passage of fragments. In the meta-analysis published in 2013 from Liu et.al, limited evidence from two small studies indicated that PDI was safe and effective to assist clearance of LCS after ESWL (RR: 0.62, 95% CI: 0.47-0.82). Owing to the limited number of studies enrolled and rapid development of techniques, a pooled analysis based on this were required to discuss the clinical prospect of physical therapies. Fortunately, the present meta-analysis enrolled more studies and again testified the effectiveness of PDI in improving SFR following ESWL and RIRS, especially the LCS and UPS, indicating that physical therapy for such special location stones would work.
With the increasing experience and regeneration of equipment, a new device called EPVL was invented in China, which can provide a well-controlled inversion and changing body position from a rotating couch, and also a circled mechanical percussion [32]. It was reported to improve the SFR following ESWL and RIRS. With multiple approaches for mechanical percussion, effective percussion could be performed. In 2016, Zhang et.al [43] performed a meta-analysis in Chinese enrolling Five randomized or Quasi-randomized controlled trials and demonstrated that EPVL was effective in promoting upper urinary tract residual stones expulsion (OR = 4.50, 95% CI:2.02-10.00, p=0.0002). According to subgroup analysis in present meta-analysis, the application of EPVL provided a higher SFR after ESWL and RRIS (OR: 3.47; 95% CI: 2.24–5.37; p < 0.0001), as well as PDI (OR: 3.24; 95% CI: 2.01–5.21; p < 0.0001). Given that there were no standard protocol for physical therapy, EPVL might provide a relative uniformed and repeatable protocol for clinical practice, thus more practical than other physical therapy.
Zhang et.al [44] investigated the potential ideal time to perform EPVL after RIRS, in which 3 days, 7 days, 14 days after RIRS were compared. They found that, the best time to perform EPVL was 3 days after RIRS, with a high SFR (final SFR: 91.11%) at any time points. However, the appropriate time point to performed the first session physical therapy was still not conclusive, since the present study did not get enough information from the enrolled studies.
Medical expulsive therapy (MET), including diuretics, Chinese patent medicine, α-receptor blockers (tamsulosin) had been used as auxiliary procedure to improve SFR. But the role of tamsulosin in dilation ureteral luminal was still controversial, as well as other medicines. In a three-arm study, Liu et.al [30] compared EPVL combined with tamsulosin, EPVL alone and tamsulosin alone, and found that, EPVL combined with tamsulosin could promote a higher SFR for distal ureteral stone fragments when compared the other two groups in the first week (91.1% vs. 50.5% vs.50%, P < 0.05). However, there was no significant difference in final SFR (94.5%, 93.5% and 93.6%, p > 0.05). Diuresis was supposed to help stone fragments expulsion through urine washing, studies enrolled in present meta-analysis recommended enough water drinking before physical therapy (1000-3000ml). However, the volume of drinking water, when to drink, and the role of furosemide was still inconclusive, since limited information was got from the enrolled studies. Thus, further investigations were required to testify the role of combined physical therapy and MET.
When it came to the complications of physical therapy, we did not found any significant difference in terms of hematuria, lumbago and urinary infection between physical therapy and observation group, but inversion during physical therapy might cause dizziness even though with no statistical significance (OR: 2.88; 95% CI: 0.89-9.39; p= 0.078). EPVL and PDI facilitated the stone fragments passage, but did not increase the risk of renal colic and strainstrass formation in the present meta-analysis.
To be noticed, there was several limitations about this meta-analysis. The primary limitation was the small number of eligible studies and sample sizes. In addition, the appropriate time point to performed the first session physical therapy, and the role of tamsulosin and diuresis in physical therapy was still inconclusive, which need further investigations. With growing need of physical therapy, a standard protocol for mechanical percussion and inversion was required to be built in the near future. well-designed and large sample RCTs was still demanded to assess details of physical therapy.