Capsule preservation improves short-term outcome of hydraulic distension in painful stiff shoulder.

The effect of intraarticular hydraulic distension (IHD) for a painful stiff shoulder (or adhesive capsulitis) has been affirmed, but whether rupturing the joint capsule during this process is beneficial remains controversial. By monitoring real-time pressure–volume (PV) profiles during IHD, we could infuse the largest possible volume without rupturing the capsule. Using the novel technique, we compared the short-term effects of IHD when the capsule was preserved versus when it was ruptured. Fifty-four patients with a painful stiff shoulder underwent IHDs intended to preserve or rupture the capsule and then classified into capsule-ruptured (n = 26) and capsule-preserved (n = 20) groups, based on the obtained PV profiles. Their profiles were triphasic or biphasic; eight with flat profiles were excluded from the comparison. Clinical outcomes were evaluated at 3-day and 1-month follow-ups, in terms of pain and range of motion (ROM). Although both groups showed significant increase in ROM and decrease in pain after IHD, the improvements were greater in the capsule-preserved group than in the ruptured group at both follow-up times, and in triphasic and biphasic cases. In conclusion, the therapeutic effects of IHD in short-term follow-ups were enhanced by preserving the capsule. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 29:1688–1694, 2011