Clinical Reasoning in the Absence of a Protocol: A Case Series of Physical Therapy Following Orthobiologic Interventions for Chronic Musculoskeletal Conditions.

Physical therapy following orthobiologic interventions occurs in a guidance vacuum, with limited standardized rehabilitation protocols to direct clinical decision-making; in this context, clinical reasoning becomes the operative mechanism through which therapists navigate the uncertainty inherent in postprocedural care. This retrospective case series documents and describes the clinical reasoning processes employed by a physical therapist managing three patients with chronic musculoskeletal conditions following orthobiologic interventions, without evaluating the efficacy of the orthobiologic or rehabilitative interventions. The three cases include 1) a 54-year-old woman with chronic shoulder pain involving a superior labral anterior-posterior tear, rotator cuff tendinosis, and adhesive capsulitis treated with three platelet-rich plasma injections and intermittent physical therapy over eight months; 2) a 38-year-old woman with a 20-year history of knee pain treated with bone marrow aspirate concentrate following arthroscopy and twice-weekly physical therapy for 12 weeks; and 3) a 47-year-old woman with sesamoid avascular necrosis of sesamoid bones of the great toe treated with a sequential series of autologous orthobiologic agents and four physical therapy visits over six months. Cases 1 and 3 demonstrated clinically meaningful improvements exceeding established minimal clinically important difference thresholds on standardized outcome measures and achieved return to prior functional levels, whereas Case 2 demonstrated meaningful functional gains during physical therapy but proceeded to total knee arthroplasty within three months of discharge, illustrating the boundaries of conservative management in advanced joint pathology. Common reasoning patterns across cases included reliance on tissue-response-based progression rather than time-based protocols, individualized loading strategies calibrated to patient-specific factors, and integration of orthobiologic context without allowing theoretical healing timelines to override clinical assessment. These cases illustrate the need for systematic documentation of clinical reasoning to build the practice-based evidence from which future protocols can be derived.